[dragonfly.git] / sys / dev / netif / ath / ath / if_ath.c

/*-
 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
 *    redistribution must be conditioned upon including a substantially
 *    similar Disclaimer requirement for further binary redistribution.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGES.
 *
 * $FreeBSD: head/sys/dev/ath/if_ath.c 203751 2010-02-10 11:12:39Z rpaulo $");
 */

/*
 * Driver for the Atheros Wireless LAN controller.
 *
 * This software is derived from work of Atsushi Onoe; his contribution
 * is greatly appreciated.
 */

#include "opt_inet.h"
#include "opt_ath.h"
#include "opt_wlan.h"

#include <sys/param.h>
#include <sys/systm.h> 
#include <sys/sysctl.h>
#include <sys/mbuf.h>   
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/errno.h>
#include <sys/callout.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/kthread.h>
#include <sys/taskqueue.h>
#include <sys/priv.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/if_arp.h>
#include <net/if_llc.h>
#include <net/ifq_var.h>

#include <netproto/802_11/ieee80211_var.h>
#include <netproto/802_11/ieee80211_regdomain.h>
#ifdef IEEE80211_SUPPORT_SUPERG
#include <netproto/802_11/ieee80211_superg.h>
#endif
#ifdef IEEE80211_SUPPORT_TDMA
#include <netproto/802_11/ieee80211_tdma.h>
#endif

#include <net/bpf.h>

#ifdef INET
#include <netinet/in.h> 
#include <netinet/if_ether.h>
#endif

#include <dev/netif/ath/ath/if_athvar.h>
#include <dev/netif/ath/hal/ath_hal/ah_devid.h>         /* XXX for softled */

#ifdef ATH_TX99_DIAG
#include <dev/netif/ath_tx99/ath_tx99.h>
#endif

/*
 * ATH_BCBUF determines the number of vap's that can transmit
 * beacons and also (currently) the number of vap's that can
 * have unique mac addresses/bssid.  When staggering beacons
 * 4 is probably a good max as otherwise the beacons become
 * very closely spaced and there is limited time for cab q traffic
 * to go out.  You can burst beacons instead but that is not good
 * for stations in power save and at some point you really want
 * another radio (and channel).
 *
 * The limit on the number of mac addresses is tied to our use of
 * the U/L bit and tracking addresses in a byte; it would be
 * worthwhile to allow more for applications like proxy sta.
 */
CTASSERT(ATH_BCBUF <= 8);

/* unaligned little endian access */
#define LE_READ_2(p)                                                    \
        ((u_int16_t)                                                    \
         ((((u_int8_t *)(p))[0]      ) | (((u_int8_t *)(p))[1] <<  8)))
#define LE_READ_4(p)                                                    \
        ((u_int32_t)                                                    \
         ((((u_int8_t *)(p))[0]      ) | (((u_int8_t *)(p))[1] <<  8) | \
          (((u_int8_t *)(p))[2] << 16) | (((u_int8_t *)(p))[3] << 24)))

static struct ieee80211vap *ath_vap_create(struct ieee80211com *,
                    const char name[IFNAMSIZ], int unit, int opmode,
                    int flags, const uint8_t bssid[IEEE80211_ADDR_LEN],
                    const uint8_t mac[IEEE80211_ADDR_LEN]);
static void     ath_vap_delete(struct ieee80211vap *);
static void     ath_init(void *);
static void     ath_stop_locked(struct ifnet *);
static void     ath_stop(struct ifnet *);
static void     ath_start(struct ifnet *);
static int      ath_reset(struct ifnet *);
static int      ath_reset_vap(struct ieee80211vap *, u_long);
static int      ath_media_change(struct ifnet *);
static void     ath_watchdog_callout(void *);
static int      ath_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
static void     ath_fatal_proc(void *, int);
static void     ath_bmiss_vap(struct ieee80211vap *);
static void     ath_bmiss_task(void *, int);
static int      ath_keyset(struct ath_softc *, const struct ieee80211_key *,
                        struct ieee80211_node *);
static int      ath_key_alloc(struct ieee80211vap *,
                        struct ieee80211_key *,
                        ieee80211_keyix *, ieee80211_keyix *);
static int      ath_key_delete(struct ieee80211vap *,
                        const struct ieee80211_key *);
static int      ath_key_set(struct ieee80211vap *, const struct ieee80211_key *,
                        const u_int8_t mac[IEEE80211_ADDR_LEN]);
static void     ath_key_update_begin(struct ieee80211vap *);
static void     ath_key_update_end(struct ieee80211vap *);
static void     ath_update_mcast(struct ifnet *);
static void     ath_update_promisc(struct ifnet *);
static void     ath_mode_init(struct ath_softc *);
static void     ath_setslottime(struct ath_softc *);
static void     ath_updateslot(struct ifnet *);
static int      ath_beaconq_setup(struct ath_hal *);
static int      ath_beacon_alloc(struct ath_softc *, struct ieee80211_node *);
static void     ath_beacon_update(struct ieee80211vap *, int item);
static void     ath_beacon_setup(struct ath_softc *, struct ath_buf *);
static void     ath_beacon_proc(void *, int);
static struct ath_buf *ath_beacon_generate(struct ath_softc *,
                        struct ieee80211vap *);
static void     ath_bstuck_task(void *, int);
static void     ath_beacon_return(struct ath_softc *, struct ath_buf *);
static void     ath_beacon_free(struct ath_softc *);
static void     ath_beacon_config(struct ath_softc *, struct ieee80211vap *);
static void     ath_descdma_cleanup(struct ath_softc *sc,
                        struct ath_descdma *, ath_bufhead *);
static int      ath_desc_alloc(struct ath_softc *);
static void     ath_desc_free(struct ath_softc *);
static struct ieee80211_node *ath_node_alloc(struct ieee80211vap *,
                        const uint8_t [IEEE80211_ADDR_LEN]);
static void     ath_node_free(struct ieee80211_node *);
static void     ath_node_getsignal(const struct ieee80211_node *,
                        int8_t *, int8_t *);
static int      ath_rxbuf_init(struct ath_softc *, struct ath_buf *);
static void     ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
                        int subtype, int rssi, int nf);
static void     ath_setdefantenna(struct ath_softc *, u_int);
static void     ath_rx_task(void *, int);
static void     ath_txq_init(struct ath_softc *sc, struct ath_txq *, int);
static struct ath_txq *ath_txq_setup(struct ath_softc*, int qtype, int subtype);
static int      ath_tx_setup(struct ath_softc *, int, int);
static int      ath_wme_update(struct ieee80211com *);
static void     ath_tx_cleanupq(struct ath_softc *, struct ath_txq *);
static void     ath_tx_cleanup(struct ath_softc *);
static void     ath_freetx(struct mbuf *);
static int      ath_tx_start(struct ath_softc *, struct ieee80211_node *,
                             struct ath_buf *, struct mbuf *);
static void     ath_tx_task_q0(void *, int);
static void     ath_tx_task_q0123(void *, int);
static void     ath_tx_task(void *, int);
static void     ath_tx_draintxq(struct ath_softc *, struct ath_txq *);
static int      ath_chan_set(struct ath_softc *, struct ieee80211_channel *);
static void     ath_draintxq(struct ath_softc *);
static void     ath_stoprecv(struct ath_softc *);
static int      ath_startrecv(struct ath_softc *);
static void     ath_chan_change(struct ath_softc *, struct ieee80211_channel *);
static void     ath_scan_start(struct ieee80211com *);
static void     ath_scan_end(struct ieee80211com *);
static void     ath_set_channel(struct ieee80211com *);
static void     ath_calibrate_callout(void *);
static int      ath_newstate(struct ieee80211vap *, enum ieee80211_state, int);
static void     ath_setup_stationkey(struct ieee80211_node *);
static void     ath_newassoc(struct ieee80211_node *, int);
static int      ath_setregdomain(struct ieee80211com *,
                    struct ieee80211_regdomain *, int,
                    struct ieee80211_channel []);
static void     ath_getradiocaps(struct ieee80211com *, int, int *,
                    struct ieee80211_channel []);
static int      ath_getchannels(struct ath_softc *);
static void     ath_led_event(struct ath_softc *, int);

static int      ath_rate_setup(struct ath_softc *, u_int mode);
static void     ath_setcurmode(struct ath_softc *, enum ieee80211_phymode);

static void     ath_sysctlattach(struct ath_softc *);
static int      ath_raw_xmit(struct ieee80211_node *,
                        struct mbuf *, const struct ieee80211_bpf_params *);
static void     ath_announce(struct ath_softc *);
static void     ath_sysctl_stats_attach(struct ath_softc *sc);

#ifdef IEEE80211_SUPPORT_TDMA
static void     ath_tdma_settimers(struct ath_softc *sc, u_int32_t nexttbtt,
                    u_int32_t bintval);
static void     ath_tdma_bintvalsetup(struct ath_softc *sc,
                    const struct ieee80211_tdma_state *tdma);
static void     ath_tdma_config(struct ath_softc *sc, struct ieee80211vap *vap);
static void     ath_tdma_update(struct ieee80211_node *ni,
                    const struct ieee80211_tdma_param *tdma, int);
static void     ath_tdma_beacon_send(struct ath_softc *sc,
                    struct ieee80211vap *vap);

static __inline void
ath_hal_setcca(struct ath_hal *ah, int ena)
{
        /*
         * NB: fill me in; this is not provided by default because disabling
         *     CCA in most locales violates regulatory.
         */
}

static __inline int
ath_hal_getcca(struct ath_hal *ah)
{
        u_int32_t diag;
        if (ath_hal_getcapability(ah, HAL_CAP_DIAG, 0, &diag) != HAL_OK)
                return 1;
        return ((diag & 0x500000) == 0);
}

#define TDMA_EP_MULTIPLIER      (1<<10) /* pow2 to optimize out * and / */
#define TDMA_LPF_LEN            6
#define TDMA_DUMMY_MARKER       0x127
#define TDMA_EP_MUL(x, mul)     ((x) * (mul))
#define TDMA_IN(x)              (TDMA_EP_MUL((x), TDMA_EP_MULTIPLIER))
#define TDMA_LPF(x, y, len) \
    ((x != TDMA_DUMMY_MARKER) ? (((x) * ((len)-1) + (y)) / (len)) : (y))
#define TDMA_SAMPLE(x, y) do {                                  \
        x = TDMA_LPF((x), TDMA_IN(y), TDMA_LPF_LEN);            \
} while (0)
#define TDMA_EP_RND(x,mul) \
        ((((x)%(mul)) >= ((mul)/2)) ? ((x) + ((mul) - 1)) / (mul) : (x)/(mul))
#define TDMA_AVG(x)             TDMA_EP_RND(x, TDMA_EP_MULTIPLIER)
#endif /* IEEE80211_SUPPORT_TDMA */

SYSCTL_DECL(_hw_ath);

/* XXX validate sysctl values */
static  int ath_longcalinterval = 30;           /* long cals every 30 secs */
SYSCTL_INT(_hw_ath, OID_AUTO, longcal, CTLFLAG_RW, &ath_longcalinterval,
            0, "long chip calibration interval (secs)");
static  int ath_shortcalinterval = 100;         /* short cals every 100 ms */
SYSCTL_INT(_hw_ath, OID_AUTO, shortcal, CTLFLAG_RW, &ath_shortcalinterval,
            0, "short chip calibration interval (msecs)");
static  int ath_resetcalinterval = 20*60;       /* reset cal state 20 mins */
SYSCTL_INT(_hw_ath, OID_AUTO, resetcal, CTLFLAG_RW, &ath_resetcalinterval,
            0, "reset chip calibration results (secs)");

static  int ath_rxbuf = ATH_RXBUF;              /* # rx buffers to allocate */
SYSCTL_INT(_hw_ath, OID_AUTO, rxbuf, CTLFLAG_RW, &ath_rxbuf,
            0, "rx buffers allocated");
TUNABLE_INT("hw.ath.rxbuf", &ath_rxbuf);
static  int ath_txbuf = ATH_TXBUF;              /* # tx buffers to allocate */
SYSCTL_INT(_hw_ath, OID_AUTO, txbuf, CTLFLAG_RW, &ath_txbuf,
            0, "tx buffers allocated");
TUNABLE_INT("hw.ath.txbuf", &ath_txbuf);

static  int ath_bstuck_threshold = 4;           /* max missed beacons */
SYSCTL_INT(_hw_ath, OID_AUTO, bstuck, CTLFLAG_RW, &ath_bstuck_threshold,
            0, "max missed beacon xmits before chip reset");

#ifdef ATH_DEBUG
enum {
        ATH_DEBUG_XMIT          = 0x00000001,   /* basic xmit operation */
        ATH_DEBUG_XMIT_DESC     = 0x00000002,   /* xmit descriptors */
        ATH_DEBUG_RECV          = 0x00000004,   /* basic recv operation */
        ATH_DEBUG_RECV_DESC     = 0x00000008,   /* recv descriptors */
        ATH_DEBUG_RATE          = 0x00000010,   /* rate control */
        ATH_DEBUG_RESET         = 0x00000020,   /* reset processing */
        ATH_DEBUG_MODE          = 0x00000040,   /* mode init/setup */
        ATH_DEBUG_BEACON        = 0x00000080,   /* beacon handling */
        ATH_DEBUG_WATCHDOG      = 0x00000100,   /* watchdog timeout */
        ATH_DEBUG_INTR          = 0x00001000,   /* ISR */
        ATH_DEBUG_TX_PROC       = 0x00002000,   /* tx ISR proc */
        ATH_DEBUG_RX_PROC       = 0x00004000,   /* rx ISR proc */
        ATH_DEBUG_BEACON_PROC   = 0x00008000,   /* beacon ISR proc */
        ATH_DEBUG_CALIBRATE     = 0x00010000,   /* periodic calibration */
        ATH_DEBUG_KEYCACHE      = 0x00020000,   /* key cache management */
        ATH_DEBUG_STATE         = 0x00040000,   /* 802.11 state transitions */
        ATH_DEBUG_NODE          = 0x00080000,   /* node management */
        ATH_DEBUG_LED           = 0x00100000,   /* led management */
        ATH_DEBUG_FF            = 0x00200000,   /* fast frames */
        ATH_DEBUG_DFS           = 0x00400000,   /* DFS processing */
        ATH_DEBUG_TDMA          = 0x00800000,   /* TDMA processing */
        ATH_DEBUG_TDMA_TIMER    = 0x01000000,   /* TDMA timer processing */
        ATH_DEBUG_REGDOMAIN     = 0x02000000,   /* regulatory processing */
        ATH_DEBUG_FATAL         = 0x80000000,   /* fatal errors */
        ATH_DEBUG_ANY           = 0xffffffff
};
static  int ath_debug = 0;
SYSCTL_INT(_hw_ath, OID_AUTO, debug, CTLFLAG_RW, &ath_debug,
            0, "control debugging printfs");
TUNABLE_INT("hw.ath.debug", &ath_debug);

#define IFF_DUMPPKTS(sc, m) \
        ((sc->sc_debug & (m)) || \
            (sc->sc_ifp->if_flags & (IFF_DEBUG|IFF_LINK2)) == (IFF_DEBUG|IFF_LINK2))
#define DPRINTF(sc, m, fmt, ...) do {                           \
        if (sc->sc_debug & (m))                                 \
                kprintf(fmt, __VA_ARGS__);                      \
} while (0)
#define KEYPRINTF(sc, ix, hk, mac) do {                         \
        if (sc->sc_debug & ATH_DEBUG_KEYCACHE)                  \
                ath_keyprint(sc, __func__, ix, hk, mac);        \
} while (0)
static  void ath_printrxbuf(struct ath_softc *, const struct ath_buf *bf,
        u_int ix, int);
static  void ath_printtxbuf(struct ath_softc *, const struct ath_buf *bf,
        u_int qnum, u_int ix, int done);
#else
#define IFF_DUMPPKTS(sc, m) \
        ((sc->sc_ifp->if_flags & (IFF_DEBUG|IFF_LINK2)) == (IFF_DEBUG|IFF_LINK2))
#define DPRINTF(sc, m, fmt, ...) do {                           \
        (void) sc;                                              \
} while (0)
#define KEYPRINTF(sc, k, ix, mac) do {                          \
        (void) sc;                                              \
} while (0)
#endif

MALLOC_DEFINE(M_ATHDEV, "athdev", "ath driver dma buffers");

int
ath_attach(u_int16_t devid, struct ath_softc *sc)
{
        struct ifnet *ifp;
        struct ieee80211com *ic;
        struct ath_hal *ah = NULL;
        HAL_STATUS status;
        int error = 0, i;
        u_int wmodes;
        uint8_t macaddr[IEEE80211_ADDR_LEN];

        DPRINTF(sc, ATH_DEBUG_ANY, "%s: devid 0x%x\n", __func__, devid);

        ifp = sc->sc_ifp = if_alloc(IFT_IEEE80211);
        if (ifp == NULL) {
                device_printf(sc->sc_dev, "can not if_alloc()\n");
                error = ENOSPC;
                goto bad;
        }
        ic = ifp->if_l2com;

        /* set these up early for if_printf use */
        if_initname(ifp, device_get_name(sc->sc_dev),
                device_get_unit(sc->sc_dev));

        /* prepare sysctl tree for use in sub modules */
        sysctl_ctx_init(&sc->sc_sysctl_ctx);
        sc->sc_sysctl_tree = SYSCTL_ADD_NODE(&sc->sc_sysctl_ctx,
                SYSCTL_STATIC_CHILDREN(_hw),
                OID_AUTO,
                device_get_nameunit(sc->sc_dev),
                CTLFLAG_RD, 0, "");

        ah = ath_hal_attach(devid, sc, sc->sc_st, sc->sc_sh, &status);
        if (ah == NULL) {
                if_printf(ifp, "unable to attach hardware; HAL status %u\n",
                        status);
                error = ENXIO;
                goto bad;
        }
        sc->sc_ah = ah;
        sc->sc_invalid = 0;     /* ready to go, enable interrupt handling */
#ifdef  ATH_DEBUG
        sc->sc_debug = ath_debug;
#endif

        /*
         * Check if the MAC has multi-rate retry support.
         * We do this by trying to setup a fake extended
         * descriptor.  MAC's that don't have support will
         * return false w/o doing anything.  MAC's that do
         * support it will return true w/o doing anything.
         */
        sc->sc_mrretry = ath_hal_setupxtxdesc(ah, NULL, 0,0, 0,0, 0,0);

        /*
         * Check if the device has hardware counters for PHY
         * errors.  If so we need to enable the MIB interrupt
         * so we can act on stat triggers.
         */
        if (ath_hal_hwphycounters(ah))
                sc->sc_needmib = 1;

        /*
         * Get the hardware key cache size.
         */
        sc->sc_keymax = ath_hal_keycachesize(ah);
        if (sc->sc_keymax > ATH_KEYMAX) {
                if_printf(ifp, "Warning, using only %u of %u key cache slots\n",
                        ATH_KEYMAX, sc->sc_keymax);
                sc->sc_keymax = ATH_KEYMAX;
        }
        /*
         * Reset the key cache since some parts do not
         * reset the contents on initial power up.
         */
        for (i = 0; i < sc->sc_keymax; i++)
                ath_hal_keyreset(ah, i);

        /*
         * Collect the default channel list.
         */
        error = ath_getchannels(sc);
        if (error != 0)
                goto bad;

        /*
         * Setup rate tables for all potential media types.
         */
        ath_rate_setup(sc, IEEE80211_MODE_11A);
        ath_rate_setup(sc, IEEE80211_MODE_11B);
        ath_rate_setup(sc, IEEE80211_MODE_11G);
        ath_rate_setup(sc, IEEE80211_MODE_TURBO_A);
        ath_rate_setup(sc, IEEE80211_MODE_TURBO_G);
        ath_rate_setup(sc, IEEE80211_MODE_STURBO_A);
        ath_rate_setup(sc, IEEE80211_MODE_11NA);
        ath_rate_setup(sc, IEEE80211_MODE_11NG);
        ath_rate_setup(sc, IEEE80211_MODE_HALF);
        ath_rate_setup(sc, IEEE80211_MODE_QUARTER);

        /* NB: setup here so ath_rate_update is happy */
        ath_setcurmode(sc, IEEE80211_MODE_11A);

        /*
         * Allocate tx+rx descriptors and populate the lists.
         */
        wlan_assert_serialized();
        wlan_serialize_exit();
        error = ath_desc_alloc(sc);
        wlan_serialize_enter();
        if (error != 0) {
                if_printf(ifp, "failed to allocate descriptors: %d\n", error);
                goto bad;
        }
        callout_init(&sc->sc_cal_ch);
        callout_init(&sc->sc_wd_ch);

        sc->sc_tq = taskqueue_create("ath_taskq", M_INTWAIT,
                taskqueue_thread_enqueue, &sc->sc_tq);
        taskqueue_start_threads(&sc->sc_tq, 1, TDPRI_KERN_DAEMON, -1,
                "%s taskq", ifp->if_xname);

        TASK_INIT(&sc->sc_rxtask, 0, ath_rx_task, sc);
        TASK_INIT(&sc->sc_bmisstask, 0, ath_bmiss_task, sc);
        TASK_INIT(&sc->sc_bstucktask,0, ath_bstuck_task, sc);

        /*
         * Allocate hardware transmit queues: one queue for
         * beacon frames and one data queue for each QoS
         * priority.  Note that the hal handles reseting
         * these queues at the needed time.
         *
         * XXX PS-Poll
         */
        sc->sc_bhalq = ath_beaconq_setup(ah);
        if (sc->sc_bhalq == (u_int) -1) {
                if_printf(ifp, "unable to setup a beacon xmit queue!\n");
                error = EIO;
                goto bad2;
        }
        sc->sc_cabq = ath_txq_setup(sc, HAL_TX_QUEUE_CAB, 0);
        if (sc->sc_cabq == NULL) {
                if_printf(ifp, "unable to setup CAB xmit queue!\n");
                error = EIO;
                goto bad2;
        }
        /* NB: insure BK queue is the lowest priority h/w queue */
        if (!ath_tx_setup(sc, WME_AC_BK, HAL_WME_AC_BK)) {
                if_printf(ifp, "unable to setup xmit queue for %s traffic!\n",
                        ieee80211_wme_acnames[WME_AC_BK]);
                error = EIO;
                goto bad2;
        }
        if (!ath_tx_setup(sc, WME_AC_BE, HAL_WME_AC_BE) ||
            !ath_tx_setup(sc, WME_AC_VI, HAL_WME_AC_VI) ||
            !ath_tx_setup(sc, WME_AC_VO, HAL_WME_AC_VO)) {
                /*
                 * Not enough hardware tx queues to properly do WME;
                 * just punt and assign them all to the same h/w queue.
                 * We could do a better job of this if, for example,
                 * we allocate queues when we switch from station to
                 * AP mode.
                 */
                if (sc->sc_ac2q[WME_AC_VI] != NULL)
                        ath_tx_cleanupq(sc, sc->sc_ac2q[WME_AC_VI]);
                if (sc->sc_ac2q[WME_AC_BE] != NULL)
                        ath_tx_cleanupq(sc, sc->sc_ac2q[WME_AC_BE]);
                sc->sc_ac2q[WME_AC_BE] = sc->sc_ac2q[WME_AC_BK];
                sc->sc_ac2q[WME_AC_VI] = sc->sc_ac2q[WME_AC_BK];
                sc->sc_ac2q[WME_AC_VO] = sc->sc_ac2q[WME_AC_BK];
        }

        /*
         * Special case certain configurations.  Note the
         * CAB queue is handled by these specially so don't
         * include them when checking the txq setup mask.
         */
        switch (sc->sc_txqsetup &~ (1<<sc->sc_cabq->axq_qnum)) {
        case 0x01:
                TASK_INIT(&sc->sc_txtask, 0, ath_tx_task_q0, sc);
                break;
        case 0x0f:
                TASK_INIT(&sc->sc_txtask, 0, ath_tx_task_q0123, sc);
                break;
        default:
                TASK_INIT(&sc->sc_txtask, 0, ath_tx_task, sc);
                break;
        }

        /*
         * Setup rate control.  Some rate control modules
         * call back to change the anntena state so expose
         * the necessary entry points.
         * XXX maybe belongs in struct ath_ratectrl?
         */
        sc->sc_setdefantenna = ath_setdefantenna;
        sc->sc_rc = ath_rate_attach(sc);
        if (sc->sc_rc == NULL) {
                error = EIO;
                goto bad2;
        }

        sc->sc_blinking = 0;
        sc->sc_ledstate = 1;
        sc->sc_ledon = 0;                       /* low true */
        sc->sc_ledidle = (2700*hz)/1000;        /* 2.7sec */
        callout_init_mp(&sc->sc_ledtimer);
        /*
         * Auto-enable soft led processing for IBM cards and for
         * 5211 minipci cards.  Users can also manually enable/disable
         * support with a sysctl.
         */
        sc->sc_softled = (devid == AR5212_DEVID_IBM || devid == AR5211_DEVID);
        if (sc->sc_softled) {
                ath_hal_gpioCfgOutput(ah, sc->sc_ledpin,
                    HAL_GPIO_MUX_MAC_NETWORK_LED);
                ath_hal_gpioset(ah, sc->sc_ledpin, !sc->sc_ledon);
        }

        ifp->if_softc = sc;
        ifp->if_flags = IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST;
        ifp->if_start = ath_start;
        ifp->if_ioctl = ath_ioctl;
        ifp->if_init = ath_init;
        ifq_set_maxlen(&ifp->if_snd, IFQ_MAXLEN);
        ifq_set_ready(&ifp->if_snd);

        ic->ic_ifp = ifp;
        /* XXX not right but it's not used anywhere important */
        ic->ic_phytype = IEEE80211_T_OFDM;
        ic->ic_opmode = IEEE80211_M_STA;
        ic->ic_caps =
                  IEEE80211_C_STA               /* station mode */
                | IEEE80211_C_IBSS              /* ibss, nee adhoc, mode */
                | IEEE80211_C_HOSTAP            /* hostap mode */
                | IEEE80211_C_MONITOR           /* monitor mode */
                | IEEE80211_C_AHDEMO            /* adhoc demo mode */
                | IEEE80211_C_WDS               /* 4-address traffic works */
                | IEEE80211_C_MBSS              /* mesh point link mode */
                | IEEE80211_C_SHPREAMBLE        /* short preamble supported */
                | IEEE80211_C_SHSLOT            /* short slot time supported */
                | IEEE80211_C_WPA               /* capable of WPA1+WPA2 */
                | IEEE80211_C_BGSCAN            /* capable of bg scanning */
                | IEEE80211_C_TXFRAG            /* handle tx frags */
                ;
        /*
         * Query the hal to figure out h/w crypto support.
         */
        if (ath_hal_ciphersupported(ah, HAL_CIPHER_WEP))
                ic->ic_cryptocaps |= IEEE80211_CRYPTO_WEP;
        if (ath_hal_ciphersupported(ah, HAL_CIPHER_AES_OCB))
                ic->ic_cryptocaps |= IEEE80211_CRYPTO_AES_OCB;
        if (ath_hal_ciphersupported(ah, HAL_CIPHER_AES_CCM))
                ic->ic_cryptocaps |= IEEE80211_CRYPTO_AES_CCM;
        if (ath_hal_ciphersupported(ah, HAL_CIPHER_CKIP))
                ic->ic_cryptocaps |= IEEE80211_CRYPTO_CKIP;
        if (ath_hal_ciphersupported(ah, HAL_CIPHER_TKIP)) {
                ic->ic_cryptocaps |= IEEE80211_CRYPTO_TKIP;
                /*
                 * Check if h/w does the MIC and/or whether the
                 * separate key cache entries are required to
                 * handle both tx+rx MIC keys.
                 */
                if (ath_hal_ciphersupported(ah, HAL_CIPHER_MIC))
                        ic->ic_cryptocaps |= IEEE80211_CRYPTO_TKIPMIC;
                /*
                 * If the h/w supports storing tx+rx MIC keys
                 * in one cache slot automatically enable use.
                 */
                if (ath_hal_hastkipsplit(ah) ||
                    !ath_hal_settkipsplit(ah, AH_FALSE))
                        sc->sc_splitmic = 1;
                /*
                 * If the h/w can do TKIP MIC together with WME then
                 * we use it; otherwise we force the MIC to be done
                 * in software by the net80211 layer.
                 */
                if (ath_hal_haswmetkipmic(ah))
                        sc->sc_wmetkipmic = 1;
        }
        sc->sc_hasclrkey = ath_hal_ciphersupported(ah, HAL_CIPHER_CLR);
        /*
         * Check for multicast key search support.
         */
        if (ath_hal_hasmcastkeysearch(sc->sc_ah) &&
            !ath_hal_getmcastkeysearch(sc->sc_ah)) {
                ath_hal_setmcastkeysearch(sc->sc_ah, 1);
        }
        sc->sc_mcastkey = ath_hal_getmcastkeysearch(ah);
        /*
         * Mark key cache slots associated with global keys
         * as in use.  If we knew TKIP was not to be used we
         * could leave the +32, +64, and +32+64 slots free.
         */
        for (i = 0; i < IEEE80211_WEP_NKID; i++) {
                setbit(sc->sc_keymap, i);
                setbit(sc->sc_keymap, i+64);
                if (sc->sc_splitmic) {
                        setbit(sc->sc_keymap, i+32);
                        setbit(sc->sc_keymap, i+32+64);
                }
        }
        /*
         * TPC support can be done either with a global cap or
         * per-packet support.  The latter is not available on
         * all parts.  We're a bit pedantic here as all parts
         * support a global cap.
         */
        if (ath_hal_hastpc(ah) || ath_hal_hastxpowlimit(ah))
                ic->ic_caps |= IEEE80211_C_TXPMGT;

        /*
         * Mark WME capability only if we have sufficient
         * hardware queues to do proper priority scheduling.
         */
        if (sc->sc_ac2q[WME_AC_BE] != sc->sc_ac2q[WME_AC_BK])
                ic->ic_caps |= IEEE80211_C_WME;
        /*
         * Check for misc other capabilities.
         */
        if (ath_hal_hasbursting(ah))
                ic->ic_caps |= IEEE80211_C_BURST;
        sc->sc_hasbmask = ath_hal_hasbssidmask(ah);
        sc->sc_hasbmatch = ath_hal_hasbssidmatch(ah);
        sc->sc_hastsfadd = ath_hal_hastsfadjust(ah);
        if (ath_hal_hasfastframes(ah))
                ic->ic_caps |= IEEE80211_C_FF;
        wmodes = ath_hal_getwirelessmodes(ah);
        if (wmodes & (HAL_MODE_108G|HAL_MODE_TURBO))
                ic->ic_caps |= IEEE80211_C_TURBOP;
#ifdef IEEE80211_SUPPORT_TDMA
        if (ath_hal_macversion(ah) > 0x78) {
                ic->ic_caps |= IEEE80211_C_TDMA; /* capable of TDMA */
                ic->ic_tdma_update = ath_tdma_update;
        }
#endif
        /*
         * Indicate we need the 802.11 header padded to a
         * 32-bit boundary for 4-address and QoS frames.
         */
        ic->ic_flags |= IEEE80211_F_DATAPAD;

        /*
         * Query the hal about antenna support.
         */
        sc->sc_defant = ath_hal_getdefantenna(ah);

        /*
         * Not all chips have the VEOL support we want to
         * use with IBSS beacons; check here for it.
         */
        sc->sc_hasveol = ath_hal_hasveol(ah);

        /* get mac address from hardware */
        ath_hal_getmac(ah, macaddr);
        if (sc->sc_hasbmask)
                ath_hal_getbssidmask(ah, sc->sc_hwbssidmask);

        /* NB: used to size node table key mapping array */
        ic->ic_max_keyix = sc->sc_keymax;
        /* call MI attach routine. */
        ieee80211_ifattach(ic, macaddr);
        ic->ic_setregdomain = ath_setregdomain;
        ic->ic_getradiocaps = ath_getradiocaps;
        sc->sc_opmode = HAL_M_STA;

        /* override default methods */
        ic->ic_newassoc = ath_newassoc;
        ic->ic_updateslot = ath_updateslot;
        ic->ic_wme.wme_update = ath_wme_update;
        ic->ic_vap_create = ath_vap_create;
        ic->ic_vap_delete = ath_vap_delete;
        ic->ic_raw_xmit = ath_raw_xmit;
        ic->ic_update_mcast = ath_update_mcast;
        ic->ic_update_promisc = ath_update_promisc;
        ic->ic_node_alloc = ath_node_alloc;
        sc->sc_node_free = ic->ic_node_free;
        ic->ic_node_free = ath_node_free;
        ic->ic_node_getsignal = ath_node_getsignal;
        ic->ic_scan_start = ath_scan_start;
        ic->ic_scan_end = ath_scan_end;
        ic->ic_set_channel = ath_set_channel;

        ieee80211_radiotap_attach(ic,
            &sc->sc_tx_th.wt_ihdr, sizeof(sc->sc_tx_th),
                ATH_TX_RADIOTAP_PRESENT,
            &sc->sc_rx_th.wr_ihdr, sizeof(sc->sc_rx_th),
                ATH_RX_RADIOTAP_PRESENT);

        /*
         * Setup dynamic sysctl's now that country code and
         * regdomain are available from the hal.
         */
        ath_sysctlattach(sc);
        ath_sysctl_stats_attach(sc);

        if (bootverbose)
                ieee80211_announce(ic);
        ath_announce(sc);
        return 0;
bad2:
        ath_tx_cleanup(sc);
        ath_desc_free(sc);
bad:
        if (ah)
                ath_hal_detach(ah);
        if (ifp != NULL)
                if_free(ifp);
        sc->sc_invalid = 1;
        return error;
}

int
ath_detach(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;

        DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
                __func__, ifp->if_flags);

        /* 
         * NB: the order of these is important:
         * o stop the chip so no more interrupts will fire
         * o call the 802.11 layer before detaching the hal to
         *   insure callbacks into the driver to delete global
         *   key cache entries can be handled
         * o free the taskqueue which drains any pending tasks
         * o reclaim the tx queue data structures after calling
         *   the 802.11 layer as we'll get called back to reclaim
         *   node state and potentially want to use them
         * o to cleanup the tx queues the hal is called, so detach
         *   it last
         * Other than that, it's straightforward...
         */
        ath_stop(ifp);
        ieee80211_ifdetach(ifp->if_l2com);
        taskqueue_free(sc->sc_tq);
#ifdef ATH_TX99_DIAG
        if (sc->sc_tx99 != NULL)
                sc->sc_tx99->detach(sc->sc_tx99);
#endif
        ath_rate_detach(sc->sc_rc);
        ath_desc_free(sc);
        ath_tx_cleanup(sc);
        ath_hal_detach(sc->sc_ah);      /* NB: sets chip in full sleep */
        if (sc->sc_sysctl_tree) {
                sysctl_ctx_free(&sc->sc_sysctl_ctx);
                sc->sc_sysctl_tree = NULL;
        }
        if_free(ifp);

        return 0;
}

/*
 * MAC address handling for multiple BSS on the same radio.
 * The first vap uses the MAC address from the EEPROM.  For
 * subsequent vap's we set the U/L bit (bit 1) in the MAC
 * address and use the next six bits as an index.
 */
static void
assign_address(struct ath_softc *sc, uint8_t mac[IEEE80211_ADDR_LEN], int clone)
{
        int i;

        if (clone && sc->sc_hasbmask) {
                /* NB: we only do this if h/w supports multiple bssid */
                for (i = 0; i < 8; i++)
                        if ((sc->sc_bssidmask & (1<<i)) == 0)
                                break;
                if (i != 0)
                        mac[0] |= (i << 2)|0x2;
        } else
                i = 0;
        sc->sc_bssidmask |= 1<<i;
        sc->sc_hwbssidmask[0] &= ~mac[0];
        if (i == 0)
                sc->sc_nbssid0++;
}

static void
reclaim_address(struct ath_softc *sc, const uint8_t mac[IEEE80211_ADDR_LEN])
{
        int i = mac[0] >> 2;
        uint8_t mask;

        if (i != 0 || --sc->sc_nbssid0 == 0) {
                sc->sc_bssidmask &= ~(1<<i);
                /* recalculate bssid mask from remaining addresses */
                mask = 0xff;
                for (i = 1; i < 8; i++)
                        if (sc->sc_bssidmask & (1<<i))
                                mask &= ~((i<<2)|0x2);
                sc->sc_hwbssidmask[0] |= mask;
        }
}

/*
 * Assign a beacon xmit slot.  We try to space out
 * assignments so when beacons are staggered the
 * traffic coming out of the cab q has maximal time
 * to go out before the next beacon is scheduled.
 */
static int
assign_bslot(struct ath_softc *sc)
{
        u_int slot, free;

        free = 0;
        for (slot = 0; slot < ATH_BCBUF; slot++)
                if (sc->sc_bslot[slot] == NULL) {
                        if (sc->sc_bslot[(slot+1)%ATH_BCBUF] == NULL &&
                            sc->sc_bslot[(slot-1)%ATH_BCBUF] == NULL)
                                return slot;
                        free = slot;
                        /* NB: keep looking for a double slot */
                }
        return free;
}

static struct ieee80211vap *
ath_vap_create(struct ieee80211com *ic,
        const char name[IFNAMSIZ], int unit, int opmode, int flags,
        const uint8_t bssid[IEEE80211_ADDR_LEN],
        const uint8_t mac0[IEEE80211_ADDR_LEN])
{
        struct ath_softc *sc = ic->ic_ifp->if_softc;
        struct ath_vap *avp;
        struct ieee80211vap *vap;
        uint8_t mac[IEEE80211_ADDR_LEN];
        int ic_opmode, needbeacon, error;

        avp = (struct ath_vap *) kmalloc(sizeof(struct ath_vap),
            M_80211_VAP, M_WAITOK | M_ZERO);
        needbeacon = 0;
        IEEE80211_ADDR_COPY(mac, mac0);

        ic_opmode = opmode;             /* default to opmode of new vap */
        switch (opmode) {
        case IEEE80211_M_STA:
                if (sc->sc_nstavaps != 0) {     /* XXX only 1 for now */
                        device_printf(sc->sc_dev, "only 1 sta vap supported\n");
                        goto bad;
                }
                if (sc->sc_nvaps) {
                        /*
                         * With multiple vaps we must fall back
                         * to s/w beacon miss handling.
                         */
                        flags |= IEEE80211_CLONE_NOBEACONS;
                }
                if (flags & IEEE80211_CLONE_NOBEACONS) {
                        /*
                         * Station mode w/o beacons are implemented w/ AP mode.
                         */
                        ic_opmode = IEEE80211_M_HOSTAP;
                }
                break;
        case IEEE80211_M_IBSS:
                if (sc->sc_nvaps != 0) {        /* XXX only 1 for now */
                        device_printf(sc->sc_dev,
                            "only 1 ibss vap supported\n");
                        goto bad;
                }
                needbeacon = 1;
                break;
        case IEEE80211_M_AHDEMO:
#ifdef IEEE80211_SUPPORT_TDMA
                if (flags & IEEE80211_CLONE_TDMA) {
                        if (sc->sc_nvaps != 0) {
                                device_printf(sc->sc_dev,
                                    "only 1 tdma vap supported\n");
                                goto bad;
                        }
                        needbeacon = 1;
                        flags |= IEEE80211_CLONE_NOBEACONS;
                }
                /* fall thru... */
#endif
        case IEEE80211_M_MONITOR:
                if (sc->sc_nvaps != 0 && ic->ic_opmode != opmode) {
                        /*
                         * Adopt existing mode.  Adding a monitor or ahdemo
                         * vap to an existing configuration is of dubious
                         * value but should be ok.
                         */
                        /* XXX not right for monitor mode */
                        ic_opmode = ic->ic_opmode;
                }
                break;
        case IEEE80211_M_HOSTAP:
        case IEEE80211_M_MBSS:
                needbeacon = 1;
                break;
        case IEEE80211_M_WDS:
                if (sc->sc_nvaps != 0 && ic->ic_opmode == IEEE80211_M_STA) {
                        device_printf(sc->sc_dev,
                            "wds not supported in sta mode\n");
                        goto bad;
                }
                /*
                 * Silently remove any request for a unique
                 * bssid; WDS vap's always share the local
                 * mac address.
                 */
                flags &= ~IEEE80211_CLONE_BSSID;
                if (sc->sc_nvaps == 0)
                        ic_opmode = IEEE80211_M_HOSTAP;
                else
                        ic_opmode = ic->ic_opmode;
                break;
        default:
                device_printf(sc->sc_dev, "unknown opmode %d\n", opmode);
                goto bad;
        }
        /*
         * Check that a beacon buffer is available; the code below assumes it.
         */
        if (needbeacon & STAILQ_EMPTY(&sc->sc_bbuf)) {
                device_printf(sc->sc_dev, "no beacon buffer available\n");
                goto bad;
        }

        /* STA, AHDEMO? */
        if (opmode == IEEE80211_M_HOSTAP || opmode == IEEE80211_M_MBSS) {
                assign_address(sc, mac, flags & IEEE80211_CLONE_BSSID);
                ath_hal_setbssidmask(sc->sc_ah, sc->sc_hwbssidmask);
        }

        vap = &avp->av_vap;
        /* XXX can't hold mutex across if_alloc */
        error = ieee80211_vap_setup(ic, vap, name, unit, opmode, flags,
            bssid, mac);
        if (error != 0) {
                device_printf(sc->sc_dev, "%s: error %d creating vap\n",
                    __func__, error);
                goto bad2;
        }

        /* h/w crypto support */
        vap->iv_key_alloc = ath_key_alloc;
        vap->iv_key_delete = ath_key_delete;
        vap->iv_key_set = ath_key_set;
        vap->iv_key_update_begin = ath_key_update_begin;
        vap->iv_key_update_end = ath_key_update_end;

        /* override various methods */
        avp->av_recv_mgmt = vap->iv_recv_mgmt;
        vap->iv_recv_mgmt = ath_recv_mgmt;
        vap->iv_reset = ath_reset_vap;
        vap->iv_update_beacon = ath_beacon_update;
        avp->av_newstate = vap->iv_newstate;
        vap->iv_newstate = ath_newstate;
        avp->av_bmiss = vap->iv_bmiss;
        vap->iv_bmiss = ath_bmiss_vap;

        avp->av_bslot = -1;
        if (needbeacon) {
                /*
                 * Allocate beacon state and setup the q for buffered
                 * multicast frames.  We know a beacon buffer is
                 * available because we checked above.
                 */
                avp->av_bcbuf = STAILQ_FIRST(&sc->sc_bbuf);
                STAILQ_REMOVE_HEAD(&sc->sc_bbuf, bf_list);
                if (opmode != IEEE80211_M_IBSS || !sc->sc_hasveol) {
                        /*
                         * Assign the vap to a beacon xmit slot.  As above
                         * this cannot fail to find a free one.
                         */
                        avp->av_bslot = assign_bslot(sc);
                        KASSERT(sc->sc_bslot[avp->av_bslot] == NULL,
                            ("beacon slot %u not empty", avp->av_bslot));
                        sc->sc_bslot[avp->av_bslot] = vap;
                        sc->sc_nbcnvaps++;
                }
                if (sc->sc_hastsfadd && sc->sc_nbcnvaps > 0) {
                        /*
                         * Multple vaps are to transmit beacons and we
                         * have h/w support for TSF adjusting; enable
                         * use of staggered beacons.
                         */
                        sc->sc_stagbeacons = 1;
                }
                ath_txq_init(sc, &avp->av_mcastq, ATH_TXQ_SWQ);
        }

        ic->ic_opmode = ic_opmode;
        if (opmode != IEEE80211_M_WDS) {
                sc->sc_nvaps++;
                if (opmode == IEEE80211_M_STA)
                        sc->sc_nstavaps++;
                if (opmode == IEEE80211_M_MBSS)
                        sc->sc_nmeshvaps++;
        }
        switch (ic_opmode) {
        case IEEE80211_M_IBSS:
                sc->sc_opmode = HAL_M_IBSS;
                break;
        case IEEE80211_M_STA:
                sc->sc_opmode = HAL_M_STA;
                break;
        case IEEE80211_M_AHDEMO:
#ifdef IEEE80211_SUPPORT_TDMA
                if (vap->iv_caps & IEEE80211_C_TDMA) {
                        sc->sc_tdma = 1;
                        /* NB: disable tsf adjust */
                        sc->sc_stagbeacons = 0;
                }
                /*
                 * NB: adhoc demo mode is a pseudo mode; to the hal it's
                 * just ap mode.
                 */
                /* fall thru... */
#endif
        case IEEE80211_M_HOSTAP:
        case IEEE80211_M_MBSS:
                sc->sc_opmode = HAL_M_HOSTAP;
                break;
        case IEEE80211_M_MONITOR:
                sc->sc_opmode = HAL_M_MONITOR;
                break;
        default:
                /* XXX should not happen */
                break;
        }
        if (sc->sc_hastsfadd) {
                /*
                 * Configure whether or not TSF adjust should be done.
                 */
                ath_hal_settsfadjust(sc->sc_ah, sc->sc_stagbeacons);
        }
        if (flags & IEEE80211_CLONE_NOBEACONS) {
                /*
                 * Enable s/w beacon miss handling.
                 */
                sc->sc_swbmiss = 1;
        }

        /* complete setup */
        ieee80211_vap_attach(vap, ath_media_change, ieee80211_media_status);
        return vap;
bad2:
        reclaim_address(sc, mac);
        ath_hal_setbssidmask(sc->sc_ah, sc->sc_hwbssidmask);
bad:
        kfree(avp, M_80211_VAP);
        return NULL;
}

static void
ath_vap_delete(struct ieee80211vap *vap)
{
        struct ieee80211com *ic = vap->iv_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;
        struct ath_vap *avp = ATH_VAP(vap);

        if (ifp->if_flags & IFF_RUNNING) {
                /*
                 * Quiesce the hardware while we remove the vap.  In
                 * particular we need to reclaim all references to
                 * the vap state by any frames pending on the tx queues.
                 */
                ath_hal_intrset(ah, 0);         /* disable interrupts */
                ath_draintxq(sc);               /* stop xmit side */
                ath_stoprecv(sc);               /* stop recv side */
        }

        ieee80211_vap_detach(vap);
        /*
         * Reclaim beacon state.  Note this must be done before
         * the vap instance is reclaimed as we may have a reference
         * to it in the buffer for the beacon frame.
         */
        if (avp->av_bcbuf != NULL) {
                if (avp->av_bslot != -1) {
                        sc->sc_bslot[avp->av_bslot] = NULL;
                        sc->sc_nbcnvaps--;
                }
                ath_beacon_return(sc, avp->av_bcbuf);
                avp->av_bcbuf = NULL;
                if (sc->sc_nbcnvaps == 0) {
                        sc->sc_stagbeacons = 0;
                        if (sc->sc_hastsfadd)
                                ath_hal_settsfadjust(sc->sc_ah, 0);
                }
                /*
                 * Reclaim any pending mcast frames for the vap.
                 */
                ath_tx_draintxq(sc, &avp->av_mcastq);
        }
        /*
         * Update bookkeeping.
         */
        if (vap->iv_opmode == IEEE80211_M_STA) {
                sc->sc_nstavaps--;
                if (sc->sc_nstavaps == 0 && sc->sc_swbmiss)
                        sc->sc_swbmiss = 0;
        } else if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
            vap->iv_opmode == IEEE80211_M_MBSS) {
                reclaim_address(sc, vap->iv_myaddr);
                ath_hal_setbssidmask(ah, sc->sc_hwbssidmask);
                if (vap->iv_opmode == IEEE80211_M_MBSS)
                        sc->sc_nmeshvaps--;
        }
        if (vap->iv_opmode != IEEE80211_M_WDS)
                sc->sc_nvaps--;
#ifdef IEEE80211_SUPPORT_TDMA
        /* TDMA operation ceases when the last vap is destroyed */
        if (sc->sc_tdma && sc->sc_nvaps == 0) {
                sc->sc_tdma = 0;
                sc->sc_swbmiss = 0;
        }
#endif
        kfree(avp, M_80211_VAP);

        if (ifp->if_flags & IFF_RUNNING) {
                /*
                 * Restart rx+tx machines if still running (RUNNING will
                 * be reset if we just destroyed the last vap).
                 */
                if (ath_startrecv(sc) != 0)
                        if_printf(ifp, "%s: unable to restart recv logic\n",
                            __func__);
                if (sc->sc_beacons) {           /* restart beacons */
#ifdef IEEE80211_SUPPORT_TDMA
                        if (sc->sc_tdma)
                                ath_tdma_config(sc, NULL);
                        else
#endif
                                ath_beacon_config(sc, NULL);
                }
                ath_hal_intrset(ah, sc->sc_imask);
        }
}

void
ath_suspend(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;

        DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
                __func__, ifp->if_flags);

        sc->sc_resume_up = (ifp->if_flags & IFF_UP) != 0;
        if (ic->ic_opmode == IEEE80211_M_STA)
                ath_stop(ifp);
        else
                ieee80211_suspend_all(ic);
        /*
         * NB: don't worry about putting the chip in low power
         * mode; pci will power off our socket on suspend and
         * CardBus detaches the device.
         */
}

/*
 * Reset the key cache since some parts do not reset the
 * contents on resume.  First we clear all entries, then
 * re-load keys that the 802.11 layer assumes are setup
 * in h/w.
 */
static void
ath_reset_keycache(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        int i;

        for (i = 0; i < sc->sc_keymax; i++)
                ath_hal_keyreset(ah, i);
        ieee80211_crypto_reload_keys(ic);
}

void
ath_resume(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        HAL_STATUS status;

        DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
                __func__, ifp->if_flags);

        /*
         * Must reset the chip before we reload the
         * keycache as we were powered down on suspend.
         */
        ath_hal_reset(ah, sc->sc_opmode,
            sc->sc_curchan != NULL ? sc->sc_curchan : ic->ic_curchan,
            AH_FALSE, &status);
        ath_reset_keycache(sc);
        if (sc->sc_resume_up) {
                if (ic->ic_opmode == IEEE80211_M_STA) {
                        ath_init(sc);
                        /*
                         * Program the beacon registers using the last rx'd
                         * beacon frame and enable sync on the next beacon
                         * we see.  This should handle the case where we
                         * wakeup and find the same AP and also the case where
                         * we wakeup and need to roam.  For the latter we
                         * should get bmiss events that trigger a roam.
                         */
                        ath_beacon_config(sc, NULL);
                        sc->sc_syncbeacon = 1;
                } else
                        ieee80211_resume_all(ic);
        }
        if (sc->sc_softled) {
                ath_hal_gpioCfgOutput(ah, sc->sc_ledpin,
                    HAL_GPIO_MUX_MAC_NETWORK_LED);
                ath_hal_gpioset(ah, sc->sc_ledpin, !sc->sc_ledon);
        }
}

void
ath_shutdown(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;

        DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
                __func__, ifp->if_flags);

        ath_stop(ifp);
        /* NB: no point powering down chip as we're about to reboot */
}

/*
 * Interrupt handler.  Most of the actual processing is deferred.
 */
void
ath_intr(void *arg)
{
        struct ath_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ifp;
        struct ath_hal *ah = sc->sc_ah;
        HAL_INT status;
        HAL_INT ostatus;

        if (sc->sc_invalid) {
                /*
                 * The hardware is not ready/present, don't touch anything.
                 * Note this can happen early on if the IRQ is shared.
                 */
                DPRINTF(sc, ATH_DEBUG_ANY, "%s: invalid; ignored\n", __func__);
                return;
        }

        if (!ath_hal_intrpend(ah))              /* shared irq, not for us */
                return;
        if ((ifp->if_flags & IFF_UP) == 0 ||
            (ifp->if_flags & IFF_RUNNING) == 0) {
                HAL_INT status;

                DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags 0x%x\n",
                        __func__, ifp->if_flags);
                ath_hal_getisr(ah, &status);    /* clear ISR */
                ath_hal_intrset(ah, 0);         /* disable further intr's */
                return;
        }
        /*
         * Figure out the reason(s) for the interrupt.  Note
         * that the hal returns a pseudo-ISR that may include
         * bits we haven't explicitly enabled so we mask the
         * value to insure we only process bits we requested.
         */
        ath_hal_getisr(ah, &ostatus);           /* NB: clears ISR too */
        DPRINTF(sc, ATH_DEBUG_INTR, "%s: status 0x%x\n", __func__, ostatus);
        status = ostatus & sc->sc_imask;        /* discard unasked for bits */
        if (status & HAL_INT_FATAL) {
                sc->sc_stats.ast_hardware++;
                ath_hal_intrset(ah, 0);         /* disable intr's until reset */
                ath_fatal_proc(sc, 0);
        } else {
                if (status & HAL_INT_SWBA) {
                        /*
                         * Software beacon alert--time to send a beacon.
                         * Handle beacon transmission directly; deferring
                         * this is too slow to meet timing constraints
                         * under load.
                         */
#ifdef IEEE80211_SUPPORT_TDMA
                        if (sc->sc_tdma) {
                                if (sc->sc_tdmaswba == 0) {
                                        struct ieee80211com *ic = ifp->if_l2com;
                                        struct ieee80211vap *vap =
                                            TAILQ_FIRST(&ic->ic_vaps);
                                        ath_tdma_beacon_send(sc, vap);
                                        sc->sc_tdmaswba =
                                            vap->iv_tdma->tdma_bintval;
                                } else
                                        sc->sc_tdmaswba--;
                        } else
#endif
                        {
                                ath_beacon_proc(sc, 0);
#ifdef IEEE80211_SUPPORT_SUPERG
                                /*
                                 * Schedule the rx taskq in case there's no
                                 * traffic so any frames held on the staging
                                 * queue are aged and potentially flushed.
                                 */
                                taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
#endif
                        }
                }

                /*
                 * NB: The hardware should re-read the link when the RXE
                 *     bit is written, but it doesn't work at least on
                 *     older chipsets.
                 */
                if (status & HAL_INT_RXEOL) {
                        sc->sc_stats.ast_rxeol++;
                        sc->sc_rxlink = NULL;
                }

                if (status & HAL_INT_TXURN) {
                        sc->sc_stats.ast_txurn++;
                        /* bump tx trigger level */
                        ath_hal_updatetxtriglevel(ah, AH_TRUE);
                }

                if (status & HAL_INT_RX)
                        taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);

                if (status & HAL_INT_TX)
                        taskqueue_enqueue(sc->sc_tq, &sc->sc_txtask);

                if (status & HAL_INT_BMISS) {
                        sc->sc_stats.ast_bmiss++;
                        taskqueue_enqueue(sc->sc_tq, &sc->sc_bmisstask);
                }

                if (status & HAL_INT_MIB) {
                        sc->sc_stats.ast_mib++;
                        /*
                         * Disable interrupts until we service the MIB
                         * interrupt; otherwise it will continue to fire.
                         */
                        ath_hal_intrset(ah, 0);
                        /*
                         * Let the hal handle the event.  We assume it will
                         * clear whatever condition caused the interrupt.
                         */
                        ath_hal_mibevent(ah, &sc->sc_halstats);
                        ath_hal_intrset(ah, sc->sc_imask);
                }

                if (status & HAL_INT_RXORN) {
                        /* NB: hal marks HAL_INT_FATAL when RXORN is fatal */
                        sc->sc_stats.ast_rxorn++;
                }
        }
}

static void
ath_fatal_proc(void *arg, int pending)
{
        struct ath_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ifp;
        u_int32_t *state;
        u_int32_t len;
        void *sp;

        if_printf(ifp, "hardware error; resetting\n");
        /*
         * Fatal errors are unrecoverable.  Typically these
         * are caused by DMA errors.  Collect h/w state from
         * the hal so we can diagnose what's going on.
         */
        if (ath_hal_getfatalstate(sc->sc_ah, &sp, &len)) {
                KASSERT(len >= 6*sizeof(u_int32_t), ("len %u bytes", len));
                state = sp;
                if_printf(ifp, "0x%08x 0x%08x 0x%08x, 0x%08x 0x%08x 0x%08x\n",
                    state[0], state[1] , state[2], state[3],
                    state[4], state[5]);
        }
        ath_reset(ifp);
}

static void
ath_bmiss_vap(struct ieee80211vap *vap)
{
        /*
         * Workaround phantom bmiss interrupts by sanity-checking
         * the time of our last rx'd frame.  If it is within the
         * beacon miss interval then ignore the interrupt.  If it's
         * truly a bmiss we'll get another interrupt soon and that'll
         * be dispatched up for processing.  Note this applies only
         * for h/w beacon miss events.
         */
        if ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) == 0) {
                struct ifnet *ifp = vap->iv_ic->ic_ifp;
                struct ath_softc *sc = ifp->if_softc;
                u_int64_t lastrx = sc->sc_lastrx;
                u_int64_t tsf = ath_hal_gettsf64(sc->sc_ah);
                u_int bmisstimeout =
                        vap->iv_bmissthreshold * vap->iv_bss->ni_intval * 1024;

                DPRINTF(sc, ATH_DEBUG_BEACON,
                    "%s: tsf %llu lastrx %lld (%llu) bmiss %u\n",
                    __func__, (unsigned long long) tsf,
                    (unsigned long long)(tsf - lastrx),
                    (unsigned long long) lastrx, bmisstimeout);

                if (tsf - lastrx <= bmisstimeout) {
                        sc->sc_stats.ast_bmiss_phantom++;
                        return;
                }
        }
        ATH_VAP(vap)->av_bmiss(vap);
}

static int
ath_hal_gethangstate(struct ath_hal *ah, uint32_t mask, uint32_t *hangs)
{
        uint32_t rsize;
        void *sp;

        if (!ath_hal_getdiagstate(ah, 32, &mask, sizeof(mask), &sp, &rsize))
                return 0;
        KASSERT(rsize == sizeof(uint32_t), ("resultsize %u", rsize));
        *hangs = *(uint32_t *)sp;
        return 1;
}

static void
ath_bmiss_task(void *arg, int pending)
{
        struct ath_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ifp;
        uint32_t hangs;

        wlan_serialize_enter();
        DPRINTF(sc, ATH_DEBUG_ANY, "%s: pending %u\n", __func__, pending);

        if (ath_hal_gethangstate(sc->sc_ah, 0xff, &hangs) && hangs != 0) {
                if_printf(ifp, "bb hang detected (0x%x), reseting\n", hangs); 
                ath_reset(ifp);
        } else {
                ieee80211_beacon_miss(ifp->if_l2com);
        }
        wlan_serialize_exit();
}

/*
 * Handle TKIP MIC setup to deal hardware that doesn't do MIC
 * calcs together with WME.  If necessary disable the crypto
 * hardware and mark the 802.11 state so keys will be setup
 * with the MIC work done in software.
 */
static void
ath_settkipmic(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;

        if ((ic->ic_cryptocaps & IEEE80211_CRYPTO_TKIP) && !sc->sc_wmetkipmic) {
                if (ic->ic_flags & IEEE80211_F_WME) {
                        ath_hal_settkipmic(sc->sc_ah, AH_FALSE);
                        ic->ic_cryptocaps &= ~IEEE80211_CRYPTO_TKIPMIC;
                } else {
                        ath_hal_settkipmic(sc->sc_ah, AH_TRUE);
                        ic->ic_cryptocaps |= IEEE80211_CRYPTO_TKIPMIC;
                }
        }
}

static void
ath_init(void *arg)
{
        struct ath_softc *sc = (struct ath_softc *) arg;
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        HAL_STATUS status;

        DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags 0x%x\n",
                __func__, ifp->if_flags);

        /*
         * Stop anything previously setup.  This is safe
         * whether this is the first time through or not.
         */
        ath_stop_locked(ifp);

        /*
         * The basic interface to setting the hardware in a good
         * state is ``reset''.  On return the hardware is known to
         * be powered up and with interrupts disabled.  This must
         * be followed by initialization of the appropriate bits
         * and then setup of the interrupt mask.
         */
        ath_settkipmic(sc);
        if (!ath_hal_reset(ah, sc->sc_opmode, ic->ic_curchan, AH_FALSE, &status)) {
                if_printf(ifp, "unable to reset hardware; hal status %u\n",
                        status);
                return;
        }
        ath_chan_change(sc, ic->ic_curchan);

        /*
         * Likewise this is set during reset so update
         * state cached in the driver.
         */
        sc->sc_diversity = ath_hal_getdiversity(ah);
        sc->sc_lastlongcal = 0;
        sc->sc_resetcal = 1;
        sc->sc_lastcalreset = 0;

        /*
         * Setup the hardware after reset: the key cache
         * is filled as needed and the receive engine is
         * set going.  Frame transmit is handled entirely
         * in the frame output path; there's nothing to do
         * here except setup the interrupt mask.
         */
        if (ath_startrecv(sc) != 0) {
                if_printf(ifp, "unable to start recv logic\n");
                return;
        }

        /*
         * Enable interrupts.
         */
        sc->sc_imask = HAL_INT_RX | HAL_INT_TX
                  | HAL_INT_RXEOL | HAL_INT_RXORN
                  | HAL_INT_FATAL | HAL_INT_GLOBAL;
        /*
         * Enable MIB interrupts when there are hardware phy counters.
         * Note we only do this (at the moment) for station mode.
         */
        if (sc->sc_needmib && ic->ic_opmode == IEEE80211_M_STA)
                sc->sc_imask |= HAL_INT_MIB;

        ifp->if_flags |= IFF_RUNNING;
        callout_reset(&sc->sc_wd_ch, hz, ath_watchdog_callout, sc);
        ath_hal_intrset(ah, sc->sc_imask);


#ifdef ATH_TX99_DIAG
        if (sc->sc_tx99 != NULL)
                sc->sc_tx99->start(sc->sc_tx99);
        else
#endif
        ieee80211_start_all(ic);                /* start all vap's */
}

static void
ath_stop_locked(struct ifnet *ifp)
{
        struct ath_softc *sc = ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;

        DPRINTF(sc, ATH_DEBUG_ANY, "%s: invalid %u if_flags 0x%x\n",
                __func__, sc->sc_invalid, ifp->if_flags);

        if (ifp->if_flags & IFF_RUNNING) {
                /*
                 * Shutdown the hardware and driver:
                 *    reset 802.11 state machine
                 *    turn off timers
                 *    disable interrupts
                 *    turn off the radio
                 *    clear transmit machinery
                 *    clear receive machinery
                 *    drain and release tx queues
                 *    reclaim beacon resources
                 *    power down hardware
                 *
                 * Note that some of this work is not possible if the
                 * hardware is gone (invalid).
                 */
#ifdef ATH_TX99_DIAG
                if (sc->sc_tx99 != NULL)
                        sc->sc_tx99->stop(sc->sc_tx99);
#endif
                callout_stop(&sc->sc_wd_ch);
                sc->sc_wd_timer = 0;
                ifp->if_flags &= ~IFF_RUNNING;
                if (!sc->sc_invalid) {
                        if (sc->sc_softled) {
                                callout_stop(&sc->sc_ledtimer);
                                ath_hal_gpioset(ah, sc->sc_ledpin,
                                        !sc->sc_ledon);
                                sc->sc_blinking = 0;
                        }
                        ath_hal_intrset(ah, 0);
                }
                ath_draintxq(sc);
                if (!sc->sc_invalid) {
                        ath_stoprecv(sc);
                        ath_hal_phydisable(ah);
                } else
                        sc->sc_rxlink = NULL;
                ath_beacon_free(sc);    /* XXX not needed */
        }
}

static void
ath_stop(struct ifnet *ifp)
{
        struct ath_softc *sc __unused = ifp->if_softc;

        ath_stop_locked(ifp);
}

/*
 * Reset the hardware w/o losing operational state.  This is
 * basically a more efficient way of doing ath_stop, ath_init,
 * followed by state transitions to the current 802.11
 * operational state.  Used to recover from various errors and
 * to reset or reload hardware state.
 */
static int
ath_reset(struct ifnet *ifp)
{
        struct ath_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        HAL_STATUS status;

        ath_hal_intrset(ah, 0);         /* disable interrupts */
        ath_draintxq(sc);               /* stop xmit side */
        ath_stoprecv(sc);               /* stop recv side */
        ath_settkipmic(sc);             /* configure TKIP MIC handling */
        /* NB: indicate channel change so we do a full reset */
        if (!ath_hal_reset(ah, sc->sc_opmode, ic->ic_curchan, AH_TRUE, &status))
                if_printf(ifp, "%s: unable to reset hardware; hal status %u\n",
                        __func__, status);
        sc->sc_diversity = ath_hal_getdiversity(ah);
        if (ath_startrecv(sc) != 0)     /* restart recv */
                if_printf(ifp, "%s: unable to start recv logic\n", __func__);
        /*
         * We may be doing a reset in response to an ioctl
         * that changes the channel so update any state that
         * might change as a result.
         */
        ath_chan_change(sc, ic->ic_curchan);
        if (sc->sc_beacons) {           /* restart beacons */
#ifdef IEEE80211_SUPPORT_TDMA
                if (sc->sc_tdma)
                        ath_tdma_config(sc, NULL);
                else
#endif
                        ath_beacon_config(sc, NULL);
        }
        ath_hal_intrset(ah, sc->sc_imask);

        ath_start(ifp);                 /* restart xmit */
        return 0;
}

static int
ath_reset_vap(struct ieee80211vap *vap, u_long cmd)
{
        struct ieee80211com *ic = vap->iv_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;

        switch (cmd) {
        case IEEE80211_IOC_TXPOWER:
                /*
                 * If per-packet TPC is enabled, then we have nothing
                 * to do; otherwise we need to force the global limit.
                 * All this can happen directly; no need to reset.
                 */
                if (!ath_hal_gettpc(ah))
                        ath_hal_settxpowlimit(ah, ic->ic_txpowlimit);
                return 0;
        }
        return ath_reset(ifp);
}

static struct ath_buf *
_ath_getbuf_locked(struct ath_softc *sc)
{
        struct ath_buf *bf;

        bf = STAILQ_FIRST(&sc->sc_txbuf);
        if (bf != NULL && (bf->bf_flags & ATH_BUF_BUSY) == 0)
                STAILQ_REMOVE_HEAD(&sc->sc_txbuf, bf_list);
        else
                bf = NULL;
        if (bf == NULL) {
                kprintf("ath: ran out of descriptors\n");
                DPRINTF(sc, ATH_DEBUG_XMIT, "%s: %s\n", __func__,
                    STAILQ_FIRST(&sc->sc_txbuf) == NULL ?
                        "out of xmit buffers" : "xmit buffer busy");
        }
        return bf;
}

static struct ath_buf *
ath_getbuf(struct ath_softc *sc)
{
        struct ath_buf *bf;

        bf = _ath_getbuf_locked(sc);
        if (bf == NULL) {
                struct ifnet *ifp = sc->sc_ifp;

                DPRINTF(sc, ATH_DEBUG_XMIT, "%s: stop queue\n", __func__);
                sc->sc_stats.ast_tx_qstop++;
                ifp->if_flags |= IFF_OACTIVE;
        }
        return bf;
}

/*
 * Cleanup driver resources when we run out of buffers
 * while processing fragments; return the tx buffers
 * allocated and drop node references.
 */
static void
ath_txfrag_cleanup(struct ath_softc *sc,
        ath_bufhead *frags, struct ieee80211_node *ni)
{
        struct ath_buf *bf, *next;

        STAILQ_FOREACH_MUTABLE(bf, frags, bf_list, next) {
                /* NB: bf assumed clean */
                STAILQ_REMOVE_HEAD(frags, bf_list);
                STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
                ieee80211_node_decref(ni);
        }
}

/*
 * Setup xmit of a fragmented frame.  Allocate a buffer
 * for each frag and bump the node reference count to
 * reflect the held reference to be setup by ath_tx_start.
 */
static int
ath_txfrag_setup(struct ath_softc *sc, ath_bufhead *frags,
        struct mbuf *m0, struct ieee80211_node *ni)
{
        struct mbuf *m;
        struct ath_buf *bf;

        for (m = m0->m_nextpkt; m != NULL; m = m->m_nextpkt) {
                bf = _ath_getbuf_locked(sc);
                if (bf == NULL) {       /* out of buffers, cleanup */
                        ath_txfrag_cleanup(sc, frags, ni);
                        break;
                }
                ieee80211_node_incref(ni);
                STAILQ_INSERT_TAIL(frags, bf, bf_list);
        }

        return !STAILQ_EMPTY(frags);
}

static void
ath_start(struct ifnet *ifp)
{
        struct ath_softc *sc = ifp->if_softc;
        struct ieee80211_node *ni;
        struct ath_buf *bf;
        struct mbuf *m, *next;
        ath_bufhead frags;

        if ((ifp->if_flags & IFF_RUNNING) == 0 || sc->sc_invalid) {
                ifq_purge(&ifp->if_snd);
                return;
        }
        for (;;) {
                /*
                 * Grab a TX buffer and associated resources.
                 */
                bf = ath_getbuf(sc);
                if (bf == NULL)
                        break;

                IF_DEQUEUE(&ifp->if_snd, m);
                if (m == NULL) {
                        STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
                        break;
                }
                ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
                /*
                 * Check for fragmentation.  If this frame
                 * has been broken up verify we have enough
                 * buffers to send all the fragments so all
                 * go out or none...
                 */
                STAILQ_INIT(&frags);
                if ((m->m_flags & M_FRAG) && 
                    !ath_txfrag_setup(sc, &frags, m, ni)) {
                        DPRINTF(sc, ATH_DEBUG_XMIT,
                            "%s: out of txfrag buffers\n", __func__);
                        sc->sc_stats.ast_tx_nofrag++;
                        ifp->if_oerrors++;
                        ath_freetx(m);
                        goto bad;
                }
                ifp->if_opackets++;
        nextfrag:
                /*
                 * Pass the frame to the h/w for transmission.
                 * Fragmented frames have each frag chained together
                 * with m_nextpkt.  We know there are sufficient ath_buf's
                 * to send all the frags because of work done by
                 * ath_txfrag_setup.  We leave m_nextpkt set while
                 * calling ath_tx_start so it can use it to extend the
                 * the tx duration to cover the subsequent frag and
                 * so it can reclaim all the mbufs in case of an error;
                 * ath_tx_start clears m_nextpkt once it commits to
                 * handing the frame to the hardware.
                 */
                next = m->m_nextpkt;
                if (ath_tx_start(sc, ni, bf, m)) {
        bad:
                        ifp->if_oerrors++;
        reclaim:
                        bf->bf_m = NULL;
                        bf->bf_node = NULL;
                        STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
                        ath_txfrag_cleanup(sc, &frags, ni);
                        if (ni != NULL)
                                ieee80211_free_node(ni);
                        continue;
                }
                if (next != NULL) {
                        /*
                         * Beware of state changing between frags.
                         * XXX check sta power-save state?
                         */
                        if (ni->ni_vap->iv_state != IEEE80211_S_RUN) {
                                DPRINTF(sc, ATH_DEBUG_XMIT,
                                    "%s: flush fragmented packet, state %s\n",
                                    __func__,
                                    ieee80211_state_name[ni->ni_vap->iv_state]);
                                ath_freetx(next);
                                goto reclaim;
                        }
                        m = next;
                        bf = STAILQ_FIRST(&frags);
                        KASSERT(bf != NULL, ("no buf for txfrag"));
                        STAILQ_REMOVE_HEAD(&frags, bf_list);
                        goto nextfrag;
                }

                sc->sc_wd_timer = 5;
        }
}

static int
ath_media_change(struct ifnet *ifp)
{
        int error = ieee80211_media_change(ifp);
        /* NB: only the fixed rate can change and that doesn't need a reset */
        return (error == ENETRESET ? 0 : error);
}

#ifdef ATH_DEBUG
static void
ath_keyprint(struct ath_softc *sc, const char *tag, u_int ix,
        const HAL_KEYVAL *hk, const u_int8_t mac[IEEE80211_ADDR_LEN])
{
        static const char *ciphers[] = {
                "WEP",
                "AES-OCB",
                "AES-CCM",
                "CKIP",
                "TKIP",
                "CLR",
        };
        int i, n;

        kprintf("%s: [%02u] %-7s ", tag, ix, ciphers[hk->kv_type]);
        for (i = 0, n = hk->kv_len; i < n; i++)
                kprintf("%02x", hk->kv_val[i]);
        kprintf(" mac %6D", mac, ":");
        if (hk->kv_type == HAL_CIPHER_TKIP) {
                kprintf(" %s ", sc->sc_splitmic ? "mic" : "rxmic");
                for (i = 0; i < sizeof(hk->kv_mic); i++)
                        kprintf("%02x", hk->kv_mic[i]);
                if (!sc->sc_splitmic) {
                        kprintf(" txmic ");
                        for (i = 0; i < sizeof(hk->kv_txmic); i++)
                                kprintf("%02x", hk->kv_txmic[i]);
                }
        }
        kprintf("\n");
}
#endif

/*
 * Set a TKIP key into the hardware.  This handles the
 * potential distribution of key state to multiple key
 * cache slots for TKIP.
 */
static int
ath_keyset_tkip(struct ath_softc *sc, const struct ieee80211_key *k,
        HAL_KEYVAL *hk, const u_int8_t mac[IEEE80211_ADDR_LEN])
{
#define IEEE80211_KEY_XR        (IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV)
        static const u_int8_t zerobssid[IEEE80211_ADDR_LEN];
        struct ath_hal *ah = sc->sc_ah;

        KASSERT(k->wk_cipher->ic_cipher == IEEE80211_CIPHER_TKIP,
                ("got a non-TKIP key, cipher %u", k->wk_cipher->ic_cipher));
        if ((k->wk_flags & IEEE80211_KEY_XR) == IEEE80211_KEY_XR) {
                if (sc->sc_splitmic) {
                        /*
                         * TX key goes at first index, RX key at the rx index.
                         * The hal handles the MIC keys at index+64.
                         */
                        memcpy(hk->kv_mic, k->wk_txmic, sizeof(hk->kv_mic));
                        KEYPRINTF(sc, k->wk_keyix, hk, zerobssid);
                        if (!ath_hal_keyset(ah, k->wk_keyix, hk, zerobssid))
                                return 0;

                        memcpy(hk->kv_mic, k->wk_rxmic, sizeof(hk->kv_mic));
                        KEYPRINTF(sc, k->wk_keyix+32, hk, mac);
                        /* XXX delete tx key on failure? */
                        return ath_hal_keyset(ah, k->wk_keyix+32, hk, mac);
                } else {
                        /*
                         * Room for both TX+RX MIC keys in one key cache
                         * slot, just set key at the first index; the hal
                         * will handle the rest.
                         */
                        memcpy(hk->kv_mic, k->wk_rxmic, sizeof(hk->kv_mic));
                        memcpy(hk->kv_txmic, k->wk_txmic, sizeof(hk->kv_txmic));
                        KEYPRINTF(sc, k->wk_keyix, hk, mac);
                        return ath_hal_keyset(ah, k->wk_keyix, hk, mac);
                }
        } else if (k->wk_flags & IEEE80211_KEY_XMIT) {
                if (sc->sc_splitmic) {
                        /*
                         * NB: must pass MIC key in expected location when
                         * the keycache only holds one MIC key per entry.
                         */
                        memcpy(hk->kv_mic, k->wk_txmic, sizeof(hk->kv_txmic));
                } else
                        memcpy(hk->kv_txmic, k->wk_txmic, sizeof(hk->kv_txmic));
                KEYPRINTF(sc, k->wk_keyix, hk, mac);
                return ath_hal_keyset(ah, k->wk_keyix, hk, mac);
        } else if (k->wk_flags & IEEE80211_KEY_RECV) {
                memcpy(hk->kv_mic, k->wk_rxmic, sizeof(hk->kv_mic));
                KEYPRINTF(sc, k->wk_keyix, hk, mac);
                return ath_hal_keyset(ah, k->wk_keyix, hk, mac);
        }
        return 0;
#undef IEEE80211_KEY_XR
}

/*
 * Set a net80211 key into the hardware.  This handles the
 * potential distribution of key state to multiple key
 * cache slots for TKIP with hardware MIC support.
 */
static int
ath_keyset(struct ath_softc *sc, const struct ieee80211_key *k,
        struct ieee80211_node *bss)
{
        static const u_int8_t ciphermap[] = {
                HAL_CIPHER_WEP,         /* IEEE80211_CIPHER_WEP */
                HAL_CIPHER_TKIP,        /* IEEE80211_CIPHER_TKIP */
                HAL_CIPHER_AES_OCB,     /* IEEE80211_CIPHER_AES_OCB */
                HAL_CIPHER_AES_CCM,     /* IEEE80211_CIPHER_AES_CCM */
                (u_int8_t) -1,          /* 4 is not allocated */
                HAL_CIPHER_CKIP,        /* IEEE80211_CIPHER_CKIP */
                HAL_CIPHER_CLR,         /* IEEE80211_CIPHER_NONE */
        };
        struct ath_hal *ah = sc->sc_ah;
        const struct ieee80211_cipher *cip = k->wk_cipher;
        u_int8_t gmac[IEEE80211_ADDR_LEN];
        const u_int8_t *mac;
        HAL_KEYVAL hk;

        memset(&hk, 0, sizeof(hk));
        /*
         * Software crypto uses a "clear key" so non-crypto
         * state kept in the key cache are maintained and
         * so that rx frames have an entry to match.
         */
        if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) == 0) {
                KASSERT(cip->ic_cipher < NELEM(ciphermap),
                        ("invalid cipher type %u", cip->ic_cipher));
                hk.kv_type = ciphermap[cip->ic_cipher];
                hk.kv_len = k->wk_keylen;
                memcpy(hk.kv_val, k->wk_key, k->wk_keylen);
        } else
                hk.kv_type = HAL_CIPHER_CLR;

        if ((k->wk_flags & IEEE80211_KEY_GROUP) && sc->sc_mcastkey) {
                /*
                 * Group keys on hardware that supports multicast frame
                 * key search use a MAC that is the sender's address with
                 * the high bit set instead of the app-specified address.
                 */
                IEEE80211_ADDR_COPY(gmac, bss->ni_macaddr);
                gmac[0] |= 0x80;
                mac = gmac;
        } else
                mac = k->wk_macaddr;

        if (hk.kv_type == HAL_CIPHER_TKIP &&
            (k->wk_flags & IEEE80211_KEY_SWMIC) == 0) {
                return ath_keyset_tkip(sc, k, &hk, mac);
        } else {
                KEYPRINTF(sc, k->wk_keyix, &hk, mac);
                return ath_hal_keyset(ah, k->wk_keyix, &hk, mac);
        }
}

/*
 * Allocate tx/rx key slots for TKIP.  We allocate two slots for
 * each key, one for decrypt/encrypt and the other for the MIC.
 */
static u_int16_t
key_alloc_2pair(struct ath_softc *sc,
        ieee80211_keyix *txkeyix, ieee80211_keyix *rxkeyix)
{
        u_int i, keyix;

        KASSERT(sc->sc_splitmic, ("key cache !split"));
        /* XXX could optimize */
        for (i = 0; i < NELEM(sc->sc_keymap)/4; i++) {
                u_int8_t b = sc->sc_keymap[i];
                if (b != 0xff) {
                        /*
                         * One or more slots in this byte are free.
                         */
                        keyix = i*NBBY;
                        while (b & 1) {
                again:
                                keyix++;
                                b >>= 1;
                        }
                        /* XXX IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV */
                        if (isset(sc->sc_keymap, keyix+32) ||
                            isset(sc->sc_keymap, keyix+64) ||
                            isset(sc->sc_keymap, keyix+32+64)) {
                                /* full pair unavailable */
                                /* XXX statistic */
                                if (keyix == (i+1)*NBBY) {
                                        /* no slots were appropriate, advance */
                                        continue;
                                }
                                goto again;
                        }
                        setbit(sc->sc_keymap, keyix);
                        setbit(sc->sc_keymap, keyix+64);
                        setbit(sc->sc_keymap, keyix+32);
                        setbit(sc->sc_keymap, keyix+32+64);
                        DPRINTF(sc, ATH_DEBUG_KEYCACHE,
                                "%s: key pair %u,%u %u,%u\n",
                                __func__, keyix, keyix+64,
                                keyix+32, keyix+32+64);
                        *txkeyix = keyix;
                        *rxkeyix = keyix+32;
                        return 1;
                }
        }
        DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: out of pair space\n", __func__);
        return 0;
}

/*
 * Allocate tx/rx key slots for TKIP.  We allocate two slots for
 * each key, one for decrypt/encrypt and the other for the MIC.
 */
static u_int16_t
key_alloc_pair(struct ath_softc *sc,
        ieee80211_keyix *txkeyix, ieee80211_keyix *rxkeyix)
{
        u_int i, keyix;

        KASSERT(!sc->sc_splitmic, ("key cache split"));
        /* XXX could optimize */
        for (i = 0; i < NELEM(sc->sc_keymap)/4; i++) {
                u_int8_t b = sc->sc_keymap[i];
                if (b != 0xff) {
                        /*
                         * One or more slots in this byte are free.
                         */
                        keyix = i*NBBY;
                        while (b & 1) {
                again:
                                keyix++;
                                b >>= 1;
                        }
                        if (isset(sc->sc_keymap, keyix+64)) {
                                /* full pair unavailable */
                                /* XXX statistic */
                                if (keyix == (i+1)*NBBY) {
                                        /* no slots were appropriate, advance */
                                        continue;
                                }
                                goto again;
                        }
                        setbit(sc->sc_keymap, keyix);
                        setbit(sc->sc_keymap, keyix+64);
                        DPRINTF(sc, ATH_DEBUG_KEYCACHE,
                                "%s: key pair %u,%u\n",
                                __func__, keyix, keyix+64);
                        *txkeyix = *rxkeyix = keyix;
                        return 1;
                }
        }
        DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: out of pair space\n", __func__);
        return 0;
}

/*
 * Allocate a single key cache slot.
 */
static int
key_alloc_single(struct ath_softc *sc,
        ieee80211_keyix *txkeyix, ieee80211_keyix *rxkeyix)
{
        u_int i, keyix;

        /* XXX try i,i+32,i+64,i+32+64 to minimize key pair conflicts */
        for (i = 0; i < NELEM(sc->sc_keymap); i++) {
                u_int8_t b = sc->sc_keymap[i];
                if (b != 0xff) {
                        /*
                         * One or more slots are free.
                         */
                        keyix = i*NBBY;
                        while (b & 1)
                                keyix++, b >>= 1;
                        setbit(sc->sc_keymap, keyix);
                        DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: key %u\n",
                                __func__, keyix);
                        *txkeyix = *rxkeyix = keyix;
                        return 1;
                }
        }
        DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: out of space\n", __func__);
        return 0;
}

/*
 * Allocate one or more key cache slots for a uniacst key.  The
 * key itself is needed only to identify the cipher.  For hardware
 * TKIP with split cipher+MIC keys we allocate two key cache slot
 * pairs so that we can setup separate TX and RX MIC keys.  Note
 * that the MIC key for a TKIP key at slot i is assumed by the
 * hardware to be at slot i+64.  This limits TKIP keys to the first
 * 64 entries.
 */
static int
ath_key_alloc(struct ieee80211vap *vap, struct ieee80211_key *k,
        ieee80211_keyix *keyix, ieee80211_keyix *rxkeyix)
{
        struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;

        /*
         * Group key allocation must be handled specially for
         * parts that do not support multicast key cache search
         * functionality.  For those parts the key id must match
         * the h/w key index so lookups find the right key.  On
         * parts w/ the key search facility we install the sender's
         * mac address (with the high bit set) and let the hardware
         * find the key w/o using the key id.  This is preferred as
         * it permits us to support multiple users for adhoc and/or
         * multi-station operation.
         */
        if (k->wk_keyix != IEEE80211_KEYIX_NONE) {
                /*
                 * Only global keys should have key index assigned.
                 */
                if (!(&vap->iv_nw_keys[0] <= k &&
                      k < &vap->iv_nw_keys[IEEE80211_WEP_NKID])) {
                        /* should not happen */
                        DPRINTF(sc, ATH_DEBUG_KEYCACHE,
                                "%s: bogus group key\n", __func__);
                        return 0;
                }
                if (vap->iv_opmode != IEEE80211_M_HOSTAP ||
                    !(k->wk_flags & IEEE80211_KEY_GROUP) ||
                    !sc->sc_mcastkey) {
                        /*
                         * XXX we pre-allocate the global keys so
                         * have no way to check if they've already
                         * been allocated.
                         */
                        *keyix = *rxkeyix = k - vap->iv_nw_keys;
                        return 1;
                }
                /*
                 * Group key and device supports multicast key search.
                 */
                k->wk_keyix = IEEE80211_KEYIX_NONE;
        }

        /*
         * We allocate two pair for TKIP when using the h/w to do
         * the MIC.  For everything else, including software crypto,
         * we allocate a single entry.  Note that s/w crypto requires
         * a pass-through slot on the 5211 and 5212.  The 5210 does
         * not support pass-through cache entries and we map all
         * those requests to slot 0.
         */
        if (k->wk_flags & IEEE80211_KEY_SWCRYPT) {
                return key_alloc_single(sc, keyix, rxkeyix);
        } else if (k->wk_cipher->ic_cipher == IEEE80211_CIPHER_TKIP &&
            (k->wk_flags & IEEE80211_KEY_SWMIC) == 0) {
                if (sc->sc_splitmic)
                        return key_alloc_2pair(sc, keyix, rxkeyix);
                else
                        return key_alloc_pair(sc, keyix, rxkeyix);
        } else {
                return key_alloc_single(sc, keyix, rxkeyix);
        }
}

/*
 * Delete an entry in the key cache allocated by ath_key_alloc.
 */
static int
ath_key_delete(struct ieee80211vap *vap, const struct ieee80211_key *k)
{
        struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;
        const struct ieee80211_cipher *cip = k->wk_cipher;
        u_int keyix = k->wk_keyix;

        DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: delete key %u\n", __func__, keyix);

        ath_hal_keyreset(ah, keyix);
        /*
         * Handle split tx/rx keying required for TKIP with h/w MIC.
         */
        if (cip->ic_cipher == IEEE80211_CIPHER_TKIP &&
            (k->wk_flags & IEEE80211_KEY_SWMIC) == 0 && sc->sc_splitmic)
                ath_hal_keyreset(ah, keyix+32);         /* RX key */
        if (keyix >= IEEE80211_WEP_NKID) {
                /*
                 * Don't touch keymap entries for global keys so
                 * they are never considered for dynamic allocation.
                 */
                clrbit(sc->sc_keymap, keyix);
                if (cip->ic_cipher == IEEE80211_CIPHER_TKIP &&
                    (k->wk_flags & IEEE80211_KEY_SWMIC) == 0) {
                        clrbit(sc->sc_keymap, keyix+64);        /* TX key MIC */
                        if (sc->sc_splitmic) {
                                /* +32 for RX key, +32+64 for RX key MIC */
                                clrbit(sc->sc_keymap, keyix+32);
                                clrbit(sc->sc_keymap, keyix+32+64);
                        }
                }
        }
        return 1;
}

/*
 * Set the key cache contents for the specified key.  Key cache
 * slot(s) must already have been allocated by ath_key_alloc.
 */
static int
ath_key_set(struct ieee80211vap *vap, const struct ieee80211_key *k,
        const u_int8_t mac[IEEE80211_ADDR_LEN])
{
        struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;

        return ath_keyset(sc, k, vap->iv_bss);
}

/*
 * Block/unblock tx+rx processing while a key change is done.
 * We assume the caller serializes key management operations
 * so we only need to worry about synchronization with other
 * uses that originate in the driver.
 */
static void
ath_key_update_begin(struct ieee80211vap *vap)
{
        struct ifnet *ifp = vap->iv_ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;

        DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s:\n", __func__);
        taskqueue_block(sc->sc_tq);
}

static void
ath_key_update_end(struct ieee80211vap *vap)
{
        struct ifnet *ifp = vap->iv_ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;

        DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s:\n", __func__);
        taskqueue_unblock(sc->sc_tq);
}

/*
 * Calculate the receive filter according to the
 * operating mode and state:
 *
 * o always accept unicast, broadcast, and multicast traffic
 * o accept PHY error frames when hardware doesn't have MIB support
 *   to count and we need them for ANI (sta mode only until recently)
 *   and we are not scanning (ANI is disabled)
 *   NB: older hal's add rx filter bits out of sight and we need to
 *       blindly preserve them
 * o probe request frames are accepted only when operating in
 *   hostap, adhoc, mesh, or monitor modes
 * o enable promiscuous mode
 *   - when in monitor mode
 *   - if interface marked PROMISC (assumes bridge setting is filtered)
 * o accept beacons:
 *   - when operating in station mode for collecting rssi data when
 *     the station is otherwise quiet, or
 *   - when operating in adhoc mode so the 802.11 layer creates
 *     node table entries for peers,
 *   - when scanning
 *   - when doing s/w beacon miss (e.g. for ap+sta)
 *   - when operating in ap mode in 11g to detect overlapping bss that
 *     require protection
 *   - when operating in mesh mode to detect neighbors
 * o accept control frames:
 *   - when in monitor mode
 * XXX BAR frames for 11n
 * XXX HT protection for 11n
 */
static u_int32_t
ath_calcrxfilter(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        u_int32_t rfilt;

        rfilt = HAL_RX_FILTER_UCAST | HAL_RX_FILTER_BCAST | HAL_RX_FILTER_MCAST;
        if (!sc->sc_needmib && !sc->sc_scanning)
                rfilt |= HAL_RX_FILTER_PHYERR;
        if (ic->ic_opmode != IEEE80211_M_STA)
                rfilt |= HAL_RX_FILTER_PROBEREQ;
        /* XXX ic->ic_monvaps != 0? */
        if (ic->ic_opmode == IEEE80211_M_MONITOR || (ifp->if_flags & IFF_PROMISC))
                rfilt |= HAL_RX_FILTER_PROM;
        if (ic->ic_opmode == IEEE80211_M_STA ||
            ic->ic_opmode == IEEE80211_M_IBSS ||
            sc->sc_swbmiss || sc->sc_scanning)
                rfilt |= HAL_RX_FILTER_BEACON;
        /*
         * NB: We don't recalculate the rx filter when
         * ic_protmode changes; otherwise we could do
         * this only when ic_protmode != NONE.
         */
        if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
            IEEE80211_IS_CHAN_ANYG(ic->ic_curchan))
                rfilt |= HAL_RX_FILTER_BEACON;
        if (sc->sc_nmeshvaps) {
                rfilt |= HAL_RX_FILTER_BEACON;
                if (sc->sc_hasbmatch)
                        rfilt |= HAL_RX_FILTER_BSSID;
                else
                        rfilt |= HAL_RX_FILTER_PROM;
        }
        if (ic->ic_opmode == IEEE80211_M_MONITOR)
                rfilt |= HAL_RX_FILTER_CONTROL;
        DPRINTF(sc, ATH_DEBUG_MODE, "%s: RX filter 0x%x, %s if_flags 0x%x\n",
            __func__, rfilt, ieee80211_opmode_name[ic->ic_opmode], ifp->if_flags);
        return rfilt;
}

static void
ath_update_promisc(struct ifnet *ifp)
{
        struct ath_softc *sc = ifp->if_softc;
        u_int32_t rfilt;

        /* configure rx filter */
        rfilt = ath_calcrxfilter(sc);
        ath_hal_setrxfilter(sc->sc_ah, rfilt);

        DPRINTF(sc, ATH_DEBUG_MODE, "%s: RX filter 0x%x\n", __func__, rfilt);
}

static void
ath_update_mcast(struct ifnet *ifp)
{
        struct ath_softc *sc = ifp->if_softc;
        u_int32_t mfilt[2];

        /* calculate and install multicast filter */
        if ((ifp->if_flags & IFF_ALLMULTI) == 0) {
                struct ifmultiaddr *ifma;
                /*
                 * Merge multicast addresses to form the hardware filter.
                 */
                mfilt[0] = mfilt[1] = 0;
#ifdef __FreeBSD__
                if_maddr_rlock(ifp);    /* XXX need some fiddling to remove? */
#endif
                TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
                        caddr_t dl;
                        u_int32_t val;
                        u_int8_t pos;

                        /* calculate XOR of eight 6bit values */
                        dl = LLADDR((struct sockaddr_dl *) ifma->ifma_addr);
                        val = LE_READ_4(dl + 0);
                        pos = (val >> 18) ^ (val >> 12) ^ (val >> 6) ^ val;
                        val = LE_READ_4(dl + 3);
                        pos ^= (val >> 18) ^ (val >> 12) ^ (val >> 6) ^ val;
                        pos &= 0x3f;
                        mfilt[pos / 32] |= (1 << (pos % 32));
                }
#ifdef __FreeBSD__
                if_maddr_runlock(ifp);
#endif
        } else
                mfilt[0] = mfilt[1] = ~0;
        ath_hal_setmcastfilter(sc->sc_ah, mfilt[0], mfilt[1]);
        DPRINTF(sc, ATH_DEBUG_MODE, "%s: MC filter %08x:%08x\n",
                __func__, mfilt[0], mfilt[1]);
}

static void
ath_mode_init(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ath_hal *ah = sc->sc_ah;
        u_int32_t rfilt;

        /* configure rx filter */
        rfilt = ath_calcrxfilter(sc);
        ath_hal_setrxfilter(ah, rfilt);

        /* configure operational mode */
        ath_hal_setopmode(ah);

        /* handle any link-level address change */
        ath_hal_setmac(ah, IF_LLADDR(ifp));

        /* calculate and install multicast filter */
        ath_update_mcast(ifp);
}

/*
 * Set the slot time based on the current setting.
 */
static void
ath_setslottime(struct ath_softc *sc)
{
        struct ieee80211com *ic = sc->sc_ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        u_int usec;

        if (IEEE80211_IS_CHAN_HALF(ic->ic_curchan))
                usec = 13;
        else if (IEEE80211_IS_CHAN_QUARTER(ic->ic_curchan))
                usec = 21;
        else if (IEEE80211_IS_CHAN_ANYG(ic->ic_curchan)) {
                /* honor short/long slot time only in 11g */
                /* XXX shouldn't honor on pure g or turbo g channel */
                if (ic->ic_flags & IEEE80211_F_SHSLOT)
                        usec = HAL_SLOT_TIME_9;
                else
                        usec = HAL_SLOT_TIME_20;
        } else
                usec = HAL_SLOT_TIME_9;

        DPRINTF(sc, ATH_DEBUG_RESET,
            "%s: chan %u MHz flags 0x%x %s slot, %u usec\n",
            __func__, ic->ic_curchan->ic_freq, ic->ic_curchan->ic_flags,
            ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long", usec);

        ath_hal_setslottime(ah, usec);
        sc->sc_updateslot = OK;
}

/*
 * Callback from the 802.11 layer to update the
 * slot time based on the current setting.
 */
static void
ath_updateslot(struct ifnet *ifp)
{
        struct ath_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = ifp->if_l2com;

        /*
         * When not coordinating the BSS, change the hardware
         * immediately.  For other operation we defer the change
         * until beacon updates have propagated to the stations.
         */
        if (ic->ic_opmode == IEEE80211_M_HOSTAP ||
            ic->ic_opmode == IEEE80211_M_MBSS)
                sc->sc_updateslot = UPDATE;
        else
                ath_setslottime(sc);
}

/*
 * Setup a h/w transmit queue for beacons.
 */
static int
ath_beaconq_setup(struct ath_hal *ah)
{
        HAL_TXQ_INFO qi;

        memset(&qi, 0, sizeof(qi));
        qi.tqi_aifs = HAL_TXQ_USEDEFAULT;
        qi.tqi_cwmin = HAL_TXQ_USEDEFAULT;
        qi.tqi_cwmax = HAL_TXQ_USEDEFAULT;
        /* NB: for dynamic turbo, don't enable any other interrupts */
        qi.tqi_qflags = HAL_TXQ_TXDESCINT_ENABLE;
        return ath_hal_setuptxqueue(ah, HAL_TX_QUEUE_BEACON, &qi);
}

/*
 * Setup the transmit queue parameters for the beacon queue.
 */
static int
ath_beaconq_config(struct ath_softc *sc)
{
#define ATH_EXPONENT_TO_VALUE(v)        ((1<<(v))-1)
        struct ieee80211com *ic = sc->sc_ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        HAL_TXQ_INFO qi;

        ath_hal_gettxqueueprops(ah, sc->sc_bhalq, &qi);
        if (ic->ic_opmode == IEEE80211_M_HOSTAP ||
            ic->ic_opmode == IEEE80211_M_MBSS) {
                /*
                 * Always burst out beacon and CAB traffic.
                 */
                qi.tqi_aifs = ATH_BEACON_AIFS_DEFAULT;
                qi.tqi_cwmin = ATH_BEACON_CWMIN_DEFAULT;
                qi.tqi_cwmax = ATH_BEACON_CWMAX_DEFAULT;
        } else {
                struct wmeParams *wmep =
                        &ic->ic_wme.wme_chanParams.cap_wmeParams[WME_AC_BE];
                /*
                 * Adhoc mode; important thing is to use 2x cwmin.
                 */
                qi.tqi_aifs = wmep->wmep_aifsn;
                qi.tqi_cwmin = 2*ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmin);
                qi.tqi_cwmax = ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmax);
        }

        if (!ath_hal_settxqueueprops(ah, sc->sc_bhalq, &qi)) {
                device_printf(sc->sc_dev, "unable to update parameters for "
                        "beacon hardware queue!\n");
                return 0;
        } else {
                ath_hal_resettxqueue(ah, sc->sc_bhalq); /* push to h/w */
                return 1;
        }
#undef ATH_EXPONENT_TO_VALUE
}

/*
 * Allocate and setup an initial beacon frame.
 */
static int
ath_beacon_alloc(struct ath_softc *sc, struct ieee80211_node *ni)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct ath_vap *avp = ATH_VAP(vap);
        struct ath_buf *bf;
        struct mbuf *m;
        int error;

        bf = avp->av_bcbuf;
        if (bf->bf_m != NULL) {
                bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
                m_freem(bf->bf_m);
                bf->bf_m = NULL;
        }
        if (bf->bf_node != NULL) {
                ieee80211_free_node(bf->bf_node);
                bf->bf_node = NULL;
        }

        /*
         * NB: the beacon data buffer must be 32-bit aligned;
         * we assume the mbuf routines will return us something
         * with this alignment (perhaps should assert).
         */
        m = ieee80211_beacon_alloc(ni, &avp->av_boff);
        if (m == NULL) {
                device_printf(sc->sc_dev, "%s: cannot get mbuf\n", __func__);
                sc->sc_stats.ast_be_nombuf++;
                return ENOMEM;
        }
        error = bus_dmamap_load_mbuf_segment(sc->sc_dmat, bf->bf_dmamap, m,
                                     bf->bf_segs, 1, &bf->bf_nseg,
                                     BUS_DMA_NOWAIT);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: cannot map mbuf, bus_dmamap_load_mbuf_segment returns %d\n",
                    __func__, error);
                m_freem(m);
                return error;
        }

        /*
         * Calculate a TSF adjustment factor required for staggered
         * beacons.  Note that we assume the format of the beacon
         * frame leaves the tstamp field immediately following the
         * header.
         */
        if (sc->sc_stagbeacons && avp->av_bslot > 0) {
                uint64_t tsfadjust;
                struct ieee80211_frame *wh;

                /*
                 * The beacon interval is in TU's; the TSF is in usecs.
                 * We figure out how many TU's to add to align the timestamp
                 * then convert to TSF units and handle byte swapping before
                 * inserting it in the frame.  The hardware will then add this
                 * each time a beacon frame is sent.  Note that we align vap's
                 * 1..N and leave vap 0 untouched.  This means vap 0 has a
                 * timestamp in one beacon interval while the others get a
                 * timstamp aligned to the next interval.
                 */
                tsfadjust = ni->ni_intval *
                    (ATH_BCBUF - avp->av_bslot) / ATH_BCBUF;
                tsfadjust = htole64(tsfadjust << 10);   /* TU -> TSF */

                DPRINTF(sc, ATH_DEBUG_BEACON,
                    "%s: %s beacons bslot %d intval %u tsfadjust %llu\n",
                    __func__, sc->sc_stagbeacons ? "stagger" : "burst",
                    avp->av_bslot, ni->ni_intval,
                    (long long unsigned) le64toh(tsfadjust));

                wh = mtod(m, struct ieee80211_frame *);
                memcpy(&wh[1], &tsfadjust, sizeof(tsfadjust));
        }
        bf->bf_m = m;
        bf->bf_node = ieee80211_ref_node(ni);

        return 0;
}

/*
 * Setup the beacon frame for transmit.
 */
static void
ath_beacon_setup(struct ath_softc *sc, struct ath_buf *bf)
{
#define USE_SHPREAMBLE(_ic) \
        (((_ic)->ic_flags & (IEEE80211_F_SHPREAMBLE | IEEE80211_F_USEBARKER))\
                == IEEE80211_F_SHPREAMBLE)
        struct ieee80211_node *ni = bf->bf_node;
        struct ieee80211com *ic = ni->ni_ic;
        struct mbuf *m = bf->bf_m;
        struct ath_hal *ah = sc->sc_ah;
        struct ath_desc *ds;
        int flags, antenna;
        const HAL_RATE_TABLE *rt;
        u_int8_t rix, rate;

        DPRINTF(sc, ATH_DEBUG_BEACON_PROC, "%s: m %p len %u\n",
                __func__, m, m->m_len);

        /* setup descriptors */
        ds = bf->bf_desc;

        flags = HAL_TXDESC_NOACK;
        if (ic->ic_opmode == IEEE80211_M_IBSS && sc->sc_hasveol) {
                ds->ds_link = bf->bf_daddr;     /* self-linked */
                flags |= HAL_TXDESC_VEOL;
                /*
                 * Let hardware handle antenna switching.
                 */
                antenna = sc->sc_txantenna;
        } else {
                ds->ds_link = 0;
                /*
                 * Switch antenna every 4 beacons.
                 * XXX assumes two antenna
                 */
                if (sc->sc_txantenna != 0)
                        antenna = sc->sc_txantenna;
                else if (sc->sc_stagbeacons && sc->sc_nbcnvaps != 0)
                        antenna = ((sc->sc_stats.ast_be_xmit / sc->sc_nbcnvaps) & 4 ? 2 : 1);
                else
                        antenna = (sc->sc_stats.ast_be_xmit & 4 ? 2 : 1);
        }

        KASSERT(bf->bf_nseg == 1,
                ("multi-segment beacon frame; nseg %u", bf->bf_nseg));
        ds->ds_data = bf->bf_segs[0].ds_addr;
        /*
         * Calculate rate code.
         * XXX everything at min xmit rate
         */
        rix = 0;
        rt = sc->sc_currates;
        rate = rt->info[rix].rateCode;
        if (USE_SHPREAMBLE(ic))
                rate |= rt->info[rix].shortPreamble;
        ath_hal_setuptxdesc(ah, ds
                , m->m_len + IEEE80211_CRC_LEN  /* frame length */
                , sizeof(struct ieee80211_frame)/* header length */
                , HAL_PKT_TYPE_BEACON           /* Atheros packet type */
                , ni->ni_txpower                /* txpower XXX */
                , rate, 1                       /* series 0 rate/tries */
                , HAL_TXKEYIX_INVALID           /* no encryption */
                , antenna                       /* antenna mode */
                , flags                         /* no ack, veol for beacons */
                , 0                             /* rts/cts rate */
                , 0                             /* rts/cts duration */
        );
        /* NB: beacon's BufLen must be a multiple of 4 bytes */
        ath_hal_filltxdesc(ah, ds
                , roundup(m->m_len, 4)          /* buffer length */
                , AH_TRUE                       /* first segment */
                , AH_TRUE                       /* last segment */
                , ds                            /* first descriptor */
        );
#if 0
        ath_desc_swap(ds);
#endif
#undef USE_SHPREAMBLE
}

static void
ath_beacon_update(struct ieee80211vap *vap, int item)
{
        struct ieee80211_beacon_offsets *bo = &ATH_VAP(vap)->av_boff;

        setbit(bo->bo_flags, item);
}

/*
 * Append the contents of src to dst; both queues
 * are assumed to be locked.
 */
static void
ath_txqmove(struct ath_txq *dst, struct ath_txq *src)
{
        STAILQ_CONCAT(&dst->axq_q, &src->axq_q);
        if (src->axq_depth)
                dst->axq_link = src->axq_link;
        src->axq_link = NULL;
        dst->axq_depth += src->axq_depth;
        src->axq_depth = 0;
}

/*
 * Transmit a beacon frame at SWBA.  Dynamic updates to the
 * frame contents are done as needed and the slot time is
 * also adjusted based on current state.
 */
static void
ath_beacon_proc(void *arg, int pending)
{
        struct ath_softc *sc = arg;
        struct ath_hal *ah = sc->sc_ah;
        struct ieee80211vap *vap;
        struct ath_buf *bf;
        int slot, otherant;
        uint32_t bfaddr;

        DPRINTF(sc, ATH_DEBUG_BEACON_PROC, "%s: pending %u\n",
                __func__, pending);
        /*
         * Check if the previous beacon has gone out.  If
         * not don't try to post another, skip this period
         * and wait for the next.  Missed beacons indicate
         * a problem and should not occur.  If we miss too
         * many consecutive beacons reset the device.
         */
        if (ath_hal_numtxpending(ah, sc->sc_bhalq) != 0) {
                sc->sc_bmisscount++;
                DPRINTF(sc, ATH_DEBUG_BEACON,
                        "%s: missed %u consecutive beacons\n",
                        __func__, sc->sc_bmisscount);
                if (sc->sc_bmisscount >= ath_bstuck_threshold)
                        taskqueue_enqueue(sc->sc_tq, &sc->sc_bstucktask);
                return;
        }
        if (sc->sc_bmisscount != 0) {
                DPRINTF(sc, ATH_DEBUG_BEACON,
                        "%s: resume beacon xmit after %u misses\n",
                        __func__, sc->sc_bmisscount);
                sc->sc_bmisscount = 0;
        }

        /*
         * Stop any current dma before messing with the beacon linkages.
         */
        if (!ath_hal_stoptxdma(ah, sc->sc_bhalq)) {
                DPRINTF(sc, ATH_DEBUG_ANY,
                        "%s: beacon queue %u did not stop?\n",
                        __func__, sc->sc_bhalq);
        }

        if (sc->sc_stagbeacons) {                       /* staggered beacons */
                struct ieee80211com *ic = sc->sc_ifp->if_l2com;
                uint32_t tsftu;

                tsftu = ath_hal_gettsf32(ah) >> 10;
                /* XXX lintval */
                slot = ((tsftu % ic->ic_lintval) * ATH_BCBUF) / ic->ic_lintval;
                vap = sc->sc_bslot[(slot+1) % ATH_BCBUF];
                bfaddr = 0;
                if (vap != NULL && vap->iv_state >= IEEE80211_S_RUN) {
                        bf = ath_beacon_generate(sc, vap);
                        if (bf != NULL)
                                bfaddr = bf->bf_daddr;
                }
        } else {                                        /* burst'd beacons */
                uint32_t *bflink = &bfaddr;

                for (slot = 0; slot < ATH_BCBUF; slot++) {
                        vap = sc->sc_bslot[slot];
                        if (vap != NULL && vap->iv_state >= IEEE80211_S_RUN) {
                                bf = ath_beacon_generate(sc, vap);
                                if (bf != NULL) {
                                        *bflink = bf->bf_daddr;
                                        bflink = &bf->bf_desc->ds_link;
                                }
                        }
                }
                *bflink = 0;                            /* terminate list */
        }

        /*
         * Handle slot time change when a non-ERP station joins/leaves
         * an 11g network.  The 802.11 layer notifies us via callback,
         * we mark updateslot, then wait one beacon before effecting
         * the change.  This gives associated stations at least one
         * beacon interval to note the state change.
         */
        /* XXX locking */
        if (sc->sc_updateslot == UPDATE) {
                sc->sc_updateslot = COMMIT;     /* commit next beacon */
                sc->sc_slotupdate = slot;
        } else if (sc->sc_updateslot == COMMIT && sc->sc_slotupdate == slot)
                ath_setslottime(sc);            /* commit change to h/w */

        /*
         * Check recent per-antenna transmit statistics and flip
         * the default antenna if noticeably more frames went out
         * on the non-default antenna.
         * XXX assumes 2 anntenae
         */
        if (!sc->sc_diversity && (!sc->sc_stagbeacons || slot == 0)) {
                otherant = sc->sc_defant & 1 ? 2 : 1;
                if (sc->sc_ant_tx[otherant] > sc->sc_ant_tx[sc->sc_defant] + 2)
                        ath_setdefantenna(sc, otherant);
                sc->sc_ant_tx[1] = sc->sc_ant_tx[2] = 0;
        }

        if (bfaddr != 0) {
                /* NB: cabq traffic should already be queued and primed */
                ath_hal_puttxbuf(ah, sc->sc_bhalq, bfaddr);
                sc->sc_stats.ast_be_xmit++;
                ath_hal_txstart(ah, sc->sc_bhalq);
        }
        /* else no beacon will be generated */
}

static struct ath_buf *
ath_beacon_generate(struct ath_softc *sc, struct ieee80211vap *vap)
{
        struct ath_vap *avp = ATH_VAP(vap);
        struct ath_txq *cabq = sc->sc_cabq;
        struct ath_buf *bf;
        struct mbuf *m;
        int nmcastq, error;

        KASSERT(vap->iv_state >= IEEE80211_S_RUN,
            ("not running, state %d", vap->iv_state));
        KASSERT(avp->av_bcbuf != NULL, ("no beacon buffer"));

        /*
         * Update dynamic beacon contents.  If this returns
         * non-zero then we need to remap the memory because
         * the beacon frame changed size (probably because
         * of the TIM bitmap).
         */
        bf = avp->av_bcbuf;
        m = bf->bf_m;
        nmcastq = avp->av_mcastq.axq_depth;
        if (ieee80211_beacon_update(bf->bf_node, &avp->av_boff, m, nmcastq)) {
                /* XXX too conservative? */
                bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
                error = bus_dmamap_load_mbuf_segment(sc->sc_dmat, bf->bf_dmamap, m,
                                             bf->bf_segs, 1, &bf->bf_nseg,
                                             BUS_DMA_NOWAIT);
                if (error != 0) {
                        if_printf(vap->iv_ifp,
                            "%s: bus_dmamap_load_mbuf_segment failed, error %u\n",
                            __func__, error);
                        return NULL;
                }
        }
        if ((avp->av_boff.bo_tim[4] & 1) && cabq->axq_depth) {
                DPRINTF(sc, ATH_DEBUG_BEACON,
                    "%s: cabq did not drain, mcastq %u cabq %u\n",
                    __func__, nmcastq, cabq->axq_depth);
                sc->sc_stats.ast_cabq_busy++;
                if (sc->sc_nvaps > 1 && sc->sc_stagbeacons) {
                        /*
                         * CABQ traffic from a previous vap is still pending.
                         * We must drain the q before this beacon frame goes
                         * out as otherwise this vap's stations will get cab
                         * frames from a different vap.
                         * XXX could be slow causing us to miss DBA
                         */
                        ath_tx_draintxq(sc, cabq);
                }
        }
        ath_beacon_setup(sc, bf);
        bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);

        /*
         * Enable the CAB queue before the beacon queue to
         * insure cab frames are triggered by this beacon.
         */
        if (avp->av_boff.bo_tim[4] & 1) {
                struct ath_hal *ah = sc->sc_ah;

                /* NB: only at DTIM */
                if (nmcastq) {
                        struct ath_buf *bfm;
                        int qbusy;

                        /*
                         * Move frames from the s/w mcast q to the h/w cab q.
                         * XXX MORE_DATA bit
                         */
                        bfm = STAILQ_FIRST(&avp->av_mcastq.axq_q);
                        qbusy = ath_hal_txqenabled(ah, cabq->axq_qnum);
                        if (qbusy == 0) {
                                if (cabq->axq_link != NULL) {
                                        cpu_sfence();
                                        *cabq->axq_link = bfm->bf_daddr;
                                        cabq->axq_flags |= ATH_TXQ_PUTPENDING;
                                } else {
                                        cpu_sfence();
                                        ath_hal_puttxbuf(ah, cabq->axq_qnum,
                                                bfm->bf_daddr);
                                }
                        } else {
                                if (cabq->axq_link != NULL) {
                                        cpu_sfence();
                                        *cabq->axq_link = bfm->bf_daddr;
                                }
                                cabq->axq_flags |= ATH_TXQ_PUTPENDING;
                        }
                        ath_txqmove(cabq, &avp->av_mcastq);

                        sc->sc_stats.ast_cabq_xmit += nmcastq;
                }
                /* NB: gated by beacon so safe to start here */
                ath_hal_txstart(ah, cabq->axq_qnum);
        }
        return bf;
}

static void
ath_beacon_start_adhoc(struct ath_softc *sc, struct ieee80211vap *vap)
{
        struct ath_vap *avp = ATH_VAP(vap);
        struct ath_hal *ah = sc->sc_ah;
        struct ath_buf *bf;
        struct mbuf *m;
        int error;

        KASSERT(avp->av_bcbuf != NULL, ("no beacon buffer"));

        /*
         * Update dynamic beacon contents.  If this returns
         * non-zero then we need to remap the memory because
         * the beacon frame changed size (probably because
         * of the TIM bitmap).
         */
        bf = avp->av_bcbuf;
        m = bf->bf_m;
        if (ieee80211_beacon_update(bf->bf_node, &avp->av_boff, m, 0)) {
                /* XXX too conservative? */
                bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
                error = bus_dmamap_load_mbuf_segment(sc->sc_dmat, bf->bf_dmamap, m,
                                             bf->bf_segs, 1, &bf->bf_nseg,
                                             BUS_DMA_NOWAIT);
                if (error != 0) {
                        if_printf(vap->iv_ifp,
                            "%s: bus_dmamap_load_mbuf_segment failed, error %u\n",
                            __func__, error);
                        return;
                }
        }
        ath_beacon_setup(sc, bf);
        bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);

        /* NB: caller is known to have already stopped tx dma */
        ath_hal_puttxbuf(ah, sc->sc_bhalq, bf->bf_daddr);
        ath_hal_txstart(ah, sc->sc_bhalq);
}

/*
 * Reset the hardware after detecting beacons have stopped.
 */
static void
ath_bstuck_task(void *arg, int pending)
{
        struct ath_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ifp;

        wlan_serialize_enter();
        if_printf(ifp, "stuck beacon; resetting (bmiss count %u)\n",
                  sc->sc_bmisscount);
        sc->sc_stats.ast_bstuck++;
        ath_reset(ifp);
        wlan_serialize_exit();
}

/*
 * Reclaim beacon resources and return buffer to the pool.
 */
static void
ath_beacon_return(struct ath_softc *sc, struct ath_buf *bf)
{

        if (bf->bf_m != NULL) {
                bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
                m_freem(bf->bf_m);
                bf->bf_m = NULL;
        }
        if (bf->bf_node != NULL) {
                ieee80211_free_node(bf->bf_node);
                bf->bf_node = NULL;
        }
        STAILQ_INSERT_TAIL(&sc->sc_bbuf, bf, bf_list);
}

/*
 * Reclaim beacon resources.
 */
static void
ath_beacon_free(struct ath_softc *sc)
{
        struct ath_buf *bf;

        STAILQ_FOREACH(bf, &sc->sc_bbuf, bf_list) {
                if (bf->bf_m != NULL) {
                        bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
                        m_freem(bf->bf_m);
                        bf->bf_m = NULL;
                }
                if (bf->bf_node != NULL) {
                        ieee80211_free_node(bf->bf_node);
                        bf->bf_node = NULL;
                }
        }
}

/*
 * Configure the beacon and sleep timers.
 *
 * When operating as an AP this resets the TSF and sets
 * up the hardware to notify us when we need to issue beacons.
 *
 * When operating in station mode this sets up the beacon
 * timers according to the timestamp of the last received
 * beacon and the current TSF, configures PCF and DTIM
 * handling, programs the sleep registers so the hardware
 * will wakeup in time to receive beacons, and configures
 * the beacon miss handling so we'll receive a BMISS
 * interrupt when we stop seeing beacons from the AP
 * we've associated with.
 */
static void
ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
{
#define TSF_TO_TU(_h,_l) \
        ((((u_int32_t)(_h)) << 22) | (((u_int32_t)(_l)) >> 10))
#define FUDGE   2
        struct ath_hal *ah = sc->sc_ah;
        struct ieee80211com *ic = sc->sc_ifp->if_l2com;
        struct ieee80211_node *ni;
        u_int32_t nexttbtt, intval, tsftu;
        u_int64_t tsf;

        if (vap == NULL)
                vap = TAILQ_FIRST(&ic->ic_vaps);        /* XXX */
        ni = vap->iv_bss;

        /* extract tstamp from last beacon and convert to TU */
        nexttbtt = TSF_TO_TU(LE_READ_4(ni->ni_tstamp.data + 4),
                             LE_READ_4(ni->ni_tstamp.data));
        if (ic->ic_opmode == IEEE80211_M_HOSTAP ||
            ic->ic_opmode == IEEE80211_M_MBSS) {
                /*
                 * For multi-bss ap/mesh support beacons are either staggered
                 * evenly over N slots or burst together.  For the former
                 * arrange for the SWBA to be delivered for each slot.
                 * Slots that are not occupied will generate nothing.
                 */
                /* NB: the beacon interval is kept internally in TU's */
                intval = ni->ni_intval & HAL_BEACON_PERIOD;
                if (sc->sc_stagbeacons)
                        intval /= ATH_BCBUF;
        } else {
                /* NB: the beacon interval is kept internally in TU's */
                intval = ni->ni_intval & HAL_BEACON_PERIOD;
        }
        if (nexttbtt == 0)              /* e.g. for ap mode */
                nexttbtt = intval;
        else if (intval)                /* NB: can be 0 for monitor mode */
                nexttbtt = roundup(nexttbtt, intval);
        DPRINTF(sc, ATH_DEBUG_BEACON, "%s: nexttbtt %u intval %u (%u)\n",
                __func__, nexttbtt, intval, ni->ni_intval);
        if (ic->ic_opmode == IEEE80211_M_STA && !sc->sc_swbmiss) {
                HAL_BEACON_STATE bs;
                int dtimperiod, dtimcount;
                int cfpperiod, cfpcount;

                /*
                 * Setup dtim and cfp parameters according to
                 * last beacon we received (which may be none).
                 */
                dtimperiod = ni->ni_dtim_period;
                if (dtimperiod <= 0)            /* NB: 0 if not known */
                        dtimperiod = 1;
                dtimcount = ni->ni_dtim_count;
                if (dtimcount >= dtimperiod)    /* NB: sanity check */
                        dtimcount = 0;          /* XXX? */
                cfpperiod = 1;                  /* NB: no PCF support yet */
                cfpcount = 0;
                /*
                 * Pull nexttbtt forward to reflect the current
                 * TSF and calculate dtim+cfp state for the result.
                 */
                tsf = ath_hal_gettsf64(ah);
                tsftu = TSF_TO_TU(tsf>>32, tsf) + FUDGE;
                do {
                        nexttbtt += intval;
                        if (--dtimcount < 0) {
                                dtimcount = dtimperiod - 1;
                                if (--cfpcount < 0)
                                        cfpcount = cfpperiod - 1;
                        }
                } while (nexttbtt < tsftu);
                memset(&bs, 0, sizeof(bs));
                bs.bs_intval = intval;
                bs.bs_nexttbtt = nexttbtt;
                bs.bs_dtimperiod = dtimperiod*intval;
                bs.bs_nextdtim = bs.bs_nexttbtt + dtimcount*intval;
                bs.bs_cfpperiod = cfpperiod*bs.bs_dtimperiod;
                bs.bs_cfpnext = bs.bs_nextdtim + cfpcount*bs.bs_dtimperiod;
                bs.bs_cfpmaxduration = 0;
#if 0
                /*
                 * The 802.11 layer records the offset to the DTIM
                 * bitmap while receiving beacons; use it here to
                 * enable h/w detection of our AID being marked in
                 * the bitmap vector (to indicate frames for us are
                 * pending at the AP).
                 * XXX do DTIM handling in s/w to WAR old h/w bugs
                 * XXX enable based on h/w rev for newer chips
                 */
                bs.bs_timoffset = ni->ni_timoff;
#endif
                /*
                 * Calculate the number of consecutive beacons to miss
                 * before taking a BMISS interrupt.
                 * Note that we clamp the result to at most 10 beacons.
                 */
                bs.bs_bmissthreshold = vap->iv_bmissthreshold;
                if (bs.bs_bmissthreshold > 10)
                        bs.bs_bmissthreshold = 10;
                else if (bs.bs_bmissthreshold <= 0)
                        bs.bs_bmissthreshold = 1;

                /*
                 * Calculate sleep duration.  The configuration is
                 * given in ms.  We insure a multiple of the beacon
                 * period is used.  Also, if the sleep duration is
                 * greater than the DTIM period then it makes senses
                 * to make it a multiple of that.
                 *
                 * XXX fixed at 100ms
                 */
                bs.bs_sleepduration =
                        roundup(IEEE80211_MS_TO_TU(100), bs.bs_intval);
                if (bs.bs_sleepduration > bs.bs_dtimperiod)
                        bs.bs_sleepduration = roundup(bs.bs_sleepduration, bs.bs_dtimperiod);

                DPRINTF(sc, ATH_DEBUG_BEACON,
                        "%s: tsf %ju tsf:tu %u intval %u nexttbtt %u dtim %u nextdtim %u bmiss %u sleep %u cfp:period %u maxdur %u next %u timoffset %u\n"
                        , __func__
                        , tsf, tsftu
                        , bs.bs_intval
                        , bs.bs_nexttbtt
                        , bs.bs_dtimperiod
                        , bs.bs_nextdtim
                        , bs.bs_bmissthreshold
                        , bs.bs_sleepduration
                        , bs.bs_cfpperiod
                        , bs.bs_cfpmaxduration
                        , bs.bs_cfpnext
                        , bs.bs_timoffset
                );
                ath_hal_intrset(ah, 0);
                ath_hal_beacontimers(ah, &bs);
                sc->sc_imask |= HAL_INT_BMISS;
                ath_hal_intrset(ah, sc->sc_imask);
        } else {
                ath_hal_intrset(ah, 0);
                if (nexttbtt == intval)
                        intval |= HAL_BEACON_RESET_TSF;
                if (ic->ic_opmode == IEEE80211_M_IBSS) {
                        /*
                         * In IBSS mode enable the beacon timers but only
                         * enable SWBA interrupts if we need to manually
                         * prepare beacon frames.  Otherwise we use a
                         * self-linked tx descriptor and let the hardware
                         * deal with things.
                         */
                        intval |= HAL_BEACON_ENA;
                        if (!sc->sc_hasveol)
                                sc->sc_imask |= HAL_INT_SWBA;
                        if ((intval & HAL_BEACON_RESET_TSF) == 0) {
                                /*
                                 * Pull nexttbtt forward to reflect
                                 * the current TSF.
                                 */
                                tsf = ath_hal_gettsf64(ah);
                                tsftu = TSF_TO_TU(tsf>>32, tsf) + FUDGE;
                                do {
                                        nexttbtt += intval;
                                } while (nexttbtt < tsftu);
                        }
                        ath_beaconq_config(sc);
                } else if (ic->ic_opmode == IEEE80211_M_HOSTAP ||
                    ic->ic_opmode == IEEE80211_M_MBSS) {
                        /*
                         * In AP/mesh mode we enable the beacon timers
                         * and SWBA interrupts to prepare beacon frames.
                         */
                        intval |= HAL_BEACON_ENA;
                        sc->sc_imask |= HAL_INT_SWBA;   /* beacon prepare */
                        ath_beaconq_config(sc);
                }
                ath_hal_beaconinit(ah, nexttbtt, intval);
                sc->sc_bmisscount = 0;
                ath_hal_intrset(ah, sc->sc_imask);
                /*
                 * When using a self-linked beacon descriptor in
                 * ibss mode load it once here.
                 */
                if (ic->ic_opmode == IEEE80211_M_IBSS && sc->sc_hasveol)
                        ath_beacon_start_adhoc(sc, vap);
        }
        sc->sc_syncbeacon = 0;
#undef FUDGE
#undef TSF_TO_TU
}

static void
ath_load_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
{
        bus_addr_t *paddr = (bus_addr_t*) arg;
        KASSERT(error == 0, ("error %u on bus_dma callback", error));
        *paddr = segs->ds_addr;
}

static int
ath_descdma_setup(struct ath_softc *sc,
        struct ath_descdma *dd, ath_bufhead *head,
        const char *name, int nbuf, int ndesc)
{
#define DS2PHYS(_dd, _ds) \
        ((_dd)->dd_desc_paddr + ((caddr_t)(_ds) - (caddr_t)(_dd)->dd_desc))
        struct ifnet *ifp = sc->sc_ifp;
        struct ath_desc *ds;
        struct ath_buf *bf;
        int i, bsize, error;

        DPRINTF(sc, ATH_DEBUG_RESET, "%s: %s DMA: %u buffers %u desc/buf\n",
            __func__, name, nbuf, ndesc);

        dd->dd_name = name;
        dd->dd_desc_len = sizeof(struct ath_desc) * nbuf * ndesc;

        /*
         * Setup DMA descriptor area.
         */
        error = bus_dma_tag_create(dd->dd_dmat, /* parent */
                       PAGE_SIZE, 0,            /* alignment, bounds */
                       BUS_SPACE_MAXADDR_32BIT, /* lowaddr */
                       BUS_SPACE_MAXADDR,       /* highaddr */
                       NULL, NULL,              /* filter, filterarg */
                       dd->dd_desc_len,         /* maxsize */
                       1,                       /* nsegments */
                       dd->dd_desc_len,         /* maxsegsize */
                       BUS_DMA_ALLOCNOW,        /* flags */
                       &dd->dd_dmat);
        if (error != 0) {
                if_printf(ifp, "cannot allocate %s DMA tag\n", dd->dd_name);
                return error;
        }

        /* allocate descriptors */
        error = bus_dmamap_create(dd->dd_dmat, BUS_DMA_NOWAIT, &dd->dd_dmamap);
        if (error != 0) {
                if_printf(ifp, "unable to create dmamap for %s descriptors, "
                        "error %u\n", dd->dd_name, error);
                goto fail0;
        }

        error = bus_dmamem_alloc(dd->dd_dmat, (void**) &dd->dd_desc,
                                 BUS_DMA_NOWAIT | BUS_DMA_COHERENT, 
                                 &dd->dd_dmamap);
        if (error != 0) {
                if_printf(ifp, "unable to alloc memory for %u %s descriptors, "
                        "error %u\n", nbuf * ndesc, dd->dd_name, error);
                goto fail1;
        }

        error = bus_dmamap_load(dd->dd_dmat, dd->dd_dmamap,
                                dd->dd_desc, dd->dd_desc_len,
                                ath_load_cb, &dd->dd_desc_paddr,
                                BUS_DMA_NOWAIT);
        if (error != 0) {
                if_printf(ifp, "unable to map %s descriptors, error %u\n",
                        dd->dd_name, error);
                goto fail2;
        }

        ds = dd->dd_desc;
        DPRINTF(sc, ATH_DEBUG_RESET, "%s: %s DMA map: %p (%lu) -> %p (%lu)\n",
            __func__, dd->dd_name, ds, (u_long) dd->dd_desc_len,
            (caddr_t) dd->dd_desc_paddr, /*XXX*/ (u_long) dd->dd_desc_len);

        /* allocate rx buffers */
        bsize = sizeof(struct ath_buf) * nbuf;
        bf = kmalloc(bsize, M_ATHDEV, M_INTWAIT | M_ZERO);
        dd->dd_bufptr = bf;

        STAILQ_INIT(head);
        for (i = 0; i < nbuf; i++, bf++, ds += ndesc) {
                bf->bf_desc = ds;
                bf->bf_daddr = DS2PHYS(dd, ds);
                error = bus_dmamap_create(sc->sc_dmat, BUS_DMA_NOWAIT,
                                &bf->bf_dmamap);
                if (error != 0) {
                        if_printf(ifp, "unable to create dmamap for %s "
                                "buffer %u, error %u\n", dd->dd_name, i, error);
                        ath_descdma_cleanup(sc, dd, head);
                        return error;
                }
                STAILQ_INSERT_TAIL(head, bf, bf_list);
        }
        return 0;
fail2:
        bus_dmamem_free(dd->dd_dmat, dd->dd_desc, dd->dd_dmamap);
fail1:
        bus_dmamap_destroy(dd->dd_dmat, dd->dd_dmamap);
fail0:
        bus_dma_tag_destroy(dd->dd_dmat);
        memset(dd, 0, sizeof(*dd));
        return error;
#undef DS2PHYS
}

static void
ath_descdma_cleanup(struct ath_softc *sc,
        struct ath_descdma *dd, ath_bufhead *head)
{
        struct ath_buf *bf;
        struct ieee80211_node *ni;

        bus_dmamap_unload(dd->dd_dmat, dd->dd_dmamap);
        bus_dmamem_free(dd->dd_dmat, dd->dd_desc, dd->dd_dmamap);
        bus_dmamap_destroy(dd->dd_dmat, dd->dd_dmamap);
        bus_dma_tag_destroy(dd->dd_dmat);

        STAILQ_FOREACH(bf, head, bf_list) {
                if (bf->bf_m) {
                        m_freem(bf->bf_m);
                        bf->bf_m = NULL;
                }
                if (bf->bf_dmamap != NULL) {
                        bus_dmamap_destroy(sc->sc_dmat, bf->bf_dmamap);
                        bf->bf_dmamap = NULL;
                }
                ni = bf->bf_node;
                bf->bf_node = NULL;
                if (ni != NULL) {
                        /*
                         * Reclaim node reference.
                         */
                        ieee80211_free_node(ni);
                }
        }

        STAILQ_INIT(head);
        kfree(dd->dd_bufptr, M_ATHDEV);
        memset(dd, 0, sizeof(*dd));
}

static int
ath_desc_alloc(struct ath_softc *sc)
{
        int error;

        error = ath_descdma_setup(sc, &sc->sc_rxdma, &sc->sc_rxbuf,
                        "rx", ath_rxbuf, 1);
        if (error != 0)
                return error;

        error = ath_descdma_setup(sc, &sc->sc_txdma, &sc->sc_txbuf,
                        "tx", ath_txbuf, ATH_TXDESC);
        if (error != 0) {
                ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
                return error;
        }

        error = ath_descdma_setup(sc, &sc->sc_bdma, &sc->sc_bbuf,
                        "beacon", ATH_BCBUF, 1);
        if (error != 0) {
                ath_descdma_cleanup(sc, &sc->sc_txdma, &sc->sc_txbuf);
                ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
                return error;
        }
        return 0;
}

static void
ath_desc_free(struct ath_softc *sc)
{

        if (sc->sc_bdma.dd_desc_len != 0)
                ath_descdma_cleanup(sc, &sc->sc_bdma, &sc->sc_bbuf);
        if (sc->sc_txdma.dd_desc_len != 0)
                ath_descdma_cleanup(sc, &sc->sc_txdma, &sc->sc_txbuf);
        if (sc->sc_rxdma.dd_desc_len != 0)
                ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
}

static struct ieee80211_node *
ath_node_alloc(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN])
{
        struct ieee80211com *ic = vap->iv_ic;
        struct ath_softc *sc = ic->ic_ifp->if_softc;
        const size_t space = sizeof(struct ath_node) + sc->sc_rc->arc_space;
        struct ath_node *an;

        an = kmalloc(space, M_80211_NODE, M_INTWAIT|M_ZERO);
        ath_rate_node_init(sc, an);

        DPRINTF(sc, ATH_DEBUG_NODE, "%s: an %p\n", __func__, an);
        return &an->an_node;
}

static void
ath_node_free(struct ieee80211_node *ni)
{
        struct ieee80211com *ic = ni->ni_ic;
        struct ath_softc *sc = ic->ic_ifp->if_softc;

        DPRINTF(sc, ATH_DEBUG_NODE, "%s: ni %p\n", __func__, ni);

        ath_rate_node_cleanup(sc, ATH_NODE(ni));
        sc->sc_node_free(ni);
}

static void
ath_node_getsignal(const struct ieee80211_node *ni, int8_t *rssi, int8_t *noise)
{
        struct ieee80211com *ic = ni->ni_ic;
        struct ath_softc *sc = ic->ic_ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;

        *rssi = ic->ic_node_getrssi(ni);
        if (ni->ni_chan != IEEE80211_CHAN_ANYC)
                *noise = ath_hal_getchannoise(ah, ni->ni_chan);
        else
                *noise = -95;           /* nominally correct */
}

static int
ath_rxbuf_init(struct ath_softc *sc, struct ath_buf *bf)
{
        struct ath_hal *ah = sc->sc_ah;
        int error;
        struct mbuf *m;
        struct ath_desc *ds;

        m = bf->bf_m;
        if (m == NULL) {
                /*
                 * NB: by assigning a page to the rx dma buffer we
                 * implicitly satisfy the Atheros requirement that
                 * this buffer be cache-line-aligned and sized to be
                 * multiple of the cache line size.  Not doing this
                 * causes weird stuff to happen (for the 5210 at least).
                 */
                m = m_getcl(MB_WAIT, MT_DATA, M_PKTHDR);
                if (m == NULL) {
                        kprintf("ath_rxbuf_init: no mbuf\n");
                        DPRINTF(sc, ATH_DEBUG_ANY,
                                "%s: no mbuf/cluster\n", __func__);
                        sc->sc_stats.ast_rx_nombuf++;
                        return ENOMEM;
                }
                m->m_pkthdr.len = m->m_len = m->m_ext.ext_size;

                error = bus_dmamap_load_mbuf_segment(sc->sc_dmat,
                                             bf->bf_dmamap, m,
                                             bf->bf_segs, 1, &bf->bf_nseg,
                                             BUS_DMA_NOWAIT);
                if (error != 0) {
                        DPRINTF(sc, ATH_DEBUG_ANY,
                            "%s: bus_dmamap_load_mbuf_segment failed; error %d\n",
                            __func__, error);
                        sc->sc_stats.ast_rx_busdma++;
                        m_freem(m);
                        return error;
                }
                KASSERT(bf->bf_nseg == 1,
                        ("multi-segment packet; nseg %u", bf->bf_nseg));
                bf->bf_m = m;
        }
        bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREREAD);

        /*
         * Setup descriptors.  For receive we always terminate
         * the descriptor list with a self-linked entry so we'll
         * not get overrun under high load (as can happen with a
         * 5212 when ANI processing enables PHY error frames).
         *
         * To insure the last descriptor is self-linked we create
         * each descriptor as self-linked and add it to the end.  As
         * each additional descriptor is added the previous self-linked
         * entry is ``fixed'' naturally.  This should be safe even
         * if DMA is happening.  When processing RX interrupts we
         * never remove/process the last, self-linked, entry on the
         * descriptor list.  This insures the hardware always has
         * someplace to write a new frame.
         */
        ds = bf->bf_desc;
        ds->ds_link = bf->bf_daddr;     /* link to self */
        ds->ds_data = bf->bf_segs[0].ds_addr;
        ath_hal_setuprxdesc(ah, ds
                , m->m_len              /* buffer size */
                , 0
        );

        if (sc->sc_rxlink != NULL)
                *sc->sc_rxlink = bf->bf_daddr;
        sc->sc_rxlink = &ds->ds_link;
        return 0;
}

/*
 * Extend 15-bit time stamp from rx descriptor to
 * a full 64-bit TSF using the specified TSF.
 */
static __inline u_int64_t
ath_extend_tsf(u_int32_t rstamp, u_int64_t tsf)
{
        if ((tsf & 0x7fff) < rstamp)
                tsf -= 0x8000;
        return ((tsf &~ 0x7fff) | rstamp);
}

/*
 * Intercept management frames to collect beacon rssi data
 * and to do ibss merges.
 */
static void
ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
        int subtype, int rssi, int nf)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;

        /*
         * Call up first so subsequent work can use information
         * potentially stored in the node (e.g. for ibss merge).
         */
        ATH_VAP(vap)->av_recv_mgmt(ni, m, subtype, rssi, nf);
        switch (subtype) {
        case IEEE80211_FC0_SUBTYPE_BEACON:
                /* update rssi statistics for use by the hal */
                ATH_RSSI_LPF(sc->sc_halstats.ns_avgbrssi, rssi);
                if (sc->sc_syncbeacon &&
                    ni == vap->iv_bss && vap->iv_state == IEEE80211_S_RUN) {
                        /*
                         * Resync beacon timers using the tsf of the beacon
                         * frame we just received.
                         */
                        ath_beacon_config(sc, vap);
                }
                /* fall thru... */
        case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
                if (vap->iv_opmode == IEEE80211_M_IBSS &&
                    vap->iv_state == IEEE80211_S_RUN) {
                        uint32_t rstamp = sc->sc_lastrs->rs_tstamp;
                        u_int64_t tsf = ath_extend_tsf(rstamp,
                                ath_hal_gettsf64(sc->sc_ah));
                        /*
                         * Handle ibss merge as needed; check the tsf on the
                         * frame before attempting the merge.  The 802.11 spec
                         * says the station should change it's bssid to match
                         * the oldest station with the same ssid, where oldest
                         * is determined by the tsf.  Note that hardware
                         * reconfiguration happens through callback to
                         * ath_newstate as the state machine will go from
                         * RUN -> RUN when this happens.
                         */
                        if (le64toh(ni->ni_tstamp.tsf) >= tsf) {
                                DPRINTF(sc, ATH_DEBUG_STATE,
                                    "ibss merge, rstamp %u tsf %ju "
                                    "tstamp %ju\n", rstamp, (uintmax_t)tsf,
                                    (uintmax_t)ni->ni_tstamp.tsf);
                                (void) ieee80211_ibss_merge(ni);
                        }
                }
                break;
        }
}

/*
 * Set the default antenna.
 */
static void
ath_setdefantenna(struct ath_softc *sc, u_int antenna)
{
        struct ath_hal *ah = sc->sc_ah;

        /* XXX block beacon interrupts */
        ath_hal_setdefantenna(ah, antenna);
        if (sc->sc_defant != antenna)
                sc->sc_stats.ast_ant_defswitch++;
        sc->sc_defant = antenna;
        sc->sc_rxotherant = 0;
}

static void
ath_rx_tap(struct ifnet *ifp, struct mbuf *m,
        const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
{
#define CHAN_HT20       htole32(IEEE80211_CHAN_HT20)
#define CHAN_HT40U      htole32(IEEE80211_CHAN_HT40U)
#define CHAN_HT40D      htole32(IEEE80211_CHAN_HT40D)
#define CHAN_HT         (CHAN_HT20|CHAN_HT40U|CHAN_HT40D)
        struct ath_softc *sc = ifp->if_softc;
        const HAL_RATE_TABLE *rt;
        uint8_t rix;

        rt = sc->sc_currates;
        KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
        rix = rt->rateCodeToIndex[rs->rs_rate];
        sc->sc_rx_th.wr_rate = sc->sc_hwmap[rix].ieeerate;
        sc->sc_rx_th.wr_flags = sc->sc_hwmap[rix].rxflags;
#ifdef AH_SUPPORT_AR5416
        sc->sc_rx_th.wr_chan_flags &= ~CHAN_HT;
        if (sc->sc_rx_th.wr_rate & IEEE80211_RATE_MCS) {        /* HT rate */
                struct ieee80211com *ic = ifp->if_l2com;

                if ((rs->rs_flags & HAL_RX_2040) == 0)
                        sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
                else if (IEEE80211_IS_CHAN_HT40U(ic->ic_curchan))
                        sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
                else
                        sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
                if ((rs->rs_flags & HAL_RX_GI) == 0)
                        sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_SHORTGI;
        }
#endif
        sc->sc_rx_th.wr_tsf = htole64(ath_extend_tsf(rs->rs_tstamp, tsf));
        if (rs->rs_status & HAL_RXERR_CRC)
                sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_BADFCS;
        /* XXX propagate other error flags from descriptor */
        sc->sc_rx_th.wr_antnoise = nf;
        sc->sc_rx_th.wr_antsignal = nf + rs->rs_rssi;
        sc->sc_rx_th.wr_antenna = rs->rs_antenna;
#undef CHAN_HT
#undef CHAN_HT20
#undef CHAN_HT40U
#undef CHAN_HT40D
}

static void
ath_handle_micerror(struct ieee80211com *ic,
        struct ieee80211_frame *wh, int keyix)
{
        struct ieee80211_node *ni;

        /* XXX recheck MIC to deal w/ chips that lie */
        /* XXX discard MIC errors on !data frames */
        ni = ieee80211_find_rxnode(ic, (const struct ieee80211_frame_min *) wh);
        if (ni != NULL) {
                ieee80211_notify_michael_failure(ni->ni_vap, wh, keyix);
                ieee80211_free_node(ni);
        }
}

static void
ath_rx_task(void *arg, int npending)
{
#define PA2DESC(_sc, _pa) \
        ((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
                ((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
        struct ath_softc *sc = arg;
        struct ath_buf *bf;
        struct ifnet *ifp;
        struct ieee80211com *ic;
        struct ath_hal *ah;
        struct ath_desc *ds;
        struct ath_rx_status *rs;
        struct mbuf *m;
        struct ieee80211_node *ni;
        int len, type, ngood;
        u_int phyerr;
        HAL_STATUS status;
        int16_t nf;
        u_int64_t tsf;

        wlan_serialize_enter();
        ifp = sc->sc_ifp;
        ic = ifp->if_l2com;
        ah = sc->sc_ah;

        DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: pending %u\n", __func__, npending);
        ngood = 0;
        nf = ath_hal_getchannoise(ah, sc->sc_curchan);
        sc->sc_stats.ast_rx_noise = nf;
        tsf = ath_hal_gettsf64(ah);
        do {
                bf = STAILQ_FIRST(&sc->sc_rxbuf);
                if (bf == NULL) {               /* NB: shouldn't happen */
                        if_printf(ifp, "%s: no buffer!\n", __func__);
                        break;
                }
                m = bf->bf_m;
                if (m == NULL) {                /* NB: shouldn't happen */
                        /*
                         * If mbuf allocation failed previously there
                         * will be no mbuf; try again to re-populate it.
                         */ 
                        /* XXX make debug msg */
                        if_printf(ifp, "%s: no mbuf!\n", __func__);
                        STAILQ_REMOVE_HEAD(&sc->sc_rxbuf, bf_list);
                        goto rx_next;
                }
                ds = bf->bf_desc;
                if (ds->ds_link == bf->bf_daddr) {
                        /* NB: never process the self-linked entry at the end */
                        break;
                }
                /* XXX sync descriptor memory */
                /*
                 * Must provide the virtual address of the current
                 * descriptor, the physical address, and the virtual
                 * address of the next descriptor in the h/w chain.
                 * This allows the HAL to look ahead to see if the
                 * hardware is done with a descriptor by checking the
                 * done bit in the following descriptor and the address
                 * of the current descriptor the DMA engine is working
                 * on.  All this is necessary because of our use of
                 * a self-linked list to avoid rx overruns.
                 */
                rs = &bf->bf_status.ds_rxstat;
                status = ath_hal_rxprocdesc(ah, ds,
                                bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
#ifdef ATH_DEBUG
                if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
                        ath_printrxbuf(sc, bf, 0, status == HAL_OK);
#endif
                if (status == HAL_EINPROGRESS)
                        break;
                STAILQ_REMOVE_HEAD(&sc->sc_rxbuf, bf_list);
                if (rs->rs_status != 0) {
                        if (rs->rs_status & HAL_RXERR_CRC)
                                sc->sc_stats.ast_rx_crcerr++;
                        if (rs->rs_status & HAL_RXERR_FIFO)
                                sc->sc_stats.ast_rx_fifoerr++;
                        if (rs->rs_status & HAL_RXERR_PHY) {
                                sc->sc_stats.ast_rx_phyerr++;
                                phyerr = rs->rs_phyerr & 0x1f;
                                sc->sc_stats.ast_rx_phy[phyerr]++;
                                goto rx_error;  /* NB: don't count in ierrors */
                        }
                        if (rs->rs_status & HAL_RXERR_DECRYPT) {
                                /*
                                 * Decrypt error.  If the error occurred
                                 * because there was no hardware key, then
                                 * let the frame through so the upper layers
                                 * can process it.  This is necessary for 5210
                                 * parts which have no way to setup a ``clear''
                                 * key cache entry.
                                 *
                                 * XXX do key cache faulting
                                 */
                                if (rs->rs_keyix == HAL_RXKEYIX_INVALID)
                                        goto rx_accept;
                                sc->sc_stats.ast_rx_badcrypt++;
                        }
                        if (rs->rs_status & HAL_RXERR_MIC) {
                                sc->sc_stats.ast_rx_badmic++;
                                /*
                                 * Do minimal work required to hand off
                                 * the 802.11 header for notification.
                                 */
                                /* XXX frag's and qos frames */
                                len = rs->rs_datalen;
                                if (len >= sizeof (struct ieee80211_frame)) {
                                        bus_dmamap_sync(sc->sc_dmat,
                                            bf->bf_dmamap,
                                            BUS_DMASYNC_POSTREAD);
                                        ath_handle_micerror(ic, 
                                            mtod(m, struct ieee80211_frame *),
                                            sc->sc_splitmic ?
                                                rs->rs_keyix-32 : rs->rs_keyix);
                                }
                        }
                        ifp->if_ierrors++;
rx_error:
                        /*
                         * Cleanup any pending partial frame.
                         */
                        if (sc->sc_rxpending != NULL) {
                                m_freem(sc->sc_rxpending);
                                sc->sc_rxpending = NULL;
                        }
                        /*
                         * When a tap is present pass error frames
                         * that have been requested.  By default we
                         * pass decrypt+mic errors but others may be
                         * interesting (e.g. crc).
                         */
                        if (ieee80211_radiotap_active(ic) &&
                            (rs->rs_status & sc->sc_monpass)) {
                                bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
                                    BUS_DMASYNC_POSTREAD);
                                /* NB: bpf needs the mbuf length setup */
                                len = rs->rs_datalen;
                                m->m_pkthdr.len = m->m_len = len;
                                ath_rx_tap(ifp, m, rs, tsf, nf);
                                ieee80211_radiotap_rx_all(ic, m);
                        }
                        /* XXX pass MIC errors up for s/w reclaculation */
                        goto rx_next;
                }
rx_accept:
                /*
                 * Sync and unmap the frame.  At this point we're
                 * committed to passing the mbuf somewhere so clear
                 * bf_m; this means a new mbuf must be allocated
                 * when the rx descriptor is setup again to receive
                 * another frame.
                 */
                bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
                    BUS_DMASYNC_POSTREAD);
                bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
                bf->bf_m = NULL;

                len = rs->rs_datalen;
                m->m_len = len;

                if (rs->rs_more) {
                        /*
                         * Frame spans multiple descriptors; save
                         * it for the next completed descriptor, it
                         * will be used to construct a jumbogram.
                         */
                        if (sc->sc_rxpending != NULL) {
                                /* NB: max frame size is currently 2 clusters */
                                sc->sc_stats.ast_rx_toobig++;
                                m_freem(sc->sc_rxpending);
                        }
                        m->m_pkthdr.rcvif = ifp;
                        m->m_pkthdr.len = len;
                        sc->sc_rxpending = m;
                        goto rx_next;
                } else if (sc->sc_rxpending != NULL) {
                        /*
                         * This is the second part of a jumbogram,
                         * chain it to the first mbuf, adjust the
                         * frame length, and clear the rxpending state.
                         */
                        sc->sc_rxpending->m_next = m;
                        sc->sc_rxpending->m_pkthdr.len += len;
                        m = sc->sc_rxpending;
                        sc->sc_rxpending = NULL;
                } else {
                        /*
                         * Normal single-descriptor receive; setup
                         * the rcvif and packet length.
                         */
                        m->m_pkthdr.rcvif = ifp;
                        m->m_pkthdr.len = len;
                }

                ifp->if_ipackets++;
                sc->sc_stats.ast_ant_rx[rs->rs_antenna]++;

                /*
                 * Populate the rx status block.  When there are bpf
                 * listeners we do the additional work to provide
                 * complete status.  Otherwise we fill in only the
                 * material required by ieee80211_input.  Note that
                 * noise setting is filled in above.
                 */
                if (ieee80211_radiotap_active(ic))
                        ath_rx_tap(ifp, m, rs, tsf, nf);

                /*
                 * From this point on we assume the frame is at least
                 * as large as ieee80211_frame_min; verify that.
                 */
                if (len < IEEE80211_MIN_LEN) {
                        if (!ieee80211_radiotap_active(ic)) {
                                DPRINTF(sc, ATH_DEBUG_RECV,
                                    "%s: short packet %d\n", __func__, len);
                                sc->sc_stats.ast_rx_tooshort++;
                        } else {
                                /* NB: in particular this captures ack's */
                                ieee80211_radiotap_rx_all(ic, m);
                        }
                        m_freem(m);
                        goto rx_next;
                }

                if (IFF_DUMPPKTS(sc, ATH_DEBUG_RECV)) {
                        const HAL_RATE_TABLE *rt = sc->sc_currates;
                        uint8_t rix = rt->rateCodeToIndex[rs->rs_rate];

                        ieee80211_dump_pkt(ic, mtod(m, caddr_t), len,
                            sc->sc_hwmap[rix].ieeerate, rs->rs_rssi);
                }

                m_adj(m, -IEEE80211_CRC_LEN);

                /*
                 * Locate the node for sender, track state, and then
                 * pass the (referenced) node up to the 802.11 layer
                 * for its use.
                 */
                ni = ieee80211_find_rxnode_withkey(ic,
                        mtod(m, const struct ieee80211_frame_min *),
                        rs->rs_keyix == HAL_RXKEYIX_INVALID ?
                                IEEE80211_KEYIX_NONE : rs->rs_keyix);
                if (ni != NULL) {
                        /*
                         * Sending station is known, dispatch directly.
                         */
                        sc->sc_lastrs = rs;
                        type = ieee80211_input(ni, m, rs->rs_rssi, nf);
                        ieee80211_free_node(ni);
                        /*
                         * Arrange to update the last rx timestamp only for
                         * frames from our ap when operating in station mode.
                         * This assumes the rx key is always setup when
                         * associated.
                         */
                        if (ic->ic_opmode == IEEE80211_M_STA &&
                            rs->rs_keyix != HAL_RXKEYIX_INVALID)
                                ngood++;
                } else {
                        type = ieee80211_input_all(ic, m, rs->rs_rssi, nf);
                }
                /*
                 * Track rx rssi and do any rx antenna management.
                 */
                ATH_RSSI_LPF(sc->sc_halstats.ns_avgrssi, rs->rs_rssi);
                if (sc->sc_diversity) {
                        /*
                         * When using fast diversity, change the default rx
                         * antenna if diversity chooses the other antenna 3
                         * times in a row.
                         */
                        if (sc->sc_defant != rs->rs_antenna) {
                                if (++sc->sc_rxotherant >= 3)
                                        ath_setdefantenna(sc, rs->rs_antenna);
                        } else
                                sc->sc_rxotherant = 0;
                }
                if (sc->sc_softled) {
                        /*
                         * Blink for any data frame.  Otherwise do a
                         * heartbeat-style blink when idle.  The latter
                         * is mainly for station mode where we depend on
                         * periodic beacon frames to trigger the poll event.
                         */
                        if (type == IEEE80211_FC0_TYPE_DATA) {
                                const HAL_RATE_TABLE *rt = sc->sc_currates;
                                ath_led_event(sc, 
                                    rt->rateCodeToIndex[rs->rs_rate]);
                        } else if (ticks - sc->sc_ledevent >= sc->sc_ledidle)
                                ath_led_event(sc, 0);
                }
rx_next:
                STAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
        } while (ath_rxbuf_init(sc, bf) == 0);

        /* rx signal state monitoring */
        ath_hal_rxmonitor(ah, &sc->sc_halstats, sc->sc_curchan);
        if (ngood)
                sc->sc_lastrx = tsf;

        if ((ifp->if_flags & IFF_OACTIVE) == 0) {
#ifdef IEEE80211_SUPPORT_SUPERG
                ieee80211_ff_age_all(ic, 100);
#endif
                if (!ifq_is_empty(&ifp->if_snd))
                        ath_start(ifp);
        }
        wlan_serialize_exit();
#undef PA2DESC
}

static void
ath_txq_init(struct ath_softc *sc, struct ath_txq *txq, int qnum)
{
        txq->axq_qnum = qnum;
        txq->axq_ac = 0;
        txq->axq_depth = 0;
        txq->axq_intrcnt = 0;
        txq->axq_link = NULL;
        STAILQ_INIT(&txq->axq_q);
}

/*
 * Setup a h/w transmit queue.
 */
static struct ath_txq *
ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
{
        struct ath_hal *ah = sc->sc_ah;
        HAL_TXQ_INFO qi;
        int qnum;

        memset(&qi, 0, sizeof(qi));
        qi.tqi_subtype = subtype;
        qi.tqi_aifs = HAL_TXQ_USEDEFAULT;
        qi.tqi_cwmin = HAL_TXQ_USEDEFAULT;
        qi.tqi_cwmax = HAL_TXQ_USEDEFAULT;
        /*
         * Enable interrupts only for EOL and DESC conditions.
         * We mark tx descriptors to receive a DESC interrupt
         * when a tx queue gets deep; otherwise waiting for the
         * EOL to reap descriptors.  Note that this is done to
         * reduce interrupt load and this only defers reaping
         * descriptors, never transmitting frames.  Aside from
         * reducing interrupts this also permits more concurrency.
         * The only potential downside is if the tx queue backs
         * up in which case the top half of the kernel may backup
         * due to a lack of tx descriptors.
         */
        qi.tqi_qflags = HAL_TXQ_TXEOLINT_ENABLE | HAL_TXQ_TXDESCINT_ENABLE;
        qnum = ath_hal_setuptxqueue(ah, qtype, &qi);
        if (qnum == -1) {
                /*
                 * NB: don't print a message, this happens
                 * normally on parts with too few tx queues
                 */
                return NULL;
        }
        if (qnum >= NELEM(sc->sc_txq)) {
                device_printf(sc->sc_dev,
                        "hal qnum %u out of range, max %zu!\n",
                        qnum, NELEM(sc->sc_txq));
                ath_hal_releasetxqueue(ah, qnum);
                return NULL;
        }
        if (!ATH_TXQ_SETUP(sc, qnum)) {
                ath_txq_init(sc, &sc->sc_txq[qnum], qnum);
                sc->sc_txqsetup |= 1<<qnum;
        }
        return &sc->sc_txq[qnum];
}

/*
 * Setup a hardware data transmit queue for the specified
 * access control.  The hal may not support all requested
 * queues in which case it will return a reference to a
 * previously setup queue.  We record the mapping from ac's
 * to h/w queues for use by ath_tx_start and also track
 * the set of h/w queues being used to optimize work in the
 * transmit interrupt handler and related routines.
 */
static int
ath_tx_setup(struct ath_softc *sc, int ac, int haltype)
{
        struct ath_txq *txq;

        if (ac >= NELEM(sc->sc_ac2q)) {
                device_printf(sc->sc_dev, "AC %u out of range, max %zu!\n",
                        ac, NELEM(sc->sc_ac2q));
                return 0;
        }
        txq = ath_txq_setup(sc, HAL_TX_QUEUE_DATA, haltype);
        if (txq != NULL) {
                txq->axq_ac = ac;
                sc->sc_ac2q[ac] = txq;
                return 1;
        } else
                return 0;
}

/*
 * Update WME parameters for a transmit queue.
 */
static int
ath_txq_update(struct ath_softc *sc, int ac)
{
#define ATH_EXPONENT_TO_VALUE(v)        ((1<<v)-1)
#define ATH_TXOP_TO_US(v)               (v<<5)
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_txq *txq = sc->sc_ac2q[ac];
        struct wmeParams *wmep = &ic->ic_wme.wme_chanParams.cap_wmeParams[ac];
        struct ath_hal *ah = sc->sc_ah;
        HAL_TXQ_INFO qi;

        ath_hal_gettxqueueprops(ah, txq->axq_qnum, &qi);
#ifdef IEEE80211_SUPPORT_TDMA
        if (sc->sc_tdma) {
                /*
                 * AIFS is zero so there's no pre-transmit wait.  The
                 * burst time defines the slot duration and is configured
                 * through net80211.  The QCU is setup to not do post-xmit
                 * back off, lockout all lower-priority QCU's, and fire
                 * off the DMA beacon alert timer which is setup based
                 * on the slot configuration.
                 */
                qi.tqi_qflags = HAL_TXQ_TXOKINT_ENABLE
                              | HAL_TXQ_TXERRINT_ENABLE
                              | HAL_TXQ_TXURNINT_ENABLE
                              | HAL_TXQ_TXEOLINT_ENABLE
                              | HAL_TXQ_DBA_GATED
                              | HAL_TXQ_BACKOFF_DISABLE
                              | HAL_TXQ_ARB_LOCKOUT_GLOBAL
                              ;
                qi.tqi_aifs = 0;
                /* XXX +dbaprep? */
                qi.tqi_readyTime = sc->sc_tdmaslotlen;
                qi.tqi_burstTime = qi.tqi_readyTime;
        } else {
#endif
                qi.tqi_qflags = HAL_TXQ_TXOKINT_ENABLE
                              | HAL_TXQ_TXERRINT_ENABLE
                              | HAL_TXQ_TXDESCINT_ENABLE
                              | HAL_TXQ_TXURNINT_ENABLE
                              ;
                qi.tqi_aifs = wmep->wmep_aifsn;
                qi.tqi_cwmin = ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmin);
                qi.tqi_cwmax = ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmax);
                qi.tqi_readyTime = 0;
                qi.tqi_burstTime = ATH_TXOP_TO_US(wmep->wmep_txopLimit);
#ifdef IEEE80211_SUPPORT_TDMA
        }
#endif

        DPRINTF(sc, ATH_DEBUG_RESET,
            "%s: Q%u qflags 0x%x aifs %u cwmin %u cwmax %u burstTime %u\n",
            __func__, txq->axq_qnum, qi.tqi_qflags,
            qi.tqi_aifs, qi.tqi_cwmin, qi.tqi_cwmax, qi.tqi_burstTime);

        if (!ath_hal_settxqueueprops(ah, txq->axq_qnum, &qi)) {
                if_printf(ifp, "unable to update hardware queue "
                        "parameters for %s traffic!\n",
                        ieee80211_wme_acnames[ac]);
                return 0;
        } else {
                ath_hal_resettxqueue(ah, txq->axq_qnum); /* push to h/w */
                return 1;
        }
#undef ATH_TXOP_TO_US
#undef ATH_EXPONENT_TO_VALUE
}

/*
 * Callback from the 802.11 layer to update WME parameters.
 */
static int
ath_wme_update(struct ieee80211com *ic)
{
        struct ath_softc *sc = ic->ic_ifp->if_softc;

        return !ath_txq_update(sc, WME_AC_BE) ||
            !ath_txq_update(sc, WME_AC_BK) ||
            !ath_txq_update(sc, WME_AC_VI) ||
            !ath_txq_update(sc, WME_AC_VO) ? EIO : 0;
}

/*
 * Reclaim resources for a setup queue.
 */
static void
ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
{

        ath_hal_releasetxqueue(sc->sc_ah, txq->axq_qnum);
        sc->sc_txqsetup &= ~(1<<txq->axq_qnum);
}

/*
 * Reclaim all tx queue resources.
 */
static void
ath_tx_cleanup(struct ath_softc *sc)
{
        int i;

        for (i = 0; i < HAL_NUM_TX_QUEUES; i++)
                if (ATH_TXQ_SETUP(sc, i))
                        ath_tx_cleanupq(sc, &sc->sc_txq[i]);
}

/*
 * Return h/w rate index for an IEEE rate (w/o basic rate bit)
 * using the current rates in sc_rixmap.
 */
static __inline int
ath_tx_findrix(const struct ath_softc *sc, uint8_t rate)
{
        int rix = sc->sc_rixmap[rate];
        /* NB: return lowest rix for invalid rate */
        return (rix == 0xff ? 0 : rix);
}

/*
 * Reclaim mbuf resources.  For fragmented frames we
 * need to claim each frag chained with m_nextpkt.
 */
static void
ath_freetx(struct mbuf *m)
{
        struct mbuf *next;

        do {
                next = m->m_nextpkt;
                m->m_nextpkt = NULL;
                m_freem(m);
        } while ((m = next) != NULL);
}

static int
ath_tx_dmasetup(struct ath_softc *sc, struct ath_buf *bf, struct mbuf *m0)
{
        int error;

        /*
         * 
         * Load the DMA map so any coalescing is done.  This
         * also calculates the number of descriptors we need.
         */
        error = bus_dmamap_load_mbuf_defrag(sc->sc_dmat, bf->bf_dmamap, &m0,
                                     bf->bf_segs, ATH_TXDESC,
                                     &bf->bf_nseg, BUS_DMA_NOWAIT);
        if (error != 0) {
                sc->sc_stats.ast_tx_busdma++;
                ath_freetx(m0);
                return error;
        }

        /*
         * Discard null packets.
         */
        if (bf->bf_nseg == 0) {         /* null packet, discard */
                sc->sc_stats.ast_tx_nodata++;
                ath_freetx(m0);
                return EIO;
        }
        DPRINTF(sc, ATH_DEBUG_XMIT, "%s: m %p len %u\n",
                __func__, m0, m0->m_pkthdr.len);
        bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);
        bf->bf_m = m0;

        return 0;
}

static void
ath_tx_handoff(struct ath_softc *sc, struct ath_txq *txq, struct ath_buf *bf)
{
        struct ath_hal *ah = sc->sc_ah;
        struct ath_desc *ds, *ds0;
        int i;

        /*
         * Fillin the remainder of the descriptor info.
         */
        ds0 = ds = bf->bf_desc;
        for (i = 0; i < bf->bf_nseg; i++, ds++) {
                ds->ds_data = bf->bf_segs[i].ds_addr;
                if (i == bf->bf_nseg - 1)
                        ds->ds_link = 0;
                else
                        ds->ds_link = bf->bf_daddr + sizeof(*ds) * (i + 1);
                ath_hal_filltxdesc(ah, ds
                        , bf->bf_segs[i].ds_len /* segment length */
                        , i == 0                /* first segment */
                        , i == bf->bf_nseg - 1  /* last segment */
                        , ds0                   /* first descriptor */
                );
                DPRINTF(sc, ATH_DEBUG_XMIT,
                        "%s: %d: %08x %08x %08x %08x %08x %08x\n",
                        __func__, i, ds->ds_link, ds->ds_data,
                        ds->ds_ctl0, ds->ds_ctl1, ds->ds_hw[0], ds->ds_hw[1]);
        }
        /*
         * Insert the frame on the outbound list and pass it on
         * to the hardware.  Multicast frames buffered for power
         * save stations and transmit from the CAB queue are stored
         * on a s/w only queue and loaded on to the CAB queue in
         * the SWBA handler since frames only go out on DTIM and
         * to avoid possible races.
         */
        KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
             ("busy status 0x%x", bf->bf_flags));
        if (txq->axq_qnum != ATH_TXQ_SWQ) {
#ifdef IEEE80211_SUPPORT_TDMA
                /*
                 * Supporting transmit dma.  If the queue is busy it is
                 * impossible to determine if we've won the race against
                 * the chipset checking the link field or not, so we don't
                 * try.  Instead we let the TX interrupt detect the case
                 * and restart the transmitter.
                 *
                 * If the queue is not busy we can start things rolling
                 * right here.
                 */
                int qbusy;

                ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
                qbusy = ath_hal_txqenabled(ah, txq->axq_qnum);

                if (qbusy == 0) {
                        if (txq->axq_link != NULL) {
                                /*
                                 * We had already started one previously but
                                 * not yet processed the TX interrupt.  Don't
                                 * try to race a restart because we do not
                                 * know where it stopped, let the TX interrupt
                                 * restart us when it figures out where we
                                 * stopped.
                                 */
                                cpu_sfence();
                                *txq->axq_link = bf->bf_daddr;
                                txq->axq_flags |= ATH_TXQ_PUTPENDING;
                        } else {
                                /*
                                 * We are first in line, we can safely start
                                 * at this address.
                                 */
                                cpu_sfence();
                                ath_hal_puttxbuf(ah, txq->axq_qnum,
                                                 bf->bf_daddr);
                        }
                } else {
                        /*
                         * The queue is busy, go ahead and link us in but
                         * do not try to start/restart the tx.  We just
                         * don't know whether it will pick up our link
                         * or not and we don't want to double-xmit.
                         */
                        if (txq->axq_link != NULL) {
                                cpu_sfence();
                                *txq->axq_link = bf->bf_daddr;
                        }
                        txq->axq_flags |= ATH_TXQ_PUTPENDING;
                }
#if 0
                                ath_hal_puttxbuf(ah, txq->axq_qnum,
                                        STAILQ_FIRST(&txq->axq_q)->bf_daddr);
#endif
#else
                ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
                if (txq->axq_link == NULL) {
                        ath_hal_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
                        DPRINTF(sc, ATH_DEBUG_XMIT,
                            "%s: TXDP[%u] = %p (%p) depth %d\n",
                            __func__, txq->axq_qnum,
                            (caddr_t)bf->bf_daddr, bf->bf_desc,
                            txq->axq_depth);
                } else {
                        *txq->axq_link = bf->bf_daddr;
                        DPRINTF(sc, ATH_DEBUG_XMIT,
                            "%s: link[%u](%p)=%p (%p) depth %d\n", __func__,
                            txq->axq_qnum, txq->axq_link,
                            (caddr_t)bf->bf_daddr, bf->bf_desc, txq->axq_depth);
                }
#endif /* IEEE80211_SUPPORT_TDMA */
                txq->axq_link = &bf->bf_desc[bf->bf_nseg - 1].ds_link;
                ath_hal_txstart(ah, txq->axq_qnum);
        } else {
                if (txq->axq_link != NULL) {
                        struct ath_buf *last = ATH_TXQ_LAST(txq);
                        struct ieee80211_frame *wh;

                        /* mark previous frame */
                        wh = mtod(last->bf_m, struct ieee80211_frame *);
                        wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
                        bus_dmamap_sync(sc->sc_dmat, last->bf_dmamap,
                            BUS_DMASYNC_PREWRITE);

                        /* link descriptor */
                        *txq->axq_link = bf->bf_daddr;
                }
                ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
                txq->axq_link = &bf->bf_desc[bf->bf_nseg - 1].ds_link;
        }
}

static int
ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni, struct ath_buf *bf,
    struct mbuf *m0)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct ath_vap *avp = ATH_VAP(vap);
        struct ath_hal *ah = sc->sc_ah;
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        const struct chanAccParams *cap = &ic->ic_wme.wme_chanParams;
        int error, iswep, ismcast, isfrag, ismrr;
        int keyix, hdrlen, pktlen, try0;
        u_int8_t rix, txrate, ctsrate;
        u_int8_t cix = 0xff;            /* NB: silence compiler */
        struct ath_desc *ds;
        struct ath_txq *txq;
        struct ieee80211_frame *wh;
        u_int subtype, flags, ctsduration;
        HAL_PKT_TYPE atype;
        const HAL_RATE_TABLE *rt;
        HAL_BOOL shortPreamble;
        struct ath_node *an;
        u_int pri;

        wh = mtod(m0, struct ieee80211_frame *);
        iswep = wh->i_fc[1] & IEEE80211_FC1_WEP;
        ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
        isfrag = m0->m_flags & M_FRAG;
        hdrlen = ieee80211_anyhdrsize(wh);
        /*
         * Packet length must not include any
         * pad bytes; deduct them here.
         */
        pktlen = m0->m_pkthdr.len - (hdrlen & 3);

        if (iswep) {
                const struct ieee80211_cipher *cip;
                struct ieee80211_key *k;

                /*
                 * Construct the 802.11 header+trailer for an encrypted
                 * frame. The only reason this can fail is because of an
                 * unknown or unsupported cipher/key type.
                 */
                k = ieee80211_crypto_encap(ni, m0);
                if (k == NULL) {
                        /*
                         * This can happen when the key is yanked after the
                         * frame was queued.  Just discard the frame; the
                         * 802.11 layer counts failures and provides
                         * debugging/diagnostics.
                         */
                        ath_freetx(m0);
                        return EIO;
                }
                /*
                 * Adjust the packet + header lengths for the crypto
                 * additions and calculate the h/w key index.  When
                 * a s/w mic is done the frame will have had any mic
                 * added to it prior to entry so m0->m_pkthdr.len will
                 * account for it. Otherwise we need to add it to the
                 * packet length.
                 */
                cip = k->wk_cipher;
                hdrlen += cip->ic_header;
                pktlen += cip->ic_header + cip->ic_trailer;
                /* NB: frags always have any TKIP MIC done in s/w */
                if ((k->wk_flags & IEEE80211_KEY_SWMIC) == 0 && !isfrag)
                        pktlen += cip->ic_miclen;
                keyix = k->wk_keyix;

                /* packet header may have moved, reset our local pointer */
                wh = mtod(m0, struct ieee80211_frame *);
        } else if (ni->ni_ucastkey.wk_cipher == &ieee80211_cipher_none) {
                /*
                 * Use station key cache slot, if assigned.
                 */
                keyix = ni->ni_ucastkey.wk_keyix;
                if (keyix == IEEE80211_KEYIX_NONE)
                        keyix = HAL_TXKEYIX_INVALID;
        } else
                keyix = HAL_TXKEYIX_INVALID;

        pktlen += IEEE80211_CRC_LEN;

        /*
         * Load the DMA map so any coalescing is done.  This
         * also calculates the number of descriptors we need.
         */
        error = ath_tx_dmasetup(sc, bf, m0);
        if (error != 0) {
                return error;
        }
        bf->bf_node = ni;                       /* NB: held reference */
        m0 = bf->bf_m;                          /* NB: may have changed */
        wh = mtod(m0, struct ieee80211_frame *);

        /* setup descriptors */
        ds = bf->bf_desc;
        rt = sc->sc_currates;
        KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));

        /*
         * NB: the 802.11 layer marks whether or not we should
         * use short preamble based on the current mode and
         * negotiated parameters.
         */
        if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
            (ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE)) {
                shortPreamble = AH_TRUE;
                sc->sc_stats.ast_tx_shortpre++;
        } else {
                shortPreamble = AH_FALSE;
        }

        an = ATH_NODE(ni);
        flags = HAL_TXDESC_CLRDMASK;            /* XXX needed for crypto errs */
        ismrr = 0;                              /* default no multi-rate retry*/
        pri = M_WME_GETAC(m0);                  /* honor classification */
        /* XXX use txparams instead of fixed values */
        /*
         * Calculate Atheros packet type from IEEE80211 packet header,
         * setup for rate calculations, and select h/w transmit queue.
         */
        switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
        case IEEE80211_FC0_TYPE_MGT:
                subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
                if (subtype == IEEE80211_FC0_SUBTYPE_BEACON)
                        atype = HAL_PKT_TYPE_BEACON;
                else if (subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
                        atype = HAL_PKT_TYPE_PROBE_RESP;
                else if (subtype == IEEE80211_FC0_SUBTYPE_ATIM)
                        atype = HAL_PKT_TYPE_ATIM;
                else
                        atype = HAL_PKT_TYPE_NORMAL;    /* XXX */
                rix = an->an_mgmtrix;
                txrate = rt->info[rix].rateCode;
                if (shortPreamble)
                        txrate |= rt->info[rix].shortPreamble;
                try0 = ATH_TXMGTTRY;
                flags |= HAL_TXDESC_INTREQ;     /* force interrupt */
                break;
        case IEEE80211_FC0_TYPE_CTL:
                atype = HAL_PKT_TYPE_PSPOLL;    /* stop setting of duration */
                rix = an->an_mgmtrix;
                txrate = rt->info[rix].rateCode;
                if (shortPreamble)
                        txrate |= rt->info[rix].shortPreamble;
                try0 = ATH_TXMGTTRY;
                flags |= HAL_TXDESC_INTREQ;     /* force interrupt */
                break;
        case IEEE80211_FC0_TYPE_DATA:
                atype = HAL_PKT_TYPE_NORMAL;            /* default */
                /*
                 * Data frames: multicast frames go out at a fixed rate,
                 * EAPOL frames use the mgmt frame rate; otherwise consult
                 * the rate control module for the rate to use.
                 */
                if (ismcast) {
                        rix = an->an_mcastrix;
                        txrate = rt->info[rix].rateCode;
                        if (shortPreamble)
                                txrate |= rt->info[rix].shortPreamble;
                        try0 = 1;
                } else if (m0->m_flags & M_EAPOL) {
                        /* XXX? maybe always use long preamble? */
                        rix = an->an_mgmtrix;
                        txrate = rt->info[rix].rateCode;
                        if (shortPreamble)
                                txrate |= rt->info[rix].shortPreamble;
                        try0 = ATH_TXMAXTRY;    /* XXX?too many? */
                } else {
                        ath_rate_findrate(sc, an, shortPreamble, pktlen,
                                &rix, &try0, &txrate);
                        sc->sc_txrix = rix;             /* for LED blinking */
                        sc->sc_lastdatarix = rix;       /* for fast frames */
                        if (try0 != ATH_TXMAXTRY)
                                ismrr = 1;
                }
                if (cap->cap_wmeParams[pri].wmep_noackPolicy)
                        flags |= HAL_TXDESC_NOACK;
                break;
        default:
                if_printf(ifp, "bogus frame type 0x%x (%s)\n",
                        wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK, __func__);
                /* XXX statistic */
                ath_freetx(m0);
                return EIO;
        }
        txq = sc->sc_ac2q[pri];

        /*
         * When servicing one or more stations in power-save mode
         * (or) if there is some mcast data waiting on the mcast
         * queue (to prevent out of order delivery) multicast
         * frames must be buffered until after the beacon.
         */
        if (ismcast && (vap->iv_ps_sta || avp->av_mcastq.axq_depth))
                txq = &avp->av_mcastq;

        /*
         * Calculate miscellaneous flags.
         */
        if (ismcast) {
                flags |= HAL_TXDESC_NOACK;      /* no ack on broad/multicast */
        } else if (pktlen > vap->iv_rtsthreshold &&
            (ni->ni_ath_flags & IEEE80211_NODE_FF) == 0) {
                flags |= HAL_TXDESC_RTSENA;     /* RTS based on frame length */
                cix = rt->info[rix].controlRate;
                sc->sc_stats.ast_tx_rts++;
        }
        if (flags & HAL_TXDESC_NOACK)           /* NB: avoid double counting */
                sc->sc_stats.ast_tx_noack++;
#ifdef IEEE80211_SUPPORT_TDMA
        if (sc->sc_tdma && (flags & HAL_TXDESC_NOACK) == 0) {
                DPRINTF(sc, ATH_DEBUG_TDMA,
                    "%s: discard frame, ACK required w/ TDMA\n", __func__);
                sc->sc_stats.ast_tdma_ack++;
                ath_freetx(m0);
                return EIO;
        }
#endif

        /*
         * If 802.11g protection is enabled, determine whether
         * to use RTS/CTS or just CTS.  Note that this is only
         * done for OFDM unicast frames.
         */
        if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
            rt->info[rix].phy == IEEE80211_T_OFDM &&
            (flags & HAL_TXDESC_NOACK) == 0) {
                /* XXX fragments must use CCK rates w/ protection */
                if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
                        flags |= HAL_TXDESC_RTSENA;
                else if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
                        flags |= HAL_TXDESC_CTSENA;
                if (isfrag) {
                        /*
                         * For frags it would be desirable to use the
                         * highest CCK rate for RTS/CTS.  But stations
                         * farther away may detect it at a lower CCK rate
                         * so use the configured protection rate instead
                         * (for now).
                         */
                        cix = rt->info[sc->sc_protrix].controlRate;
                } else
                        cix = rt->info[sc->sc_protrix].controlRate;
                sc->sc_stats.ast_tx_protect++;
        }

        /*
         * Calculate duration.  This logically belongs in the 802.11
         * layer but it lacks sufficient information to calculate it.
         */
        if ((flags & HAL_TXDESC_NOACK) == 0 &&
            (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL) {
                u_int16_t dur;
                if (shortPreamble)
                        dur = rt->info[rix].spAckDuration;
                else
                        dur = rt->info[rix].lpAckDuration;
                if (wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG) {
                        dur += dur;             /* additional SIFS+ACK */
                        KASSERT(m0->m_nextpkt != NULL, ("no fragment"));
                        /*
                         * Include the size of next fragment so NAV is
                         * updated properly.  The last fragment uses only
                         * the ACK duration
                         */
                        dur += ath_hal_computetxtime(ah, rt,
                                        m0->m_nextpkt->m_pkthdr.len,
                                        rix, shortPreamble);
                }
                if (isfrag) {
                        /*
                         * Force hardware to use computed duration for next
                         * fragment by disabling multi-rate retry which updates
                         * duration based on the multi-rate duration table.
                         */
                        ismrr = 0;
                        try0 = ATH_TXMGTTRY;    /* XXX? */
                }
                *(u_int16_t *)wh->i_dur = htole16(dur);
        }

        /*
         * Calculate RTS/CTS rate and duration if needed.
         */
        ctsduration = 0;
        if (flags & (HAL_TXDESC_RTSENA|HAL_TXDESC_CTSENA)) {
                /*
                 * CTS transmit rate is derived from the transmit rate
                 * by looking in the h/w rate table.  We must also factor
                 * in whether or not a short preamble is to be used.
                 */
                /* NB: cix is set above where RTS/CTS is enabled */
                KASSERT(cix != 0xff, ("cix not setup"));
                ctsrate = rt->info[cix].rateCode;
                /*
                 * Compute the transmit duration based on the frame
                 * size and the size of an ACK frame.  We call into the
                 * HAL to do the computation since it depends on the
                 * characteristics of the actual PHY being used.
                 *
                 * NB: CTS is assumed the same size as an ACK so we can
                 *     use the precalculated ACK durations.
                 */
                if (shortPreamble) {
                        ctsrate |= rt->info[cix].shortPreamble;
                        if (flags & HAL_TXDESC_RTSENA)          /* SIFS + CTS */
                                ctsduration += rt->info[cix].spAckDuration;
                        ctsduration += ath_hal_computetxtime(ah,
                                rt, pktlen, rix, AH_TRUE);
                        if ((flags & HAL_TXDESC_NOACK) == 0)    /* SIFS + ACK */
                                ctsduration += rt->info[rix].spAckDuration;
                } else {
                        if (flags & HAL_TXDESC_RTSENA)          /* SIFS + CTS */
                                ctsduration += rt->info[cix].lpAckDuration;
                        ctsduration += ath_hal_computetxtime(ah,
                                rt, pktlen, rix, AH_FALSE);
                        if ((flags & HAL_TXDESC_NOACK) == 0)    /* SIFS + ACK */
                                ctsduration += rt->info[rix].lpAckDuration;
                }
                /*
                 * Must disable multi-rate retry when using RTS/CTS.
                 */
                ismrr = 0;
                try0 = ATH_TXMGTTRY;            /* XXX */
        } else
                ctsrate = 0;

        /*
         * At this point we are committed to sending the frame
         * and we don't need to look at m_nextpkt; clear it in
         * case this frame is part of frag chain.
         */
        m0->m_nextpkt = NULL;

        if (IFF_DUMPPKTS(sc, ATH_DEBUG_XMIT))
                ieee80211_dump_pkt(ic, mtod(m0, const uint8_t *), m0->m_len,
                    sc->sc_hwmap[rix].ieeerate, -1);

        if (ieee80211_radiotap_active_vap(vap)) {
                u_int64_t tsf = ath_hal_gettsf64(ah);

                sc->sc_tx_th.wt_tsf = htole64(tsf);
                sc->sc_tx_th.wt_flags = sc->sc_hwmap[rix].txflags;
                if (iswep)
                        sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_WEP;
                if (isfrag)
                        sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_FRAG;
                sc->sc_tx_th.wt_rate = sc->sc_hwmap[rix].ieeerate;
                sc->sc_tx_th.wt_txpower = ni->ni_txpower;
                sc->sc_tx_th.wt_antenna = sc->sc_txantenna;

                ieee80211_radiotap_tx(vap, m0);
        }

        /*
         * Determine if a tx interrupt should be generated for
         * this descriptor.  We take a tx interrupt to reap
         * descriptors when the h/w hits an EOL condition or
         * when the descriptor is specifically marked to generate
         * an interrupt.  We periodically mark descriptors in this
         * way to insure timely replenishing of the supply needed
         * for sending frames.  Defering interrupts reduces system
         * load and potentially allows more concurrent work to be
         * done but if done to aggressively can cause senders to
         * backup.
         *
         * NB: use >= to deal with sc_txintrperiod changing
         *     dynamically through sysctl.
         */
        if (flags & HAL_TXDESC_INTREQ) {
                txq->axq_intrcnt = 0;
        } else if (++txq->axq_intrcnt >= sc->sc_txintrperiod) {
                flags |= HAL_TXDESC_INTREQ;
                txq->axq_intrcnt = 0;
        }

        /*
         * Formulate first tx descriptor with tx controls.
         */
        /* XXX check return value? */
        ath_hal_setuptxdesc(ah, ds
                , pktlen                /* packet length */
                , hdrlen                /* header length */
                , atype                 /* Atheros packet type */
                , ni->ni_txpower        /* txpower */
                , txrate, try0          /* series 0 rate/tries */
                , keyix                 /* key cache index */
                , sc->sc_txantenna      /* antenna mode */
                , flags                 /* flags */
                , ctsrate               /* rts/cts rate */
                , ctsduration           /* rts/cts duration */
        );
        bf->bf_txflags = flags;
        /*
         * Setup the multi-rate retry state only when we're
         * going to use it.  This assumes ath_hal_setuptxdesc
         * initializes the descriptors (so we don't have to)
         * when the hardware supports multi-rate retry and
         * we don't use it.
         */
        if (ismrr)
                ath_rate_setupxtxdesc(sc, an, ds, shortPreamble, rix);

        ath_tx_handoff(sc, txq, bf);
        return 0;
}

/*
 * Process completed xmit descriptors from the specified queue.
 */
static int
ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
{
        struct ath_hal *ah = sc->sc_ah;
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_buf *bf, *last;
        struct ath_desc *ds, *ds0;
        struct ath_tx_status *ts;
        struct ieee80211_node *ni;
        struct ath_node *an;
        int sr, lr, pri, nacked;
        HAL_STATUS status;

        DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: tx queue %u head %p link %p\n",
                __func__, txq->axq_qnum,
                (caddr_t)(uintptr_t) ath_hal_gettxbuf(sc->sc_ah, txq->axq_qnum),
                txq->axq_link);
        nacked = 0;
        for (;;) {
                int qbusy;

                txq->axq_intrcnt = 0;   /* reset periodic desc intr count */
                bf = STAILQ_FIRST(&txq->axq_q);
                if (bf == NULL)
                        break;
                ds0 = &bf->bf_desc[0];
                ds = &bf->bf_desc[bf->bf_nseg - 1];
                ts = &bf->bf_status.ds_txstat;
                qbusy = ath_hal_txqenabled(ah, txq->axq_qnum);
                status = ath_hal_txprocdesc(ah, ds, ts);
#ifdef ATH_DEBUG
                if (sc->sc_debug & ATH_DEBUG_XMIT_DESC)
                        ath_printtxbuf(sc, bf, txq->axq_qnum, 0,
                            status == HAL_OK);
#endif
                if (status == HAL_EINPROGRESS) {
#ifdef IEEE80211_SUPPORT_TDMA
                        /*
                         * If not done and the queue is not busy then the
                         * transmitter raced the hardware on the link field
                         * and we have to restart it.
                         */
                        if (!qbusy) {
                                cpu_sfence();
                                ath_hal_puttxbuf(ah, txq->axq_qnum,
                                                 bf->bf_daddr);
                                ath_hal_txstart(ah, txq->axq_qnum);
                        }
#endif
                        break;
                }
                ATH_TXQ_REMOVE_HEAD(txq, bf_list);
#ifdef IEEE80211_SUPPORT_TDMA
                if (txq->axq_depth > 0) {
                        /*
                         * More frames follow.  Mark the buffer busy
                         * so it's not re-used while the hardware may
                         * still re-read the link field in the descriptor.
                         */
                        bf->bf_flags |= ATH_BUF_BUSY;
                } else
#else
                if (txq->axq_depth == 0)
#endif
                        txq->axq_link = NULL;

                ni = bf->bf_node;
                if (ni != NULL) {
                        an = ATH_NODE(ni);
                        if (ts->ts_status == 0) {
                                u_int8_t txant = ts->ts_antenna;
                                sc->sc_stats.ast_ant_tx[txant]++;
                                sc->sc_ant_tx[txant]++;
                                if (ts->ts_finaltsi != 0)
                                        sc->sc_stats.ast_tx_altrate++;
                                pri = M_WME_GETAC(bf->bf_m);
                                if (pri >= WME_AC_VO)
                                        ic->ic_wme.wme_hipri_traffic++;
                                if ((bf->bf_txflags & HAL_TXDESC_NOACK) == 0)
                                        ni->ni_inact = ni->ni_inact_reload;
                        } else {
                                if (ts->ts_status & HAL_TXERR_XRETRY)
                                        sc->sc_stats.ast_tx_xretries++;
                                if (ts->ts_status & HAL_TXERR_FIFO)
                                        sc->sc_stats.ast_tx_fifoerr++;
                                if (ts->ts_status & HAL_TXERR_FILT)
                                        sc->sc_stats.ast_tx_filtered++;
                                if (bf->bf_m->m_flags & M_FF)
                                        sc->sc_stats.ast_ff_txerr++;
                        }
                        sr = ts->ts_shortretry;
                        lr = ts->ts_longretry;
                        sc->sc_stats.ast_tx_shortretry += sr;
                        sc->sc_stats.ast_tx_longretry += lr;
                        /*
                         * Hand the descriptor to the rate control algorithm.
                         */
                        if ((ts->ts_status & HAL_TXERR_FILT) == 0 &&
                            (bf->bf_txflags & HAL_TXDESC_NOACK) == 0) {
                                /*
                                 * If frame was ack'd update statistics,
                                 * including the last rx time used to
                                 * workaround phantom bmiss interrupts.
                                 */
                                if (ts->ts_status == 0) {
                                        nacked++;
                                        sc->sc_stats.ast_tx_rssi = ts->ts_rssi;
                                        ATH_RSSI_LPF(sc->sc_halstats.ns_avgtxrssi,
                                                ts->ts_rssi);
                                }
                                ath_rate_tx_complete(sc, an, bf);
                        }
                        /*
                         * Do any tx complete callback.  Note this must
                         * be done before releasing the node reference.
                         */
                        if (bf->bf_m->m_flags & M_TXCB)
                                ieee80211_process_callback(ni, bf->bf_m,
                                    (bf->bf_txflags & HAL_TXDESC_NOACK) == 0 ?
                                        ts->ts_status : HAL_TXERR_XRETRY);
                        ieee80211_free_node(ni);
                }
                bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
                    BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);

                m_freem(bf->bf_m);
                bf->bf_m = NULL;
                bf->bf_node = NULL;

                last = STAILQ_LAST(&sc->sc_txbuf, ath_buf, bf_list);
                if (last != NULL)
                        last->bf_flags &= ~ATH_BUF_BUSY;
                STAILQ_INSERT_TAIL(&sc->sc_txbuf, bf, bf_list);
        }
#ifdef IEEE80211_SUPPORT_SUPERG
        /*
         * Flush fast-frame staging queue when traffic slows.
         */
        if (txq->axq_depth <= 1)
                ieee80211_ff_flush(ic, txq->axq_ac);
#endif
        return nacked;
}

static __inline int
txqactive(struct ath_hal *ah, int qnum)
{
        u_int32_t txqs = 1<<qnum;
        ath_hal_gettxintrtxqs(ah, &txqs);
        return (txqs & (1<<qnum));
}

/*
 * Deferred processing of transmit interrupt; special-cased
 * for a single hardware transmit queue (e.g. 5210 and 5211).
 */
static void
ath_tx_task_q0(void *arg, int npending)
{
        struct ath_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ifp;

        wlan_serialize_enter();
        if (txqactive(sc->sc_ah, 0) && ath_tx_processq(sc, &sc->sc_txq[0]))
                sc->sc_lastrx = ath_hal_gettsf64(sc->sc_ah);
        if (txqactive(sc->sc_ah, sc->sc_cabq->axq_qnum))
                ath_tx_processq(sc, sc->sc_cabq);
        ifp->if_flags &= ~IFF_OACTIVE;
        sc->sc_wd_timer = 0;

        if (sc->sc_softled)
                ath_led_event(sc, sc->sc_txrix);

        ath_start(ifp);
        wlan_serialize_exit();
}

/*
 * Deferred processing of transmit interrupt; special-cased
 * for four hardware queues, 0-3 (e.g. 5212 w/ WME support).
 */
static void
ath_tx_task_q0123(void *arg, int npending)
{
        struct ath_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ifp;
        int nacked;

        wlan_serialize_enter();
        /*
         * Process each active queue.
         */
        nacked = 0;
        if (txqactive(sc->sc_ah, 0))
                nacked += ath_tx_processq(sc, &sc->sc_txq[0]);
        if (txqactive(sc->sc_ah, 1))
                nacked += ath_tx_processq(sc, &sc->sc_txq[1]);
        if (txqactive(sc->sc_ah, 2))
                nacked += ath_tx_processq(sc, &sc->sc_txq[2]);
        if (txqactive(sc->sc_ah, 3))
                nacked += ath_tx_processq(sc, &sc->sc_txq[3]);
        if (txqactive(sc->sc_ah, sc->sc_cabq->axq_qnum))
                ath_tx_processq(sc, sc->sc_cabq);
        if (nacked)
                sc->sc_lastrx = ath_hal_gettsf64(sc->sc_ah);

        ifp->if_flags &= ~IFF_OACTIVE;
        sc->sc_wd_timer = 0;

        if (sc->sc_softled)
                ath_led_event(sc, sc->sc_txrix);

        ath_start(ifp);
        wlan_serialize_exit();
}

/*
 * Deferred processing of transmit interrupt.
 */
static void
ath_tx_task(void *arg, int npending)
{
        struct ath_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ifp;
        int i, nacked;

        wlan_serialize_enter();

        /*
         * Process each active queue.
         */
        nacked = 0;
        for (i = 0; i < HAL_NUM_TX_QUEUES; i++) {
                if (ATH_TXQ_SETUP(sc, i) && txqactive(sc->sc_ah, i))
                        nacked += ath_tx_processq(sc, &sc->sc_txq[i]);
        }
        if (nacked)
                sc->sc_lastrx = ath_hal_gettsf64(sc->sc_ah);

        ifp->if_flags &= ~IFF_OACTIVE;
        sc->sc_wd_timer = 0;

        if (sc->sc_softled)
                ath_led_event(sc, sc->sc_txrix);

        ath_start(ifp);
        wlan_serialize_exit();
}

static void
ath_tx_draintxq(struct ath_softc *sc, struct ath_txq *txq)
{
#ifdef ATH_DEBUG
        struct ath_hal *ah = sc->sc_ah;
#endif
        struct ieee80211_node *ni;
        struct ath_buf *bf;
        u_int ix;

        /*
         * NB: this assumes output has been stopped and
         *     we do not need to block ath_tx_proc
         */
        bf = STAILQ_LAST(&sc->sc_txbuf, ath_buf, bf_list);
        if (bf != NULL)
                bf->bf_flags &= ~ATH_BUF_BUSY;
        for (ix = 0;; ix++) {
                bf = STAILQ_FIRST(&txq->axq_q);
                if (bf == NULL) {
                        txq->axq_link = NULL;
                        break;
                }
                ATH_TXQ_REMOVE_HEAD(txq, bf_list);
#ifdef ATH_DEBUG
                if (sc->sc_debug & ATH_DEBUG_RESET) {
                        struct ieee80211com *ic = sc->sc_ifp->if_l2com;

                        ath_printtxbuf(sc, bf, txq->axq_qnum, ix,
                                ath_hal_txprocdesc(ah, bf->bf_desc,
                                    &bf->bf_status.ds_txstat) == HAL_OK);
                        ieee80211_dump_pkt(ic, mtod(bf->bf_m, const uint8_t *),
                            bf->bf_m->m_len, 0, -1);
                }
#endif /* ATH_DEBUG */
                bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
                ni = bf->bf_node;
                bf->bf_node = NULL;
                if (ni != NULL) {
                        /*
                         * Do any callback and reclaim the node reference.
                         */
                        if (bf->bf_m->m_flags & M_TXCB)
                                ieee80211_process_callback(ni, bf->bf_m, -1);
                        ieee80211_free_node(ni);
                }
                m_freem(bf->bf_m);
                bf->bf_m = NULL;
                bf->bf_flags &= ~ATH_BUF_BUSY;

                STAILQ_INSERT_TAIL(&sc->sc_txbuf, bf, bf_list);
        }
}

static void
ath_tx_stopdma(struct ath_softc *sc, struct ath_txq *txq)
{
        struct ath_hal *ah = sc->sc_ah;

        DPRINTF(sc, ATH_DEBUG_RESET, "%s: tx queue [%u] %p, link %p\n",
            __func__, txq->axq_qnum,
            (caddr_t)(uintptr_t) ath_hal_gettxbuf(ah, txq->axq_qnum),
            txq->axq_link);
        (void) ath_hal_stoptxdma(ah, txq->axq_qnum);
}

/*
 * Drain the transmit queues and reclaim resources.
 */
static void
ath_draintxq(struct ath_softc *sc)
{
        struct ath_hal *ah = sc->sc_ah;
        struct ifnet *ifp = sc->sc_ifp;
        int i;

        /* XXX return value */
        if (!sc->sc_invalid) {
                /* don't touch the hardware if marked invalid */
                DPRINTF(sc, ATH_DEBUG_RESET, "%s: tx queue [%u] %p, link %p\n",
                    __func__, sc->sc_bhalq,
                    (caddr_t)(uintptr_t) ath_hal_gettxbuf(ah, sc->sc_bhalq),
                    NULL);
                (void) ath_hal_stoptxdma(ah, sc->sc_bhalq);
                for (i = 0; i < HAL_NUM_TX_QUEUES; i++)
                        if (ATH_TXQ_SETUP(sc, i))
                                ath_tx_stopdma(sc, &sc->sc_txq[i]);
        }
        for (i = 0; i < HAL_NUM_TX_QUEUES; i++)
                if (ATH_TXQ_SETUP(sc, i))
                        ath_tx_draintxq(sc, &sc->sc_txq[i]);
#ifdef ATH_DEBUG
        if (sc->sc_debug & ATH_DEBUG_RESET) {
                struct ath_buf *bf = STAILQ_FIRST(&sc->sc_bbuf);
                if (bf != NULL && bf->bf_m != NULL) {
                        ath_printtxbuf(sc, bf, sc->sc_bhalq, 0,
                                ath_hal_txprocdesc(ah, bf->bf_desc,
                                    &bf->bf_status.ds_txstat) == HAL_OK);
                        ieee80211_dump_pkt(ifp->if_l2com,
                            mtod(bf->bf_m, const uint8_t *), bf->bf_m->m_len,
                            0, -1);
                }
        }
#endif /* ATH_DEBUG */
        ifp->if_flags &= ~IFF_OACTIVE;
        sc->sc_wd_timer = 0;
}

/*
 * Disable the receive h/w in preparation for a reset.
 */
static void
ath_stoprecv(struct ath_softc *sc)
{
#define PA2DESC(_sc, _pa) \
        ((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
                ((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
        struct ath_hal *ah = sc->sc_ah;

        ath_hal_stoppcurecv(ah);        /* disable PCU */
        ath_hal_setrxfilter(ah, 0);     /* clear recv filter */
        ath_hal_stopdmarecv(ah);        /* disable DMA engine */
        DELAY(3000);                    /* 3ms is long enough for 1 frame */
#ifdef ATH_DEBUG
        if (sc->sc_debug & (ATH_DEBUG_RESET | ATH_DEBUG_FATAL)) {
                struct ath_buf *bf;
                u_int ix;

                kprintf("%s: rx queue %p, link %p\n", __func__,
                        (caddr_t)(uintptr_t) ath_hal_getrxbuf(ah), sc->sc_rxlink);
                ix = 0;
                STAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
                        struct ath_desc *ds = bf->bf_desc;
                        struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
                        HAL_STATUS status = ath_hal_rxprocdesc(ah, ds,
                                bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
                        if (status == HAL_OK || (sc->sc_debug & ATH_DEBUG_FATAL))
                                ath_printrxbuf(sc, bf, ix, status == HAL_OK);
                        ix++;
                }
        }
#endif
        if (sc->sc_rxpending != NULL) {
                m_freem(sc->sc_rxpending);
                sc->sc_rxpending = NULL;
        }
        sc->sc_rxlink = NULL;           /* just in case */
#undef PA2DESC
}

/*
 * Enable the receive h/w following a reset.
 */
static int
ath_startrecv(struct ath_softc *sc)
{
        struct ath_hal *ah = sc->sc_ah;
        struct ath_buf *bf;

        sc->sc_rxlink = NULL;
        sc->sc_rxpending = NULL;
        STAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
                int error = ath_rxbuf_init(sc, bf);
                if (error != 0) {
                        DPRINTF(sc, ATH_DEBUG_RECV,
                                "%s: ath_rxbuf_init failed %d\n",
                                __func__, error);
                        return error;
                }
        }

        bf = STAILQ_FIRST(&sc->sc_rxbuf);
        ath_hal_putrxbuf(ah, bf->bf_daddr);
        ath_hal_rxena(ah);              /* enable recv descriptors */
        ath_mode_init(sc);              /* set filters, etc. */
        ath_hal_startpcurecv(ah);       /* re-enable PCU/DMA engine */
        return 0;
}

/* 
 * Update internal state after a channel change.
 */
static void
ath_chan_change(struct ath_softc *sc, struct ieee80211_channel *chan)
{
        enum ieee80211_phymode mode;

        /*
         * Change channels and update the h/w rate map
         * if we're switching; e.g. 11a to 11b/g.
         */
        mode = ieee80211_chan2mode(chan);
        if (mode != sc->sc_curmode)
                ath_setcurmode(sc, mode);
        sc->sc_curchan = chan;
}

/*
 * Set/change channels.  If the channel is really being changed,
 * it's done by reseting the chip.  To accomplish this we must
 * first cleanup any pending DMA, then restart stuff after a la
 * ath_init.
 */
static int
ath_chan_set(struct ath_softc *sc, struct ieee80211_channel *chan)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;

        DPRINTF(sc, ATH_DEBUG_RESET, "%s: %u (%u MHz, flags 0x%x)\n",
            __func__, ieee80211_chan2ieee(ic, chan),
            chan->ic_freq, chan->ic_flags);
        if (chan != sc->sc_curchan) {
                HAL_STATUS status;
                /*
                 * To switch channels clear any pending DMA operations;
                 * wait long enough for the RX fifo to drain, reset the
                 * hardware at the new frequency, and then re-enable
                 * the relevant bits of the h/w.
                 */
                ath_hal_intrset(ah, 0);         /* disable interrupts */
                ath_draintxq(sc);               /* clear pending tx frames */
                ath_stoprecv(sc);               /* turn off frame recv */
                if (!ath_hal_reset(ah, sc->sc_opmode, chan, AH_TRUE, &status)) {
                        if_printf(ifp, "%s: unable to reset "
                            "channel %u (%u MHz, flags 0x%x), hal status %u\n",
                            __func__, ieee80211_chan2ieee(ic, chan),
                            chan->ic_freq, chan->ic_flags, status);
                        return EIO;
                }
                sc->sc_diversity = ath_hal_getdiversity(ah);

                /*
                 * Re-enable rx framework.
                 */
                if (ath_startrecv(sc) != 0) {
                        if_printf(ifp, "%s: unable to restart recv logic\n",
                            __func__);
                        return EIO;
                }

                /*
                 * Change channels and update the h/w rate map
                 * if we're switching; e.g. 11a to 11b/g.
                 */
                ath_chan_change(sc, chan);

                /*
                 * Re-enable interrupts.
                 */
                ath_hal_intrset(ah, sc->sc_imask);
        }
        return 0;
}

/*
 * Periodically recalibrate the PHY to account
 * for temperature/environment changes.
 */
static void
ath_calibrate_callout(void *arg)
{
        struct ath_softc *sc = arg;
        struct ath_hal *ah = sc->sc_ah;
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        HAL_BOOL longCal, isCalDone;
        int nextcal;

        wlan_serialize_enter();

        if (ic->ic_flags & IEEE80211_F_SCAN)    /* defer, off channel */
                goto restart;
        longCal = (ticks - sc->sc_lastlongcal >= ath_longcalinterval*hz);
        if (longCal) {
                sc->sc_stats.ast_per_cal++;
                sc->sc_lastlongcal = ticks;
                if (ath_hal_getrfgain(ah) == HAL_RFGAIN_NEED_CHANGE) {
                        /*
                         * Rfgain is out of bounds, reset the chip
                         * to load new gain values.
                         */
                        DPRINTF(sc, ATH_DEBUG_CALIBRATE,
                                "%s: rfgain change\n", __func__);
                        sc->sc_stats.ast_per_rfgain++;
                        ath_reset(ifp);
                }
                /*
                 * If this long cal is after an idle period, then
                 * reset the data collection state so we start fresh.
                 */
                if (sc->sc_resetcal) {
                        (void) ath_hal_calreset(ah, sc->sc_curchan);
                        sc->sc_lastcalreset = ticks;
                        sc->sc_resetcal = 0;
                }
        }
        if (ath_hal_calibrateN(ah, sc->sc_curchan, longCal, &isCalDone)) {
                if (longCal) {
                        /*
                         * Calibrate noise floor data again in case of change.
                         */
                        ath_hal_process_noisefloor(ah);
                }
        } else {
                DPRINTF(sc, ATH_DEBUG_ANY,
                        "%s: calibration of channel %u failed\n",
                        __func__, sc->sc_curchan->ic_freq);
                sc->sc_stats.ast_per_calfail++;
        }
        if (!isCalDone) {
restart:
                /*
                 * Use a shorter interval to potentially collect multiple
                 * data samples required to complete calibration.  Once
                 * we're told the work is done we drop back to a longer
                 * interval between requests.  We're more aggressive doing
                 * work when operating as an AP to improve operation right
                 * after startup.
                 */
                nextcal = (1000*ath_shortcalinterval)/hz;
                if (sc->sc_opmode != HAL_M_HOSTAP)
                        nextcal *= 10;
        } else {
                nextcal = ath_longcalinterval*hz;
                if (sc->sc_lastcalreset == 0)
                        sc->sc_lastcalreset = sc->sc_lastlongcal;
                else if (ticks - sc->sc_lastcalreset >= ath_resetcalinterval*hz)
                        sc->sc_resetcal = 1;    /* setup reset next trip */
        }

        if (nextcal != 0) {
                DPRINTF(sc, ATH_DEBUG_CALIBRATE, "%s: next +%u (%sisCalDone)\n",
                    __func__, nextcal, isCalDone ? "" : "!");
                callout_reset(&sc->sc_cal_ch, nextcal,
                              ath_calibrate_callout, sc);
        } else {
                DPRINTF(sc, ATH_DEBUG_CALIBRATE, "%s: calibration disabled\n",
                    __func__);
                /* NB: don't rearm timer */
        }
        wlan_serialize_exit();
}

static void
ath_scan_start(struct ieee80211com *ic)
{
        struct ifnet *ifp = ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;
        u_int32_t rfilt;

        /* XXX calibration timer? */

        sc->sc_scanning = 1;
        sc->sc_syncbeacon = 0;
        rfilt = ath_calcrxfilter(sc);
        ath_hal_setrxfilter(ah, rfilt);
        ath_hal_setassocid(ah, ifp->if_broadcastaddr, 0);

        DPRINTF(sc, ATH_DEBUG_STATE, "%s: RX filter 0x%x bssid %6D aid 0\n",
                 __func__, rfilt, ifp->if_broadcastaddr, ":");
}

static void
ath_scan_end(struct ieee80211com *ic)
{
        struct ifnet *ifp = ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;
        u_int32_t rfilt;

        sc->sc_scanning = 0;
        rfilt = ath_calcrxfilter(sc);
        ath_hal_setrxfilter(ah, rfilt);
        ath_hal_setassocid(ah, sc->sc_curbssid, sc->sc_curaid);

        ath_hal_process_noisefloor(ah);

        DPRINTF(sc, ATH_DEBUG_STATE, "%s: RX filter 0x%x bssid %6D aid 0x%x\n",
                 __func__, rfilt, sc->sc_curbssid, ":",
                 sc->sc_curaid);
}

static void
ath_set_channel(struct ieee80211com *ic)
{
        struct ifnet *ifp = ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;

        (void) ath_chan_set(sc, ic->ic_curchan);
        /*
         * If we are returning to our bss channel then mark state
         * so the next recv'd beacon's tsf will be used to sync the
         * beacon timers.  Note that since we only hear beacons in
         * sta/ibss mode this has no effect in other operating modes.
         */
        if (!sc->sc_scanning && ic->ic_curchan == ic->ic_bsschan)
                sc->sc_syncbeacon = 1;
}

/* 
 * Walk the vap list and check if there any vap's in RUN state.
 */
static int
ath_isanyrunningvaps(struct ieee80211vap *this)
{
        struct ieee80211com *ic = this->iv_ic;
        struct ieee80211vap *vap;

        TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
                if (vap != this && vap->iv_state >= IEEE80211_S_RUN)
                        return 1;
        }
        return 0;
}

static int
ath_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
{
        struct ieee80211com *ic = vap->iv_ic;
        struct ath_softc *sc = ic->ic_ifp->if_softc;
        struct ath_vap *avp = ATH_VAP(vap);
        struct ath_hal *ah = sc->sc_ah;
        struct ieee80211_node *ni = NULL;
        int i, error, stamode;
        u_int32_t rfilt;
        static const HAL_LED_STATE leds[] = {
            HAL_LED_INIT,       /* IEEE80211_S_INIT */
            HAL_LED_SCAN,       /* IEEE80211_S_SCAN */
            HAL_LED_AUTH,       /* IEEE80211_S_AUTH */
            HAL_LED_ASSOC,      /* IEEE80211_S_ASSOC */
            HAL_LED_RUN,        /* IEEE80211_S_CAC */
            HAL_LED_RUN,        /* IEEE80211_S_RUN */
            HAL_LED_RUN,        /* IEEE80211_S_CSA */
            HAL_LED_RUN,        /* IEEE80211_S_SLEEP */
        };

        DPRINTF(sc, ATH_DEBUG_STATE, "%s: %s -> %s\n", __func__,
                ieee80211_state_name[vap->iv_state],
                ieee80211_state_name[nstate]);

        callout_stop(&sc->sc_cal_ch);
        ath_hal_setledstate(ah, leds[nstate]);  /* set LED */

        if (nstate == IEEE80211_S_SCAN) {
                /*
                 * Scanning: turn off beacon miss and don't beacon.
                 * Mark beacon state so when we reach RUN state we'll
                 * [re]setup beacons.  Unblock the task q thread so
                 * deferred interrupt processing is done.
                 */
                ath_hal_intrset(ah,
                    sc->sc_imask &~ (HAL_INT_SWBA | HAL_INT_BMISS));
                sc->sc_imask &= ~(HAL_INT_SWBA | HAL_INT_BMISS);
                sc->sc_beacons = 0;
                taskqueue_unblock(sc->sc_tq);
        }

        ni = vap->iv_bss;
        rfilt = ath_calcrxfilter(sc);
        stamode = (vap->iv_opmode == IEEE80211_M_STA ||
                   vap->iv_opmode == IEEE80211_M_AHDEMO ||
                   vap->iv_opmode == IEEE80211_M_IBSS);
        if (stamode && nstate == IEEE80211_S_RUN) {
                sc->sc_curaid = ni->ni_associd;
                IEEE80211_ADDR_COPY(sc->sc_curbssid, ni->ni_bssid);
                ath_hal_setassocid(ah, sc->sc_curbssid, sc->sc_curaid);
        }
        DPRINTF(sc, ATH_DEBUG_STATE, "%s: RX filter 0x%x bssid %6D aid 0x%x\n",
           __func__, rfilt, sc->sc_curbssid, ":", sc->sc_curaid);
        ath_hal_setrxfilter(ah, rfilt);

        /* XXX is this to restore keycache on resume? */
        if (vap->iv_opmode != IEEE80211_M_STA &&
            (vap->iv_flags & IEEE80211_F_PRIVACY)) {
                for (i = 0; i < IEEE80211_WEP_NKID; i++)
                        if (ath_hal_keyisvalid(ah, i))
                                ath_hal_keysetmac(ah, i, ni->ni_bssid);
        }

        /*
         * Invoke the parent method to do net80211 work.
         */
        error = avp->av_newstate(vap, nstate, arg);
        if (error != 0)
                goto bad;

        if (nstate == IEEE80211_S_RUN) {
                /* NB: collect bss node again, it may have changed */
                ni = vap->iv_bss;

                DPRINTF(sc, ATH_DEBUG_STATE,
                    "%s(RUN): iv_flags 0x%08x bintvl %d bssid %6D "
                    "capinfo 0x%04x chan %d\n", __func__,
                    vap->iv_flags, ni->ni_intval, ni->ni_bssid, ":",
                    ni->ni_capinfo, ieee80211_chan2ieee(ic, ic->ic_curchan));

                switch (vap->iv_opmode) {
#ifdef IEEE80211_SUPPORT_TDMA
                case IEEE80211_M_AHDEMO:
                        if ((vap->iv_caps & IEEE80211_C_TDMA) == 0)
                                break;
                        /* fall thru... */
#endif
                case IEEE80211_M_HOSTAP:
                case IEEE80211_M_IBSS:
                case IEEE80211_M_MBSS:
                        /*
                         * Allocate and setup the beacon frame.
                         *
                         * Stop any previous beacon DMA.  This may be
                         * necessary, for example, when an ibss merge
                         * causes reconfiguration; there will be a state
                         * transition from RUN->RUN that means we may
                         * be called with beacon transmission active.
                         */
                        ath_hal_stoptxdma(ah, sc->sc_bhalq);

                        error = ath_beacon_alloc(sc, ni);
                        if (error != 0)
                                goto bad;
                        /*
                         * If joining an adhoc network defer beacon timer
                         * configuration to the next beacon frame so we
                         * have a current TSF to use.  Otherwise we're
                         * starting an ibss/bss so there's no need to delay;
                         * if this is the first vap moving to RUN state, then
                         * beacon state needs to be [re]configured.
                         */
                        if (vap->iv_opmode == IEEE80211_M_IBSS &&
                            ni->ni_tstamp.tsf != 0) {
                                sc->sc_syncbeacon = 1;
                        } else if (!sc->sc_beacons) {
#ifdef IEEE80211_SUPPORT_TDMA
                                if (vap->iv_caps & IEEE80211_C_TDMA)
                                        ath_tdma_config(sc, vap);
                                else
#endif
                                        ath_beacon_config(sc, vap);
                                sc->sc_beacons = 1;
                        }
                        break;
                case IEEE80211_M_STA:
                        /*
                         * Defer beacon timer configuration to the next
                         * beacon frame so we have a current TSF to use
                         * (any TSF collected when scanning is likely old).
                         */
                        sc->sc_syncbeacon = 1;
                        break;
                case IEEE80211_M_MONITOR:
                        /*
                         * Monitor mode vaps have only INIT->RUN and RUN->RUN
                         * transitions so we must re-enable interrupts here to
                         * handle the case of a single monitor mode vap.
                         */
                        ath_hal_intrset(ah, sc->sc_imask);
                        break;
                case IEEE80211_M_WDS:
                        break;
                default:
                        break;
                }
                /*
                 * Let the hal process statistics collected during a
                 * scan so it can provide calibrated noise floor data.
                 */
                ath_hal_process_noisefloor(ah);
                /*
                 * Reset rssi stats; maybe not the best place...
                 */
                sc->sc_halstats.ns_avgbrssi = ATH_RSSI_DUMMY_MARKER;
                sc->sc_halstats.ns_avgrssi = ATH_RSSI_DUMMY_MARKER;
                sc->sc_halstats.ns_avgtxrssi = ATH_RSSI_DUMMY_MARKER;
                /*
                 * Finally, start any timers and the task q thread
                 * (in case we didn't go through SCAN state).
                 */
                if (ath_longcalinterval != 0) {
                        /* start periodic recalibration timer */
                        callout_reset(&sc->sc_cal_ch, 1,
                                      ath_calibrate_callout, sc);
                } else {
                        DPRINTF(sc, ATH_DEBUG_CALIBRATE,
                            "%s: calibration disabled\n", __func__);
                }
                taskqueue_unblock(sc->sc_tq);
        } else if (nstate == IEEE80211_S_INIT) {
                /*
                 * If there are no vaps left in RUN state then
                 * shutdown host/driver operation:
                 * o disable interrupts
                 * o disable the task queue thread
                 * o mark beacon processing as stopped
                 */
                if (!ath_isanyrunningvaps(vap)) {
                        sc->sc_imask &= ~(HAL_INT_SWBA | HAL_INT_BMISS);
                        /* disable interrupts  */
                        ath_hal_intrset(ah, sc->sc_imask &~ HAL_INT_GLOBAL);
                        taskqueue_block(sc->sc_tq);
                        sc->sc_beacons = 0;
                }
#ifdef IEEE80211_SUPPORT_TDMA
                ath_hal_setcca(ah, AH_TRUE);
#endif
        }
bad:
        return error;
}

/*
 * Allocate a key cache slot to the station so we can
 * setup a mapping from key index to node. The key cache
 * slot is needed for managing antenna state and for
 * compression when stations do not use crypto.  We do
 * it uniliaterally here; if crypto is employed this slot
 * will be reassigned.
 */
static void
ath_setup_stationkey(struct ieee80211_node *ni)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;
        ieee80211_keyix keyix, rxkeyix;

        if (!ath_key_alloc(vap, &ni->ni_ucastkey, &keyix, &rxkeyix)) {
                /*
                 * Key cache is full; we'll fall back to doing
                 * the more expensive lookup in software.  Note
                 * this also means no h/w compression.
                 */
                /* XXX msg+statistic */
        } else {
                /* XXX locking? */
                ni->ni_ucastkey.wk_keyix = keyix;
                ni->ni_ucastkey.wk_rxkeyix = rxkeyix;
                /* NB: must mark device key to get called back on delete */
                ni->ni_ucastkey.wk_flags |= IEEE80211_KEY_DEVKEY;
                IEEE80211_ADDR_COPY(ni->ni_ucastkey.wk_macaddr, ni->ni_macaddr);
                /* NB: this will create a pass-thru key entry */
                ath_keyset(sc, &ni->ni_ucastkey, vap->iv_bss);
        }
}

/*
 * Setup driver-specific state for a newly associated node.
 * Note that we're called also on a re-associate, the isnew
 * param tells us if this is the first time or not.
 */
static void
ath_newassoc(struct ieee80211_node *ni, int isnew)
{
        struct ath_node *an = ATH_NODE(ni);
        struct ieee80211vap *vap = ni->ni_vap;
        struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;
        const struct ieee80211_txparam *tp = ni->ni_txparms;

        an->an_mcastrix = ath_tx_findrix(sc, tp->mcastrate);
        an->an_mgmtrix = ath_tx_findrix(sc, tp->mgmtrate);

        ath_rate_newassoc(sc, an, isnew);
        if (isnew && 
            (vap->iv_flags & IEEE80211_F_PRIVACY) == 0 && sc->sc_hasclrkey &&
            ni->ni_ucastkey.wk_keyix == IEEE80211_KEYIX_NONE)
                ath_setup_stationkey(ni);
}

static int
ath_setregdomain(struct ieee80211com *ic, struct ieee80211_regdomain *reg,
        int nchans, struct ieee80211_channel chans[])
{
        struct ath_softc *sc = ic->ic_ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;
        HAL_STATUS status;

        DPRINTF(sc, ATH_DEBUG_REGDOMAIN,
            "%s: rd %u cc %u location %c%s\n",
            __func__, reg->regdomain, reg->country, reg->location,
            reg->ecm ? " ecm" : "");

        status = ath_hal_set_channels(ah, chans, nchans,
            reg->country, reg->regdomain);
        if (status != HAL_OK) {
                DPRINTF(sc, ATH_DEBUG_REGDOMAIN, "%s: failed, status %u\n",
                    __func__, status);
                return EINVAL;          /* XXX */
        }
        return 0;
}

static void
ath_getradiocaps(struct ieee80211com *ic,
        int maxchans, int *nchans, struct ieee80211_channel chans[])
{
        struct ath_softc *sc = ic->ic_ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;

        DPRINTF(sc, ATH_DEBUG_REGDOMAIN, "%s: use rd %u cc %d\n",
            __func__, SKU_DEBUG, CTRY_DEFAULT);

        /* XXX check return */
        (void) ath_hal_getchannels(ah, chans, maxchans, nchans,
            HAL_MODE_ALL, CTRY_DEFAULT, SKU_DEBUG, AH_TRUE);

}

static int
ath_getchannels(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        HAL_STATUS status;

        /*
         * Collect channel set based on EEPROM contents.
         */
        status = ath_hal_init_channels(ah, ic->ic_channels, IEEE80211_CHAN_MAX,
            &ic->ic_nchans, HAL_MODE_ALL, CTRY_DEFAULT, SKU_NONE, AH_TRUE);
        if (status != HAL_OK) {
                if_printf(ifp, "%s: unable to collect channel list from hal, "
                    "status %d\n", __func__, status);
                return EINVAL;
        }
        (void) ath_hal_getregdomain(ah, &sc->sc_eerd);
        ath_hal_getcountrycode(ah, &sc->sc_eecc);       /* NB: cannot fail */
        /* XXX map Atheros sku's to net80211 SKU's */
        /* XXX net80211 types too small */
        ic->ic_regdomain.regdomain = (uint16_t) sc->sc_eerd;
        ic->ic_regdomain.country = (uint16_t) sc->sc_eecc;
        ic->ic_regdomain.isocc[0] = ' ';        /* XXX don't know */
        ic->ic_regdomain.isocc[1] = ' ';

        ic->ic_regdomain.ecm = 1;
        ic->ic_regdomain.location = 'I';

        DPRINTF(sc, ATH_DEBUG_REGDOMAIN,
            "%s: eeprom rd %u cc %u (mapped rd %u cc %u) location %c%s\n",
            __func__, sc->sc_eerd, sc->sc_eecc,
            ic->ic_regdomain.regdomain, ic->ic_regdomain.country,
            ic->ic_regdomain.location, ic->ic_regdomain.ecm ? " ecm" : "");
        return 0;
}

static void
ath_led_done_callout(void *arg)
{
        struct ath_softc *sc = arg;

        wlan_serialize_enter();
        sc->sc_blinking = 0;
        wlan_serialize_exit();
}

/*
 * Turn the LED off: flip the pin and then set a timer so no
 * update will happen for the specified duration.
 */
static void
ath_led_off_callout(void *arg)
{
        struct ath_softc *sc = arg;

        wlan_serialize_enter();
        ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin, !sc->sc_ledon);
        callout_reset(&sc->sc_ledtimer, sc->sc_ledoff,
                        ath_led_done_callout, sc);
        wlan_serialize_exit();
}

/*
 * Blink the LED according to the specified on/off times.
 */
static void
ath_led_blink(struct ath_softc *sc, int on, int off)
{
        DPRINTF(sc, ATH_DEBUG_LED, "%s: on %u off %u\n", __func__, on, off);
        ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin, sc->sc_ledon);
        sc->sc_blinking = 1;
        sc->sc_ledoff = off;
        callout_reset(&sc->sc_ledtimer, on, ath_led_off_callout, sc);
}

static void
ath_led_event(struct ath_softc *sc, int rix)
{
        sc->sc_ledevent = ticks;        /* time of last event */
        if (sc->sc_blinking)            /* don't interrupt active blink */
                return;
        ath_led_blink(sc, sc->sc_hwmap[rix].ledon, sc->sc_hwmap[rix].ledoff);
}

static int
ath_rate_setup(struct ath_softc *sc, u_int mode)
{
        struct ath_hal *ah = sc->sc_ah;
        const HAL_RATE_TABLE *rt;

        switch (mode) {
        case IEEE80211_MODE_11A:
                rt = ath_hal_getratetable(ah, HAL_MODE_11A);
                break;
        case IEEE80211_MODE_HALF:
                rt = ath_hal_getratetable(ah, HAL_MODE_11A_HALF_RATE);
                break;
        case IEEE80211_MODE_QUARTER:
                rt = ath_hal_getratetable(ah, HAL_MODE_11A_QUARTER_RATE);
                break;
        case IEEE80211_MODE_11B:
                rt = ath_hal_getratetable(ah, HAL_MODE_11B);
                break;
        case IEEE80211_MODE_11G:
                rt = ath_hal_getratetable(ah, HAL_MODE_11G);
                break;
        case IEEE80211_MODE_TURBO_A:
                rt = ath_hal_getratetable(ah, HAL_MODE_108A);
                break;
        case IEEE80211_MODE_TURBO_G:
                rt = ath_hal_getratetable(ah, HAL_MODE_108G);
                break;
        case IEEE80211_MODE_STURBO_A:
                rt = ath_hal_getratetable(ah, HAL_MODE_TURBO);
                break;
        case IEEE80211_MODE_11NA:
                rt = ath_hal_getratetable(ah, HAL_MODE_11NA_HT20);
                break;
        case IEEE80211_MODE_11NG:
                rt = ath_hal_getratetable(ah, HAL_MODE_11NG_HT20);
                break;
        default:
                DPRINTF(sc, ATH_DEBUG_ANY, "%s: invalid mode %u\n",
                        __func__, mode);
                return 0;
        }
        sc->sc_rates[mode] = rt;
        return (rt != NULL);
}

static void
ath_setcurmode(struct ath_softc *sc, enum ieee80211_phymode mode)
{
        /* NB: on/off times from the Atheros NDIS driver, w/ permission */
        static const struct {
                u_int           rate;           /* tx/rx 802.11 rate */
                u_int16_t       timeOn;         /* LED on time (ms) */
                u_int16_t       timeOff;        /* LED off time (ms) */
        } blinkrates[] = {
                { 108,  40,  10 },
                {  96,  44,  11 },
                {  72,  50,  13 },
                {  48,  57,  14 },
                {  36,  67,  16 },
                {  24,  80,  20 },
                {  22, 100,  25 },
                {  18, 133,  34 },
                {  12, 160,  40 },
                {  10, 200,  50 },
                {   6, 240,  58 },
                {   4, 267,  66 },
                {   2, 400, 100 },
                {   0, 500, 130 },
                /* XXX half/quarter rates */
        };
        const HAL_RATE_TABLE *rt;
        int i, j;

        memset(sc->sc_rixmap, 0xff, sizeof(sc->sc_rixmap));
        rt = sc->sc_rates[mode];
        KASSERT(rt != NULL, ("no h/w rate set for phy mode %u", mode));
        for (i = 0; i < rt->rateCount; i++) {
                uint8_t ieeerate = rt->info[i].dot11Rate & IEEE80211_RATE_VAL;
                if (rt->info[i].phy != IEEE80211_T_HT)
                        sc->sc_rixmap[ieeerate] = i;
                else
                        sc->sc_rixmap[ieeerate | IEEE80211_RATE_MCS] = i;
        }
        memset(sc->sc_hwmap, 0, sizeof(sc->sc_hwmap));
        for (i = 0; i < NELEM(sc->sc_hwmap); i++) {
                if (i >= rt->rateCount) {
                        sc->sc_hwmap[i].ledon = (500 * hz) / 1000;
                        sc->sc_hwmap[i].ledoff = (130 * hz) / 1000;
                        continue;
                }
                sc->sc_hwmap[i].ieeerate =
                        rt->info[i].dot11Rate & IEEE80211_RATE_VAL;
                if (rt->info[i].phy == IEEE80211_T_HT)
                        sc->sc_hwmap[i].ieeerate |= IEEE80211_RATE_MCS;
                sc->sc_hwmap[i].txflags = IEEE80211_RADIOTAP_F_DATAPAD;
                if (rt->info[i].shortPreamble ||
                    rt->info[i].phy == IEEE80211_T_OFDM)
                        sc->sc_hwmap[i].txflags |= IEEE80211_RADIOTAP_F_SHORTPRE;
                sc->sc_hwmap[i].rxflags = sc->sc_hwmap[i].txflags;
                for (j = 0; j < NELEM(blinkrates)-1; j++)
                        if (blinkrates[j].rate == sc->sc_hwmap[i].ieeerate)
                                break;
                /* NB: this uses the last entry if the rate isn't found */
                /* XXX beware of overlow */
                sc->sc_hwmap[i].ledon = (blinkrates[j].timeOn * hz) / 1000;
                sc->sc_hwmap[i].ledoff = (blinkrates[j].timeOff * hz) / 1000;
        }
        sc->sc_currates = rt;
        sc->sc_curmode = mode;
        /*
         * All protection frames are transmited at 2Mb/s for
         * 11g, otherwise at 1Mb/s.
         */
        if (mode == IEEE80211_MODE_11G)
                sc->sc_protrix = ath_tx_findrix(sc, 2*2);
        else
                sc->sc_protrix = ath_tx_findrix(sc, 2*1);
        /* NB: caller is responsible for reseting rate control state */
}

#ifdef ATH_DEBUG
static void
ath_printrxbuf(struct ath_softc *sc, const struct ath_buf *bf,
        u_int ix, int done)
{
        const struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
        struct ath_hal *ah = sc->sc_ah;
        const struct ath_desc *ds;
        int i;

        for (i = 0, ds = bf->bf_desc; i < bf->bf_nseg; i++, ds++) {
                kprintf("R[%2u] (DS.V:%p DS.P:%p) L:%08x D:%08x%s\n"
                       "      %08x %08x %08x %08x\n",
                    ix, ds, (const struct ath_desc *)bf->bf_daddr + i,
                    ds->ds_link, ds->ds_data,
                    !done ? "" : (rs->rs_status == 0) ? " *" : " !",
                    ds->ds_ctl0, ds->ds_ctl1,
                    ds->ds_hw[0], ds->ds_hw[1]);
                if (ah->ah_magic == 0x20065416) {
                        kprintf("        %08x %08x %08x %08x %08x %08x %08x\n",
                            ds->ds_hw[2], ds->ds_hw[3], ds->ds_hw[4],
                            ds->ds_hw[5], ds->ds_hw[6], ds->ds_hw[7],
                            ds->ds_hw[8]);
                }
        }
}

static void
ath_printtxbuf(struct ath_softc *sc, const struct ath_buf *bf,
        u_int qnum, u_int ix, int done)
{
        const struct ath_tx_status *ts = &bf->bf_status.ds_txstat;
        struct ath_hal *ah = sc->sc_ah;
        const struct ath_desc *ds;
        int i;

        kprintf("Q%u[%3u]", qnum, ix);
        for (i = 0, ds = bf->bf_desc; i < bf->bf_nseg; i++, ds++) {
                kprintf(" (DS.V:%p DS.P:%p) L:%08x D:%08x F:04%x%s\n"
                       "        %08x %08x %08x %08x %08x %08x\n",
                    ds, (const struct ath_desc *)bf->bf_daddr + i,
                    ds->ds_link, ds->ds_data, bf->bf_txflags,
                    !done ? "" : (ts->ts_status == 0) ? " *" : " !",
                    ds->ds_ctl0, ds->ds_ctl1,
                    ds->ds_hw[0], ds->ds_hw[1], ds->ds_hw[2], ds->ds_hw[3]);
                if (ah->ah_magic == 0x20065416) {
                        kprintf("        %08x %08x %08x %08x %08x %08x %08x %08x\n",
                            ds->ds_hw[4], ds->ds_hw[5], ds->ds_hw[6],
                            ds->ds_hw[7], ds->ds_hw[8], ds->ds_hw[9],
                            ds->ds_hw[10],ds->ds_hw[11]);
                        kprintf("        %08x %08x %08x %08x %08x %08x %08x %08x\n",
                            ds->ds_hw[12],ds->ds_hw[13],ds->ds_hw[14],
                            ds->ds_hw[15],ds->ds_hw[16],ds->ds_hw[17],
                            ds->ds_hw[18], ds->ds_hw[19]);
                }
        }
}
#endif /* ATH_DEBUG */

static void
ath_watchdog_callout(void *arg)
{
        struct ath_softc *sc = arg;

        wlan_serialize_enter();
        if (sc->sc_wd_timer != 0 && --sc->sc_wd_timer == 0) {
                struct ifnet *ifp = sc->sc_ifp;
                uint32_t hangs;

                if (ath_hal_gethangstate(sc->sc_ah, 0xffff, &hangs) &&
                    hangs != 0) {
                        if_printf(ifp, "%s hang detected (0x%x)\n",
                            hangs & 0xff ? "bb" : "mac", hangs); 
                } else
                        if_printf(ifp, "device timeout\n");
                ath_reset(ifp);
                ifp->if_oerrors++;
                sc->sc_stats.ast_watchdog++;
        }
        callout_reset(&sc->sc_wd_ch, hz, ath_watchdog_callout, sc);
        wlan_serialize_exit();
}

#ifdef ATH_DIAGAPI
/*
 * Diagnostic interface to the HAL.  This is used by various
 * tools to do things like retrieve register contents for
 * debugging.  The mechanism is intentionally opaque so that
 * it can change frequently w/o concern for compatiblity.
 */
static int
ath_ioctl_diag(struct ath_softc *sc, struct ath_diag *ad)
{
        struct ath_hal *ah = sc->sc_ah;
        u_int id = ad->ad_id & ATH_DIAG_ID;
        void *indata = NULL;
        void *outdata = NULL;
        u_int32_t insize = ad->ad_in_size;
        u_int32_t outsize = ad->ad_out_size;
        int error = 0;

        if (ad->ad_id & ATH_DIAG_IN) {
                /*
                 * Copy in data.
                 */
                indata = kmalloc(insize, M_TEMP, M_INTWAIT);
                error = copyin(ad->ad_in_data, indata, insize);
                if (error)
                        goto bad;
        }
        if (ad->ad_id & ATH_DIAG_DYN) {
                /*
                 * Allocate a buffer for the results (otherwise the HAL
                 * returns a pointer to a buffer where we can read the
                 * results).  Note that we depend on the HAL leaving this
                 * pointer for us to use below in reclaiming the buffer;
                 * may want to be more defensive.
                 */
                outdata = kmalloc(outsize, M_TEMP, M_INTWAIT);
        }
        if (ath_hal_getdiagstate(ah, id, indata, insize, &outdata, &outsize)) {
                if (outsize < ad->ad_out_size)
                        ad->ad_out_size = outsize;
                if (outdata != NULL)
                        error = copyout(outdata, ad->ad_out_data,
                                        ad->ad_out_size);
        } else {
                error = EINVAL;
        }
bad:
        if ((ad->ad_id & ATH_DIAG_IN) && indata != NULL)
                kfree(indata, M_TEMP);
        if ((ad->ad_id & ATH_DIAG_DYN) && outdata != NULL)
                kfree(outdata, M_TEMP);
        return error;
}
#endif /* ATH_DIAGAPI */

static int
ath_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *ucred)
{
#define IS_RUNNING(ifp) \
        ((ifp->if_flags & IFF_UP) && (ifp->if_flags & IFF_RUNNING))
        struct ath_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ifreq *ifr = (struct ifreq *)data;
        const HAL_RATE_TABLE *rt;
        int error = 0;

        switch (cmd) {
        case SIOCSIFFLAGS:
                if (IS_RUNNING(ifp)) {
                        /*
                         * To avoid rescanning another access point,
                         * do not call ath_init() here.  Instead,
                         * only reflect promisc mode settings.
                         */
                        ath_mode_init(sc);
                } else if (ifp->if_flags & IFF_UP) {
                        /*
                         * Beware of being called during attach/detach
                         * to reset promiscuous mode.  In that case we
                         * will still be marked UP but not RUNNING.
                         * However trying to re-init the interface
                         * is the wrong thing to do as we've already
                         * torn down much of our state.  There's
                         * probably a better way to deal with this.
                         */
                        if (!sc->sc_invalid)
                                ath_init(sc);   /* XXX lose error */
                } else {
                        ath_stop_locked(ifp);
#ifdef notyet
                        /* XXX must wakeup in places like ath_vap_delete */
                        if (!sc->sc_invalid)
                                ath_hal_setpower(sc->sc_ah, HAL_PM_FULL_SLEEP);
#endif
                }
                break;
        case SIOCGIFMEDIA:
        case SIOCSIFMEDIA:
                error = ifmedia_ioctl(ifp, ifr, &ic->ic_media, cmd);
                break;
        case SIOCGATHSTATS:
                /* NB: embed these numbers to get a consistent view */
                sc->sc_stats.ast_tx_packets = ifp->if_opackets;
                sc->sc_stats.ast_rx_packets = ifp->if_ipackets;
                sc->sc_stats.ast_tx_rssi = ATH_RSSI(sc->sc_halstats.ns_avgtxrssi);
                sc->sc_stats.ast_rx_rssi = ATH_RSSI(sc->sc_halstats.ns_avgrssi);
#ifdef IEEE80211_SUPPORT_TDMA
                sc->sc_stats.ast_tdma_tsfadjp = TDMA_AVG(sc->sc_avgtsfdeltap);
                sc->sc_stats.ast_tdma_tsfadjm = TDMA_AVG(sc->sc_avgtsfdeltam);
#endif
                rt = sc->sc_currates;
                /* XXX HT rates */
                sc->sc_stats.ast_tx_rate =
                    rt->info[sc->sc_txrix].dot11Rate &~ IEEE80211_RATE_BASIC;
                return copyout(&sc->sc_stats,
                    ifr->ifr_data, sizeof (sc->sc_stats));
        case SIOCZATHSTATS:
                error = priv_check(curthread, PRIV_DRIVER);
                if (error == 0)
                        memset(&sc->sc_stats, 0, sizeof(sc->sc_stats));
                break;
#ifdef ATH_DIAGAPI
        case SIOCGATHDIAG:
                error = ath_ioctl_diag(sc, (struct ath_diag *) ifr);
                break;
#endif
        case SIOCGIFADDR:
                error = ether_ioctl(ifp, cmd, data);
                break;
        default:
                error = EINVAL;
                break;
        }
        return error;
#undef IS_RUNNING
}

static int
ath_sysctl_slottime(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int slottime;
        int error;

        wlan_serialize_enter();
        slottime = ath_hal_getslottime(sc->sc_ah);
        error = sysctl_handle_int(oidp, &slottime, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_setslottime(sc->sc_ah, slottime))
                        error = EINVAL;
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_acktimeout(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int acktimeout;
        int error;

        wlan_serialize_enter();
        acktimeout = ath_hal_getacktimeout(sc->sc_ah);
        error = sysctl_handle_int(oidp, &acktimeout, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_setacktimeout(sc->sc_ah, acktimeout))
                        error = EINVAL;
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_ctstimeout(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int ctstimeout;
        int error;

        wlan_serialize_enter();
        ctstimeout = ath_hal_getctstimeout(sc->sc_ah);
        error = sysctl_handle_int(oidp, &ctstimeout, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_setctstimeout(sc->sc_ah, ctstimeout))
                        error = EINVAL;
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_softled(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        int softled = sc->sc_softled;
        int error;

        error = sysctl_handle_int(oidp, &softled, 0, req);
        if (error || !req->newptr)
                return error;
        wlan_serialize_enter();
        softled = (softled != 0);
        if (softled != sc->sc_softled) {
                if (softled) {
                        /* NB: handle any sc_ledpin change */
                        ath_hal_gpioCfgOutput(sc->sc_ah, sc->sc_ledpin,
                            HAL_GPIO_MUX_MAC_NETWORK_LED);
                        ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin,
                                !sc->sc_ledon);
                }
                sc->sc_softled = softled;
        }
        wlan_serialize_exit();
        return 0;
}

static int
ath_sysctl_ledpin(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        int ledpin = sc->sc_ledpin;
        int error;

        error = sysctl_handle_int(oidp, &ledpin, 0, req);
        if (error || !req->newptr)
                return error;
        wlan_serialize_enter();
        if (ledpin != sc->sc_ledpin) {
                sc->sc_ledpin = ledpin;
                if (sc->sc_softled) {
                        ath_hal_gpioCfgOutput(sc->sc_ah, sc->sc_ledpin,
                            HAL_GPIO_MUX_MAC_NETWORK_LED);
                        ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin,
                                !sc->sc_ledon);
                }
        }
        wlan_serialize_exit();
        return 0;
}

static int
ath_sysctl_txantenna(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int txantenna;
        int error;

        wlan_serialize_enter();
        txantenna = ath_hal_getantennaswitch(sc->sc_ah);
        error = sysctl_handle_int(oidp, &txantenna, 0, req);

        if (!error && req->newptr) {
                /* XXX assumes 2 antenna ports */
                if (txantenna < HAL_ANT_VARIABLE ||
                    txantenna > HAL_ANT_FIXED_B) {
                        error = EINVAL;
                } else {
                        ath_hal_setantennaswitch(sc->sc_ah, txantenna);
                        /*
                         * NB: with the switch locked this isn't meaningful,
                         *     but set it anyway so things like radiotap get
                         *     consistent info in their data.
                         */
                        sc->sc_txantenna = txantenna;
                }
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_rxantenna(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int defantenna;
        int error;

        wlan_serialize_enter();
        defantenna = ath_hal_getdefantenna(sc->sc_ah);
        error = sysctl_handle_int(oidp, &defantenna, 0, req);
        if (error == 0 && req->newptr)
                ath_hal_setdefantenna(sc->sc_ah, defantenna);
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_diversity(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int diversity;
        int error;

        wlan_serialize_enter();
        diversity = ath_hal_getdiversity(sc->sc_ah);
        error = sysctl_handle_int(oidp, &diversity, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_setdiversity(sc->sc_ah, diversity))
                        error = EINVAL;
                else
                        sc->sc_diversity = diversity;
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_diag(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int32_t diag;
        int error;

        wlan_serialize_enter();
        if (!ath_hal_getdiag(sc->sc_ah, &diag)) {
                error = EINVAL;
        } else {
                error = sysctl_handle_int(oidp, &diag, 0, req);
                if (error == 0 && req->newptr) {
                        if (!ath_hal_setdiag(sc->sc_ah, diag))
                                error = EINVAL;
                }
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_tpscale(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        struct ifnet *ifp = sc->sc_ifp;
        u_int32_t scale;
        int error;

        wlan_serialize_enter();
        (void)ath_hal_gettpscale(sc->sc_ah, &scale);
        error = sysctl_handle_int(oidp, &scale, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_settpscale(sc->sc_ah, scale))
                        error = EINVAL;
                else if (ifp->if_flags & IFF_RUNNING)
                        error = ath_reset(ifp);
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_tpc(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int tpc;
        int error;

        wlan_serialize_enter();
        tpc = ath_hal_gettpc(sc->sc_ah);
        error = sysctl_handle_int(oidp, &tpc, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_settpc(sc->sc_ah, tpc))
                        error = EINVAL;
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_rfkill(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        struct ifnet *ifp;
        struct ath_hal *ah;
        u_int rfkill;
        int error;

        wlan_serialize_enter();
        ifp = sc->sc_ifp;
        ah = sc->sc_ah;
        rfkill = ath_hal_getrfkill(ah);

        error = sysctl_handle_int(oidp, &rfkill, 0, req);
        if (error == 0 && req->newptr) {
                if (rfkill != ath_hal_getrfkill(ah)) {
                        if (!ath_hal_setrfkill(ah, rfkill))
                                error = EINVAL;
                        else if (ifp->if_flags & IFF_RUNNING)
                                error = ath_reset(ifp);
                }
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_rfsilent(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int rfsilent;
        int error;

        wlan_serialize_enter();
        (void)ath_hal_getrfsilent(sc->sc_ah, &rfsilent);
        error = sysctl_handle_int(oidp, &rfsilent, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_setrfsilent(sc->sc_ah, rfsilent)) {
                        error = EINVAL;
                } else {
                        sc->sc_rfsilentpin = rfsilent & 0x1c;
                        sc->sc_rfsilentpol = (rfsilent & 0x2) != 0;
                }
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_tpack(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int32_t tpack;
        int error;

        wlan_serialize_enter();
        (void)ath_hal_gettpack(sc->sc_ah, &tpack);
        error = sysctl_handle_int(oidp, &tpack, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_settpack(sc->sc_ah, tpack))
                        error = EINVAL;
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_tpcts(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        u_int32_t tpcts;
        int error;

        wlan_serialize_enter();
        (void)ath_hal_gettpcts(sc->sc_ah, &tpcts);
        error = sysctl_handle_int(oidp, &tpcts, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_settpcts(sc->sc_ah, tpcts))
                        error = EINVAL;
        }
        wlan_serialize_exit();
        return error;
}

static int
ath_sysctl_intmit(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        int intmit, error;

        wlan_serialize_enter();
        intmit = ath_hal_getintmit(sc->sc_ah);
        error = sysctl_handle_int(oidp, &intmit, 0, req);
        if (error == 0 && req->newptr) {
                if (!ath_hal_setintmit(sc->sc_ah, intmit))
                        error = EINVAL;
        }
        wlan_serialize_exit();
        return error;
}

#ifdef IEEE80211_SUPPORT_TDMA
static int
ath_sysctl_setcca(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        int setcca, error;

        wlan_serialize_enter();
        setcca = sc->sc_setcca;
        error = sysctl_handle_int(oidp, &setcca, 0, req);
        if (error == 0 && req->newptr)
                sc->sc_setcca = (setcca != 0);
        wlan_serialize_exit();
        return error;
}
#endif /* IEEE80211_SUPPORT_TDMA */

static void
ath_sysctlattach(struct ath_softc *sc)
{
        struct sysctl_ctx_list *ctx;
        struct sysctl_oid *tree;
        struct ath_hal *ah = sc->sc_ah;

        ctx = &sc->sc_sysctl_ctx;
        tree = sc->sc_sysctl_tree;
        if (tree == NULL) {
                device_printf(sc->sc_dev, "can't add sysctl node\n");
                return;
        }

        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "countrycode", CTLFLAG_RD, &sc->sc_eecc, 0,
                "EEPROM country code");
        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "regdomain", CTLFLAG_RD, &sc->sc_eerd, 0,
                "EEPROM regdomain code");
#ifdef  ATH_DEBUG
        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "debug", CTLFLAG_RW, &sc->sc_debug, 0,
                "control debugging printfs");
#endif
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "slottime", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_slottime, "I", "802.11 slot time (us)");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "acktimeout", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_acktimeout, "I", "802.11 ACK timeout (us)");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "ctstimeout", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_ctstimeout, "I", "802.11 CTS timeout (us)");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "softled", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_softled, "I", "enable/disable software LED support");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "ledpin", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_ledpin, "I", "GPIO pin connected to LED");
        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "ledon", CTLFLAG_RW, &sc->sc_ledon, 0,
                "setting to turn LED on");
        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "ledidle", CTLFLAG_RW, &sc->sc_ledidle, 0,
                "idle time for inactivity LED (ticks)");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "txantenna", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_txantenna, "I", "antenna switch");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "rxantenna", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_rxantenna, "I", "default/rx antenna");
        if (ath_hal_hasdiversity(ah))
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "diversity", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_diversity, "I", "antenna diversity");
        sc->sc_txintrperiod = ATH_TXINTR_PERIOD;
        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "txintrperiod", CTLFLAG_RW, &sc->sc_txintrperiod, 0,
                "tx descriptor batching");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "diag", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_diag, "I", "h/w diagnostic control");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "tpscale", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                ath_sysctl_tpscale, "I", "tx power scaling");
        if (ath_hal_hastpc(ah)) {
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "tpc", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_tpc, "I", "enable/disable per-packet TPC");
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "tpack", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_tpack, "I", "tx power for ack frames");
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "tpcts", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_tpcts, "I", "tx power for cts frames");
        }
        if (ath_hal_hasrfsilent(ah)) {
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "rfsilent", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_rfsilent, "I", "h/w RF silent config");
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "rfkill", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_rfkill, "I", "enable/disable RF kill switch");
        }
        if (ath_hal_hasintmit(ah)) {
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "intmit", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_intmit, "I", "interference mitigation");
        }
        sc->sc_monpass = HAL_RXERR_DECRYPT | HAL_RXERR_MIC;
        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                "monpass", CTLFLAG_RW, &sc->sc_monpass, 0,
                "mask of error frames to pass when monitoring");
#ifdef IEEE80211_SUPPORT_TDMA
        if (ath_hal_macversion(ah) > 0x78) {
                sc->sc_tdmadbaprep = 2;
                SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "dbaprep", CTLFLAG_RW, &sc->sc_tdmadbaprep, 0,
                        "TDMA DBA preparation time");
                sc->sc_tdmaswbaprep = 10;
                SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "swbaprep", CTLFLAG_RW, &sc->sc_tdmaswbaprep, 0,
                        "TDMA SWBA preparation time");
                SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "guardtime", CTLFLAG_RW, &sc->sc_tdmaguard, 0,
                        "TDMA slot guard time");
                SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "superframe", CTLFLAG_RD, &sc->sc_tdmabintval, 0,
                        "TDMA calculated super frame");
                SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
                        "setcca", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
                        ath_sysctl_setcca, "I", "enable CCA control");
        }
#endif
}

static int
ath_tx_raw_start(struct ath_softc *sc, struct ieee80211_node *ni,
        struct ath_buf *bf, struct mbuf *m0,
        const struct ieee80211_bpf_params *params)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        struct ath_hal *ah = sc->sc_ah;
        struct ieee80211vap *vap = ni->ni_vap;
        int error, ismcast, ismrr;
        int keyix, hdrlen, pktlen, try0, txantenna;
        u_int8_t rix, cix, txrate, ctsrate, rate1, rate2, rate3;
        struct ieee80211_frame *wh;
        u_int flags, ctsduration;
        HAL_PKT_TYPE atype;
        const HAL_RATE_TABLE *rt;
        struct ath_desc *ds;
        u_int pri;

        wh = mtod(m0, struct ieee80211_frame *);
        ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
        hdrlen = ieee80211_anyhdrsize(wh);
        /*
         * Packet length must not include any
         * pad bytes; deduct them here.
         */
        /* XXX honor IEEE80211_BPF_DATAPAD */
        pktlen = m0->m_pkthdr.len - (hdrlen & 3) + IEEE80211_CRC_LEN;

        if (params->ibp_flags & IEEE80211_BPF_CRYPTO) {
                const struct ieee80211_cipher *cip;
                struct ieee80211_key *k;

                /*
                 * Construct the 802.11 header+trailer for an encrypted
                 * frame. The only reason this can fail is because of an
                 * unknown or unsupported cipher/key type.
                 */
                k = ieee80211_crypto_encap(ni, m0);
                if (k == NULL) {
                        /*
                         * This can happen when the key is yanked after the
                         * frame was queued.  Just discard the frame; the
                         * 802.11 layer counts failures and provides
                         * debugging/diagnostics.
                         */
                        ath_freetx(m0);
                        return EIO;
                }
                /*
                 * Adjust the packet + header lengths for the crypto
                 * additions and calculate the h/w key index.  When
                 * a s/w mic is done the frame will have had any mic
                 * added to it prior to entry so m0->m_pkthdr.len will
                 * account for it. Otherwise we need to add it to the
                 * packet length.
                 */
                cip = k->wk_cipher;
                hdrlen += cip->ic_header;
                pktlen += cip->ic_header + cip->ic_trailer;
                /* NB: frags always have any TKIP MIC done in s/w */
                if ((k->wk_flags & IEEE80211_KEY_SWMIC) == 0)
                        pktlen += cip->ic_miclen;
                keyix = k->wk_keyix;

                /* packet header may have moved, reset our local pointer */
                wh = mtod(m0, struct ieee80211_frame *);
        } else if (ni->ni_ucastkey.wk_cipher == &ieee80211_cipher_none) {
                /*
                 * Use station key cache slot, if assigned.
                 */
                keyix = ni->ni_ucastkey.wk_keyix;
                if (keyix == IEEE80211_KEYIX_NONE)
                        keyix = HAL_TXKEYIX_INVALID;
        } else
                keyix = HAL_TXKEYIX_INVALID;

        error = ath_tx_dmasetup(sc, bf, m0);
        if (error != 0)
                return error;
        m0 = bf->bf_m;                          /* NB: may have changed */
        wh = mtod(m0, struct ieee80211_frame *);
        bf->bf_node = ni;                       /* NB: held reference */

        flags = HAL_TXDESC_CLRDMASK;            /* XXX needed for crypto errs */
        flags |= HAL_TXDESC_INTREQ;             /* force interrupt */
        if (params->ibp_flags & IEEE80211_BPF_RTS)
                flags |= HAL_TXDESC_RTSENA;
        else if (params->ibp_flags & IEEE80211_BPF_CTS)
                flags |= HAL_TXDESC_CTSENA;
        /* XXX leave ismcast to injector? */
        if ((params->ibp_flags & IEEE80211_BPF_NOACK) || ismcast)
                flags |= HAL_TXDESC_NOACK;

        rt = sc->sc_currates;
        KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
        rix = ath_tx_findrix(sc, params->ibp_rate0);
        txrate = rt->info[rix].rateCode;
        if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
                txrate |= rt->info[rix].shortPreamble;
        sc->sc_txrix = rix;
        try0 = params->ibp_try0;
        ismrr = (params->ibp_try1 != 0);
        txantenna = params->ibp_pri >> 2;
        if (txantenna == 0)                     /* XXX? */
                txantenna = sc->sc_txantenna;
        ctsduration = 0;
        if (flags & (HAL_TXDESC_CTSENA | HAL_TXDESC_RTSENA)) {
                cix = ath_tx_findrix(sc, params->ibp_ctsrate);
                ctsrate = rt->info[cix].rateCode;
                if (params->ibp_flags & IEEE80211_BPF_SHORTPRE) {
                        ctsrate |= rt->info[cix].shortPreamble;
                        if (flags & HAL_TXDESC_RTSENA)          /* SIFS + CTS */
                                ctsduration += rt->info[cix].spAckDuration;
                        ctsduration += ath_hal_computetxtime(ah,
                                rt, pktlen, rix, AH_TRUE);
                        if ((flags & HAL_TXDESC_NOACK) == 0)    /* SIFS + ACK */
                                ctsduration += rt->info[rix].spAckDuration;
                } else {
                        if (flags & HAL_TXDESC_RTSENA)          /* SIFS + CTS */
                                ctsduration += rt->info[cix].lpAckDuration;
                        ctsduration += ath_hal_computetxtime(ah,
                                rt, pktlen, rix, AH_FALSE);
                        if ((flags & HAL_TXDESC_NOACK) == 0)    /* SIFS + ACK */
                                ctsduration += rt->info[rix].lpAckDuration;
                }
                ismrr = 0;                      /* XXX */
        } else
                ctsrate = 0;
        pri = params->ibp_pri & 3;
        /*
         * NB: we mark all packets as type PSPOLL so the h/w won't
         * set the sequence number, duration, etc.
         */
        atype = HAL_PKT_TYPE_PSPOLL;

        if (IFF_DUMPPKTS(sc, ATH_DEBUG_XMIT))
                ieee80211_dump_pkt(ic, mtod(m0, caddr_t), m0->m_len,
                    sc->sc_hwmap[rix].ieeerate, -1);
        
        if (ieee80211_radiotap_active_vap(vap)) {
                u_int64_t tsf = ath_hal_gettsf64(ah);

                sc->sc_tx_th.wt_tsf = htole64(tsf);
                sc->sc_tx_th.wt_flags = sc->sc_hwmap[rix].txflags;
                if (wh->i_fc[1] & IEEE80211_FC1_WEP)
                        sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_WEP;
                if (m0->m_flags & M_FRAG)
                        sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_FRAG;
                sc->sc_tx_th.wt_rate = sc->sc_hwmap[rix].ieeerate;
                sc->sc_tx_th.wt_txpower = ni->ni_txpower;
                sc->sc_tx_th.wt_antenna = sc->sc_txantenna;

                ieee80211_radiotap_tx(vap, m0);
        }

        /*
         * Formulate first tx descriptor with tx controls.
         */
        ds = bf->bf_desc;
        /* XXX check return value? */
        ath_hal_setuptxdesc(ah, ds
                , pktlen                /* packet length */
                , hdrlen                /* header length */
                , atype                 /* Atheros packet type */
                , params->ibp_power     /* txpower */
                , txrate, try0          /* series 0 rate/tries */
                , keyix                 /* key cache index */
                , txantenna             /* antenna mode */
                , flags                 /* flags */
                , ctsrate               /* rts/cts rate */
                , ctsduration           /* rts/cts duration */
        );
        bf->bf_txflags = flags;

        if (ismrr) {
                rix = ath_tx_findrix(sc, params->ibp_rate1);
                rate1 = rt->info[rix].rateCode;
                if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
                        rate1 |= rt->info[rix].shortPreamble;
                if (params->ibp_try2) {
                        rix = ath_tx_findrix(sc, params->ibp_rate2);
                        rate2 = rt->info[rix].rateCode;
                        if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
                                rate2 |= rt->info[rix].shortPreamble;
                } else
                        rate2 = 0;
                if (params->ibp_try3) {
                        rix = ath_tx_findrix(sc, params->ibp_rate3);
                        rate3 = rt->info[rix].rateCode;
                        if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
                                rate3 |= rt->info[rix].shortPreamble;
                } else
                        rate3 = 0;
                ath_hal_setupxtxdesc(ah, ds
                        , rate1, params->ibp_try1       /* series 1 */
                        , rate2, params->ibp_try2       /* series 2 */
                        , rate3, params->ibp_try3       /* series 3 */
                );
        }

        /* NB: no buffered multicast in power save support */
        ath_tx_handoff(sc, sc->sc_ac2q[pri], bf);
        return 0;
}

static int
ath_raw_xmit(struct ieee80211_node *ni, struct mbuf *m,
        const struct ieee80211_bpf_params *params)
{
        struct ieee80211com *ic = ni->ni_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct ath_softc *sc = ifp->if_softc;
        struct ath_buf *bf;
        int error;

        if ((ifp->if_flags & IFF_RUNNING) == 0 || sc->sc_invalid) {
                DPRINTF(sc, ATH_DEBUG_XMIT, "%s: discard frame, %s", __func__,
                    (ifp->if_flags & IFF_RUNNING) == 0 ?
                        "!running" : "invalid");
                m_freem(m);
                error = ENETDOWN;
                goto bad;
        }
        /*
         * Grab a TX buffer and associated resources.
         */
        bf = ath_getbuf(sc);
        if (bf == NULL) {
                sc->sc_stats.ast_tx_nobuf++;
                m_freem(m);
                error = ENOBUFS;
                goto bad;
        }

        if (params == NULL) {
                /*
                 * Legacy path; interpret frame contents to decide
                 * precisely how to send the frame.
                 */
                if (ath_tx_start(sc, ni, bf, m)) {
                        error = EIO;            /* XXX */
                        goto bad2;
                }
        } else {
                /*
                 * Caller supplied explicit parameters to use in
                 * sending the frame.
                 */
                if (ath_tx_raw_start(sc, ni, bf, m, params)) {
                        error = EIO;            /* XXX */
                        goto bad2;
                }
        }
        sc->sc_wd_timer = 5;
        ifp->if_opackets++;
        sc->sc_stats.ast_tx_raw++;

        return 0;
bad2:
        STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
bad:
        ifp->if_oerrors++;
        sc->sc_stats.ast_tx_raw_fail++;
        ieee80211_free_node(ni);
        return error;
}

/*
 * Announce various information on device/driver attach.
 */
static void
ath_announce(struct ath_softc *sc)
{
        struct ifnet *ifp = sc->sc_ifp;
        struct ath_hal *ah = sc->sc_ah;

        if_printf(ifp, "AR%s mac %d.%d RF%s phy %d.%d\n",
                ath_hal_mac_name(ah), ah->ah_macVersion, ah->ah_macRev,
                ath_hal_rf_name(ah), ah->ah_phyRev >> 4, ah->ah_phyRev & 0xf);
        if (bootverbose) {
                int i;
                for (i = 0; i <= WME_AC_VO; i++) {
                        struct ath_txq *txq = sc->sc_ac2q[i];
                        if_printf(ifp, "Use hw queue %u for %s traffic\n",
                                txq->axq_qnum, ieee80211_wme_acnames[i]);
                }
                if_printf(ifp, "Use hw queue %u for CAB traffic\n",
                        sc->sc_cabq->axq_qnum);
                if_printf(ifp, "Use hw queue %u for beacons\n", sc->sc_bhalq);
        }
        if (ath_rxbuf != ATH_RXBUF)
                if_printf(ifp, "using %u rx buffers\n", ath_rxbuf);
        if (ath_txbuf != ATH_TXBUF)
                if_printf(ifp, "using %u tx buffers\n", ath_txbuf);
        if (sc->sc_mcastkey && bootverbose)
                if_printf(ifp, "using multicast key search\n");
}

#ifdef IEEE80211_SUPPORT_TDMA
static __inline uint32_t
ath_hal_getnexttbtt(struct ath_hal *ah)
{
#define AR_TIMER0       0x8028
        return OS_REG_READ(ah, AR_TIMER0);
}

static __inline void
ath_hal_adjusttsf(struct ath_hal *ah, int32_t tsfdelta)
{
        /* XXX handle wrap/overflow */
        OS_REG_WRITE(ah, AR_TSF_L32, OS_REG_READ(ah, AR_TSF_L32) + tsfdelta);
}

static void
ath_tdma_settimers(struct ath_softc *sc, u_int32_t nexttbtt, u_int32_t bintval)
{
        struct ath_hal *ah = sc->sc_ah;
        HAL_BEACON_TIMERS bt;

        bt.bt_intval = bintval | HAL_BEACON_ENA;
        bt.bt_nexttbtt = nexttbtt;
        bt.bt_nextdba = (nexttbtt<<3) - sc->sc_tdmadbaprep;
        bt.bt_nextswba = (nexttbtt<<3) - sc->sc_tdmaswbaprep;
        bt.bt_nextatim = nexttbtt+1;
        ath_hal_beaconsettimers(ah, &bt);
}

/*
 * Calculate the beacon interval.  This is periodic in the
 * superframe for the bss.  We assume each station is configured
 * identically wrt transmit rate so the guard time we calculate
 * above will be the same on all stations.  Note we need to
 * factor in the xmit time because the hardware will schedule
 * a frame for transmit if the start of the frame is within
 * the burst time.  When we get hardware that properly kills
 * frames in the PCU we can reduce/eliminate the guard time.
 *
 * Roundup to 1024 is so we have 1 TU buffer in the guard time
 * to deal with the granularity of the nexttbtt timer.  11n MAC's
 * with 1us timer granularity should allow us to reduce/eliminate
 * this.
 */
static void
ath_tdma_bintvalsetup(struct ath_softc *sc,
        const struct ieee80211_tdma_state *tdma)
{
        /* copy from vap state (XXX check all vaps have same value?) */
        sc->sc_tdmaslotlen = tdma->tdma_slotlen;

        sc->sc_tdmabintval = roundup((sc->sc_tdmaslotlen+sc->sc_tdmaguard) *
                tdma->tdma_slotcnt, 1024);
        sc->sc_tdmabintval >>= 10;              /* TSF -> TU */
        if (sc->sc_tdmabintval & 1)
                sc->sc_tdmabintval++;

        if (tdma->tdma_slot == 0) {
                /*
                 * Only slot 0 beacons; other slots respond.
                 */
                sc->sc_imask |= HAL_INT_SWBA;
                sc->sc_tdmaswba = 0;            /* beacon immediately */
        } else {
                /* XXX all vaps must be slot 0 or slot !0 */
                sc->sc_imask &= ~HAL_INT_SWBA;
        }
}

/*
 * Max 802.11 overhead.  This assumes no 4-address frames and
 * the encapsulation done by ieee80211_encap (llc).  We also
 * include potential crypto overhead.
 */
#define IEEE80211_MAXOVERHEAD \
        (sizeof(struct ieee80211_qosframe) \
         + sizeof(struct llc) \
         + IEEE80211_ADDR_LEN \
         + IEEE80211_WEP_IVLEN \
         + IEEE80211_WEP_KIDLEN \
         + IEEE80211_WEP_CRCLEN \
         + IEEE80211_WEP_MICLEN \
         + IEEE80211_CRC_LEN)

/*
 * Setup initially for tdma operation.  Start the beacon
 * timers and enable SWBA if we are slot 0.  Otherwise
 * we wait for slot 0 to arrive so we can sync up before
 * starting to transmit.
 */
static void
ath_tdma_config(struct ath_softc *sc, struct ieee80211vap *vap)
{
        struct ath_hal *ah = sc->sc_ah;
        struct ifnet *ifp = sc->sc_ifp;
        struct ieee80211com *ic = ifp->if_l2com;
        const struct ieee80211_txparam *tp;
        const struct ieee80211_tdma_state *tdma = NULL;
        int rix;

        if (vap == NULL) {
                vap = TAILQ_FIRST(&ic->ic_vaps);   /* XXX */
                if (vap == NULL) {
                        if_printf(ifp, "%s: no vaps?\n", __func__);
                        return;
                }
        }
        tp = vap->iv_bss->ni_txparms;
        /*
         * Calculate the guard time for each slot.  This is the
         * time to send a maximal-size frame according to the
         * fixed/lowest transmit rate.  Note that the interface
         * mtu does not include the 802.11 overhead so we must
         * tack that on (ath_hal_computetxtime includes the
         * preamble and plcp in it's calculation).
         */
        tdma = vap->iv_tdma;
        if (tp->ucastrate != IEEE80211_FIXED_RATE_NONE)
                rix = ath_tx_findrix(sc, tp->ucastrate);
        else
                rix = ath_tx_findrix(sc, tp->mcastrate);
        /* XXX short preamble assumed */
        sc->sc_tdmaguard = ath_hal_computetxtime(ah, sc->sc_currates,
                ifp->if_mtu + IEEE80211_MAXOVERHEAD, rix, AH_TRUE);

        ath_hal_intrset(ah, 0);

        ath_beaconq_config(sc);                 /* setup h/w beacon q */
        if (sc->sc_setcca)
                ath_hal_setcca(ah, AH_FALSE);   /* disable CCA */
        ath_tdma_bintvalsetup(sc, tdma);        /* calculate beacon interval */
        ath_tdma_settimers(sc, sc->sc_tdmabintval,
                sc->sc_tdmabintval | HAL_BEACON_RESET_TSF);
        sc->sc_syncbeacon = 0;

        sc->sc_avgtsfdeltap = TDMA_DUMMY_MARKER;
        sc->sc_avgtsfdeltam = TDMA_DUMMY_MARKER;

        ath_hal_intrset(ah, sc->sc_imask);

        DPRINTF(sc, ATH_DEBUG_TDMA, "%s: slot %u len %uus cnt %u "
            "bsched %u guard %uus bintval %u TU dba prep %u\n", __func__,
            tdma->tdma_slot, tdma->tdma_slotlen, tdma->tdma_slotcnt,
            tdma->tdma_bintval, sc->sc_tdmaguard, sc->sc_tdmabintval,
            sc->sc_tdmadbaprep);
}

/*
 * Update tdma operation.  Called from the 802.11 layer
 * when a beacon is received from the TDMA station operating
 * in the slot immediately preceding us in the bss.  Use
 * the rx timestamp for the beacon frame to update our
 * beacon timers so we follow their schedule.  Note that
 * by using the rx timestamp we implicitly include the
 * propagation delay in our schedule.
 */
static void
ath_tdma_update(struct ieee80211_node *ni,
        const struct ieee80211_tdma_param *tdma, int changed)
{
#define TSF_TO_TU(_h,_l) \
        ((((u_int32_t)(_h)) << 22) | (((u_int32_t)(_l)) >> 10))
#define TU_TO_TSF(_tu)  (((u_int64_t)(_tu)) << 10)
        struct ieee80211vap *vap = ni->ni_vap;
        struct ieee80211com *ic = ni->ni_ic;
        struct ath_softc *sc = ic->ic_ifp->if_softc;
        struct ath_hal *ah = sc->sc_ah;
        const HAL_RATE_TABLE *rt = sc->sc_currates;
        u_int64_t tsf, rstamp, nextslot;
        u_int32_t txtime, nextslottu, timer0;
        int32_t tudelta, tsfdelta;
        const struct ath_rx_status *rs;
        int rix;

        sc->sc_stats.ast_tdma_update++;

        /*
         * Check for and adopt configuration changes.
         */
        if (changed != 0) {
                const struct ieee80211_tdma_state *ts = vap->iv_tdma;

                ath_tdma_bintvalsetup(sc, ts);
                if (changed & TDMA_UPDATE_SLOTLEN)
                        ath_wme_update(ic);

                DPRINTF(sc, ATH_DEBUG_TDMA,
                    "%s: adopt slot %u slotcnt %u slotlen %u us "
                    "bintval %u TU\n", __func__,
                    ts->tdma_slot, ts->tdma_slotcnt, ts->tdma_slotlen,
                    sc->sc_tdmabintval);

                /* XXX right? */
                ath_hal_intrset(ah, sc->sc_imask);
                /* NB: beacon timers programmed below */
        }

        /* extend rx timestamp to 64 bits */
        rs = sc->sc_lastrs;
        tsf = ath_hal_gettsf64(ah);
        rstamp = ath_extend_tsf(rs->rs_tstamp, tsf);
        /*
         * The rx timestamp is set by the hardware on completing
         * reception (at the point where the rx descriptor is DMA'd
         * to the host).  To find the start of our next slot we
         * must adjust this time by the time required to send
         * the packet just received.
         */
        rix = rt->rateCodeToIndex[rs->rs_rate];
        txtime = ath_hal_computetxtime(ah, rt, rs->rs_datalen, rix,
            rt->info[rix].shortPreamble);
        /* NB: << 9 is to cvt to TU and /2 */
        nextslot = (rstamp - txtime) + (sc->sc_tdmabintval << 9);
        nextslottu = TSF_TO_TU(nextslot>>32, nextslot) & HAL_BEACON_PERIOD;

        /*
         * TIMER0 is the h/w's idea of NextTBTT (in TU's).  Convert
         * to usecs and calculate the difference between what the
         * other station thinks and what we have programmed.  This
         * lets us figure how to adjust our timers to match.  The
         * adjustments are done by pulling the TSF forward and possibly
         * rewriting the beacon timers.
         */
        timer0 = ath_hal_getnexttbtt(ah);
        tsfdelta = (int32_t)((nextslot % TU_TO_TSF(HAL_BEACON_PERIOD+1)) - TU_TO_TSF(timer0));

        DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
            "tsfdelta %d avg +%d/-%d\n", tsfdelta,
            TDMA_AVG(sc->sc_avgtsfdeltap), TDMA_AVG(sc->sc_avgtsfdeltam));

        if (tsfdelta < 0) {
                TDMA_SAMPLE(sc->sc_avgtsfdeltap, 0);
                TDMA_SAMPLE(sc->sc_avgtsfdeltam, -tsfdelta);
                tsfdelta = -tsfdelta % 1024;
                nextslottu++;
        } else if (tsfdelta > 0) {
                TDMA_SAMPLE(sc->sc_avgtsfdeltap, tsfdelta);
                TDMA_SAMPLE(sc->sc_avgtsfdeltam, 0);
                tsfdelta = 1024 - (tsfdelta % 1024);
                nextslottu++;
        } else {
                TDMA_SAMPLE(sc->sc_avgtsfdeltap, 0);
                TDMA_SAMPLE(sc->sc_avgtsfdeltam, 0);
        }
        tudelta = nextslottu - timer0;

        /*
         * Copy sender's timetstamp into tdma ie so they can
         * calculate roundtrip time.  We submit a beacon frame
         * below after any timer adjustment.  The frame goes out
         * at the next TBTT so the sender can calculate the
         * roundtrip by inspecting the tdma ie in our beacon frame.
         *
         * NB: This tstamp is subtlely preserved when
         *     IEEE80211_BEACON_TDMA is marked (e.g. when the
         *     slot position changes) because ieee80211_add_tdma
         *     skips over the data.
         */
        memcpy(ATH_VAP(vap)->av_boff.bo_tdma +
                __offsetof(struct ieee80211_tdma_param, tdma_tstamp),
                &ni->ni_tstamp.data, 8);
#if 0
        DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
            "tsf %llu nextslot %llu (%d, %d) nextslottu %u timer0 %u (%d)\n",
            (unsigned long long) tsf, (unsigned long long) nextslot,
            (int)(nextslot - tsf), tsfdelta,
            nextslottu, timer0, tudelta);
#endif
        /*
         * Adjust the beacon timers only when pulling them forward
         * or when going back by less than the beacon interval.
         * Negative jumps larger than the beacon interval seem to
         * cause the timers to stop and generally cause instability.
         * This basically filters out jumps due to missed beacons.
         */
        if (tudelta != 0 && (tudelta > 0 || -tudelta < sc->sc_tdmabintval)) {
                ath_tdma_settimers(sc, nextslottu, sc->sc_tdmabintval);
                sc->sc_stats.ast_tdma_timers++;
        }
        if (tsfdelta > 0) {
                ath_hal_adjusttsf(ah, tsfdelta);
                sc->sc_stats.ast_tdma_tsf++;
        }
        ath_tdma_beacon_send(sc, vap);          /* prepare response */
#undef TU_TO_TSF
#undef TSF_TO_TU
}

/*
 * Transmit a beacon frame at SWBA.  Dynamic updates
 * to the frame contents are done as needed.
 */
static void
ath_tdma_beacon_send(struct ath_softc *sc, struct ieee80211vap *vap)
{
        struct ath_hal *ah = sc->sc_ah;
        struct ath_buf *bf;
        int otherant;

        /*
         * Check if the previous beacon has gone out.  If
         * not don't try to post another, skip this period
         * and wait for the next.  Missed beacons indicate
         * a problem and should not occur.  If we miss too
         * many consecutive beacons reset the device.
         */
        if (ath_hal_numtxpending(ah, sc->sc_bhalq) != 0) {
                sc->sc_bmisscount++;
                DPRINTF(sc, ATH_DEBUG_BEACON,
                        "%s: missed %u consecutive beacons\n",
                        __func__, sc->sc_bmisscount);
                if (sc->sc_bmisscount >= ath_bstuck_threshold)
                        taskqueue_enqueue(sc->sc_tq, &sc->sc_bstucktask);
                return;
        }
        if (sc->sc_bmisscount != 0) {
                DPRINTF(sc, ATH_DEBUG_BEACON,
                        "%s: resume beacon xmit after %u misses\n",
                        __func__, sc->sc_bmisscount);
                sc->sc_bmisscount = 0;
        }

        /*
         * Check recent per-antenna transmit statistics and flip
         * the default antenna if noticeably more frames went out
         * on the non-default antenna.
         * XXX assumes 2 anntenae
         */
        if (!sc->sc_diversity) {
                otherant = sc->sc_defant & 1 ? 2 : 1;
                if (sc->sc_ant_tx[otherant] > sc->sc_ant_tx[sc->sc_defant] + 2)
                        ath_setdefantenna(sc, otherant);
                sc->sc_ant_tx[1] = sc->sc_ant_tx[2] = 0;
        }

        /*
         * Stop any current dma before messing with the beacon linkages.
         *
         * This should never fail since we check above that no frames
         * are still pending on the queue.
         */
        if (!ath_hal_stoptxdma(ah, sc->sc_bhalq)) {
                DPRINTF(sc, ATH_DEBUG_ANY,
                        "%s: beacon queue %u did not stop?\n",
                        __func__, sc->sc_bhalq);
                /* NB: the HAL still stops DMA, so proceed */
        }
        bf = ath_beacon_generate(sc, vap);
        if (bf != NULL) {
                ath_hal_puttxbuf(ah, sc->sc_bhalq, bf->bf_daddr);
                ath_hal_txstart(ah, sc->sc_bhalq);

                sc->sc_stats.ast_be_xmit++;             /* XXX per-vap? */

                /*
                 * Record local TSF for our last send for use
                 * in arbitrating slot collisions.
                 */
                vap->iv_bss->ni_tstamp.tsf = ath_hal_gettsf64(ah);
        } else {
                device_printf(sc->sc_dev, "tdma beacon gen failed!\n");
        }
}
#endif /* IEEE80211_SUPPORT_TDMA */

static int
ath_sysctl_clearstats(SYSCTL_HANDLER_ARGS)
{
        struct ath_softc *sc = arg1;
        int val = 0;
        int error;

        error = sysctl_handle_int(oidp, &val, 0, req);
        if (error || !req->newptr)
                return error;
        if (val == 0)
                return 0;       /* Not clearing the stats is still valid */
        memset(&sc->sc_stats, 0, sizeof(sc->sc_stats));
        val = 0;
        return 0;
}

static void
ath_sysctl_stats_attach(struct ath_softc *sc)
{
        struct sysctl_oid *tree;
        struct sysctl_ctx_list *ctx;
        struct sysctl_oid_list *child;

        ctx = &sc->sc_sysctl_ctx;
        tree = sc->sc_sysctl_tree;
        child = SYSCTL_CHILDREN(tree);

        /* Create "clear" node */
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
            "clear_stats", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
            ath_sysctl_clearstats, "I", "clear stats");

        /* Create stats node */
        tree = SYSCTL_ADD_NODE(ctx, child, OID_AUTO, "stats", CTLFLAG_RD,
            NULL, "Statistics");
        child = SYSCTL_CHILDREN(tree);

        /* This was generated from if_athioctl.h */

        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_watchdog", CTLFLAG_RD,
            &sc->sc_stats.ast_watchdog, 0, "device reset by watchdog");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_hardware", CTLFLAG_RD,
            &sc->sc_stats.ast_hardware, 0, "fatal hardware error interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_bmiss", CTLFLAG_RD,
            &sc->sc_stats.ast_bmiss, 0, "beacon miss interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_bmiss_phantom", CTLFLAG_RD,
            &sc->sc_stats.ast_bmiss_phantom, 0, "beacon miss interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_bstuck", CTLFLAG_RD,
            &sc->sc_stats.ast_bstuck, 0, "beacon stuck interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rxorn", CTLFLAG_RD,
            &sc->sc_stats.ast_rxorn, 0, "rx overrun interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rxeol", CTLFLAG_RD,
            &sc->sc_stats.ast_rxeol, 0, "rx eol interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_txurn", CTLFLAG_RD,
            &sc->sc_stats.ast_txurn, 0, "tx underrun interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_mib", CTLFLAG_RD,
            &sc->sc_stats.ast_mib, 0, "mib interrupts");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_intrcoal", CTLFLAG_RD,
            &sc->sc_stats.ast_intrcoal, 0, "interrupts coalesced");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_packets", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_packets, 0, "packet sent on the interface");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_mgmt", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_mgmt, 0, "management frames transmitted");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_discard", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_discard, 0, "frames discarded prior to assoc");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_qstop", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_qstop, 0, "output stopped 'cuz no buffer");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_encap", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_encap, 0, "tx encapsulation failed");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_nonode", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_nonode, 0, "tx failed 'cuz no node");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_nombuf", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_nombuf, 0, "tx failed 'cuz no mbuf");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_nomcl", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_nomcl, 0, "tx failed 'cuz no cluster");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_linear", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_linear, 0, "tx linearized to cluster");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_nodata", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_nodata, 0, "tx discarded empty frame");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_busdma", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_busdma, 0, "tx failed for dma resrcs");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_xretries", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_xretries, 0, "tx failed 'cuz too many retries");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_fifoerr", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_fifoerr, 0, "tx failed 'cuz FIFO underrun");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_filtered", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_filtered, 0, "tx failed 'cuz xmit filtered");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_shortretry", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_shortretry, 0, "tx on-chip retries (short)");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_longretry", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_longretry, 0, "tx on-chip retries (long)");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_badrate", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_badrate, 0, "tx failed 'cuz bogus xmit rate");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_noack", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_noack, 0, "tx frames with no ack marked");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_rts", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_rts, 0, "tx frames with rts enabled");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_cts", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_cts, 0, "tx frames with cts enabled");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_shortpre", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_shortpre, 0, "tx frames with short preamble");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_altrate", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_altrate, 0, "tx frames with alternate rate");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_protect", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_protect, 0, "tx frames with protection");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_ctsburst", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_ctsburst, 0, "tx frames with cts and bursting");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_ctsext", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_ctsext, 0, "tx frames with cts extension");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_nombuf", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_nombuf, 0, "rx setup failed 'cuz no mbuf");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_busdma", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_busdma, 0, "rx setup failed for dma resrcs");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_orn", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_orn, 0, "rx failed 'cuz of desc overrun");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_crcerr", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_crcerr, 0, "rx failed 'cuz of bad CRC");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_fifoerr", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_fifoerr, 0, "rx failed 'cuz of FIFO overrun");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_badcrypt", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_badcrypt, 0, "rx failed 'cuz decryption");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_badmic", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_badmic, 0, "rx failed 'cuz MIC failure");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_phyerr", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_phyerr, 0, "rx failed 'cuz of PHY err");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_tooshort", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_tooshort, 0, "rx discarded 'cuz frame too short");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_toobig", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_toobig, 0, "rx discarded 'cuz frame too large");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_packets", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_packets, 0, "packet recv on the interface");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_mgt", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_mgt, 0, "management frames received");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rx_ctl", CTLFLAG_RD,
            &sc->sc_stats.ast_rx_ctl, 0, "rx discarded 'cuz ctl frame");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_be_xmit", CTLFLAG_RD,
            &sc->sc_stats.ast_be_xmit, 0, "beacons transmitted");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_be_nombuf", CTLFLAG_RD,
            &sc->sc_stats.ast_be_nombuf, 0, "beacon setup failed 'cuz no mbuf");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_per_cal", CTLFLAG_RD,
            &sc->sc_stats.ast_per_cal, 0, "periodic calibration calls");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_per_calfail", CTLFLAG_RD,
            &sc->sc_stats.ast_per_calfail, 0, "periodic calibration failed");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_per_rfgain", CTLFLAG_RD,
            &sc->sc_stats.ast_per_rfgain, 0, "periodic calibration rfgain reset");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rate_calls", CTLFLAG_RD,
            &sc->sc_stats.ast_rate_calls, 0, "rate control checks");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rate_raise", CTLFLAG_RD,
            &sc->sc_stats.ast_rate_raise, 0, "rate control raised xmit rate");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_rate_drop", CTLFLAG_RD,
            &sc->sc_stats.ast_rate_drop, 0, "rate control dropped xmit rate");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_ant_defswitch", CTLFLAG_RD,
            &sc->sc_stats.ast_ant_defswitch, 0, "rx/default antenna switches");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_ant_txswitch", CTLFLAG_RD,
            &sc->sc_stats.ast_ant_txswitch, 0, "tx antenna switches");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_cabq_xmit", CTLFLAG_RD,
            &sc->sc_stats.ast_cabq_xmit, 0, "cabq frames transmitted");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_cabq_busy", CTLFLAG_RD,
            &sc->sc_stats.ast_cabq_busy, 0, "cabq found busy");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_raw", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_raw, 0, "tx frames through raw api");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_ff_txok", CTLFLAG_RD,
            &sc->sc_stats.ast_ff_txok, 0, "fast frames tx'd successfully");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_ff_txerr", CTLFLAG_RD,
            &sc->sc_stats.ast_ff_txerr, 0, "fast frames tx'd w/ error");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_ff_rx", CTLFLAG_RD,
            &sc->sc_stats.ast_ff_rx, 0, "fast frames rx'd");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_ff_flush", CTLFLAG_RD,
            &sc->sc_stats.ast_ff_flush, 0, "fast frames flushed from staging q");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_qfull", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_qfull, 0, "tx dropped 'cuz of queue limit");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_nobuf", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_nobuf, 0, "tx dropped 'cuz no ath buffer");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tdma_update", CTLFLAG_RD,
            &sc->sc_stats.ast_tdma_update, 0, "TDMA slot timing updates");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tdma_timers", CTLFLAG_RD,
            &sc->sc_stats.ast_tdma_timers, 0, "TDMA slot update set beacon timers");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tdma_tsf", CTLFLAG_RD,
            &sc->sc_stats.ast_tdma_tsf, 0, "TDMA slot update set TSF");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tdma_ack", CTLFLAG_RD,
            &sc->sc_stats.ast_tdma_ack, 0, "TDMA tx failed 'cuz ACK required");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_raw_fail", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_raw_fail, 0, "raw tx failed 'cuz h/w down");
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_tx_nofrag", CTLFLAG_RD,
            &sc->sc_stats.ast_tx_nofrag, 0, "tx dropped 'cuz no ath frag buffer");
#if 0
        SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "ast_be_missed", CTLFLAG_RD,
            &sc->sc_stats.ast_be_missed, 0, "number of -missed- beacons");
#endif
}