Reduce ifnet.if_serializer contention on output path:

[dragonfly.git] / sys / dev / netif / ti / if_ti.c

/*
 * Copyright (c) 1997, 1998, 1999
 *      Bill Paul <wpaul@ctr.columbia.edu>.  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.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Bill Paul.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 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 DAMAGE.
 *
 * $FreeBSD: src/sys/pci/if_ti.c,v 1.25.2.14 2002/02/15 04:20:20 silby Exp $
 * $DragonFly: src/sys/dev/netif/ti/if_ti.c,v 1.51 2008/05/14 11:59:22 sephe Exp $
 */

/*
 * Alteon Networks Tigon PCI gigabit ethernet driver for FreeBSD.
 * Manuals, sample driver and firmware source kits are available
 * from http://www.alteon.com/support/openkits.
 * 
 * Written by Bill Paul <wpaul@ctr.columbia.edu>
 * Electrical Engineering Department
 * Columbia University, New York City
 */

/*
 * The Alteon Networks Tigon chip contains an embedded R4000 CPU,
 * gigabit MAC, dual DMA channels and a PCI interface unit. NICs
 * using the Tigon may have anywhere from 512K to 2MB of SRAM. The
 * Tigon supports hardware IP, TCP and UCP checksumming, multicast
 * filtering and jumbo (9014 byte) frames. The hardware is largely
 * controlled by firmware, which must be loaded into the NIC during
 * initialization.
 *
 * The Tigon 2 contains 2 R4000 CPUs and requires a newer firmware
 * revision, which supports new features such as extended commands,
 * extended jumbo receive ring desciptors and a mini receive ring.
 *
 * Alteon Networks is to be commended for releasing such a vast amount
 * of development material for the Tigon NIC without requiring an NDA
 * (although they really should have done it a long time ago). With
 * any luck, the other vendors will finally wise up and follow Alteon's
 * stellar example.
 *
 * The firmware for the Tigon 1 and 2 NICs is compiled directly into
 * this driver by #including it as a C header file. This bloats the
 * driver somewhat, but it's the easiest method considering that the
 * driver code and firmware code need to be kept in sync. The source
 * for the firmware is not provided with the FreeBSD distribution since
 * compiling it requires a GNU toolchain targeted for mips-sgi-irix5.3.
 *
 * The following people deserve special thanks:
 * - Terry Murphy of 3Com, for providing a 3c985 Tigon 1 board
 *   for testing
 * - Raymond Lee of Netgear, for providing a pair of Netgear
 *   GA620 Tigon 2 boards for testing
 * - Ulf Zimmermann, for bringing the GA260 to my attention and
 *   convincing me to write this driver.
 * - Andrew Gallatin for providing FreeBSD/Alpha support.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/queue.h>
#include <sys/serialize.h>
#include <sys/bus.h>
#include <sys/rman.h>
#include <sys/thread2.h>
#include <sys/interrupt.h>

#include <net/if.h>
#include <net/ifq_var.h>
#include <net/if_arp.h>
#include <net/ethernet.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/vlan/if_vlan_var.h>
#include <net/vlan/if_vlan_ether.h>

#include <net/bpf.h>

#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip.h>

#include <vm/vm.h>              /* for vtophys */
#include <vm/pmap.h>            /* for vtophys */

#include <bus/pci/pcireg.h>
#include <bus/pci/pcivar.h>

#include "if_tireg.h"
#include "ti_fw.h"
#include "ti_fw2.h"

/*
 * Temporarily disable the checksum offload support for now.
 * Tests with ftp.freesoftware.com show that after about 12 hours,
 * the firmware will begin calculating completely bogus TX checksums
 * and refuse to stop until the interface is reset. Unfortunately,
 * there isn't enough time to fully debug this before the 4.1
 * release, so this will need to stay off for now.
 */
#ifdef notdef
#define TI_CSUM_FEATURES        (CSUM_IP | CSUM_TCP | CSUM_UDP | CSUM_IP_FRAGS)
#else
#define TI_CSUM_FEATURES        0
#endif

/*
 * Various supported device vendors/types and their names.
 */

static struct ti_type ti_devs[] = {
        { ALT_VENDORID, ALT_DEVICEID_ACENIC,
                "Alteon AceNIC 1000baseSX Gigabit Ethernet" },
        { ALT_VENDORID, ALT_DEVICEID_ACENIC_COPPER,
                "Alteon AceNIC 1000baseT Gigabit Ethernet" },
        { TC_VENDORID,  TC_DEVICEID_3C985,
                "3Com 3c985-SX Gigabit Ethernet" },
        { NG_VENDORID, NG_DEVICEID_GA620,
                "Netgear GA620 1000baseSX Gigabit Ethernet" },
        { NG_VENDORID, NG_DEVICEID_GA620T,
                "Netgear GA620 1000baseT Gigabit Ethernet" },
        { SGI_VENDORID, SGI_DEVICEID_TIGON,
                "Silicon Graphics Gigabit Ethernet" },
        { DEC_VENDORID, DEC_DEVICEID_FARALLON_PN9000SX,
                "Farallon PN9000SX Gigabit Ethernet" },
        { 0, 0, NULL }
};

static int      ti_probe(device_t);
static int      ti_attach(device_t);
static int      ti_detach(device_t);
static void     ti_txeof(struct ti_softc *);
static void     ti_rxeof(struct ti_softc *);

static void     ti_stats_update(struct ti_softc *);
static int      ti_encap(struct ti_softc *, struct mbuf *, uint32_t *);

static void     ti_intr(void *);
static void     ti_start(struct ifnet *);
static int      ti_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
static void     ti_init(void *);
static void     ti_init2(struct ti_softc *);
static void     ti_stop(struct ti_softc *);
static void     ti_watchdog(struct ifnet *);
static void     ti_shutdown(device_t);
static int      ti_ifmedia_upd(struct ifnet *);
static void     ti_ifmedia_sts(struct ifnet *, struct ifmediareq *);

static uint32_t ti_eeprom_putbyte(struct ti_softc *, int);
static uint8_t  ti_eeprom_getbyte(struct ti_softc *, int, uint8_t *);
static int      ti_read_eeprom(struct ti_softc *, caddr_t, int, int);

static void     ti_add_mcast(struct ti_softc *, struct ether_addr *);
static void     ti_del_mcast(struct ti_softc *, struct ether_addr *);
static void     ti_setmulti(struct ti_softc *);

static void     ti_mem(struct ti_softc *, uint32_t, uint32_t, caddr_t);
static void     ti_loadfw(struct ti_softc *);
static void     ti_cmd(struct ti_softc *, struct ti_cmd_desc *);
static void     ti_cmd_ext(struct ti_softc *, struct ti_cmd_desc *,
                           caddr_t, int);
static void     ti_handle_events(struct ti_softc *);
static int      ti_alloc_jumbo_mem(struct ti_softc *);
static struct ti_jslot *
                ti_jalloc(struct ti_softc *);
static void     ti_jfree(void *);
static void     ti_jref(void *);
static int      ti_newbuf_std(struct ti_softc *, int, struct mbuf *);
static int      ti_newbuf_mini(struct ti_softc *, int, struct mbuf *);
static int      ti_newbuf_jumbo(struct ti_softc *, int, struct mbuf *);
static int      ti_init_rx_ring_std(struct ti_softc *);
static void     ti_free_rx_ring_std(struct ti_softc *);
static int      ti_init_rx_ring_jumbo(struct ti_softc *);
static void     ti_free_rx_ring_jumbo(struct ti_softc *);
static int      ti_init_rx_ring_mini(struct ti_softc *);
static void     ti_free_rx_ring_mini(struct ti_softc *);
static void     ti_free_tx_ring(struct ti_softc *);
static int      ti_init_tx_ring(struct ti_softc *);

static int      ti_64bitslot_war(struct ti_softc *);
static int      ti_chipinit(struct ti_softc *);
static int      ti_gibinit(struct ti_softc *);

static device_method_t ti_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         ti_probe),
        DEVMETHOD(device_attach,        ti_attach),
        DEVMETHOD(device_detach,        ti_detach),
        DEVMETHOD(device_shutdown,      ti_shutdown),
        { 0, 0 }
};


static DEFINE_CLASS_0(ti, ti_driver, ti_methods, sizeof(struct ti_softc));
static devclass_t ti_devclass;

DECLARE_DUMMY_MODULE(if_ti);
DRIVER_MODULE(if_ti, pci, ti_driver, ti_devclass, 0, 0);

/*
 * Send an instruction or address to the EEPROM, check for ACK.
 */
static uint32_t
ti_eeprom_putbyte(struct ti_softc *sc, int byte)
{
        int ack = 0, i;

        /*
         * Make sure we're in TX mode.
         */
        TI_SETBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_TXEN);

        /*
         * Feed in each bit and stobe the clock.
         */
        for (i = 0x80; i; i >>= 1) {
                if (byte & i)
                        TI_SETBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_DOUT);
                else
                        TI_CLRBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_DOUT);
                DELAY(1);
                TI_SETBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_CLK);
                DELAY(1);
                TI_CLRBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_CLK);
        }

        /*
         * Turn off TX mode.
         */
        TI_CLRBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_TXEN);

        /*
         * Check for ack.
         */
        TI_SETBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_CLK);
        ack = CSR_READ_4(sc, TI_MISC_LOCAL_CTL) & TI_MLC_EE_DIN;
        TI_CLRBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_CLK);

        return(ack);
}

/*
 * Read a byte of data stored in the EEPROM at address 'addr.'
 * We have to send two address bytes since the EEPROM can hold
 * more than 256 bytes of data.
 */
static uint8_t
ti_eeprom_getbyte(struct ti_softc *sc, int addr, uint8_t *dest)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        int i;
        uint8_t byte = 0;

        EEPROM_START;

        /*
         * Send write control code to EEPROM.
         */
        if (ti_eeprom_putbyte(sc, EEPROM_CTL_WRITE)) {
                if_printf(ifp, "failed to send write command, status: %x\n",
                          CSR_READ_4(sc, TI_MISC_LOCAL_CTL));
                return(1);
        }

        /*
         * Send first byte of address of byte we want to read.
         */
        if (ti_eeprom_putbyte(sc, (addr >> 8) & 0xFF)) {
                if_printf(ifp, "failed to send address, status: %x\n",
                          CSR_READ_4(sc, TI_MISC_LOCAL_CTL));
                return(1);
        }
        /*
         * Send second byte address of byte we want to read.
         */
        if (ti_eeprom_putbyte(sc, addr & 0xFF)) {
                if_printf(ifp, "failed to send address, status: %x\n",
                          CSR_READ_4(sc, TI_MISC_LOCAL_CTL));
                return(1);
        }

        EEPROM_STOP;
        EEPROM_START;
        /*
         * Send read control code to EEPROM.
         */
        if (ti_eeprom_putbyte(sc, EEPROM_CTL_READ)) {
                if_printf(ifp, "failed to send read command, status: %x\n",
                          CSR_READ_4(sc, TI_MISC_LOCAL_CTL));
                return(1);
        }

        /*
         * Start reading bits from EEPROM.
         */
        TI_CLRBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_TXEN);
        for (i = 0x80; i; i >>= 1) {
                TI_SETBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_CLK);
                DELAY(1);
                if (CSR_READ_4(sc, TI_MISC_LOCAL_CTL) & TI_MLC_EE_DIN)
                        byte |= i;
                TI_CLRBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_EE_CLK);
                DELAY(1);
        }

        EEPROM_STOP;

        /*
         * No ACK generated for read, so just return byte.
         */

        *dest = byte;

        return(0);
}

/*
 * Read a sequence of bytes from the EEPROM.
 */
static int
ti_read_eeprom(struct ti_softc *sc, caddr_t dest, int off, int cnt)
{
        int err = 0, i;
        uint8_t byte = 0;

        for (i = 0; i < cnt; i++) {
                err = ti_eeprom_getbyte(sc, off + i, &byte);
                if (err)
                        break;
                *(dest + i) = byte;
        }

        return(err ? 1 : 0);
}

/*
 * NIC memory access function. Can be used to either clear a section
 * of NIC local memory or (if buf is non-NULL) copy data into it.
 */
static void
ti_mem(struct ti_softc *sc, uint32_t addr, uint32_t len, caddr_t buf)
{
        int cnt, segptr, segsize;
        caddr_t ti_winbase, ptr;

        segptr = addr;
        cnt = len;
        ti_winbase = (caddr_t)(sc->ti_vhandle + TI_WINDOW);
        ptr = buf;

        while(cnt) {
                if (cnt < TI_WINLEN)
                        segsize = cnt;
                else
                        segsize = TI_WINLEN - (segptr % TI_WINLEN);
                CSR_WRITE_4(sc, TI_WINBASE, (segptr & ~(TI_WINLEN - 1)));
                if (buf == NULL)
                        bzero((char *)ti_winbase + (segptr &
                            (TI_WINLEN - 1)), segsize);
                else {
                        bcopy((char *)ptr, (char *)ti_winbase +
                            (segptr & (TI_WINLEN - 1)), segsize);
                        ptr += segsize;
                }
                segptr += segsize;
                cnt -= segsize;
        }
}

/*
 * Load firmware image into the NIC. Check that the firmware revision
 * is acceptable and see if we want the firmware for the Tigon 1 or
 * Tigon 2.
 */
static void
ti_loadfw(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;

        switch(sc->ti_hwrev) {
        case TI_HWREV_TIGON:
                if (tigonFwReleaseMajor != TI_FIRMWARE_MAJOR ||
                    tigonFwReleaseMinor != TI_FIRMWARE_MINOR ||
                    tigonFwReleaseFix != TI_FIRMWARE_FIX) {
                        if_printf(ifp, "firmware revision mismatch; want "
                                  "%d.%d.%d, got %d.%d.%d\n",
                                  TI_FIRMWARE_MAJOR, TI_FIRMWARE_MINOR,
                                  TI_FIRMWARE_FIX, tigonFwReleaseMajor,
                                  tigonFwReleaseMinor, tigonFwReleaseFix);
                        return;
                }
                ti_mem(sc, tigonFwTextAddr, tigonFwTextLen,
                    (caddr_t)tigonFwText);
                ti_mem(sc, tigonFwDataAddr, tigonFwDataLen,
                    (caddr_t)tigonFwData);
                ti_mem(sc, tigonFwRodataAddr, tigonFwRodataLen,
                    (caddr_t)tigonFwRodata);
                ti_mem(sc, tigonFwBssAddr, tigonFwBssLen, NULL);
                ti_mem(sc, tigonFwSbssAddr, tigonFwSbssLen, NULL);
                CSR_WRITE_4(sc, TI_CPU_PROGRAM_COUNTER, tigonFwStartAddr);
                break;
        case TI_HWREV_TIGON_II:
                if (tigon2FwReleaseMajor != TI_FIRMWARE_MAJOR ||
                    tigon2FwReleaseMinor != TI_FIRMWARE_MINOR ||
                    tigon2FwReleaseFix != TI_FIRMWARE_FIX) {
                        if_printf(ifp, "firmware revision mismatch; want "
                                  "%d.%d.%d, got %d.%d.%d\n",
                                  TI_FIRMWARE_MAJOR, TI_FIRMWARE_MINOR,
                                  TI_FIRMWARE_FIX, tigon2FwReleaseMajor,
                                  tigon2FwReleaseMinor, tigon2FwReleaseFix);
                        return;
                }
                ti_mem(sc, tigon2FwTextAddr, tigon2FwTextLen,
                    (caddr_t)tigon2FwText);
                ti_mem(sc, tigon2FwDataAddr, tigon2FwDataLen,
                    (caddr_t)tigon2FwData);
                ti_mem(sc, tigon2FwRodataAddr, tigon2FwRodataLen,
                    (caddr_t)tigon2FwRodata);
                ti_mem(sc, tigon2FwBssAddr, tigon2FwBssLen, NULL);
                ti_mem(sc, tigon2FwSbssAddr, tigon2FwSbssLen, NULL);
                CSR_WRITE_4(sc, TI_CPU_PROGRAM_COUNTER, tigon2FwStartAddr);
                break;
        default:
                if_printf(ifp, "can't load firmware: unknown hardware rev\n");
                break;
        }
}

/*
 * Send the NIC a command via the command ring.
 */
static void
ti_cmd(struct ti_softc *sc, struct ti_cmd_desc *cmd)
{
        uint32_t index;

        if (sc->ti_rdata->ti_cmd_ring == NULL)
                return;

        index = sc->ti_cmd_saved_prodidx;
        CSR_WRITE_4(sc, TI_GCR_CMDRING + (index * 4), *(uint32_t *)(cmd));
        TI_INC(index, TI_CMD_RING_CNT);
        CSR_WRITE_4(sc, TI_MB_CMDPROD_IDX, index);
        sc->ti_cmd_saved_prodidx = index;
}

/*
 * Send the NIC an extended command. The 'len' parameter specifies the
 * number of command slots to include after the initial command.
 */
static void
ti_cmd_ext(struct ti_softc *sc, struct ti_cmd_desc *cmd, caddr_t arg, int len)
{
        uint32_t index;
        int i;

        if (sc->ti_rdata->ti_cmd_ring == NULL)
                return;

        index = sc->ti_cmd_saved_prodidx;
        CSR_WRITE_4(sc, TI_GCR_CMDRING + (index * 4), *(uint32_t *)(cmd));
        TI_INC(index, TI_CMD_RING_CNT);
        for (i = 0; i < len; i++) {
                CSR_WRITE_4(sc, TI_GCR_CMDRING + (index * 4),
                    *(uint32_t *)(&arg[i * 4]));
                TI_INC(index, TI_CMD_RING_CNT);
        }
        CSR_WRITE_4(sc, TI_MB_CMDPROD_IDX, index);
        sc->ti_cmd_saved_prodidx = index;
}

/*
 * Handle events that have triggered interrupts.
 */
static void
ti_handle_events(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ti_event_desc *e;

        if (sc->ti_rdata->ti_event_ring == NULL)
                return;

        while (sc->ti_ev_saved_considx != sc->ti_ev_prodidx.ti_idx) {
                e = &sc->ti_rdata->ti_event_ring[sc->ti_ev_saved_considx];
                switch(e->ti_event) {
                case TI_EV_LINKSTAT_CHANGED:
                        sc->ti_linkstat = e->ti_code;
                        if (e->ti_code == TI_EV_CODE_LINK_UP) {
                                if_printf(ifp, "10/100 link up\n");
                        } else if (e->ti_code == TI_EV_CODE_GIG_LINK_UP) {
                                if_printf(ifp, "gigabit link up\n");
                        } else if (e->ti_code == TI_EV_CODE_LINK_DOWN) {
                                if_printf(ifp, "link down\n");
                        }
                        break;
                case TI_EV_ERROR:
                        if (e->ti_code == TI_EV_CODE_ERR_INVAL_CMD) {
                                if_printf(ifp, "invalid command\n");
                        } else if (e->ti_code == TI_EV_CODE_ERR_UNIMP_CMD) {
                                if_printf(ifp, "unknown command\n");
                        } else if (e->ti_code == TI_EV_CODE_ERR_BADCFG) {
                                if_printf(ifp, "bad config data\n");
                        }
                        break;
                case TI_EV_FIRMWARE_UP:
                        ti_init2(sc);
                        break;
                case TI_EV_STATS_UPDATED:
                        ti_stats_update(sc);
                        break;
                case TI_EV_RESET_JUMBO_RING:
                case TI_EV_MCAST_UPDATED:
                        /* Who cares. */
                        break;
                default:
                        if_printf(ifp, "unknown event: %d\n", e->ti_event);
                        break;
                }
                /* Advance the consumer index. */
                TI_INC(sc->ti_ev_saved_considx, TI_EVENT_RING_CNT);
                CSR_WRITE_4(sc, TI_GCR_EVENTCONS_IDX, sc->ti_ev_saved_considx);
        }
}

/*
 * Memory management for the jumbo receive ring is a pain in the
 * butt. We need to allocate at least 9018 bytes of space per frame,
 * _and_ it has to be contiguous (unless you use the extended
 * jumbo descriptor format). Using malloc() all the time won't
 * work: malloc() allocates memory in powers of two, which means we
 * would end up wasting a considerable amount of space by allocating
 * 9K chunks. We don't have a jumbo mbuf cluster pool. Thus, we have
 * to do our own memory management.
 *
 * The driver needs to allocate a contiguous chunk of memory at boot
 * time. We then chop this up ourselves into 9K pieces and use them
 * as external mbuf storage.
 *
 * One issue here is how much memory to allocate. The jumbo ring has
 * 256 slots in it, but at 9K per slot than can consume over 2MB of
 * RAM. This is a bit much, especially considering we also need
 * RAM for the standard ring and mini ring (on the Tigon 2). To
 * save space, we only actually allocate enough memory for 64 slots
 * by default, which works out to between 500 and 600K. This can
 * be tuned by changing a #define in if_tireg.h.
 */

static int
ti_alloc_jumbo_mem(struct ti_softc *sc)
{
        struct ti_jslot *entry;
        caddr_t ptr;
        int i;

        /* Grab a big chunk o' storage. */
        sc->ti_cdata.ti_jumbo_buf = contigmalloc(TI_JMEM, M_DEVBUF,
                M_WAITOK, 0, 0xffffffff, PAGE_SIZE, 0);

        if (sc->ti_cdata.ti_jumbo_buf == NULL) {
                if_printf(&sc->arpcom.ac_if, "no memory for jumbo buffers!\n");
                return(ENOBUFS);
        }

        lwkt_serialize_init(&sc->ti_jslot_serializer);
        SLIST_INIT(&sc->ti_jfree_listhead);

        /*
         * Now divide it up into 9K pieces and save the addresses
         * in an array. Note that we play an evil trick here by using
         * the first few bytes in the buffer to hold the the address
         * of the softc structure for this interface. This is because
         * ti_jfree() needs it, but it is called by the mbuf management
         * code which will not pass it to us explicitly.
         */
        ptr = sc->ti_cdata.ti_jumbo_buf;
        for (i = 0; i < TI_JSLOTS; i++) {
                entry = &sc->ti_cdata.ti_jslots[i];
                entry->ti_sc = sc;
                entry->ti_buf = ptr;
                entry->ti_inuse = 0;
                entry->ti_slot = i;
                SLIST_INSERT_HEAD(&sc->ti_jfree_listhead, entry, jslot_link);
                ptr += TI_JLEN;
        }

        return(0);
}

/*
 * Allocate a jumbo buffer.
 */
static struct ti_jslot *
ti_jalloc(struct ti_softc *sc)
{
        struct ti_jslot *entry;

        lwkt_serialize_enter(&sc->ti_jslot_serializer);
        entry = SLIST_FIRST(&sc->ti_jfree_listhead);
        if (entry) {
                SLIST_REMOVE_HEAD(&sc->ti_jfree_listhead, jslot_link);
                entry->ti_inuse = 1;
        } else {
                if_printf(&sc->arpcom.ac_if, "no free jumbo buffers\n");
        }
        lwkt_serialize_exit(&sc->ti_jslot_serializer);
        return(entry);
}

/*
 * Adjust usage count on a jumbo buffer. In general this doesn't
 * get used much because our jumbo buffers don't get passed around
 * too much, but it's implemented for correctness.
 */
static void
ti_jref(void *arg)
{
        struct ti_jslot *entry = (struct ti_jslot *)arg;
        struct ti_softc *sc = entry->ti_sc;

        if (sc == NULL)
                panic("ti_jref: can't find softc pointer!");

        if (&sc->ti_cdata.ti_jslots[entry->ti_slot] != entry)
                panic("ti_jref: asked to reference buffer "
                    "that we don't manage!");
        if (entry->ti_inuse == 0)
                panic("ti_jref: buffer already free!");
        atomic_add_int(&entry->ti_inuse, 1);
}

/*
 * Release a jumbo buffer.
 */
static void
ti_jfree(void *arg)
{
        struct ti_jslot *entry = (struct ti_jslot *)arg;
        struct ti_softc *sc = entry->ti_sc;

        if (sc == NULL)
                panic("ti_jref: can't find softc pointer!");

        if (&sc->ti_cdata.ti_jslots[entry->ti_slot] != entry)
                panic("ti_jref: asked to reference buffer "
                    "that we don't manage!");
        if (entry->ti_inuse == 0)
                panic("ti_jref: buffer already free!");
        lwkt_serialize_enter(&sc->ti_jslot_serializer);
        atomic_subtract_int(&entry->ti_inuse, 1);
        if (entry->ti_inuse == 0)
                SLIST_INSERT_HEAD(&sc->ti_jfree_listhead, entry, jslot_link);
        lwkt_serialize_exit(&sc->ti_jslot_serializer);
}


/*
 * Intialize a standard receive ring descriptor.
 */
static int
ti_newbuf_std(struct ti_softc *sc, int i, struct mbuf *m)
{
        struct mbuf *m_new;
        struct ti_rx_desc *r;

        if (m == NULL) {
                m_new = m_getcl(MB_DONTWAIT, MT_DATA, M_PKTHDR);
                if (m_new == NULL)
                        return (ENOBUFS);
                m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
        } else {
                m_new = m;
                m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
                m_new->m_data = m_new->m_ext.ext_buf;
        }


        m_adj(m_new, ETHER_ALIGN);
        sc->ti_cdata.ti_rx_std_chain[i] = m_new;
        r = &sc->ti_rdata->ti_rx_std_ring[i];
        TI_HOSTADDR(r->ti_addr) = vtophys(mtod(m_new, caddr_t));
        r->ti_type = TI_BDTYPE_RECV_BD;
        r->ti_flags = 0;
        if (sc->arpcom.ac_if.if_hwassist)
                r->ti_flags |= TI_BDFLAG_TCP_UDP_CKSUM | TI_BDFLAG_IP_CKSUM;
        r->ti_len = m_new->m_len;
        r->ti_idx = i;

        return(0);
}

/*
 * Intialize a mini receive ring descriptor. This only applies to
 * the Tigon 2.
 */
static int
ti_newbuf_mini(struct ti_softc *sc, int i, struct mbuf *m)
{
        struct mbuf *m_new;
        struct ti_rx_desc *r;

        if (m == NULL) {
                MGETHDR(m_new, MB_DONTWAIT, MT_DATA);
                if (m_new == NULL) {
                        return(ENOBUFS);
                }
                m_new->m_len = m_new->m_pkthdr.len = MHLEN;
        } else {
                m_new = m;
                m_new->m_data = m_new->m_pktdat;
                m_new->m_len = m_new->m_pkthdr.len = MHLEN;
        }

        m_adj(m_new, ETHER_ALIGN);
        r = &sc->ti_rdata->ti_rx_mini_ring[i];
        sc->ti_cdata.ti_rx_mini_chain[i] = m_new;
        TI_HOSTADDR(r->ti_addr) = vtophys(mtod(m_new, caddr_t));
        r->ti_type = TI_BDTYPE_RECV_BD;
        r->ti_flags = TI_BDFLAG_MINI_RING;
        if (sc->arpcom.ac_if.if_hwassist)
                r->ti_flags |= TI_BDFLAG_TCP_UDP_CKSUM | TI_BDFLAG_IP_CKSUM;
        r->ti_len = m_new->m_len;
        r->ti_idx = i;

        return(0);
}

/*
 * Initialize a jumbo receive ring descriptor. This allocates
 * a jumbo buffer from the pool managed internally by the driver.
 */
static int
ti_newbuf_jumbo(struct ti_softc *sc, int i, struct mbuf *m)
{
        struct mbuf *m_new;
        struct ti_rx_desc *r;
        struct ti_jslot *buf;

        if (m == NULL) {
                /* Allocate the mbuf. */
                MGETHDR(m_new, MB_DONTWAIT, MT_DATA);
                if (m_new == NULL) {
                        return(ENOBUFS);
                }

                /* Allocate the jumbo buffer */
                buf = ti_jalloc(sc);
                if (buf == NULL) {
                        m_freem(m_new);
                        if_printf(&sc->arpcom.ac_if, "jumbo allocation failed "
                                  "-- packet dropped!\n");
                        return(ENOBUFS);
                }

                /* Attach the buffer to the mbuf. */
                m_new->m_ext.ext_arg = buf;
                m_new->m_ext.ext_buf = buf->ti_buf;
                m_new->m_ext.ext_free = ti_jfree;
                m_new->m_ext.ext_ref = ti_jref;
                m_new->m_ext.ext_size = TI_JUMBO_FRAMELEN;

                m_new->m_flags |= M_EXT;
        } else {
                /*
                 * We're re-using a previously allocated mbuf;
                 * be sure to re-init pointers and lengths to
                 * default values.
                 */
                KKASSERT(m->m_flags & M_EXT);
                m_new = m;
        }
        m_new->m_data = m_new->m_ext.ext_buf;
        m_new->m_len = m_new->m_pkthdr.len = m_new->m_ext.ext_size;

        m_adj(m_new, ETHER_ALIGN);
        /* Set up the descriptor. */
        r = &sc->ti_rdata->ti_rx_jumbo_ring[i];
        sc->ti_cdata.ti_rx_jumbo_chain[i] = m_new;
        TI_HOSTADDR(r->ti_addr) = vtophys(mtod(m_new, caddr_t));
        r->ti_type = TI_BDTYPE_RECV_JUMBO_BD;
        r->ti_flags = TI_BDFLAG_JUMBO_RING;
        if (sc->arpcom.ac_if.if_hwassist)
                r->ti_flags |= TI_BDFLAG_TCP_UDP_CKSUM | TI_BDFLAG_IP_CKSUM;
        r->ti_len = m_new->m_len;
        r->ti_idx = i;

        return(0);
}

/*
 * The standard receive ring has 512 entries in it. At 2K per mbuf cluster,
 * that's 1MB or memory, which is a lot. For now, we fill only the first
 * 256 ring entries and hope that our CPU is fast enough to keep up with
 * the NIC.
 */
static int
ti_init_rx_ring_std(struct ti_softc *sc)
{
        int i;
        struct ti_cmd_desc cmd;

        for (i = 0; i < TI_SSLOTS; i++) {
                if (ti_newbuf_std(sc, i, NULL) == ENOBUFS)
                        return(ENOBUFS);
        };

        TI_UPDATE_STDPROD(sc, i - 1);
        sc->ti_std = i - 1;

        return(0);
}

static void
ti_free_rx_ring_std(struct ti_softc *sc)
{
        int i;

        for (i = 0; i < TI_STD_RX_RING_CNT; i++) {
                if (sc->ti_cdata.ti_rx_std_chain[i] != NULL) {
                        m_freem(sc->ti_cdata.ti_rx_std_chain[i]);
                        sc->ti_cdata.ti_rx_std_chain[i] = NULL;
                }
                bzero(&sc->ti_rdata->ti_rx_std_ring[i],
                    sizeof(struct ti_rx_desc));
        }
}

static int
ti_init_rx_ring_jumbo(struct ti_softc *sc)
{
        int i;
        struct ti_cmd_desc cmd;

        for (i = 0; i < TI_JUMBO_RX_RING_CNT; i++) {
                if (ti_newbuf_jumbo(sc, i, NULL) == ENOBUFS)
                        return(ENOBUFS);
        }

        TI_UPDATE_JUMBOPROD(sc, i - 1);
        sc->ti_jumbo = i - 1;

        return(0);
}

static void
ti_free_rx_ring_jumbo(struct ti_softc *sc)
{
        int i;

        for (i = 0; i < TI_JUMBO_RX_RING_CNT; i++) {
                if (sc->ti_cdata.ti_rx_jumbo_chain[i] != NULL) {
                        m_freem(sc->ti_cdata.ti_rx_jumbo_chain[i]);
                        sc->ti_cdata.ti_rx_jumbo_chain[i] = NULL;
                }
                bzero(&sc->ti_rdata->ti_rx_jumbo_ring[i],
                    sizeof(struct ti_rx_desc));
        }
}

static int
ti_init_rx_ring_mini(struct ti_softc *sc)
{
        int i;

        for (i = 0; i < TI_MSLOTS; i++) {
                if (ti_newbuf_mini(sc, i, NULL) == ENOBUFS)
                        return(ENOBUFS);
        }

        TI_UPDATE_MINIPROD(sc, i - 1);
        sc->ti_mini = i - 1;

        return(0);
}

static void
ti_free_rx_ring_mini(struct ti_softc *sc)
{
        int i;

        for (i = 0; i < TI_MINI_RX_RING_CNT; i++) {
                if (sc->ti_cdata.ti_rx_mini_chain[i] != NULL) {
                        m_freem(sc->ti_cdata.ti_rx_mini_chain[i]);
                        sc->ti_cdata.ti_rx_mini_chain[i] = NULL;
                }
                bzero(&sc->ti_rdata->ti_rx_mini_ring[i],
                    sizeof(struct ti_rx_desc));
        }
}

static void
ti_free_tx_ring(struct ti_softc *sc)
{
        int i;

        if (sc->ti_rdata->ti_tx_ring == NULL)
                return;

        for (i = 0; i < TI_TX_RING_CNT; i++) {
                if (sc->ti_cdata.ti_tx_chain[i] != NULL) {
                        m_freem(sc->ti_cdata.ti_tx_chain[i]);
                        sc->ti_cdata.ti_tx_chain[i] = NULL;
                }
                bzero(&sc->ti_rdata->ti_tx_ring[i],
                    sizeof(struct ti_tx_desc));
        }
}

static int
ti_init_tx_ring(struct ti_softc *sc)
{
        sc->ti_txcnt = 0;
        sc->ti_tx_saved_considx = 0;
        CSR_WRITE_4(sc, TI_MB_SENDPROD_IDX, 0);
        return(0);
}

/*
 * The Tigon 2 firmware has a new way to add/delete multicast addresses,
 * but we have to support the old way too so that Tigon 1 cards will
 * work.
 */
static void
ti_add_mcast(struct ti_softc *sc, struct ether_addr *addr)
{
        struct ti_cmd_desc cmd;
        uint16_t *m;
        uint32_t ext[2] = {0, 0};

        m = (uint16_t *)&addr->octet[0];

        switch(sc->ti_hwrev) {
        case TI_HWREV_TIGON:
                CSR_WRITE_4(sc, TI_GCR_MAR0, htons(m[0]));
                CSR_WRITE_4(sc, TI_GCR_MAR1, (htons(m[1]) << 16) | htons(m[2]));
                TI_DO_CMD(TI_CMD_ADD_MCAST_ADDR, 0, 0);
                break;
        case TI_HWREV_TIGON_II:
                ext[0] = htons(m[0]);
                ext[1] = (htons(m[1]) << 16) | htons(m[2]);
                TI_DO_CMD_EXT(TI_CMD_EXT_ADD_MCAST, 0, 0, (caddr_t)&ext, 2);
                break;
        default:
                if_printf(&sc->arpcom.ac_if, "unknown hwrev\n");
                break;
        }
}

static void
ti_del_mcast(struct ti_softc *sc, struct ether_addr *addr)
{
        struct ti_cmd_desc cmd;
        uint16_t *m;
        uint32_t ext[2] = {0, 0};

        m = (uint16_t *)&addr->octet[0];

        switch(sc->ti_hwrev) {
        case TI_HWREV_TIGON:
                CSR_WRITE_4(sc, TI_GCR_MAR0, htons(m[0]));
                CSR_WRITE_4(sc, TI_GCR_MAR1, (htons(m[1]) << 16) | htons(m[2]));
                TI_DO_CMD(TI_CMD_DEL_MCAST_ADDR, 0, 0);
                break;
        case TI_HWREV_TIGON_II:
                ext[0] = htons(m[0]);
                ext[1] = (htons(m[1]) << 16) | htons(m[2]);
                TI_DO_CMD_EXT(TI_CMD_EXT_DEL_MCAST, 0, 0, (caddr_t)&ext, 2);
                break;
        default:
                if_printf(&sc->arpcom.ac_if, "unknown hwrev\n");
                break;
        }
}

/*
 * Configure the Tigon's multicast address filter.
 *
 * The actual multicast table management is a bit of a pain, thanks to
 * slight brain damage on the part of both Alteon and us. With our
 * multicast code, we are only alerted when the multicast address table
 * changes and at that point we only have the current list of addresses:
 * we only know the current state, not the previous state, so we don't
 * actually know what addresses were removed or added. The firmware has
 * state, but we can't get our grubby mits on it, and there is no 'delete
 * all multicast addresses' command. Hence, we have to maintain our own
 * state so we know what addresses have been programmed into the NIC at
 * any given time.
 */
static void
ti_setmulti(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ifmultiaddr *ifma;
        struct ti_cmd_desc cmd;
        struct ti_mc_entry *mc;
        uint32_t intrs;

        if (ifp->if_flags & IFF_ALLMULTI) {
                TI_DO_CMD(TI_CMD_SET_ALLMULTI, TI_CMD_CODE_ALLMULTI_ENB, 0);
                return;
        }

        TI_DO_CMD(TI_CMD_SET_ALLMULTI, TI_CMD_CODE_ALLMULTI_DIS, 0);

        /* Disable interrupts. */
        intrs = CSR_READ_4(sc, TI_MB_HOSTINTR);
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, 1);

        /* First, zot all the existing filters. */
        while (sc->ti_mc_listhead.slh_first != NULL) {
                mc = sc->ti_mc_listhead.slh_first;
                ti_del_mcast(sc, &mc->mc_addr);
                SLIST_REMOVE_HEAD(&sc->ti_mc_listhead, mc_entries);
                kfree(mc, M_DEVBUF);
        }

        /* Now program new ones. */
        LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
                if (ifma->ifma_addr->sa_family != AF_LINK)
                        continue;
                mc = kmalloc(sizeof(struct ti_mc_entry), M_DEVBUF, M_INTWAIT);
                bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
                    &mc->mc_addr, ETHER_ADDR_LEN);
                SLIST_INSERT_HEAD(&sc->ti_mc_listhead, mc, mc_entries);
                ti_add_mcast(sc, &mc->mc_addr);
        }

        /* Re-enable interrupts. */
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, intrs);
}

/*
 * Check to see if the BIOS has configured us for a 64 bit slot when
 * we aren't actually in one. If we detect this condition, we can work
 * around it on the Tigon 2 by setting a bit in the PCI state register,
 * but for the Tigon 1 we must give up and abort the interface attach.
 */
static int
ti_64bitslot_war(struct ti_softc *sc)
{
        if ((CSR_READ_4(sc, TI_PCI_STATE) & TI_PCISTATE_32BIT_BUS) == 0) {
                CSR_WRITE_4(sc, 0x600, 0);
                CSR_WRITE_4(sc, 0x604, 0);
                CSR_WRITE_4(sc, 0x600, 0x5555AAAA);
                if (CSR_READ_4(sc, 0x604) == 0x5555AAAA) {
                        if (sc->ti_hwrev == TI_HWREV_TIGON)
                                return(EINVAL);
                        TI_SETBIT(sc, TI_PCI_STATE, TI_PCISTATE_32BIT_BUS);
                        return(0);
                }
        }

        return(0);
}

/*
 * Do endian, PCI and DMA initialization. Also check the on-board ROM
 * self-test results.
 */
static int
ti_chipinit(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        uint32_t cacheline;
        uint32_t pci_writemax = 0;

        /* Initialize link to down state. */
        sc->ti_linkstat = TI_EV_CODE_LINK_DOWN;

        if (ifp->if_capenable & IFCAP_HWCSUM)
                ifp->if_hwassist = TI_CSUM_FEATURES;
        else
                ifp->if_hwassist = 0;

        /* Set endianness before we access any non-PCI registers. */
#if BYTE_ORDER == BIG_ENDIAN
        CSR_WRITE_4(sc, TI_MISC_HOST_CTL,
            TI_MHC_BIGENDIAN_INIT | (TI_MHC_BIGENDIAN_INIT << 24));
#else
        CSR_WRITE_4(sc, TI_MISC_HOST_CTL,
            TI_MHC_LITTLEENDIAN_INIT | (TI_MHC_LITTLEENDIAN_INIT << 24));
#endif

        /* Check the ROM failed bit to see if self-tests passed. */
        if (CSR_READ_4(sc, TI_CPU_STATE) & TI_CPUSTATE_ROMFAIL) {
                if_printf(ifp, "board self-diagnostics failed!\n");
                return(ENODEV);
        }

        /* Halt the CPU. */
        TI_SETBIT(sc, TI_CPU_STATE, TI_CPUSTATE_HALT);

        /* Figure out the hardware revision. */
        switch(CSR_READ_4(sc, TI_MISC_HOST_CTL) & TI_MHC_CHIP_REV_MASK) {
        case TI_REV_TIGON_I:
                sc->ti_hwrev = TI_HWREV_TIGON;
                break;
        case TI_REV_TIGON_II:
                sc->ti_hwrev = TI_HWREV_TIGON_II;
                break;
        default:
                if_printf(ifp, "unsupported chip revision\n");
                return(ENODEV);
        }

        /* Do special setup for Tigon 2. */
        if (sc->ti_hwrev == TI_HWREV_TIGON_II) {
                TI_SETBIT(sc, TI_CPU_CTL_B, TI_CPUSTATE_HALT);
                TI_SETBIT(sc, TI_MISC_LOCAL_CTL, TI_MLC_SRAM_BANK_512K);
                TI_SETBIT(sc, TI_MISC_CONF, TI_MCR_SRAM_SYNCHRONOUS);
        }

        /* Set up the PCI state register. */
        CSR_WRITE_4(sc, TI_PCI_STATE, TI_PCI_READ_CMD|TI_PCI_WRITE_CMD);
        if (sc->ti_hwrev == TI_HWREV_TIGON_II) {
                TI_SETBIT(sc, TI_PCI_STATE, TI_PCISTATE_USE_MEM_RD_MULT);
        }

        /* Clear the read/write max DMA parameters. */
        TI_CLRBIT(sc, TI_PCI_STATE, (TI_PCISTATE_WRITE_MAXDMA|
            TI_PCISTATE_READ_MAXDMA));

        /* Get cache line size. */
        cacheline = CSR_READ_4(sc, TI_PCI_BIST) & 0xFF;

        /*
         * If the system has set enabled the PCI memory write
         * and invalidate command in the command register, set
         * the write max parameter accordingly. This is necessary
         * to use MWI with the Tigon 2.
         */
        if (CSR_READ_4(sc, TI_PCI_CMDSTAT) & PCIM_CMD_MWIEN) {
                switch(cacheline) {
                case 1:
                case 4:
                case 8:
                case 16:
                case 32:
                case 64:
                        break;
                default:
                /* Disable PCI memory write and invalidate. */
                        if (bootverbose) {
                                if_printf(ifp, "cache line size %d not "
                                          "supported; disabling PCI MWI\n",
                                          cacheline);
                        }
                        CSR_WRITE_4(sc, TI_PCI_CMDSTAT, CSR_READ_4(sc,
                            TI_PCI_CMDSTAT) & ~PCIM_CMD_MWIEN);
                        break;
                }
        }

        TI_SETBIT(sc, TI_PCI_STATE, pci_writemax);

        /* This sets the min dma param all the way up (0xff). */
        TI_SETBIT(sc, TI_PCI_STATE, TI_PCISTATE_MINDMA);

        /* Configure DMA variables. */
#if BYTE_ORDER == BIG_ENDIAN
        CSR_WRITE_4(sc, TI_GCR_OPMODE, TI_OPMODE_BYTESWAP_BD |
            TI_OPMODE_BYTESWAP_DATA | TI_OPMODE_WORDSWAP_BD |
            TI_OPMODE_WARN_ENB | TI_OPMODE_FATAL_ENB |
            TI_OPMODE_DONT_FRAG_JUMBO);
#else
        CSR_WRITE_4(sc, TI_GCR_OPMODE, TI_OPMODE_BYTESWAP_DATA|
            TI_OPMODE_WORDSWAP_BD|TI_OPMODE_DONT_FRAG_JUMBO|
            TI_OPMODE_WARN_ENB|TI_OPMODE_FATAL_ENB);
#endif

        /*
         * Only allow 1 DMA channel to be active at a time.
         * I don't think this is a good idea, but without it
         * the firmware racks up lots of nicDmaReadRingFull
         * errors.  This is not compatible with hardware checksums.
         */
        if (ifp->if_hwassist == 0)
                TI_SETBIT(sc, TI_GCR_OPMODE, TI_OPMODE_1_DMA_ACTIVE);

        /* Recommended settings from Tigon manual. */
        CSR_WRITE_4(sc, TI_GCR_DMA_WRITECFG, TI_DMA_STATE_THRESH_8W);
        CSR_WRITE_4(sc, TI_GCR_DMA_READCFG, TI_DMA_STATE_THRESH_8W);

        if (ti_64bitslot_war(sc)) {
                if_printf(ifp, "bios thinks we're in a 64 bit slot, "
                          "but we aren't");
                return(EINVAL);
        }

        return(0);
}

/*
 * Initialize the general information block and firmware, and
 * start the CPU(s) running.
 */
static int
ti_gibinit(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ti_rcb *rcb;
        int i;

        /* Disable interrupts for now. */
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, 1);

        /* Tell the chip where to find the general information block. */
        CSR_WRITE_4(sc, TI_GCR_GENINFO_HI, 0);
        CSR_WRITE_4(sc, TI_GCR_GENINFO_LO, vtophys(&sc->ti_rdata->ti_info));

        /* Load the firmware into SRAM. */
        ti_loadfw(sc);

        /* Set up the contents of the general info and ring control blocks. */

        /* Set up the event ring and producer pointer. */
        rcb = &sc->ti_rdata->ti_info.ti_ev_rcb;

        TI_HOSTADDR(rcb->ti_hostaddr) = vtophys(&sc->ti_rdata->ti_event_ring);
        rcb->ti_flags = 0;
        TI_HOSTADDR(sc->ti_rdata->ti_info.ti_ev_prodidx_ptr) =
            vtophys(&sc->ti_ev_prodidx);
        sc->ti_ev_prodidx.ti_idx = 0;
        CSR_WRITE_4(sc, TI_GCR_EVENTCONS_IDX, 0);
        sc->ti_ev_saved_considx = 0;

        /* Set up the command ring and producer mailbox. */
        rcb = &sc->ti_rdata->ti_info.ti_cmd_rcb;

        sc->ti_rdata->ti_cmd_ring =
            (struct ti_cmd_desc *)(sc->ti_vhandle + TI_GCR_CMDRING);
        TI_HOSTADDR(rcb->ti_hostaddr) = TI_GCR_NIC_ADDR(TI_GCR_CMDRING);
        rcb->ti_flags = 0;
        rcb->ti_max_len = 0;
        for (i = 0; i < TI_CMD_RING_CNT; i++)
                CSR_WRITE_4(sc, TI_GCR_CMDRING + (i * 4), 0);
        CSR_WRITE_4(sc, TI_GCR_CMDCONS_IDX, 0);
        CSR_WRITE_4(sc, TI_MB_CMDPROD_IDX, 0);
        sc->ti_cmd_saved_prodidx = 0;

        /*
         * Assign the address of the stats refresh buffer.
         * We re-use the current stats buffer for this to
         * conserve memory.
         */
        TI_HOSTADDR(sc->ti_rdata->ti_info.ti_refresh_stats_ptr) =
            vtophys(&sc->ti_rdata->ti_info.ti_stats);

        /* Set up the standard receive ring. */
        rcb = &sc->ti_rdata->ti_info.ti_std_rx_rcb;
        TI_HOSTADDR(rcb->ti_hostaddr) = vtophys(&sc->ti_rdata->ti_rx_std_ring);
        rcb->ti_max_len = TI_FRAMELEN;
        rcb->ti_flags = 0;
        if (ifp->if_hwassist)
                rcb->ti_flags |= TI_RCB_FLAG_TCP_UDP_CKSUM |
                     TI_RCB_FLAG_IP_CKSUM | TI_RCB_FLAG_NO_PHDR_CKSUM;
        rcb->ti_flags |= TI_RCB_FLAG_VLAN_ASSIST;

        /* Set up the jumbo receive ring. */
        rcb = &sc->ti_rdata->ti_info.ti_jumbo_rx_rcb;
        TI_HOSTADDR(rcb->ti_hostaddr) =
            vtophys(&sc->ti_rdata->ti_rx_jumbo_ring);
        rcb->ti_max_len = TI_JUMBO_FRAMELEN;
        rcb->ti_flags = 0;
        if (ifp->if_hwassist)
                rcb->ti_flags |= TI_RCB_FLAG_TCP_UDP_CKSUM |
                     TI_RCB_FLAG_IP_CKSUM | TI_RCB_FLAG_NO_PHDR_CKSUM;
        rcb->ti_flags |= TI_RCB_FLAG_VLAN_ASSIST;

        /*
         * Set up the mini ring. Only activated on the
         * Tigon 2 but the slot in the config block is
         * still there on the Tigon 1.
         */
        rcb = &sc->ti_rdata->ti_info.ti_mini_rx_rcb;
        TI_HOSTADDR(rcb->ti_hostaddr) =
            vtophys(&sc->ti_rdata->ti_rx_mini_ring);
        rcb->ti_max_len = MHLEN - ETHER_ALIGN;
        if (sc->ti_hwrev == TI_HWREV_TIGON)
                rcb->ti_flags = TI_RCB_FLAG_RING_DISABLED;
        else
                rcb->ti_flags = 0;
        if (ifp->if_hwassist)
                rcb->ti_flags |= TI_RCB_FLAG_TCP_UDP_CKSUM |
                     TI_RCB_FLAG_IP_CKSUM | TI_RCB_FLAG_NO_PHDR_CKSUM;
        rcb->ti_flags |= TI_RCB_FLAG_VLAN_ASSIST;

        /*
         * Set up the receive return ring.
         */
        rcb = &sc->ti_rdata->ti_info.ti_return_rcb;
        TI_HOSTADDR(rcb->ti_hostaddr) =
            vtophys(&sc->ti_rdata->ti_rx_return_ring);
        rcb->ti_flags = 0;
        rcb->ti_max_len = TI_RETURN_RING_CNT;
        TI_HOSTADDR(sc->ti_rdata->ti_info.ti_return_prodidx_ptr) =
            vtophys(&sc->ti_return_prodidx);

        /*
         * Set up the tx ring. Note: for the Tigon 2, we have the option
         * of putting the transmit ring in the host's address space and
         * letting the chip DMA it instead of leaving the ring in the NIC's
         * memory and accessing it through the shared memory region. We
         * do this for the Tigon 2, but it doesn't work on the Tigon 1,
         * so we have to revert to the shared memory scheme if we detect
         * a Tigon 1 chip.
         */
        CSR_WRITE_4(sc, TI_WINBASE, TI_TX_RING_BASE);
        if (sc->ti_hwrev == TI_HWREV_TIGON) {
                sc->ti_rdata->ti_tx_ring_nic =
                    (struct ti_tx_desc *)(sc->ti_vhandle + TI_WINDOW);
        }
        bzero(sc->ti_rdata->ti_tx_ring,
            TI_TX_RING_CNT * sizeof(struct ti_tx_desc));
        rcb = &sc->ti_rdata->ti_info.ti_tx_rcb;
        if (sc->ti_hwrev == TI_HWREV_TIGON)
                rcb->ti_flags = 0;
        else
                rcb->ti_flags = TI_RCB_FLAG_HOST_RING;
        rcb->ti_flags |= TI_RCB_FLAG_VLAN_ASSIST;
        if (ifp->if_hwassist)
                rcb->ti_flags |= TI_RCB_FLAG_TCP_UDP_CKSUM |
                     TI_RCB_FLAG_IP_CKSUM | TI_RCB_FLAG_NO_PHDR_CKSUM;
        rcb->ti_max_len = TI_TX_RING_CNT;
        if (sc->ti_hwrev == TI_HWREV_TIGON)
                TI_HOSTADDR(rcb->ti_hostaddr) = TI_TX_RING_BASE;
        else
                TI_HOSTADDR(rcb->ti_hostaddr) =
                    vtophys(&sc->ti_rdata->ti_tx_ring);
        TI_HOSTADDR(sc->ti_rdata->ti_info.ti_tx_considx_ptr) =
            vtophys(&sc->ti_tx_considx);

        /* Set up tuneables */
        if (ifp->if_mtu > (ETHERMTU + ETHER_HDR_LEN + ETHER_CRC_LEN))
                CSR_WRITE_4(sc, TI_GCR_RX_COAL_TICKS,
                    (sc->ti_rx_coal_ticks / 10));
        else
                CSR_WRITE_4(sc, TI_GCR_RX_COAL_TICKS, sc->ti_rx_coal_ticks);
        CSR_WRITE_4(sc, TI_GCR_TX_COAL_TICKS, sc->ti_tx_coal_ticks);
        CSR_WRITE_4(sc, TI_GCR_STAT_TICKS, sc->ti_stat_ticks);
        CSR_WRITE_4(sc, TI_GCR_RX_MAX_COAL_BD, sc->ti_rx_max_coal_bds);
        CSR_WRITE_4(sc, TI_GCR_TX_MAX_COAL_BD, sc->ti_tx_max_coal_bds);
        CSR_WRITE_4(sc, TI_GCR_TX_BUFFER_RATIO, sc->ti_tx_buf_ratio);

        /* Turn interrupts on. */
        CSR_WRITE_4(sc, TI_GCR_MASK_INTRS, 0);
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, 0);

        /* Start CPU. */
        TI_CLRBIT(sc, TI_CPU_STATE, (TI_CPUSTATE_HALT|TI_CPUSTATE_STEP));

        return(0);
}

/*
 * Probe for a Tigon chip. Check the PCI vendor and device IDs
 * against our list and return its name if we find a match.
 */
static int
ti_probe(device_t dev)
{
        struct ti_type *t;
        uint16_t vendor, product;

        vendor = pci_get_vendor(dev);
        product = pci_get_device(dev);

        for (t = ti_devs; t->ti_name != NULL; t++) {
                if (vendor == t->ti_vid && product == t->ti_did) {
                        device_set_desc(dev, t->ti_name);
                        return(0);
                }
        }

        return(ENXIO);
}

static int
ti_attach(device_t dev)
{
        struct ti_softc *sc;
        struct ifnet *ifp;
        int error = 0, rid;
        uint8_t eaddr[ETHER_ADDR_LEN];

        sc = device_get_softc(dev);
        ifp = &sc->arpcom.ac_if;
        if_initname(ifp, device_get_name(dev), device_get_unit(dev));
        ifp->if_capabilities = IFCAP_HWCSUM |
            IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_MTU;
        ifp->if_capenable = ifp->if_capabilities;

        pci_enable_busmaster(dev);

        /*
         * Initialize media before any possible error may occur,
         * so we can destroy it unconditionally, if an error occurs later on.
         */
        ifmedia_init(&sc->ifmedia, IFM_IMASK, ti_ifmedia_upd, ti_ifmedia_sts);

        rid = TI_PCI_LOMEM;
        sc->ti_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
            RF_ACTIVE);

        if (sc->ti_res == NULL) {
                device_printf(dev, "couldn't map memory\n");
                error = ENXIO;
                goto fail;
        }

        sc->ti_btag = rman_get_bustag(sc->ti_res);
        sc->ti_bhandle = rman_get_bushandle(sc->ti_res);
        sc->ti_vhandle = (vm_offset_t)rman_get_virtual(sc->ti_res);

        /* Allocate interrupt */
        rid = 0;
        sc->ti_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
            RF_SHAREABLE | RF_ACTIVE);
        if (sc->ti_irq == NULL) {
                device_printf(dev, "couldn't map interrupt\n");
                error = ENXIO;
                goto fail;
        }

        if (ti_chipinit(sc)) {
                device_printf(dev, "chip initialization failed\n");
                error = ENXIO;
                goto fail;
        }

        /* Zero out the NIC's on-board SRAM. */
        ti_mem(sc, 0x2000, 0x100000 - 0x2000,  NULL);

        /* Init again -- zeroing memory may have clobbered some registers. */
        if (ti_chipinit(sc)) {
                device_printf(dev, "chip initialization failed\n");
                error = ENXIO;
                goto fail;
        }

        /*
         * Get station address from the EEPROM. Note: the manual states
         * that the MAC address is at offset 0x8c, however the data is
         * stored as two longwords (since that's how it's loaded into
         * the NIC). This means the MAC address is actually preceeded
         * by two zero bytes. We need to skip over those.
         */
        if (ti_read_eeprom(sc, eaddr, TI_EE_MAC_OFFSET + 2, ETHER_ADDR_LEN)) {
                device_printf(dev, "failed to read station address\n");
                error = ENXIO;
                goto fail;
        }

        /* Allocate the general information block and ring buffers. */
        sc->ti_rdata = contigmalloc(sizeof(struct ti_ring_data), M_DEVBUF,
            M_WAITOK | M_ZERO, 0, 0xffffffff, PAGE_SIZE, 0);

        if (sc->ti_rdata == NULL) {
                device_printf(dev, "no memory for list buffers!\n");
                error = ENXIO;
                goto fail;
        }

        /* Try to allocate memory for jumbo buffers. */
        if (ti_alloc_jumbo_mem(sc)) {
                device_printf(dev, "jumbo buffer allocation failed\n");
                error = ENXIO;
                goto fail;
        }

        /*
         * We really need a better way to tell a 1000baseT card
         * from a 1000baseSX one, since in theory there could be
         * OEMed 1000baseT cards from lame vendors who aren't
         * clever enough to change the PCI ID. For the moment
         * though, the AceNIC is the only copper card available.
         */
        if (pci_get_vendor(dev) == ALT_VENDORID &&
            pci_get_device(dev) == ALT_DEVICEID_ACENIC_COPPER)
                sc->ti_copper = 1;
        /* Ok, it's not the only copper card available. */
        if (pci_get_vendor(dev) == NG_VENDORID &&
            pci_get_device(dev) == NG_DEVICEID_GA620T)
                sc->ti_copper = 1;

        /* Set default tuneable values. */
        sc->ti_stat_ticks = 2 * TI_TICKS_PER_SEC;
        sc->ti_rx_coal_ticks = TI_TICKS_PER_SEC / 5000;
        sc->ti_tx_coal_ticks = TI_TICKS_PER_SEC / 500;
        sc->ti_rx_max_coal_bds = 64;
        sc->ti_tx_max_coal_bds = 128;
        sc->ti_tx_buf_ratio = 21;

        /* Set up ifnet structure */
        ifp->if_softc = sc;
        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_ioctl = ti_ioctl;
        ifp->if_start = ti_start;
        ifp->if_watchdog = ti_watchdog;
        ifp->if_init = ti_init;
        ifp->if_mtu = ETHERMTU;
        ifq_set_maxlen(&ifp->if_snd, TI_TX_RING_CNT - 1);
        ifq_set_ready(&ifp->if_snd);

        /* Set up ifmedia support. */
        if (sc->ti_copper) {
                /*
                 * Copper cards allow manual 10/100 mode selection,
                 * but not manual 1000baseT mode selection. Why?
                 * Becuase currently there's no way to specify the
                 * master/slave setting through the firmware interface,
                 * so Alteon decided to just bag it and handle it
                 * via autonegotiation.
                 */
                ifmedia_add(&sc->ifmedia, IFM_ETHER|IFM_10_T, 0, NULL);
                ifmedia_add(&sc->ifmedia,
                    IFM_ETHER|IFM_10_T|IFM_FDX, 0, NULL);
                ifmedia_add(&sc->ifmedia, IFM_ETHER|IFM_100_TX, 0, NULL);
                ifmedia_add(&sc->ifmedia,
                    IFM_ETHER|IFM_100_TX|IFM_FDX, 0, NULL);
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_1000_T, 0, NULL);
                ifmedia_add(&sc->ifmedia,
                    IFM_ETHER|IFM_1000_T | IFM_FDX, 0, NULL);
        } else {
                /* Fiber cards don't support 10/100 modes. */
                ifmedia_add(&sc->ifmedia, IFM_ETHER|IFM_1000_SX, 0, NULL);
                ifmedia_add(&sc->ifmedia,
                    IFM_ETHER|IFM_1000_SX|IFM_FDX, 0, NULL);
        }
        ifmedia_add(&sc->ifmedia, IFM_ETHER|IFM_AUTO, 0, NULL);
        ifmedia_set(&sc->ifmedia, IFM_ETHER|IFM_AUTO);

        /*
         * Call MI attach routine.
         */
        ether_ifattach(ifp, eaddr, NULL);

        error = bus_setup_intr(dev, sc->ti_irq, INTR_NETSAFE,
                               ti_intr, sc, &sc->ti_intrhand, 
                               ifp->if_serializer);
        if (error) {
                device_printf(dev, "couldn't set up irq\n");
                ether_ifdetach(ifp);
                goto fail;
        }

        ifp->if_cpuid = ithread_cpuid(rman_get_start(sc->ti_irq));
        KKASSERT(ifp->if_cpuid >= 0 && ifp->if_cpuid < ncpus);

        return 0;
fail:
        ti_detach(dev);
        return(error);
}

static int
ti_detach(device_t dev)
{
        struct ti_softc *sc = device_get_softc(dev);
        struct ifnet *ifp = &sc->arpcom.ac_if;

        if (device_is_attached(dev)) {
                lwkt_serialize_enter(ifp->if_serializer);
                ti_stop(sc);
                bus_teardown_intr(dev, sc->ti_irq, sc->ti_intrhand);
                lwkt_serialize_exit(ifp->if_serializer);

                ether_ifdetach(ifp);
        }

        if (sc->ti_irq != NULL)
                bus_release_resource(dev, SYS_RES_IRQ, 0, sc->ti_irq);
        if (sc->ti_res != NULL) {
                bus_release_resource(dev, SYS_RES_MEMORY,
                                     TI_PCI_LOMEM, sc->ti_res);
        }
        if (sc->ti_cdata.ti_jumbo_buf != NULL)
                contigfree(sc->ti_cdata.ti_jumbo_buf, TI_JMEM, M_DEVBUF);
        if (sc->ti_rdata != NULL)
                contigfree(sc->ti_rdata, sizeof(struct ti_ring_data), M_DEVBUF);
        ifmedia_removeall(&sc->ifmedia);


        return(0);
}

/*
 * Frame reception handling. This is called if there's a frame
 * on the receive return list.
 *
 * Note: we have to be able to handle three possibilities here:
 * 1) the frame is from the mini receive ring (can only happen)
 *    on Tigon 2 boards)
 * 2) the frame is from the jumbo recieve ring
 * 3) the frame is from the standard receive ring
 */
static void
ti_rxeof(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ti_cmd_desc cmd;

        while(sc->ti_rx_saved_considx != sc->ti_return_prodidx.ti_idx) {
                struct ti_rx_desc *cur_rx;
                uint32_t rxidx;
                struct mbuf *m;
                uint16_t vlan_tag = 0;
                int have_tag = 0;

                cur_rx =
                    &sc->ti_rdata->ti_rx_return_ring[sc->ti_rx_saved_considx];
                rxidx = cur_rx->ti_idx;
                TI_INC(sc->ti_rx_saved_considx, TI_RETURN_RING_CNT);

                if (cur_rx->ti_flags & TI_BDFLAG_VLAN_TAG) {
                        have_tag = 1;
                        vlan_tag = cur_rx->ti_vlan_tag & 0xfff;
                }

                if (cur_rx->ti_flags & TI_BDFLAG_JUMBO_RING) {
                        TI_INC(sc->ti_jumbo, TI_JUMBO_RX_RING_CNT);
                        m = sc->ti_cdata.ti_rx_jumbo_chain[rxidx];
                        sc->ti_cdata.ti_rx_jumbo_chain[rxidx] = NULL;
                        if (cur_rx->ti_flags & TI_BDFLAG_ERROR) {
                                ifp->if_ierrors++;
                                ti_newbuf_jumbo(sc, sc->ti_jumbo, m);
                                continue;
                        }
                        if (ti_newbuf_jumbo(sc, sc->ti_jumbo, NULL) == ENOBUFS) {
                                ifp->if_ierrors++;
                                ti_newbuf_jumbo(sc, sc->ti_jumbo, m);
                                continue;
                        }
                } else if (cur_rx->ti_flags & TI_BDFLAG_MINI_RING) {
                        TI_INC(sc->ti_mini, TI_MINI_RX_RING_CNT);
                        m = sc->ti_cdata.ti_rx_mini_chain[rxidx];
                        sc->ti_cdata.ti_rx_mini_chain[rxidx] = NULL;
                        if (cur_rx->ti_flags & TI_BDFLAG_ERROR) {
                                ifp->if_ierrors++;
                                ti_newbuf_mini(sc, sc->ti_mini, m);
                                continue;
                        }
                        if (ti_newbuf_mini(sc, sc->ti_mini, NULL) == ENOBUFS) {
                                ifp->if_ierrors++;
                                ti_newbuf_mini(sc, sc->ti_mini, m);
                                continue;
                        }
                } else {
                        TI_INC(sc->ti_std, TI_STD_RX_RING_CNT);
                        m = sc->ti_cdata.ti_rx_std_chain[rxidx];
                        sc->ti_cdata.ti_rx_std_chain[rxidx] = NULL;
                        if (cur_rx->ti_flags & TI_BDFLAG_ERROR) {
                                ifp->if_ierrors++;
                                ti_newbuf_std(sc, sc->ti_std, m);
                                continue;
                        }
                        if (ti_newbuf_std(sc, sc->ti_std, NULL) == ENOBUFS) {
                                ifp->if_ierrors++;
                                ti_newbuf_std(sc, sc->ti_std, m);
                                continue;
                        }
                }

                m->m_pkthdr.len = m->m_len = cur_rx->ti_len;
                ifp->if_ipackets++;
                m->m_pkthdr.rcvif = ifp;

                if (ifp->if_hwassist) {
                        m->m_pkthdr.csum_flags |= CSUM_IP_CHECKED |
                            CSUM_DATA_VALID;
                        if ((cur_rx->ti_ip_cksum ^ 0xffff) == 0)
                                m->m_pkthdr.csum_flags |= CSUM_IP_VALID;
                        m->m_pkthdr.csum_data = cur_rx->ti_tcp_udp_cksum;
                }

                /*
                 * If we received a packet with a vlan tag, pass it
                 * to vlan_input() instead of ether_input().
                 */
                if (have_tag)
                        VLAN_INPUT_TAG(m, vlan_tag);
                else
                        ifp->if_input(ifp, m);
        }

        /* Only necessary on the Tigon 1. */
        if (sc->ti_hwrev == TI_HWREV_TIGON)
                CSR_WRITE_4(sc, TI_GCR_RXRETURNCONS_IDX,
                    sc->ti_rx_saved_considx);

        TI_UPDATE_STDPROD(sc, sc->ti_std);
        TI_UPDATE_MINIPROD(sc, sc->ti_mini);
        TI_UPDATE_JUMBOPROD(sc, sc->ti_jumbo);
}

static void
ti_txeof(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ti_tx_desc *cur_tx = NULL;

        /*
         * Go through our tx ring and free mbufs for those
         * frames that have been sent.
         */
        while (sc->ti_tx_saved_considx != sc->ti_tx_considx.ti_idx) {
                uint32_t idx = 0;

                idx = sc->ti_tx_saved_considx;
                if (sc->ti_hwrev == TI_HWREV_TIGON) {
                        if (idx > 383)
                                CSR_WRITE_4(sc, TI_WINBASE,
                                    TI_TX_RING_BASE + 6144);
                        else if (idx > 255)
                                CSR_WRITE_4(sc, TI_WINBASE,
                                    TI_TX_RING_BASE + 4096);
                        else if (idx > 127)
                                CSR_WRITE_4(sc, TI_WINBASE,
                                    TI_TX_RING_BASE + 2048);
                        else
                                CSR_WRITE_4(sc, TI_WINBASE,
                                    TI_TX_RING_BASE);
                        cur_tx = &sc->ti_rdata->ti_tx_ring_nic[idx % 128];
                } else
                        cur_tx = &sc->ti_rdata->ti_tx_ring[idx];
                if (cur_tx->ti_flags & TI_BDFLAG_END)
                        ifp->if_opackets++;
                if (sc->ti_cdata.ti_tx_chain[idx] != NULL) {
                        m_freem(sc->ti_cdata.ti_tx_chain[idx]);
                        sc->ti_cdata.ti_tx_chain[idx] = NULL;
                }
                sc->ti_txcnt--;
                TI_INC(sc->ti_tx_saved_considx, TI_TX_RING_CNT);
                ifp->if_timer = 0;
        }

        if (cur_tx != NULL)
                ifp->if_flags &= ~IFF_OACTIVE;
}

static void
ti_intr(void *xsc)
{
        struct ti_softc *sc = xsc;
        struct ifnet *ifp = &sc->arpcom.ac_if;

#ifdef notdef
        /* Avoid this for now -- checking this register is expensive. */
        /* Make sure this is really our interrupt. */
        if ((CSR_READ_4(sc, TI_MISC_HOST_CTL) & TI_MHC_INTSTATE) == 0)
                return;
#endif

        /* Ack interrupt and stop others from occuring. */
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, 1);

        if (ifp->if_flags & IFF_RUNNING) {
                /* Check RX return ring producer/consumer */
                ti_rxeof(sc);

                /* Check TX ring producer/consumer */
                ti_txeof(sc);
        }

        ti_handle_events(sc);

        /* Re-enable interrupts. */
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, 0);

        if ((ifp->if_flags & IFF_RUNNING) && !ifq_is_empty(&ifp->if_snd))
                if_devstart(ifp);
}

static void
ti_stats_update(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;

        ifp->if_collisions +=
           (sc->ti_rdata->ti_info.ti_stats.dot3StatsSingleCollisionFrames +
           sc->ti_rdata->ti_info.ti_stats.dot3StatsMultipleCollisionFrames +
           sc->ti_rdata->ti_info.ti_stats.dot3StatsExcessiveCollisions +
           sc->ti_rdata->ti_info.ti_stats.dot3StatsLateCollisions) -
           ifp->if_collisions;
}

/*
 * Encapsulate an mbuf chain in the tx ring  by coupling the mbuf data
 * pointers to descriptors.
 */
static int
ti_encap(struct ti_softc *sc, struct mbuf *m_head, uint32_t *txidx)
{
        struct ti_tx_desc *f = NULL;
        struct mbuf *m;
        uint32_t cnt = 0, cur, frag;
        uint16_t csum_flags = 0, vlan_tag = 0, vlan_flag = 0;

        if (m_head->m_flags & M_VLANTAG) {
                vlan_tag = m_head->m_pkthdr.ether_vlantag;
                vlan_flag = TI_BDFLAG_VLAN_TAG;
        }

        m = m_head;
        cur = frag = *txidx;

        if (m_head->m_pkthdr.csum_flags) {
                if (m_head->m_pkthdr.csum_flags & CSUM_IP)
                        csum_flags |= TI_BDFLAG_IP_CKSUM;
                if (m_head->m_pkthdr.csum_flags & (CSUM_TCP | CSUM_UDP))
                        csum_flags |= TI_BDFLAG_TCP_UDP_CKSUM;
                if (m_head->m_flags & M_LASTFRAG)
                        csum_flags |= TI_BDFLAG_IP_FRAG_END;
                else if (m_head->m_flags & M_FRAG)
                        csum_flags |= TI_BDFLAG_IP_FRAG;
        }
        /*
         * Start packing the mbufs in this chain into
         * the fragment pointers. Stop when we run out
         * of fragments or hit the end of the mbuf chain.
         */
        for (m = m_head; m != NULL; m = m->m_next) {
                if (m->m_len != 0) {
                        if (sc->ti_hwrev == TI_HWREV_TIGON) {
                                if (frag > 383)
                                        CSR_WRITE_4(sc, TI_WINBASE,
                                            TI_TX_RING_BASE + 6144);
                                else if (frag > 255)
                                        CSR_WRITE_4(sc, TI_WINBASE,
                                            TI_TX_RING_BASE + 4096);
                                else if (frag > 127)
                                        CSR_WRITE_4(sc, TI_WINBASE,
                                            TI_TX_RING_BASE + 2048);
                                else
                                        CSR_WRITE_4(sc, TI_WINBASE,
                                            TI_TX_RING_BASE);
                                f = &sc->ti_rdata->ti_tx_ring_nic[frag % 128];
                        } else
                                f = &sc->ti_rdata->ti_tx_ring[frag];
                        if (sc->ti_cdata.ti_tx_chain[frag] != NULL)
                                break;
                        TI_HOSTADDR(f->ti_addr) = vtophys(mtod(m, vm_offset_t));
                        f->ti_len = m->m_len;
                        f->ti_flags = csum_flags | vlan_flag;
                        f->ti_vlan_tag = vlan_tag & 0xfff;

                        /*
                         * Sanity check: avoid coming within 16 descriptors
                         * of the end of the ring.
                         */
                        if ((TI_TX_RING_CNT - (sc->ti_txcnt + cnt)) < 16)
                                return(ENOBUFS);
                        cur = frag;
                        TI_INC(frag, TI_TX_RING_CNT);
                        cnt++;
                }
        }

        if (m != NULL)
                return(ENOBUFS);

        if (frag == sc->ti_tx_saved_considx)
                return(ENOBUFS);

        if (sc->ti_hwrev == TI_HWREV_TIGON)
                sc->ti_rdata->ti_tx_ring_nic[cur % 128].ti_flags |=
                    TI_BDFLAG_END;
        else
                sc->ti_rdata->ti_tx_ring[cur].ti_flags |= TI_BDFLAG_END;
        sc->ti_cdata.ti_tx_chain[cur] = m_head;
        sc->ti_txcnt += cnt;

        *txidx = frag;

        return(0);
}

/*
 * Main transmit routine. To avoid having to do mbuf copies, we put pointers
 * to the mbuf data regions directly in the transmit descriptors.
 */
static void
ti_start(struct ifnet *ifp)
{
        struct ti_softc *sc = ifp->if_softc;
        struct mbuf *m_head = NULL;
        uint32_t prodidx = 0;
        int need_trans;

        prodidx = CSR_READ_4(sc, TI_MB_SENDPROD_IDX);

        need_trans = 0;
        while(sc->ti_cdata.ti_tx_chain[prodidx] == NULL) {
                m_head = ifq_dequeue(&ifp->if_snd, NULL);
                if (m_head == NULL)
                        break;

                /*
                 * XXX
                 * safety overkill.  If this is a fragmented packet chain
                 * with delayed TCP/UDP checksums, then only encapsulate
                 * it if we have enough descriptors to handle the entire
                 * chain at once.
                 * (paranoia -- may not actually be needed)
                 */
                if (m_head->m_flags & M_FIRSTFRAG &&
                    m_head->m_pkthdr.csum_flags & (CSUM_DELAY_DATA)) {
                        if ((TI_TX_RING_CNT - sc->ti_txcnt) <
                            m_head->m_pkthdr.csum_data + 16) {
                                ifp->if_flags |= IFF_OACTIVE;
                                ifq_prepend(&ifp->if_snd, m_head);
                                break;
                        }
                }

                /*
                 * Pack the data into the transmit ring. If we
                 * don't have room, set the OACTIVE flag and wait
                 * for the NIC to drain the ring.
                 */
                if (ti_encap(sc, m_head, &prodidx)) {
                        ifp->if_flags |= IFF_OACTIVE;
                        ifq_prepend(&ifp->if_snd, m_head);
                        break;
                }
                need_trans = 1;

                ETHER_BPF_MTAP(ifp, m_head);
        }

        if (!need_trans)
                return;

        /* Transmit */
        CSR_WRITE_4(sc, TI_MB_SENDPROD_IDX, prodidx);

        /*
         * Set a timeout in case the chip goes out to lunch.
         */
        ifp->if_timer = 5;
}

static void
ti_init(void *xsc)
{
        struct ti_softc *sc = xsc;

        /* Cancel pending I/O and flush buffers. */
        ti_stop(sc);

        /* Init the gen info block, ring control blocks and firmware. */
        if (ti_gibinit(sc)) {
                if_printf(&sc->arpcom.ac_if, "initialization failure\n");
                return;
        }
}

static void
ti_init2(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ti_cmd_desc cmd;
        uint16_t *m;
        struct ifmedia *ifm;
        int tmp;

        /* Specify MTU and interface index. */
        CSR_WRITE_4(sc, TI_GCR_IFINDEX, ifp->if_dunit);
        CSR_WRITE_4(sc, TI_GCR_IFMTU, ifp->if_mtu +
            ETHER_HDR_LEN + ETHER_CRC_LEN);
        TI_DO_CMD(TI_CMD_UPDATE_GENCOM, 0, 0);

        /* Load our MAC address. */
        m = (uint16_t *)&sc->arpcom.ac_enaddr[0];
        CSR_WRITE_4(sc, TI_GCR_PAR0, htons(m[0]));
        CSR_WRITE_4(sc, TI_GCR_PAR1, (htons(m[1]) << 16) | htons(m[2]));
        TI_DO_CMD(TI_CMD_SET_MAC_ADDR, 0, 0);

        /* Enable or disable promiscuous mode as needed. */
        if (ifp->if_flags & IFF_PROMISC)
                TI_DO_CMD(TI_CMD_SET_PROMISC_MODE, TI_CMD_CODE_PROMISC_ENB, 0);
        else
                TI_DO_CMD(TI_CMD_SET_PROMISC_MODE, TI_CMD_CODE_PROMISC_DIS, 0);

        /* Program multicast filter. */
        ti_setmulti(sc);

        /*
         * If this is a Tigon 1, we should tell the
         * firmware to use software packet filtering.
         */
        if (sc->ti_hwrev == TI_HWREV_TIGON)
                TI_DO_CMD(TI_CMD_FDR_FILTERING, TI_CMD_CODE_FILT_ENB, 0);

        /* Init RX ring. */
        ti_init_rx_ring_std(sc);

        /* Init jumbo RX ring. */
        if (ifp->if_mtu > (ETHERMTU + ETHER_HDR_LEN + ETHER_CRC_LEN))
                ti_init_rx_ring_jumbo(sc);

        /*
         * If this is a Tigon 2, we can also configure the
         * mini ring.
         */
        if (sc->ti_hwrev == TI_HWREV_TIGON_II)
                ti_init_rx_ring_mini(sc);

        CSR_WRITE_4(sc, TI_GCR_RXRETURNCONS_IDX, 0);
        sc->ti_rx_saved_considx = 0;

        /* Init TX ring. */
        ti_init_tx_ring(sc);

        /* Tell firmware we're alive. */
        TI_DO_CMD(TI_CMD_HOST_STATE, TI_CMD_CODE_STACK_UP, 0);

        /* Enable host interrupts. */
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, 0);

        ifp->if_flags |= IFF_RUNNING;
        ifp->if_flags &= ~IFF_OACTIVE;

        /*
         * Make sure to set media properly. We have to do this
         * here since we have to issue commands in order to set
         * the link negotiation and we can't issue commands until
         * the firmware is running.
         */
        ifm = &sc->ifmedia;
        tmp = ifm->ifm_media;
        ifm->ifm_media = ifm->ifm_cur->ifm_media;
        ti_ifmedia_upd(ifp);
        ifm->ifm_media = tmp;
}

/*
 * Set media options.
 */
static int
ti_ifmedia_upd(struct ifnet *ifp)
{
        struct ti_softc *sc = ifp->if_softc;
        struct ifmedia *ifm = &sc->ifmedia;
        struct ti_cmd_desc cmd;

        if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
                return(EINVAL);

        switch(IFM_SUBTYPE(ifm->ifm_media)) {
        case IFM_AUTO:
                CSR_WRITE_4(sc, TI_GCR_GLINK, TI_GLNK_PREF | TI_GLNK_1000MB |
                    TI_GLNK_FULL_DUPLEX | TI_GLNK_RX_FLOWCTL_Y |
                    TI_GLNK_AUTONEGENB | TI_GLNK_ENB);
                CSR_WRITE_4(sc, TI_GCR_LINK, TI_LNK_100MB | TI_LNK_10MB |
                    TI_LNK_FULL_DUPLEX | TI_LNK_HALF_DUPLEX |
                    TI_LNK_AUTONEGENB | TI_LNK_ENB);
                TI_DO_CMD(TI_CMD_LINK_NEGOTIATION,
                    TI_CMD_CODE_NEGOTIATE_BOTH, 0);
                break;
        case IFM_1000_SX:
        case IFM_1000_T:
                CSR_WRITE_4(sc, TI_GCR_GLINK, TI_GLNK_PREF|TI_GLNK_1000MB |
                    TI_GLNK_RX_FLOWCTL_Y | TI_GLNK_ENB);
                CSR_WRITE_4(sc, TI_GCR_LINK, 0);
                if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
                        TI_SETBIT(sc, TI_GCR_GLINK, TI_GLNK_FULL_DUPLEX);
                TI_DO_CMD(TI_CMD_LINK_NEGOTIATION,
                    TI_CMD_CODE_NEGOTIATE_GIGABIT, 0);
                break;
        case IFM_100_FX:
        case IFM_10_FL:
        case IFM_100_TX:
        case IFM_10_T:
                CSR_WRITE_4(sc, TI_GCR_GLINK, 0);
                CSR_WRITE_4(sc, TI_GCR_LINK, TI_LNK_ENB | TI_LNK_PREF);
                if (IFM_SUBTYPE(ifm->ifm_media) == IFM_100_FX ||
                    IFM_SUBTYPE(ifm->ifm_media) == IFM_100_TX)
                        TI_SETBIT(sc, TI_GCR_LINK, TI_LNK_100MB);
                else
                        TI_SETBIT(sc, TI_GCR_LINK, TI_LNK_10MB);
                if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
                        TI_SETBIT(sc, TI_GCR_LINK, TI_LNK_FULL_DUPLEX);
                else
                        TI_SETBIT(sc, TI_GCR_LINK, TI_LNK_HALF_DUPLEX);
                TI_DO_CMD(TI_CMD_LINK_NEGOTIATION,
                    TI_CMD_CODE_NEGOTIATE_10_100, 0);
                break;
        }

        return(0);
}

/*
 * Report current media status.
 */
static void
ti_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
{
        struct ti_softc *sc = ifp->if_softc;
        uint32_t media = 0;

        ifmr->ifm_status = IFM_AVALID;
        ifmr->ifm_active = IFM_ETHER;

        if (sc->ti_linkstat == TI_EV_CODE_LINK_DOWN)
                return;

        ifmr->ifm_status |= IFM_ACTIVE;

        if (sc->ti_linkstat == TI_EV_CODE_GIG_LINK_UP) {
                media = CSR_READ_4(sc, TI_GCR_GLINK_STAT);
                if (sc->ti_copper)
                        ifmr->ifm_active |= IFM_1000_T;
                else
                        ifmr->ifm_active |= IFM_1000_SX;
                if (media & TI_GLNK_FULL_DUPLEX)
                        ifmr->ifm_active |= IFM_FDX;
                else
                        ifmr->ifm_active |= IFM_HDX;
        } else if (sc->ti_linkstat == TI_EV_CODE_LINK_UP) {
                media = CSR_READ_4(sc, TI_GCR_LINK_STAT);
                if (sc->ti_copper) {
                        if (media & TI_LNK_100MB)
                                ifmr->ifm_active |= IFM_100_TX;
                        if (media & TI_LNK_10MB)
                                ifmr->ifm_active |= IFM_10_T;
                } else {
                        if (media & TI_LNK_100MB)
                                ifmr->ifm_active |= IFM_100_FX;
                        if (media & TI_LNK_10MB)
                                ifmr->ifm_active |= IFM_10_FL;
                }
                if (media & TI_LNK_FULL_DUPLEX)
                        ifmr->ifm_active |= IFM_FDX;
                if (media & TI_LNK_HALF_DUPLEX)
                        ifmr->ifm_active |= IFM_HDX;
        }
}

static int
ti_ioctl(struct ifnet *ifp, u_long command, caddr_t data, struct ucred *cr)
{
        struct ti_softc *sc = ifp->if_softc;
        struct ifreq *ifr = (struct ifreq *) data;
        struct ti_cmd_desc cmd;
        int error = 0, mask;

        switch(command) {
        case SIOCSIFMTU:
                if (ifr->ifr_mtu > TI_JUMBO_MTU)
                        error = EINVAL;
                else {
                        ifp->if_mtu = ifr->ifr_mtu;
                        ti_init(sc);
                }
                break;
        case SIOCSIFFLAGS:
                if (ifp->if_flags & IFF_UP) {
                        /*
                         * If only the state of the PROMISC flag changed,
                         * then just use the 'set promisc mode' command
                         * instead of reinitializing the entire NIC. Doing
                         * a full re-init means reloading the firmware and
                         * waiting for it to start up, which may take a
                         * second or two.
                         */
                        if (ifp->if_flags & IFF_RUNNING &&
                            ifp->if_flags & IFF_PROMISC &&
                            !(sc->ti_if_flags & IFF_PROMISC)) {
                                TI_DO_CMD(TI_CMD_SET_PROMISC_MODE,
                                    TI_CMD_CODE_PROMISC_ENB, 0);
                        } else if (ifp->if_flags & IFF_RUNNING &&
                            !(ifp->if_flags & IFF_PROMISC) &&
                            sc->ti_if_flags & IFF_PROMISC) {
                                TI_DO_CMD(TI_CMD_SET_PROMISC_MODE,
                                    TI_CMD_CODE_PROMISC_DIS, 0);
                        } else
                                ti_init(sc);
                } else if (ifp->if_flags & IFF_RUNNING) {
                        ti_stop(sc);
                }
                sc->ti_if_flags = ifp->if_flags;
                error = 0;
                break;
        case SIOCADDMULTI:
        case SIOCDELMULTI:
                if (ifp->if_flags & IFF_RUNNING) {
                        ti_setmulti(sc);
                        error = 0;
                }
                break;
        case SIOCSIFMEDIA:
        case SIOCGIFMEDIA:
                error = ifmedia_ioctl(ifp, ifr, &sc->ifmedia, command);
                break;
        case SIOCSIFCAP:
                mask = ifr->ifr_reqcap ^ ifp->if_capenable;
                if (mask & IFCAP_HWCSUM) {
                        if (IFCAP_HWCSUM & ifp->if_capenable)
                                ifp->if_capenable &= ~IFCAP_HWCSUM;
                        else
                                ifp->if_capenable |= IFCAP_HWCSUM;
                        if (ifp->if_flags & IFF_RUNNING)
                                ti_init(sc);
                }
                error = 0;
                break;
        default:
                error = ether_ioctl(ifp, command, data);
                break;
        }
        return(error);
}

static void
ti_watchdog(struct ifnet *ifp)
{
        struct ti_softc *sc = ifp->if_softc;

        if_printf(ifp, "watchdog timeout -- resetting\n");
        ti_stop(sc);
        ti_init(sc);

        ifp->if_oerrors++;

        if (!ifq_is_empty(&ifp->if_snd))
                if_devstart(ifp);
}

/*
 * Stop the adapter and free any mbufs allocated to the
 * RX and TX lists.
 */
static void
ti_stop(struct ti_softc *sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ti_cmd_desc cmd;

        /* Disable host interrupts. */
        CSR_WRITE_4(sc, TI_MB_HOSTINTR, 1);
        /*
         * Tell firmware we're shutting down.
         */
        TI_DO_CMD(TI_CMD_HOST_STATE, TI_CMD_CODE_STACK_DOWN, 0);

        /* Halt and reinitialize. */
        ti_chipinit(sc);
        ti_mem(sc, 0x2000, 0x100000 - 0x2000, NULL);
        ti_chipinit(sc);

        /* Free the RX lists. */
        ti_free_rx_ring_std(sc);

        /* Free jumbo RX list. */
        ti_free_rx_ring_jumbo(sc);

        /* Free mini RX list. */
        ti_free_rx_ring_mini(sc);

        /* Free TX buffers. */
        ti_free_tx_ring(sc);

        sc->ti_ev_prodidx.ti_idx = 0;
        sc->ti_return_prodidx.ti_idx = 0;
        sc->ti_tx_considx.ti_idx = 0;
        sc->ti_tx_saved_considx = TI_TXCONS_UNSET;

        ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
}

/*
 * Stop all chip I/O so that the kernel's probe routines don't
 * get confused by errant DMAs when rebooting.
 */
static void
ti_shutdown(device_t dev)
{
        struct ti_softc *sc = device_get_softc(dev);

        ti_chipinit(sc);
}