Make all network interrupt service routines MPSAFE part 1/3.

[dragonfly.git] / sys / dev / netif / cs / if_cs.c

/*
 * Copyright (c) 1997,1998 Maxim Bolotin and Oleg Sharoiko.
 * 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 unmodified, 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 THE AUTHOR OR CONTRIBUTORS 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/dev/cs/if_cs.c,v 1.19.2.1 2001/01/25 20:13:48 imp Exp $
 * $DragonFly: src/sys/dev/netif/cs/if_cs.c,v 1.23 2005/11/28 17:13:41 dillon Exp $
 */

/*
 * Device driver for Crystal Semiconductor CS8920 based ethernet
 *   adapters. By Maxim Bolotin and Oleg Sharoiko, 27-April-1997
 */

/*
#define	 CS_DEBUG 
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/thread2.h>

#include <sys/module.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <machine/resource.h>
#include <machine/clock.h>

#include <net/if.h>
#include <net/ifq_var.h>
#include <net/if_arp.h>
#include <net/if_media.h>
#include <net/ethernet.h>
#include <net/bpf.h>

#include "if_csreg.h"
#include "if_csvar.h"

#ifdef  CS_USE_64K_DMA
#define CS_DMA_BUFFER_SIZE 65536
#else
#define CS_DMA_BUFFER_SIZE 16384
#endif

static int	cs_recv_delay = 570;
SYSCTL_INT(_machdep, OID_AUTO, cs_recv_delay, CTLFLAG_RW, &cs_recv_delay, 0, "");

static void	cs_init(void *);
static int	cs_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
static void	cs_start(struct ifnet *);
static void	cs_stop(struct cs_softc *);
static void	cs_reset(struct cs_softc *);
static void	cs_watchdog(struct ifnet *);
static void	csintr(void *);

static int	cs_mediachange(struct ifnet *);
static void	cs_mediastatus(struct ifnet *, struct ifmediareq *);
static int      cs_mediaset(struct cs_softc *, int);

static void	cs_write_mbufs(struct cs_softc*, struct mbuf*);
static void	cs_xmit_buf(struct cs_softc*);
static int	cs_get_packet(struct cs_softc*);
static void	cs_setmode(struct cs_softc*);

static int	get_eeprom_data(device_t, int, int, int *);
static int	get_eeprom_cksum(int, int, int *);
static int	wait_eeprom_ready( struct cs_softc *);
static void	control_dc_dc(struct cs_softc *, int );
static int	send_test_pkt(struct cs_softc * );
static int	enable_tp(struct cs_softc *);
static int	enable_aui(struct cs_softc *);
static int	enable_bnc(struct cs_softc *);
static int      cs_duplex_auto(struct cs_softc *);

devclass_t cs_devclass;

DECLARE_DUMMY_MODULE(if_cs);

static int
get_eeprom_data(device_t dev, int off, int len, int *buffer)
{
	struct cs_softc *sc;
	int i;

	sc = device_get_softc(dev);

#ifdef CS_DEBUG
	device_printf(dev, "EEPROM data from %x for %x:\n", off, len);
#endif

	for (i=0;i<len;i++) {
		if (wait_eeprom_ready(sc) < 0) return -1;
		/* Send command to EEPROM to read */
		cs_writereg(sc->nic_addr, PP_EECMD, (off+i)|EEPROM_READ_CMD );
		if (wait_eeprom_ready(sc)<0)
			return -1;
		buffer[i] = cs_readreg (sc->nic_addr, PP_EEData);

#ifdef CS_DEBUG
		printf("%02x %02x ",(unsigned char)buffer[i],
					(unsigned char)buffer[i+1]);
#endif
	}

#ifdef CS_DEBUG
	printf("\n");
#endif

	return 0;
}

static int
get_eeprom_cksum(int off, int len, int *buffer)
{
	int i,cksum=0;

	for (i=0;i<len;i++)
		cksum+=buffer[i];
	cksum &= 0xffff;
	if (cksum==0)
		return 0;
	return -1;
}

static int
wait_eeprom_ready(struct cs_softc *sc)
{
	DELAY ( 30000 );	/* XXX should we do some checks here ? */
	return 0;
}

static void
control_dc_dc(struct cs_softc *sc, int on_not_off)
{
	unsigned int self_control = HCB1_ENBL;

	if (((sc->adapter_cnf & A_CNF_DC_DC_POLARITY)!=0) ^ on_not_off)
		self_control |= HCB1;
	else
		self_control &= ~HCB1;
	cs_writereg( sc->nic_addr, PP_SelfCTL, self_control );

	DELAY( 500000 );
}


static int
cs_duplex_auto(struct cs_softc *sc)
{
        int i, error=0;
        
        cs_writereg(sc->nic_addr, PP_AutoNegCTL,
                    RE_NEG_NOW | ALLOW_FDX | AUTO_NEG_ENABLE );
        for (i=0; cs_readreg(sc->nic_addr,PP_AutoNegST)&AUTO_NEG_BUSY; i++) {
                if (i > 40000) {
			if_printf(&sc->arpcom.ac_if, "full/half duplex "
				  "auto negotiation timeout\n");
			error = ETIMEDOUT;
                        break;
                }
                DELAY(1000);
        }
        DELAY( 1000000 );
	return error;
}

static int
enable_tp(struct cs_softc *sc)
{
	cs_writereg(sc->nic_addr, PP_LineCTL, sc->line_ctl & ~AUI_ONLY);
	control_dc_dc(sc, 0);
	DELAY( 150000 );

	if ((cs_readreg(sc->nic_addr, PP_LineST) & LINK_OK)==0) {
		if_printf(&sc->arpcom.ac_if, "failed to enable TP\n");
                return EINVAL;
	}

	return 0;
}

/*
 * XXX This was rewritten from Linux driver without any tests.
 */             
static int
send_test_pkt(struct cs_softc *sc)
{
	char test_packet[] = { 0,0,0,0,0,0, 0,0,0,0,0,0,
				0, 46,  /* A 46 in network order */
				0, 0,   /* DSAP=0 & SSAP=0 fields */
				0xf3, 0 /* Control (Test Req + P bit set) */ };
	int i;
	u_char ether_address_backup[ETHER_ADDR_LEN];

	for (i = 0; i < ETHER_ADDR_LEN; i++) {
		ether_address_backup[i] = sc->arpcom.ac_enaddr[i];
	}

	cs_writereg(sc->nic_addr, PP_LineCTL,
		cs_readreg(sc->nic_addr, PP_LineCTL) | SERIAL_TX_ON );
	bcopy(test_packet,
			sc->arpcom.ac_enaddr, ETHER_ADDR_LEN);
	bcopy(test_packet+ETHER_ADDR_LEN,
			sc->arpcom.ac_enaddr, ETHER_ADDR_LEN);
	outw(sc->nic_addr + TX_CMD_PORT, sc->send_cmd);
	outw(sc->nic_addr + TX_LEN_PORT, sizeof(test_packet));

	/* Wait for chip to allocate memory */
	DELAY(50000);
	if (!(cs_readreg(sc->nic_addr, PP_BusST) & READY_FOR_TX_NOW)) {
		for (i = 0; i < ETHER_ADDR_LEN; i++) {
			sc->arpcom.ac_enaddr[i] = ether_address_backup[i];
		}
		return 0;
	}

	outsw(sc->nic_addr + TX_FRAME_PORT, test_packet, sizeof(test_packet));

	DELAY(30000);

	if ((cs_readreg(sc->nic_addr,PP_TxEvent) & TX_SEND_OK_BITS) == TX_OK) {
		for (i = 0; i < ETHER_ADDR_LEN; i++) {
			sc->arpcom.ac_enaddr[i] = ether_address_backup[i];
		}
		return 1;
	}
	for (i = 0; i < ETHER_ADDR_LEN; i++) {
		sc->arpcom.ac_enaddr[i] = ether_address_backup[i];
	}
	return 0;
}

/*
 * XXX This was rewritten from Linux driver without any tests.
 */
static int
enable_aui(struct cs_softc *sc)
{
	control_dc_dc(sc, 0);
	cs_writereg(sc->nic_addr, PP_LineCTL,
		(sc->line_ctl & ~AUTO_AUI_10BASET) | AUI_ONLY);

	if (!send_test_pkt(sc)) {
		if_printf(&sc->arpcom.ac_if, "failed to enable AUI\n");
		return EINVAL;
        }
        return 0;
}

/*
 * XXX This was rewritten from Linux driver without any tests.
 */             
static int
enable_bnc(struct cs_softc *sc)
{
	control_dc_dc(sc, 1);
	cs_writereg(sc->nic_addr, PP_LineCTL,
		(sc->line_ctl & ~AUTO_AUI_10BASET) | AUI_ONLY);

	if (!send_test_pkt(sc)) {
		if_printf(&sc->arpcom.ac_if, "failed to enable BNC\n");
		return EINVAL;
        }
        return 0;
}

int
cs_cs89x0_probe(device_t dev)
{
	int i;
	int iobase;
	int error;

	u_long irq, junk;

	struct cs_softc *sc = device_get_softc(dev);

	unsigned rev_type = 0;
	char chip_revision;
	int eeprom_buff[CHKSUM_LEN];
	int chip_type, pp_isaint, pp_isadma;

	error = cs_alloc_port(dev, 0, CS_89x0_IO_PORTS);
	if (error)
		return (error);

	iobase=rman_get_start(sc->port_res);

	if ((inw(iobase+ADD_PORT) & ADD_MASK) != ADD_SIG) {
		/* Chip not detected. Let's try to reset it */
		if (bootverbose)
			device_printf(dev, "trying to reset the chip.\n");
		outw(iobase+ADD_PORT, PP_SelfCTL);
		i = inw(iobase+DATA_PORT);
		outw(iobase+ADD_PORT, PP_SelfCTL);
		outw(iobase+DATA_PORT, i | POWER_ON_RESET);
		if ((inw(iobase+ADD_PORT) & ADD_MASK) != ADD_SIG)
			return (ENXIO);
	}

	outw(iobase+ADD_PORT, PP_ChipID);
	if (inw(iobase+DATA_PORT) != CHIP_EISA_ID_SIG)
		return (ENXIO);

	rev_type = cs_readreg(iobase, PRODUCT_ID_ADD);
	chip_type = rev_type & ~REVISON_BITS;
	chip_revision = ((rev_type & REVISON_BITS) >> 8) + 'A';

	sc->nic_addr = iobase;
	sc->chip_type = chip_type;

	if(chip_type==CS8900) {
		pp_isaint = PP_CS8900_ISAINT;
		pp_isadma = PP_CS8900_ISADMA;
		sc->send_cmd = TX_CS8900_AFTER_ALL;
	} else {
		pp_isaint = PP_CS8920_ISAINT;
		pp_isadma = PP_CS8920_ISADMA;
		sc->send_cmd = TX_CS8920_AFTER_ALL;
	}

        /*
         * Clear some fields so that fail of EEPROM will left them clean
         */
        sc->auto_neg_cnf = 0;
        sc->adapter_cnf  = 0;
        sc->isa_config   = 0;
        
	/*
	 * If no interrupt specified (or "?"), use what the board tells us.
	 */
	error = bus_get_resource(dev, SYS_RES_IRQ, 0, &irq, &junk);

	/*
	 * Get data from EEPROM
	 */
	if((cs_readreg(iobase, PP_SelfST) & EEPROM_PRESENT) == 0) {
		device_printf(dev, "No EEPROM, assuming defaults.\n");
	} else {
		if (get_eeprom_data(dev, START_EEPROM_DATA, CHKSUM_LEN,
				    eeprom_buff)<0) {
			device_printf(dev, "EEPROM read failed, "
				"assuming defaults.\n");
		} else {
			if (get_eeprom_cksum(START_EEPROM_DATA,CHKSUM_LEN, eeprom_buff)<0) {
				device_printf(dev, "EEPROM cheksum bad, "
					"assuming defaults.\n");
			} else {
                                sc->auto_neg_cnf =
                                        eeprom_buff[AUTO_NEG_CNF_OFFSET/2];
                                sc->adapter_cnf =
                                        eeprom_buff[ADAPTER_CNF_OFFSET/2];
                                sc->isa_config =
                                        eeprom_buff[ISA_CNF_OFFSET/2];

                                for (i=0; i<ETHER_ADDR_LEN/2; i++) {
                                        sc->arpcom.ac_enaddr[i*2]=
                                                eeprom_buff[i];
                                        sc->arpcom.ac_enaddr[i*2+1]=
                                                eeprom_buff[i] >> 8;
                                }

                                /*
                                 * If no interrupt specified (or "?"),
                                 * use what the board tells us.
                                 */
				if (error) {
					irq = sc->isa_config & INT_NO_MASK;
                                        if (chip_type==CS8900) {
                                                switch(irq) {
						 case 0:
							irq=10;
							error=0;
							break;
						 case 1:
							irq=11;
							error=0;
							break;
						 case 2:
							irq=12;
							error=0;
							break;
						 case 3:
							irq=5;
							error=0;
							break;
						 default:
							device_printf(dev, "invalid irq in EEPROM.\n");
							error=EINVAL;
                                                }
					} else {
						if (irq>CS8920_NO_INTS) {
							device_printf(dev, "invalid irq in EEPROM.\n");
							error=EINVAL;
						} else {
							error=0;
						}
					}

					if (!error)
						bus_set_resource(dev, SYS_RES_IRQ, 0,
								irq, 1);
				}
			}
                }
        }

	if (!error) {
                if (chip_type == CS8900) {
			switch(irq) {
				case  5:
					irq = 3;
					break;
				case 10:
					irq = 0;
					break;
				case 11:
					irq = 1;
					break;
				case 12:
					irq = 2;
					break;
				default:
					error=EINVAL;
			}
                } else {
                        if (irq > CS8920_NO_INTS) {
                                error = EINVAL;
                        }
                }
	}

	if (!error) {
                cs_writereg(iobase, pp_isaint, irq);
	} else {
	       	device_printf(dev, "Unknown or invalid irq\n");
                return (ENXIO);
        }
        
        /*
         * Temporary disabled
         *
        if (drq>0)
		cs_writereg(iobase, pp_isadma, drq);
	else {
		device_printf(dev, "incorrect drq\n");
		return 0;
	}
        */

	if (bootverbose)
		 device_printf(dev, "CS89%c0%s rev %c media%s%s%s\n",
			chip_type==CS8900 ? '0' : '2',
			chip_type==CS8920M ? "M" : "",
			chip_revision,
			(sc->adapter_cnf & A_CNF_10B_T) ? " TP"  : "",
			(sc->adapter_cnf & A_CNF_AUI)   ? " AUI" : "",
			(sc->adapter_cnf & A_CNF_10B_2) ? " BNC" : "");

        if ((sc->adapter_cnf & A_CNF_EXTND_10B_2) &&
            (sc->adapter_cnf & A_CNF_LOW_RX_SQUELCH))
                sc->line_ctl = LOW_RX_SQUELCH;
        else
                sc->line_ctl = 0;

        
	return 0;
}

/*
 * Allocate a port resource with the given resource id.
 */
int cs_alloc_port(device_t dev, int rid, int size)
{
        struct cs_softc *sc = device_get_softc(dev);
        struct resource *res;

        res = bus_alloc_resource(dev, SYS_RES_IOPORT, &rid,
                                 0ul, ~0ul, size, RF_ACTIVE);
        if (res) {
                sc->port_rid = rid;
                sc->port_res = res;
                sc->port_used = size;
                return (0);
        } else {
                return (ENOENT);
        }
}

/*
 * Allocate a memory resource with the given resource id.
 */
int cs_alloc_memory(device_t dev, int rid, int size)
{
        struct cs_softc *sc = device_get_softc(dev);
        struct resource *res;

        res = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
                                 0ul, ~0ul, size, RF_ACTIVE);
        if (res) {
                sc->mem_rid = rid;
                sc->mem_res = res;
                sc->mem_used = size;
                return (0);
        } else {
                return (ENOENT);
        }
}

/*
 * Allocate an irq resource with the given resource id.
 */
int cs_alloc_irq(device_t dev, int rid, int flags)
{
        struct cs_softc *sc = device_get_softc(dev);
        struct resource *res;

        res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
	    (RF_ACTIVE | flags));
        if (res) {
                sc->irq_rid = rid;
                sc->irq_res = res;
                return (0);
        } else {
                return (ENOENT);
        }
}

/*
 * Release all resources
 */
void cs_release_resources(device_t dev)
{
        struct cs_softc *sc = device_get_softc(dev);

        if (sc->port_res) {
                bus_release_resource(dev, SYS_RES_IOPORT,
                                     sc->port_rid, sc->port_res);
                sc->port_res = 0;
        }
        if (sc->mem_res) {
                bus_release_resource(dev, SYS_RES_MEMORY,
                                     sc->mem_rid, sc->mem_res);
                sc->mem_res = 0;
        }
        if (sc->irq_res) {
                bus_release_resource(dev, SYS_RES_IRQ,
                                     sc->irq_rid, sc->irq_res);
                sc->irq_res = 0;
        }
}

/*
 * Install the interface into kernel networking data structures
 */
int
cs_attach(device_t dev)
{
        struct cs_softc *sc = device_get_softc(dev);
        int media = 0, error;
	struct ifnet *ifp = &sc->arpcom.ac_if;

	/*
	 * Initialize the media structures.
	 */
	ifmedia_init(&sc->media, 0, cs_mediachange, cs_mediastatus);

	KASSERT(sc->port_used > 0 || sc->mem_used > 0,
		("%s: either I/O port or I/O memory should be used",
		 device_get_nameunit(dev)));
	if (sc->port_used > 0)
		cs_alloc_port(dev, sc->port_rid, sc->port_used);
	if (sc->mem_used > 0)
		cs_alloc_memory(dev, sc->mem_rid, sc->mem_used);

	error = cs_alloc_irq(dev, sc->irq_rid, 0);
	if (error) {
		device_printf(dev, "Couldn't allocate irq");
		goto bad;
	}

	cs_stop(sc);

	ifp->if_softc=sc;
	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
	ifp->if_start=cs_start;
	ifp->if_ioctl=cs_ioctl;
	ifp->if_watchdog=cs_watchdog;
	ifp->if_init=cs_init;
	ifq_set_maxlen(&ifp->if_snd, IFQ_MAXLEN);
	ifq_set_ready(&ifp->if_snd);

#if 0
	/*
	 *  MIB DATA
	 */
	ifp->if_linkmib=&sc->mibdata;
	ifp->if_linkmiblen=sizeof sc->mibdata;
#endif

	ifp->if_flags=(IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST );

#if 0
	/*
	 * this code still in progress (DMA support)
	 */
	sc->recv_ring=malloc(CS_DMA_BUFFER_SIZE<<1, M_DEVBUF, M_WAITOK);
	if ((sc->recv_ring-(sc->recv_ring & 0x1FFFF))
	    < (128*1024-CS_DMA_BUFFER_SIZE))
	    sc->recv_ring+=16*1024;
#endif

	sc->buffer=malloc(ETHER_MAX_LEN-ETHER_CRC_LEN,M_DEVBUF,M_WAITOK);

	if (sc->adapter_cnf & A_CNF_10B_T) {
		ifmedia_add(&sc->media, IFM_ETHER|IFM_10_T, 0, NULL);
		if (sc->chip_type != CS8900) {
			ifmedia_add(&sc->media,
				IFM_ETHER|IFM_10_T|IFM_FDX, 0, NULL);
			ifmedia_add(&sc->media,
				IFM_ETHER|IFM_10_T|IFM_HDX, 0, NULL);
		}
	} 

	if (sc->adapter_cnf & A_CNF_10B_2)
		ifmedia_add(&sc->media, IFM_ETHER|IFM_10_2, 0, NULL);

	if (sc->adapter_cnf & A_CNF_AUI)
		ifmedia_add(&sc->media, IFM_ETHER|IFM_10_5, 0, NULL);

	if (sc->adapter_cnf & A_CNF_MEDIA)
		ifmedia_add(&sc->media, IFM_ETHER|IFM_AUTO, 0, NULL);

	/* Set default media from EEPROM */
	switch (sc->adapter_cnf & A_CNF_MEDIA_TYPE) {
	case A_CNF_MEDIA_AUTO:  media = IFM_ETHER|IFM_AUTO; break;
	case A_CNF_MEDIA_10B_T: media = IFM_ETHER|IFM_10_T; break;
	case A_CNF_MEDIA_10B_2: media = IFM_ETHER|IFM_10_2; break;
	case A_CNF_MEDIA_AUI:   media = IFM_ETHER|IFM_10_5; break;
	default: device_printf(dev, "adapter has no media\n");
	}
	ifmedia_set(&sc->media, media);
	cs_mediaset(sc, media);

	ether_ifattach(ifp, sc->arpcom.ac_enaddr, NULL);

	error = bus_setup_intr(dev, sc->irq_res, INTR_NETSAFE,
			       csintr, sc, &sc->irq_handle, 
			       ifp->if_serializer);
	if (error) {
		device_printf(dev, "Couldn't set up irq");
		ether_ifdetach(ifp);
		goto bad;
	}

	return 0;

bad:
	cs_detach(dev);
	return error;
}

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

	lwkt_serialize_enter(ifp->if_serializer);

	if (device_is_attached(dev)) {
		cs_stop(sc);
		ether_ifdetach(&sc->arpcom.ac_if);
	}
	if (sc->irq_handle != NULL)
		bus_teardown_intr(dev, sc->irq_res, sc->irq_handle);

#if 0
	/*
	 * this code still in progress (DMA support)
	 */
	if (sc->recv_ring != NULL)
		free(sc->recv_ring, M_DEVBUF);
#endif

	if (sc->buffer != NULL)
		free(sc->buffer, M_DEVBUF);
	cs_release_resources(dev);
	ifmedia_removeall(&sc->media);

	lwkt_serialize_exit(ifp->if_serializer);
	return 0;
}

/*
 * Initialize the board
 */
static void
cs_init(void *xsc)
{
	struct cs_softc *sc=(struct cs_softc *)xsc;
	struct ifnet *ifp = &sc->arpcom.ac_if;
	int i, rx_cfg;

	/*
	 * reset whatchdog timer
	 */
	ifp->if_timer=0;
	sc->buf_len = 0;

	/*
	 * Hardware initialization of cs
	 */

	/* Enable receiver and transmitter */
	cs_writereg(sc->nic_addr, PP_LineCTL,
		cs_readreg( sc->nic_addr, PP_LineCTL ) |
		SERIAL_RX_ON | SERIAL_TX_ON);

	/* Configure the receiver mode */
	cs_setmode(sc);

	/*
	 * This defines what type of frames will cause interrupts
	 * Bad frames should generate interrupts so that the driver
	 * could track statistics of discarded packets
	 */
        rx_cfg = RX_OK_ENBL | RX_CRC_ERROR_ENBL | RX_RUNT_ENBL |
		 RX_EXTRA_DATA_ENBL;
	if (sc->isa_config & STREAM_TRANSFER)
		rx_cfg |= RX_STREAM_ENBL;
	cs_writereg(sc->nic_addr, PP_RxCFG, rx_cfg);

	cs_writereg(sc->nic_addr, PP_TxCFG, TX_LOST_CRS_ENBL |
		    TX_SQE_ERROR_ENBL | TX_OK_ENBL | TX_LATE_COL_ENBL |
		    TX_JBR_ENBL | TX_ANY_COL_ENBL | TX_16_COL_ENBL);

	cs_writereg(sc->nic_addr, PP_BufCFG, READY_FOR_TX_ENBL |
		    RX_MISS_COUNT_OVRFLOW_ENBL | TX_COL_COUNT_OVRFLOW_ENBL |
		    TX_UNDERRUN_ENBL /*| RX_DMA_ENBL*/);

        /* Write MAC address into IA filter */
        for (i=0; i<ETHER_ADDR_LEN/2; i++)
                cs_writereg(sc->nic_addr, PP_IA+i*2,
                            sc->arpcom.ac_enaddr[i*2] |
                            (sc->arpcom.ac_enaddr[i*2+1] << 8) );

	/*
	 * Now enable everything
	 */
/*
#ifdef	CS_USE_64K_DMA
	cs_writereg(sc->nic_addr, PP_BusCTL, ENABLE_IRQ | RX_DMA_SIZE_64K);
        #else

        cs_writereg(sc->nic_addr, PP_BusCTL, ENABLE_IRQ);
#endif
*/
	cs_writereg(sc->nic_addr, PP_BusCTL, ENABLE_IRQ);
	
	/*
	 * Set running and clear output active flags
	 */
	sc->arpcom.ac_if.if_flags |= IFF_RUNNING;
	sc->arpcom.ac_if.if_flags &= ~IFF_OACTIVE;

	/*
	 * Start sending process
	 */
	cs_start(ifp);
}

/*
 * Get the packet from the board and send it to the upper layer
 * via ether_input().
 */
static int
cs_get_packet(struct cs_softc *sc)
{
	struct ifnet *ifp = &(sc->arpcom.ac_if);
	int iobase = sc->nic_addr, status, length;
	struct mbuf *m;

#ifdef CS_DEBUG
	int i;
#endif

	status = inw(iobase + RX_FRAME_PORT);
	length = inw(iobase + RX_FRAME_PORT);

#ifdef CS_DEBUG
	if_printf(ifp, "rcvd: stat %x, len %d\n", status, length);
#endif

	if (!(status & RX_OK)) {
#ifdef CS_DEBUG
		if_printf(ifp, "bad pkt stat %x\n", status);
#endif
		ifp->if_ierrors++;
		return -1;
	}

	MGETHDR(m, MB_DONTWAIT, MT_DATA);
	if (m==NULL)
		return -1;

	if (length > MHLEN) {
		MCLGET(m, MB_DONTWAIT);
		if (!(m->m_flags & M_EXT)) {
			m_freem(m);
			return -1;
		}
	}

	/* Initialize packet's header info */
	m->m_pkthdr.rcvif = ifp;
	m->m_pkthdr.len = length;
	m->m_len = length;

	/* Get the data */
	insw(iobase + RX_FRAME_PORT, m->m_data, (length+1)>>1);

#ifdef CS_DEBUG
	for (i=0;i<length;i++)
	     printf(" %02x",(unsigned char)*((char *)(m->m_data+i)));
	printf( "\n" );
#endif

	if (status & (RX_IA | RX_BROADCAST) || 
	    (ifp->if_flags & IFF_MULTICAST && status & RX_HASHED)) {
		ifp->if_input(ifp, m);

		ifp->if_ipackets++;

		if (length==ETHER_MAX_LEN-ETHER_CRC_LEN)
                        DELAY( cs_recv_delay );
	} else {
		m_freem(m);
	}

	return 0;
}

/*
 * Handle interrupts
 */
static void
csintr(void *arg)
{
	struct cs_softc *sc = (struct cs_softc*) arg;
	struct ifnet *ifp = &(sc->arpcom.ac_if);
	int status;

#ifdef CS_DEBUG
	if_printf(ifp, "Interrupt.\n");
#endif

	while ((status=cs_readword(sc->nic_addr, ISQ_PORT))) {

#ifdef CS_DEBUG
		if_printf(ifp, "from ISQ: %04x\n", status);
#endif

		switch (status & ISQ_EVENT_MASK) {
                case ISQ_RECEIVER_EVENT:
                        cs_get_packet(sc);
                        break;

                case ISQ_TRANSMITTER_EVENT:
                        if (status & TX_OK)
                                ifp->if_opackets++;
                        else
                                ifp->if_oerrors++;
                        ifp->if_flags &= ~IFF_OACTIVE;
                        ifp->if_timer = 0;
                        break;

                case ISQ_BUFFER_EVENT:
                        if (status & READY_FOR_TX) {
                                ifp->if_flags &= ~IFF_OACTIVE;
                                ifp->if_timer = 0;
                        }

                        if (status & TX_UNDERRUN) {
                                ifp->if_flags &= ~IFF_OACTIVE;
                                ifp->if_timer = 0;
                                ifp->if_oerrors++;
                        }
                        break;

                case ISQ_RX_MISS_EVENT:
                        ifp->if_ierrors+=(status>>6);
                        break;

                case ISQ_TX_COL_EVENT:
                        ifp->if_collisions+=(status>>6);
                        break;
                }
        }

        if (!(ifp->if_flags & IFF_OACTIVE)) {
                cs_start(ifp);
        }
}

/*
 * Save the data in buffer
 */

static void
cs_write_mbufs( struct cs_softc *sc, struct mbuf *m )
{
	int len;
	struct mbuf *mp;
	unsigned char *data, *buf;

	for (mp=m, buf=sc->buffer, sc->buf_len=0; mp != NULL; mp=mp->m_next) {
		len = mp->m_len;

		/*
		 * Ignore empty parts
		 */
		if (!len)
		continue;

		/*
		 * Find actual data address
		 */
		data = mtod(mp, caddr_t);

		bcopy((caddr_t) data, (caddr_t) buf, len);
		buf += len;
		sc->buf_len += len;
	}
}


static void
cs_xmit_buf( struct cs_softc *sc )
{
	outsw(sc->nic_addr+TX_FRAME_PORT, sc->buffer, (sc->buf_len+1)>>1);
	sc->buf_len = 0;
}

static void
cs_start(struct ifnet *ifp)
{
	int length;
	struct mbuf *m, *mp;
	struct cs_softc *sc = ifp->if_softc;

	for (;;) {
		if (sc->buf_len)
			length = sc->buf_len;
		else {
			m = ifq_dequeue(&ifp->if_snd, NULL);

			if (m==NULL) {
				return;
			}

			for (length=0, mp=m; mp != NULL; mp=mp->m_next)
				length += mp->m_len;

			/* Skip zero-length packets */
			if (length == 0) {
				m_freem(m);
				continue;
			}

			cs_write_mbufs(sc, m);

			BPF_MTAP(ifp, m);

			m_freem(m);
		}

		/*
		 * Issue a SEND command
		 */
		outw(sc->nic_addr+TX_CMD_PORT, sc->send_cmd);
		outw(sc->nic_addr+TX_LEN_PORT, length );

		/*
		 * If there's no free space in the buffer then leave
		 * this packet for the next time: indicate output active
		 * and return.
		 */
		if (!(cs_readreg(sc->nic_addr, PP_BusST) & READY_FOR_TX_NOW)) {
			ifp->if_timer = sc->buf_len;
			ifp->if_flags |= IFF_OACTIVE;
			return;
		}

               	cs_xmit_buf(sc);

		/*
		 * Set the watchdog timer in case we never hear
		 * from board again. (I don't know about correct
		 * value for this timeout)
		 */
		ifp->if_timer = length;

		ifp->if_flags |= IFF_OACTIVE;
		return;
	}
}

/*
 * Stop everything on the interface
 */
static void
cs_stop(struct cs_softc *sc)
{
	cs_writereg(sc->nic_addr, PP_RxCFG, 0);
	cs_writereg(sc->nic_addr, PP_TxCFG, 0);
	cs_writereg(sc->nic_addr, PP_BufCFG, 0);
	cs_writereg(sc->nic_addr, PP_BusCTL, 0);

	sc->arpcom.ac_if.if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
	sc->arpcom.ac_if.if_timer = 0;
}

/*
 * Reset the interface
 */
static void
cs_reset(struct cs_softc *sc)
{
	cs_stop(sc);
	cs_init(sc);
}

static void
cs_setmode(struct cs_softc *sc)
{
	struct ifnet *ifp = &(sc->arpcom.ac_if);
	int rx_ctl;

	/* Stop the receiver while changing filters */
	cs_writereg(sc->nic_addr, PP_LineCTL, 
			cs_readreg(sc->nic_addr, PP_LineCTL) & ~SERIAL_RX_ON);

	if (ifp->if_flags & IFF_PROMISC) {
		/* Turn on promiscuous mode. */
		rx_ctl = RX_OK_ACCEPT | RX_PROM_ACCEPT;
	} else {
		if (ifp->if_flags & IFF_MULTICAST) {
			/* Allow receiving frames with multicast addresses */
			rx_ctl = RX_IA_ACCEPT | RX_BROADCAST_ACCEPT |
				 RX_OK_ACCEPT | RX_MULTCAST_ACCEPT;
			/*
			 * Here the reconfiguration of chip's multicast
			 * filters should be done but I've no idea about
			 * hash transformation in this chip. If you can
			 * add this code or describe me the transformation
			 * I'd be very glad.
			 */
		} else {
			/*
			 * Receive only good frames addressed for us and
			 * good broadcasts.
			 */
			rx_ctl = RX_IA_ACCEPT | RX_BROADCAST_ACCEPT |
				 RX_OK_ACCEPT;
		}
	}

	/* Set up the filter */
	cs_writereg(sc->nic_addr, PP_RxCTL, RX_DEF_ACCEPT | rx_ctl);

	/* Turn on receiver */
	cs_writereg(sc->nic_addr, PP_LineCTL,
			cs_readreg(sc->nic_addr, PP_LineCTL) | SERIAL_RX_ON);
}

static int
cs_ioctl(register struct ifnet *ifp, u_long command, caddr_t data,
    struct ucred *cr)
{
	struct cs_softc *sc=ifp->if_softc;
	struct ifreq *ifr = (struct ifreq *)data;
	int error=0;

#ifdef CS_DEBUG
	if_printf(ifp, "ioctl(%lx)\n", command);
#endif

	switch (command) {
	case SIOCSIFFLAGS:
		/*
		 * Switch interface state between "running" and
		 * "stopped", reflecting the UP flag.
                 */
                if (sc->arpcom.ac_if.if_flags & IFF_UP) {
                        if ((sc->arpcom.ac_if.if_flags & IFF_RUNNING)==0) {
                                cs_init(sc);
                        }
                } else {
                        if ((sc->arpcom.ac_if.if_flags & IFF_RUNNING)!=0) {
                                cs_stop(sc);
                        }
		}
		/*
		 * Promiscuous and/or multicast flags may have changed,
		 * so reprogram the multicast filter and/or receive mode.
		 *
		 * See note about multicasts in cs_setmode
		 */
		cs_setmode(sc);
		break;

	case SIOCADDMULTI:
	case SIOCDELMULTI:
	    /*
	     * Multicast list has changed; set the hardware filter
	     * accordingly.
	     *
	     * See note about multicasts in cs_setmode
	     */
	    cs_setmode(sc);
	    error = 0;
	    break;

        case SIOCSIFMEDIA:
        case SIOCGIFMEDIA:
                error = ifmedia_ioctl(ifp, ifr, &sc->media, command);
                break;
	default:
		error = ether_ioctl(ifp, command, data);
		break;
        }

	return error;
}

/*
 * Device timeout/watchdog routine. Entered if the device neglects to
 * generate an interrupt after a transmit has been started on it.
 */
static void
cs_watchdog(struct ifnet *ifp)
{
	struct cs_softc *sc = ifp->if_softc;

	ifp->if_oerrors++;
	log(LOG_ERR, "%s: device timeout\n", ifp->if_xname);

	/* Reset the interface */
	if (ifp->if_flags & IFF_UP)
		cs_reset(sc);
	else
		cs_stop(sc);
}

static int
cs_mediachange(struct ifnet *ifp)
{
	struct cs_softc *sc = ifp->if_softc;
	struct ifmedia *ifm = &sc->media;

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

	return cs_mediaset(sc, ifm->ifm_media);
}

static void
cs_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
{
	int line_status;
	struct cs_softc *sc = ifp->if_softc;

	ifmr->ifm_active = IFM_ETHER;
	line_status = cs_readreg(sc->nic_addr, PP_LineST);
	if (line_status & TENBASET_ON) {
		ifmr->ifm_active |= IFM_10_T;
		if (sc->chip_type != CS8900) {
			if (cs_readreg(sc->nic_addr, PP_AutoNegST) & FDX_ACTIVE)
				ifmr->ifm_active |= IFM_FDX;
			if (cs_readreg(sc->nic_addr, PP_AutoNegST) & HDX_ACTIVE)
				ifmr->ifm_active |= IFM_HDX;
		}
		ifmr->ifm_status = IFM_AVALID;
		if (line_status & LINK_OK)
			ifmr->ifm_status |= IFM_ACTIVE;
	} else {
		if (line_status & AUI_ON) {
			cs_writereg(sc->nic_addr, PP_SelfCTL,
				    cs_readreg(sc->nic_addr, PP_SelfCTL) |
				    HCB1_ENBL);
			if (((sc->adapter_cnf & A_CNF_DC_DC_POLARITY)!=0)^
			    (cs_readreg(sc->nic_addr, PP_SelfCTL)&HCB1))
				ifmr->ifm_active |= IFM_10_2;
			else
				ifmr->ifm_active |= IFM_10_5;
		}
	}
}

static int
cs_mediaset(struct cs_softc *sc, int media)
{
        int error;

	/* Stop the receiver & transmitter */
	cs_writereg(sc->nic_addr, PP_LineCTL,
                    cs_readreg(sc->nic_addr, PP_LineCTL) &
		    ~(SERIAL_RX_ON | SERIAL_TX_ON));

#ifdef CS_DEBUG
	if_printf(&sc->arpcom.ac_if, "cs_setmedia(%x)\n", media);
#endif

	switch (IFM_SUBTYPE(media)) {
	default:
	case IFM_AUTO:
		if ((error=enable_tp(sc))==0)
			error = cs_duplex_auto(sc);
		else if ((error=enable_bnc(sc)) != 0)
			error = enable_aui(sc);
		break;
	case IFM_10_T:
		if ((error=enable_tp(sc)) != 0)
			break;
		if (media & IFM_FDX)
			cs_duplex_full(sc);
		else if (media & IFM_HDX)
			cs_duplex_half(sc);
		else
			error = cs_duplex_auto(sc);
		break;
	case IFM_10_2:
		error = enable_bnc(sc);
		break;
	case IFM_10_5:
		error = enable_aui(sc);
		break;
	}

	/*
	 * Turn the transmitter & receiver back on
	 */
	cs_writereg(sc->nic_addr, PP_LineCTL,
		    cs_readreg( sc->nic_addr, PP_LineCTL ) |
		    SERIAL_RX_ON | SERIAL_TX_ON); 

	return error;
}