xref: /src/sys/dev/ic/seeq8005.c

/* $NetBSD: seeq8005.c,v 1.63 2019/05/23 13:10:51 msaitoh Exp $ */

/*
 * Copyright (c) 2000, 2001 Ben Harris
 * Copyright (c) 1995-1998 Mark Brinicombe
 * 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 Mark Brinicombe
 *	for the NetBSD Project.
 * 4. The name of the company nor the name of the author may be used to
 *    endorse or promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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.
 */
/*
 * seeq8005.c - SEEQ 8005 device driver
 */
/*
 * This driver currently supports the following chips:
 * SEEQ 8005 Advanced Ethernet Data Link Controller
 * SEEQ 80C04 Ethernet Data Link Controller
 * SEEQ 80C04A AutoDUPLEX CMOS Ethernet Data Link Controller
 */
/*
 * More information on the 8004 and 8005 AEDLC controllers can be found in
 * the SEEQ Technology Inc 1992 Data Comm Devices data book.
 *
 * This data book may no longer be available as these are rather old chips
 * (1991 - 1993)
 */
/*
 * This driver is based on the arm32 ea(4) driver, hence the names of many
 * of the functions.
 */
/*
 * Bugs/possible improvements:
 *	- Does not currently support DMA
 *	- Does not transmit multiple packets in one go
 *	- Does not support 8-bit busses
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: seeq8005.c,v 1.63 2019/05/23 13:10:51 msaitoh Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/endian.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <sys/device.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/if_ether.h>
#include <net/if_media.h>
#include <net/bpf.h>

#include <sys/rndsource.h>

#include <sys/bus.h>
#include <sys/intr.h>

#include <dev/ic/seeq8005reg.h>
#include <dev/ic/seeq8005var.h>

/*#define SEEQ_DEBUG*/

/* for debugging convenience */
#ifdef SEEQ8005_DEBUG
#define SEEQ_DEBUG_MISC		1
#define SEEQ_DEBUG_TX		2
#define SEEQ_DEBUG_RX		4
#define SEEQ_DEBUG_PKT		8
#define SEEQ_DEBUG_TXINT	16
#define SEEQ_DEBUG_RXINT	32
int seeq8005_debug = 0;
#define DPRINTF(f, x) { if (seeq8005_debug & (f)) printf x; }
#else
#define DPRINTF(f, x)
#endif

#ifndef EA_TX_BUFFER_SIZE
#define EA_TX_BUFFER_SIZE		0x800		/* (> ETHER_MAX_LEN) */
#endif
#ifndef EA_TX_BUFFER_COUNT
#define EA_TX_BUFFER_COUNT		1		/* (> 0) */
#endif

#define SEEQ_READ16(sc, iot, ioh, reg)					\
	((sc)->sc_flags & SF_8BIT ?					\
	    (bus_space_read_1((iot), (ioh), (reg)) |			\
	     (bus_space_read_1((iot), (ioh), (reg) + 1) << 8)) :	\
	    (bus_space_read_2((iot), (ioh), (reg))))

#define SEEQ_WRITE16(sc, iot, ioh, reg, val) do {			\
	if ((sc)->sc_flags & SF_8BIT) {					\
		bus_space_write_1((iot), (ioh), (reg), (val) & 0xff);	\
		bus_space_write_1((iot), (ioh), (reg) + 1, (val) >> 8);	\
	} else								\
		bus_space_write_2((iot), (ioh), (reg), (val));		\
} while (/*CONSTCOND*/0)

/*
 * prototypes
 */

static int ea_init(struct ifnet *);
static int ea_ioctl(struct ifnet *, u_long, void *);
static void ea_start(struct ifnet *);
static void ea_watchdog(struct ifnet *);
static void ea_chipreset(struct seeq8005_softc *);
static void ea_ramtest(struct seeq8005_softc *);
static int ea_stoptx(struct seeq8005_softc *);
static int ea_stoprx(struct seeq8005_softc *);
static void ea_stop(struct ifnet *, int);
static void ea_await_fifo_empty(struct seeq8005_softc *);
static void ea_await_fifo_full(struct seeq8005_softc *);
static void ea_writebuf(struct seeq8005_softc *, u_char *, int, size_t);
static void ea_readbuf(struct seeq8005_softc *, u_char *, int, size_t);
static void ea_select_buffer(struct seeq8005_softc *, int);
static void ea_set_address(struct seeq8005_softc *, int, const uint8_t *);
static void ea_read(struct seeq8005_softc *, int, int);
static struct mbuf *ea_get(struct seeq8005_softc *, int, int, struct ifnet *);
static void ea_txint(struct seeq8005_softc *);
static void ea_rxint(struct seeq8005_softc *);
static void ea_txpacket(struct seeq8005_softc *);
static int ea_writembuf(struct seeq8005_softc *, struct mbuf *, int);
static void ea_mc_reset(struct seeq8005_softc *);
static void ea_mc_reset_8004(struct seeq8005_softc *);
static void ea_mc_reset_8005(struct seeq8005_softc *);
static int ea_mediachange(struct ifnet *);
static void ea_mediastatus(struct ifnet *, struct ifmediareq *);

static u_char* padbuf = NULL;


/*
 * Attach chip.
 */

void
seeq8005_attach(struct seeq8005_softc *sc, const uint8_t *myaddr, int *media,
    int nmedia, int defmedia)
{
	device_t dev = sc->sc_dev;
	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	u_int id;

	KASSERT(myaddr != NULL);
	printf(" address %s", ether_sprintf(myaddr));

	/* Stop the board. */

	ea_chipreset(sc);

	/* Work out data bus width. */
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_RX_PTR, 0x1234);
	if (SEEQ_READ16(sc, iot, ioh, SEEQ_RX_PTR) != 0x1234) {
		/* Try 8-bit mode */
		sc->sc_flags |= SF_8BIT;
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_RX_PTR, 0x1234);
		if (SEEQ_READ16(sc, iot, ioh, SEEQ_RX_PTR) != 0x1234) {
			aprint_normal("\n");
			aprint_error_dev(dev,
			    "Cannot determine data bus width\n");
			return;
		}
	}

	printf(", %d-bit", sc->sc_flags & SF_8BIT ? 8 : 16);

	/* Get the product ID */

	ea_select_buffer(sc, SEEQ_BUFCODE_PRODUCTID);
	id = SEEQ_READ16(sc, sc->sc_iot, sc->sc_ioh, SEEQ_BUFWIN);

	switch (id & SEEQ_PRODUCTID_MASK) {
	case SEEQ_PRODUCTID_8004:
		sc->sc_variant = SEEQ_8004;
		switch (id & SEEQ_PRODUCTID_REV_MASK) {
		case SEEQ_PRODUCTID_REV_80C04:
			printf(", SEEQ 80C04\n");
			break;
		case SEEQ_PRODUCTID_REV_80C04A:
			printf(", SEEQ 80C04A\n");
			break;
		default:
			/* Unknown SEEQ 8004 variants */
			printf(", SEEQ 8004 rev %x\n",
			    id & SEEQ_PRODUCTID_REV_MASK);
			break;
		}
		break;
	default:	/* XXX */
		sc->sc_variant = SEEQ_8005;
		printf(", SEEQ 8005\n");
		break;
	}

	/* Both the 8004 and 8005 are designed for 64K Buffer memory */
	sc->sc_buffersize = SEEQ_MAX_BUFFER_SIZE;

	/*
	 * Set up tx and rx buffers.
	 *
	 * We set aside EA_TX_BUFFER_SIZE * EA_TX_BUFFER_COUNT for TX
	 * buffers and the rest for RX buffers
	 */
	sc->sc_tx_bufs = EA_TX_BUFFER_COUNT;
	sc->sc_tx_bufsize = sc->sc_tx_bufs * EA_TX_BUFFER_SIZE;
	sc->sc_rx_bufsize = sc->sc_buffersize - sc->sc_tx_bufsize;
	sc->sc_enabled = 0;

	/* Test the RAM */
	ea_ramtest(sc);

	printf("%s: %dKB packet memory, txbuf=%dKB (%d buffers), rxbuf=%dKB",
	    device_xname(dev), sc->sc_buffersize >> 10,
	    sc->sc_tx_bufsize >> 10, sc->sc_tx_bufs, sc->sc_rx_bufsize >> 10);

	if (padbuf == NULL) {
		padbuf = malloc(ETHER_MIN_LEN - ETHER_CRC_LEN, M_DEVBUF,
		    M_ZERO | M_NOWAIT);
		if (padbuf == NULL) {
			aprint_error_dev(dev, "can't allocate pad buffer\n");
			return;
		}
	}

	/* Initialise ifnet structure. */

	strlcpy(ifp->if_xname, device_xname(dev), IFNAMSIZ);
	ifp->if_softc = sc;
	ifp->if_start = ea_start;
	ifp->if_ioctl = ea_ioctl;
	ifp->if_init = ea_init;
	ifp->if_stop = ea_stop;
	ifp->if_watchdog = ea_watchdog;
	ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST;
	if (sc->sc_variant == SEEQ_8004)
		ifp->if_flags |= IFF_SIMPLEX;
	IFQ_SET_READY(&ifp->if_snd);

	/* Initialize media goo. */
	ifmedia_init(&sc->sc_media, 0, ea_mediachange, ea_mediastatus);
	if (media != NULL) {
		int i;

		for (i = 0; i < nmedia; i++)
			ifmedia_add(&sc->sc_media, media[i], 0, NULL);
		ifmedia_set(&sc->sc_media, defmedia);
	} else {
		ifmedia_add(&sc->sc_media, IFM_ETHER | IFM_MANUAL, 0, NULL);
		ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_MANUAL);
	}

	/* We can support 802.1Q VLAN-sized frames. */
	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;

	/* Now we can attach the interface. */

	if_attach(ifp);
	ether_ifattach(ifp, myaddr);

	printf("\n");

	/* After \n because it can print a line of its own. */
	rnd_attach_source(&sc->rnd_source, device_xname(dev),
	    RND_TYPE_NET, RND_FLAG_DEFAULT);
}

/*
 * Media change callback.
 */
static int
ea_mediachange(struct ifnet *ifp)
{
	struct seeq8005_softc *sc = ifp->if_softc;

	if (sc->sc_mediachange)
		return (*sc->sc_mediachange)(sc);
	return EINVAL;
}

/*
 * Media status callback.
 */
static void
ea_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
{
	struct seeq8005_softc *sc = ifp->if_softc;

	if (sc->sc_enabled == 0) {
		ifmr->ifm_active = IFM_ETHER | IFM_NONE;
		ifmr->ifm_status = 0;
		return;
	}

	if (sc->sc_mediastatus)
		(*sc->sc_mediastatus)(sc, ifmr);
}

/*
 * Test the RAM on the ethernet card.
 */

void
ea_ramtest(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int loop;
	u_int sum = 0;

	/*
	 * Test the buffer memory on the board.
	 * Write simple pattens to it and read them back.
	 */

	/* Set up the whole buffer RAM for writing */

	ea_select_buffer(sc, SEEQ_BUFCODE_TX_EAP);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, (SEEQ_MAX_BUFFER_SIZE >> 8) - 1);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_TX_PTR, 0x0000);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_RX_PTR, SEEQ_MAX_BUFFER_SIZE - 2);

#define SEEQ_RAMTEST_LOOP(value)					\
do {									\
	/* Set the write start address and write a pattern */		\
	ea_writebuf(sc, NULL, 0x0000, 0);				\
	for (loop = 0; loop < SEEQ_MAX_BUFFER_SIZE; loop += 2)		\
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, (value));	\
									\
	/* Set the read start address and verify the pattern */		\
	ea_readbuf(sc, NULL, 0x0000, 0);				\
	for (loop = 0; loop < SEEQ_MAX_BUFFER_SIZE; loop += 2)		\
		if (SEEQ_READ16(sc, iot, ioh, SEEQ_BUFWIN) != (value))	\
			++sum;						\
} while (/*CONSTCOND*/0)

	SEEQ_RAMTEST_LOOP(loop);
	SEEQ_RAMTEST_LOOP(loop ^ (SEEQ_MAX_BUFFER_SIZE - 1));
	SEEQ_RAMTEST_LOOP(0xaa55);
	SEEQ_RAMTEST_LOOP(0x55aa);

	/* Report */

	if (sum > 0)
		aprint_error_dev(sc->sc_dev,
		    "buffer RAM failed self test, %d faults\n", sum);
}


/*
 * Stop the tx interface.
 *
 * Returns 0 if the tx was already stopped or 1 if it was active
 */

static int
ea_stoptx(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int timeout;
	int status;

	DPRINTF(SEEQ_DEBUG_TX, ("ea_stoptx()\n"));

	sc->sc_enabled = 0;

	status = SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS);
	if (!(status & SEEQ_STATUS_TX_ON))
		return 0;

	/* Stop any tx and wait for confirmation */
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
	    sc->sc_command | SEEQ_CMD_TX_OFF);

	timeout = 20000;
	do {
		status = SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS);
		delay(1);
	} while ((status & SEEQ_STATUS_TX_ON) && --timeout > 0);
	if (timeout == 0)
		log(LOG_ERR, "%s: timeout waiting for tx termination\n",
		    device_xname(sc->sc_dev));

	/* Clear any pending tx interrupt */
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
		   sc->sc_command | SEEQ_CMD_TX_INTACK);
	return 1;
}


/*
 * Stop the rx interface.
 *
 * Returns 0 if the tx was already stopped or 1 if it was active
 */

static int
ea_stoprx(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int timeout;
	int status;

	DPRINTF(SEEQ_DEBUG_RX, ("ea_stoprx()\n"));

	status = SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS);
	if (!(status & SEEQ_STATUS_RX_ON))
		return 0;

	/* Stop any rx and wait for confirmation */

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
			  sc->sc_command | SEEQ_CMD_RX_OFF);

	timeout = 20000;
	do {
		status = SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS);
		delay(1);
	} while ((status & SEEQ_STATUS_RX_ON) && --timeout > 0);
	if (timeout == 0)
		log(LOG_ERR, "%s: timeout waiting for rx termination\n",
		    device_xname(sc->sc_dev));

	/* Clear any pending rx interrupt */

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
		   sc->sc_command | SEEQ_CMD_RX_INTACK);
	return 1;
}


/*
 * Stop interface.
 * Stop all IO and shut the interface down
 */

/* ARGSUSED */
static void
ea_stop(struct ifnet *ifp, int disable)
{
	struct seeq8005_softc *sc = ifp->if_softc;
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;

	DPRINTF(SEEQ_DEBUG_MISC, ("ea_stop()\n"));

	/* Stop all IO */
	ea_stoptx(sc);
	ea_stoprx(sc);

	/* Disable rx and tx interrupts */
	sc->sc_command &= ~(SEEQ_CMD_RX_INTEN | SEEQ_CMD_TX_INTEN);

	/* Clear any pending interrupts */
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
	    sc->sc_command | SEEQ_CMD_RX_INTACK | SEEQ_CMD_TX_INTACK |
	    SEEQ_CMD_DMA_INTACK | SEEQ_CMD_BW_INTACK);

	if (sc->sc_variant == SEEQ_8004) {
		/* Put the chip to sleep */
		ea_select_buffer(sc, SEEQ_BUFCODE_CONFIG3);
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN,
		    sc->sc_config3 | SEEQ_CFG3_SLEEP);
	}

	/* Cancel any watchdog timer */
	sc->sc_ethercom.ec_if.if_timer = 0;
}


/*
 * Reset the chip
 * Following this the software registers are reset
 */

static void
ea_chipreset(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;

	DPRINTF(SEEQ_DEBUG_MISC, ("ea_chipreset()\n"));

	/* Reset the controller. Min of 4us delay here */

	/*
	 * This can be called before we know whether the chip is in 8- or
	 * 16-bit mode, so we do a reset in both modes.  The 16-bit reset is
	 * harmless in 8-bit mode, so we do that second.
	 */

	/* In 16-bit mode, this will munge the PreamSelect bit. */
	bus_space_write_1(iot, ioh, SEEQ_CONFIG2 + 1, SEEQ_CFG2_RESET >> 8);
	delay(4);
	/* In 8-bit mode, this will zero the bottom half of config reg 2. */
	bus_space_write_2(iot, ioh, SEEQ_CONFIG2, SEEQ_CFG2_RESET);
	delay(4);

	sc->sc_command = 0;
	sc->sc_config1 = 0;
	sc->sc_config2 = 0;
	sc->sc_config3 = 0;
}


/*
 * If the DMA FIFO's in write mode, wait for it to empty.  Needed when
 * switching the FIFO from write to read.  We also use it when changing
 * the address for writes.
 */
static void
ea_await_fifo_empty(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int timeout;

	timeout = 20000;
	if ((SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS) &
	     SEEQ_STATUS_FIFO_DIR) != 0)
		return; /* FIFO is reading anyway. */
	while (--timeout > 0)
		if (SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS) &
		    SEEQ_STATUS_FIFO_EMPTY)
			return;
	log(LOG_ERR, "%s: DMA FIFO failed to empty\n", device_xname(sc->sc_dev));
}

/*
 * Wait for the DMA FIFO to fill before reading from it.
 */
static void
ea_await_fifo_full(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int timeout;

	timeout = 20000;
	while (--timeout > 0)
		if (SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS) &
		    SEEQ_STATUS_FIFO_FULL)
			return;
	log(LOG_ERR, "%s: DMA FIFO failed to fill\n", device_xname(sc->sc_dev));
}

/*
 * write to the buffer memory on the interface
 *
 * The buffer address is set to ADDR.
 * If len != 0 then data is copied from the address starting at buf
 * to the interface buffer.
 * BUF must be usable as a uint16_t *.
 * If LEN is odd, it must be safe to overwrite one extra byte.
 */

static void
ea_writebuf(struct seeq8005_softc *sc, u_char *buf, int addr, size_t len)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;

	DPRINTF(SEEQ_DEBUG_MISC, ("writebuf: st=%04x\n",
	    SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS)));

#ifdef DIAGNOSTIC
	if (__predict_false(!ALIGNED_POINTER(buf, uint16_t)))
		panic("%s: unaligned writebuf", device_xname(sc->sc_dev));
	if (__predict_false(addr >= SEEQ_MAX_BUFFER_SIZE))
		panic("%s: writebuf out of range", device_xname(sc->sc_dev));
#endif

	if (addr != -1) {
		ea_await_fifo_empty(sc);

		ea_select_buffer(sc, SEEQ_BUFCODE_LOCAL_MEM);
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
		    sc->sc_command | SEEQ_CMD_FIFO_WRITE);

		ea_await_fifo_empty(sc);

		SEEQ_WRITE16(sc, iot, ioh, SEEQ_DMA_ADDR, addr);
	}

	if (len > 0) {
		if (sc->sc_flags & SF_8BIT)
			bus_space_write_multi_1(iot, ioh, SEEQ_BUFWIN,
			    (uint8_t *)buf, len);
		else
			bus_space_write_multi_2(iot, ioh, SEEQ_BUFWIN,
			    /* LINTED: alignment checked above */
			    (uint16_t *)buf, len / 2);
	}
	if (!(sc->sc_flags & SF_8BIT) && len % 2) {
		/* Write the last byte */
		bus_space_write_2(iot, ioh, SEEQ_BUFWIN, buf[len - 1]);
	}
	/* Leave FIFO to empty in the background */
}


/*
 * read from the buffer memory on the interface
 *
 * The buffer address is set to ADDR.
 * If len != 0 then data is copied from the interface buffer to the
 * address starting at buf.
 * BUF must be usable as a uint16_t *.
 * If LEN is odd, it must be safe to overwrite one extra byte.
 */

static void
ea_readbuf(struct seeq8005_softc *sc, u_char *buf, int addr, size_t len)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int runup;

	DPRINTF(SEEQ_DEBUG_MISC, ("readbuf: st=%04x addr=%04x len=%d\n",
	    SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS), addr, len));

#ifdef DIAGNOSTIC
	if (__predict_false(!ALIGNED_POINTER(buf, uint16_t)))
		panic("%s: unaligned readbuf", device_xname(sc->sc_dev));
	if (__predict_false(addr >= SEEQ_MAX_BUFFER_SIZE))
		panic("%s: readbuf out of range", device_xname(sc->sc_dev));
#endif

	if (addr != -1) {
		/*
		 * SEEQ 80C04 bug:
		 * Starting reading from certain addresses seems to cause
		 * us to get bogus results, so we avoid them.
		 */
		runup = 0;
		if (sc->sc_variant == SEEQ_8004 &&
		    ((addr & 0x00ff) == 0x00ea ||
		     (addr & 0x00ff) == 0x00ee ||
		     (addr & 0x00ff) == 0x00f0))
			runup = (addr & 0x00ff) - 0x00e8;

		ea_await_fifo_empty(sc);

		ea_select_buffer(sc, SEEQ_BUFCODE_LOCAL_MEM);

		/*
		 * 80C04 bug workaround.  I found this in the old arm32 "eb"
		 * driver.  I've no idea what it does, but it seems to stop
		 * the chip mangling data so often.
		 */
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
		    sc->sc_command | SEEQ_CMD_FIFO_WRITE);
		ea_await_fifo_empty(sc);

		SEEQ_WRITE16(sc, iot, ioh, SEEQ_DMA_ADDR, addr - runup);
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
		    sc->sc_command | SEEQ_CMD_FIFO_READ);

		ea_await_fifo_full(sc);
		while (runup > 0) {
			/* LINTED: Reading a volatile _does_ have an effect */
			(void)SEEQ_READ16(sc, iot, ioh, SEEQ_BUFWIN);
			runup -= 2;
		}
	}

	if (len > 0) {
		if (sc->sc_flags & SF_8BIT)
			bus_space_read_multi_1(iot, ioh, SEEQ_BUFWIN,
			    (uint8_t *)buf, len);
		else
			bus_space_read_multi_2(iot, ioh, SEEQ_BUFWIN,
			    /* LINTED: pointer alignment checked above */
			    (uint16_t *)buf, len / 2);
	}
	if (!(sc->sc_flags & SF_8BIT) && len % 2) {
		/* Read the last byte */
		buf[len - 1] = bus_space_read_2(iot, ioh, SEEQ_BUFWIN);
	}
}

static void
ea_select_buffer(struct seeq8005_softc *sc, int bufcode)
{

	SEEQ_WRITE16(sc, sc->sc_iot, sc->sc_ioh, SEEQ_CONFIG1,
			  sc->sc_config1 | bufcode);
}

/* Must be called at splnet */
static void
ea_set_address(struct seeq8005_softc *sc, int which, const uint8_t *ea)
{
	int i;

	ea_select_buffer(sc, SEEQ_BUFCODE_STATION_ADDR0 + which);
	for (i = 0; i < ETHER_ADDR_LEN; ++i)
		SEEQ_WRITE16(sc, sc->sc_iot, sc->sc_ioh, SEEQ_BUFWIN, ea[i]);
}

/*
 * Initialize interface.
 *
 * This should leave the interface in a state for packet reception and
 * transmission.
 */

static int
ea_init(struct ifnet *ifp)
{
	struct seeq8005_softc *sc = ifp->if_softc;
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int s;

	DPRINTF(SEEQ_DEBUG_MISC, ("ea_init()\n"));

	s = splnet();

	/* First, reset the board. */

	ea_chipreset(sc);

	/* Set up defaults for the registers */

	sc->sc_command = 0;
	sc->sc_config1 = 0;
#if BYTE_ORDER == BIG_ENDIAN
	sc->sc_config2 = SEEQ_CFG2_BYTESWAP;
#else
	sc->sc_config2 = 0;
#endif
	sc->sc_config3 = 0;

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND, sc->sc_command);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG1, sc->sc_config1);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG2, sc->sc_config2);
	if (sc->sc_variant == SEEQ_8004) {
		ea_select_buffer(sc, SEEQ_BUFCODE_CONFIG3);
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, sc->sc_config3);
	}

	/* Write the station address - the receiver must be off */
	ea_set_address(sc, 0, (const uint8_t *)CLLADDR(ifp->if_sadl));

	/* Split board memory into Rx and Tx. */
	ea_select_buffer(sc, SEEQ_BUFCODE_TX_EAP);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, (sc->sc_tx_bufsize>> 8) - 1);

	if (sc->sc_variant == SEEQ_8004) {
		/* Make the interface IFF_SIMPLEX. */
		sc->sc_config2 |= SEEQ_CFG2_RX_TX_DISABLE;
		/* Enable reception of long packets (for vlan(4)). */
		sc->sc_config2 |= SEEQ_CFG2_PASS_LONGSHORT;
	}

	/* Configure rx. */
	ea_mc_reset(sc);
	if (ifp->if_flags & IFF_PROMISC)
		sc->sc_config1 = SEEQ_CFG1_PROMISCUOUS;
	else if ((ifp->if_flags & IFF_ALLMULTI) || sc->sc_variant == SEEQ_8004)
		sc->sc_config1 = SEEQ_CFG1_MULTICAST;
	else
		sc->sc_config1 = SEEQ_CFG1_BROADCAST;
	sc->sc_config1 |= SEEQ_CFG1_STATION_ADDR0;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG1, sc->sc_config1);

	/* Setup the Rx pointers */
	sc->sc_rx_ptr = sc->sc_tx_bufsize;

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_RX_PTR, sc->sc_rx_ptr);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_RX_END, sc->sc_rx_ptr >> 8);


	/* Place a NULL header at the beginning of the receive area */
	ea_writebuf(sc, NULL, sc->sc_rx_ptr, 0);

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, 0x0000);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, 0x0000);


	/* Configure TX. */
	DPRINTF(SEEQ_DEBUG_MISC, ("Configuring tx...\n"));

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_TX_PTR, 0x0000);

	sc->sc_config2 |= SEEQ_CFG2_OUTPUT;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG2, sc->sc_config2);

	/* Reset tx buffer pointers */
	sc->sc_tx_cur = 0;
	sc->sc_tx_used = 0;
	sc->sc_tx_next = 0;

	/* Place a NULL header at the beginning of the transmit area */
	ea_writebuf(sc, NULL, 0x0000, 0);

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, 0x0000);
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_BUFWIN, 0x0000);

	sc->sc_command |= SEEQ_CMD_TX_INTEN;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND, sc->sc_command);

	/* Turn on Rx */
	sc->sc_command |= SEEQ_CMD_RX_INTEN;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
			  sc->sc_command | SEEQ_CMD_RX_ON);

	/* TX_ON gets set by ea_txpacket when there's something to transmit. */


	/* Set flags appropriately. */
	ifp->if_flags |= IFF_RUNNING;
	ifp->if_flags &= ~IFF_OACTIVE;
	sc->sc_enabled = 1;

	/* And start output. */
	ea_start(ifp);

	splx(s);
	return 0;
}

/*
 * Start output on interface. Get datagrams from the queue and output them,
 * giving the receiver a chance between datagrams. Call only from splnet or
 * interrupt level!
 */

static void
ea_start(struct ifnet *ifp)
{
	struct seeq8005_softc *sc = ifp->if_softc;
	int s;

	s = splnet();
	DPRINTF(SEEQ_DEBUG_TX, ("ea_start()...\n"));

	/*
	 * Don't do anything if output is active.  seeq8005intr() will call
	 * us (actually ea_txpacket()) back when the card's ready for more
	 * frames.
	 */
	if (ifp->if_flags & IFF_OACTIVE) {
		splx(s);
		return;
	}

	/* Mark interface as output active */

	ifp->if_flags |= IFF_OACTIVE;

	/* tx packets */

	ea_txpacket(sc);
	splx(s);
}


/*
 * Transfer a packet to the interface buffer and start transmission
 *
 * Called at splnet()
 */

static void
ea_txpacket(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	struct mbuf *m0;
	struct ifnet *ifp;

	ifp = &sc->sc_ethercom.ec_if;

	/* Dequeue the next packet. */
	IFQ_DEQUEUE(&ifp->if_snd, m0);

	/* If there's nothing to send, return. */
	if (m0 == NULL) {
		ifp->if_flags &= ~IFF_OACTIVE;
		sc->sc_config2 |= SEEQ_CFG2_OUTPUT;
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG2, sc->sc_config2);
		DPRINTF(SEEQ_DEBUG_TX, ("tx finished\n"));
		return;
	}

	/* Give the packet to the bpf, if any. */
	bpf_mtap(ifp, m0, BPF_D_OUT);

	DPRINTF(SEEQ_DEBUG_TX, ("Tx new packet\n"));

	sc->sc_config2 &= ~SEEQ_CFG2_OUTPUT;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG2, sc->sc_config2);

	ea_writembuf(sc, m0, 0x0000);
	m_freem(m0);

	SEEQ_WRITE16(sc, iot, ioh, SEEQ_TX_PTR, 0x0000);

	/* Now transmit the datagram. */
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
			  sc->sc_command | SEEQ_CMD_TX_ON);

	/* Make sure we notice if the chip goes silent on us. */
	ifp->if_timer = 5;

	DPRINTF(SEEQ_DEBUG_TX,
	    ("st=%04x\n", SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS)));
	DPRINTF(SEEQ_DEBUG_TX, ("tx: queued\n"));
}

/*
 * Copy a packet from an mbuf to the transmit buffer on the card.
 *
 * Puts a valid Tx header at the start of the packet, and a null header at
 * the end.
 */
static int
ea_writembuf(struct seeq8005_softc *sc, struct mbuf *m0, int bufstart)
{
	struct mbuf *m;
	int len, nextpacket;
	uint8_t hdr[4];

	/*
	 * Copy the datagram to the packet buffer.
	 */
	len = 0;
	for (m = m0; m; m = m->m_next) {
		if (m->m_len == 0)
			continue;
		ea_writebuf(sc, mtod(m, u_char *), bufstart + 4 + len,
		    m->m_len);
		len += m->m_len;
	}

	if (len < ETHER_MIN_LEN) {
		ea_writebuf(sc, padbuf, bufstart + 4 + len,
		    ETHER_MIN_LEN - len);
		len = ETHER_MIN_LEN;
	}

	/* Follow it with a NULL packet header */
	memset(hdr, 0, 4);
	ea_writebuf(sc, hdr, bufstart + 4 + len, 4);

	/* Ok we now have a packet len bytes long in our packet buffer */
	DPRINTF(SEEQ_DEBUG_TX, ("ea_writembuf: length=%d\n", len));

	/* Write the packet header */
	nextpacket = bufstart + len + 4;
	hdr[0] = (nextpacket >> 8) & 0xff;
	hdr[1] = nextpacket & 0xff;
	hdr[2] = SEEQ_PKTCMD_TX | SEEQ_PKTCMD_DATA_FOLLOWS |
		SEEQ_TXCMD_XMIT_SUCCESS_INT | SEEQ_TXCMD_COLLISION_INT;
	hdr[3] = 0; /* Status byte -- will be updated by hardware. */
	ea_writebuf(sc, hdr, bufstart, 4);

	return len;
}

/*
 * Ethernet controller interrupt.
 */

int
seeq8005intr(void *arg)
{
	struct seeq8005_softc *sc = arg;
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	int status, handled;

	handled = 0;

	/* Get the controller status */
	status = SEEQ_READ16(sc, iot, ioh, SEEQ_STATUS);

	/* Tx interrupt ? */
	if (status & SEEQ_STATUS_TX_INT) {
		handled = 1;

		/* Acknowledge the interrupt */
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
				  sc->sc_command | SEEQ_CMD_TX_INTACK);

		ea_txint(sc);
	}


	/* Rx interrupt ? */
	if (status & SEEQ_STATUS_RX_INT) {
		handled = 1;

		/* Acknowledge the interrupt */
		SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
				  sc->sc_command | SEEQ_CMD_RX_INTACK);

		/* Processes the received packets */
		ea_rxint(sc);
	}

	if (handled)
		rnd_add_uint32(&sc->rnd_source, status);

	return handled;
}

static void
ea_txint(struct seeq8005_softc *sc)
{
	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	uint8_t txhdr[4];
	u_int txstatus;

	ea_readbuf(sc, txhdr, 0x0000, 4);

	DPRINTF(SEEQ_DEBUG_TX, ("txstatus=%02x %02x %02x %02x\n",
	    txhdr[0], txhdr[1], txhdr[2], txhdr[3]));
	txstatus = txhdr[3];

	/*
	 * If SEEQ_TXSTAT_COLLISION is set then we received at least
	 * one collision. On the 8004 we can find out exactly how many
	 * collisions occurred.
	 *
	 * The SEEQ_PKTSTAT_DONE will be set if the transmission has
	 * completed.
	 *
	 * If SEEQ_TXSTAT_COLLISION16 is set then 16 collisions
	 * occurred and the packet transmission was aborted.
	 * This situation is untested as present.
	 *
	 * The SEEQ_TXSTAT_BABBLE is untested as it should only be set
	 * when we deliberately transmit oversized packets (e.g. for
	 * 802.1Q).
	 */
	if (txstatus & SEEQ_TXSTAT_COLLISION) {
		switch (sc->sc_variant) {
		case SEEQ_8004: {
			int colls;

			/*
			 * The 8004 contains a 4 bit collision count
			 * in the status register.
			 */

			/* This appears to be broken on 80C04.AE */
/*			ifp->if_collisions +=
			    (txstatus >> SEEQ_TXSTAT_COLLISIONS_SHIFT)
			    & SEEQ_TXSTAT_COLLISION_MASK;*/

			/* Use the TX Collision register */
			ea_select_buffer(sc, SEEQ_BUFCODE_TX_COLLS);
			colls = bus_space_read_1(iot, ioh, SEEQ_BUFWIN);
			ifp->if_collisions += colls;
			break;
		}
		case SEEQ_8005:
			/* We known there was at least 1 collision */
			ifp->if_collisions++;
			break;
		}
	} else if (txstatus & SEEQ_TXSTAT_COLLISION16) {
		printf("seeq_intr: col16 %x\n", txstatus);
		ifp->if_collisions += 16;
		ifp->if_oerrors++;
	}

	/* Have we completed transmission on the packet ? */
	if (txstatus & SEEQ_PKTSTAT_DONE) {
		/* Clear watchdog timer. */
		ifp->if_timer = 0;
		ifp->if_flags &= ~IFF_OACTIVE;

		/* Update stats */
		ifp->if_opackets++;

		/* Tx next packet */

		ea_txpacket(sc);
	}
}

static void
ea_rxint(struct seeq8005_softc *sc)
{
	bus_space_tag_t iot = sc->sc_iot;
	bus_space_handle_t ioh = sc->sc_ioh;
	u_int addr;
	int len;
	int ctrl;
	int ptr;
	int status;
	uint8_t rxhdr[4];
	struct ifnet *ifp;

	ifp = &sc->sc_ethercom.ec_if;


	/* We start from the last rx pointer position */
	addr = sc->sc_rx_ptr;
	sc->sc_config2 &= ~SEEQ_CFG2_OUTPUT;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG2, sc->sc_config2);

	do {
		/* Read rx header */
		ea_readbuf(sc, rxhdr, addr, 4);

		/* Split the packet header */
		ptr = (rxhdr[0] << 8) | rxhdr[1];
		ctrl = rxhdr[2];
		status = rxhdr[3];

		DPRINTF(SEEQ_DEBUG_RX,
		    ("addr=%04x ptr=%04x ctrl=%02x status=%02x\n",
			addr, ptr, ctrl, status));

		/* Zero packet ptr ? then must be null header so exit */
		if (ptr == 0) break;

		/* Sanity-check the next-packet pointer and flags. */
		if (__predict_false(ptr < sc->sc_tx_bufsize ||
		    (ctrl & SEEQ_PKTCMD_TX))) {
			++ifp->if_ierrors;
			log(LOG_ERR,
			    "%s: Rx chain corrupt at %04x (ptr = %04x)\n",
			    device_xname(sc->sc_dev), addr, ptr);
			ea_init(ifp);
			return;
		}

		/* Get packet length */
		len = (ptr - addr) - 4;

		if (len < 0)
			len += sc->sc_rx_bufsize;
		DPRINTF(SEEQ_DEBUG_RX, ("len=%04x\n", len));

		/* Has the packet rx completed ? if not then exit */
		if ((status & SEEQ_PKTSTAT_DONE) == 0)
			break;

		/*
		 * Did we have any errors? then note error and go to
		 * next packet
		 */
		if (__predict_false(status &
			(SEEQ_RXSTAT_CRC_ERROR | SEEQ_RXSTAT_DRIBBLE_ERROR |
			 SEEQ_RXSTAT_SHORT_FRAME))) {
			++ifp->if_ierrors;
			log(LOG_WARNING,
			    "%s: rx packet error at %04x (err=%02x)\n",
			    device_xname(sc->sc_dev), addr, status & 0x0f);
			/* XXX shouldn't need to reset if it's genuine. */
			ea_init(ifp);
			return;
		}
		/*
		 * Is the packet too big?  We allow slightly oversize packets
		 * for vlan(4) and tcpdump purposes, but the rest of the world
		 * wants incoming packets in a single mbuf cluster.
		 */
		if (__predict_false(len > MCLBYTES)) {
			++ifp->if_ierrors;
			log(LOG_ERR,
			    "%s: rx packet size error at %04x (len=%d)\n",
			    device_xname(sc->sc_dev), addr, len);
			ea_init(ifp);
			return;
		}

		/* Pass data up to upper levels. */
		ea_read(sc, addr + 4, len);

		addr = ptr;
	} while (len != 0);

	sc->sc_config2 |= SEEQ_CFG2_OUTPUT;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_CONFIG2, sc->sc_config2);

	DPRINTF(SEEQ_DEBUG_RX, ("new rx ptr=%04x\n", addr));

	/* Store new rx pointer */
	sc->sc_rx_ptr = addr;
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_RX_END, sc->sc_rx_ptr >> 8);

	/* Make sure the receiver is on */
	SEEQ_WRITE16(sc, iot, ioh, SEEQ_COMMAND,
			  sc->sc_command | SEEQ_CMD_RX_ON);
}


/*
 * Pass a packet up to the higher levels.
 */

static void
ea_read(struct seeq8005_softc *sc, int addr, int len)
{
	struct mbuf *m;
	struct ifnet *ifp;

	ifp = &sc->sc_ethercom.ec_if;

	/* Pull packet off interface. */
	m = ea_get(sc, addr, len, ifp);
	if (m == NULL)
		return;

	if_percpuq_enqueue(ifp->if_percpuq, m);
}

/*
 * Pull read data off a interface.  Len is length of data, with local net
 * header stripped.  We copy the data into mbufs.  When full cluster sized
 * units are present we copy into clusters.
 */

struct mbuf *
ea_get(struct seeq8005_softc *sc, int addr, int totlen, struct ifnet *ifp)
{
	struct mbuf *top, **mp, *m;
	int len;
	u_int cp, epkt;

	cp = addr;
	epkt = cp + totlen;

	MGETHDR(m, M_DONTWAIT, MT_DATA);
	if (m == NULL)
		return NULL;
	m_set_rcvif(m, ifp);
	m->m_pkthdr.len = totlen;
	m->m_len = MHLEN;
	top = NULL;
	mp = &top;

	while (totlen > 0) {
		if (top) {
			MGET(m, M_DONTWAIT, MT_DATA);
			if (m == NULL) {
				m_freem(top);
				return NULL;
			}
			m->m_len = MLEN;
		}
		len = uimin(totlen, epkt - cp);
		if (len >= MINCLSIZE) {
			MCLGET(m, M_DONTWAIT);
			if (m->m_flags & M_EXT)
				m->m_len = len = uimin(len, MCLBYTES);
			else
				len = m->m_len;
		} else {
			/*
			 * Place initial small packet/header at end of mbuf.
			 */
			if (len < m->m_len) {
				if (top == NULL && len + max_linkhdr <= m->m_len)
					m->m_data += max_linkhdr;
				m->m_len = len;
			} else
				len = m->m_len;
		}
		if (top == NULL) {
			/* Make sure the payload is aligned */
			char *newdata = (char *)
			    ALIGN((char*)m->m_data +
				sizeof(struct ether_header)) -
			    sizeof(struct ether_header);
			len -= newdata - m->m_data;
			m->m_len = len;
			m->m_data = newdata;
		}
		ea_readbuf(sc, mtod(m, u_char *),
		    cp < SEEQ_MAX_BUFFER_SIZE ? cp : cp - sc->sc_rx_bufsize,
		    len);
		cp += len;
		*mp = m;
		mp = &m->m_next;
		totlen -= len;
		if (cp == epkt)
			cp = addr;
	}

	return top;
}

/*
 * Process an ioctl request.  Mostly boilerplate.
 */
static int
ea_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
	struct seeq8005_softc *sc = ifp->if_softc;
	int s, error = 0;

	s = splnet();
	switch (cmd) {

	default:
		error = ether_ioctl(ifp, cmd, data);
		if (error == ENETRESET) {
			/*
			 * Multicast list has changed; set the hardware filter
			 * accordingly.
			 */
			if (ifp->if_flags & IFF_RUNNING)
				ea_mc_reset(sc);
			error = 0;
		}
		break;
	}

	splx(s);
	return error;
}

/* Must be called at splnet() */

static void
ea_mc_reset(struct seeq8005_softc *sc)
{

	switch (sc->sc_variant) {
	case SEEQ_8004:
		ea_mc_reset_8004(sc);
		return;
	case SEEQ_8005:
		ea_mc_reset_8005(sc);
		return;
	}
}

static void
ea_mc_reset_8004(struct seeq8005_softc *sc)
{
	struct ethercom *ec = &sc->sc_ethercom;
	struct ifnet *ifp = &ec->ec_if;
	struct ether_multi *enm;
	uint32_t crc;
	int i;
	struct ether_multistep step;
	uint8_t af[8];

	/*
	 * Set up multicast address filter by passing all multicast addresses
	 * through a crc generator, and then using bits 2 - 7 as an index
	 * into the 64 bit logical address filter.  The high order bits
	 * selects the word, while the rest of the bits select the bit within
	 * the word.
	 */

	if (ifp->if_flags & IFF_PROMISC) {
		ifp->if_flags |= IFF_ALLMULTI;
		for (i = 0; i < 8; i++)
			af[i] = 0xff;
		return;
	}
	for (i = 0; i < 8; i++)
		af[i] = 0;
	ETHER_FIRST_MULTI(step, ec, enm);
	while (enm != NULL) {
		if (memcmp(enm->enm_addrlo, enm->enm_addrhi,
		    sizeof(enm->enm_addrlo)) != 0) {
			/*
			 * We must listen to a range of multicast addresses.
			 * For now, just accept all multicasts, rather than
			 * trying to set only those filter bits needed to match
			 * the range.  (At this time, the only use of address
			 * ranges is for IP multicast routing, for which the
			 * range is big enough to require all bits set.)
			 */
			ifp->if_flags |= IFF_ALLMULTI;
			for (i = 0; i < 8; i++)
				af[i] = 0xff;
			break;
		}

		crc = ether_crc32_be(enm->enm_addrlo, sizeof(enm->enm_addrlo));

		/* Just want the 6 most significant bits. */
		crc = (crc >> 2) & 0x3f;

		/* Turn on the corresponding bit in the filter. */
		af[crc >> 3] |= 1 << (crc & 0x7);

		ETHER_NEXT_MULTI(step, enm);
	}
	ifp->if_flags &= ~IFF_ALLMULTI;

	ea_select_buffer(sc, SEEQ_BUFCODE_MULTICAST);
		for (i = 0; i < 8; ++i)
			bus_space_write_1(sc->sc_iot, sc->sc_ioh,
			    SEEQ_BUFWIN, af[i]);
}

static void
ea_mc_reset_8005(struct seeq8005_softc *sc)
{
	struct ethercom *ec = &sc->sc_ethercom;
	struct ether_multi *enm;
	struct ether_multistep step;
	int naddr, maxaddrs;

	naddr = 0;
	maxaddrs = 5;
	ETHER_FIRST_MULTI(step, ec, enm);
	while (enm != NULL) {
		/* Have we got space? */
		if (naddr >= maxaddrs ||
		    memcmp(enm->enm_addrlo, enm->enm_addrhi, 6) != 0) {
			ec->ec_if.if_flags |= IFF_ALLMULTI;
			ea_ioctl(&ec->ec_if, SIOCSIFFLAGS, NULL);
			return;
		}
		ea_set_address(sc, 1 + naddr, enm->enm_addrlo);
		sc->sc_config1 |= SEEQ_CFG1_STATION_ADDR1 << naddr;
		naddr++;
		ETHER_NEXT_MULTI(step, enm);
	}
	for (; naddr < maxaddrs; naddr++)
		sc->sc_config1 &= ~(SEEQ_CFG1_STATION_ADDR1 << naddr);
	SEEQ_WRITE16(sc, sc->sc_iot, sc->sc_ioh, SEEQ_CONFIG1,
			  sc->sc_config1);
}

/*
 * Device timeout routine.
 */

static void
ea_watchdog(struct ifnet *ifp)
{
	struct seeq8005_softc *sc = ifp->if_softc;

	log(LOG_ERR, "%s: lost Tx interrupt (status = 0x%04x)\n",
	    device_xname(sc->sc_dev),
	    SEEQ_READ16(sc, sc->sc_iot, sc->sc_ioh, SEEQ_STATUS));
	ifp->if_oerrors++;

	/* Kick the interface */

	ea_init(ifp);

	ifp->if_timer = 0;
}

/* End of seeq8005.c */