freebsd-nq/sys/dev/ep/if_ep.c

/*
 * Copyright (c) 1994 Herb Peyerl <hpeyerl@novatel.ca>
 * 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 Herb Peyerl.
 * 4. The name of Herb Peyerl may not 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 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.
 *
 *	if_ep.c,v 1.19 1995/01/24 20:53:45 davidg Exp
 */

/*
 *	Modified from the FreeBSD 1.1.5.1 version by:
 *		 	Andres Vega Garcia
 *			INRIA - Sophia Antipolis, France
 *			avega@sophia.inria.fr
 */

/*
 * $FreeBSD$
 *
 *  Promiscuous mode added and interrupt logic slightly changed
 *  to reduce the number of adapter failures. Transceiver select
 *  logic changed to use value from EEPROM. Autoconfiguration
 *  features added.
 *  Done by:
 *          Serge Babkin
 *          Chelindbank (Chelyabinsk, Russia)
 *          babkin@hq.icb.chel.su
 */

/*
 * Pccard support for 3C589 by:
 *		HAMADA Naoki
 *		nao@tom-yam.or.jp
 */

#include "ep.h"
#if NEP > 0

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

#include <net/ethernet.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <net/bpf.h>

#include <machine/clock.h>

#include <i386/isa/elink.h>
#include <dev/ep/if_epreg.h>
#include <dev/ep/if_epvar.h>

/* Exported variables */
struct	ep_softc *	ep_softc[NEP];
struct	ep_board	ep_board[EP_MAX_BOARDS + 1];
int	ep_boards;
u_long	ep_unit;

static	char *		ep_conn_type[] = {"UTP", "AUI", "???", "BNC"};

static	int		eeprom_rdy	__P((struct ep_softc *sc));
static	int		epioctl		__P((struct ifnet * ifp, u_long, caddr_t));
static	void		epinit		__P((void *));
static	void		epread		__P((struct ep_softc *));
static	void		epstart		__P((struct ifnet *));
static	void		epstop		__P((struct ep_softc *));
static	void		epwatchdog	__P((struct ifnet *));

#define EP_FTST(sc, f)	(sc->stat&(f))
#define EP_FSET(sc, f)	(sc->stat|=(f))
#define EP_FRST(sc, f)	(sc->stat&=~(f))

static int
eeprom_rdy(sc)
    struct ep_softc *sc;
{
    int i;

    for (i = 0; is_eeprom_busy(BASE) && i < MAX_EEPROMBUSY; i++)
	continue;
    if (i >= MAX_EEPROMBUSY) {
	printf("ep%d: eeprom failed to come ready.\n", sc->unit);
	return (0);
    }
    return (1);
}

/*
 * get_e: gets a 16 bits word from the EEPROM. we must have set the window
 * before
 */
u_int16_t
get_e(sc, offset)
    struct ep_softc *sc;
    int offset;
{
    if (!eeprom_rdy(sc))
	return (0xffff);
    outw(BASE + EP_W0_EEPROM_COMMAND, (EEPROM_CMD_RD << sc->epb->cmd_off) | offset);
    if (!eeprom_rdy(sc))
	return (0xffff);
    return (inw(BASE + EP_W0_EEPROM_DATA));
}

struct ep_softc *
ep_alloc(unit, epb)
    int unit;
    struct ep_board *epb;
{
    struct	ep_softc *sc;

    if (unit >= NEP) {
	printf("ep: unit number (%d) too high\n", unit);
	return NULL;
    }
 
    /*
     * Allocate a storage area for us
     */
    if (ep_softc[unit]) {
	printf("ep%d: unit number already allocated to another "
	       "adaptor\n", unit);
	return NULL;
    }

    sc = malloc(sizeof(struct ep_softc), M_DEVBUF, M_NOWAIT);
    if (!sc) {
	printf("ep%d: cannot malloc!\n", unit);
	return NULL;
    }
    bzero(sc, sizeof(struct ep_softc));
    ep_softc[unit] = sc;
    sc->unit = unit;
    sc->ep_io_addr = epb->epb_addr;
    sc->epb = epb;

    return(sc);
}

void
ep_free(sc)
    struct ep_softc *sc;
{
    ep_softc[sc->unit] = NULL;
    free(sc, M_DEVBUF);
    return;
}

int
ep_attach(sc)
    struct ep_softc *sc;
{
    struct ifnet *ifp = &sc->arpcom.ac_if;
    u_short *p;
    int i;
    int attached;

    sc->gone = 0;
    attached = (ifp->if_softc != 0);

    printf("ep%d: ", sc->unit);
    /*
     * Current media type
     */
    if (sc->ep_connectors & AUI) {
	printf("aui");
	if (sc->ep_connectors & ~AUI)
		printf("/");
    }
    if (sc->ep_connectors & UTP) {
	printf("utp");
	if (sc->ep_connectors & BNC)
		printf("/");
    }
    if (sc->ep_connectors & BNC) {
	printf("bnc");
    }

    printf("[*%s*]", ep_conn_type[sc->ep_connector]);

    /*
     * Setup the station address
     */
    p = (u_short *) & sc->arpcom.ac_enaddr;
    GO_WINDOW(2);
    for (i = 0; i < 3; i++) {
	p[i] = htons(sc->epb->eth_addr[i]);
	outw(BASE + EP_W2_ADDR_0 + (i * 2), ntohs(p[i]));
    }
    printf(" address %6D\n", sc->arpcom.ac_enaddr, ":");

    ifp->if_softc = sc;
    ifp->if_unit = sc->unit;
    ifp->if_name = "ep";
    ifp->if_mtu = ETHERMTU;
    ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
    ifp->if_output = ether_output;
    ifp->if_start = epstart;
    ifp->if_ioctl = epioctl;
    ifp->if_watchdog = epwatchdog;
    ifp->if_init = epinit;

    if (!attached) {
	if_attach(ifp);
	ether_ifattach(ifp);
    }

#ifdef EP_LOCAL_STATS
    sc->rx_no_first = sc->rx_no_mbuf =
	sc->rx_bpf_disc = sc->rx_overrunf = sc->rx_overrunl =
	sc->tx_underrun = 0;
#endif
    EP_FSET(sc, F_RX_FIRST);
    sc->top = sc->mcur = 0;

    if (!attached) {
	bpfattach(ifp, DLT_EN10MB, sizeof(struct ether_header));
    }
    return 0;
}


/*
 * The order in here seems important. Otherwise we may not receive
 * interrupts. ?!
 */
static void
epinit(xsc)
    void *xsc;
{
    struct ep_softc *sc = xsc;
    register struct ifnet *ifp = &sc->arpcom.ac_if;
    int s, i, j;

    if (sc->gone)
	return;

	/*
    if (ifp->if_addrlist == (struct ifaddr *) 0)
	return;
	*/

    s = splimp();
    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);

    GO_WINDOW(0);
    outw(BASE + EP_COMMAND, STOP_TRANSCEIVER);
    GO_WINDOW(4);
    outw(BASE + EP_W4_MEDIA_TYPE, DISABLE_UTP);
    GO_WINDOW(0);

    /* Disable the card */
    outw(BASE + EP_W0_CONFIG_CTRL, 0);

    /* Enable the card */
    outw(BASE + EP_W0_CONFIG_CTRL, ENABLE_DRQ_IRQ);

    GO_WINDOW(2);

    /* Reload the ether_addr. */
    for (i = 0; i < 6; i++)
	outb(BASE + EP_W2_ADDR_0 + i, sc->arpcom.ac_enaddr[i]);

    outw(BASE + EP_COMMAND, RX_RESET);
    outw(BASE + EP_COMMAND, TX_RESET);
    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);

    /* Window 1 is operating window */
    GO_WINDOW(1);
    for (i = 0; i < 31; i++)
	inb(BASE + EP_W1_TX_STATUS);

    /* get rid of stray intr's */
    outw(BASE + EP_COMMAND, ACK_INTR | 0xff);

    outw(BASE + EP_COMMAND, SET_RD_0_MASK | S_5_INTS);

    outw(BASE + EP_COMMAND, SET_INTR_MASK | S_5_INTS);

    if (ifp->if_flags & IFF_PROMISC)
	outw(BASE + EP_COMMAND, SET_RX_FILTER | FIL_INDIVIDUAL |
	 FIL_GROUP | FIL_BRDCST | FIL_ALL);
    else
	outw(BASE + EP_COMMAND, SET_RX_FILTER | FIL_INDIVIDUAL |
	 FIL_GROUP | FIL_BRDCST);

     /*
      * S.B.
      *
      * Now behavior was slightly changed:
      *
      * if any of flags link[0-2] is used and its connector is
      * physically present the following connectors are used:
      *
      *   link0 - AUI * highest precedence
      *   link1 - BNC
      *   link2 - UTP * lowest precedence
      *
      * If none of them is specified then
      * connector specified in the EEPROM is used
      * (if present on card or AUI if not).
      *
      */

    /* Set the xcvr. */
    if (ifp->if_flags & IFF_LINK0 && sc->ep_connectors & AUI) {
	i = ACF_CONNECTOR_AUI;
    } else if (ifp->if_flags & IFF_LINK1 && sc->ep_connectors & BNC) {
	i = ACF_CONNECTOR_BNC;
    } else if (ifp->if_flags & IFF_LINK2 && sc->ep_connectors & UTP) {
	i = ACF_CONNECTOR_UTP;
    } else {
	i = sc->ep_connector;
    }
    GO_WINDOW(0);
    j = inw(BASE + EP_W0_ADDRESS_CFG) & 0x3fff;
    outw(BASE + EP_W0_ADDRESS_CFG, j | (i << ACF_CONNECTOR_BITS));

    switch(i) {
      case ACF_CONNECTOR_UTP:
	if (sc->ep_connectors & UTP) {
	    GO_WINDOW(4);
	    outw(BASE + EP_W4_MEDIA_TYPE, ENABLE_UTP);
	}
	break;
      case ACF_CONNECTOR_BNC:
	if (sc->ep_connectors & BNC) {
	    outw(BASE + EP_COMMAND, START_TRANSCEIVER);
	    DELAY(DELAY_MULTIPLE * 1000);
	}
	break;
      case ACF_CONNECTOR_AUI:
	/* nothing to do */
	break;
      default:
	printf("ep%d: strange connector type in EEPROM: assuming AUI\n",
	       sc->unit);
	break;
    }

    outw(BASE + EP_COMMAND, RX_ENABLE);
    outw(BASE + EP_COMMAND, TX_ENABLE);

    ifp->if_flags |= IFF_RUNNING;
    ifp->if_flags &= ~IFF_OACTIVE;	/* just in case */

#ifdef EP_LOCAL_STATS
    sc->rx_no_first = sc->rx_no_mbuf =
	sc->rx_bpf_disc = sc->rx_overrunf = sc->rx_overrunl =
	sc->tx_underrun = 0;
#endif
    EP_FSET(sc, F_RX_FIRST);
    if (sc->top) {
	m_freem(sc->top);
	sc->top = sc->mcur = 0;
    }
    outw(BASE + EP_COMMAND, SET_RX_EARLY_THRESH | RX_INIT_EARLY_THRESH);
    outw(BASE + EP_COMMAND, SET_TX_START_THRESH | 16);

    /*
     * Store up a bunch of mbuf's for use later. (MAX_MBS). First we free up
     * any that we had in case we're being called from intr or somewhere
     * else.
     */

    GO_WINDOW(1);
    epstart(ifp);

    splx(s);
}

static const char padmap[] = {0, 3, 2, 1};

static void
epstart(ifp)
    struct ifnet *ifp;
{
    register struct ep_softc *sc = ifp->if_softc;
    register u_int len;
    register struct mbuf *m;
    struct mbuf *top;
    int s, pad;

    if (sc->gone) {
	return;
    }

    s = splimp();
    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);
    if (ifp->if_flags & IFF_OACTIVE) {
	splx(s);
	return;
    }
startagain:
    /* Sneak a peek at the next packet */
    m = ifp->if_snd.ifq_head;
    if (m == 0) {
	splx(s);
	return;
    }
    for (len = 0, top = m; m; m = m->m_next)
	len += m->m_len;

    pad = padmap[len & 3];

    /*
     * The 3c509 automatically pads short packets to minimum ethernet length,
     * but we drop packets that are too large. Perhaps we should truncate
     * them instead?
     */
    if (len + pad > ETHER_MAX_LEN) {
	/* packet is obviously too large: toss it */
	++ifp->if_oerrors;
	IF_DEQUEUE(&ifp->if_snd, m);
	m_freem(m);
	goto readcheck;
    }
    if (inw(BASE + EP_W1_FREE_TX) < len + pad + 4) {
	/* no room in FIFO */
	outw(BASE + EP_COMMAND, SET_TX_AVAIL_THRESH | (len + pad + 4));
	/* make sure */
	if (inw(BASE + EP_W1_FREE_TX) < len + pad + 4) {
	    ifp->if_flags |= IFF_OACTIVE;
	    splx(s);
	    return;
	}
    }
    IF_DEQUEUE(&ifp->if_snd, m);

    outw(BASE + EP_W1_TX_PIO_WR_1, len); 
    outw(BASE + EP_W1_TX_PIO_WR_1, 0x0);	/* Second dword meaningless */

    for (top = m; m != 0; m = m->m_next)
	if (EP_FTST(sc, F_ACCESS_32_BITS)) {
	    outsl(BASE + EP_W1_TX_PIO_WR_1, mtod(m, caddr_t),
		  m->m_len / 4);
	    if (m->m_len & 3)
		outsb(BASE + EP_W1_TX_PIO_WR_1,
		      mtod(m, caddr_t) + (m->m_len & (~3)),
		      m->m_len & 3);
	} else {
	    outsw(BASE + EP_W1_TX_PIO_WR_1, mtod(m, caddr_t), m->m_len / 2);
	    if (m->m_len & 1)
		outb(BASE + EP_W1_TX_PIO_WR_1,
		     *(mtod(m, caddr_t) + m->m_len - 1));
	}

    while (pad--)
	outb(BASE + EP_W1_TX_PIO_WR_1, 0);	/* Padding */

    if (ifp->if_bpf) {
	bpf_mtap(ifp, top);
    }

    ifp->if_timer = 2;
    ifp->if_opackets++;
    m_freem(top);

    /*
     * Is another packet coming in? We don't want to overflow the tiny RX
     * fifo.
     */
readcheck:
    if (inw(BASE + EP_W1_RX_STATUS) & RX_BYTES_MASK) {
	/*
	 * we check if we have packets left, in that case we prepare to come
	 * back later
	 */
	if (ifp->if_snd.ifq_head) {
	    outw(BASE + EP_COMMAND, SET_TX_AVAIL_THRESH | 8);
	}
	splx(s);
	return;
    }
    goto startagain;
}

void
ep_intr(arg)
    void *arg;
{
    struct ep_softc *sc;
    register int status;
    struct ifnet *ifp;
    int x;

    x = splbio();

    sc = (struct ep_softc *)arg;

    ifp = &sc->arpcom.ac_if;

    outw(BASE + EP_COMMAND, SET_INTR_MASK); /* disable all Ints */

rescan:

    while ((status = inw(BASE + EP_STATUS)) & S_5_INTS) {

	/* first acknowledge all interrupt sources */
	outw(BASE + EP_COMMAND, ACK_INTR | (status & S_MASK));

	if (status & (S_RX_COMPLETE | S_RX_EARLY)) {
	    epread(sc);
	    continue;
	}
	if (status & S_TX_AVAIL) {
	    /* we need ACK */
	    ifp->if_timer = 0;
	    ifp->if_flags &= ~IFF_OACTIVE;
	    GO_WINDOW(1);
	    inw(BASE + EP_W1_FREE_TX);
	    epstart(ifp);
	}
	if (status & S_CARD_FAILURE) {
	    ifp->if_timer = 0;
#ifdef EP_LOCAL_STATS
	    printf("\nep%d:\n\tStatus: %x\n", sc->unit, status);
	    GO_WINDOW(4);
	    printf("\tFIFO Diagnostic: %x\n", inw(BASE + EP_W4_FIFO_DIAG));
	    printf("\tStat: %x\n", sc->stat);
	    printf("\tIpackets=%d, Opackets=%d\n",
		ifp->if_ipackets, ifp->if_opackets);
	    printf("\tNOF=%d, NOMB=%d, BPFD=%d, RXOF=%d, RXOL=%d, TXU=%d\n",
		   sc->rx_no_first, sc->rx_no_mbuf, sc->rx_bpf_disc, sc->rx_overrunf,
		   sc->rx_overrunl, sc->tx_underrun);
#else

#ifdef DIAGNOSTIC
	    printf("ep%d: Status: %x (input buffer overflow)\n", sc->unit, status);
#else
	    ++ifp->if_ierrors;
#endif

#endif
	    epinit(sc);
	    splx(x);
	    return;
	}
	if (status & S_TX_COMPLETE) {
	    ifp->if_timer = 0;
	    /* we  need ACK. we do it at the end */
	    /*
	     * We need to read TX_STATUS until we get a 0 status in order to
	     * turn off the interrupt flag.
	     */
	    while ((status = inb(BASE + EP_W1_TX_STATUS)) & TXS_COMPLETE) {
		if (status & TXS_SUCCES_INTR_REQ);
		else if (status & (TXS_UNDERRUN | TXS_JABBER | TXS_MAX_COLLISION)) {
		    outw(BASE + EP_COMMAND, TX_RESET);
		    if (status & TXS_UNDERRUN) {
#ifdef EP_LOCAL_STATS
			sc->tx_underrun++;
#endif
		    } else {
			if (status & TXS_JABBER);
			else	/* TXS_MAX_COLLISION - we shouldn't get here */
			    ++ifp->if_collisions;
		    }
		    ++ifp->if_oerrors;
		    outw(BASE + EP_COMMAND, TX_ENABLE);
		    /*
		     * To have a tx_avail_int but giving the chance to the
		     * Reception
		     */
		    if (ifp->if_snd.ifq_head) {
			outw(BASE + EP_COMMAND, SET_TX_AVAIL_THRESH | 8);
		    }
		}
		outb(BASE + EP_W1_TX_STATUS, 0x0);	/* pops up the next
							 * status */
	    }			/* while */
	    ifp->if_flags &= ~IFF_OACTIVE;
	    GO_WINDOW(1);
	    inw(BASE + EP_W1_FREE_TX);
	    epstart(ifp);
	}			/* end TX_COMPLETE */
    }

    outw(BASE + EP_COMMAND, C_INTR_LATCH);	/* ACK int Latch */

    if ((status = inw(BASE + EP_STATUS)) & S_5_INTS)
	goto rescan;

    /* re-enable Ints */
    outw(BASE + EP_COMMAND, SET_INTR_MASK | S_5_INTS);

    splx(x);
}

static void
epread(sc)
    register struct ep_softc *sc;
{
    struct ether_header *eh;
    struct mbuf *top, *mcur, *m;
    struct ifnet *ifp;
    int lenthisone;

    short rx_fifo2, status;
    register short rx_fifo;

    ifp = &sc->arpcom.ac_if;
    status = inw(BASE + EP_W1_RX_STATUS);

read_again:

    if (status & ERR_RX) {
	++ifp->if_ierrors;
	if (status & ERR_RX_OVERRUN) {
	    /*
	     * we can think the rx latency is actually greather than we
	     * expect
	     */
#ifdef EP_LOCAL_STATS
	    if (EP_FTST(sc, F_RX_FIRST))
		sc->rx_overrunf++;
	    else
		sc->rx_overrunl++;
#endif
	}
	goto out;
    }
    rx_fifo = rx_fifo2 = status & RX_BYTES_MASK;

    if (EP_FTST(sc, F_RX_FIRST)) {
	MGETHDR(m, M_DONTWAIT, MT_DATA);
	if (!m)
	    goto out;
	if (rx_fifo >= MINCLSIZE)
	    MCLGET(m, M_DONTWAIT);
	sc->top = sc->mcur = top = m;
#define EROUND  ((sizeof(struct ether_header) + 3) & ~3)
#define EOFF    (EROUND - sizeof(struct ether_header))
	top->m_data += EOFF;

	/* Read what should be the header. */
	insw(BASE + EP_W1_RX_PIO_RD_1,
	     mtod(top, caddr_t), sizeof(struct ether_header) / 2);
	top->m_len = sizeof(struct ether_header);
	rx_fifo -= sizeof(struct ether_header);
	sc->cur_len = rx_fifo2;
    } else {
	/* come here if we didn't have a complete packet last time */
	top = sc->top;
	m = sc->mcur;
	sc->cur_len += rx_fifo2;
    }

    /* Reads what is left in the RX FIFO */
    while (rx_fifo > 0) {
	lenthisone = min(rx_fifo, M_TRAILINGSPACE(m));
	if (lenthisone == 0) {	/* no room in this one */
	    mcur = m;
	    MGET(m, M_DONTWAIT, MT_DATA);
	    if (!m)
		goto out;
	    if (rx_fifo >= MINCLSIZE)
		MCLGET(m, M_DONTWAIT);
	    m->m_len = 0;
	    mcur->m_next = m;
	    lenthisone = min(rx_fifo, M_TRAILINGSPACE(m));
	}
	if (EP_FTST(sc, F_ACCESS_32_BITS)) { /* default for EISA configured cards*/
	    insl(BASE + EP_W1_RX_PIO_RD_1, mtod(m, caddr_t) + m->m_len,
		 lenthisone / 4);
	    m->m_len += (lenthisone & ~3);
	    if (lenthisone & 3)
		insb(BASE + EP_W1_RX_PIO_RD_1,
		     mtod(m, caddr_t) + m->m_len,
		     lenthisone & 3);
	    m->m_len += (lenthisone & 3);
	} else {
	    insw(BASE + EP_W1_RX_PIO_RD_1, mtod(m, caddr_t) + m->m_len,
		 lenthisone / 2);
	    m->m_len += lenthisone;
	    if (lenthisone & 1)
		*(mtod(m, caddr_t) + m->m_len - 1) = inb(BASE + EP_W1_RX_PIO_RD_1);
	}
	rx_fifo -= lenthisone;
    }

    if (status & ERR_RX_INCOMPLETE) {	/* we haven't received the complete
					 * packet */
	sc->mcur = m;
#ifdef EP_LOCAL_STATS
	sc->rx_no_first++;	/* to know how often we come here */
#endif
	EP_FRST(sc, F_RX_FIRST);
	if (!((status = inw(BASE + EP_W1_RX_STATUS)) & ERR_RX_INCOMPLETE)) {
	    /* we see if by now, the packet has completly arrived */
	    goto read_again;
	}
	outw(BASE + EP_COMMAND, SET_RX_EARLY_THRESH | RX_NEXT_EARLY_THRESH);
	return;
    }
    outw(BASE + EP_COMMAND, RX_DISCARD_TOP_PACK);
    ++ifp->if_ipackets;
    EP_FSET(sc, F_RX_FIRST);
    top->m_pkthdr.rcvif = &sc->arpcom.ac_if;
    top->m_pkthdr.len = sc->cur_len;

    if (ifp->if_bpf) {
	bpf_mtap(ifp, top);

	/*
	 * Note that the interface cannot be in promiscuous mode if there are
	 * no BPF listeners.  And if we are in promiscuous mode, we have to
	 * check if this packet is really ours.
	 */
	eh = mtod(top, struct ether_header *);
	if ((ifp->if_flags & IFF_PROMISC) &&
	    (eh->ether_dhost[0] & 1) == 0 &&
	    bcmp(eh->ether_dhost, sc->arpcom.ac_enaddr,
		 sizeof(eh->ether_dhost)) != 0 &&
	    bcmp(eh->ether_dhost, etherbroadcastaddr,
		 sizeof(eh->ether_dhost)) != 0) {
	    if (sc->top) {
		m_freem(sc->top);
		sc->top = 0;
	    }
	    EP_FSET(sc, F_RX_FIRST);
#ifdef EP_LOCAL_STATS
	    sc->rx_bpf_disc++;
#endif
	    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);
	    outw(BASE + EP_COMMAND, SET_RX_EARLY_THRESH | RX_INIT_EARLY_THRESH);
	    return;
	}
    }

    eh = mtod(top, struct ether_header *);
    m_adj(top, sizeof(struct ether_header));
    ether_input(ifp, eh, top);
    sc->top = 0;
    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);
    outw(BASE + EP_COMMAND, SET_RX_EARLY_THRESH | RX_INIT_EARLY_THRESH);
    return;

out:
    outw(BASE + EP_COMMAND, RX_DISCARD_TOP_PACK);
    if (sc->top) {
	m_freem(sc->top);
	sc->top = 0;
#ifdef EP_LOCAL_STATS
	sc->rx_no_mbuf++;
#endif
    }
    EP_FSET(sc, F_RX_FIRST);
    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);
    outw(BASE + EP_COMMAND, SET_RX_EARLY_THRESH | RX_INIT_EARLY_THRESH);
}

/*
 * Look familiar?
 */
static int
epioctl(ifp, cmd, data)
    register struct ifnet *ifp;
    u_long cmd;
    caddr_t data;
{
    struct ep_softc *sc = ifp->if_softc;
    int s, error = 0;

    s = splimp();

    switch (cmd) {
      case SIOCSIFADDR:
      case SIOCGIFADDR:
      case SIOCSIFMTU:
        error = ether_ioctl(ifp, cmd, data);
        break;

      case SIOCSIFFLAGS:

	if ((ifp->if_flags & IFF_UP) == 0 && ifp->if_flags & IFF_RUNNING) {
	    ifp->if_flags &= ~IFF_RUNNING;
	    epstop(sc);
	    break;
	} else {
	    /* reinitialize card on any parameter change */
	    epinit(sc);
	    break;
	}

	/* NOTREACHED */
	break;
#ifdef notdef
      case SIOCGHWADDR:
	bcopy((caddr_t) sc->sc_addr, (caddr_t) & ifr->ifr_data,
	      sizeof(sc->sc_addr));
	break;
#endif
	case SIOCADDMULTI:
	case SIOCDELMULTI:
	    /*
	     * The Etherlink III has no programmable multicast
	     * filter.  We always initialize the card to be
	     * promiscuous to multicast, since we're always a
	     * member of the ALL-SYSTEMS group, so there's no
	     * need to process SIOC*MULTI requests.
	     */
	    error = 0;
	    break;
      default:
		error = EINVAL;
    }

    splx(s);

    return (error);
}

static void
epwatchdog(ifp)
    struct ifnet *ifp;
{
    struct ep_softc *sc = ifp->if_softc;

    /*
    printf("ep: watchdog\n");

    log(LOG_ERR, "ep%d: watchdog\n", ifp->if_unit);
    ifp->if_oerrors++;
    */

    if (sc->gone) {
	return;
    }

    ifp->if_flags &= ~IFF_OACTIVE;
    epstart(ifp);
    ep_intr(ifp->if_softc);
}

static void
epstop(sc)
    struct ep_softc *sc;
{
    if (sc->gone) {
	return;
    }

    outw(BASE + EP_COMMAND, RX_DISABLE);
    outw(BASE + EP_COMMAND, RX_DISCARD_TOP_PACK);
    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);
    outw(BASE + EP_COMMAND, TX_DISABLE);
    outw(BASE + EP_COMMAND, STOP_TRANSCEIVER);
    outw(BASE + EP_COMMAND, RX_RESET);
    outw(BASE + EP_COMMAND, TX_RESET);
    while (inw(BASE + EP_STATUS) & S_COMMAND_IN_PROGRESS);
    outw(BASE + EP_COMMAND, C_INTR_LATCH);
    outw(BASE + EP_COMMAND, SET_RD_0_MASK);
    outw(BASE + EP_COMMAND, SET_INTR_MASK);
    outw(BASE + EP_COMMAND, SET_RX_FILTER);
}

#endif				/* NEP > 0 */