/*
 * Copyright (c) 2002 Myson Technology Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification, immediately at the beginning of the file.
 * 2. The name of the author 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 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.
 *
 * Written by: yen_cw@myson.com.tw  available at: http://www.myson.com.tw/
 *
 * $FreeBSD: src/sys/dev/my/if_my.c,v 1.2.2.4 2002/04/17 02:05:27 julian Exp $
 *
 * Myson fast ethernet PCI NIC driver
 *
 * $Id: if_my.c,v 1.40 2001/11/30 03:55:00 <yen_cw@myson.com.tw> wpaul Exp $
 */
#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/interrupt.h>
#include <sys/socket.h>
#include <sys/queue.h>
#include <sys/bus.h>
#include <sys/module.h>
#include <sys/serialize.h>
#include <sys/rman.h>

#include <sys/thread2.h>

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

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

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

/*
 * #define MY_USEIOSPACE
 */

static int      MY_USEIOSPACE = 1;

#ifdef MY_USEIOSPACE
#define MY_RES                  SYS_RES_IOPORT
#define MY_RID                  MY_PCI_LOIO
#else
#define MY_RES                  SYS_RES_MEMORY
#define MY_RID                  MY_PCI_LOMEM
#endif


#include "if_myreg.h"

/*
 * Various supported device vendors/types and their names.
 */
static struct my_type my_devs[] = {
        {MYSONVENDORID, MTD800ID, "Myson MTD80X Based Fast Ethernet Card"},
        {MYSONVENDORID, MTD803ID, "Myson MTD80X Based Fast Ethernet Card"},
        {MYSONVENDORID, MTD891ID, "Myson MTD89X Based Giga Ethernet Card"},
        {0, 0, NULL}
};

/*
 * Various supported PHY vendors/types and their names. Note that this driver
 * will work with pretty much any MII-compliant PHY, so failure to positively
 * identify the chip is not a fatal error.
 */
static struct my_type my_phys[] = {
        {MysonPHYID0, MysonPHYID0, "<MYSON MTD981>"},
        {SeeqPHYID0, SeeqPHYID0, "<SEEQ 80225>"},
        {AhdocPHYID0, AhdocPHYID0, "<AHDOC 101>"},
        {MarvellPHYID0, MarvellPHYID0, "<MARVELL 88E1000>"},
        {LevelOnePHYID0, LevelOnePHYID0, "<LevelOne LXT1000>"},
        {0, 0, "<MII-compliant physical interface>"}
};

static int      my_probe(device_t);
static int      my_attach(device_t);
static int      my_detach(device_t);
static int      my_newbuf(struct my_softc *, struct my_chain_onefrag *);
static int      my_encap(struct my_softc *, struct my_chain *, struct mbuf *);
static void     my_rxeof(struct my_softc *);
static void     my_txeof(struct my_softc *);
static void     my_txeoc(struct my_softc *);
static void     my_intr(void *);
static void     my_start(struct ifnet *, struct ifaltq_subque *);
static int      my_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
static void     my_init(void *);
static void     my_stop(struct my_softc *);
static void     my_watchdog(struct ifnet *);
static void     my_shutdown(device_t);
static int      my_ifmedia_upd(struct ifnet *);
static void     my_ifmedia_sts(struct ifnet *, struct ifmediareq *);
static u_int16_t my_phy_readreg(struct my_softc *, int);
static void     my_phy_writereg(struct my_softc *, int, int);
static void     my_autoneg_xmit(struct my_softc *);
static void     my_autoneg_mii(struct my_softc *, int, int);
static void     my_setmode_mii(struct my_softc *, int);
static void     my_getmode_mii(struct my_softc *);
static void     my_setcfg(struct my_softc *, int);
static u_int8_t my_calchash(caddr_t);
static void     my_setmulti(struct my_softc *);
static void     my_reset(struct my_softc *);
static int      my_list_rx_init(struct my_softc *);
static int      my_list_tx_init(struct my_softc *);
static long     my_send_cmd_to_phy(struct my_softc *, int, int);

#define MY_SETBIT(sc, reg, x) CSR_WRITE_4(sc, reg, CSR_READ_4(sc, reg) | x)
#define MY_CLRBIT(sc, reg, x) CSR_WRITE_4(sc, reg, CSR_READ_4(sc, reg) & ~x)

static device_method_t my_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe, my_probe),
        DEVMETHOD(device_attach, my_attach),
        DEVMETHOD(device_detach, my_detach),
        DEVMETHOD(device_shutdown, my_shutdown),

        DEVMETHOD_END
};

static driver_t my_driver = {
        "my",
        my_methods,
        sizeof(struct my_softc)
};

static devclass_t my_devclass;

DECLARE_DUMMY_MODULE(if_my);
DRIVER_MODULE(if_my, pci, my_driver, my_devclass, NULL, NULL);

static long
my_send_cmd_to_phy(struct my_softc * sc, int opcode, int regad)
{
        long            miir;
        int             i;
        int             mask, data;

        /* enable MII output */
        miir = CSR_READ_4(sc, MY_MANAGEMENT);
        miir &= 0xfffffff0;

        miir |= MY_MASK_MIIR_MII_WRITE + MY_MASK_MIIR_MII_MDO;

        /* send 32 1's preamble */
        for (i = 0; i < 32; i++) {
                /* low MDC; MDO is already high (miir) */
                miir &= ~MY_MASK_MIIR_MII_MDC;
                CSR_WRITE_4(sc, MY_MANAGEMENT, miir);

                /* high MDC */
                miir |= MY_MASK_MIIR_MII_MDC;
                CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
        }

        /* calculate ST+OP+PHYAD+REGAD+TA */
        data = opcode | (sc->my_phy_addr << 7) | (regad << 2);

        /* sent out */
        mask = 0x8000;
        while (mask) {
                /* low MDC, prepare MDO */
                miir &= ~(MY_MASK_MIIR_MII_MDC + MY_MASK_MIIR_MII_MDO);
                if (mask & data)
                        miir |= MY_MASK_MIIR_MII_MDO;

                CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
                /* high MDC */
                miir |= MY_MASK_MIIR_MII_MDC;
                CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
                DELAY(30);

                /* next */
                mask >>= 1;
                if (mask == 0x2 && opcode == MY_OP_READ)
                        miir &= ~MY_MASK_MIIR_MII_WRITE;
        }

        return miir;
}


static          u_int16_t
my_phy_readreg(struct my_softc * sc, int reg)
{
        long            miir;
        int             mask, data;

        if (sc->my_info->my_did == MTD803ID)
                data = CSR_READ_2(sc, MY_PHYBASE + reg * 2);
        else {
                miir = my_send_cmd_to_phy(sc, MY_OP_READ, reg);

                /* read data */
                mask = 0x8000;
                data = 0;
                while (mask) {
                        /* low MDC */
                        miir &= ~MY_MASK_MIIR_MII_MDC;
                        CSR_WRITE_4(sc, MY_MANAGEMENT, miir);

                        /* read MDI */
                        miir = CSR_READ_4(sc, MY_MANAGEMENT);
                        if (miir & MY_MASK_MIIR_MII_MDI)
                                data |= mask;

                        /* high MDC, and wait */
                        miir |= MY_MASK_MIIR_MII_MDC;
                        CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
                        DELAY(30);

                        /* next */
                        mask >>= 1;
                }

                /* low MDC */
                miir &= ~MY_MASK_MIIR_MII_MDC;
                CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
        }

        return (u_int16_t) data;
}


static void
my_phy_writereg(struct my_softc * sc, int reg, int data)
{
        long            miir;
        int             mask;

        if (sc->my_info->my_did == MTD803ID)
                CSR_WRITE_2(sc, MY_PHYBASE + reg * 2, data);
        else {
                miir = my_send_cmd_to_phy(sc, MY_OP_WRITE, reg);

                /* write data */
                mask = 0x8000;
                while (mask) {
                        /* low MDC, prepare MDO */
                        miir &= ~(MY_MASK_MIIR_MII_MDC + MY_MASK_MIIR_MII_MDO);
                        if (mask & data)
                                miir |= MY_MASK_MIIR_MII_MDO;
                        CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
                        DELAY(1);

                        /* high MDC */
                        miir |= MY_MASK_MIIR_MII_MDC;
                        CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
                        DELAY(1);

                        /* next */
                        mask >>= 1;
                }

                /* low MDC */
                miir &= ~MY_MASK_MIIR_MII_MDC;
                CSR_WRITE_4(sc, MY_MANAGEMENT, miir);
        }
}

static          u_int8_t
my_calchash(caddr_t addr)
{
        u_int32_t       crc, carry;
        int             i, j;
        u_int8_t        c;

        /* Compute CRC for the address value. */
        crc = 0xFFFFFFFF;       /* initial value */

        for (i = 0; i < 6; i++) {
                c = *(addr + i);
                for (j = 0; j < 8; j++) {
                        carry = ((crc & 0x80000000) ? 1 : 0) ^ (c & 0x01);
                        crc <<= 1;
                        c >>= 1;
                        if (carry)
                                crc = (crc ^ 0x04c11db6) | carry;
                }
        }

        /*
         * return the filter bit position Note: I arrived at the following
         * nonsense through experimentation. It's not the usual way to
         * generate the bit position but it's the only thing I could come up
         * with that works.
         */
        return (~(crc >> 26) & 0x0000003F);
}


/*
 * Program the 64-bit multicast hash filter.
 */
static void
my_setmulti(struct my_softc * sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        int             h = 0;
        u_int32_t       hashes[2] = {0, 0};
        struct ifmultiaddr *ifma;
        u_int32_t       rxfilt;
        int             mcnt = 0;

        rxfilt = CSR_READ_4(sc, MY_TCRRCR);

        if (ifp->if_flags & IFF_ALLMULTI || ifp->if_flags & IFF_PROMISC) {
                rxfilt |= MY_AM;
                CSR_WRITE_4(sc, MY_TCRRCR, rxfilt);
                CSR_WRITE_4(sc, MY_MAR0, 0xFFFFFFFF);
                CSR_WRITE_4(sc, MY_MAR1, 0xFFFFFFFF);

                return;
        }
        /* first, zot all the existing hash bits */
        CSR_WRITE_4(sc, MY_MAR0, 0);
        CSR_WRITE_4(sc, MY_MAR1, 0);

        /* now program new ones */
        TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
                if (ifma->ifma_addr->sa_family != AF_LINK)
                        continue;
                h = my_calchash(LLADDR((struct sockaddr_dl *) ifma->ifma_addr));
                if (h < 32)
                        hashes[0] |= (1 << h);
                else
                        hashes[1] |= (1 << (h - 32));
                mcnt++;
        }

        if (mcnt)
                rxfilt |= MY_AM;
        else
                rxfilt &= ~MY_AM;
        CSR_WRITE_4(sc, MY_MAR0, hashes[0]);
        CSR_WRITE_4(sc, MY_MAR1, hashes[1]);
        CSR_WRITE_4(sc, MY_TCRRCR, rxfilt);
}

/*
 * Initiate an autonegotiation session.
 */
static void
my_autoneg_xmit(struct my_softc * sc)
{
        u_int16_t       phy_sts = 0;

        my_phy_writereg(sc, PHY_BMCR, PHY_BMCR_RESET);
        DELAY(500);
        while (my_phy_readreg(sc, PHY_BMCR) & PHY_BMCR_RESET);

        phy_sts = my_phy_readreg(sc, PHY_BMCR);
        phy_sts |= PHY_BMCR_AUTONEGENBL | PHY_BMCR_AUTONEGRSTR;
        my_phy_writereg(sc, PHY_BMCR, phy_sts);
}


/*
 * Invoke autonegotiation on a PHY.
 */
static void
my_autoneg_mii(struct my_softc * sc, int flag, int verbose)
{
        u_int16_t       phy_sts = 0, media, advert, ability;
        u_int16_t       ability2 = 0;
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct ifmedia *ifm = &sc->ifmedia;

        ifm->ifm_media = IFM_ETHER | IFM_AUTO;

#ifndef FORCE_AUTONEG_TFOUR
        /*
         * First, see if autoneg is supported. If not, there's no point in
         * continuing.
         */
        phy_sts = my_phy_readreg(sc, PHY_BMSR);
        if (!(phy_sts & PHY_BMSR_CANAUTONEG)) {
                if (verbose)
                        kprintf("my%d: autonegotiation not supported\n",
                            sc->my_unit);
                ifm->ifm_media = IFM_ETHER | IFM_10_T | IFM_HDX;
                return;
        }
#endif
        switch (flag) {
        case MY_FLAG_FORCEDELAY:
                /*
                 * XXX Never use this option anywhere but in the probe
                 * routine: making the kernel stop dead in its tracks for
                 * three whole seconds after we've gone multi-user is really
                 * bad manners.
                 */
                my_autoneg_xmit(sc);
                DELAY(5000000);
                break;
        case MY_FLAG_SCHEDDELAY:
                /*
                 * Wait for the transmitter to go idle before starting an
                 * autoneg session, otherwise my_start() may clobber our
                 * timeout, and we don't want to allow transmission during an
                 * autoneg session since that can screw it up.
                 */
                if (sc->my_cdata.my_tx_head != NULL) {
                        sc->my_want_auto = 1;
                        return;
                }
                my_autoneg_xmit(sc);
                ifp->if_timer = 5;
                sc->my_autoneg = 1;
                sc->my_want_auto = 0;
                return;
        case MY_FLAG_DELAYTIMEO:
                ifp->if_timer = 0;
                sc->my_autoneg = 0;
                break;
        default:
                kprintf("my%d: invalid autoneg flag: %d\n", sc->my_unit, flag);
                return;
        }

        if (my_phy_readreg(sc, PHY_BMSR) & PHY_BMSR_AUTONEGCOMP) {
                if (verbose)
                        kprintf("my%d: autoneg complete, ", sc->my_unit);
                phy_sts = my_phy_readreg(sc, PHY_BMSR);
        } else {
                if (verbose)
                        kprintf("my%d: autoneg not complete, ", sc->my_unit);
        }

        media = my_phy_readreg(sc, PHY_BMCR);

        /* Link is good. Report modes and set duplex mode. */
        if (my_phy_readreg(sc, PHY_BMSR) & PHY_BMSR_LINKSTAT) {
                if (verbose)
                        kprintf("my%d: link status good. ", sc->my_unit);
                advert = my_phy_readreg(sc, PHY_ANAR);
                ability = my_phy_readreg(sc, PHY_LPAR);
                if ((sc->my_pinfo->my_vid == MarvellPHYID0) ||
                    (sc->my_pinfo->my_vid == LevelOnePHYID0)) {
                        ability2 = my_phy_readreg(sc, PHY_1000SR);
                        if (ability2 & PHY_1000SR_1000BTXFULL) {
                                advert = 0;
                                ability = 0;
                                /*
                                 * this version did not support 1000M,
                                 * ifm->ifm_media =
                                 * IFM_ETHER | IFM_1000_T | IFM_FDX;
                                 */
                                ifm->ifm_media =
                                    IFM_ETHER | IFM_100_TX | IFM_FDX;
                                media &= ~PHY_BMCR_SPEEDSEL;
                                media |= PHY_BMCR_1000;
                                media |= PHY_BMCR_DUPLEX;
                                kprintf("(full-duplex, 1000Mbps)\n");
                        } else if (ability2 & PHY_1000SR_1000BTXHALF) {
                                advert = 0;
                                ability = 0;
                                /*
                                 * this version did not support 1000M,
                                 * ifm->ifm_media = IFM_ETHER | IFM_1000_T;
                                 */
                                ifm->ifm_media = IFM_ETHER | IFM_100_TX;
                                media &= ~PHY_BMCR_SPEEDSEL;
                                media &= ~PHY_BMCR_DUPLEX;
                                media |= PHY_BMCR_1000;
                                kprintf("(half-duplex, 1000Mbps)\n");
                        }
                }
                if (advert & PHY_ANAR_100BT4 && ability & PHY_ANAR_100BT4) {
                        ifm->ifm_media = IFM_ETHER | IFM_100_T4;
                        media |= PHY_BMCR_SPEEDSEL;
                        media &= ~PHY_BMCR_DUPLEX;
                        kprintf("(100baseT4)\n");
                } else if (advert & PHY_ANAR_100BTXFULL &&
                           ability & PHY_ANAR_100BTXFULL) {
                        ifm->ifm_media = IFM_ETHER | IFM_100_TX | IFM_FDX;
                        media |= PHY_BMCR_SPEEDSEL;
                        media |= PHY_BMCR_DUPLEX;
                        kprintf("(full-duplex, 100Mbps)\n");
                } else if (advert & PHY_ANAR_100BTXHALF &&
                           ability & PHY_ANAR_100BTXHALF) {
                        ifm->ifm_media = IFM_ETHER | IFM_100_TX | IFM_HDX;
                        media |= PHY_BMCR_SPEEDSEL;
                        media &= ~PHY_BMCR_DUPLEX;
                        kprintf("(half-duplex, 100Mbps)\n");
                } else if (advert & PHY_ANAR_10BTFULL &&
                           ability & PHY_ANAR_10BTFULL) {
                        ifm->ifm_media = IFM_ETHER | IFM_10_T | IFM_FDX;
                        media &= ~PHY_BMCR_SPEEDSEL;
                        media |= PHY_BMCR_DUPLEX;
                        kprintf("(full-duplex, 10Mbps)\n");
                } else if (advert) {
                        ifm->ifm_media = IFM_ETHER | IFM_10_T | IFM_HDX;
                        media &= ~PHY_BMCR_SPEEDSEL;
                        media &= ~PHY_BMCR_DUPLEX;
                        kprintf("(half-duplex, 10Mbps)\n");
                }
                media &= ~PHY_BMCR_AUTONEGENBL;

                /* Set ASIC's duplex mode to match the PHY. */
                my_phy_writereg(sc, PHY_BMCR, media);
                my_setcfg(sc, media);
        } else {
                if (verbose)
                        kprintf("my%d: no carrier\n", sc->my_unit);
        }

        my_init(sc);
        if (sc->my_tx_pend) {
                sc->my_autoneg = 0;
                sc->my_tx_pend = 0;
                if_devstart(ifp);
        }
}

/*
 * To get PHY ability.
 */
static void
my_getmode_mii(struct my_softc * sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        u_int16_t       bmsr;

        bmsr = my_phy_readreg(sc, PHY_BMSR);
        if (bootverbose)
                kprintf("my%d: PHY status word: %x\n", sc->my_unit, bmsr);

        /* fallback */
        sc->ifmedia.ifm_media = IFM_ETHER | IFM_10_T | IFM_HDX;

        if (bmsr & PHY_BMSR_10BTHALF) {
                if (bootverbose)
                        kprintf("my%d: 10Mbps half-duplex mode supported\n",
                               sc->my_unit);
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_10_T | IFM_HDX,
                    0, NULL);
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_10_T, 0, NULL);
        }
        if (bmsr & PHY_BMSR_10BTFULL) {
                if (bootverbose)
                        kprintf("my%d: 10Mbps full-duplex mode supported\n",
                            sc->my_unit);

                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_10_T | IFM_FDX,
                    0, NULL);
                sc->ifmedia.ifm_media = IFM_ETHER | IFM_10_T | IFM_FDX;
        }
        if (bmsr & PHY_BMSR_100BTXHALF) {
                if (bootverbose)
                        kprintf("my%d: 100Mbps half-duplex mode supported\n",
                               sc->my_unit);
                ifp->if_baudrate = 100000000;
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_100_TX, 0, NULL);
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_100_TX | IFM_HDX,
                            0, NULL);
                sc->ifmedia.ifm_media = IFM_ETHER | IFM_100_TX | IFM_HDX;
        }
        if (bmsr & PHY_BMSR_100BTXFULL) {
                if (bootverbose)
                        kprintf("my%d: 100Mbps full-duplex mode supported\n",
                            sc->my_unit);
                ifp->if_baudrate = 100000000;
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_100_TX | IFM_FDX,
                    0, NULL);
                sc->ifmedia.ifm_media = IFM_ETHER | IFM_100_TX | IFM_FDX;
        }
        /* Some also support 100BaseT4. */
        if (bmsr & PHY_BMSR_100BT4) {
                if (bootverbose)
                        kprintf("my%d: 100baseT4 mode supported\n", sc->my_unit);
                ifp->if_baudrate = 100000000;
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_100_T4, 0, NULL);
                sc->ifmedia.ifm_media = IFM_ETHER | IFM_100_T4;
#ifdef FORCE_AUTONEG_TFOUR
                if (bootverbose)
                        kprintf("my%d: forcing on autoneg support for BT4\n",
                            sc->my_unit);
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_AUTO, 0 NULL):
                sc->ifmedia.ifm_media = IFM_ETHER | IFM_AUTO;
#endif
        }
#if 0                           /* this version did not support 1000M, */
        if (sc->my_pinfo->my_vid == MarvellPHYID0) {
                if (bootverbose)
                        kprintf("my%d: 1000Mbps half-duplex mode supported\n",
                               sc->my_unit);

                ifp->if_baudrate = 1000000000;
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_1000_T, 0, NULL);
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_1000_T | IFM_HDX,
                    0, NULL);
                if (bootverbose)
                        kprintf("my%d: 1000Mbps full-duplex mode supported\n",
                           sc->my_unit);
                ifp->if_baudrate = 1000000000;
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_1000_T | IFM_FDX,
                    0, NULL);
                sc->ifmedia.ifm_media = IFM_ETHER | IFM_1000_T | IFM_FDX;
        }
#endif
        if (bmsr & PHY_BMSR_CANAUTONEG) {
                if (bootverbose)
                        kprintf("my%d: autoneg supported\n", sc->my_unit);
                ifmedia_add(&sc->ifmedia, IFM_ETHER | IFM_AUTO, 0, NULL);
                sc->ifmedia.ifm_media = IFM_ETHER | IFM_AUTO;
        }
}

/*
 * Set speed and duplex mode.
 */
static void
my_setmode_mii(struct my_softc * sc, int media)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        u_int16_t       bmcr;

        /*
         * If an autoneg session is in progress, stop it.
         */
        if (sc->my_autoneg) {
                kprintf("my%d: canceling autoneg session\n", sc->my_unit);
                ifp->if_timer = sc->my_autoneg = sc->my_want_auto = 0;
                bmcr = my_phy_readreg(sc, PHY_BMCR);
                bmcr &= ~PHY_BMCR_AUTONEGENBL;
                my_phy_writereg(sc, PHY_BMCR, bmcr);
        }
        kprintf("my%d: selecting MII, ", sc->my_unit);
        bmcr = my_phy_readreg(sc, PHY_BMCR);
        bmcr &= ~(PHY_BMCR_AUTONEGENBL | PHY_BMCR_SPEEDSEL | PHY_BMCR_1000 |
                  PHY_BMCR_DUPLEX | PHY_BMCR_LOOPBK);

#if 0                           /* this version did not support 1000M, */
        if (IFM_SUBTYPE(media) == IFM_1000_T) {
                kprintf("1000Mbps/T4, half-duplex\n");
                bmcr &= ~PHY_BMCR_SPEEDSEL;
                bmcr &= ~PHY_BMCR_DUPLEX;
                bmcr |= PHY_BMCR_1000;
        }
#endif
        if (IFM_SUBTYPE(media) == IFM_100_T4) {
                kprintf("100Mbps/T4, half-duplex\n");
                bmcr |= PHY_BMCR_SPEEDSEL;
                bmcr &= ~PHY_BMCR_DUPLEX;
        }
        if (IFM_SUBTYPE(media) == IFM_100_TX) {
                kprintf("100Mbps, ");
                bmcr |= PHY_BMCR_SPEEDSEL;
        }
        if (IFM_SUBTYPE(media) == IFM_10_T) {
                kprintf("10Mbps, ");
                bmcr &= ~PHY_BMCR_SPEEDSEL;
        }
        if ((media & IFM_GMASK) == IFM_FDX) {
                kprintf("full duplex\n");
                bmcr |= PHY_BMCR_DUPLEX;
        } else {
                kprintf("half duplex\n");
                bmcr &= ~PHY_BMCR_DUPLEX;
        }
        my_phy_writereg(sc, PHY_BMCR, bmcr);
        my_setcfg(sc, bmcr);
}

/*
 * The Myson manual states that in order to fiddle with the 'full-duplex' and
 * '100Mbps' bits in the netconfig register, we first have to put the
 * transmit and/or receive logic in the idle state.
 */
static void
my_setcfg(struct my_softc * sc, int bmcr)
{
        int             i, restart = 0;

        if (CSR_READ_4(sc, MY_TCRRCR) & (MY_TE | MY_RE)) {
                restart = 1;
                MY_CLRBIT(sc, MY_TCRRCR, (MY_TE | MY_RE));
                for (i = 0; i < MY_TIMEOUT; i++) {
                        DELAY(10);
                        if (!(CSR_READ_4(sc, MY_TCRRCR) &
                            (MY_TXRUN | MY_RXRUN)))
                                break;
                }
                if (i == MY_TIMEOUT)
                        kprintf("my%d: failed to force tx and rx to idle \n",
                            sc->my_unit);
        }
        MY_CLRBIT(sc, MY_TCRRCR, MY_PS1000);
        MY_CLRBIT(sc, MY_TCRRCR, MY_PS10);
        if (bmcr & PHY_BMCR_1000)
                MY_SETBIT(sc, MY_TCRRCR, MY_PS1000);
        else if (!(bmcr & PHY_BMCR_SPEEDSEL))
                MY_SETBIT(sc, MY_TCRRCR, MY_PS10);
        if (bmcr & PHY_BMCR_DUPLEX)
                MY_SETBIT(sc, MY_TCRRCR, MY_FD);
        else
                MY_CLRBIT(sc, MY_TCRRCR, MY_FD);
        if (restart)
                MY_SETBIT(sc, MY_TCRRCR, MY_TE | MY_RE);
}

static void
my_reset(struct my_softc * sc)
{
        int    i;

        MY_SETBIT(sc, MY_BCR, MY_SWR);
        for (i = 0; i < MY_TIMEOUT; i++) {
                DELAY(10);
                if (!(CSR_READ_4(sc, MY_BCR) & MY_SWR))
                        break;
        }
        if (i == MY_TIMEOUT)
                kprintf("m0x%d: reset never completed!\n", sc->my_unit);

        /* Wait a little while for the chip to get its brains in order. */
        DELAY(1000);
}

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

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

        for (t = my_devs; t->my_name != NULL; t++) {
                if (vendor == t->my_vid && product == t->my_did) {
                        device_set_desc(dev, t->my_name);
                        return (0);
                }
        }

        return (ENXIO);
}

/*
 * Attach the interface. Allocate softc structures, do ifmedia setup and
 * ethernet/BPF attach.
 */
static int
my_attach(device_t dev)
{
        int             i;
        u_char          eaddr[ETHER_ADDR_LEN];
        u_int32_t       command, iobase;
        struct my_softc *sc;
        struct ifnet   *ifp;
        int             media = IFM_ETHER | IFM_100_TX | IFM_FDX;
        unsigned int    round;
        caddr_t         roundptr;
        struct my_type *p;
        u_int16_t       phy_vid, phy_did, phy_sts = 0;
        int             rid, unit, error = 0;
        struct my_type *t;
        uint16_t vendor, product;

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

        for (t = my_devs; t->my_name != NULL; t++) {
                if (vendor == t->my_vid && product == t->my_did)
                        break;
        }

        if (t->my_name == NULL)
                return(ENXIO);

        sc = device_get_softc(dev);
        unit = device_get_unit(dev);

        /*
         * Map control/status registers.
         */
        command = pci_read_config(dev, PCIR_COMMAND, 4);
        command |= (PCIM_CMD_PORTEN | PCIM_CMD_MEMEN | PCIM_CMD_BUSMASTEREN);
        pci_write_config(dev, PCIR_COMMAND, command & 0x000000ff, 4);
        command = pci_read_config(dev, PCIR_COMMAND, 4);

        if (t->my_did == MTD800ID) {
                iobase = pci_read_config(dev, MY_PCI_LOIO, 4);
                if (iobase & 0x300)
                        MY_USEIOSPACE = 0;
        }
        if (MY_USEIOSPACE) {
                if (!(command & PCIM_CMD_PORTEN)) {
                        kprintf("my%d: failed to enable I/O ports!\n", unit);
                        error = ENXIO;
                        return(error);
                }
        } else {
                if (!(command & PCIM_CMD_MEMEN)) {
                        kprintf("my%d: failed to enable memory mapping!\n",
                            unit);
                        error = ENXIO;
                        return(error);
                }
        }

        rid = MY_RID;
        sc->my_res = bus_alloc_resource_any(dev, MY_RES, &rid, RF_ACTIVE);

        if (sc->my_res == NULL) {
                kprintf("my%d: couldn't map ports/memory\n", unit);
                error = ENXIO;
                goto fail;
        }
        sc->my_btag = rman_get_bustag(sc->my_res);
        sc->my_bhandle = rman_get_bushandle(sc->my_res);

        rid = 0;
        sc->my_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
            RF_SHAREABLE | RF_ACTIVE);

        if (sc->my_irq == NULL) {
                kprintf("my%d: couldn't map interrupt\n", unit);
                error = ENXIO;
                goto fail;
        }

        sc->my_info = t;

        /* Reset the adapter. */
        my_reset(sc);

        /*
         * Get station address
         */
        for (i = 0; i < ETHER_ADDR_LEN; ++i)
                eaddr[i] = CSR_READ_1(sc, MY_PAR0 + i);

        sc->my_unit = unit;

        sc->my_ldata_ptr = kmalloc(sizeof(struct my_list_data) + 8,
                                  M_DEVBUF, M_WAITOK);
        sc->my_ldata = (struct my_list_data *) sc->my_ldata_ptr;
        round = (uintptr_t)sc->my_ldata_ptr & 0xF;
        roundptr = sc->my_ldata_ptr;
        for (i = 0; i < 8; i++) {
                if (round % 8) {
                        round++;
                        roundptr++;
                } else
                        break;
        }
        sc->my_ldata = (struct my_list_data *) roundptr;
        bzero(sc->my_ldata, sizeof(struct my_list_data));

        ifp = &sc->arpcom.ac_if;
        ifp->if_softc = sc;
        if_initname(ifp, "my", unit);
        ifp->if_mtu = ETHERMTU;
        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_ioctl = my_ioctl;
        ifp->if_start = my_start;
        ifp->if_watchdog = my_watchdog;
        ifp->if_init = my_init;
        ifp->if_baudrate = 10000000;
        ifq_set_maxlen(&ifp->if_snd, IFQ_MAXLEN);
        ifq_set_ready(&ifp->if_snd);

        if (sc->my_info->my_did == MTD803ID)
                sc->my_pinfo = my_phys;
        else {
                if (bootverbose)
                        kprintf("my%d: probing for a PHY\n", sc->my_unit);
                for (i = MY_PHYADDR_MIN; i < MY_PHYADDR_MAX + 1; i++) {
                        if (bootverbose)
                                kprintf("my%d: checking address: %d\n",
                                    sc->my_unit, i);
                        sc->my_phy_addr = i;
                        phy_sts = my_phy_readreg(sc, PHY_BMSR);
                        if ((phy_sts != 0) && (phy_sts != 0xffff))
                                break;
                        else
                                phy_sts = 0;
                }
                if (phy_sts) {
                        phy_vid = my_phy_readreg(sc, PHY_VENID);
                        phy_did = my_phy_readreg(sc, PHY_DEVID);
                        if (bootverbose) {
                                kprintf("my%d: found PHY at address %d, ",
                                    sc->my_unit, sc->my_phy_addr);
                                kprintf("vendor id: %x device id: %x\n",
                                    phy_vid, phy_did);
                        }
                        p = my_phys;
                        while (p->my_vid) {
                                if (phy_vid == p->my_vid) {
                                        sc->my_pinfo = p;
                                        break;
                                }
                                p++;
                        }
                        if (sc->my_pinfo == NULL)
                                sc->my_pinfo = &my_phys[PHY_UNKNOWN];
                        if (bootverbose)
                                kprintf("my%d: PHY type: %s\n",
                                       sc->my_unit, sc->my_pinfo->my_name);
                } else {
                        kprintf("my%d: MII without any phy!\n", sc->my_unit);
                        error = ENXIO;
                        goto fail;
                }
        }

        /* Do ifmedia setup. */
        ifmedia_init(&sc->ifmedia, 0, my_ifmedia_upd, my_ifmedia_sts);
        my_getmode_mii(sc);
        my_autoneg_mii(sc, MY_FLAG_FORCEDELAY, 1);
        media = sc->ifmedia.ifm_media;
        my_stop(sc);
        ifmedia_set(&sc->ifmedia, media);

        ether_ifattach(ifp, eaddr, NULL);

        ifq_set_cpuid(&ifp->if_snd, rman_get_cpuid(sc->my_irq));

        error = bus_setup_intr(dev, sc->my_irq, INTR_MPSAFE,
                               my_intr, sc, &sc->my_intrhand, 
                               ifp->if_serializer);
        if (error) {
                ether_ifdetach(ifp);
                kprintf("my%d: couldn't set up irq\n", unit);
                goto fail;
        }

        return (0);

fail:
        my_detach(dev);
        return (error);
}

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

        if (device_is_attached(dev)) {
                lwkt_serialize_enter(ifp->if_serializer);
                my_stop(sc);
                bus_teardown_intr(dev, sc->my_irq, sc->my_intrhand);
                lwkt_serialize_exit(ifp->if_serializer);

                ether_ifdetach(ifp);
        }

        if (sc->my_irq)
                bus_release_resource(dev, SYS_RES_IRQ, 0, sc->my_irq);
        if (sc->my_res)
                bus_release_resource(dev, MY_RES, MY_RID, sc->my_res);

        return (0);
}


/*
 * Initialize the transmit descriptors.
 */
static int
my_list_tx_init(struct my_softc * sc)
{
        struct my_chain_data *cd;
        struct my_list_data *ld;
        int             i;

        cd = &sc->my_cdata;
        ld = sc->my_ldata;
        for (i = 0; i < MY_TX_LIST_CNT; i++) {
                cd->my_tx_chain[i].my_ptr = &ld->my_tx_list[i];
                if (i == (MY_TX_LIST_CNT - 1))
                        cd->my_tx_chain[i].my_nextdesc = &cd->my_tx_chain[0];
                else
                        cd->my_tx_chain[i].my_nextdesc =
                            &cd->my_tx_chain[i + 1];
        }
        cd->my_tx_free = &cd->my_tx_chain[0];
        cd->my_tx_tail = cd->my_tx_head = NULL;
        return (0);
}

/*
 * Initialize the RX descriptors and allocate mbufs for them. Note that we
 * arrange the descriptors in a closed ring, so that the last descriptor
 * points back to the first.
 */
static int
my_list_rx_init(struct my_softc * sc)
{
        struct my_chain_data *cd;
        struct my_list_data *ld;
        int             i;

        cd = &sc->my_cdata;
        ld = sc->my_ldata;
        for (i = 0; i < MY_RX_LIST_CNT; i++) {
                cd->my_rx_chain[i].my_ptr =
                    (struct my_desc *) & ld->my_rx_list[i];
                if (my_newbuf(sc, &cd->my_rx_chain[i]) == ENOBUFS)
                        return (ENOBUFS);
                if (i == (MY_RX_LIST_CNT - 1)) {
                        cd->my_rx_chain[i].my_nextdesc = &cd->my_rx_chain[0];
                        ld->my_rx_list[i].my_next = vtophys(&ld->my_rx_list[0]);
                } else {
                        cd->my_rx_chain[i].my_nextdesc =
                            &cd->my_rx_chain[i + 1];
                        ld->my_rx_list[i].my_next =
                            vtophys(&ld->my_rx_list[i + 1]);
                }
        }
        cd->my_rx_head = &cd->my_rx_chain[0];
        return (0);
}

/*
 * Initialize an RX descriptor and attach an MBUF cluster.
 */
static int
my_newbuf(struct my_softc * sc, struct my_chain_onefrag * c)
{
        struct mbuf    *m_new = NULL;

        MGETHDR(m_new, M_NOWAIT, MT_DATA);
        if (m_new == NULL) {
                kprintf("my%d: no memory for rx list -- packet dropped!\n",
                       sc->my_unit);
                return (ENOBUFS);
        }
        MCLGET(m_new, M_NOWAIT);
        if (!(m_new->m_flags & M_EXT)) {
                kprintf("my%d: no memory for rx list -- packet dropped!\n",
                       sc->my_unit);
                m_freem(m_new);
                return (ENOBUFS);
        }
        c->my_mbuf = m_new;
        c->my_ptr->my_data = vtophys(mtod(m_new, caddr_t));
        c->my_ptr->my_ctl = (MCLBYTES - 1) << MY_RBSShift;
        c->my_ptr->my_status = MY_OWNByNIC;
        return (0);
}

/*
 * A frame has been uploaded: pass the resulting mbuf chain up to the higher
 * level protocols.
 */
static void
my_rxeof(struct my_softc * sc)
{
        struct mbuf *m;
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct my_chain_onefrag *cur_rx;
        int total_len = 0;
        u_int32_t rxstat;

        while (!((rxstat = sc->my_cdata.my_rx_head->my_ptr->my_status)
            & MY_OWNByNIC)) {
                cur_rx = sc->my_cdata.my_rx_head;
                sc->my_cdata.my_rx_head = cur_rx->my_nextdesc;

                if (rxstat & MY_ES) {   /* error summary: give up this rx pkt */
                        IFNET_STAT_INC(ifp, ierrors, 1);
                        cur_rx->my_ptr->my_status = MY_OWNByNIC;
                        continue;
                }
                /* No errors; receive the packet. */
                total_len = (rxstat & MY_FLNGMASK) >> MY_FLNGShift;
                total_len -= ETHER_CRC_LEN;

                if (total_len < MINCLSIZE) {
                        m = m_devget(mtod(cur_rx->my_mbuf, void *),
                                     total_len, 0, ifp);
                        cur_rx->my_ptr->my_status = MY_OWNByNIC;
                        if (m == NULL) {
                                IFNET_STAT_INC(ifp, ierrors, 1);
                                continue;
                        }
                } else {
                        m = cur_rx->my_mbuf;
                        /*
                         * Try to conjure up a new mbuf cluster. If that
                         * fails, it means we have an out of memory condition
                         * and should leave the buffer in place and continue.
                         * This will result in a lost packet, but there's
                         * little else we can do in this situation.
                         */
                        if (my_newbuf(sc, cur_rx) == ENOBUFS) {
                                IFNET_STAT_INC(ifp, ierrors, 1);
                                cur_rx->my_ptr->my_status = MY_OWNByNIC;
                                continue;
                        }
                        m->m_pkthdr.rcvif = ifp;
                        m->m_pkthdr.len = m->m_len = total_len;
                }
                IFNET_STAT_INC(ifp, ipackets, 1);
                ifp->if_input(ifp, m, NULL, -1);
        }
}


/*
 * A frame was downloaded to the chip. It's safe for us to clean up the list
 * buffers.
 */
static void
my_txeof(struct my_softc * sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct my_chain *cur_tx;

        /* Clear the timeout timer. */
        ifp->if_timer = 0;
        if (sc->my_cdata.my_tx_head == NULL)
                return;
        /*
         * Go through our tx list and free mbufs for those frames that have
         * been transmitted.
         */
        while (sc->my_cdata.my_tx_head->my_mbuf != NULL) {
                u_int32_t       txstat;

                cur_tx = sc->my_cdata.my_tx_head;
                txstat = MY_TXSTATUS(cur_tx);
                if ((txstat & MY_OWNByNIC) || txstat == MY_UNSENT)
                        break;
                if (!(CSR_READ_4(sc, MY_TCRRCR) & MY_Enhanced)) {
                        if (txstat & MY_TXERR) {
                                IFNET_STAT_INC(ifp, oerrors, 1);
                                if (txstat & MY_EC) /* excessive collision */
                                        IFNET_STAT_INC(ifp, collisions, 1);
                                if (txstat & MY_LC)     /* late collision */
                                        IFNET_STAT_INC(ifp, collisions, 1);
                        }
                        IFNET_STAT_INC(ifp, collisions,
                            (txstat & MY_NCRMASK) >> MY_NCRShift);
                }
                IFNET_STAT_INC(ifp, opackets, 1);
                m_freem(cur_tx->my_mbuf);
                cur_tx->my_mbuf = NULL;
                if (sc->my_cdata.my_tx_head == sc->my_cdata.my_tx_tail) {
                        sc->my_cdata.my_tx_head = NULL;
                        sc->my_cdata.my_tx_tail = NULL;
                        break;
                }
                sc->my_cdata.my_tx_head = cur_tx->my_nextdesc;
        }
        if (CSR_READ_4(sc, MY_TCRRCR) & MY_Enhanced) {
                IFNET_STAT_INC(ifp, collisions,
                    (CSR_READ_4(sc, MY_TSR) & MY_NCRMask));
        }
}

/*
 * TX 'end of channel' interrupt handler.
 */
static void
my_txeoc(struct my_softc * sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;

        ifp->if_timer = 0;
        if (sc->my_cdata.my_tx_head == NULL) {
                ifq_clr_oactive(&ifp->if_snd);
                sc->my_cdata.my_tx_tail = NULL;
                if (sc->my_want_auto)
                        my_autoneg_mii(sc, MY_FLAG_SCHEDDELAY, 1);
        } else {
                if (MY_TXOWN(sc->my_cdata.my_tx_head) == MY_UNSENT) {
                        MY_TXOWN(sc->my_cdata.my_tx_head) = MY_OWNByNIC;
                        ifp->if_timer = 5;
                        CSR_WRITE_4(sc, MY_TXPDR, 0xFFFFFFFF);
                }
        }
}

static void
my_intr(void *arg)
{
        struct my_softc *sc = arg;
        struct ifnet *ifp = &sc->arpcom.ac_if;
        u_int32_t status;

        if (!(ifp->if_flags & IFF_UP))
                return;

        /* Disable interrupts. */
        CSR_WRITE_4(sc, MY_IMR, 0x00000000);

        for (;;) {
                status = CSR_READ_4(sc, MY_ISR);
                status &= MY_INTRS;
                if (status)
                        CSR_WRITE_4(sc, MY_ISR, status);
                else
                        break;

                if (status & MY_RI)     /* receive interrupt */
                        my_rxeof(sc);

                if ((status & MY_RBU) || (status & MY_RxErr)) {
                        /* rx buffer unavailable or rx error */
                        IFNET_STAT_INC(ifp, ierrors, 1);
#ifdef foo
                        my_stop(sc);
                        my_reset(sc);
                        my_init(sc);
#endif
                }
                if (status & MY_TI)     /* tx interrupt */
                        my_txeof(sc);
                if (status & MY_ETI)    /* tx early interrupt */
                        my_txeof(sc);
                if (status & MY_TBU)    /* tx buffer unavailable */
                        my_txeoc(sc);

#if 0                           /* 90/1/18 delete */
                if (status & MY_FBE) {
                        my_reset(sc);
                        my_init(sc);
                }
#endif

        }

        /* Re-enable interrupts. */
        CSR_WRITE_4(sc, MY_IMR, MY_INTRS);
        if (!ifq_is_empty(&ifp->if_snd))
                if_devstart(ifp);
}

/*
 * Encapsulate an mbuf chain in a descriptor by coupling the mbuf data
 * pointers to the fragment pointers.
 */
static int
my_encap(struct my_softc * sc, struct my_chain * c, struct mbuf * m_head)
{
        struct my_desc *f = NULL;
        int             total_len;
        struct mbuf    *m, *m_new = NULL;

        /* calculate the total tx pkt length */
        total_len = 0;
        for (m = m_head; m != NULL; m = m->m_next)
                total_len += m->m_len;
        /*
         * 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.
         */
        m = m_head;
        MGETHDR(m_new, M_NOWAIT, MT_DATA);
        if (m_new == NULL) {
                kprintf("my%d: no memory for tx list", sc->my_unit);
                return (1);
        }
        if (m_head->m_pkthdr.len > MHLEN) {
                MCLGET(m_new, M_NOWAIT);
                if (!(m_new->m_flags & M_EXT)) {
                        m_freem(m_new);
                        kprintf("my%d: no memory for tx list", sc->my_unit);
                        return (1);
                }
        }
        m_copydata(m_head, 0, m_head->m_pkthdr.len, mtod(m_new, void *));
        m_new->m_pkthdr.len = m_new->m_len = m_head->m_pkthdr.len;
        m_freem(m_head);
        m_head = m_new;
        f = &c->my_ptr->my_frag[0];
        f->my_status = 0;
        f->my_data = vtophys(mtod(m_new, caddr_t));
        total_len = m_new->m_len;
        f->my_ctl = MY_TXFD | MY_TXLD | MY_CRCEnable | MY_PADEnable;
        f->my_ctl |= total_len << MY_PKTShift;  /* pkt size */
        f->my_ctl |= total_len; /* buffer size */
        /* 89/12/29 add, for mtd891 *//* [ 89? ] */
        if (sc->my_info->my_did == MTD891ID)
                f->my_ctl |= MY_ETIControl | MY_RetryTxLC;
        c->my_mbuf = m_head;
        c->my_lastdesc = 0;
        MY_TXNEXT(c) = vtophys(&c->my_nextdesc->my_ptr->my_frag[0]);
        return (0);
}

/*
 * Main transmit routine. To avoid having to do mbuf copies, we put pointers
 * to the mbuf data regions directly in the transmit lists. We also save a
 * copy of the pointers since the transmit list fragment pointers are
 * physical addresses.
 */
static void
my_start(struct ifnet * ifp, struct ifaltq_subque *ifsq)
{
        struct my_softc *sc = ifp->if_softc;
        struct mbuf    *m_head = NULL;
        struct my_chain *cur_tx = NULL, *start_tx;

        ASSERT_ALTQ_SQ_DEFAULT(ifp, ifsq);
        crit_enter();

        if (sc->my_autoneg) {
                ifq_purge(&ifp->if_snd);
                sc->my_tx_pend = 1;
                crit_exit();
                return;
        }
        /*
         * Check for an available queue slot. If there are none, punt.
         */
        if (sc->my_cdata.my_tx_free->my_mbuf != NULL) {
                ifq_set_oactive(&ifp->if_snd);
                crit_exit();
                return;
        }

        start_tx = sc->my_cdata.my_tx_free;
        while (sc->my_cdata.my_tx_free->my_mbuf == NULL) {
                m_head = ifq_dequeue(&ifp->if_snd);
                if (m_head == NULL)
                        break;

                /* Pick a descriptor off the free list. */
                cur_tx = sc->my_cdata.my_tx_free;
                sc->my_cdata.my_tx_free = cur_tx->my_nextdesc;

                /* Pack the data into the descriptor. */
                my_encap(sc, cur_tx, m_head);

                if (cur_tx != start_tx)
                        MY_TXOWN(cur_tx) = MY_OWNByNIC;
                BPF_MTAP(ifp, cur_tx->my_mbuf);
        }
        /*
         * If there are no packets queued, bail.
         */
        if (cur_tx == NULL) {
                crit_exit();
                return;
        }
        /*
         * Place the request for the upload interrupt in the last descriptor
         * in the chain. This way, if we're chaining several packets at once,
         * we'll only get an interupt once for the whole chain rather than
         * once for each packet.
         */
        MY_TXCTL(cur_tx) |= MY_TXIC;
        cur_tx->my_ptr->my_frag[0].my_ctl |= MY_TXIC;
        sc->my_cdata.my_tx_tail = cur_tx;
        if (sc->my_cdata.my_tx_head == NULL)
                sc->my_cdata.my_tx_head = start_tx;
        MY_TXOWN(start_tx) = MY_OWNByNIC;
        CSR_WRITE_4(sc, MY_TXPDR, 0xFFFFFFFF);  /* tx polling demand */

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

        crit_exit();
}

static void
my_init(void *xsc)
{
        struct my_softc *sc = xsc;
        struct ifnet   *ifp = &sc->arpcom.ac_if;
        u_int16_t       phy_bmcr = 0;

        crit_enter();
        if (sc->my_autoneg) {
                crit_exit();
                return;
        }
        if (sc->my_pinfo != NULL)
                phy_bmcr = my_phy_readreg(sc, PHY_BMCR);
        /*
         * Cancel pending I/O and free all RX/TX buffers.
         */
        my_stop(sc);
        my_reset(sc);

        /*
         * Set cache alignment and burst length.
         */
#if 0                           /* 89/9/1 modify,  */
        CSR_WRITE_4(sc, MY_BCR, MY_RPBLE512);
        CSR_WRITE_4(sc, MY_TCRRCR, MY_TFTSF);
#endif
        CSR_WRITE_4(sc, MY_BCR, MY_PBL8);
        CSR_WRITE_4(sc, MY_TCRRCR, MY_TFTSF | MY_RBLEN | MY_RPBLE512);
        /*
         * 89/12/29 add, for mtd891,
         */
        if (sc->my_info->my_did == MTD891ID) {
                MY_SETBIT(sc, MY_BCR, MY_PROG);
                MY_SETBIT(sc, MY_TCRRCR, MY_Enhanced);
        }
        my_setcfg(sc, phy_bmcr);
        /* Init circular RX list. */
        if (my_list_rx_init(sc) == ENOBUFS) {
                kprintf("my%d: init failed: no memory for rx buffers\n",
                    sc->my_unit);
                my_stop(sc);
                crit_exit();
                return;
        }
        /* Init TX descriptors. */
        my_list_tx_init(sc);

        /* If we want promiscuous mode, set the allframes bit. */
        if (ifp->if_flags & IFF_PROMISC)
                MY_SETBIT(sc, MY_TCRRCR, MY_PROM);
        else
                MY_CLRBIT(sc, MY_TCRRCR, MY_PROM);

        /*
         * Set capture broadcast bit to capture broadcast frames.
         */
        if (ifp->if_flags & IFF_BROADCAST)
                MY_SETBIT(sc, MY_TCRRCR, MY_AB);
        else
                MY_CLRBIT(sc, MY_TCRRCR, MY_AB);

        /*
         * Program the multicast filter, if necessary.
         */
        my_setmulti(sc);

        /*
         * Load the address of the RX list.
         */
        MY_CLRBIT(sc, MY_TCRRCR, MY_RE);
        CSR_WRITE_4(sc, MY_RXLBA, vtophys(&sc->my_ldata->my_rx_list[0]));

        /*
         * Enable interrupts.
         */
        CSR_WRITE_4(sc, MY_IMR, MY_INTRS);
        CSR_WRITE_4(sc, MY_ISR, 0xFFFFFFFF);

        /* Enable receiver and transmitter. */
        MY_SETBIT(sc, MY_TCRRCR, MY_RE);
        MY_CLRBIT(sc, MY_TCRRCR, MY_TE);
        CSR_WRITE_4(sc, MY_TXLBA, vtophys(&sc->my_ldata->my_tx_list[0]));
        MY_SETBIT(sc, MY_TCRRCR, MY_TE);

        /* Restore state of BMCR */
        if (sc->my_pinfo != NULL)
                my_phy_writereg(sc, PHY_BMCR, phy_bmcr);
        ifp->if_flags |= IFF_RUNNING;
        ifq_clr_oactive(&ifp->if_snd);
        crit_exit();
}

/*
 * Set media options.
 */

static int
my_ifmedia_upd(struct ifnet * ifp)
{
        struct my_softc *sc = ifp->if_softc;
        struct ifmedia *ifm = &sc->ifmedia;

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

        crit_enter();

        if (IFM_SUBTYPE(ifm->ifm_media) == IFM_AUTO)
                my_autoneg_mii(sc, MY_FLAG_SCHEDDELAY, 1);
        else
                my_setmode_mii(sc, ifm->ifm_media);

        crit_exit();

        return (0);
}

/*
 * Report current media status.
 */

static void
my_ifmedia_sts(struct ifnet * ifp, struct ifmediareq * ifmr)
{
        struct my_softc *sc = ifp->if_softc;
        u_int16_t advert = 0, ability = 0;

        crit_enter();

        ifmr->ifm_active = IFM_ETHER;
        if (!(my_phy_readreg(sc, PHY_BMCR) & PHY_BMCR_AUTONEGENBL)) {
#if 0                           /* this version did not support 1000M, */
                if (my_phy_readreg(sc, PHY_BMCR) & PHY_BMCR_1000)
                        ifmr->ifm_active = IFM_ETHER | IFM_1000TX;
#endif
                if (my_phy_readreg(sc, PHY_BMCR) & PHY_BMCR_SPEEDSEL)
                        ifmr->ifm_active = IFM_ETHER | IFM_100_TX;
                else
                        ifmr->ifm_active = IFM_ETHER | IFM_10_T;
                if (my_phy_readreg(sc, PHY_BMCR) & PHY_BMCR_DUPLEX)
                        ifmr->ifm_active |= IFM_FDX;
                else
                        ifmr->ifm_active |= IFM_HDX;

                crit_exit();

                return;
        }
        ability = my_phy_readreg(sc, PHY_LPAR);
        advert = my_phy_readreg(sc, PHY_ANAR);

#if 0                           /* this version did not support 1000M, */
        if (sc->my_pinfo->my_vid == MarvellPHYID0) {
                ability2 = my_phy_readreg(sc, PHY_1000SR);
                if (ability2 & PHY_1000SR_1000BTXFULL) {
                        advert = 0;
                        ability = 0;
                        ifmr->ifm_active = IFM_ETHER | IFM_1000_T | IFM_FDX;
                } else if (ability & PHY_1000SR_1000BTXHALF) {
                        advert = 0;
                        ability = 0;
                        ifmr->ifm_active = IFM_ETHER | IFM_1000_T | IFM_HDX;
                }
        }
#endif
        if (advert & PHY_ANAR_100BT4 && ability & PHY_ANAR_100BT4)
                ifmr->ifm_active = IFM_ETHER | IFM_100_T4;
        else if (advert & PHY_ANAR_100BTXFULL && ability & PHY_ANAR_100BTXFULL)
                ifmr->ifm_active = IFM_ETHER | IFM_100_TX | IFM_FDX;
        else if (advert & PHY_ANAR_100BTXHALF && ability & PHY_ANAR_100BTXHALF)
                ifmr->ifm_active = IFM_ETHER | IFM_100_TX | IFM_HDX;
        else if (advert & PHY_ANAR_10BTFULL && ability & PHY_ANAR_10BTFULL)
                ifmr->ifm_active = IFM_ETHER | IFM_10_T | IFM_FDX;
        else if (advert & PHY_ANAR_10BTHALF && ability & PHY_ANAR_10BTHALF)
                ifmr->ifm_active = IFM_ETHER | IFM_10_T | IFM_HDX;

        crit_exit();
}

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

        crit_enter();
        switch (command) {
        case SIOCSIFFLAGS:
                if (ifp->if_flags & IFF_UP)
                        my_init(sc);
                else if (ifp->if_flags & IFF_RUNNING)
                        my_stop(sc);
                error = 0;
                break;
        case SIOCADDMULTI:
        case SIOCDELMULTI:
                my_setmulti(sc);
                error = 0;
                break;
        case SIOCGIFMEDIA:
        case SIOCSIFMEDIA:
                error = ifmedia_ioctl(ifp, ifr, &sc->ifmedia, command);
                break;
        default:
                error = ether_ioctl(ifp, command, data);
                break;
        }

        crit_exit();
        return (error);
}

static void
my_watchdog(struct ifnet * ifp)
{
        struct my_softc *sc = ifp->if_softc;

        crit_enter();

        if (sc->my_autoneg) {
                my_autoneg_mii(sc, MY_FLAG_DELAYTIMEO, 1);
                crit_exit();
                return;
        }
        IFNET_STAT_INC(ifp, oerrors, 1);
        kprintf("my%d: watchdog timeout\n", sc->my_unit);
        if (!(my_phy_readreg(sc, PHY_BMSR) & PHY_BMSR_LINKSTAT))
                kprintf("my%d: no carrier - transceiver cable problem?\n",
                    sc->my_unit);
        my_stop(sc);
        my_reset(sc);
        my_init(sc);
        if (!ifq_is_empty(&ifp->if_snd))
                if_devstart(ifp);
        crit_exit();
}


/*
 * Stop the adapter and free any mbufs allocated to the RX and TX lists.
 */
static void
my_stop(struct my_softc * sc)
{
        struct ifnet *ifp = &sc->arpcom.ac_if;
        int    i;

        ifp->if_timer = 0;

        MY_CLRBIT(sc, MY_TCRRCR, (MY_RE | MY_TE));
        CSR_WRITE_4(sc, MY_IMR, 0x00000000);
        CSR_WRITE_4(sc, MY_TXLBA, 0x00000000);
        CSR_WRITE_4(sc, MY_RXLBA, 0x00000000);

        /*
         * Free data in the RX lists.
         */
        for (i = 0; i < MY_RX_LIST_CNT; i++) {
                if (sc->my_cdata.my_rx_chain[i].my_mbuf != NULL) {
                        m_freem(sc->my_cdata.my_rx_chain[i].my_mbuf);
                        sc->my_cdata.my_rx_chain[i].my_mbuf = NULL;
                }
        }
        bzero((char *)&sc->my_ldata->my_rx_list,
            sizeof(sc->my_ldata->my_rx_list));
        /*
         * Free the TX list buffers.
         */
        for (i = 0; i < MY_TX_LIST_CNT; i++) {
                if (sc->my_cdata.my_tx_chain[i].my_mbuf != NULL) {
                        m_freem(sc->my_cdata.my_tx_chain[i].my_mbuf);
                        sc->my_cdata.my_tx_chain[i].my_mbuf = NULL;
                }
        }
        bzero((char *)&sc->my_ldata->my_tx_list,
            sizeof(sc->my_ldata->my_tx_list));
        ifp->if_flags &= ~IFF_RUNNING;
        ifq_clr_oactive(&ifp->if_snd);
}

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

        sc = device_get_softc(dev);
        my_stop(sc);
        return;
}