/*      $NetBSD: rtl81x9.c,v 1.115 2024/06/29 12:11:11 riastradh Exp $  */

/*
* Copyright (c) 1997, 1998
*      Bill Paul <[email protected]>.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*      This product includes software developed by Bill Paul.
* 4. Neither the name of the author nor the names of any co-contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*
*      FreeBSD Id: if_rl.c,v 1.17 1999/06/19 20:17:37 wpaul Exp
*/

/*
* RealTek 8129/8139 PCI NIC driver
*
* Supports several extremely cheap PCI 10/100 adapters based on
* the RealTek chipset. Datasheets can be obtained from
* www.realtek.com.tw.
*
* Written by Bill Paul <[email protected]>
* Electrical Engineering Department
* Columbia University, New York City
*/

/*
* The RealTek 8139 PCI NIC redefines the meaning of 'low end.' This is
* probably the worst PCI ethernet controller ever made, with the possible
* exception of the FEAST chip made by SMC. The 8139 supports bus-master
* DMA, but it has a terrible interface that nullifies any performance
* gains that bus-master DMA usually offers.
*
* For transmission, the chip offers a series of four TX descriptor
* registers. Each transmit frame must be in a contiguous buffer, aligned
* on a longword (32-bit) boundary. This means we almost always have to
* do mbuf copies in order to transmit a frame, except in the unlikely
* case where a) the packet fits into a single mbuf, and b) the packet
* is 32-bit aligned within the mbuf's data area. The presence of only
* four descriptor registers means that we can never have more than four
* packets queued for transmission at any one time.
*
* Reception is not much better. The driver has to allocate a single large
* buffer area (up to 64K in size) into which the chip will DMA received
* frames. Because we don't know where within this region received packets
* will begin or end, we have no choice but to copy data from the buffer
* area into mbufs in order to pass the packets up to the higher protocol
* levels.
*
* It's impossible given this rotten design to really achieve decent
* performance at 100Mbps, unless you happen to have a 400MHz PII or
* some equally overmuscled CPU to drive it.
*
* On the bright side, the 8139 does have a built-in PHY, although
* rather than using an MDIO serial interface like most other NICs, the
* PHY registers are directly accessible through the 8139's register
* space. The 8139 supports autonegotiation, as well as a 64-bit multicast
* filter.
*
* The 8129 chip is an older version of the 8139 that uses an external PHY
* chip. The 8129 has a serial MDIO interface for accessing the MII where
* the 8139 lets you directly access the on-board PHY registers. We need
* to select which interface to use depending on the chip type.
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rtl81x9.c,v 1.115 2024/06/29 12:11:11 riastradh Exp $");


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

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

#include <net/bpf.h>
#include <sys/rndsource.h>

#include <sys/bus.h>
#include <machine/endian.h>

#include <dev/mii/mii.h>
#include <dev/mii/miivar.h>

#include <dev/ic/rtl81x9reg.h>
#include <dev/ic/rtl81x9var.h>

static void rtk_reset(struct rtk_softc *);
static void rtk_rxeof(struct rtk_softc *);
static void rtk_txeof(struct rtk_softc *);
static void rtk_start(struct ifnet *);
static int rtk_ioctl(struct ifnet *, u_long, void *);
static int rtk_init(struct ifnet *);
static void rtk_stop(struct ifnet *, int);

static void rtk_watchdog(struct ifnet *);

static void rtk_eeprom_putbyte(struct rtk_softc *, int, int);
static void rtk_mii_sync(struct rtk_softc *);
static void rtk_mii_send(struct rtk_softc *, uint32_t, int);
static int rtk_mii_readreg(struct rtk_softc *, struct rtk_mii_frame *);
static int rtk_mii_writereg(struct rtk_softc *, struct rtk_mii_frame *);

static int rtk_phy_readreg(device_t, int, int, uint16_t *);
static int rtk_phy_writereg(device_t, int, int, uint16_t);
static void rtk_phy_statchg(struct ifnet *);
static void rtk_tick(void *);

static int rtk_enable(struct rtk_softc *);
static void rtk_disable(struct rtk_softc *);

static void rtk_list_tx_init(struct rtk_softc *);

#define EE_SET(x)                                       \
       CSR_WRITE_1(sc, RTK_EECMD,                      \
               CSR_READ_1(sc, RTK_EECMD) | (x))

#define EE_CLR(x)                                       \
       CSR_WRITE_1(sc, RTK_EECMD,                      \
               CSR_READ_1(sc, RTK_EECMD) & ~(x))

#define EE_DELAY()      DELAY(100)

#define ETHER_PAD_LEN (ETHER_MIN_LEN - ETHER_CRC_LEN)

/*
* Send a read command and address to the EEPROM, check for ACK.
*/
static void
rtk_eeprom_putbyte(struct rtk_softc *sc, int addr, int addr_len)
{
       int d, i;

       d = (RTK_EECMD_READ << addr_len) | addr;

       /*
        * Feed in each bit and stobe the clock.
        */
       for (i = RTK_EECMD_LEN + addr_len; i > 0; i--) {
               if (d & (1 << (i - 1))) {
                       EE_SET(RTK_EE_DATAIN);
               } else {
                       EE_CLR(RTK_EE_DATAIN);
               }
               EE_DELAY();
               EE_SET(RTK_EE_CLK);
               EE_DELAY();
               EE_CLR(RTK_EE_CLK);
               EE_DELAY();
       }
}

/*
* Read a word of data stored in the EEPROM at address 'addr.'
*/
uint16_t
rtk_read_eeprom(struct rtk_softc *sc, int addr, int addr_len)
{
       uint16_t word;
       int i;

       /* Enter EEPROM access mode. */
       CSR_WRITE_1(sc, RTK_EECMD, RTK_EEMODE_PROGRAM);
       EE_DELAY();
       EE_SET(RTK_EE_SEL);

       /*
        * Send address of word we want to read.
        */
       rtk_eeprom_putbyte(sc, addr, addr_len);

       /*
        * Start reading bits from EEPROM.
        */
       word = 0;
       for (i = 16; i > 0; i--) {
               EE_SET(RTK_EE_CLK);
               EE_DELAY();
               if (CSR_READ_1(sc, RTK_EECMD) & RTK_EE_DATAOUT)
                       word |= 1 << (i - 1);
               EE_CLR(RTK_EE_CLK);
               EE_DELAY();
       }

       /* Turn off EEPROM access mode. */
       CSR_WRITE_1(sc, RTK_EECMD, RTK_EEMODE_OFF);

       return word;
}

/*
* MII access routines are provided for the 8129, which
* doesn't have a built-in PHY. For the 8139, we fake things
* up by diverting rtk_phy_readreg()/rtk_phy_writereg() to the
* direct access PHY registers.
*/
#define MII_SET(x)                                      \
       CSR_WRITE_1(sc, RTK_MII,                        \
               CSR_READ_1(sc, RTK_MII) | (x))

#define MII_CLR(x)                                      \
       CSR_WRITE_1(sc, RTK_MII,                        \
               CSR_READ_1(sc, RTK_MII) & ~(x))

/*
* Sync the PHYs by setting data bit and strobing the clock 32 times.
*/
static void
rtk_mii_sync(struct rtk_softc *sc)
{
       int i;

       MII_SET(RTK_MII_DIR | RTK_MII_DATAOUT);

       for (i = 0; i < 32; i++) {
               MII_SET(RTK_MII_CLK);
               DELAY(1);
               MII_CLR(RTK_MII_CLK);
               DELAY(1);
       }
}

/*
* Clock a series of bits through the MII.
*/
static void
rtk_mii_send(struct rtk_softc *sc, uint32_t bits, int cnt)
{
       int i;

       MII_CLR(RTK_MII_CLK);

       for (i = cnt; i > 0; i--) {
               if (bits & (1 << (i - 1))) {
                       MII_SET(RTK_MII_DATAOUT);
               } else {
                       MII_CLR(RTK_MII_DATAOUT);
               }
               DELAY(1);
               MII_CLR(RTK_MII_CLK);
               DELAY(1);
               MII_SET(RTK_MII_CLK);
       }
}

/*
* Read an PHY register through the MII.
*/
static int
rtk_mii_readreg(struct rtk_softc *sc, struct rtk_mii_frame *frame)
{
       int i, ack, s, rv = 0;

       s = splnet();

       /*
        * Set up frame for RX.
        */
       frame->mii_stdelim = RTK_MII_STARTDELIM;
       frame->mii_opcode = RTK_MII_READOP;
       frame->mii_turnaround = 0;
       frame->mii_data = 0;

       CSR_WRITE_2(sc, RTK_MII, 0);

       /*
        * Turn on data xmit.
        */
       MII_SET(RTK_MII_DIR);

       rtk_mii_sync(sc);

       /*
        * Send command/address info.
        */
       rtk_mii_send(sc, frame->mii_stdelim, 2);
       rtk_mii_send(sc, frame->mii_opcode, 2);
       rtk_mii_send(sc, frame->mii_phyaddr, 5);
       rtk_mii_send(sc, frame->mii_regaddr, 5);

       /* Idle bit */
       MII_CLR((RTK_MII_CLK | RTK_MII_DATAOUT));
       DELAY(1);
       MII_SET(RTK_MII_CLK);
       DELAY(1);

       /* Turn off xmit. */
       MII_CLR(RTK_MII_DIR);

       /* Check for ack */
       MII_CLR(RTK_MII_CLK);
       DELAY(1);
       ack = CSR_READ_2(sc, RTK_MII) & RTK_MII_DATAIN;
       MII_SET(RTK_MII_CLK);
       DELAY(1);

       /*
        * Now try reading data bits. If the ack failed, we still
        * need to clock through 16 cycles to keep the PHY(s) in sync.
        */
       if (ack) {
               for (i = 0; i < 16; i++) {
                       MII_CLR(RTK_MII_CLK);
                       DELAY(1);
                       MII_SET(RTK_MII_CLK);
                       DELAY(1);
               }
               rv = -1;
               goto fail;
       }

       for (i = 16; i > 0; i--) {
               MII_CLR(RTK_MII_CLK);
               DELAY(1);
               if (!ack) {
                       if (CSR_READ_2(sc, RTK_MII) & RTK_MII_DATAIN)
                               frame->mii_data |= 1 << (i - 1);
                       DELAY(1);
               }
               MII_SET(RTK_MII_CLK);
               DELAY(1);
       }

fail:
       MII_CLR(RTK_MII_CLK);
       DELAY(1);
       MII_SET(RTK_MII_CLK);
       DELAY(1);

       splx(s);

       return rv;
}

/*
* Write to a PHY register through the MII.
*/
static int
rtk_mii_writereg(struct rtk_softc *sc, struct rtk_mii_frame *frame)
{
       int s;

       s = splnet();
       /*
        * Set up frame for TX.
        */
       frame->mii_stdelim = RTK_MII_STARTDELIM;
       frame->mii_opcode = RTK_MII_WRITEOP;
       frame->mii_turnaround = RTK_MII_TURNAROUND;

       /*
        * Turn on data output.
        */
       MII_SET(RTK_MII_DIR);

       rtk_mii_sync(sc);

       rtk_mii_send(sc, frame->mii_stdelim, 2);
       rtk_mii_send(sc, frame->mii_opcode, 2);
       rtk_mii_send(sc, frame->mii_phyaddr, 5);
       rtk_mii_send(sc, frame->mii_regaddr, 5);
       rtk_mii_send(sc, frame->mii_turnaround, 2);
       rtk_mii_send(sc, frame->mii_data, 16);

       /* Idle bit. */
       MII_SET(RTK_MII_CLK);
       DELAY(1);
       MII_CLR(RTK_MII_CLK);
       DELAY(1);

       /*
        * Turn off xmit.
        */
       MII_CLR(RTK_MII_DIR);

       splx(s);

       return 0;
}

static int
rtk_phy_readreg(device_t self, int phy, int reg, uint16_t *val)
{
       struct rtk_softc *sc = device_private(self);
       struct rtk_mii_frame frame;
       int rv;
       int rtk8139_reg;

       if ((sc->sc_quirk & RTKQ_8129) == 0) {
               if (phy != 7)
                       return -1;

               switch (reg) {
               case MII_BMCR:
                       rtk8139_reg = RTK_BMCR;
                       break;
               case MII_BMSR:
                       rtk8139_reg = RTK_BMSR;
                       break;
               case MII_ANAR:
                       rtk8139_reg = RTK_ANAR;
                       break;
               case MII_ANER:
                       rtk8139_reg = RTK_ANER;
                       break;
               case MII_ANLPAR:
                       rtk8139_reg = RTK_LPAR;
                       break;
               case MII_PHYIDR1:
               case MII_PHYIDR2:
                       *val = 0;
                       return 0;
               default:
#if 0
                       printf("%s: bad phy register\n", device_xname(self));
#endif
                       return -1;
               }
               *val = CSR_READ_2(sc, rtk8139_reg);
               return 0;
       }

       memset(&frame, 0, sizeof(frame));

       frame.mii_phyaddr = phy;
       frame.mii_regaddr = reg;
       rv = rtk_mii_readreg(sc, &frame);
       *val = frame.mii_data;

       return rv;
}

static int
rtk_phy_writereg(device_t self, int phy, int reg, uint16_t val)
{
       struct rtk_softc *sc = device_private(self);
       struct rtk_mii_frame frame;
       int rtk8139_reg;

       if ((sc->sc_quirk & RTKQ_8129) == 0) {
               if (phy != 7)
                       return -1;

               switch (reg) {
               case MII_BMCR:
                       rtk8139_reg = RTK_BMCR;
                       break;
               case MII_BMSR:
                       rtk8139_reg = RTK_BMSR;
                       break;
               case MII_ANAR:
                       rtk8139_reg = RTK_ANAR;
                       break;
               case MII_ANER:
                       rtk8139_reg = RTK_ANER;
                       break;
               case MII_ANLPAR:
                       rtk8139_reg = RTK_LPAR;
                       break;
               default:
#if 0
                       printf("%s: bad phy register\n", device_xname(self));
#endif
                       return -1;
               }
               CSR_WRITE_2(sc, rtk8139_reg, val);
               return 0;
       }

       memset(&frame, 0, sizeof(frame));

       frame.mii_phyaddr = phy;
       frame.mii_regaddr = reg;
       frame.mii_data = val;

       return rtk_mii_writereg(sc, &frame);
}

static void
rtk_phy_statchg(struct ifnet *ifp)
{

       /* Nothing to do. */
}

#define rtk_calchash(addr) \
       (ether_crc32_be((addr), ETHER_ADDR_LEN) >> 26)

/*
* Program the 64-bit multicast hash filter.
*/
void
rtk_setmulti(struct rtk_softc *sc)
{
       struct ethercom *ec = &sc->ethercom;
       struct ifnet *ifp = &ec->ec_if;
       uint32_t hashes[2] = { 0, 0 };
       uint32_t rxfilt;
       struct ether_multi *enm;
       struct ether_multistep step;
       int h, mcnt;

       rxfilt = CSR_READ_4(sc, RTK_RXCFG);

       if (ifp->if_flags & IFF_PROMISC) {
allmulti:
               ifp->if_flags |= IFF_ALLMULTI;
               rxfilt |= RTK_RXCFG_RX_MULTI;
               CSR_WRITE_4(sc, RTK_RXCFG, rxfilt);
               CSR_WRITE_4(sc, RTK_MAR0, 0xFFFFFFFF);
               CSR_WRITE_4(sc, RTK_MAR4, 0xFFFFFFFF);
               return;
       }

       /* first, zot all the existing hash bits */
       CSR_WRITE_4(sc, RTK_MAR0, 0);
       CSR_WRITE_4(sc, RTK_MAR4, 0);

       /* now program new ones */
       ETHER_LOCK(ec);
       ETHER_FIRST_MULTI(step, ec, enm);
       mcnt = 0;
       while (enm != NULL) {
               if (memcmp(enm->enm_addrlo, enm->enm_addrhi,
                   ETHER_ADDR_LEN) != 0) {
                       ETHER_UNLOCK(ec);
                       goto allmulti;
               }

               h = rtk_calchash(enm->enm_addrlo);
               if (h < 32)
                       hashes[0] |= __BIT(h);
               else
                       hashes[1] |= __BIT(h - 32);
               mcnt++;
               ETHER_NEXT_MULTI(step, enm);
       }
       ETHER_UNLOCK(ec);

       ifp->if_flags &= ~IFF_ALLMULTI;

       if (mcnt)
               rxfilt |= RTK_RXCFG_RX_MULTI;
       else
               rxfilt &= ~RTK_RXCFG_RX_MULTI;

       CSR_WRITE_4(sc, RTK_RXCFG, rxfilt);

       /*
        * For some unfathomable reason, RealTek decided to reverse
        * the order of the multicast hash registers in the PCI Express
        * parts. This means we have to write the hash pattern in reverse
        * order for those devices.
        */
       if ((sc->sc_quirk & RTKQ_PCIE) != 0) {
               CSR_WRITE_4(sc, RTK_MAR0, bswap32(hashes[1]));
               CSR_WRITE_4(sc, RTK_MAR4, bswap32(hashes[0]));
       } else {
               CSR_WRITE_4(sc, RTK_MAR0, hashes[0]);
               CSR_WRITE_4(sc, RTK_MAR4, hashes[1]);
       }
}

void
rtk_reset(struct rtk_softc *sc)
{
       int i;

       CSR_WRITE_1(sc, RTK_COMMAND, RTK_CMD_RESET);

       for (i = 0; i < RTK_TIMEOUT; i++) {
               DELAY(10);
               if ((CSR_READ_1(sc, RTK_COMMAND) & RTK_CMD_RESET) == 0)
                       break;
       }
       if (i == RTK_TIMEOUT)
               printf("%s: reset never completed!\n",
                   device_xname(sc->sc_dev));
}

/*
* Attach the interface. Allocate softc structures, do ifmedia
* setup and ethernet/BPF attach.
*/
void
rtk_attach(struct rtk_softc *sc)
{
       device_t self = sc->sc_dev;
       struct ifnet *ifp;
       struct mii_data * const mii = &sc->mii;
       struct rtk_tx_desc *txd;
       uint16_t val;
       uint8_t eaddr[ETHER_ADDR_LEN];
       int error;
       int i, addr_len;

       callout_init(&sc->rtk_tick_ch, 0);
       callout_setfunc(&sc->rtk_tick_ch, rtk_tick, sc);

       /*
        * Check EEPROM type 9346 or 9356.
        */
       if (rtk_read_eeprom(sc, RTK_EE_ID, RTK_EEADDR_LEN1) == 0x8129)
               addr_len = RTK_EEADDR_LEN1;
       else
               addr_len = RTK_EEADDR_LEN0;

       /*
        * Get station address.
        */
       val = rtk_read_eeprom(sc, RTK_EE_EADDR0, addr_len);
       eaddr[0] = val & 0xff;
       eaddr[1] = val >> 8;
       val = rtk_read_eeprom(sc, RTK_EE_EADDR1, addr_len);
       eaddr[2] = val & 0xff;
       eaddr[3] = val >> 8;
       val = rtk_read_eeprom(sc, RTK_EE_EADDR2, addr_len);
       eaddr[4] = val & 0xff;
       eaddr[5] = val >> 8;

       if ((error = bus_dmamem_alloc(sc->sc_dmat,
           RTK_RXBUFLEN + 16, PAGE_SIZE, 0, &sc->sc_dmaseg, 1, &sc->sc_dmanseg,
           BUS_DMA_NOWAIT)) != 0) {
               aprint_error_dev(self,
                   "can't allocate recv buffer, error = %d\n", error);
               goto fail_0;
       }

       if ((error = bus_dmamem_map(sc->sc_dmat, &sc->sc_dmaseg, sc->sc_dmanseg,
           RTK_RXBUFLEN + 16, (void **)&sc->rtk_rx_buf,
           BUS_DMA_NOWAIT | BUS_DMA_COHERENT)) != 0) {
               aprint_error_dev(self,
                   "can't map recv buffer, error = %d\n", error);
               goto fail_1;
       }

       if ((error = bus_dmamap_create(sc->sc_dmat,
           RTK_RXBUFLEN + 16, 1, RTK_RXBUFLEN + 16, 0, BUS_DMA_NOWAIT,
           &sc->recv_dmamap)) != 0) {
               aprint_error_dev(self,
                   "can't create recv buffer DMA map, error = %d\n", error);
               goto fail_2;
       }

       if ((error = bus_dmamap_load(sc->sc_dmat, sc->recv_dmamap,
           sc->rtk_rx_buf, RTK_RXBUFLEN + 16,
           NULL, BUS_DMA_READ | BUS_DMA_NOWAIT)) != 0) {
               aprint_error_dev(self,
                   "can't load recv buffer DMA map, error = %d\n", error);
               goto fail_3;
       }

       for (i = 0; i < RTK_TX_LIST_CNT; i++) {
               txd = &sc->rtk_tx_descs[i];
               if ((error = bus_dmamap_create(sc->sc_dmat,
                   MCLBYTES, 1, MCLBYTES, 0, BUS_DMA_NOWAIT,
                   &txd->txd_dmamap)) != 0) {
                       aprint_error_dev(self,
                           "can't create snd buffer DMA map, error = %d\n",
                           error);
                       goto fail_4;
               }
               txd->txd_txaddr = RTK_TXADDR0 + (i * 4);
               txd->txd_txstat = RTK_TXSTAT0 + (i * 4);
       }
       SIMPLEQ_INIT(&sc->rtk_tx_free);
       SIMPLEQ_INIT(&sc->rtk_tx_dirty);

       /*
        * From this point forward, the attachment cannot fail. A failure
        * before this releases all resources that may have been
        * allocated.
        */
       sc->sc_flags |= RTK_ATTACHED;

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

       aprint_normal_dev(self, "Ethernet address %s\n", ether_sprintf(eaddr));

       ifp = &sc->ethercom.ec_if;
       ifp->if_softc = sc;
       strcpy(ifp->if_xname, device_xname(self));
       ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
       ifp->if_ioctl = rtk_ioctl;
       ifp->if_start = rtk_start;
       ifp->if_watchdog = rtk_watchdog;
       ifp->if_init = rtk_init;
       ifp->if_stop = rtk_stop;
       IFQ_SET_READY(&ifp->if_snd);

       /*
        * Do ifmedia setup.
        */
       mii->mii_ifp = ifp;
       mii->mii_readreg = rtk_phy_readreg;
       mii->mii_writereg = rtk_phy_writereg;
       mii->mii_statchg = rtk_phy_statchg;
       sc->ethercom.ec_mii = mii;
       ifmedia_init(&mii->mii_media, IFM_IMASK, ether_mediachange,
           ether_mediastatus);
       mii_attach(self, mii, 0xffffffff, MII_PHY_ANY, MII_OFFSET_ANY, 0);

       /* Choose a default media. */
       if (LIST_FIRST(&mii->mii_phys) == NULL) {
               ifmedia_add(&mii->mii_media, IFM_ETHER | IFM_NONE, 0, NULL);
               ifmedia_set(&mii->mii_media, IFM_ETHER | IFM_NONE);
       } else
               ifmedia_set(&mii->mii_media, IFM_ETHER | IFM_AUTO);

       /*
        * Call MI attach routines.
        */
       if_attach(ifp);
       if_deferred_start_init(ifp, NULL);
       ether_ifattach(ifp, eaddr);

       rnd_attach_source(&sc->rnd_source, device_xname(self),
           RND_TYPE_NET, RND_FLAG_DEFAULT);

       return;
fail_4:
       for (i = 0; i < RTK_TX_LIST_CNT; i++) {
               txd = &sc->rtk_tx_descs[i];
               if (txd->txd_dmamap != NULL)
                       bus_dmamap_destroy(sc->sc_dmat, txd->txd_dmamap);
       }
fail_3:
       bus_dmamap_destroy(sc->sc_dmat, sc->recv_dmamap);
fail_2:
       bus_dmamem_unmap(sc->sc_dmat, sc->rtk_rx_buf,
           RTK_RXBUFLEN + 16);
fail_1:
       bus_dmamem_free(sc->sc_dmat, &sc->sc_dmaseg, sc->sc_dmanseg);
fail_0:
       return;
}

/*
* Initialize the transmit descriptors.
*/
static void
rtk_list_tx_init(struct rtk_softc *sc)
{
       struct rtk_tx_desc *txd;
       int i;

       while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_dirty)) != NULL)
               SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_dirty, txd_q);
       while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_free)) != NULL)
               SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_free, txd_q);

       for (i = 0; i < RTK_TX_LIST_CNT; i++) {
               txd = &sc->rtk_tx_descs[i];
               CSR_WRITE_4(sc, txd->txd_txaddr, 0);
               SIMPLEQ_INSERT_TAIL(&sc->rtk_tx_free, txd, txd_q);
       }
}

/*
* rtk_activate:
*     Handle device activation/deactivation requests.
*/
int
rtk_activate(device_t self, enum devact act)
{
       struct rtk_softc *sc = device_private(self);

       switch (act) {
       case DVACT_DEACTIVATE:
               if_deactivate(&sc->ethercom.ec_if);
               return 0;
       default:
               return EOPNOTSUPP;
       }
}

/*
* rtk_detach:
*     Detach a rtk interface.
*/
int
rtk_detach(struct rtk_softc *sc)
{
       struct ifnet *ifp = &sc->ethercom.ec_if;
       struct rtk_tx_desc *txd;
       int i;

       /*
        * Succeed now if there isn't any work to do.
        */
       if ((sc->sc_flags & RTK_ATTACHED) == 0)
               return 0;

       /* Unhook our tick handler. */
       callout_stop(&sc->rtk_tick_ch);

       /* Detach all PHYs. */
       mii_detach(&sc->mii, MII_PHY_ANY, MII_OFFSET_ANY);

       rnd_detach_source(&sc->rnd_source);

       ether_ifdetach(ifp);
       if_detach(ifp);

       /* Delete all remaining media. */
       ifmedia_fini(&sc->mii.mii_media);

       for (i = 0; i < RTK_TX_LIST_CNT; i++) {
               txd = &sc->rtk_tx_descs[i];
               if (txd->txd_dmamap != NULL)
                       bus_dmamap_destroy(sc->sc_dmat, txd->txd_dmamap);
       }
       bus_dmamap_destroy(sc->sc_dmat, sc->recv_dmamap);
       bus_dmamem_unmap(sc->sc_dmat, sc->rtk_rx_buf,
           RTK_RXBUFLEN + 16);
       bus_dmamem_free(sc->sc_dmat, &sc->sc_dmaseg, sc->sc_dmanseg);

       /* we don't want to run again */
       sc->sc_flags &= ~RTK_ATTACHED;

       return 0;
}

/*
* rtk_enable:
*     Enable the RTL81X9 chip.
*/
int
rtk_enable(struct rtk_softc *sc)
{

       if (RTK_IS_ENABLED(sc) == 0 && sc->sc_enable != NULL) {
               if ((*sc->sc_enable)(sc) != 0) {
                       printf("%s: device enable failed\n",
                           device_xname(sc->sc_dev));
                       return EIO;
               }
               sc->sc_flags |= RTK_ENABLED;
       }
       return 0;
}

/*
* rtk_disable:
*     Disable the RTL81X9 chip.
*/
void
rtk_disable(struct rtk_softc *sc)
{

       if (RTK_IS_ENABLED(sc) && sc->sc_disable != NULL) {
               (*sc->sc_disable)(sc);
               sc->sc_flags &= ~RTK_ENABLED;
       }
}

/*
* A frame has been uploaded: pass the resulting mbuf chain up to
* the higher level protocols.
*
* You know there's something wrong with a PCI bus-master chip design.
*
* The receive operation is badly documented in the datasheet, so I'll
* attempt to document it here. The driver provides a buffer area and
* places its base address in the RX buffer start address register.
* The chip then begins copying frames into the RX buffer. Each frame
* is preceded by a 32-bit RX status word which specifies the length
* of the frame and certain other status bits. Each frame (starting with
* the status word) is also 32-bit aligned. The frame length is in the
* first 16 bits of the status word; the lower 15 bits correspond with
* the 'rx status register' mentioned in the datasheet.
*
* Note: to make the Alpha happy, the frame payload needs to be aligned
* on a 32-bit boundary. To achieve this, we copy the data to mbuf
* shifted forward 2 bytes.
*/
static void
rtk_rxeof(struct rtk_softc *sc)
{
       struct mbuf *m;
       struct ifnet *ifp;
       uint8_t *rxbufpos, *dst;
       u_int total_len, wrap;
       uint32_t rxstat;
       uint16_t cur_rx, new_rx;
       uint16_t limit;
       uint16_t rx_bytes, max_bytes;

       ifp = &sc->ethercom.ec_if;

       cur_rx = (CSR_READ_2(sc, RTK_CURRXADDR) + 16) % RTK_RXBUFLEN;

       /* Do not try to read past this point. */
       limit = CSR_READ_2(sc, RTK_CURRXBUF) % RTK_RXBUFLEN;

       if (limit < cur_rx)
               max_bytes = (RTK_RXBUFLEN - cur_rx) + limit;
       else
               max_bytes = limit - cur_rx;
       rx_bytes = 0;

       while ((CSR_READ_1(sc, RTK_COMMAND) & RTK_CMD_EMPTY_RXBUF) == 0) {
               rxbufpos = sc->rtk_rx_buf + cur_rx;
               bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap, cur_rx,
                   RTK_RXSTAT_LEN, BUS_DMASYNC_POSTREAD);
               rxstat = le32toh(*(uint32_t *)rxbufpos);
               bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap, cur_rx,
                   RTK_RXSTAT_LEN, BUS_DMASYNC_PREREAD);

               /*
                * Here's a totally undocumented fact for you. When the
                * RealTek chip is in the process of copying a packet into
                * RAM for you, the length will be 0xfff0. If you spot a
                * packet header with this value, you need to stop. The
                * datasheet makes absolutely no mention of this and
                * RealTek should be shot for this.
                */
               total_len = rxstat >> 16;
               if (total_len == RTK_RXSTAT_UNFINISHED)
                       break;

               if ((rxstat & RTK_RXSTAT_RXOK) == 0 ||
                   total_len < ETHER_MIN_LEN ||
                   total_len > (MCLBYTES - RTK_ETHER_ALIGN)) {
                       if_statinc(ifp, if_ierrors);

                       /*
                        * submitted by:[netbsd-pcmcia:00484]
                        *      Takahiro Kambe <[email protected]>
                        * obtain from:
                        *     FreeBSD if_rl.c rev 1.24->1.25
                        *
                        */
#if 0
                       if (rxstat & (RTK_RXSTAT_BADSYM | RTK_RXSTAT_RUNT |
                           RTK_RXSTAT_GIANT | RTK_RXSTAT_CRCERR |
                           RTK_RXSTAT_ALIGNERR)) {
                               CSR_WRITE_2(sc, RTK_COMMAND, RTK_CMD_TX_ENB);
                               CSR_WRITE_2(sc, RTK_COMMAND,
                                   RTK_CMD_TX_ENB | RTK_CMD_RX_ENB);
                               CSR_WRITE_4(sc, RTK_RXCFG, RTK_RXCFG_CONFIG);
                               CSR_WRITE_4(sc, RTK_RXADDR,
                                   sc->recv_dmamap->dm_segs[0].ds_addr);
                               cur_rx = 0;
                       }
                       break;
#else
                       rtk_init(ifp);
                       return;
#endif
               }

               /* No errors; receive the packet. */
               rx_bytes += total_len + RTK_RXSTAT_LEN;

               /*
                * Avoid trying to read more bytes than we know
                * the chip has prepared for us.
                */
               if (rx_bytes > max_bytes)
                       break;

               /*
                * Skip the status word, wrapping around to the beginning
                * of the Rx area, if necessary.
                */
               cur_rx = (cur_rx + RTK_RXSTAT_LEN) % RTK_RXBUFLEN;
               rxbufpos = sc->rtk_rx_buf + cur_rx;

               /*
                * Compute the number of bytes at which the packet
                * will wrap to the beginning of the ring buffer.
                */
               wrap = RTK_RXBUFLEN - cur_rx;

               /*
                * Compute where the next pending packet is.
                */
               if (total_len > wrap)
                       new_rx = total_len - wrap;
               else
                       new_rx = cur_rx + total_len;
               /* Round up to 32-bit boundary. */
               new_rx = roundup2(new_rx, sizeof(uint32_t)) % RTK_RXBUFLEN;

               /*
                * The RealTek chip includes the CRC with every
                * incoming packet; trim it off here.
                */
               total_len -= ETHER_CRC_LEN;

               /*
                * Now allocate an mbuf (and possibly a cluster) to hold
                * the packet. Note we offset the packet 2 bytes so that
                * data after the Ethernet header will be 4-byte aligned.
                */
               MGETHDR(m, M_DONTWAIT, MT_DATA);
               if (m == NULL) {
                       printf("%s: unable to allocate Rx mbuf\n",
                           device_xname(sc->sc_dev));
                       if_statinc(ifp, if_ierrors);
                       goto next_packet;
               }
               MCLAIM(m, &sc->ethercom.ec_rx_mowner);
               if (total_len > (MHLEN - RTK_ETHER_ALIGN)) {
                       MCLGET(m, M_DONTWAIT);
                       if ((m->m_flags & M_EXT) == 0) {
                               printf("%s: unable to allocate Rx cluster\n",
                                   device_xname(sc->sc_dev));
                               if_statinc(ifp, if_ierrors);
                               m_freem(m);
                               m = NULL;
                               goto next_packet;
                       }
               }
               m->m_data += RTK_ETHER_ALIGN;   /* for alignment */
               m_set_rcvif(m, ifp);
               m->m_pkthdr.len = m->m_len = total_len;
               dst = mtod(m, void *);

               /*
                * If the packet wraps, copy up to the wrapping point.
                */
               if (total_len > wrap) {
                       bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
                           cur_rx, wrap, BUS_DMASYNC_POSTREAD);
                       memcpy(dst, rxbufpos, wrap);
                       bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
                           cur_rx, wrap, BUS_DMASYNC_PREREAD);
                       cur_rx = 0;
                       rxbufpos = sc->rtk_rx_buf;
                       total_len -= wrap;
                       dst += wrap;
               }

               /*
                * ...and now the rest.
                */
               bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
                   cur_rx, total_len, BUS_DMASYNC_POSTREAD);
               memcpy(dst, rxbufpos, total_len);
               bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
                   cur_rx, total_len, BUS_DMASYNC_PREREAD);

next_packet:
               CSR_WRITE_2(sc, RTK_CURRXADDR, (new_rx - 16) % RTK_RXBUFLEN);
               cur_rx = new_rx;

               if (m == NULL)
                       continue;

               /* pass it on. */
               if_percpuq_enqueue(ifp->if_percpuq, m);
       }
}

/*
* A frame was downloaded to the chip. It's safe for us to clean up
* the list buffers.
*/
static void
rtk_txeof(struct rtk_softc *sc)
{
       struct ifnet *ifp;
       struct rtk_tx_desc *txd;
       uint32_t txstat;

       ifp = &sc->ethercom.ec_if;

       /*
        * Go through our tx list and free mbufs for those
        * frames that have been uploaded.
        */
       while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_dirty)) != NULL) {
               txstat = CSR_READ_4(sc, txd->txd_txstat);
               if ((txstat & (RTK_TXSTAT_TX_OK |
                   RTK_TXSTAT_TX_UNDERRUN | RTK_TXSTAT_TXABRT)) == 0)
                       break;

               SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_dirty, txd_q);

               bus_dmamap_sync(sc->sc_dmat, txd->txd_dmamap, 0,
                   txd->txd_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
               bus_dmamap_unload(sc->sc_dmat, txd->txd_dmamap);
               m_freem(txd->txd_mbuf);
               txd->txd_mbuf = NULL;

               net_stat_ref_t nsr = IF_STAT_GETREF(ifp);
               if_statadd_ref(ifp, nsr, if_collisions,
                   (txstat & RTK_TXSTAT_COLLCNT) >> 24);

               if (txstat & RTK_TXSTAT_TX_OK)
                       if_statinc_ref(ifp, nsr, if_opackets);
               else {
                       if_statinc_ref(ifp, nsr, if_oerrors);

                       /*
                        * Increase Early TX threshold if underrun occurred.
                        * Increase step 64 bytes.
                        */
                       if (txstat & RTK_TXSTAT_TX_UNDERRUN) {
#ifdef DEBUG
                               printf("%s: transmit underrun;",
                                   device_xname(sc->sc_dev));
#endif
                               if (sc->sc_txthresh < RTK_TXTH_MAX) {
                                       sc->sc_txthresh += 2;
#ifdef DEBUG
                                       printf(" new threshold: %d bytes",
                                           sc->sc_txthresh * 32);
#endif
                               }
#ifdef DEBUG
                               printf("\n");
#endif
                       }
                       if (txstat & (RTK_TXSTAT_TXABRT | RTK_TXSTAT_OUTOFWIN))
                               CSR_WRITE_4(sc, RTK_TXCFG, RTK_TXCFG_CONFIG);
               }
               IF_STAT_PUTREF(ifp);
               SIMPLEQ_INSERT_TAIL(&sc->rtk_tx_free, txd, txd_q);
               ifp->if_flags &= ~IFF_OACTIVE;
       }

       /* Clear the timeout timer if there is no pending packet. */
       if (SIMPLEQ_EMPTY(&sc->rtk_tx_dirty))
               ifp->if_timer = 0;

}

int
rtk_intr(void *arg)
{
       struct rtk_softc *sc;
       struct ifnet *ifp;
       uint16_t status, rndstatus = 0;
       int handled;

       sc = arg;
       ifp = &sc->ethercom.ec_if;

       if (!device_has_power(sc->sc_dev))
               return 0;

       /* Disable interrupts. */
       CSR_WRITE_2(sc, RTK_IMR, 0x0000);

       handled = 0;
       for (;;) {

               status = CSR_READ_2(sc, RTK_ISR);

               if (status == 0xffff)
                       break; /* Card is gone... */

               if (status) {
                       CSR_WRITE_2(sc, RTK_ISR, status);
                       rndstatus = status;
               }

               if ((status & RTK_INTRS) == 0)
                       break;

               handled = 1;

               if (status & RTK_ISR_RX_OK)
                       rtk_rxeof(sc);

               if (status & RTK_ISR_RX_ERR)
                       rtk_rxeof(sc);

               if (status & (RTK_ISR_TX_OK | RTK_ISR_TX_ERR))
                       rtk_txeof(sc);

               if (status & RTK_ISR_SYSTEM_ERR) {
                       rtk_reset(sc);
                       rtk_init(ifp);
               }
       }

       /* Re-enable interrupts. */
       CSR_WRITE_2(sc, RTK_IMR, RTK_INTRS);

       if_schedule_deferred_start(ifp);

       rnd_add_uint32(&sc->rnd_source, rndstatus);

       return handled;
}

/*
* Main transmit routine.
*/

static void
rtk_start(struct ifnet *ifp)
{
       struct rtk_softc *sc;
       struct rtk_tx_desc *txd;
       struct mbuf *m_head, *m_new;
       int error, len;

       sc = ifp->if_softc;

       while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_free)) != NULL) {
               IFQ_POLL(&ifp->if_snd, m_head);
               if (m_head == NULL)
                       break;
               m_new = NULL;

               /*
                * Load the DMA map.  If this fails, the packet didn't
                * fit in one DMA segment, and we need to copy.  Note,
                * the packet must also be aligned.
                * if the packet is too small, copy it too, so we're sure
                * so have enough room for the pad buffer.
                */
               if ((mtod(m_head, uintptr_t) & 3) != 0 ||
                   m_head->m_pkthdr.len < ETHER_PAD_LEN ||
                   bus_dmamap_load_mbuf(sc->sc_dmat, txd->txd_dmamap,
                       m_head, BUS_DMA_WRITE | BUS_DMA_NOWAIT) != 0) {
                       MGETHDR(m_new, M_DONTWAIT, MT_DATA);
                       if (m_new == NULL) {
                               printf("%s: unable to allocate Tx mbuf\n",
                                   device_xname(sc->sc_dev));
                               break;
                       }
                       MCLAIM(m_new, &sc->ethercom.ec_rx_mowner);
                       if (m_head->m_pkthdr.len > MHLEN) {
                               MCLGET(m_new, M_DONTWAIT);
                               if ((m_new->m_flags & M_EXT) == 0) {
                                       printf("%s: unable to allocate Tx "
                                           "cluster\n",
                                           device_xname(sc->sc_dev));
                                       m_freem(m_new);
                                       break;
                               }
                       }
                       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;
                       if (m_head->m_pkthdr.len < ETHER_PAD_LEN) {
                               memset(
                                   mtod(m_new, char *) + m_head->m_pkthdr.len,
                                   0, ETHER_PAD_LEN - m_head->m_pkthdr.len);
                               m_new->m_pkthdr.len = m_new->m_len =
                                   ETHER_PAD_LEN;
                       }
                       error = bus_dmamap_load_mbuf(sc->sc_dmat,
                           txd->txd_dmamap, m_new,
                           BUS_DMA_WRITE | BUS_DMA_NOWAIT);
                       if (error) {
                               printf("%s: unable to load Tx buffer, "
                                   "error = %d\n",
                                   device_xname(sc->sc_dev), error);
                               break;
                       }
               }
               IFQ_DEQUEUE(&ifp->if_snd, m_head);
               /*
                * If there's a BPF listener, bounce a copy of this frame
                * to him.
                */
               bpf_mtap(ifp, m_head, BPF_D_OUT);
               if (m_new != NULL) {
                       m_freem(m_head);
                       m_head = m_new;
               }
               txd->txd_mbuf = m_head;

               SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_free, txd_q);
               SIMPLEQ_INSERT_TAIL(&sc->rtk_tx_dirty, txd, txd_q);

               /*
                * Transmit the frame.
                */
               bus_dmamap_sync(sc->sc_dmat,
                   txd->txd_dmamap, 0, txd->txd_dmamap->dm_mapsize,
                   BUS_DMASYNC_PREWRITE);

               len = txd->txd_dmamap->dm_segs[0].ds_len;

               CSR_WRITE_4(sc, txd->txd_txaddr,
                   txd->txd_dmamap->dm_segs[0].ds_addr);
               CSR_WRITE_4(sc, txd->txd_txstat,
                   RTK_TXSTAT_THRESH(sc->sc_txthresh) | len);

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

       /*
        * We broke out of the loop because all our TX slots are
        * full. Mark the NIC as busy until it drains some of the
        * packets from the queue.
        */
       if (SIMPLEQ_EMPTY(&sc->rtk_tx_free))
               ifp->if_flags |= IFF_OACTIVE;
}

static int
rtk_init(struct ifnet *ifp)
{
       struct rtk_softc *sc = ifp->if_softc;
       int error, i;
       uint32_t rxcfg;

       if ((error = rtk_enable(sc)) != 0)
               goto out;

       /*
        * Cancel pending I/O.
        */
       rtk_stop(ifp, 0);

       /* Init our MAC address */
       for (i = 0; i < ETHER_ADDR_LEN; i++) {
               CSR_WRITE_1(sc, RTK_IDR0 + i, CLLADDR(ifp->if_sadl)[i]);
       }

       /* Init the RX buffer pointer register. */
       bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap, 0,
           sc->recv_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
       CSR_WRITE_4(sc, RTK_RXADDR, sc->recv_dmamap->dm_segs[0].ds_addr);

       /* Init TX descriptors. */
       rtk_list_tx_init(sc);

       /* Init Early TX threshold. */
       sc->sc_txthresh = RTK_TXTH_256;
       /*
        * Enable transmit and receive.
        */
       CSR_WRITE_1(sc, RTK_COMMAND, RTK_CMD_TX_ENB | RTK_CMD_RX_ENB);

       /*
        * Set the initial TX and RX configuration.
        */
       CSR_WRITE_4(sc, RTK_TXCFG, RTK_TXCFG_CONFIG);
       CSR_WRITE_4(sc, RTK_RXCFG, RTK_RXCFG_CONFIG);

       /* Set the individual bit to receive frames for this host only. */
       rxcfg = CSR_READ_4(sc, RTK_RXCFG);
       rxcfg |= RTK_RXCFG_RX_INDIV;

       /* If we want promiscuous mode, set the allframes bit. */
       if (ifp->if_flags & IFF_PROMISC) {
               rxcfg |= RTK_RXCFG_RX_ALLPHYS;
               CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
       } else {
               rxcfg &= ~RTK_RXCFG_RX_ALLPHYS;
               CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
       }

       /*
        * Set capture broadcast bit to capture broadcast frames.
        */
       if (ifp->if_flags & IFF_BROADCAST) {
               rxcfg |= RTK_RXCFG_RX_BROAD;
               CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
       } else {
               rxcfg &= ~RTK_RXCFG_RX_BROAD;
               CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
       }

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

       /*
        * Enable interrupts.
        */
       CSR_WRITE_2(sc, RTK_IMR, RTK_INTRS);

       /* Start RX/TX process. */
       CSR_WRITE_4(sc, RTK_MISSEDPKT, 0);

       /* Enable receiver and transmitter. */
       CSR_WRITE_1(sc, RTK_COMMAND, RTK_CMD_TX_ENB | RTK_CMD_RX_ENB);

       CSR_WRITE_1(sc, RTK_CFG1, RTK_CFG1_DRVLOAD | RTK_CFG1_FULLDUPLEX);

       /*
        * Set current media.
        */
       if ((error = ether_mediachange(ifp)) != 0)
               goto out;

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

       callout_schedule(&sc->rtk_tick_ch, hz);

out:
       if (error) {
               ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
               ifp->if_timer = 0;
               printf("%s: interface not running\n", device_xname(sc->sc_dev));
       }
       return error;
}

static int
rtk_ioctl(struct ifnet *ifp, u_long command, void *data)
{
       struct rtk_softc *sc = ifp->if_softc;
       int s, error;

       s = splnet();
       error = ether_ioctl(ifp, command, data);
       if (error == ENETRESET) {
               if (ifp->if_flags & IFF_RUNNING) {
                       /*
                        * Multicast list has changed.  Set the
                        * hardware filter accordingly.
                        */
                       rtk_setmulti(sc);
               }
               error = 0;
       }
       splx(s);

       return error;
}

static void
rtk_watchdog(struct ifnet *ifp)
{
       struct rtk_softc *sc;

       sc = ifp->if_softc;

       printf("%s: watchdog timeout\n", device_xname(sc->sc_dev));
       if_statinc(ifp, if_oerrors);
       rtk_txeof(sc);
       rtk_rxeof(sc);
       rtk_init(ifp);
}

/*
* Stop the adapter and free any mbufs allocated to the
* RX and TX lists.
*/
static void
rtk_stop(struct ifnet *ifp, int disable)
{
       struct rtk_softc *sc = ifp->if_softc;
       struct rtk_tx_desc *txd;

       callout_stop(&sc->rtk_tick_ch);

       mii_down(&sc->mii);

       CSR_WRITE_1(sc, RTK_COMMAND, 0x00);
       CSR_WRITE_2(sc, RTK_IMR, 0x0000);

       /*
        * Free the TX list buffers.
        */
       while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_dirty)) != NULL) {
               SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_dirty, txd_q);
               bus_dmamap_unload(sc->sc_dmat, txd->txd_dmamap);
               m_freem(txd->txd_mbuf);
               txd->txd_mbuf = NULL;
               CSR_WRITE_4(sc, txd->txd_txaddr, 0);
       }

       if (disable)
               rtk_disable(sc);

       ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
       ifp->if_timer = 0;
}

static void
rtk_tick(void *arg)
{
       struct rtk_softc *sc = arg;
       int s;

       s = splnet();
       mii_tick(&sc->mii);
       splx(s);

       callout_schedule(&sc->rtk_tick_ch, hz);
}