root/sys/dev/netif/rl/if_rl.c
/*
 * Copyright (c) 1997, 1998
 *      Bill Paul <wpaul@ctr.columbia.edu>.  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: src/sys/pci/if_rl.c,v 1.38.2.16 2003/03/05 18:42:33 njl 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 <wpaul@ctr.columbia.edu>
 * 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 "opt_ifpoll.h"

#include <sys/param.h>
#include <sys/endian.h>
#include <sys/systm.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/socket.h>
#include <sys/serialize.h>
#include <sys/bus.h>
#include <sys/rman.h>
#include <sys/interrupt.h>

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

#include <net/bpf.h>

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

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

/* "controller miibus0" required.  See GENERIC if you get errors here. */
#include "miibus_if.h"

/*
 * Default to using PIO access for this driver. On SMP systems,
 * there appear to be problems with memory mapped mode: it looks like
 * doing too many memory mapped access back to back in rapid succession
 * can hang the bus. I'm inclined to blame this on crummy design/construction
 * on the part of RealTek. Memory mapped mode does appear to work on
 * uniprocessor systems though.
 */
#define RL_USEIOSPACE

#include <dev/netif/rl/if_rlreg.h>

/*
 * Various supported device vendors/types and their names.
 */
static struct rl_type {
        uint16_t         rl_vid;
        uint16_t         rl_did;
        const char      *rl_name;
} rl_devs[] = {
        { PCI_VENDOR_REALTEK, PCI_PRODUCT_REALTEK_RT8129,
                "RealTek 8129 10/100BaseTX" },
        { PCI_VENDOR_REALTEK, PCI_PRODUCT_REALTEK_RT8139,
                "RealTek 8139 10/100BaseTX" },
        { PCI_VENDOR_REALTEK, PCI_PRODUCT_REALTEK_RT8139B,
                "RealTek 8139 10/100BaseTX CardBus" },
        { PCI_VENDOR_ACCTON, PCI_PRODUCT_ACCTON_MPX5030,
                "Accton MPX 5030/5038 10/100BaseTX" },
        { PCI_VENDOR_DELTA, PCI_PRODUCT_DELTA_8139,
                "Delta Electronics 8139 10/100BaseTX" },
        { PCI_VENDOR_ADDTRON, PCI_PRODUCT_ADDTRON_8139,
                "Addtron Technology 8139 10/100BaseTX" },
        { PCI_VENDOR_DLINK, PCI_PRODUCT_DLINK_DFE520TX_C1,
                "D-Link DFE-520TX C1 10/100BaseTX" },
        { PCI_VENDOR_DLINK, PCI_PRODUCT_DLINK_DFE530TXPLUS,
                "D-Link DFE-530TX+ 10/100BaseTX" },
        { PCI_VENDOR_DLINK, PCI_PRODUCT_DLINK_DFE690TXD,
                "D-Link DFE-690TX 10/100BaseTX" },
        { PCI_VENDOR_NORTEL, PCI_PRODUCT_NORTEL_BAYSTACK_21,
                "Nortel Networks 10/100BaseTX" },
        { PCI_VENDOR_PEPPERCON, PCI_PRODUCT_PEPPERCON_ROLF,
                "Peppercon AG ROL/F" },
        { PCI_VENDOR_COREGA, PCI_PRODUCT_COREGA_CB_TXD,
                "Corega FEther CB-TXD" },
        { PCI_VENDOR_COREGA, PCI_PRODUCT_COREGA_2CB_TXD,
                "Corega FEtherII CB-TXD" },
        { PCI_VENDOR_PLANEX, PCI_PRODUCT_PLANEX_FNW_3800_TX,
                "Planex FNW-3800-TX" },
        { 0, 0, NULL }
};

static int      rl_probe(device_t);
static int      rl_attach(device_t);
static int      rl_detach(device_t);

static int      rl_encap(struct rl_softc *, struct mbuf * );

static void     rl_rxeof(struct rl_softc *);
static void     rl_txeof(struct rl_softc *);
static void     rl_intr(void *);
static void     rl_tick(void *);
static void     rl_start(struct ifnet *, struct ifaltq_subque *);
static int      rl_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
static void     rl_init(void *);
static void     rl_stop (struct rl_softc *);
static void     rl_watchdog(struct ifnet *);
static int      rl_suspend(device_t);
static int      rl_resume(device_t);
static void     rl_shutdown(device_t);
static int      rl_ifmedia_upd(struct ifnet *);
static void     rl_ifmedia_sts(struct ifnet *, struct ifmediareq *);

static void     rl_eeprom_putbyte(struct rl_softc *, int);
static void     rl_eeprom_getword(struct rl_softc *, int, uint16_t *);
static void     rl_read_eeprom(struct rl_softc *, caddr_t, int, int, int);
static void     rl_mii_sync(struct rl_softc *);
static void     rl_mii_send(struct rl_softc *, uint32_t, int);
static int      rl_mii_readreg(struct rl_softc *, struct rl_mii_frame *);
static int      rl_mii_writereg(struct rl_softc *, struct rl_mii_frame *);

static int      rl_miibus_readreg(device_t, int, int);
static int      rl_miibus_writereg(device_t, int, int, int);
static void     rl_miibus_statchg(device_t);

static void     rl_setmulti(struct rl_softc *);
static void     rl_reset(struct rl_softc *);
static void     rl_list_tx_init(struct rl_softc *);

#ifdef IFPOLL_ENABLE
static void     rl_npoll(struct ifnet *, struct ifpoll_info *);
static void     rl_npoll_compat(struct ifnet *, void *, int);
#endif

static int      rl_dma_alloc(struct rl_softc *);
static void     rl_dma_free(struct rl_softc *);

#ifdef RL_USEIOSPACE
#define RL_RES                  SYS_RES_IOPORT
#define RL_RID                  RL_PCI_LOIO
#else
#define RL_RES                  SYS_RES_MEMORY
#define RL_RID                  RL_PCI_LOMEM
#endif

static device_method_t rl_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         rl_probe),
        DEVMETHOD(device_attach,        rl_attach),
        DEVMETHOD(device_detach,        rl_detach),
        DEVMETHOD(device_suspend,       rl_suspend),
        DEVMETHOD(device_resume,        rl_resume),
        DEVMETHOD(device_shutdown,      rl_shutdown),

        /* bus interface */
        DEVMETHOD(bus_print_child,      bus_generic_print_child),
        DEVMETHOD(bus_driver_added,     bus_generic_driver_added),

        /* MII interface */
        DEVMETHOD(miibus_readreg,       rl_miibus_readreg),
        DEVMETHOD(miibus_writereg,      rl_miibus_writereg),
        DEVMETHOD(miibus_statchg,       rl_miibus_statchg),

        DEVMETHOD_END
};

static DEFINE_CLASS_0(rl, rl_driver, rl_methods, sizeof(struct rl_softc));
static devclass_t rl_devclass;

DECLARE_DUMMY_MODULE(if_rl);
DRIVER_MODULE(if_rl, pci, rl_driver, rl_devclass, NULL, NULL);
DRIVER_MODULE(if_rl, cardbus, rl_driver, rl_devclass, NULL, NULL);
DRIVER_MODULE(miibus, rl, miibus_driver, miibus_devclass, NULL, NULL);
MODULE_DEPEND(if_rl, miibus, 1, 1, 1);

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

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

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

        d = addr | sc->rl_eecmd_read;

        /*
         * Feed in each bit and strobe the clock.
         */
        for (i = 0x400; i; i >>= 1) {
                if (d & i)
                        EE_SET(RL_EE_DATAIN);
                else
                        EE_CLR(RL_EE_DATAIN);
                DELAY(100);
                EE_SET(RL_EE_CLK);
                DELAY(150);
                EE_CLR(RL_EE_CLK);
                DELAY(100);
        }
}

/*
 * Read a word of data stored in the EEPROM at address 'addr.'
 */
static void
rl_eeprom_getword(struct rl_softc *sc, int addr, uint16_t *dest)
{
        int i;
        uint16_t word = 0;

        /* Enter EEPROM access mode. */
        CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_PROGRAM|RL_EE_SEL);

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

        CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_PROGRAM|RL_EE_SEL);

        /*
         * Start reading bits from EEPROM.
         */
        for (i = 0x8000; i; i >>= 1) {
                EE_SET(RL_EE_CLK);
                DELAY(100);
                if (CSR_READ_1(sc, RL_EECMD) & RL_EE_DATAOUT)
                        word |= i;
                EE_CLR(RL_EE_CLK);
                DELAY(100);
        }

        /* Turn off EEPROM access mode. */
        CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);

        *dest = word;
}

/*
 * Read a sequence of words from the EEPROM.
 */
static void
rl_read_eeprom(struct rl_softc *sc, caddr_t dest, int off, int cnt, int swap)
{
        int i;
        u_int16_t word = 0, *ptr;

        for (i = 0; i < cnt; i++) {
                rl_eeprom_getword(sc, off + i, &word);
                ptr = (u_int16_t *)(dest + (i * 2));
                if (swap)
                        *ptr = ntohs(word);
                else
                        *ptr = 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 rl_phy_readreg()/rl_phy_writereg() to the
 * direct access PHY registers.
 */
#define MII_SET(x)                                                      \
        CSR_WRITE_1(sc, RL_MII, CSR_READ_1(sc, RL_MII) | x)

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

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

        MII_SET(RL_MII_DIR|RL_MII_DATAOUT);

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

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

        MII_CLR(RL_MII_CLK);

        for (i = (0x1 << (cnt - 1)); i; i >>= 1) {
                if (bits & i)
                        MII_SET(RL_MII_DATAOUT);
                else
                        MII_CLR(RL_MII_DATAOUT);
                DELAY(1);
                MII_CLR(RL_MII_CLK);
                DELAY(1);
                MII_SET(RL_MII_CLK);
        }
}

/*
 * Read an PHY register through the MII.
 */
static int
rl_mii_readreg(struct rl_softc *sc, struct rl_mii_frame *frame)
{
        int ack, i;

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

        CSR_WRITE_2(sc, RL_MII, 0);

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

        rl_mii_sync(sc);

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

        /* Idle bit */
        MII_CLR((RL_MII_CLK|RL_MII_DATAOUT));
        DELAY(1);
        MII_SET(RL_MII_CLK);
        DELAY(1);

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

        /* Check for ack */
        MII_CLR(RL_MII_CLK);
        DELAY(1);
        ack = CSR_READ_2(sc, RL_MII) & RL_MII_DATAIN;
        MII_SET(RL_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(RL_MII_CLK);
                        DELAY(1);
                        MII_SET(RL_MII_CLK);
                        DELAY(1);
                }
        } else {
                for (i = 0x8000; i; i >>= 1) {
                        MII_CLR(RL_MII_CLK);
                        DELAY(1);
                        if (!ack) {
                                if (CSR_READ_2(sc, RL_MII) & RL_MII_DATAIN)
                                        frame->mii_data |= i;
                                DELAY(1);
                        }
                        MII_SET(RL_MII_CLK);
                        DELAY(1);
                }
        }

        MII_CLR(RL_MII_CLK);
        DELAY(1);
        MII_SET(RL_MII_CLK);
        DELAY(1);

        return(ack ? 1 : 0);
}

/*
 * Write to a PHY register through the MII.
 */
static int
rl_mii_writereg(struct rl_softc *sc, struct rl_mii_frame *frame)
{
        /*
         * Set up frame for TX.
         */
        frame->mii_stdelim = RL_MII_STARTDELIM;
        frame->mii_opcode = RL_MII_WRITEOP;
        frame->mii_turnaround = RL_MII_TURNAROUND;

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

        rl_mii_sync(sc);

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

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

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

        return(0);
}

static int
rl_miibus_readreg(device_t dev, int phy, int reg)
{
        struct rl_softc *sc;
        struct rl_mii_frame frame;
        uint16_t rval = 0;
        uint16_t rl8139_reg = 0;

        sc = device_get_softc(dev);

        if (sc->rl_type == RL_8139) {
                /* Pretend the internal PHY is only at address 0 */
                if (phy)
                        return(0);
                switch (reg) {
                case MII_BMCR:
                        rl8139_reg = RL_BMCR;
                        break;
                case MII_BMSR:
                        rl8139_reg = RL_BMSR;
                        break;
                case MII_ANAR:
                        rl8139_reg = RL_ANAR;
                        break;
                case MII_ANER:
                        rl8139_reg = RL_ANER;
                        break;
                case MII_ANLPAR:
                        rl8139_reg = RL_LPAR;
                        break;
                case MII_PHYIDR1:
                case MII_PHYIDR2:
                        return(0);
                        break;
                /*
                 * Allow the rlphy driver to read the media status
                 * register. If we have a link partner which does not
                 * support NWAY, this is the register which will tell
                 * us the results of parallel detection.
                 */
                case RL_MEDIASTAT:
                        rval = CSR_READ_1(sc, RL_MEDIASTAT);
                        return(rval);
                default:
                        device_printf(dev, "bad phy register\n");
                        return(0);
                }
                rval = CSR_READ_2(sc, rl8139_reg);
                return(rval);
        }

        bzero(&frame, sizeof(frame));

        frame.mii_phyaddr = phy;
        frame.mii_regaddr = reg;
        rl_mii_readreg(sc, &frame);

        return(frame.mii_data);
}

static int
rl_miibus_writereg(device_t dev, int phy, int reg, int data)
{
        struct rl_softc *sc;
        struct rl_mii_frame frame;
        u_int16_t rl8139_reg = 0;

        sc = device_get_softc(dev);

        if (sc->rl_type == RL_8139) {
                /* Pretend the internal PHY is only at address 0 */
                if (phy)
                        return(0);
                switch (reg) {
                case MII_BMCR:
                        rl8139_reg = RL_BMCR;
                        break;
                case MII_BMSR:
                        rl8139_reg = RL_BMSR;
                        break;
                case MII_ANAR:
                        rl8139_reg = RL_ANAR;
                        break;
                case MII_ANER:
                        rl8139_reg = RL_ANER;
                        break;
                case MII_ANLPAR:
                        rl8139_reg = RL_LPAR;
                        break;
                case MII_PHYIDR1:
                case MII_PHYIDR2:
                        return(0);
                default:
                        device_printf(dev, "bad phy register\n");
                        return(0);
                }
                CSR_WRITE_2(sc, rl8139_reg, data);
                return(0);
        }

        bzero(&frame, sizeof(frame));

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

        rl_mii_writereg(sc, &frame);

        return(0);
}

static void
rl_miibus_statchg(device_t dev)
{
}

/*
 * Program the 64-bit multicast hash filter.
 */
static void
rl_setmulti(struct rl_softc *sc)
{
        struct ifnet *ifp;
        int h = 0;
        uint32_t hashes[2] = { 0, 0 };
        struct ifmultiaddr *ifma;
        uint32_t rxfilt;
        int mcnt = 0;

        ifp = &sc->arpcom.ac_if;

        rxfilt = CSR_READ_4(sc, RL_RXCFG);

        if (ifp->if_flags & IFF_ALLMULTI || ifp->if_flags & IFF_PROMISC) {
                rxfilt |= RL_RXCFG_RX_MULTI;
                CSR_WRITE_4(sc, RL_RXCFG, rxfilt);
                CSR_WRITE_4(sc, RL_MAR0, 0xFFFFFFFF);
                CSR_WRITE_4(sc, RL_MAR4, 0xFFFFFFFF);
                return;
        }

        /* first, zot all the existing hash bits */
        CSR_WRITE_4(sc, RL_MAR0, 0);
        CSR_WRITE_4(sc, RL_MAR4, 0);

        /* now program new ones */
        TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
                if (ifma->ifma_addr->sa_family != AF_LINK)
                        continue;
                h = ether_crc32_be(
                    LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
                    ETHER_ADDR_LEN) >> 26;
                if (h < 32)
                        hashes[0] |= (1 << h);
                else
                        hashes[1] |= (1 << (h - 32));
                mcnt++;
        }

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

        CSR_WRITE_4(sc, RL_RXCFG, rxfilt);
        CSR_WRITE_4(sc, RL_MAR0, hashes[0]);
        CSR_WRITE_4(sc, RL_MAR4, hashes[1]);
}

static void
rl_reset(struct rl_softc *sc)
{
        int i;

        CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_RESET);

        for (i = 0; i < RL_TIMEOUT; i++) {
                DELAY(10);
                if (!(CSR_READ_1(sc, RL_COMMAND) & RL_CMD_RESET))
                        break;
        }
        if (i == RL_TIMEOUT)
                device_printf(sc->rl_dev, "reset never completed!\n");
}

/*
 * Probe for a RealTek 8129/8139 chip. Check the PCI vendor and device
 * IDs against our list and return a device name if we find a match.
 *
 * Return with a value < 0 to give re(4) a change to attach.
 */
static int
rl_probe(device_t dev)
{
        struct rl_type *t;
        uint16_t product = pci_get_device(dev);
        uint16_t vendor = pci_get_vendor(dev);

        for (t = rl_devs; t->rl_name != NULL; t++) {
                if (vendor == t->rl_vid && product == t->rl_did) {
                        device_set_desc(dev, t->rl_name);
                        return(-100);
                }
        }

        return(ENXIO);
}

/*
 * Attach the interface. Allocate softc structures, do ifmedia
 * setup and ethernet/BPF attach.
 */
static int
rl_attach(device_t dev)
{
        uint8_t eaddr[ETHER_ADDR_LEN];
        uint16_t as[3];
        struct rl_softc *sc;
        struct ifnet *ifp;
        uint16_t rl_did = 0;
        int error = 0, rid, i;

        sc = device_get_softc(dev);
        sc->rl_dev = dev;

        /*
         * Handle power management nonsense.
         */

        if (pci_get_powerstate(dev) != PCI_POWERSTATE_D0) {
                uint32_t iobase, membase, irq;

                /* Save important PCI config data. */
                iobase = pci_read_config(dev, RL_PCI_LOIO, 4);
                membase = pci_read_config(dev, RL_PCI_LOMEM, 4);
                irq = pci_read_config(dev, RL_PCI_INTLINE, 4);

                /* Reset the power state. */
                device_printf(dev, "chip is in %s power mode "
                              "-- setting to D0\n",
                              pci_powerstate_to_str(pci_get_powerstate(dev)));
                pci_set_powerstate(dev, PCI_POWERSTATE_D0);

                /* Restore PCI config data. */
                pci_write_config(dev, RL_PCI_LOIO, iobase, 4);
                pci_write_config(dev, RL_PCI_LOMEM, membase, 4);
                pci_write_config(dev, RL_PCI_INTLINE, irq, 4);
        }

        pci_enable_busmaster(dev);

        rid = RL_RID;
        sc->rl_res = bus_alloc_resource_any(dev, RL_RES, &rid, RF_ACTIVE);

        if (sc->rl_res == NULL) {
                device_printf(dev, "couldn't map ports/memory\n");
                error = ENXIO;
                goto fail;
        }

        sc->rl_btag = rman_get_bustag(sc->rl_res);
        sc->rl_bhandle = rman_get_bushandle(sc->rl_res);

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

        if (sc->rl_irq == NULL) {
                device_printf(dev, "couldn't map interrupt\n");
                error = ENXIO;
                goto fail;
        }

        callout_init(&sc->rl_stat_timer);

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

        sc->rl_eecmd_read = RL_EECMD_READ_6BIT;
        rl_read_eeprom(sc, (uint8_t *)&rl_did, 0, 1, 0);
        if (rl_did != 0x8129)
                sc->rl_eecmd_read = RL_EECMD_READ_8BIT;

        /*
         * Get station address from the EEPROM.
         */
        rl_read_eeprom(sc, (caddr_t)as, RL_EE_EADDR, 3, 0);
        for (i = 0; i < 3; i++) {
                eaddr[(i * 2) + 0] = as[i] & 0xff;
                eaddr[(i * 2) + 1] = as[i] >> 8;
        }

        /*
         * Now read the exact device type from the EEPROM to find
         * out if it's an 8129 or 8139.
         */
        rl_read_eeprom(sc, (caddr_t)&rl_did, RL_EE_PCI_DID, 1, 0);

        if (rl_did == PCI_PRODUCT_REALTEK_RT8139 ||
            rl_did == PCI_PRODUCT_ACCTON_MPX5030 ||
            rl_did == PCI_PRODUCT_DELTA_8139 ||
            rl_did == PCI_PRODUCT_ADDTRON_8139 ||
            rl_did == PCI_PRODUCT_DLINK_DFE530TXPLUS ||
            rl_did == PCI_PRODUCT_REALTEK_RT8139B ||
            rl_did == PCI_PRODUCT_DLINK_DFE690TXD ||
            rl_did == PCI_PRODUCT_COREGA_CB_TXD ||
            rl_did == PCI_PRODUCT_COREGA_2CB_TXD ||
            rl_did == PCI_PRODUCT_PLANEX_FNW_3800_TX) {
                sc->rl_type = RL_8139;
        } else if (rl_did == PCI_PRODUCT_REALTEK_RT8129) {
                sc->rl_type = RL_8129;
        } else {
                device_printf(dev, "unknown device ID: %x\n", rl_did);
                sc->rl_type = RL_8139;
                /*
                 * Read RL_IDR register to get ethernet address as accessing
                 * EEPROM may not extract correct address.
                 */
                for (i = 0; i < ETHER_ADDR_LEN; i++)
                        eaddr[i] = CSR_READ_1(sc, RL_IDR0 + i);
        }

        error = rl_dma_alloc(sc);
        if (error)
                goto fail;

        /* Do MII setup */
        if (mii_phy_probe(dev, &sc->rl_miibus, rl_ifmedia_upd,
                          rl_ifmedia_sts)) {
                device_printf(dev, "MII without any phy!\n");
                error = ENXIO;
                goto fail;
        }

        ifp = &sc->arpcom.ac_if;
        ifp->if_softc = sc;
        if_initname(ifp, device_get_name(dev), device_get_unit(dev));
        ifp->if_mtu = ETHERMTU;
        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_ioctl = rl_ioctl;
        ifp->if_start = rl_start;
        ifp->if_watchdog = rl_watchdog;
        ifp->if_init = rl_init;
        ifp->if_baudrate = 10000000;
        ifp->if_capabilities = IFCAP_VLAN_MTU;
#ifdef IFPOLL_ENABLE
        ifp->if_npoll = rl_npoll;
#endif
        ifq_set_maxlen(&ifp->if_snd, IFQ_MAXLEN);
        ifq_set_ready(&ifp->if_snd);

        /*
         * Call MI attach routine.
         */
        ether_ifattach(ifp, eaddr, NULL);

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

#ifdef IFPOLL_ENABLE
        ifpoll_compat_setup(&sc->rl_npoll, NULL, NULL, device_get_unit(dev),
            ifp->if_serializer);
#endif

        error = bus_setup_intr(dev, sc->rl_irq, INTR_MPSAFE, rl_intr,
                               sc, &sc->rl_intrhand, ifp->if_serializer);

        if (error) {
                device_printf(dev, "couldn't set up irq\n");
                ether_ifdetach(ifp);
                goto fail;
        }

        return(0);

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

static int
rl_detach(device_t dev)
{
        struct rl_softc *sc;
        struct ifnet *ifp;

        sc = device_get_softc(dev);
        ifp = &sc->arpcom.ac_if;

        if (device_is_attached(dev)) {
                lwkt_serialize_enter(ifp->if_serializer);
                rl_stop(sc);
                bus_teardown_intr(dev, sc->rl_irq, sc->rl_intrhand);
                lwkt_serialize_exit(ifp->if_serializer);

                ether_ifdetach(ifp);
        }

        if (sc->rl_miibus)
                device_delete_child(dev, sc->rl_miibus);
        bus_generic_detach(dev);

        if (sc->rl_irq)
                bus_release_resource(dev, SYS_RES_IRQ, 0, sc->rl_irq);
        if (sc->rl_res)
                bus_release_resource(dev, RL_RES, RL_RID, sc->rl_res);

        rl_dma_free(sc);

        return(0);
}

/*
 * Initialize the transmit descriptors.
 */
static void
rl_list_tx_init(struct rl_softc *sc)
{
        struct rl_chain_data *cd;
        int i;

        cd = &sc->rl_cdata;
        for (i = 0; i < RL_TX_LIST_CNT; i++) {
                cd->rl_tx_chain[i] = NULL;
                CSR_WRITE_4(sc, RL_TXADDR0 + (i * sizeof(uint32_t)),
                            0x0000000);
        }

        sc->rl_cdata.cur_tx = 0;
        sc->rl_cdata.last_tx = 0;
}

/*
 * 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
 * when you have to use m_devget().
 *
 * 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 cheat a bit by copying from
 * the ring buffer starting at an address two bytes before the actual
 * data location. We can then shave off the first two bytes using m_adj().
 * The reason we do this is because m_devget() doesn't let us specify an
 * offset into the mbuf storage space, so we have to artificially create
 * one. The ring is allocated in such a way that there are a few unused
 * bytes of space preceecing it so that it will be safe for us to do the
 * 2-byte backstep even if reading from the ring at offset 0.
 */
static void
rl_rxeof(struct rl_softc *sc)
{
        struct mbuf *m;
        struct ifnet *ifp;
        int total_len = 0;
        uint32_t rxstat;
        caddr_t rxbufpos;
        int wrap = 0, done = 0;
        uint16_t cur_rx = 0, max_bytes = 0, rx_bytes = 0;

        ifp = &sc->arpcom.ac_if;

        while((CSR_READ_1(sc, RL_COMMAND) & RL_CMD_EMPTY_RXBUF) == 0) {
                if (!done) {
                        uint16_t limit;

                        done = 1;

                        cur_rx = (CSR_READ_2(sc, RL_CURRXADDR) + 16) %
                            RL_RXBUFLEN;

                        /* Do not try to read past this point. */
                        limit = CSR_READ_2(sc, RL_CURRXBUF) % RL_RXBUFLEN;
                        if (limit < cur_rx)
                                max_bytes = (RL_RXBUFLEN - cur_rx) + limit;
                        else
                                max_bytes = limit - cur_rx;
                }
#ifdef IFPOLL_ENABLE
                if (ifp->if_flags & IFF_NPOLLING) {
                        if (sc->rxcycles <= 0)
                                break;
                        sc->rxcycles--;
                }
#endif /* IFPOLL_ENABLE */
                rxbufpos = sc->rl_cdata.rl_rx_buf + cur_rx;
                rxstat = le32toh(*(uint32_t *)rxbufpos);

                /*
                 * 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.
                 */
                if ((uint16_t)(rxstat >> 16) == RL_RXSTAT_UNFINISHED)
                        break;

                if ((rxstat & RL_RXSTAT_RXOK) == 0) {
                        IFNET_STAT_INC(ifp, ierrors, 1);
                        rl_init(sc);
                        return;
                }

                /* No errors; receive the packet. */
                total_len = rxstat >> 16;
                rx_bytes += total_len + 4;

                /*
                 * XXX The RealTek chip includes the CRC with every
                 * received frame, and there's no way to turn this
                 * behavior off (at least, I can't find anything in
                 * the manual that explains how to do it) so we have
                 * to trim off the CRC manually.
                 */
                total_len -= ETHER_CRC_LEN;

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

                rxbufpos = sc->rl_cdata.rl_rx_buf +
                        ((cur_rx + sizeof(uint32_t)) % RL_RXBUFLEN);

                if (rxbufpos == (sc->rl_cdata.rl_rx_buf + RL_RXBUFLEN))
                        rxbufpos = sc->rl_cdata.rl_rx_buf;

                wrap = (sc->rl_cdata.rl_rx_buf + RL_RXBUFLEN) - rxbufpos;

                if (total_len > wrap) {
                        /*
                         * Fool m_devget() into thinking we want to copy
                         * the whole buffer so we don't end up fragmenting
                         * the data.
                         */
                        m = m_devget(rxbufpos - RL_ETHER_ALIGN,
                                     wrap + RL_ETHER_ALIGN, 0, ifp);
                        if (m == NULL) {
                                IFNET_STAT_INC(ifp, ierrors, 1);
                        } else {
                                m_adj(m, RL_ETHER_ALIGN);
                                m_copyback(m, wrap, total_len - wrap,
                                           sc->rl_cdata.rl_rx_buf);
                        }
                        cur_rx = (total_len - wrap + ETHER_CRC_LEN);
                } else {
                        m = m_devget(rxbufpos - RL_ETHER_ALIGN,
                                     total_len + RL_ETHER_ALIGN, 0, ifp);
                        if (m == NULL) {
                                IFNET_STAT_INC(ifp, ierrors, 1);
                        } else
                                m_adj(m, RL_ETHER_ALIGN);
                        cur_rx += total_len + 4 + ETHER_CRC_LEN;
                }

                /*
                 * Round up to 32-bit boundary.
                 */
                cur_rx = (cur_rx + 3) & ~3;
                CSR_WRITE_2(sc, RL_CURRXADDR, cur_rx - 16);

                if (m == NULL)
                        continue;

                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
rl_txeof(struct rl_softc *sc)
{
        struct ifnet *ifp;
        uint32_t txstat;

        ifp = &sc->arpcom.ac_if;

        /*
         * Go through our tx list and free mbufs for those
         * frames that have been uploaded.
         */
        do {
                if (RL_LAST_TXMBUF(sc) == NULL)
                        break;
                txstat = CSR_READ_4(sc, RL_LAST_TXSTAT(sc));
                if ((txstat & (RL_TXSTAT_TX_OK | RL_TXSTAT_TX_UNDERRUN |
                               RL_TXSTAT_TXABRT)) == 0)
                        break;

                IFNET_STAT_INC(ifp, collisions,
                    (txstat & RL_TXSTAT_COLLCNT) >> 24);

                bus_dmamap_unload(sc->rl_cdata.rl_tx_tag, RL_LAST_DMAMAP(sc));
                m_freem(RL_LAST_TXMBUF(sc));
                RL_LAST_TXMBUF(sc) = NULL;
                RL_INC(sc->rl_cdata.last_tx);

                if (txstat & RL_TXSTAT_TX_UNDERRUN) {
                        sc->rl_txthresh += 32;
                        if (sc->rl_txthresh > RL_TX_THRESH_MAX)
                                sc->rl_txthresh = RL_TX_THRESH_MAX;
                }

                if (txstat & RL_TXSTAT_TX_OK) {
                        IFNET_STAT_INC(ifp, opackets, 1);
                } else {
                        IFNET_STAT_INC(ifp, oerrors, 1);
                        if (txstat & (RL_TXSTAT_TXABRT | RL_TXSTAT_OUTOFWIN))
                                CSR_WRITE_4(sc, RL_TXCFG, RL_TXCFG_CONFIG);
                }
                ifq_clr_oactive(&ifp->if_snd);
        } while (sc->rl_cdata.last_tx != sc->rl_cdata.cur_tx);

        if (RL_LAST_TXMBUF(sc) == NULL)
                ifp->if_timer = 0;
        else if (ifp->if_timer == 0)
                ifp->if_timer = 5;
}

static void
rl_tick(void *xsc)
{
        struct rl_softc *sc = xsc;
        struct mii_data *mii;

        lwkt_serialize_enter(sc->arpcom.ac_if.if_serializer);

        mii = device_get_softc(sc->rl_miibus);
        mii_tick(mii);

        callout_reset(&sc->rl_stat_timer, hz, rl_tick, sc);

        lwkt_serialize_exit(sc->arpcom.ac_if.if_serializer);
}

#ifdef IFPOLL_ENABLE

static void
rl_npoll_compat(struct ifnet *ifp, void *arg __unused, int count)
{
        struct rl_softc *sc = ifp->if_softc;

        ASSERT_SERIALIZED(ifp->if_serializer);

        sc->rxcycles = count;
        rl_rxeof(sc);
        rl_txeof(sc);
        if (!ifq_is_empty(&ifp->if_snd))
                if_devstart(ifp);

        if (sc->rl_npoll.ifpc_stcount-- == 0) {
                uint16_t status;

                sc->rl_npoll.ifpc_stcount = sc->rl_npoll.ifpc_stfrac;

                status = CSR_READ_2(sc, RL_ISR);
                if (status == 0xffff)
                        return;
                if (status)
                        CSR_WRITE_2(sc, RL_ISR, status);

                /*
                 * XXX check behaviour on receiver stalls.
                 */

                if (status & RL_ISR_SYSTEM_ERR) {
                        rl_reset(sc);
                        rl_init(sc);
                }
        }
}

static void
rl_npoll(struct ifnet *ifp, struct ifpoll_info *info)
{
        struct rl_softc *sc = ifp->if_softc;

        ASSERT_SERIALIZED(ifp->if_serializer);

        if (info != NULL) {
                int cpuid = sc->rl_npoll.ifpc_cpuid;

                info->ifpi_rx[cpuid].poll_func = rl_npoll_compat;
                info->ifpi_rx[cpuid].arg = NULL;
                info->ifpi_rx[cpuid].serializer = ifp->if_serializer;

                if (ifp->if_flags & IFF_RUNNING) {
                        /* disable interrupts */
                        CSR_WRITE_2(sc, RL_IMR, 0x0000);
                        sc->rl_npoll.ifpc_stcount = 0;
                }
                ifq_set_cpuid(&ifp->if_snd, cpuid);
        } else {
                if (ifp->if_flags & IFF_RUNNING) {
                        /* enable interrupts */
                        CSR_WRITE_2(sc, RL_IMR, RL_INTRS);
                }
                ifq_set_cpuid(&ifp->if_snd, rman_get_cpuid(sc->rl_irq));
        }
}

#endif /* IFPOLL_ENABLE */

static void
rl_intr(void *arg)
{
        struct rl_softc *sc;
        struct ifnet *ifp;
        uint16_t status;

        sc = arg;

        if (sc->suspended)
                return;

        ifp = &sc->arpcom.ac_if;

        for (;;) {
                status = CSR_READ_2(sc, RL_ISR);
                /* If the card has gone away, the read returns 0xffff. */
                if (status == 0xffff)
                        break;

                if (status != 0)
                        CSR_WRITE_2(sc, RL_ISR, status);

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

                if (status & RL_ISR_RX_OK)
                        rl_rxeof(sc);

                if (status & RL_ISR_RX_ERR)
                        rl_rxeof(sc);

                if ((status & RL_ISR_TX_OK) || (status & RL_ISR_TX_ERR))
                        rl_txeof(sc);

                if (status & RL_ISR_SYSTEM_ERR) {
                        rl_reset(sc);
                        rl_init(sc);
                }

        }

        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
rl_encap(struct rl_softc *sc, struct mbuf *m_head)
{
        struct mbuf *m_new = NULL;
        bus_dma_segment_t seg;
        int nseg, error;

        /*
         * The RealTek is brain damaged and wants longword-aligned
         * TX buffers, plus we can only have one fragment buffer
         * per packet.  We have to copy pretty much all the time.
         */
        m_new = m_defrag(m_head, M_NOWAIT);
        if (m_new == NULL) {
                m_freem(m_head);
                return ENOBUFS;
        }
        m_head = m_new;

        /* Pad frames to at least 60 bytes. */
        if (m_head->m_pkthdr.len < RL_MIN_FRAMELEN) {
                error = m_devpad(m_head, RL_MIN_FRAMELEN);
                if (error) {
                        m_freem(m_head);
                        return error;
                }
        }

        /* Extract physical address. */
        error = bus_dmamap_load_mbuf_segment(sc->rl_cdata.rl_tx_tag,
                        RL_CUR_DMAMAP(sc), m_head,
                        &seg, 1, &nseg, BUS_DMA_NOWAIT);
        if (error) {
                m_freem(m_head);
                return error;
        }

        /* Sync the loaded TX buffer. */
        bus_dmamap_sync(sc->rl_cdata.rl_tx_tag, RL_CUR_DMAMAP(sc),
                        BUS_DMASYNC_PREWRITE);

        /* Transmit */
        CSR_WRITE_4(sc, RL_CUR_TXADDR(sc), seg.ds_addr);
        CSR_WRITE_4(sc, RL_CUR_TXSTAT(sc),
                    RL_TXTHRESH(sc->rl_txthresh) | seg.ds_len);

        RL_CUR_TXMBUF(sc) = m_head;
        return 0;
}

/*
 * Main transmit routine.
 */

static void
rl_start(struct ifnet *ifp, struct ifaltq_subque *ifsq)
{
        struct rl_softc *sc = ifp->if_softc;
        struct mbuf *m_head = NULL;

        ASSERT_ALTQ_SQ_DEFAULT(ifp, ifsq);

        if ((ifp->if_flags & IFF_RUNNING) == 0 || ifq_is_oactive(&ifp->if_snd))
                return;

        while (RL_CUR_TXMBUF(sc) == NULL) {
                m_head = ifq_dequeue(&ifp->if_snd);
                if (m_head == NULL)
                        break;

                if (rl_encap(sc, m_head))
                        continue;

                /*
                 * If there's a BPF listener, bounce a copy of this frame
                 * to him.
                 */
                BPF_MTAP(ifp, RL_CUR_TXMBUF(sc));

                RL_INC(sc->rl_cdata.cur_tx);

                /*
                 * 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 (RL_CUR_TXMBUF(sc) != NULL)
                ifq_set_oactive(&ifp->if_snd);
}

static void
rl_init(void *xsc)
{
        struct rl_softc *sc = xsc;
        struct ifnet *ifp = &sc->arpcom.ac_if;
        struct mii_data *mii;
        uint32_t rxcfg = 0;

        mii = device_get_softc(sc->rl_miibus);

        /*
         * Cancel pending I/O and free all RX/TX buffers.
         */
        rl_stop(sc);

        /*
         * Init our MAC address.  Even though the chipset documentation
         * doesn't mention it, we need to enter "Config register write enable"
         * mode to modify the ID registers.
         */
        CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_WRITECFG);
        CSR_WRITE_STREAM_4(sc, RL_IDR0,
                           *(uint32_t *)(&sc->arpcom.ac_enaddr[0]));
        CSR_WRITE_STREAM_4(sc, RL_IDR4,
                           *(uint32_t *)(&sc->arpcom.ac_enaddr[4]));
        CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);

        /* Init the RX buffer pointer register. */
        CSR_WRITE_4(sc, RL_RXADDR, sc->rl_cdata.rl_rx_buf_paddr);

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

        /*
         * Enable transmit and receive.
         */
        CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_TX_ENB|RL_CMD_RX_ENB);

        /*
         * Set the initial TX and RX configuration.
         */
        CSR_WRITE_4(sc, RL_TXCFG, RL_TXCFG_CONFIG);
        CSR_WRITE_4(sc, RL_RXCFG, RL_RXCFG_CONFIG);

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

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

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

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

#ifdef IFPOLL_ENABLE
        /*
         * Only enable interrupts if we are polling, keep them off otherwise.
         */
        if (ifp->if_flags & IFF_NPOLLING) {
                CSR_WRITE_2(sc, RL_IMR, 0);
                sc->rl_npoll.ifpc_stcount = 0;
        } else
#endif /* IFPOLL_ENABLE */
        /*
         * Enable interrupts.
         */
        CSR_WRITE_2(sc, RL_IMR, RL_INTRS);

        /* Set initial TX threshold */
        sc->rl_txthresh = RL_TX_THRESH_INIT;

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

        /* Enable receiver and transmitter. */
        CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_TX_ENB|RL_CMD_RX_ENB);

        mii_mediachg(mii);

        CSR_WRITE_1(sc, RL_CFG1, RL_CFG1_DRVLOAD|RL_CFG1_FULLDUPLEX);

        ifp->if_flags |= IFF_RUNNING;
        ifq_clr_oactive(&ifp->if_snd);

        callout_reset(&sc->rl_stat_timer, hz, rl_tick, sc);
}

/*
 * Set media options.
 */
static int
rl_ifmedia_upd(struct ifnet *ifp)
{
        struct rl_softc *sc;
        struct mii_data *mii;

        sc = ifp->if_softc;
        mii = device_get_softc(sc->rl_miibus);
        mii_mediachg(mii);

        return(0);
}

/*
 * Report current media status.
 */
static void
rl_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
{
        struct rl_softc *sc = ifp->if_softc;
        struct mii_data *mii = device_get_softc(sc->rl_miibus);

        mii_pollstat(mii);
        ifmr->ifm_active = mii->mii_media_active;
        ifmr->ifm_status = mii->mii_media_status;
}

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

        switch (command) {
        case SIOCSIFFLAGS:
                if (ifp->if_flags & IFF_UP) {
                        rl_init(sc);
                } else {
                        if (ifp->if_flags & IFF_RUNNING)
                                rl_stop(sc);
                }
                error = 0;
                break;
        case SIOCADDMULTI:
        case SIOCDELMULTI:
                rl_setmulti(sc);
                error = 0;
                break;
        case SIOCGIFMEDIA:
        case SIOCSIFMEDIA:
                mii = device_get_softc(sc->rl_miibus);
                error = ifmedia_ioctl(ifp, ifr, &mii->mii_media, command);
                break;
        case SIOCSIFCAP:
                break;
        default:
                error = ether_ioctl(ifp, command, data);
                break;
        }

        return(error);
}

static void
rl_watchdog(struct ifnet *ifp)
{
        struct rl_softc *sc = ifp->if_softc;

        device_printf(sc->rl_dev, "watchdog timeout\n");

        IFNET_STAT_INC(ifp, oerrors, 1);

        rl_txeof(sc);
        rl_rxeof(sc);
        rl_init(sc);
}

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

        ifp->if_timer = 0;

        callout_stop(&sc->rl_stat_timer);
        ifp->if_flags &= ~IFF_RUNNING;
        ifq_clr_oactive(&ifp->if_snd);

        CSR_WRITE_1(sc, RL_COMMAND, 0x00);
        CSR_WRITE_2(sc, RL_IMR, 0x0000);

        /*
         * Free the TX list buffers.
         */
        for (i = 0; i < RL_TX_LIST_CNT; i++) {
                if (sc->rl_cdata.rl_tx_chain[i] != NULL) {
                        bus_dmamap_unload(sc->rl_cdata.rl_tx_tag,
                                          sc->rl_cdata.rl_tx_dmamap[i]);
                        m_freem(sc->rl_cdata.rl_tx_chain[i]);
                        sc->rl_cdata.rl_tx_chain[i] = NULL;
                        CSR_WRITE_4(sc, RL_TXADDR0 + (i * sizeof(uint32_t)),
                                    0x0000000);
                }
        }
}

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

        sc = device_get_softc(dev);
        lwkt_serialize_enter(sc->arpcom.ac_if.if_serializer);
        rl_stop(sc);
        lwkt_serialize_exit(sc->arpcom.ac_if.if_serializer);
}

/*
 * Device suspend routine.  Stop the interface and save some PCI
 * settings in case the BIOS doesn't restore them properly on
 * resume.
 */
static int
rl_suspend(device_t dev)
{
        struct rl_softc *sc = device_get_softc(dev);
        int i;

        lwkt_serialize_enter(sc->arpcom.ac_if.if_serializer);
        rl_stop(sc);

        for (i = 0; i < 5; i++)
                sc->saved_maps[i] = pci_read_config(dev, PCIR_BAR(i), 4);
        sc->saved_biosaddr = pci_read_config(dev, PCIR_BIOS, 4);
        sc->saved_intline = pci_read_config(dev, PCIR_INTLINE, 1);
        sc->saved_cachelnsz = pci_read_config(dev, PCIR_CACHELNSZ, 1);
        sc->saved_lattimer = pci_read_config(dev, PCIR_LATTIMER, 1);

        sc->suspended = 1;

        lwkt_serialize_exit(sc->arpcom.ac_if.if_serializer);
        return (0);
}

/*
 * Device resume routine.  Restore some PCI settings in case the BIOS
 * doesn't, re-enable busmastering, and restart the interface if
 * appropriate.
 */
static int
rl_resume(device_t dev)
{
        struct rl_softc *sc = device_get_softc(dev);
        struct ifnet *ifp = &sc->arpcom.ac_if;
        int             i;

        lwkt_serialize_enter(ifp->if_serializer);

        /* better way to do this? */
        for (i = 0; i < 5; i++)
                pci_write_config(dev, PCIR_BAR(i), sc->saved_maps[i], 4);
        pci_write_config(dev, PCIR_BIOS, sc->saved_biosaddr, 4);
        pci_write_config(dev, PCIR_INTLINE, sc->saved_intline, 1);
        pci_write_config(dev, PCIR_CACHELNSZ, sc->saved_cachelnsz, 1);
        pci_write_config(dev, PCIR_LATTIMER, sc->saved_lattimer, 1);

        /* reenable busmastering */
        pci_enable_busmaster(dev);
        pci_enable_io(dev, RL_RES);

        /* reinitialize interface if necessary */
        if (ifp->if_flags & IFF_UP)
                rl_init(sc);

        sc->suspended = 0;
        lwkt_serialize_exit(ifp->if_serializer);
        return (0);
}

static int
rl_dma_alloc(struct rl_softc *sc)
{
        bus_dmamem_t dmem;
        int error, i;

        error = bus_dma_tag_create(NULL,        /* parent */
                        1, 0,                   /* alignment, boundary */
                        BUS_SPACE_MAXADDR_32BIT,/* lowaddr */
                        BUS_SPACE_MAXADDR,      /* highaddr */
                        BUS_SPACE_MAXSIZE_32BIT,/* maxsize */
                        0,                      /* nsegments */
                        BUS_SPACE_MAXSIZE_32BIT,/* maxsegsize */
                        0,                      /* flags */
                        &sc->rl_parent_tag);
        if (error) {
                device_printf(sc->rl_dev, "can't create parent tag\n");
                return error;
        }

        /* Allocate a chunk of coherent memory for RX */
        error = bus_dmamem_coherent(sc->rl_parent_tag, 1, 0,
                        BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR,
                        RL_RXBUFLEN + 1518, BUS_DMA_WAITOK, &dmem);
        if (error)
                return error;

        sc->rl_cdata.rl_rx_tag = dmem.dmem_tag;
        sc->rl_cdata.rl_rx_dmamap = dmem.dmem_map;
        sc->rl_cdata.rl_rx_buf_ptr = dmem.dmem_addr;

        /* NOTE: Apply same adjustment to vaddr and paddr */
        sc->rl_cdata.rl_rx_buf = sc->rl_cdata.rl_rx_buf_ptr + sizeof(uint64_t);
        sc->rl_cdata.rl_rx_buf_paddr = dmem.dmem_busaddr + sizeof(uint64_t);

        /*
         * Allocate TX mbuf's DMA tag and maps
         */
        error = bus_dma_tag_create(sc->rl_parent_tag,/* parent */
                        RL_TXBUF_ALIGN, 0,      /* alignment, boundary */
                        BUS_SPACE_MAXADDR,      /* lowaddr */
                        BUS_SPACE_MAXADDR,      /* highaddr */
                        MCLBYTES,               /* maxsize */
                        1,                      /* nsegments */
                        MCLBYTES,               /* maxsegsize */
                        BUS_DMA_ALLOCNOW | BUS_DMA_WAITOK |
                        BUS_DMA_ALIGNED,        /* flags */
                        &sc->rl_cdata.rl_tx_tag);
        if (error) {
                device_printf(sc->rl_dev, "can't create TX mbuf tag\n");
                return error;
        }

        for (i = 0; i < RL_TX_LIST_CNT; ++i) {
                error = bus_dmamap_create(sc->rl_cdata.rl_tx_tag,
                                BUS_DMA_WAITOK, &sc->rl_cdata.rl_tx_dmamap[i]);
                if (error) {
                        int j;

                        for (j = 0; j < i; ++j) {
                                bus_dmamap_destroy(sc->rl_cdata.rl_tx_tag,
                                        sc->rl_cdata.rl_tx_dmamap[j]);
                        }
                        bus_dma_tag_destroy(sc->rl_cdata.rl_tx_tag);
                        sc->rl_cdata.rl_tx_tag = NULL;

                        device_printf(sc->rl_dev, "can't create TX mbuf map\n");
                        return error;
                }
        }
        return 0;
}

static void
rl_dma_free(struct rl_softc *sc)
{
        if (sc->rl_cdata.rl_tx_tag != NULL) {
                int i;

                for (i = 0; i < RL_TX_LIST_CNT; ++i) {
                        bus_dmamap_destroy(sc->rl_cdata.rl_tx_tag,
                                           sc->rl_cdata.rl_tx_dmamap[i]);
                }
                bus_dma_tag_destroy(sc->rl_cdata.rl_tx_tag);
        }

        if (sc->rl_cdata.rl_rx_tag != NULL) {
                bus_dmamap_unload(sc->rl_cdata.rl_rx_tag,
                                  sc->rl_cdata.rl_rx_dmamap);
                /* NOTE: Use rl_rx_buf_ptr here */
                bus_dmamem_free(sc->rl_cdata.rl_rx_tag,
                                sc->rl_cdata.rl_rx_buf_ptr,
                                sc->rl_cdata.rl_rx_dmamap);
                bus_dma_tag_destroy(sc->rl_cdata.rl_rx_tag);
        }

        if (sc->rl_parent_tag)
                bus_dma_tag_destroy(sc->rl_parent_tag);
}