text: /*-
   * 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.
   */
  
  #include <sys/cdefs.h>
  __FBSDID("$FreeBSD$");
  
  /*
   * 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.
   */
  
  #ifdef HAVE_KERNEL_OPTION_HEADERS
  #include "opt_device_polling.h"
  #endif
  
  #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/sysctl.h>
  
  #include <net/if.h>
  #include <net/if_var.h>
  #include <net/if_arp.h>
  #include <net/ethernet.h>
  #include <net/if_dl.h>
  #include <net/if_media.h>
  #include <net/if_types.h>
  
  #include <net/bpf.h>
  
  #include <machine/bus.h>
  #include <machine/resource.h>
  #include <sys/bus.h>
  #include <sys/rman.h>
  
  #include <dev/mii/mii.h>
  #include <dev/mii/mii_bitbang.h>
  #include <dev/mii/miivar.h>
  
  #include <dev/pci/pcireg.h>
  #include <dev/pci/pcivar.h>
  
  MODULE_DEPEND(rl, pci, 1, 1, 1);
  MODULE_DEPEND(rl, ether, 1, 1, 1);
  MODULE_DEPEND(rl, miibus, 1, 1, 1);
  
  /* "device miibus" required.  See GENERIC if you get errors here. */
  #include "miibus_if.h"
  
  #include <dev/rl/if_rlreg.h>
  
  /*
   * Various supported device vendors/types and their names.
   */
  static const struct rl_type rl_devs[] = {
  	{ RT_VENDORID, RT_DEVICEID_8129, RL_8129,
  		"RealTek 8129 10/100BaseTX" },
  	{ RT_VENDORID, RT_DEVICEID_8139, RL_8139,
  		"RealTek 8139 10/100BaseTX" },
  	{ RT_VENDORID, RT_DEVICEID_8139D, RL_8139,
  		"RealTek 8139 10/100BaseTX" },
  	{ RT_VENDORID, RT_DEVICEID_8138, RL_8139,
  		"RealTek 8139 10/100BaseTX CardBus" },
  	{ RT_VENDORID, RT_DEVICEID_8100, RL_8139,
  		"RealTek 8100 10/100BaseTX" },
  	{ ACCTON_VENDORID, ACCTON_DEVICEID_5030, RL_8139,
  		"Accton MPX 5030/5038 10/100BaseTX" },
  	{ DELTA_VENDORID, DELTA_DEVICEID_8139, RL_8139,
  		"Delta Electronics 8139 10/100BaseTX" },
  	{ ADDTRON_VENDORID, ADDTRON_DEVICEID_8139, RL_8139,
  		"Addtron Technology 8139 10/100BaseTX" },
  	{ DLINK_VENDORID, DLINK_DEVICEID_520TX_REVC1, RL_8139,
  		"D-Link DFE-520TX (rev. C1) 10/100BaseTX" },
  	{ DLINK_VENDORID, DLINK_DEVICEID_530TXPLUS, RL_8139,
  		"D-Link DFE-530TX+ 10/100BaseTX" },
  	{ DLINK_VENDORID, DLINK_DEVICEID_690TXD, RL_8139,
  		"D-Link DFE-690TXD 10/100BaseTX" },
  	{ NORTEL_VENDORID, ACCTON_DEVICEID_5030, RL_8139,
  		"Nortel Networks 10/100BaseTX" },
  	{ COREGA_VENDORID, COREGA_DEVICEID_FETHERCBTXD, RL_8139,
  		"Corega FEther CB-TXD" },
  	{ COREGA_VENDORID, COREGA_DEVICEID_FETHERIICBTXD, RL_8139,
  		"Corega FEtherII CB-TXD" },
  	{ PEPPERCON_VENDORID, PEPPERCON_DEVICEID_ROLF, RL_8139,
  		"Peppercon AG ROL-F" },
  	{ PLANEX_VENDORID, PLANEX_DEVICEID_FNW3603TX, RL_8139,
  		"Planex FNW-3603-TX" },
  	{ PLANEX_VENDORID, PLANEX_DEVICEID_FNW3800TX, RL_8139,
  		"Planex FNW-3800-TX" },
  	{ CP_VENDORID, RT_DEVICEID_8139, RL_8139,
  		"Compaq HNE-300" },
  	{ LEVEL1_VENDORID, LEVEL1_DEVICEID_FPC0106TX, RL_8139,
  		"LevelOne FPC-0106TX" },
  	{ EDIMAX_VENDORID, EDIMAX_DEVICEID_EP4103DL, RL_8139,
  		"Edimax EP-4103DL CardBus" }
  };
  
  static int rl_attach(device_t);
  static int rl_detach(device_t);
  static void rl_dmamap_cb(void *, bus_dma_segment_t *, int, int);
  static int rl_dma_alloc(struct rl_softc *);
  static void rl_dma_free(struct rl_softc *);
  static void rl_eeprom_putbyte(struct rl_softc *, int);
  static void rl_eeprom_getword(struct rl_softc *, int, uint16_t *);
  static int rl_encap(struct rl_softc *, struct mbuf **);
  static int rl_list_tx_init(struct rl_softc *);
  static int rl_list_rx_init(struct rl_softc *);
  static int rl_ifmedia_upd(struct ifnet *);
  static void rl_ifmedia_sts(struct ifnet *, struct ifmediareq *);
  static int rl_ioctl(struct ifnet *, u_long, caddr_t);
  static void rl_intr(void *);
  static void rl_init(void *);
  static void rl_init_locked(struct rl_softc *sc);
  static int rl_miibus_readreg(device_t, int, int);
  static void rl_miibus_statchg(device_t);
  static int rl_miibus_writereg(device_t, int, int, int);
  #ifdef DEVICE_POLLING
  static int rl_poll(struct ifnet *ifp, enum poll_cmd cmd, int count);
  static int rl_poll_locked(struct ifnet *ifp, enum poll_cmd cmd, int count);
  #endif
  static int rl_probe(device_t);
  static void rl_read_eeprom(struct rl_softc *, uint8_t *, int, int, int);
  static void rl_reset(struct rl_softc *);
  static int rl_resume(device_t);
  static int rl_rxeof(struct rl_softc *);
  static void rl_rxfilter(struct rl_softc *);
  static int rl_shutdown(device_t);
  static void rl_start(struct ifnet *);
  static void rl_start_locked(struct ifnet *);
  static void rl_stop(struct rl_softc *);
  static int rl_suspend(device_t);
  static void rl_tick(void *);
  static void rl_txeof(struct rl_softc *);
  static void rl_watchdog(struct rl_softc *);
  static void rl_setwol(struct rl_softc *);
  static void rl_clrwol(struct rl_softc *);
  
  /*
   * MII bit-bang glue
   */
  static uint32_t rl_mii_bitbang_read(device_t);
  static void rl_mii_bitbang_write(device_t, uint32_t);
  
  static const struct mii_bitbang_ops rl_mii_bitbang_ops = {
  	rl_mii_bitbang_read,
  	rl_mii_bitbang_write,
  	{
  		RL_MII_DATAOUT,	/* MII_BIT_MDO */
  		RL_MII_DATAIN,	/* MII_BIT_MDI */
  		RL_MII_CLK,	/* MII_BIT_MDC */
  		RL_MII_DIR,	/* MII_BIT_DIR_HOST_PHY */
  		0,		/* MII_BIT_DIR_PHY_HOST */
  	}
  };
  
  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),
  
  	/* MII interface */
  	DEVMETHOD(miibus_readreg,	rl_miibus_readreg),
  	DEVMETHOD(miibus_writereg,	rl_miibus_writereg),
  	DEVMETHOD(miibus_statchg,	rl_miibus_statchg),
  
  	DEVMETHOD_END
  };
  
  static driver_t rl_driver = {
  	"rl",
  	rl_methods,
  	sizeof(struct rl_softc)
  };
  
  static devclass_t rl_devclass;
  
  DRIVER_MODULE(rl, pci, rl_driver, rl_devclass, 0, 0);
  DRIVER_MODULE(rl, cardbus, rl_driver, rl_devclass, 0, 0);
  DRIVER_MODULE(miibus, rl, miibus_driver, miibus_devclass, 0, 0);
  
  #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)
  {
  	register 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)
  {
  	register 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, uint8_t *dest, int off, int cnt, int swap)
  {
  	int			i;
  	uint16_t		word = 0, *ptr;
  
  	for (i = 0; i < cnt; i++) {
  		rl_eeprom_getword(sc, off + i, &word);
  		ptr = (uint16_t *)(dest + (i * 2));
  		if (swap)
  			*ptr = ntohs(word);
  		else
  			*ptr = word;
  	}
  }
  
  /*
   * Read the MII serial port for the MII bit-bang module.
   */
  static uint32_t
  rl_mii_bitbang_read(device_t dev)
  {
  	struct rl_softc *sc;
  	uint32_t val;
  
  	sc = device_get_softc(dev);
  
  	val = CSR_READ_1(sc, RL_MII);
  	CSR_BARRIER(sc, RL_MII, 1,
  	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
  
  	return (val);
  }
  
  /*
   * Write the MII serial port for the MII bit-bang module.
   */
  static void
  rl_mii_bitbang_write(device_t dev, uint32_t val)
  {
  	struct rl_softc *sc;
  
  	sc = device_get_softc(dev);
  
  	CSR_WRITE_1(sc, RL_MII, val);
  	CSR_BARRIER(sc, RL_MII, 1,
  	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
  }
  
  static int
  rl_miibus_readreg(device_t dev, int phy, int reg)
  {
  	struct rl_softc		*sc;
  	uint16_t		rl8139_reg;
  
  	sc = device_get_softc(dev);
  
  	if (sc->rl_type == RL_8139) {
  		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);
  		/*
  		 * 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:
  			return (CSR_READ_1(sc, RL_MEDIASTAT));
  		default:
  			device_printf(sc->rl_dev, "bad phy register\n");
  			return (0);
  		}
  		return (CSR_READ_2(sc, rl8139_reg));
  	}
  
  	return (mii_bitbang_readreg(dev, &rl_mii_bitbang_ops, phy, reg));
  }
  
  static int
  rl_miibus_writereg(device_t dev, int phy, int reg, int data)
  {
  	struct rl_softc		*sc;
  	uint16_t		rl8139_reg;
  
  	sc = device_get_softc(dev);
  
  	if (sc->rl_type == RL_8139) {
  		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;
  		default:
  			device_printf(sc->rl_dev, "bad phy register\n");
  			return (0);
  		}
  		CSR_WRITE_2(sc, rl8139_reg, data);
  		return (0);
  	}
  
  	mii_bitbang_writereg(dev, &rl_mii_bitbang_ops, phy, reg, data);
  
  	return (0);
  }
  
  static void
  rl_miibus_statchg(device_t dev)
  {
  	struct rl_softc		*sc;
  	struct ifnet		*ifp;
  	struct mii_data		*mii;
  
  	sc = device_get_softc(dev);
  	mii = device_get_softc(sc->rl_miibus);
  	ifp = sc->rl_ifp;
  	if (mii == NULL || ifp == NULL ||
  	    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
  		return;
  
  	sc->rl_flags &= ~RL_FLAG_LINK;
  	if ((mii->mii_media_status & (IFM_ACTIVE | IFM_AVALID)) ==
  	    (IFM_ACTIVE | IFM_AVALID)) {
  		switch (IFM_SUBTYPE(mii->mii_media_active)) {
  		case IFM_10_T:
  		case IFM_100_TX:
  			sc->rl_flags |= RL_FLAG_LINK;
  			break;
  		default:
  			break;
  		}
  	}
  	/*
  	 * RealTek controllers do not provide any interface to
  	 * Tx/Rx MACs for resolved speed, duplex and flow-control
  	 * parameters.
  	 */
  }
  
  /*
   * Program the 64-bit multicast hash filter.
   */
  static void
  rl_rxfilter(struct rl_softc *sc)
  {
  	struct ifnet		*ifp = sc->rl_ifp;
  	int			h = 0;
  	uint32_t		hashes[2] = { 0, 0 };
  	struct ifmultiaddr	*ifma;
  	uint32_t		rxfilt;
  
  	RL_LOCK_ASSERT(sc);
  
  	rxfilt = CSR_READ_4(sc, RL_RXCFG);
  	rxfilt &= ~(RL_RXCFG_RX_ALLPHYS | RL_RXCFG_RX_BROAD |
  	    RL_RXCFG_RX_MULTI);
  	/* Always accept frames destined for this host. */
  	rxfilt |= RL_RXCFG_RX_INDIV;
  	/* Set capture broadcast bit to capture broadcast frames. */
  	if (ifp->if_flags & IFF_BROADCAST)
  		rxfilt |= RL_RXCFG_RX_BROAD;
  	if (ifp->if_flags & IFF_ALLMULTI || ifp->if_flags & IFF_PROMISC) {
  		rxfilt |= RL_RXCFG_RX_MULTI;
  		if (ifp->if_flags & IFF_PROMISC)
  			rxfilt |= RL_RXCFG_RX_ALLPHYS;
  		hashes[0] = 0xFFFFFFFF;
  		hashes[1] = 0xFFFFFFFF;
  	} else {
  		/* Now program new ones. */
  		if_maddr_rlock(ifp);
  		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));
  		}
  		if_maddr_runlock(ifp);
  		if (hashes[0] != 0 || hashes[1] != 0)
  			rxfilt |= RL_RXCFG_RX_MULTI;
  	}
  
  	CSR_WRITE_4(sc, RL_MAR0, hashes[0]);
  	CSR_WRITE_4(sc, RL_MAR4, hashes[1]);
  	CSR_WRITE_4(sc, RL_RXCFG, rxfilt);
  }
  
  static void
  rl_reset(struct rl_softc *sc)
  {
  	register int		i;
  
  	RL_LOCK_ASSERT(sc);
  
  	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.
   */
  static int
  rl_probe(device_t dev)
  {
  	const struct rl_type	*t;
  	uint16_t		devid, revid, vendor;
  	int			i;
  	
  	vendor = pci_get_vendor(dev);
  	devid = pci_get_device(dev);
  	revid = pci_get_revid(dev);
  
  	if (vendor == RT_VENDORID && devid == RT_DEVICEID_8139) {
  		if (revid == 0x20) {
  			/* 8139C+, let re(4) take care of this device. */
  			return (ENXIO);
  		}
  	}
  	t = rl_devs;
  	for (i = 0; i < nitems(rl_devs); i++, t++) {
  		if (vendor == t->rl_vid && devid == t->rl_did) {
  			device_set_desc(dev, t->rl_name);
  			return (BUS_PROBE_DEFAULT);
  		}
  	}
  
  	return (ENXIO);
  }
  
  struct rl_dmamap_arg {
  	bus_addr_t	rl_busaddr;
  };
  
  static void
  rl_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
  {
  	struct rl_dmamap_arg	*ctx;
  
  	if (error != 0)
  		return;
  
  	KASSERT(nsegs == 1, ("%s: %d segments returned!", __func__, nsegs));
  
          ctx = (struct rl_dmamap_arg *)arg;
          ctx->rl_busaddr = segs[0].ds_addr;
  }
  
  /*
   * 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 ifnet		*ifp;
  	struct rl_softc		*sc;
  	const struct rl_type	*t;
  	struct sysctl_ctx_list	*ctx;
  	struct sysctl_oid_list	*children;
  	int			error = 0, hwrev, i, phy, pmc, rid;
  	int			prefer_iomap, unit;
  	uint16_t		rl_did = 0;
  	char			tn[32];
  
  	sc = device_get_softc(dev);
  	unit = device_get_unit(dev);
  	sc->rl_dev = dev;
  
  	sc->rl_twister_enable = 0;
  	snprintf(tn, sizeof(tn), "dev.rl.%d.twister_enable", unit);
  	TUNABLE_INT_FETCH(tn, &sc->rl_twister_enable);
  	ctx = device_get_sysctl_ctx(sc->rl_dev);
  	children = SYSCTL_CHILDREN(device_get_sysctl_tree(sc->rl_dev));
  	SYSCTL_ADD_INT(ctx, children, OID_AUTO, "twister_enable", CTLFLAG_RD,
  	   &sc->rl_twister_enable, 0, "");
  
  	mtx_init(&sc->rl_mtx, device_get_nameunit(dev), MTX_NETWORK_LOCK,
  	    MTX_DEF);
  	callout_init_mtx(&sc->rl_stat_callout, &sc->rl_mtx, 0);
  
  	pci_enable_busmaster(dev);
  
  
  	/*
  	 * Map control/status registers.
  	 * 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.
  	 */
  	prefer_iomap = 1;
  	snprintf(tn, sizeof(tn), "dev.rl.%d.prefer_iomap", unit);
  	TUNABLE_INT_FETCH(tn, &prefer_iomap);
  	if (prefer_iomap) {
  		sc->rl_res_id = PCIR_BAR(0);
  		sc->rl_res_type = SYS_RES_IOPORT;
  		sc->rl_res = bus_alloc_resource_any(dev, sc->rl_res_type,
  		    &sc->rl_res_id, RF_ACTIVE);
  	}
  	if (prefer_iomap == 0 || sc->rl_res == NULL) {
  		sc->rl_res_id = PCIR_BAR(1);
  		sc->rl_res_type = SYS_RES_MEMORY;
  		sc->rl_res = bus_alloc_resource_any(dev, sc->rl_res_type,
  		    &sc->rl_res_id, RF_ACTIVE);
  	}
  	if (sc->rl_res == NULL) {
  		device_printf(dev, "couldn't map ports/memory\n");
  		error = ENXIO;
  		goto fail;
  	}
  
  #ifdef notdef
  	/*
  	 * Detect the Realtek 8139B. For some reason, this chip is very
  	 * unstable when left to autoselect the media
  	 * The best workaround is to set the device to the required
  	 * media type or to set it to the 10 Meg speed.
  	 */
  	if ((rman_get_end(sc->rl_res) - rman_get_start(sc->rl_res)) == 0xFF)
  		device_printf(dev,
  "Realtek 8139B detected. Warning, this may be unstable in autoselect mode\n");
  #endif
  
  	sc->rl_btag = rman_get_bustag(sc->rl_res);
  	sc->rl_bhandle = rman_get_bushandle(sc->rl_res);
  
  	/* Allocate interrupt */
  	rid = 0;
  	sc->rl_irq[0] = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
  	    RF_SHAREABLE | RF_ACTIVE);
  
  	if (sc->rl_irq[0] == NULL) {
  		device_printf(dev, "couldn't map interrupt\n");
  		error = ENXIO;
  		goto fail;
  	}
  
  	sc->rl_cfg0 = RL_8139_CFG0;
  	sc->rl_cfg1 = RL_8139_CFG1;
  	sc->rl_cfg2 = 0;
  	sc->rl_cfg3 = RL_8139_CFG3;
  	sc->rl_cfg4 = RL_8139_CFG4;
  	sc->rl_cfg5 = RL_8139_CFG5;
  
  	/*
  	 * Reset the adapter. Only take the lock here as it's needed in
  	 * order to call rl_reset().
  	 */
  	RL_LOCK(sc);
  	rl_reset(sc);
  	RL_UNLOCK(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, (uint8_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, (uint8_t *)&rl_did, RL_EE_PCI_DID, 1, 0);
  
  	t = rl_devs;
  	sc->rl_type = 0;
  	while(t->rl_name != NULL) {
  		if (rl_did == t->rl_did) {
  			sc->rl_type = t->rl_basetype;
  			break;
  		}
  		t++;
  	}
  
  	if (sc->rl_type == 0) {
  		device_printf(dev, "unknown device ID: %x assuming 8139\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);
  	}
  
  	if ((error = rl_dma_alloc(sc)) != 0)
  		goto fail;
  
  	ifp = sc->rl_ifp = if_alloc(IFT_ETHER);
  	if (ifp == NULL) {
  		device_printf(dev, "can not if_alloc()\n");
  		error = ENOSPC;
  		goto fail;
  	}
  
  #define	RL_PHYAD_INTERNAL	0
  
  	/* Do MII setup */
  	phy = MII_PHY_ANY;
  	if (sc->rl_type == RL_8139)
  		phy = RL_PHYAD_INTERNAL;
  	error = mii_attach(dev, &sc->rl_miibus, ifp, rl_ifmedia_upd,
  	    rl_ifmedia_sts, BMSR_DEFCAPMASK, phy, MII_OFFSET_ANY, 0);
  	if (error != 0) {
  		device_printf(dev, "attaching PHYs failed\n");
  		goto fail;
  	}
  
  	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_init = rl_init;
  	ifp->if_capabilities = IFCAP_VLAN_MTU;
  	/* Check WOL for RTL8139B or newer controllers. */
  	if (sc->rl_type == RL_8139 &&
  	    pci_find_cap(sc->rl_dev, PCIY_PMG, &pmc) == 0) {
  		hwrev = CSR_READ_4(sc, RL_TXCFG) & RL_TXCFG_HWREV;
  		switch (hwrev) {
  		case RL_HWREV_8139B:
  		case RL_HWREV_8130:
  		case RL_HWREV_8139C:
  		case RL_HWREV_8139D:
  		case RL_HWREV_8101:
  		case RL_HWREV_8100:
  			ifp->if_capabilities |= IFCAP_WOL;
  			/* Disable WOL. */
  			rl_clrwol(sc);
  			break;
  		default:
  			break;
  		}
  	}
  	ifp->if_capenable = ifp->if_capabilities;
  	ifp->if_capenable &= ~(IFCAP_WOL_UCAST | IFCAP_WOL_MCAST);
  #ifdef DEVICE_POLLING
  	ifp->if_capabilities |= IFCAP_POLLING;
  #endif
  	IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
  	ifp->if_snd.ifq_drv_maxlen = ifqmaxlen;
  	IFQ_SET_READY(&ifp->if_snd);
  
  	/*
  	 * Call MI attach routine.
  	 */
  	ether_ifattach(ifp, eaddr);
  
  	/* Hook interrupt last to avoid having to lock softc */
  	error = bus_setup_intr(dev, sc->rl_irq[0], INTR_TYPE_NET | INTR_MPSAFE,
  	    NULL, rl_intr, sc, &sc->rl_intrhand[0]);
  	if (error) {
  		device_printf(sc->rl_dev, "couldn't set up irq\n");
  		ether_ifdetach(ifp);
  	}
  
  fail:
  	if (error)
  		rl_detach(dev);
  
  	return (error);
  }
  
  /*
   * Shutdown hardware and free up resources. This can be called any
   * time after the mutex has been initialized. It is called in both
   * the error case in attach and the normal detach case so it needs
   * to be careful about only freeing resources that have actually been
   * allocated.
   */
  static int
  rl_detach(device_t dev)
  {
  	struct rl_softc		*sc;
  	struct ifnet		*ifp;
  
  	sc = device_get_softc(dev);
  	ifp = sc->rl_ifp;
  
  	KASSERT(mtx_initialized(&sc->rl_mtx), ("rl mutex not initialized"));
  
  #ifdef DEVICE_POLLING
  	if (ifp->if_capenable & IFCAP_POLLING)
  		ether_poll_deregister(ifp);
  #endif
  	/* These should only be active if attach succeeded */
  	if (device_is_attached(dev)) {
  		RL_LOCK(sc);
  		rl_stop(sc);
  		RL_UNLOCK(sc);
  		callout_drain(&sc->rl_stat_callout);
  		ether_ifdetach(ifp);
  	}
  #if 0
  	sc->suspended = 1;
  #endif
  	if (sc->rl_miibus)
  		device_delete_child(dev, sc->rl_miibus);
  	bus_generic_detach(dev);
  
  	if (sc->rl_intrhand[0])
  		bus_teardown_intr(dev, sc->rl_irq[0], sc->rl_intrhand[0]);
  	if (sc->rl_irq[0])
  		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->rl_irq[0]);
  	if (sc->rl_res)
  		bus_release_resource(dev, sc->rl_res_type, sc->rl_res_id,
  		    sc->rl_res);
  
  	if (ifp)
  		if_free(ifp);
  
  	rl_dma_free(sc);
  
  	mtx_destroy(&sc->rl_mtx);
  
  	return (0);
  }
  
  static int
  rl_dma_alloc(struct rl_softc *sc)
  {
  	struct rl_dmamap_arg	ctx;
  	int			error, i;
  
  	/*
  	 * Allocate the parent bus DMA tag appropriate for PCI.
  	 */
  	error = bus_dma_tag_create(bus_get_dma_tag(sc->rl_dev),	/* parent */
  	    1, 0,			/* alignment, boundary */
  	    BUS_SPACE_MAXADDR_32BIT,	/* lowaddr */
  	    BUS_SPACE_MAXADDR,		/* highaddr */
  	    NULL, NULL,			/* filter, filterarg */
  	    BUS_SPACE_MAXSIZE_32BIT, 0,	/* maxsize, nsegments */
  	    BUS_SPACE_MAXSIZE_32BIT,	/* maxsegsize */
  	    0,				/* flags */
  	    NULL, NULL,			/* lockfunc, lockarg */
  	    &sc->rl_parent_tag);
  	if (error) {
                  device_printf(sc->rl_dev,
  		    "failed to create parent DMA tag.\n");
  		goto fail;
  	}
  	/* Create DMA tag for Rx memory block. */
  	error = bus_dma_tag_create(sc->rl_parent_tag,	/* parent */
  	    RL_RX_8139_BUF_ALIGN, 0,	/* alignment, boundary */
  	    BUS_SPACE_MAXADDR,		/* lowaddr */
  	    BUS_SPACE_MAXADDR,		/* highaddr */
  	    NULL, NULL,			/* filter, filterarg */
  	    RL_RXBUFLEN + RL_RX_8139_BUF_GUARD_SZ, 1,	/* maxsize,nsegments */
  	    RL_RXBUFLEN + RL_RX_8139_BUF_GUARD_SZ,	/* maxsegsize */
  	    0,				/* flags */
  	    NULL, NULL,			/* lockfunc, lockarg */
  	    &sc->rl_cdata.rl_rx_tag);
  	if (error) {
                  device_printf(sc->rl_dev,
  		    "failed to create Rx memory block DMA tag.\n");
  		goto fail;
  	}
  	/* Create DMA tag for Tx buffer. */
  	error = bus_dma_tag_create(sc->rl_parent_tag,	/* parent */
  	    RL_TX_8139_BUF_ALIGN, 0,	/* alignment, boundary */
  	    BUS_SPACE_MAXADDR,		/* lowaddr */
  	    BUS_SPACE_MAXADDR,		/* highaddr */
  	    NULL, NULL,			/* filter, filterarg */
  	    MCLBYTES, 1,		/* maxsize, nsegments */
  	    MCLBYTES,			/* maxsegsize */
  	    0,				/* flags */
  	    NULL, NULL,			/* lockfunc, lockarg */
  	    &sc->rl_cdata.rl_tx_tag);
  	if (error) {
                  device_printf(sc->rl_dev, "failed to create Tx DMA tag.\n");
  		goto fail;
  	}
  
  	/*
  	 * Allocate DMA'able memory and load DMA map for Rx memory block.
  	 */
  	error = bus_dmamem_alloc(sc->rl_cdata.rl_rx_tag,
  	    (void **)&sc->rl_cdata.rl_rx_buf, BUS_DMA_WAITOK |
  	    BUS_DMA_COHERENT | BUS_DMA_ZERO, &sc->rl_cdata.rl_rx_dmamap);
  	if (error != 0) {
  		device_printf(sc->rl_dev,
  		    "failed to allocate Rx DMA memory block.\n");
  		goto fail;
  	}
  	ctx.rl_busaddr = 0;
  	error = bus_dmamap_load(sc->rl_cdata.rl_rx_tag,
  	    sc->rl_cdata.rl_rx_dmamap, sc->rl_cdata.rl_rx_buf,
  	    RL_RXBUFLEN + RL_RX_8139_BUF_GUARD_SZ, rl_dmamap_cb, &ctx,
  	    BUS_DMA_NOWAIT);
  	if (error != 0 || ctx.rl_busaddr == 0) {
  		device_printf(sc->rl_dev,
  		    "could not load Rx DMA memory block.\n");
  		goto fail;
  	}
  	sc->rl_cdata.rl_rx_buf_paddr = ctx.rl_busaddr;
  
  	/* Create DMA maps for Tx buffers. */
  	for (i = 0; i < RL_TX_LIST_CNT; i++) {
  		sc->rl_cdata.rl_tx_chain[i] = NULL;
  		sc->rl_cdata.rl_tx_dmamap[i] = NULL;
  		error = bus_dmamap_create(sc->rl_cdata.rl_tx_tag, 0,
  		    &sc->rl_cdata.rl_tx_dmamap[i]);
  		if (error != 0) {
  			device_printf(sc->rl_dev,
  			    "could not create Tx dmamap.\n");
  			goto fail;
  		}
  	}
  
  	/* Leave a few bytes before the start of the RX ring buffer. */
  	sc->rl_cdata.rl_rx_buf_ptr = sc->rl_cdata.rl_rx_buf;
  	sc->rl_cdata.rl_rx_buf += RL_RX_8139_BUF_RESERVE;
  
  fail:
  	return (error);
  }
  
  static void
  rl_dma_free(struct rl_softc *sc)
  {
  	int			i;
  
  	/* Rx memory block. */
  	if (sc->rl_cdata.rl_rx_tag != NULL) {
  		if (sc->rl_cdata.rl_rx_buf_paddr != 0)
  			bus_dmamap_unload(sc->rl_cdata.rl_rx_tag,
  			    sc->rl_cdata.rl_rx_dmamap);
  		if (sc->rl_cdata.rl_rx_buf_ptr != NULL)
  			bus_dmamem_free(sc->rl_cdata.rl_rx_tag,
  			    sc->rl_cdata.rl_rx_buf_ptr,
  			    sc->rl_cdata.rl_rx_dmamap);
  		sc->rl_cdata.rl_rx_buf_ptr = NULL;
  		sc->rl_cdata.rl_rx_buf = NULL;
  		sc->rl_cdata.rl_rx_buf_paddr = 0;
  		bus_dma_tag_destroy(sc->rl_cdata.rl_rx_tag);
  		sc->rl_cdata.rl_tx_tag = NULL;
  	}
  
  	/* Tx buffers. */
  	if (sc->rl_cdata.rl_tx_tag != NULL) {
  		for (i = 0; i < RL_TX_LIST_CNT; i++) {
  			if (sc->rl_cdata.rl_tx_dmamap[i] != NULL) {
  				bus_dmamap_destroy(
  				    sc->rl_cdata.rl_tx_tag,
  				    sc->rl_cdata.rl_tx_dmamap[i]);
  				sc->rl_cdata.rl_tx_dmamap[i] = NULL;
  			}
  		}
  		bus_dma_tag_destroy(sc->rl_cdata.rl_tx_tag);
  		sc->rl_cdata.rl_tx_tag = NULL;
  	}
  
  	if (sc->rl_parent_tag != NULL) {
  		bus_dma_tag_destroy(sc->rl_parent_tag);
  		sc->rl_parent_tag = NULL;
  	}
  }
  
  /*
   * Initialize the transmit descriptors.
   */
  static int
  rl_list_tx_init(struct rl_softc *sc)
  {
  	struct rl_chain_data	*cd;
  	int			i;
  
  	RL_LOCK_ASSERT(sc);
  
  	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;
  
  	return (0);
  }
  
  static int
  rl_list_rx_init(struct rl_softc *sc)
  {
  
  	RL_LOCK_ASSERT(sc);
  
  	bzero(sc->rl_cdata.rl_rx_buf_ptr,
  	    RL_RXBUFLEN + RL_RX_8139_BUF_GUARD_SZ);
  	bus_dmamap_sync(sc->rl_cdata.rl_tx_tag, sc->rl_cdata.rl_rx_dmamap,
  	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
  
  	return (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 pass RL_ETHER_ALIGN (2 bytes)
   * as the offset argument to m_devget().
   */
  static int
  rl_rxeof(struct rl_softc *sc)
  {
  	struct mbuf		*m;
  	struct ifnet		*ifp = sc->rl_ifp;
  	uint8_t			*rxbufpos;
  	int			total_len = 0;
  	int			wrap = 0;
  	int			rx_npkts = 0;
  	uint32_t		rxstat;
  	uint16_t		cur_rx;
  	uint16_t		limit;
  	uint16_t		max_bytes, rx_bytes = 0;
  
  	RL_LOCK_ASSERT(sc);
  
  	bus_dmamap_sync(sc->rl_cdata.rl_rx_tag, sc->rl_cdata.rl_rx_dmamap,
  	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
  
  	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;
  
  	while((CSR_READ_1(sc, RL_COMMAND) & RL_CMD_EMPTY_RXBUF) == 0) {
  #ifdef DEVICE_POLLING
  		if (ifp->if_capenable & IFCAP_POLLING) {
  			if (sc->rxcycles <= 0)
  				break;
  			sc->rxcycles--;
  		}
  #endif
  		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.
  		 */
  		total_len = rxstat >> 16;
  		if (total_len == RL_RXSTAT_UNFINISHED)
  			break;
  
  		if (!(rxstat & RL_RXSTAT_RXOK) ||
  		    total_len < ETHER_MIN_LEN ||
  		    total_len > ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN) {
  			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
  			ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
  			rl_init_locked(sc);
  			return (rx_npkts);
  		}
  
  		/* No errors; receive the packet. */
  		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) {
  			m = m_devget(rxbufpos, total_len, RL_ETHER_ALIGN, ifp,
  			    NULL);
  			if (m != NULL)
  				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, total_len, RL_ETHER_ALIGN, ifp,
  			    NULL);
  			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) {
  			if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
  			continue;
  		}
  
  		if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
  		RL_UNLOCK(sc);
  		(*ifp->if_input)(ifp, m);
  		RL_LOCK(sc);
  		rx_npkts++;
  	}
  
  	/* No need to sync Rx memory block as we didn't modify it. */
  	return (rx_npkts);
  }
  
  /*
   * 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 = sc->rl_ifp;
  	uint32_t		txstat;
  
  	RL_LOCK_ASSERT(sc);
  
  	/*
  	 * 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)))
  			break;
  
  		if_inc_counter(ifp, IFCOUNTER_COLLISIONS, (txstat & RL_TXSTAT_COLLCNT) >> 24);
  
  		bus_dmamap_sync(sc->rl_cdata.rl_tx_tag, RL_LAST_DMAMAP(sc),
  		    BUS_DMASYNC_POSTWRITE);
  		bus_dmamap_unload(sc->rl_cdata.rl_tx_tag, RL_LAST_DMAMAP(sc));
  		m_freem(RL_LAST_TXMBUF(sc));
  		RL_LAST_TXMBUF(sc) = NULL;
  		/*
  		 * If there was a transmit underrun, bump the TX threshold.
  		 * Make sure not to overflow the 63 * 32byte we can address
  		 * with the 6 available bit.
  		 */
  		if ((txstat & RL_TXSTAT_TX_UNDERRUN) &&
  		    (sc->rl_txthresh < 2016))
  			sc->rl_txthresh += 32;
  		if (txstat & RL_TXSTAT_TX_OK)
  			if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
  		else {
  			int			oldthresh;
  			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
  			if ((txstat & RL_TXSTAT_TXABRT) ||
  			    (txstat & RL_TXSTAT_OUTOFWIN))
  				CSR_WRITE_4(sc, RL_TXCFG, RL_TXCFG_CONFIG);
  			oldthresh = sc->rl_txthresh;
  			/* error recovery */
  			ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
  			rl_init_locked(sc);
  			/* restore original threshold */
  			sc->rl_txthresh = oldthresh;
  			return;
  		}
  		RL_INC(sc->rl_cdata.last_tx);
  		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
  	} while (sc->rl_cdata.last_tx != sc->rl_cdata.cur_tx);
  
  	if (RL_LAST_TXMBUF(sc) == NULL)
  		sc->rl_watchdog_timer = 0;
  }
  
  static void
  rl_twister_update(struct rl_softc *sc)
  {
  	uint16_t linktest;
  	/*
  	 * Table provided by RealTek (Kinston <shangh@realtek.com.tw>) for
  	 * Linux driver.  Values undocumented otherwise.
  	 */
  	static const uint32_t param[4][4] = {
  		{0xcb39de43, 0xcb39ce43, 0xfb38de03, 0xcb38de43},
  		{0xcb39de43, 0xcb39ce43, 0xcb39ce83, 0xcb39ce83},
  		{0xcb39de43, 0xcb39ce43, 0xcb39ce83, 0xcb39ce83},
  		{0xbb39de43, 0xbb39ce43, 0xbb39ce83, 0xbb39ce83}
  	};
  
  	/*
  	 * Tune the so-called twister registers of the RTL8139.  These
  	 * are used to compensate for impedance mismatches.  The
  	 * method for tuning these registers is undocumented and the
  	 * following procedure is collected from public sources.
  	 */
  	switch (sc->rl_twister)
  	{
  	case CHK_LINK:
  		/*
  		 * If we have a sufficient link, then we can proceed in
  		 * the state machine to the next stage.  If not, then
  		 * disable further tuning after writing sane defaults.
  		 */
  		if (CSR_READ_2(sc, RL_CSCFG) & RL_CSCFG_LINK_OK) {
  			CSR_WRITE_2(sc, RL_CSCFG, RL_CSCFG_LINK_DOWN_OFF_CMD);
  			sc->rl_twister = FIND_ROW;
  		} else {
  			CSR_WRITE_2(sc, RL_CSCFG, RL_CSCFG_LINK_DOWN_CMD);
  			CSR_WRITE_4(sc, RL_NWAYTST, RL_NWAYTST_CBL_TEST);
  			CSR_WRITE_4(sc, RL_PARA78, RL_PARA78_DEF);
  			CSR_WRITE_4(sc, RL_PARA7C, RL_PARA7C_DEF);
  			sc->rl_twister = DONE;
  		}
  		break;
  	case FIND_ROW:
  		/*
  		 * Read how long it took to see the echo to find the tuning
  		 * row to use.
  		 */
  		linktest = CSR_READ_2(sc, RL_CSCFG) & RL_CSCFG_STATUS;
  		if (linktest == RL_CSCFG_ROW3)
  			sc->rl_twist_row = 3;
  		else if (linktest == RL_CSCFG_ROW2)
  			sc->rl_twist_row = 2;
  		else if (linktest == RL_CSCFG_ROW1)
  			sc->rl_twist_row = 1;
  		else
  			sc->rl_twist_row = 0;
  		sc->rl_twist_col = 0;
  		sc->rl_twister = SET_PARAM;
  		break;
  	case SET_PARAM:
  		if (sc->rl_twist_col == 0)
  			CSR_WRITE_4(sc, RL_NWAYTST, RL_NWAYTST_RESET);
  		CSR_WRITE_4(sc, RL_PARA7C,
  		    param[sc->rl_twist_row][sc->rl_twist_col]);
  		if (++sc->rl_twist_col == 4) {
  			if (sc->rl_twist_row == 3)
  				sc->rl_twister = RECHK_LONG;
  			else
  				sc->rl_twister = DONE;
  		}
  		break;
  	case RECHK_LONG:
  		/*
  		 * For long cables, we have to double check to make sure we
  		 * don't mistune.
  		 */
  		linktest = CSR_READ_2(sc, RL_CSCFG) & RL_CSCFG_STATUS;
  		if (linktest == RL_CSCFG_ROW3)
  			sc->rl_twister = DONE;
  		else {
  			CSR_WRITE_4(sc, RL_PARA7C, RL_PARA7C_RETUNE);
  			sc->rl_twister = RETUNE;
  		}
  		break;
  	case RETUNE:
  		/* Retune for a shorter cable (try column 2) */
  		CSR_WRITE_4(sc, RL_NWAYTST, RL_NWAYTST_CBL_TEST);
  		CSR_WRITE_4(sc, RL_PARA78, RL_PARA78_DEF);
  		CSR_WRITE_4(sc, RL_PARA7C, RL_PARA7C_DEF);
  		CSR_WRITE_4(sc, RL_NWAYTST, RL_NWAYTST_RESET);
  		sc->rl_twist_row--;
  		sc->rl_twist_col = 0;
  		sc->rl_twister = SET_PARAM;
  		break;
  
  	case DONE:
  		break;
  	}
  	
  }
  
  static void
  rl_tick(void *xsc)
  {
  	struct rl_softc		*sc = xsc;
  	struct mii_data		*mii;
  	int ticks;
  
  	RL_LOCK_ASSERT(sc);
  	/*
  	 * If we're doing the twister cable calibration, then we need to defer
  	 * watchdog timeouts.  This is a no-op in normal operations, but
  	 * can falsely trigger when the cable calibration takes a while and
  	 * there was traffic ready to go when rl was started.
  	 *
  	 * We don't defer mii_tick since that updates the mii status, which
  	 * helps the twister process, at least according to similar patches
  	 * for the Linux driver I found online while doing the fixes.  Worst
  	 * case is a few extra mii reads during calibration.
  	 */
  	mii = device_get_softc(sc->rl_miibus);
  	mii_tick(mii);
  	if ((sc->rl_flags & RL_FLAG_LINK) == 0)
  		rl_miibus_statchg(sc->rl_dev);
  	if (sc->rl_twister_enable) {
  		if (sc->rl_twister == DONE)
  			rl_watchdog(sc);
  		else
  			rl_twister_update(sc);
  		if (sc->rl_twister == DONE)
  			ticks = hz;
  		else
  			ticks = hz / 10;
  	} else {
  		rl_watchdog(sc);
  		ticks = hz;
  	}
  
  	callout_reset(&sc->rl_stat_callout, ticks, rl_tick, sc);
  }
  
  #ifdef DEVICE_POLLING
  static int
  rl_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
  {
  	struct rl_softc *sc = ifp->if_softc;
  	int rx_npkts = 0;
  
  	RL_LOCK(sc);
  	if (ifp->if_drv_flags & IFF_DRV_RUNNING)
  		rx_npkts = rl_poll_locked(ifp, cmd, count);
  	RL_UNLOCK(sc);
  	return (rx_npkts);
  }
  
  static int
  rl_poll_locked(struct ifnet *ifp, enum poll_cmd cmd, int count)
  {
  	struct rl_softc *sc = ifp->if_softc;
  	int rx_npkts;
  
  	RL_LOCK_ASSERT(sc);
  
  	sc->rxcycles = count;
  	rx_npkts = rl_rxeof(sc);
  	rl_txeof(sc);
  
  	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
  		rl_start_locked(ifp);
  
  	if (cmd == POLL_AND_CHECK_STATUS) {
  		uint16_t	status;
  
  		/* We should also check the status register. */
  		status = CSR_READ_2(sc, RL_ISR);
  		if (status == 0xffff)
  			return (rx_npkts);
  		if (status != 0)
  			CSR_WRITE_2(sc, RL_ISR, status);
  
  		/* XXX We should check behaviour on receiver stalls. */
  
  		if (status & RL_ISR_SYSTEM_ERR) {
  			ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
  			rl_init_locked(sc);
  		}
  	}
  	return (rx_npkts);
  }
  #endif /* DEVICE_POLLING */
  
  static void
  rl_intr(void *arg)
  {
  	struct rl_softc		*sc = arg;
  	struct ifnet		*ifp = sc->rl_ifp;
  	uint16_t		status;
  	int			count;
  
  	RL_LOCK(sc);
  
  	if (sc->suspended)
  		goto done_locked;
  
  #ifdef DEVICE_POLLING
  	if  (ifp->if_capenable & IFCAP_POLLING)
  		goto done_locked;
  #endif
  
  	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
  		goto done_locked2;
  	status = CSR_READ_2(sc, RL_ISR);
  	if (status == 0xffff || (status & RL_INTRS) == 0)
  		goto done_locked;
  	/*
  	 * Ours, disable further interrupts.
  	 */
  	CSR_WRITE_2(sc, RL_IMR, 0);
  	for (count = 16; count > 0; count--) {
  		CSR_WRITE_2(sc, RL_ISR, status);
  		if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
  			if (status & (RL_ISR_RX_OK | RL_ISR_RX_ERR))
  				rl_rxeof(sc);
  			if (status & (RL_ISR_TX_OK | RL_ISR_TX_ERR))
  				rl_txeof(sc);
  			if (status & RL_ISR_SYSTEM_ERR) {
  				ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
  				rl_init_locked(sc);
  				RL_UNLOCK(sc);
  				return;
  			}
  		}
  		status = CSR_READ_2(sc, RL_ISR);
  		/* If the card has gone away, the read returns 0xffff. */
  		if (status == 0xffff || (status & RL_INTRS) == 0)
  			break;
  	}
  
  	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
  		rl_start_locked(ifp);
  
  done_locked2:
  	if (ifp->if_drv_flags & IFF_DRV_RUNNING)
  		CSR_WRITE_2(sc, RL_IMR, RL_INTRS);
  done_locked:
  	RL_UNLOCK(sc);
  }
  
  /*
   * 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;
  	bus_dma_segment_t	txsegs[1];
  	int			error, nsegs, padlen;
  
  	RL_LOCK_ASSERT(sc);
  
  	m = *m_head;
  	padlen = 0;
  	/*
  	 * Hardware doesn't auto-pad, so we have to make sure
  	 * pad short frames out to the minimum frame length.
  	 */
  	if (m->m_pkthdr.len < RL_MIN_FRAMELEN)
  		padlen = RL_MIN_FRAMELEN - m->m_pkthdr.len;
  	/*
  	 * 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.
  	 */
  	if (m->m_next != NULL || (mtod(m, uintptr_t) & 3) != 0 ||
  	    (padlen > 0 && M_TRAILINGSPACE(m) < padlen)) {
  		m = m_defrag(*m_head, M_NOWAIT);
  		if (m == NULL) {
  			m_freem(*m_head);
  			*m_head = NULL;
  			return (ENOMEM);
  		}
  	}
  	*m_head = m;
  
  	if (padlen > 0) {
  		/*
  		 * Make security-conscious people happy: zero out the
  		 * bytes in the pad area, since we don't know what
  		 * this mbuf cluster buffer's previous user might
  		 * have left in it.
  		 */
  		bzero(mtod(m, char *) + m->m_pkthdr.len, padlen);
  		m->m_pkthdr.len += padlen;
  		m->m_len = m->m_pkthdr.len;
  	}
  
  	error = bus_dmamap_load_mbuf_sg(sc->rl_cdata.rl_tx_tag,
  	    RL_CUR_DMAMAP(sc), m, txsegs, &nsegs, 0);
  	if (error != 0)
  		return (error);
  	if (nsegs == 0) {
  		m_freem(*m_head);
  		*m_head = NULL;
  		return (EIO);
  	}
  
  	RL_CUR_TXMBUF(sc) = m;
  	bus_dmamap_sync(sc->rl_cdata.rl_tx_tag, RL_CUR_DMAMAP(sc),
  	    BUS_DMASYNC_PREWRITE);
  	CSR_WRITE_4(sc, RL_CUR_TXADDR(sc), RL_ADDR_LO(txsegs[0].ds_addr));
  
  	return (0);
  }
  
  /*
   * Main transmit routine.
   */
  static void
  rl_start(struct ifnet *ifp)
  {
  	struct rl_softc		*sc = ifp->if_softc;
  
  	RL_LOCK(sc);
  	rl_start_locked(ifp);
  	RL_UNLOCK(sc);
  }
  
  static void
  rl_start_locked(struct ifnet *ifp)
  {
  	struct rl_softc		*sc = ifp->if_softc;
  	struct mbuf		*m_head = NULL;
  
  	RL_LOCK_ASSERT(sc);
  
  	if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
  	    IFF_DRV_RUNNING || (sc->rl_flags & RL_FLAG_LINK) == 0)
  		return;
  
  	while (RL_CUR_TXMBUF(sc) == NULL) {
  
  		IFQ_DRV_DEQUEUE(&ifp->if_snd, m_head);
  
  		if (m_head == NULL)
  			break;
  
  		if (rl_encap(sc, &m_head)) {
  			if (m_head == NULL)
  				break;
  			IFQ_DRV_PREPEND(&ifp->if_snd, m_head);
  			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
  			break;
  		}
  
  		/* Pass a copy of this mbuf chain to the bpf subsystem. */
  		BPF_MTAP(ifp, RL_CUR_TXMBUF(sc));
  
  		/* Transmit the frame. */
  		CSR_WRITE_4(sc, RL_CUR_TXSTAT(sc),
  		    RL_TXTHRESH(sc->rl_txthresh) |
  		    RL_CUR_TXMBUF(sc)->m_pkthdr.len);
  
  		RL_INC(sc->rl_cdata.cur_tx);
  
  		/* Set a timeout in case the chip goes out to lunch. */
  		sc->rl_watchdog_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)
  		ifp->if_drv_flags |= IFF_DRV_OACTIVE;
  }
  
  static void
  rl_init(void *xsc)
  {
  	struct rl_softc		*sc = xsc;
  
  	RL_LOCK(sc);
  	rl_init_locked(sc);
  	RL_UNLOCK(sc);
  }
  
  static void
  rl_init_locked(struct rl_softc *sc)
  {
  	struct ifnet		*ifp = sc->rl_ifp;
  	struct mii_data		*mii;
  	uint32_t		eaddr[2];
  
  	RL_LOCK_ASSERT(sc);
  
  	mii = device_get_softc(sc->rl_miibus);
  
  	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
  		return;
  
  	/*
  	 * Cancel pending I/O and free all RX/TX buffers.
  	 */
  	rl_stop(sc);
  
  	rl_reset(sc);
  	if (sc->rl_twister_enable) {
  		/*
  		 * Reset twister register tuning state.  The twister
  		 * registers and their tuning are undocumented, but
  		 * are necessary to cope with bad links.  rl_twister =
  		 * DONE here will disable this entirely.
  		 */
  		sc->rl_twister = CHK_LINK;
  	}
  
  	/*
  	 * 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);
  	bzero(eaddr, sizeof(eaddr));
  	bcopy(IF_LLADDR(sc->rl_ifp), eaddr, ETHER_ADDR_LEN);
  	CSR_WRITE_STREAM_4(sc, RL_IDR0, eaddr[0]);
  	CSR_WRITE_STREAM_4(sc, RL_IDR4, eaddr[1]);
  	CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
  
  	/* Init the RX memory block pointer register. */
  	CSR_WRITE_4(sc, RL_RXADDR, sc->rl_cdata.rl_rx_buf_paddr +
  	    RL_RX_8139_BUF_RESERVE);
  	/* Init TX descriptors. */
  	rl_list_tx_init(sc);
  	/* Init Rx memory block. */
  	rl_list_rx_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 RX filter. */
  	rl_rxfilter(sc);
  
  #ifdef DEVICE_POLLING
  	/* Disable interrupts if we are polling. */
  	if (ifp->if_capenable & IFCAP_POLLING)
  		CSR_WRITE_2(sc, RL_IMR, 0);
  	else
  #endif
  	/* 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);
  
  	sc->rl_flags &= ~RL_FLAG_LINK;
  	mii_mediachg(mii);
  
  	CSR_WRITE_1(sc, sc->rl_cfg1, RL_CFG1_DRVLOAD|RL_CFG1_FULLDUPLEX);
  
  	ifp->if_drv_flags |= IFF_DRV_RUNNING;
  	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
  
  	callout_reset(&sc->rl_stat_callout, hz, rl_tick, sc);
  }
  
  /*
   * Set media options.
   */
  static int
  rl_ifmedia_upd(struct ifnet *ifp)
  {
  	struct rl_softc		*sc = ifp->if_softc;
  	struct mii_data		*mii;
  
  	mii = device_get_softc(sc->rl_miibus);
  
  	RL_LOCK(sc);
  	mii_mediachg(mii);
  	RL_UNLOCK(sc);
  
  	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;
  
  	mii = device_get_softc(sc->rl_miibus);
  
  	RL_LOCK(sc);
  	mii_pollstat(mii);
  	ifmr->ifm_active = mii->mii_media_active;
  	ifmr->ifm_status = mii->mii_media_status;
  	RL_UNLOCK(sc);
  }
  
  static int
  rl_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
  {
  	struct ifreq		*ifr = (struct ifreq *)data;
  	struct mii_data		*mii;
  	struct rl_softc		*sc = ifp->if_softc;
  	int			error = 0, mask;
  
  	switch (command) {
  	case SIOCSIFFLAGS:
  		RL_LOCK(sc);
  		if (ifp->if_flags & IFF_UP) {
  			if (ifp->if_drv_flags & IFF_DRV_RUNNING &&
  			    ((ifp->if_flags ^ sc->rl_if_flags) &
                              (IFF_PROMISC | IFF_ALLMULTI)))
  				rl_rxfilter(sc);
                          else
  				rl_init_locked(sc);
                  } else if (ifp->if_drv_flags & IFF_DRV_RUNNING)
  			rl_stop(sc);
  		sc->rl_if_flags = ifp->if_flags;
  		RL_UNLOCK(sc);
  		break;
  	case SIOCADDMULTI:
  	case SIOCDELMULTI:
  		RL_LOCK(sc);
  		rl_rxfilter(sc);
  		RL_UNLOCK(sc);
  		break;
  	case SIOCGIFMEDIA:
  	case SIOCSIFMEDIA:
  		mii = device_get_softc(sc->rl_miibus);
  		error = ifmedia_ioctl(ifp, ifr, &mii->mii_media, command);
  		break;
  	case SIOCSIFCAP:
  		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
  #ifdef DEVICE_POLLING
  		if (ifr->ifr_reqcap & IFCAP_POLLING &&
  		    !(ifp->if_capenable & IFCAP_POLLING)) {
  			error = ether_poll_register(rl_poll, ifp);
  			if (error)
  				return(error);
  			RL_LOCK(sc);
  			/* Disable interrupts */
  			CSR_WRITE_2(sc, RL_IMR, 0x0000);
  			ifp->if_capenable |= IFCAP_POLLING;
  			RL_UNLOCK(sc);
  			return (error);
  			
  		}
  		if (!(ifr->ifr_reqcap & IFCAP_POLLING) &&
  		    ifp->if_capenable & IFCAP_POLLING) {
  			error = ether_poll_deregister(ifp);
  			/* Enable interrupts. */
  			RL_LOCK(sc);
  			CSR_WRITE_2(sc, RL_IMR, RL_INTRS);
  			ifp->if_capenable &= ~IFCAP_POLLING;
  			RL_UNLOCK(sc);
  			return (error);
  		}
  #endif /* DEVICE_POLLING */
  		if ((mask & IFCAP_WOL) != 0 &&
  		    (ifp->if_capabilities & IFCAP_WOL) != 0) {
  			if ((mask & IFCAP_WOL_UCAST) != 0)
  				ifp->if_capenable ^= IFCAP_WOL_UCAST;
  			if ((mask & IFCAP_WOL_MCAST) != 0)
  				ifp->if_capenable ^= IFCAP_WOL_MCAST;
  			if ((mask & IFCAP_WOL_MAGIC) != 0)
  				ifp->if_capenable ^= IFCAP_WOL_MAGIC;
  		}
  		break;
  	default:
  		error = ether_ioctl(ifp, command, data);
  		break;
  	}
  
  	return (error);
  }
  
  static void
  rl_watchdog(struct rl_softc *sc)
  {
  
  	RL_LOCK_ASSERT(sc);
  
  	if (sc->rl_watchdog_timer == 0 || --sc->rl_watchdog_timer >0)
  		return;
  
  	device_printf(sc->rl_dev, "watchdog timeout\n");
  	if_inc_counter(sc->rl_ifp, IFCOUNTER_OERRORS, 1);
  
  	rl_txeof(sc);
  	rl_rxeof(sc);
  	sc->rl_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
  	rl_init_locked(sc);
  }
  
  /*
   * Stop the adapter and free any mbufs allocated to the
   * RX and TX lists.
   */
  static void
  rl_stop(struct rl_softc *sc)
  {
  	register int		i;
  	struct ifnet		*ifp = sc->rl_ifp;
  
  	RL_LOCK_ASSERT(sc);
  
  	sc->rl_watchdog_timer = 0;
  	callout_stop(&sc->rl_stat_callout);
  	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
  	sc->rl_flags &= ~RL_FLAG_LINK;
  
  	CSR_WRITE_1(sc, RL_COMMAND, 0x00);
  	CSR_WRITE_2(sc, RL_IMR, 0x0000);
  	for (i = 0; i < RL_TIMEOUT; i++) {
  		DELAY(10);
  		if ((CSR_READ_1(sc, RL_COMMAND) &
  		    (RL_CMD_RX_ENB | RL_CMD_TX_ENB)) == 0)
  			break;
  	}
  	if (i == RL_TIMEOUT)
  		device_printf(sc->rl_dev, "Unable to stop Tx/Rx MAC\n");
  
  	/*
  	 * 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_sync(sc->rl_cdata.rl_tx_tag,
  			    sc->rl_cdata.rl_tx_dmamap[i],
  			    BUS_DMASYNC_POSTWRITE);
  			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);
  		}
  	}
  }
  
  /*
   * 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;
  
  	sc = device_get_softc(dev);
  
  	RL_LOCK(sc);
  	rl_stop(sc);
  	rl_setwol(sc);
  	sc->suspended = 1;
  	RL_UNLOCK(sc);
  
  	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;
  	struct ifnet		*ifp;
  	int			pmc;
  	uint16_t		pmstat;
  
  	sc = device_get_softc(dev);
  	ifp = sc->rl_ifp;
  
  	RL_LOCK(sc);
  
  	if ((ifp->if_capabilities & IFCAP_WOL) != 0 &&
  	    pci_find_cap(sc->rl_dev, PCIY_PMG, &pmc) == 0) {
  		/* Disable PME and clear PME status. */
  		pmstat = pci_read_config(sc->rl_dev,
  		    pmc + PCIR_POWER_STATUS, 2);
  		if ((pmstat & PCIM_PSTAT_PMEENABLE) != 0) {
  			pmstat &= ~PCIM_PSTAT_PMEENABLE;
  			pci_write_config(sc->rl_dev,
  			    pmc + PCIR_POWER_STATUS, pmstat, 2);
  		}
  		/*
  		 * Clear WOL matching such that normal Rx filtering
  		 * wouldn't interfere with WOL patterns.
  		 */
  		rl_clrwol(sc);
  	}
  
  	/* reinitialize interface if necessary */
  	if (ifp->if_flags & IFF_UP)
  		rl_init_locked(sc);
  
  	sc->suspended = 0;
  
  	RL_UNLOCK(sc);
  
  	return (0);
  }
  
  /*
   * Stop all chip I/O so that the kernel's probe routines don't
   * get confused by errant DMAs when rebooting.
   */
  static int
  rl_shutdown(device_t dev)
  {
  	struct rl_softc		*sc;
  
  	sc = device_get_softc(dev);
  
  	RL_LOCK(sc);
  	rl_stop(sc);
  	/*
  	 * Mark interface as down since otherwise we will panic if
  	 * interrupt comes in later on, which can happen in some
  	 * cases.
  	 */
  	sc->rl_ifp->if_flags &= ~IFF_UP;
  	rl_setwol(sc);
  	RL_UNLOCK(sc);
  
  	return (0);
  }
  
  static void
  rl_setwol(struct rl_softc *sc)
  {
  	struct ifnet		*ifp;
  	int			pmc;
  	uint16_t		pmstat;
  	uint8_t			v;
  
  	RL_LOCK_ASSERT(sc);
  
  	ifp = sc->rl_ifp;
  	if ((ifp->if_capabilities & IFCAP_WOL) == 0)
  		return;
  	if (pci_find_cap(sc->rl_dev, PCIY_PMG, &pmc) != 0)
  		return;
  
  	/* Enable config register write. */
  	CSR_WRITE_1(sc, RL_EECMD, RL_EE_MODE);
  
  	/* Enable PME. */
  	v = CSR_READ_1(sc, sc->rl_cfg1);
  	v &= ~RL_CFG1_PME;
  	if ((ifp->if_capenable & IFCAP_WOL) != 0)
  		v |= RL_CFG1_PME;
  	CSR_WRITE_1(sc, sc->rl_cfg1, v);
  
  	v = CSR_READ_1(sc, sc->rl_cfg3);
  	v &= ~(RL_CFG3_WOL_LINK | RL_CFG3_WOL_MAGIC);
  	if ((ifp->if_capenable & IFCAP_WOL_MAGIC) != 0)
  		v |= RL_CFG3_WOL_MAGIC;
  	CSR_WRITE_1(sc, sc->rl_cfg3, v);
  
  	v = CSR_READ_1(sc, sc->rl_cfg5);
  	v &= ~(RL_CFG5_WOL_BCAST | RL_CFG5_WOL_MCAST | RL_CFG5_WOL_UCAST);
  	v &= ~RL_CFG5_WOL_LANWAKE;
  	if ((ifp->if_capenable & IFCAP_WOL_UCAST) != 0)
  		v |= RL_CFG5_WOL_UCAST;
  	if ((ifp->if_capenable & IFCAP_WOL_MCAST) != 0)
  		v |= RL_CFG5_WOL_MCAST | RL_CFG5_WOL_BCAST;
  	if ((ifp->if_capenable & IFCAP_WOL) != 0)
  		v |= RL_CFG5_WOL_LANWAKE;
  	CSR_WRITE_1(sc, sc->rl_cfg5, v);
  
  	/* Config register write done. */
  	CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
  
  	/* Request PME if WOL is requested. */
  	pmstat = pci_read_config(sc->rl_dev, pmc + PCIR_POWER_STATUS, 2);
  	pmstat &= ~(PCIM_PSTAT_PME | PCIM_PSTAT_PMEENABLE);
  	if ((ifp->if_capenable & IFCAP_WOL) != 0)
  		pmstat |= PCIM_PSTAT_PME | PCIM_PSTAT_PMEENABLE;
  	pci_write_config(sc->rl_dev, pmc + PCIR_POWER_STATUS, pmstat, 2);
  }
  
  static void
  rl_clrwol(struct rl_softc *sc)
  {
  	struct ifnet		*ifp;
  	uint8_t			v;
  
  	ifp = sc->rl_ifp;
  	if ((ifp->if_capabilities & IFCAP_WOL) == 0)
  		return;
  
  	/* Enable config register write. */
  	CSR_WRITE_1(sc, RL_EECMD, RL_EE_MODE);
  
  	v = CSR_READ_1(sc, sc->rl_cfg3);
  	v &= ~(RL_CFG3_WOL_LINK | RL_CFG3_WOL_MAGIC);
  	CSR_WRITE_1(sc, sc->rl_cfg3, v);
  
  	/* Config register write done. */
  	CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
  
  	v = CSR_READ_1(sc, sc->rl_cfg5);
  	v &= ~(RL_CFG5_WOL_BCAST | RL_CFG5_WOL_MCAST | RL_CFG5_WOL_UCAST);
  	v &= ~RL_CFG5_WOL_LANWAKE;
  	CSR_WRITE_1(sc, sc->rl_cfg5, v);
  }
  