FreeBSD/Linux Kernel Cross Reference
sys/dev/re/if_re.c

     /*-
      * SPDX-License-Identifier: BSD-4-Clause
      *
      * Copyright (c) 1997, 1998-2003
      *      Bill Paul <wpaul@windriver.com>.  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 8139C+/8169/8169S/8110S/8168/8111/8101E PCI NIC driver
     *
     * Written by Bill Paul <wpaul@windriver.com>
     * Senior Networking Software Engineer
     * Wind River Systems
     */
    
    /*
     * This driver is designed to support RealTek's next generation of
     * 10/100 and 10/100/1000 PCI ethernet controllers. There are currently
     * seven devices in this family: the RTL8139C+, the RTL8169, the RTL8169S,
     * RTL8110S, the RTL8168, the RTL8111 and the RTL8101E.
     *
     * The 8139C+ is a 10/100 ethernet chip. It is backwards compatible
     * with the older 8139 family, however it also supports a special
     * C+ mode of operation that provides several new performance enhancing
     * features. These include:
     *
     *      o Descriptor based DMA mechanism. Each descriptor represents
     *        a single packet fragment. Data buffers may be aligned on
     *        any byte boundary.
     *
     *      o 64-bit DMA
     *
     *      o TCP/IP checksum offload for both RX and TX
     *
     *      o High and normal priority transmit DMA rings
     *
     *      o VLAN tag insertion and extraction
     *
     *      o TCP large send (segmentation offload)
     *
     * Like the 8139, the 8139C+ also has a built-in 10/100 PHY. The C+
     * programming API is fairly straightforward. The RX filtering, EEPROM
     * access and PHY access is the same as it is on the older 8139 series
     * chips.
     *
     * The 8169 is a 64-bit 10/100/1000 gigabit ethernet MAC. It has almost the
     * same programming API and feature set as the 8139C+ with the following
     * differences and additions:
     *
     *      o 1000Mbps mode
     *
     *      o Jumbo frames
     *
     *      o GMII and TBI ports/registers for interfacing with copper
     *        or fiber PHYs
     *
     *      o RX and TX DMA rings can have up to 1024 descriptors
     *        (the 8139C+ allows a maximum of 64)
     *
     *      o Slight differences in register layout from the 8139C+
     *
     * The TX start and timer interrupt registers are at different locations
     * on the 8169 than they are on the 8139C+. Also, the status word in the
     * RX descriptor has a slightly different bit layout. The 8169 does not
     * have a built-in PHY. Most reference boards use a Marvell 88E1000 'Alaska'
     * copper gigE PHY.
     *
     * The 8169S/8110S 10/100/1000 devices have built-in copper gigE PHYs
     * (the 'S' stands for 'single-chip'). These devices have the same
    * programming API as the older 8169, but also have some vendor-specific
    * registers for the on-board PHY. The 8110S is a LAN-on-motherboard
    * part designed to be pin-compatible with the RealTek 8100 10/100 chip.
    *
    * This driver takes advantage of the RX and TX checksum offload and
    * VLAN tag insertion/extraction features. It also implements TX
    * interrupt moderation using the timer interrupt registers, which
    * significantly reduces TX interrupt load. There is also support
    * for jumbo frames, however the 8169/8169S/8110S can not transmit
    * jumbo frames larger than 7440, so the max MTU possible with this
    * driver is 7422 bytes.
    */
   
   #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/module.h>
   #include <sys/kernel.h>
   #include <sys/socket.h>
   #include <sys/lock.h>
   #include <sys/mutex.h>
   #include <sys/sysctl.h>
   #include <sys/taskqueue.h>
   
   #include <net/debugnet.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/if_vlan_var.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/miivar.h>
   
   #include <dev/pci/pcireg.h>
   #include <dev/pci/pcivar.h>
   
   #include <dev/rl/if_rlreg.h>
   
   MODULE_DEPEND(re, pci, 1, 1, 1);
   MODULE_DEPEND(re, ether, 1, 1, 1);
   MODULE_DEPEND(re, miibus, 1, 1, 1);
   
   /* "device miibus" required.  See GENERIC if you get errors here. */
   #include "miibus_if.h"
   
   /* Tunables. */
   static int intr_filter = 0;
   TUNABLE_INT("hw.re.intr_filter", &intr_filter);
   static int msi_disable = 0;
   TUNABLE_INT("hw.re.msi_disable", &msi_disable);
   static int msix_disable = 0;
   TUNABLE_INT("hw.re.msix_disable", &msix_disable);
   static int prefer_iomap = 0;
   TUNABLE_INT("hw.re.prefer_iomap", &prefer_iomap);
   
   #define RE_CSUM_FEATURES    (CSUM_IP | CSUM_TCP | CSUM_UDP)
   
   /*
    * Various supported device vendors/types and their names.
    */
   static const struct rl_type re_devs[] = {
           { DLINK_VENDORID, DLINK_DEVICEID_528T, 0,
               "D-Link DGE-528(T) Gigabit Ethernet Adapter" },
           { DLINK_VENDORID, DLINK_DEVICEID_530T_REVC, 0,
               "D-Link DGE-530(T) Gigabit Ethernet Adapter" },
           { RT_VENDORID, RT_DEVICEID_8139, 0,
               "RealTek 8139C+ 10/100BaseTX" },
           { RT_VENDORID, RT_DEVICEID_8101E, 0,
               "RealTek 810xE PCIe 10/100baseTX" },
           { RT_VENDORID, RT_DEVICEID_8168, 0,
               "RealTek 8168/8111 B/C/CP/D/DP/E/F/G PCIe Gigabit Ethernet" },
           { RT_VENDORID, RT_DEVICEID_8161, 0,
               "RealTek 8168 Gigabit Ethernet" },
           { NCUBE_VENDORID, RT_DEVICEID_8168, 0,
               "TP-Link TG-3468 v2 (RTL8168) Gigabit Ethernet" },
           { RT_VENDORID, RT_DEVICEID_8169, 0,
               "RealTek 8169/8169S/8169SB(L)/8110S/8110SB(L) Gigabit Ethernet" },
           { RT_VENDORID, RT_DEVICEID_8169SC, 0,
               "RealTek 8169SC/8110SC Single-chip Gigabit Ethernet" },
           { COREGA_VENDORID, COREGA_DEVICEID_CGLAPCIGT, 0,
               "Corega CG-LAPCIGT (RTL8169S) Gigabit Ethernet" },
           { LINKSYS_VENDORID, LINKSYS_DEVICEID_EG1032, 0,
               "Linksys EG1032 (RTL8169S) Gigabit Ethernet" },
           { USR_VENDORID, USR_DEVICEID_997902, 0,
               "US Robotics 997902 (RTL8169S) Gigabit Ethernet" }
   };
   
   static const struct rl_hwrev re_hwrevs[] = {
           { RL_HWREV_8139, RL_8139, "", RL_MTU },
           { RL_HWREV_8139A, RL_8139, "A", RL_MTU },
           { RL_HWREV_8139AG, RL_8139, "A-G", RL_MTU },
           { RL_HWREV_8139B, RL_8139, "B", RL_MTU },
           { RL_HWREV_8130, RL_8139, "8130", RL_MTU },
           { RL_HWREV_8139C, RL_8139, "C", RL_MTU },
           { RL_HWREV_8139D, RL_8139, "8139D/8100B/8100C", RL_MTU },
           { RL_HWREV_8139CPLUS, RL_8139CPLUS, "C+", RL_MTU },
           { RL_HWREV_8168B_SPIN1, RL_8169, "8168", RL_JUMBO_MTU },
           { RL_HWREV_8169, RL_8169, "8169", RL_JUMBO_MTU },
           { RL_HWREV_8169S, RL_8169, "8169S", RL_JUMBO_MTU },
           { RL_HWREV_8110S, RL_8169, "8110S", RL_JUMBO_MTU },
           { RL_HWREV_8169_8110SB, RL_8169, "8169SB/8110SB", RL_JUMBO_MTU },
           { RL_HWREV_8169_8110SC, RL_8169, "8169SC/8110SC", RL_JUMBO_MTU },
           { RL_HWREV_8169_8110SBL, RL_8169, "8169SBL/8110SBL", RL_JUMBO_MTU },
           { RL_HWREV_8169_8110SCE, RL_8169, "8169SC/8110SC", RL_JUMBO_MTU },
           { RL_HWREV_8100, RL_8139, "8100", RL_MTU },
           { RL_HWREV_8101, RL_8139, "8101", RL_MTU },
           { RL_HWREV_8100E, RL_8169, "8100E", RL_MTU },
           { RL_HWREV_8101E, RL_8169, "8101E", RL_MTU },
           { RL_HWREV_8102E, RL_8169, "8102E", RL_MTU },
           { RL_HWREV_8102EL, RL_8169, "8102EL", RL_MTU },
           { RL_HWREV_8102EL_SPIN1, RL_8169, "8102EL", RL_MTU },
           { RL_HWREV_8103E, RL_8169, "8103E", RL_MTU },
           { RL_HWREV_8401E, RL_8169, "8401E", RL_MTU },
           { RL_HWREV_8402, RL_8169, "8402", RL_MTU },
           { RL_HWREV_8105E, RL_8169, "8105E", RL_MTU },
           { RL_HWREV_8105E_SPIN1, RL_8169, "8105E", RL_MTU },
           { RL_HWREV_8106E, RL_8169, "8106E", RL_MTU },
           { RL_HWREV_8168B_SPIN2, RL_8169, "8168", RL_JUMBO_MTU },
           { RL_HWREV_8168B_SPIN3, RL_8169, "8168", RL_JUMBO_MTU },
           { RL_HWREV_8168C, RL_8169, "8168C/8111C", RL_JUMBO_MTU_6K },
           { RL_HWREV_8168C_SPIN2, RL_8169, "8168C/8111C", RL_JUMBO_MTU_6K },
           { RL_HWREV_8168CP, RL_8169, "8168CP/8111CP", RL_JUMBO_MTU_6K },
           { RL_HWREV_8168D, RL_8169, "8168D/8111D", RL_JUMBO_MTU_9K },
           { RL_HWREV_8168DP, RL_8169, "8168DP/8111DP", RL_JUMBO_MTU_9K },
           { RL_HWREV_8168E, RL_8169, "8168E/8111E", RL_JUMBO_MTU_9K},
           { RL_HWREV_8168E_VL, RL_8169, "8168E/8111E-VL", RL_JUMBO_MTU_6K},
           { RL_HWREV_8168EP, RL_8169, "8168EP/8111EP", RL_JUMBO_MTU_9K},
           { RL_HWREV_8168F, RL_8169, "8168F/8111F", RL_JUMBO_MTU_9K},
           { RL_HWREV_8168G, RL_8169, "8168G/8111G", RL_JUMBO_MTU_9K},
           { RL_HWREV_8168GU, RL_8169, "8168GU/8111GU", RL_JUMBO_MTU_9K},
           { RL_HWREV_8168H, RL_8169, "8168H/8111H", RL_JUMBO_MTU_9K},
           { RL_HWREV_8411, RL_8169, "8411", RL_JUMBO_MTU_9K},
           { RL_HWREV_8411B, RL_8169, "8411B", RL_JUMBO_MTU_9K},
           { 0, 0, NULL, 0 }
   };
   
   static int re_probe             (device_t);
   static int re_attach            (device_t);
   static int re_detach            (device_t);
   
   static int re_encap             (struct rl_softc *, struct mbuf **);
   
   static void re_dma_map_addr     (void *, bus_dma_segment_t *, int, int);
   static int re_allocmem          (device_t, struct rl_softc *);
   static __inline void re_discard_rxbuf
                                   (struct rl_softc *, int);
   static int re_newbuf            (struct rl_softc *, int);
   static int re_jumbo_newbuf      (struct rl_softc *, int);
   static int re_rx_list_init      (struct rl_softc *);
   static int re_jrx_list_init     (struct rl_softc *);
   static int re_tx_list_init      (struct rl_softc *);
   #ifdef RE_FIXUP_RX
   static __inline void re_fixup_rx
                                   (struct mbuf *);
   #endif
   static int re_rxeof             (struct rl_softc *, int *);
   static void re_txeof            (struct rl_softc *);
   #ifdef DEVICE_POLLING
   static int re_poll              (struct ifnet *, enum poll_cmd, int);
   static int re_poll_locked       (struct ifnet *, enum poll_cmd, int);
   #endif
   static int re_intr              (void *);
   static void re_intr_msi         (void *);
   static void re_tick             (void *);
   static void re_int_task         (void *, int);
   static void re_start            (struct ifnet *);
   static void re_start_locked     (struct ifnet *);
   static void re_start_tx         (struct rl_softc *);
   static int re_ioctl             (struct ifnet *, u_long, caddr_t);
   static void re_init             (void *);
   static void re_init_locked      (struct rl_softc *);
   static void re_stop             (struct rl_softc *);
   static void re_watchdog         (struct rl_softc *);
   static int re_suspend           (device_t);
   static int re_resume            (device_t);
   static int re_shutdown          (device_t);
   static int re_ifmedia_upd       (struct ifnet *);
   static void re_ifmedia_sts      (struct ifnet *, struct ifmediareq *);
   
   static void re_eeprom_putbyte   (struct rl_softc *, int);
   static void re_eeprom_getword   (struct rl_softc *, int, u_int16_t *);
   static void re_read_eeprom      (struct rl_softc *, caddr_t, int, int);
   static int re_gmii_readreg      (device_t, int, int);
   static int re_gmii_writereg     (device_t, int, int, int);
   
   static int re_miibus_readreg    (device_t, int, int);
   static int re_miibus_writereg   (device_t, int, int, int);
   static void re_miibus_statchg   (device_t);
   
   static void re_set_jumbo        (struct rl_softc *, int);
   static void re_set_rxmode               (struct rl_softc *);
   static void re_reset            (struct rl_softc *);
   static void re_setwol           (struct rl_softc *);
   static void re_clrwol           (struct rl_softc *);
   static void re_set_linkspeed    (struct rl_softc *);
   
   DEBUGNET_DEFINE(re);
   
   #ifdef DEV_NETMAP       /* see ixgbe.c for details */
   #include <dev/netmap/if_re_netmap.h>
   MODULE_DEPEND(re, netmap, 1, 1, 1);
   #endif /* !DEV_NETMAP */
   
   #ifdef RE_DIAG
   static int re_diag              (struct rl_softc *);
   #endif
   
   static void re_add_sysctls      (struct rl_softc *);
   static int re_sysctl_stats      (SYSCTL_HANDLER_ARGS);
   static int sysctl_int_range     (SYSCTL_HANDLER_ARGS, int, int);
   static int sysctl_hw_re_int_mod (SYSCTL_HANDLER_ARGS);
   
   static device_method_t re_methods[] = {
           /* Device interface */
           DEVMETHOD(device_probe,         re_probe),
           DEVMETHOD(device_attach,        re_attach),
           DEVMETHOD(device_detach,        re_detach),
           DEVMETHOD(device_suspend,       re_suspend),
           DEVMETHOD(device_resume,        re_resume),
           DEVMETHOD(device_shutdown,      re_shutdown),
   
           /* MII interface */
           DEVMETHOD(miibus_readreg,       re_miibus_readreg),
           DEVMETHOD(miibus_writereg,      re_miibus_writereg),
           DEVMETHOD(miibus_statchg,       re_miibus_statchg),
   
           DEVMETHOD_END
   };
   
   static driver_t re_driver = {
           "re",
           re_methods,
           sizeof(struct rl_softc)
   };
   
   DRIVER_MODULE(re, pci, re_driver, 0, 0);
   DRIVER_MODULE(miibus, re, miibus_driver, 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
   re_eeprom_putbyte(struct rl_softc *sc, int addr)
   {
           int                     d, i;
   
           d = addr | (RL_9346_READ << sc->rl_eewidth);
   
           /*
            * Feed in each bit and strobe the clock.
            */
   
           for (i = 1 << (sc->rl_eewidth + 3); 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
   re_eeprom_getword(struct rl_softc *sc, int addr, u_int16_t *dest)
   {
           int                     i;
           u_int16_t               word = 0;
   
           /*
            * Send address of word we want to read.
            */
           re_eeprom_putbyte(sc, addr);
   
           /*
            * 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);
           }
   
           *dest = word;
   }
   
   /*
    * Read a sequence of words from the EEPROM.
    */
   static void
   re_read_eeprom(struct rl_softc *sc, caddr_t dest, int off, int cnt)
   {
           int                     i;
           u_int16_t               word = 0, *ptr;
   
           CSR_SETBIT_1(sc, RL_EECMD, RL_EEMODE_PROGRAM);
   
           DELAY(100);
   
           for (i = 0; i < cnt; i++) {
                   CSR_SETBIT_1(sc, RL_EECMD, RL_EE_SEL);
                   re_eeprom_getword(sc, off + i, &word);
                   CSR_CLRBIT_1(sc, RL_EECMD, RL_EE_SEL);
                   ptr = (u_int16_t *)(dest + (i * 2));
                   *ptr = word;
           }
   
           CSR_CLRBIT_1(sc, RL_EECMD, RL_EEMODE_PROGRAM);
   }
   
   static int
   re_gmii_readreg(device_t dev, int phy, int reg)
   {
           struct rl_softc         *sc;
           u_int32_t               rval;
           int                     i;
   
           sc = device_get_softc(dev);
   
           /* Let the rgephy driver read the GMEDIASTAT register */
   
           if (reg == RL_GMEDIASTAT) {
                   rval = CSR_READ_1(sc, RL_GMEDIASTAT);
                   return (rval);
           }
   
           CSR_WRITE_4(sc, RL_PHYAR, reg << 16);
   
           for (i = 0; i < RL_PHY_TIMEOUT; i++) {
                   rval = CSR_READ_4(sc, RL_PHYAR);
                   if (rval & RL_PHYAR_BUSY)
                           break;
                   DELAY(25);
           }
   
           if (i == RL_PHY_TIMEOUT) {
                   device_printf(sc->rl_dev, "PHY read failed\n");
                   return (0);
           }
   
           /*
            * Controller requires a 20us delay to process next MDIO request.
            */
           DELAY(20);
   
           return (rval & RL_PHYAR_PHYDATA);
   }
   
   static int
   re_gmii_writereg(device_t dev, int phy, int reg, int data)
   {
           struct rl_softc         *sc;
           u_int32_t               rval;
           int                     i;
   
           sc = device_get_softc(dev);
   
           CSR_WRITE_4(sc, RL_PHYAR, (reg << 16) |
               (data & RL_PHYAR_PHYDATA) | RL_PHYAR_BUSY);
   
           for (i = 0; i < RL_PHY_TIMEOUT; i++) {
                   rval = CSR_READ_4(sc, RL_PHYAR);
                   if (!(rval & RL_PHYAR_BUSY))
                           break;
                   DELAY(25);
           }
   
           if (i == RL_PHY_TIMEOUT) {
                   device_printf(sc->rl_dev, "PHY write failed\n");
                   return (0);
           }
   
           /*
            * Controller requires a 20us delay to process next MDIO request.
            */
           DELAY(20);
   
           return (0);
   }
   
   static int
   re_miibus_readreg(device_t dev, int phy, int reg)
   {
           struct rl_softc         *sc;
           u_int16_t               rval = 0;
           u_int16_t               re8139_reg = 0;
   
           sc = device_get_softc(dev);
   
           if (sc->rl_type == RL_8169) {
                   rval = re_gmii_readreg(dev, phy, reg);
                   return (rval);
           }
   
           switch (reg) {
           case MII_BMCR:
                   re8139_reg = RL_BMCR;
                   break;
           case MII_BMSR:
                   re8139_reg = RL_BMSR;
                   break;
           case MII_ANAR:
                   re8139_reg = RL_ANAR;
                   break;
           case MII_ANER:
                   re8139_reg = RL_ANER;
                   break;
           case MII_ANLPAR:
                   re8139_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:
                   rval = CSR_READ_1(sc, RL_MEDIASTAT);
                   return (rval);
           default:
                   device_printf(sc->rl_dev, "bad phy register\n");
                   return (0);
           }
           rval = CSR_READ_2(sc, re8139_reg);
           if (sc->rl_type == RL_8139CPLUS && re8139_reg == RL_BMCR) {
                   /* 8139C+ has different bit layout. */
                   rval &= ~(BMCR_LOOP | BMCR_ISO);
           }
           return (rval);
   }
   
   static int
   re_miibus_writereg(device_t dev, int phy, int reg, int data)
   {
           struct rl_softc         *sc;
           u_int16_t               re8139_reg = 0;
           int                     rval = 0;
   
           sc = device_get_softc(dev);
   
           if (sc->rl_type == RL_8169) {
                   rval = re_gmii_writereg(dev, phy, reg, data);
                   return (rval);
           }
   
           switch (reg) {
           case MII_BMCR:
                   re8139_reg = RL_BMCR;
                   if (sc->rl_type == RL_8139CPLUS) {
                           /* 8139C+ has different bit layout. */
                           data &= ~(BMCR_LOOP | BMCR_ISO);
                   }
                   break;
           case MII_BMSR:
                   re8139_reg = RL_BMSR;
                   break;
           case MII_ANAR:
                   re8139_reg = RL_ANAR;
                   break;
           case MII_ANER:
                   re8139_reg = RL_ANER;
                   break;
           case MII_ANLPAR:
                   re8139_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, re8139_reg, data);
           return (0);
   }
   
   static void
   re_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;
                   case IFM_1000_T:
                           if ((sc->rl_flags & RL_FLAG_FASTETHER) != 0)
                                   break;
                           sc->rl_flags |= RL_FLAG_LINK;
                           break;
                   default:
                           break;
                   }
           }
           /*
            * RealTek controllers do not provide any interface to the RX/TX
            * MACs for resolved speed, duplex and flow-control parameters.
            */
   }
   
   static u_int
   re_hash_maddr(void *arg, struct sockaddr_dl *sdl, u_int cnt)
   {
           uint32_t h, *hashes = arg;
   
           h = ether_crc32_be(LLADDR(sdl), ETHER_ADDR_LEN) >> 26;
           if (h < 32)
                   hashes[0] |= (1 << h);
           else
                   hashes[1] |= (1 << (h - 32));
   
           return (1);
   }
   
   /*
    * Set the RX configuration and 64-bit multicast hash filter.
    */
   static void
   re_set_rxmode(struct rl_softc *sc)
   {
           struct ifnet            *ifp;
           uint32_t                h, hashes[2] = { 0, 0 };
           uint32_t                rxfilt;
   
           RL_LOCK_ASSERT(sc);
   
           ifp = sc->rl_ifp;
   
           rxfilt = RL_RXCFG_CONFIG | RL_RXCFG_RX_INDIV | RL_RXCFG_RX_BROAD;
           if ((sc->rl_flags & RL_FLAG_EARLYOFF) != 0)
                   rxfilt |= RL_RXCFG_EARLYOFF;
           else if ((sc->rl_flags & RL_FLAG_8168G_PLUS) != 0)
                   rxfilt |= RL_RXCFG_EARLYOFFV2;
   
           if (ifp->if_flags & (IFF_ALLMULTI | IFF_PROMISC)) {
                   if (ifp->if_flags & IFF_PROMISC)
                           rxfilt |= RL_RXCFG_RX_ALLPHYS;
                   /*
                    * Unlike other hardwares, we have to explicitly set
                    * RL_RXCFG_RX_MULTI to receive multicast frames in
                    * promiscuous mode.
                    */
                   rxfilt |= RL_RXCFG_RX_MULTI;
                   hashes[0] = hashes[1] = 0xffffffff;
                   goto done;
           }
   
           if_foreach_llmaddr(ifp, re_hash_maddr, hashes);
   
           if (hashes[0] != 0 || hashes[1] != 0) {
                   /*
                    * For some unfathomable reason, RealTek decided to
                    * reverse the order of the multicast hash registers
                    * in the PCI Express parts.  This means we have to
                    * write the hash pattern in reverse order for those
                    * devices.
                    */
                   if ((sc->rl_flags & RL_FLAG_PCIE) != 0) {
                           h = bswap32(hashes[0]);
                           hashes[0] = bswap32(hashes[1]);
                           hashes[1] = h;
                   }
                   rxfilt |= RL_RXCFG_RX_MULTI;
           }
   
           if  (sc->rl_hwrev->rl_rev == RL_HWREV_8168F) {
                   /* Disable multicast filtering due to silicon bug. */
                   hashes[0] = 0xffffffff;
                   hashes[1] = 0xffffffff;
           }
   
   done:
           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
   re_reset(struct rl_softc *sc)
   {
           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");
   
           if ((sc->rl_flags & RL_FLAG_MACRESET) != 0)
                   CSR_WRITE_1(sc, 0x82, 1);
           if (sc->rl_hwrev->rl_rev == RL_HWREV_8169S)
                   re_gmii_writereg(sc->rl_dev, 1, 0x0b, 0);
   }
   
   #ifdef RE_DIAG
   
   /*
    * The following routine is designed to test for a defect on some
    * 32-bit 8169 cards. Some of these NICs have the REQ64# and ACK64#
    * lines connected to the bus, however for a 32-bit only card, they
    * should be pulled high. The result of this defect is that the
    * NIC will not work right if you plug it into a 64-bit slot: DMA
    * operations will be done with 64-bit transfers, which will fail
    * because the 64-bit data lines aren't connected.
    *
    * There's no way to work around this (short of talking a soldering
    * iron to the board), however we can detect it. The method we use
    * here is to put the NIC into digital loopback mode, set the receiver
    * to promiscuous mode, and then try to send a frame. We then compare
    * the frame data we sent to what was received. If the data matches,
    * then the NIC is working correctly, otherwise we know the user has
    * a defective NIC which has been mistakenly plugged into a 64-bit PCI
    * slot. In the latter case, there's no way the NIC can work correctly,
    * so we print out a message on the console and abort the device attach.
    */
   
   static int
   re_diag(struct rl_softc *sc)
   {
           struct ifnet            *ifp = sc->rl_ifp;
           struct mbuf             *m0;
           struct ether_header     *eh;
           struct rl_desc          *cur_rx;
           u_int16_t               status;
           u_int32_t               rxstat;
           int                     total_len, i, error = 0, phyaddr;
           u_int8_t                dst[] = { 0x00, 'h', 'e', 'l', 'l', 'o' };
           u_int8_t                src[] = { 0x00, 'w', 'o', 'r', 'l', 'd' };
   
           /* Allocate a single mbuf */
           MGETHDR(m0, M_NOWAIT, MT_DATA);
           if (m0 == NULL)
                   return (ENOBUFS);
   
           RL_LOCK(sc);
   
           /*
            * Initialize the NIC in test mode. This sets the chip up
            * so that it can send and receive frames, but performs the
            * following special functions:
            * - Puts receiver in promiscuous mode
            * - Enables digital loopback mode
            * - Leaves interrupts turned off
            */
   
           ifp->if_flags |= IFF_PROMISC;
           sc->rl_testmode = 1;
           ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
           re_init_locked(sc);
           sc->rl_flags |= RL_FLAG_LINK;
           if (sc->rl_type == RL_8169)
                   phyaddr = 1;
           else
                   phyaddr = 0;
   
           re_miibus_writereg(sc->rl_dev, phyaddr, MII_BMCR, BMCR_RESET);
           for (i = 0; i < RL_TIMEOUT; i++) {
                   status = re_miibus_readreg(sc->rl_dev, phyaddr, MII_BMCR);
                   if (!(status & BMCR_RESET))
                           break;
           }
   
           re_miibus_writereg(sc->rl_dev, phyaddr, MII_BMCR, BMCR_LOOP);
           CSR_WRITE_2(sc, RL_ISR, RL_INTRS);
   
           DELAY(100000);
   
           /* Put some data in the mbuf */
   
           eh = mtod(m0, struct ether_header *);
           bcopy ((char *)&dst, eh->ether_dhost, ETHER_ADDR_LEN);
           bcopy ((char *)&src, eh->ether_shost, ETHER_ADDR_LEN);
           eh->ether_type = htons(ETHERTYPE_IP);
           m0->m_pkthdr.len = m0->m_len = ETHER_MIN_LEN - ETHER_CRC_LEN;
   
           /*
            * Queue the packet, start transmission.
            * Note: IF_HANDOFF() ultimately calls re_start() for us.
            */
   
           CSR_WRITE_2(sc, RL_ISR, 0xFFFF);
           RL_UNLOCK(sc);
           /* XXX: re_diag must not be called when in ALTQ mode */
           IF_HANDOFF(&ifp->if_snd, m0, ifp);
           RL_LOCK(sc);
           m0 = NULL;
   
           /* Wait for it to propagate through the chip */
   
           DELAY(100000);
           for (i = 0; i < RL_TIMEOUT; i++) {
                   status = CSR_READ_2(sc, RL_ISR);
                   CSR_WRITE_2(sc, RL_ISR, status);
                   if ((status & (RL_ISR_TIMEOUT_EXPIRED|RL_ISR_RX_OK)) ==
                       (RL_ISR_TIMEOUT_EXPIRED|RL_ISR_RX_OK))
                           break;
                   DELAY(10);
           }
   
           if (i == RL_TIMEOUT) {
                   device_printf(sc->rl_dev,
                       "diagnostic failed, failed to receive packet in"
                       " loopback mode\n");
                   error = EIO;
                   goto done;
           }
   
           /*
            * The packet should have been dumped into the first
            * entry in the RX DMA ring. Grab it from there.
            */
   
           bus_dmamap_sync(sc->rl_ldata.rl_rx_list_tag,
               sc->rl_ldata.rl_rx_list_map,
               BUS_DMASYNC_POSTREAD);
           bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag,
               sc->rl_ldata.rl_rx_desc[0].rx_dmamap,
               BUS_DMASYNC_POSTREAD);
           bus_dmamap_unload(sc->rl_ldata.rl_rx_mtag,
               sc->rl_ldata.rl_rx_desc[0].rx_dmamap);
   
           m0 = sc->rl_ldata.rl_rx_desc[0].rx_m;
           sc->rl_ldata.rl_rx_desc[0].rx_m = NULL;
           eh = mtod(m0, struct ether_header *);
   
           cur_rx = &sc->rl_ldata.rl_rx_list[0];
           total_len = RL_RXBYTES(cur_rx);
           rxstat = le32toh(cur_rx->rl_cmdstat);
   
           if (total_len != ETHER_MIN_LEN) {
                   device_printf(sc->rl_dev,
                       "diagnostic failed, received short packet\n");
                   error = EIO;
                   goto done;
           }
   
           /* Test that the received packet data matches what we sent. */
   
           if (bcmp((char *)&eh->ether_dhost, (char *)&dst, ETHER_ADDR_LEN) ||
               bcmp((char *)&eh->ether_shost, (char *)&src, ETHER_ADDR_LEN) ||
               ntohs(eh->ether_type) != ETHERTYPE_IP) {
                   device_printf(sc->rl_dev, "WARNING, DMA FAILURE!\n");
                   device_printf(sc->rl_dev, "expected TX data: %6D/%6D/0x%x\n",
                       dst, ":", src, ":", ETHERTYPE_IP);
                   device_printf(sc->rl_dev, "received RX data: %6D/%6D/0x%x\n",
                       eh->ether_dhost, ":", eh->ether_shost, ":",
                       ntohs(eh->ether_type));
                   device_printf(sc->rl_dev, "You may have a defective 32-bit "
                       "NIC plugged into a 64-bit PCI slot.\n");
                   device_printf(sc->rl_dev, "Please re-install the NIC in a "
                       "32-bit slot for proper operation.\n");
                   device_printf(sc->rl_dev, "Read the re(4) man page for more "
                       "details.\n");
                   error = EIO;
           }
   
   done:
           /* Turn interface off, release resources */
   
           sc->rl_testmode = 0;
           sc->rl_flags &= ~RL_FLAG_LINK;
           ifp->if_flags &= ~IFF_PROMISC;
           re_stop(sc);
           if (m0 != NULL)
                   m_freem(m0);
   
           RL_UNLOCK(sc);
   
           return (error);
   }
   
   #endif
   
   /*
    * Probe for a RealTek 8139C+/8169/8110 chip. Check the PCI vendor and device
    * IDs against our list and return a device name if we find a match.
    */
   static int
   re_probe(device_t dev)
   {
           const struct rl_type    *t;
           uint16_t                devid, vendor;
           uint16_t                revid, sdevid;
           int                     i;
   
           vendor = pci_get_vendor(dev);
           devid = pci_get_device(dev);
           revid = pci_get_revid(dev);
           sdevid = pci_get_subdevice(dev);
   
           if (vendor == LINKSYS_VENDORID && devid == LINKSYS_DEVICEID_EG1032) {
                   if (sdevid != LINKSYS_SUBDEVICE_EG1032_REV3) {
                           /*
                            * Only attach to rev. 3 of the Linksys EG1032 adapter.
                            * Rev. 2 is supported by sk(4).
                            */
                           return (ENXIO);
                   }
           }
   
           if (vendor == RT_VENDORID && devid == RT_DEVICEID_8139) {
                   if (revid != 0x20) {
                           /* 8139, let rl(4) take care of this device. */
                           return (ENXIO);
                   }
           }
   
           t = re_devs;
           for (i = 0; i < nitems(re_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);
   }
   
   /*
    * Map a single buffer address.
    */
   
   static void
   re_dma_map_addr(void *arg, bus_dma_segment_t *segs, int nseg, int error)
   {
           bus_addr_t              *addr;
   
           if (error)
                   return;
   
           KASSERT(nseg == 1, ("too many DMA segments, %d should be 1", nseg));
           addr = arg;
           *addr = segs->ds_addr;
   }
   
   static int
   re_allocmem(device_t dev, struct rl_softc *sc)
   {
           bus_addr_t              lowaddr;
           bus_size_t              rx_list_size, tx_list_size;
           int                     error;
           int                     i;
  
          rx_list_size = sc->rl_ldata.rl_rx_desc_cnt * sizeof(struct rl_desc);
          tx_list_size = sc->rl_ldata.rl_tx_desc_cnt * sizeof(struct rl_desc);
  
          /*
           * Allocate the parent bus DMA tag appropriate for PCI.
           * In order to use DAC, RL_CPLUSCMD_PCI_DAC bit of RL_CPLUS_CMD
           * register should be set. However some RealTek chips are known
           * to be buggy on DAC handling, therefore disable DAC by limiting
           * DMA address space to 32bit. PCIe variants of RealTek chips
           * may not have the limitation.
           */
          lowaddr = BUS_SPACE_MAXADDR;
          if ((sc->rl_flags & RL_FLAG_PCIE) == 0)
                  lowaddr = BUS_SPACE_MAXADDR_32BIT;
          error = bus_dma_tag_create(bus_get_dma_tag(dev), 1, 0,
              lowaddr, BUS_SPACE_MAXADDR, NULL, NULL,
              BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT, 0,
              NULL, NULL, &sc->rl_parent_tag);
          if (error) {
                  device_printf(dev, "could not allocate parent DMA tag\n");
                  return (error);
          }
  
          /*
           * Allocate map for TX mbufs.
           */
          error = bus_dma_tag_create(sc->rl_parent_tag, 1, 0,
              BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL,
              NULL, MCLBYTES * RL_NTXSEGS, RL_NTXSEGS, 4096, 0,
              NULL, NULL, &sc->rl_ldata.rl_tx_mtag);
          if (error) {
                  device_printf(dev, "could not allocate TX DMA tag\n");
                  return (error);
          }
  
          /*
           * Allocate map for RX mbufs.
           */
  
          if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0) {
                  error = bus_dma_tag_create(sc->rl_parent_tag, sizeof(uint64_t),
                      0, BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
                      MJUM9BYTES, 1, MJUM9BYTES, 0, NULL, NULL,
                      &sc->rl_ldata.rl_jrx_mtag);
                  if (error) {
                          device_printf(dev,
                              "could not allocate jumbo RX DMA tag\n");
                          return (error);
                  }
          }
          error = bus_dma_tag_create(sc->rl_parent_tag, sizeof(uint64_t), 0,
              BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
              MCLBYTES, 1, MCLBYTES, 0, NULL, NULL, &sc->rl_ldata.rl_rx_mtag);
          if (error) {
                  device_printf(dev, "could not allocate RX DMA tag\n");
                  return (error);
          }
  
          /*
           * Allocate map for TX descriptor list.
           */
          error = bus_dma_tag_create(sc->rl_parent_tag, RL_RING_ALIGN,
              0, BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL,
              NULL, tx_list_size, 1, tx_list_size, 0,
              NULL, NULL, &sc->rl_ldata.rl_tx_list_tag);
          if (error) {
                  device_printf(dev, "could not allocate TX DMA ring tag\n");
                  return (error);
          }
  
          /* Allocate DMA'able memory for the TX ring */
  
          error = bus_dmamem_alloc(sc->rl_ldata.rl_tx_list_tag,
              (void **)&sc->rl_ldata.rl_tx_list,
              BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
              &sc->rl_ldata.rl_tx_list_map);
          if (error) {
                  device_printf(dev, "could not allocate TX DMA ring\n");
                  return (error);
          }
  
          /* Load the map for the TX ring. */
  
          sc->rl_ldata.rl_tx_list_addr = 0;
          error = bus_dmamap_load(sc->rl_ldata.rl_tx_list_tag,
               sc->rl_ldata.rl_tx_list_map, sc->rl_ldata.rl_tx_list,
               tx_list_size, re_dma_map_addr,
               &sc->rl_ldata.rl_tx_list_addr, BUS_DMA_NOWAIT);
          if (error != 0 || sc->rl_ldata.rl_tx_list_addr == 0) {
                  device_printf(dev, "could not load TX DMA ring\n");
                  return (ENOMEM);
          }
  
          /* Create DMA maps for TX buffers */
  
          for (i = 0; i < sc->rl_ldata.rl_tx_desc_cnt; i++) {
                  error = bus_dmamap_create(sc->rl_ldata.rl_tx_mtag, 0,
                      &sc->rl_ldata.rl_tx_desc[i].tx_dmamap);
                  if (error) {
                          device_printf(dev, "could not create DMA map for TX\n");
                          return (error);
                  }
          }
  
          /*
           * Allocate map for RX descriptor list.
           */
          error = bus_dma_tag_create(sc->rl_parent_tag, RL_RING_ALIGN,
              0, BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL,
              NULL, rx_list_size, 1, rx_list_size, 0,
              NULL, NULL, &sc->rl_ldata.rl_rx_list_tag);
          if (error) {
                  device_printf(dev, "could not create RX DMA ring tag\n");
                  return (error);
          }
  
          /* Allocate DMA'able memory for the RX ring */
  
          error = bus_dmamem_alloc(sc->rl_ldata.rl_rx_list_tag,
              (void **)&sc->rl_ldata.rl_rx_list,
              BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
              &sc->rl_ldata.rl_rx_list_map);
          if (error) {
                  device_printf(dev, "could not allocate RX DMA ring\n");
                  return (error);
          }
  
          /* Load the map for the RX ring. */
  
          sc->rl_ldata.rl_rx_list_addr = 0;
          error = bus_dmamap_load(sc->rl_ldata.rl_rx_list_tag,
               sc->rl_ldata.rl_rx_list_map, sc->rl_ldata.rl_rx_list,
               rx_list_size, re_dma_map_addr,
               &sc->rl_ldata.rl_rx_list_addr, BUS_DMA_NOWAIT);
          if (error != 0 || sc->rl_ldata.rl_rx_list_addr == 0) {
                  device_printf(dev, "could not load RX DMA ring\n");
                  return (ENOMEM);
          }
  
          /* Create DMA maps for RX buffers */
  
          if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0) {
                  error = bus_dmamap_create(sc->rl_ldata.rl_jrx_mtag, 0,
                      &sc->rl_ldata.rl_jrx_sparemap);
                  if (error) {
                          device_printf(dev,
                              "could not create spare DMA map for jumbo RX\n");
                          return (error);
                  }
                  for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                          error = bus_dmamap_create(sc->rl_ldata.rl_jrx_mtag, 0,
                              &sc->rl_ldata.rl_jrx_desc[i].rx_dmamap);
                          if (error) {
                                  device_printf(dev,
                                      "could not create DMA map for jumbo RX\n");
                                  return (error);
                          }
                  }
          }
          error = bus_dmamap_create(sc->rl_ldata.rl_rx_mtag, 0,
              &sc->rl_ldata.rl_rx_sparemap);
          if (error) {
                  device_printf(dev, "could not create spare DMA map for RX\n");
                  return (error);
          }
          for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                  error = bus_dmamap_create(sc->rl_ldata.rl_rx_mtag, 0,
                      &sc->rl_ldata.rl_rx_desc[i].rx_dmamap);
                  if (error) {
                          device_printf(dev, "could not create DMA map for RX\n");
                          return (error);
                  }
          }
  
          /* Create DMA map for statistics. */
          error = bus_dma_tag_create(sc->rl_parent_tag, RL_DUMP_ALIGN, 0,
              BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
              sizeof(struct rl_stats), 1, sizeof(struct rl_stats), 0, NULL, NULL,
              &sc->rl_ldata.rl_stag);
          if (error) {
                  device_printf(dev, "could not create statistics DMA tag\n");
                  return (error);
          }
          /* Allocate DMA'able memory for statistics. */
          error = bus_dmamem_alloc(sc->rl_ldata.rl_stag,
              (void **)&sc->rl_ldata.rl_stats,
              BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
              &sc->rl_ldata.rl_smap);
          if (error) {
                  device_printf(dev,
                      "could not allocate statistics DMA memory\n");
                  return (error);
          }
          /* Load the map for statistics. */
          sc->rl_ldata.rl_stats_addr = 0;
          error = bus_dmamap_load(sc->rl_ldata.rl_stag, sc->rl_ldata.rl_smap,
              sc->rl_ldata.rl_stats, sizeof(struct rl_stats), re_dma_map_addr,
               &sc->rl_ldata.rl_stats_addr, BUS_DMA_NOWAIT);
          if (error != 0 || sc->rl_ldata.rl_stats_addr == 0) {
                  device_printf(dev, "could not load statistics DMA memory\n");
                  return (ENOMEM);
          }
  
          return (0);
  }
  
  /*
   * Attach the interface. Allocate softc structures, do ifmedia
   * setup and ethernet/BPF attach.
   */
  static int
  re_attach(device_t dev)
  {
          u_char                  eaddr[ETHER_ADDR_LEN];
          u_int16_t               as[ETHER_ADDR_LEN / 2];
          struct rl_softc         *sc;
          struct ifnet            *ifp;
          const struct rl_hwrev   *hw_rev;
          int                     capmask, error = 0, hwrev, i, msic, msixc,
                                  phy, reg, rid;
          u_int32_t               cap, ctl;
          u_int16_t               devid, re_did = 0;
          uint8_t                 cfg;
  
          sc = device_get_softc(dev);
          sc->rl_dev = dev;
  
          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);
  
          /*
           * Map control/status registers.
           */
          pci_enable_busmaster(dev);
  
          devid = pci_get_device(dev);
          /*
           * Prefer memory space register mapping over IO space.
           * Because RTL8169SC does not seem to work when memory mapping
           * is used always activate io mapping.
           */
          if (devid == RT_DEVICEID_8169SC)
                  prefer_iomap = 1;
          if (prefer_iomap == 0) {
                  sc->rl_res_id = PCIR_BAR(1);
                  sc->rl_res_type = SYS_RES_MEMORY;
                  /* RTL8168/8101E seems to use different BARs. */
                  if (devid == RT_DEVICEID_8168 || devid == RT_DEVICEID_8101E)
                          sc->rl_res_id = PCIR_BAR(2);
          } else {
                  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 (sc->rl_res == NULL && prefer_iomap == 0) {
                  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 (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);
  
          msic = pci_msi_count(dev);
          msixc = pci_msix_count(dev);
          if (pci_find_cap(dev, PCIY_EXPRESS, &reg) == 0) {
                  sc->rl_flags |= RL_FLAG_PCIE;
                  sc->rl_expcap = reg;
          }
          if (bootverbose) {
                  device_printf(dev, "MSI count : %d\n", msic);
                  device_printf(dev, "MSI-X count : %d\n", msixc);
          }
          if (msix_disable > 0)
                  msixc = 0;
          if (msi_disable > 0)
                  msic = 0;
          /* Prefer MSI-X to MSI. */
          if (msixc > 0) {
                  msixc = RL_MSI_MESSAGES;
                  rid = PCIR_BAR(4);
                  sc->rl_res_pba = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
                      &rid, RF_ACTIVE);
                  if (sc->rl_res_pba == NULL) {
                          device_printf(sc->rl_dev,
                              "could not allocate MSI-X PBA resource\n");
                  }
                  if (sc->rl_res_pba != NULL &&
                      pci_alloc_msix(dev, &msixc) == 0) {
                          if (msixc == RL_MSI_MESSAGES) {
                                  device_printf(dev, "Using %d MSI-X message\n",
                                      msixc);
                                  sc->rl_flags |= RL_FLAG_MSIX;
                          } else
                                  pci_release_msi(dev);
                  }
                  if ((sc->rl_flags & RL_FLAG_MSIX) == 0) {
                          if (sc->rl_res_pba != NULL)
                                  bus_release_resource(dev, SYS_RES_MEMORY, rid,
                                      sc->rl_res_pba);
                          sc->rl_res_pba = NULL;
                          msixc = 0;
                  }
          }
          /* Prefer MSI to INTx. */
          if (msixc == 0 && msic > 0) {
                  msic = RL_MSI_MESSAGES;
                  if (pci_alloc_msi(dev, &msic) == 0) {
                          if (msic == RL_MSI_MESSAGES) {
                                  device_printf(dev, "Using %d MSI message\n",
                                      msic);
                                  sc->rl_flags |= RL_FLAG_MSI;
                                  /* Explicitly set MSI enable bit. */
                                  CSR_WRITE_1(sc, RL_EECMD, RL_EE_MODE);
                                  cfg = CSR_READ_1(sc, RL_CFG2);
                                  cfg |= RL_CFG2_MSI;
                                  CSR_WRITE_1(sc, RL_CFG2, cfg);
                                  CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
                          } else
                                  pci_release_msi(dev);
                  }
                  if ((sc->rl_flags & RL_FLAG_MSI) == 0)
                          msic = 0;
          }
  
          /* Allocate interrupt */
          if ((sc->rl_flags & (RL_FLAG_MSI | RL_FLAG_MSIX)) == 0) {
                  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 allocate IRQ resources\n");
                          error = ENXIO;
                          goto fail;
                  }
          } else {
                  for (i = 0, rid = 1; i < RL_MSI_MESSAGES; i++, rid++) {
                          sc->rl_irq[i] = bus_alloc_resource_any(dev,
                              SYS_RES_IRQ, &rid, RF_ACTIVE);
                          if (sc->rl_irq[i] == NULL) {
                                  device_printf(dev,
                                      "couldn't allocate IRQ resources for "
                                      "message %d\n", rid);
                                  error = ENXIO;
                                  goto fail;
                          }
                  }
          }
  
          if ((sc->rl_flags & RL_FLAG_MSI) == 0) {
                  CSR_WRITE_1(sc, RL_EECMD, RL_EE_MODE);
                  cfg = CSR_READ_1(sc, RL_CFG2);
                  if ((cfg & RL_CFG2_MSI) != 0) {
                          device_printf(dev, "turning off MSI enable bit.\n");
                          cfg &= ~RL_CFG2_MSI;
                          CSR_WRITE_1(sc, RL_CFG2, cfg);
                  }
                  CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
          }
  
          /* Disable ASPM L0S/L1 and CLKREQ. */
          if (sc->rl_expcap != 0) {
                  cap = pci_read_config(dev, sc->rl_expcap +
                      PCIER_LINK_CAP, 2);
                  if ((cap & PCIEM_LINK_CAP_ASPM) != 0) {
                          ctl = pci_read_config(dev, sc->rl_expcap +
                              PCIER_LINK_CTL, 2);
                          if ((ctl & (PCIEM_LINK_CTL_ECPM |
                              PCIEM_LINK_CTL_ASPMC))!= 0) {
                                  ctl &= ~(PCIEM_LINK_CTL_ECPM |
                                      PCIEM_LINK_CTL_ASPMC);
                                  pci_write_config(dev, sc->rl_expcap +
                                      PCIER_LINK_CTL, ctl, 2);
                                  device_printf(dev, "ASPM disabled\n");
                          }
                  } else
                          device_printf(dev, "no ASPM capability\n");
          }
  
          hw_rev = re_hwrevs;
          hwrev = CSR_READ_4(sc, RL_TXCFG);
          switch (hwrev & 0x70000000) {
          case 0x00000000:
          case 0x10000000:
                  device_printf(dev, "Chip rev. 0x%08x\n", hwrev & 0xfc800000);
                  hwrev &= (RL_TXCFG_HWREV | 0x80000000);
                  break;
          default:
                  device_printf(dev, "Chip rev. 0x%08x\n", hwrev & 0x7c800000);
                  sc->rl_macrev = hwrev & 0x00700000;
                  hwrev &= RL_TXCFG_HWREV;
                  break;
          }
          device_printf(dev, "MAC rev. 0x%08x\n", sc->rl_macrev);
          while (hw_rev->rl_desc != NULL) {
                  if (hw_rev->rl_rev == hwrev) {
                          sc->rl_type = hw_rev->rl_type;
                          sc->rl_hwrev = hw_rev;
                          break;
                  }
                  hw_rev++;
          }
          if (hw_rev->rl_desc == NULL) {
                  device_printf(dev, "Unknown H/W revision: 0x%08x\n", hwrev);
                  error = ENXIO;
                  goto fail;
          }
  
          switch (hw_rev->rl_rev) {
          case RL_HWREV_8139CPLUS:
                  sc->rl_flags |= RL_FLAG_FASTETHER | RL_FLAG_AUTOPAD;
                  break;
          case RL_HWREV_8100E:
          case RL_HWREV_8101E:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_FASTETHER;
                  break;
          case RL_HWREV_8102E:
          case RL_HWREV_8102EL:
          case RL_HWREV_8102EL_SPIN1:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PAR | RL_FLAG_DESCV2 |
                      RL_FLAG_MACSTAT | RL_FLAG_FASTETHER | RL_FLAG_CMDSTOP |
                      RL_FLAG_AUTOPAD;
                  break;
          case RL_HWREV_8103E:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PAR | RL_FLAG_DESCV2 |
                      RL_FLAG_MACSTAT | RL_FLAG_FASTETHER | RL_FLAG_CMDSTOP |
                      RL_FLAG_AUTOPAD | RL_FLAG_MACSLEEP;
                  break;
          case RL_HWREV_8401E:
          case RL_HWREV_8105E:
          case RL_HWREV_8105E_SPIN1:
          case RL_HWREV_8106E:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PHYWAKE_PM |
                      RL_FLAG_PAR | RL_FLAG_DESCV2 | RL_FLAG_MACSTAT |
                      RL_FLAG_FASTETHER | RL_FLAG_CMDSTOP | RL_FLAG_AUTOPAD;
                  break;
          case RL_HWREV_8402:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PHYWAKE_PM |
                      RL_FLAG_PAR | RL_FLAG_DESCV2 | RL_FLAG_MACSTAT |
                      RL_FLAG_FASTETHER | RL_FLAG_CMDSTOP | RL_FLAG_AUTOPAD |
                      RL_FLAG_CMDSTOP_WAIT_TXQ;
                  break;
          case RL_HWREV_8168B_SPIN1:
          case RL_HWREV_8168B_SPIN2:
                  sc->rl_flags |= RL_FLAG_WOLRXENB;
                  /* FALLTHROUGH */
          case RL_HWREV_8168B_SPIN3:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_MACSTAT;
                  break;
          case RL_HWREV_8168C_SPIN2:
                  sc->rl_flags |= RL_FLAG_MACSLEEP;
                  /* FALLTHROUGH */
          case RL_HWREV_8168C:
                  if (sc->rl_macrev == 0x00200000)
                          sc->rl_flags |= RL_FLAG_MACSLEEP;
                  /* FALLTHROUGH */
          case RL_HWREV_8168CP:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PAR |
                      RL_FLAG_DESCV2 | RL_FLAG_MACSTAT | RL_FLAG_CMDSTOP |
                      RL_FLAG_AUTOPAD | RL_FLAG_JUMBOV2 | RL_FLAG_WOL_MANLINK;
                  break;
          case RL_HWREV_8168D:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PHYWAKE_PM |
                      RL_FLAG_PAR | RL_FLAG_DESCV2 | RL_FLAG_MACSTAT |
                      RL_FLAG_CMDSTOP | RL_FLAG_AUTOPAD | RL_FLAG_JUMBOV2 |
                      RL_FLAG_WOL_MANLINK;
                  break;
          case RL_HWREV_8168DP:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PAR |
                      RL_FLAG_DESCV2 | RL_FLAG_MACSTAT | RL_FLAG_AUTOPAD |
                      RL_FLAG_JUMBOV2 | RL_FLAG_WAIT_TXPOLL | RL_FLAG_WOL_MANLINK;
                  break;
          case RL_HWREV_8168E:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PHYWAKE_PM |
                      RL_FLAG_PAR | RL_FLAG_DESCV2 | RL_FLAG_MACSTAT |
                      RL_FLAG_CMDSTOP | RL_FLAG_AUTOPAD | RL_FLAG_JUMBOV2 |
                      RL_FLAG_WOL_MANLINK;
                  break;
          case RL_HWREV_8168E_VL:
          case RL_HWREV_8168F:
                  sc->rl_flags |= RL_FLAG_EARLYOFF;
                  /* FALLTHROUGH */
          case RL_HWREV_8411:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PAR |
                      RL_FLAG_DESCV2 | RL_FLAG_MACSTAT | RL_FLAG_CMDSTOP |
                      RL_FLAG_AUTOPAD | RL_FLAG_JUMBOV2 |
                      RL_FLAG_CMDSTOP_WAIT_TXQ | RL_FLAG_WOL_MANLINK;
                  break;
          case RL_HWREV_8168EP:
          case RL_HWREV_8168G:
          case RL_HWREV_8411B:
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PAR |
                      RL_FLAG_DESCV2 | RL_FLAG_MACSTAT | RL_FLAG_CMDSTOP |
                      RL_FLAG_AUTOPAD | RL_FLAG_JUMBOV2 |
                      RL_FLAG_CMDSTOP_WAIT_TXQ | RL_FLAG_WOL_MANLINK |
                      RL_FLAG_8168G_PLUS;
                  break;
          case RL_HWREV_8168GU:
          case RL_HWREV_8168H:
                  if (pci_get_device(dev) == RT_DEVICEID_8101E) {
                          /* RTL8106E(US), RTL8107E */
                          sc->rl_flags |= RL_FLAG_FASTETHER;
                  } else
                          sc->rl_flags |= RL_FLAG_JUMBOV2 | RL_FLAG_WOL_MANLINK;
  
                  sc->rl_flags |= RL_FLAG_PHYWAKE | RL_FLAG_PAR |
                      RL_FLAG_DESCV2 | RL_FLAG_MACSTAT | RL_FLAG_CMDSTOP |
                      RL_FLAG_AUTOPAD | RL_FLAG_CMDSTOP_WAIT_TXQ |
                      RL_FLAG_8168G_PLUS;
                  break;
          case RL_HWREV_8169_8110SB:
          case RL_HWREV_8169_8110SBL:
          case RL_HWREV_8169_8110SC:
          case RL_HWREV_8169_8110SCE:
                  sc->rl_flags |= RL_FLAG_PHYWAKE;
                  /* FALLTHROUGH */
          case RL_HWREV_8169:
          case RL_HWREV_8169S:
          case RL_HWREV_8110S:
                  sc->rl_flags |= RL_FLAG_MACRESET;
                  break;
          default:
                  break;
          }
  
          if (sc->rl_hwrev->rl_rev == RL_HWREV_8139CPLUS) {
                  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;
          } else {
                  sc->rl_cfg0 = RL_CFG0;
                  sc->rl_cfg1 = RL_CFG1;
                  sc->rl_cfg2 = RL_CFG2;
                  sc->rl_cfg3 = RL_CFG3;
                  sc->rl_cfg4 = RL_CFG4;
                  sc->rl_cfg5 = RL_CFG5;
          }
  
          /* Reset the adapter. */
          RL_LOCK(sc);
          re_reset(sc);
          RL_UNLOCK(sc);
  
          /* Enable PME. */
          CSR_WRITE_1(sc, RL_EECMD, RL_EE_MODE);
          cfg = CSR_READ_1(sc, sc->rl_cfg1);
          cfg |= RL_CFG1_PME;
          CSR_WRITE_1(sc, sc->rl_cfg1, cfg);
          cfg = CSR_READ_1(sc, sc->rl_cfg5);
          cfg &= RL_CFG5_PME_STS;
          CSR_WRITE_1(sc, sc->rl_cfg5, cfg);
          CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
  
          if ((sc->rl_flags & RL_FLAG_PAR) != 0) {
                  /*
                   * XXX Should have a better way to extract station
                   * address from EEPROM.
                   */
                  for (i = 0; i < ETHER_ADDR_LEN; i++)
                          eaddr[i] = CSR_READ_1(sc, RL_IDR0 + i);
          } else {
                  sc->rl_eewidth = RL_9356_ADDR_LEN;
                  re_read_eeprom(sc, (caddr_t)&re_did, 0, 1);
                  if (re_did != 0x8129)
                          sc->rl_eewidth = RL_9346_ADDR_LEN;
  
                  /*
                   * Get station address from the EEPROM.
                   */
                  re_read_eeprom(sc, (caddr_t)as, RL_EE_EADDR, 3);
                  for (i = 0; i < ETHER_ADDR_LEN / 2; i++)
                          as[i] = le16toh(as[i]);
                  bcopy(as, eaddr, ETHER_ADDR_LEN);
          }
  
          if (sc->rl_type == RL_8169) {
                  /* Set RX length mask and number of descriptors. */
                  sc->rl_rxlenmask = RL_RDESC_STAT_GFRAGLEN;
                  sc->rl_txstart = RL_GTXSTART;
                  sc->rl_ldata.rl_tx_desc_cnt = RL_8169_TX_DESC_CNT;
                  sc->rl_ldata.rl_rx_desc_cnt = RL_8169_RX_DESC_CNT;
          } else {
                  /* Set RX length mask and number of descriptors. */
                  sc->rl_rxlenmask = RL_RDESC_STAT_FRAGLEN;
                  sc->rl_txstart = RL_TXSTART;
                  sc->rl_ldata.rl_tx_desc_cnt = RL_8139_TX_DESC_CNT;
                  sc->rl_ldata.rl_rx_desc_cnt = RL_8139_RX_DESC_CNT;
          }
  
          error = re_allocmem(dev, sc);
          if (error)
                  goto fail;
          re_add_sysctls(sc);
  
          ifp = sc->rl_ifp = if_alloc(IFT_ETHER);
          if (ifp == NULL) {
                  device_printf(dev, "can not if_alloc()\n");
                  error = ENOSPC;
                  goto fail;
          }
  
          /* Take controller out of deep sleep mode. */
          if ((sc->rl_flags & RL_FLAG_MACSLEEP) != 0) {
                  if ((CSR_READ_1(sc, RL_MACDBG) & 0x80) == 0x80)
                          CSR_WRITE_1(sc, RL_GPIO,
                              CSR_READ_1(sc, RL_GPIO) | 0x01);
                  else
                          CSR_WRITE_1(sc, RL_GPIO,
                              CSR_READ_1(sc, RL_GPIO) & ~0x01);
          }
  
          /* Take PHY out of power down mode. */
          if ((sc->rl_flags & RL_FLAG_PHYWAKE_PM) != 0) {
                  CSR_WRITE_1(sc, RL_PMCH, CSR_READ_1(sc, RL_PMCH) | 0x80);
                  if (hw_rev->rl_rev == RL_HWREV_8401E)
                          CSR_WRITE_1(sc, 0xD1, CSR_READ_1(sc, 0xD1) & ~0x08);
          }
          if ((sc->rl_flags & RL_FLAG_PHYWAKE) != 0) {
                  re_gmii_writereg(dev, 1, 0x1f, 0);
                  re_gmii_writereg(dev, 1, 0x0e, 0);
          }
  
          ifp->if_softc = sc;
          if_initname(ifp, device_get_name(dev), device_get_unit(dev));
          ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
          ifp->if_ioctl = re_ioctl;
          ifp->if_start = re_start;
          /*
           * RTL8168/8111C generates wrong IP checksummed frame if the
           * packet has IP options so disable TX checksum offloading.
           */
          if (sc->rl_hwrev->rl_rev == RL_HWREV_8168C ||
              sc->rl_hwrev->rl_rev == RL_HWREV_8168C_SPIN2 ||
              sc->rl_hwrev->rl_rev == RL_HWREV_8168CP) {
                  ifp->if_hwassist = 0;
                  ifp->if_capabilities = IFCAP_RXCSUM | IFCAP_TSO4;
          } else {
                  ifp->if_hwassist = CSUM_IP | CSUM_TCP | CSUM_UDP;
                  ifp->if_capabilities = IFCAP_HWCSUM | IFCAP_TSO4;
          }
          ifp->if_hwassist |= CSUM_TSO;
          ifp->if_capenable = ifp->if_capabilities;
          ifp->if_init = re_init;
          IFQ_SET_MAXLEN(&ifp->if_snd, RL_IFQ_MAXLEN);
          ifp->if_snd.ifq_drv_maxlen = RL_IFQ_MAXLEN;
          IFQ_SET_READY(&ifp->if_snd);
  
          NET_TASK_INIT(&sc->rl_inttask, 0, re_int_task, sc);
  
  #define RE_PHYAD_INTERNAL        0
  
          /* Do MII setup. */
          phy = RE_PHYAD_INTERNAL;
          if (sc->rl_type == RL_8169)
                  phy = 1;
          capmask = BMSR_DEFCAPMASK;
          if ((sc->rl_flags & RL_FLAG_FASTETHER) != 0)
                   capmask &= ~BMSR_EXTSTAT;
          error = mii_attach(dev, &sc->rl_miibus, ifp, re_ifmedia_upd,
              re_ifmedia_sts, capmask, phy, MII_OFFSET_ANY, MIIF_DOPAUSE);
          if (error != 0) {
                  device_printf(dev, "attaching PHYs failed\n");
                  goto fail;
          }
  
          /*
           * Call MI attach routine.
           */
          ether_ifattach(ifp, eaddr);
  
          /* VLAN capability setup */
          ifp->if_capabilities |= IFCAP_VLAN_MTU | IFCAP_VLAN_HWTAGGING;
          if (ifp->if_capabilities & IFCAP_HWCSUM)
                  ifp->if_capabilities |= IFCAP_VLAN_HWCSUM;
          /* Enable WOL if PM is supported. */
          if (pci_find_cap(sc->rl_dev, PCIY_PMG, &reg) == 0)
                  ifp->if_capabilities |= IFCAP_WOL;
          ifp->if_capenable = ifp->if_capabilities;
          ifp->if_capenable &= ~(IFCAP_WOL_UCAST | IFCAP_WOL_MCAST);
          /*
           * Don't enable TSO by default.  It is known to generate
           * corrupted TCP segments(bad TCP options) under certain
           * circumstances.
           */
          ifp->if_hwassist &= ~CSUM_TSO;
          ifp->if_capenable &= ~(IFCAP_TSO4 | IFCAP_VLAN_HWTSO);
  #ifdef DEVICE_POLLING
          ifp->if_capabilities |= IFCAP_POLLING;
  #endif
          /*
           * Tell the upper layer(s) we support long frames.
           * Must appear after the call to ether_ifattach() because
           * ether_ifattach() sets ifi_hdrlen to the default value.
           */
          ifp->if_hdrlen = sizeof(struct ether_vlan_header);
  
  #ifdef DEV_NETMAP
          re_netmap_attach(sc);
  #endif /* DEV_NETMAP */
  
  #ifdef RE_DIAG
          /*
           * Perform hardware diagnostic on the original RTL8169.
           * Some 32-bit cards were incorrectly wired and would
           * malfunction if plugged into a 64-bit slot.
           */
          if (hwrev == RL_HWREV_8169) {
                  error = re_diag(sc);
                  if (error) {
                          device_printf(dev,
                          "attach aborted due to hardware diag failure\n");
                          ether_ifdetach(ifp);
                          goto fail;
                  }
          }
  #endif
  
  #ifdef RE_TX_MODERATION
          intr_filter = 1;
  #endif
          /* Hook interrupt last to avoid having to lock softc */
          if ((sc->rl_flags & (RL_FLAG_MSI | RL_FLAG_MSIX)) != 0 &&
              intr_filter == 0) {
                  error = bus_setup_intr(dev, sc->rl_irq[0],
                      INTR_TYPE_NET | INTR_MPSAFE, NULL, re_intr_msi, sc,
                      &sc->rl_intrhand[0]);
          } else {
                  error = bus_setup_intr(dev, sc->rl_irq[0],
                      INTR_TYPE_NET | INTR_MPSAFE, re_intr, NULL, sc,
                      &sc->rl_intrhand[0]);
          }
          if (error) {
                  device_printf(dev, "couldn't set up irq\n");
                  ether_ifdetach(ifp);
                  goto fail;
          }
  
          DEBUGNET_SET(ifp, re);
  
  fail:
          if (error)
                  re_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
  re_detach(device_t dev)
  {
          struct rl_softc         *sc;
          struct ifnet            *ifp;
          int                     i, rid;
  
          sc = device_get_softc(dev);
          ifp = sc->rl_ifp;
          KASSERT(mtx_initialized(&sc->rl_mtx), ("re mutex not initialized"));
  
          /* These should only be active if attach succeeded */
          if (device_is_attached(dev)) {
  #ifdef DEVICE_POLLING
                  if (ifp->if_capenable & IFCAP_POLLING)
                          ether_poll_deregister(ifp);
  #endif
                  RL_LOCK(sc);
  #if 0
                  sc->suspended = 1;
  #endif
                  re_stop(sc);
                  RL_UNLOCK(sc);
                  callout_drain(&sc->rl_stat_callout);
                  taskqueue_drain(taskqueue_fast, &sc->rl_inttask);
                  /*
                   * Force off the IFF_UP flag here, in case someone
                   * still had a BPF descriptor attached to this
                   * interface. If they do, ether_ifdetach() will cause
                   * the BPF code to try and clear the promisc mode
                   * flag, which will bubble down to re_ioctl(),
                   * which will try to call re_init() again. This will
                   * turn the NIC back on and restart the MII ticker,
                   * which will panic the system when the kernel tries
                   * to invoke the re_tick() function that isn't there
                   * anymore.
                   */
                  ifp->if_flags &= ~IFF_UP;
                  ether_ifdetach(ifp);
          }
          if (sc->rl_miibus)
                  device_delete_child(dev, sc->rl_miibus);
          bus_generic_detach(dev);
  
          /*
           * The rest is resource deallocation, so we should already be
           * stopped here.
           */
  
          if (sc->rl_intrhand[0] != NULL) {
                  bus_teardown_intr(dev, sc->rl_irq[0], sc->rl_intrhand[0]);
                  sc->rl_intrhand[0] = NULL;
          }
          if (ifp != NULL) {
  #ifdef DEV_NETMAP
                  netmap_detach(ifp);
  #endif /* DEV_NETMAP */
                  if_free(ifp);
          }
          if ((sc->rl_flags & (RL_FLAG_MSI | RL_FLAG_MSIX)) == 0)
                  rid = 0;
          else
                  rid = 1;
          if (sc->rl_irq[0] != NULL) {
                  bus_release_resource(dev, SYS_RES_IRQ, rid, sc->rl_irq[0]);
                  sc->rl_irq[0] = NULL;
          }
          if ((sc->rl_flags & (RL_FLAG_MSI | RL_FLAG_MSIX)) != 0)
                  pci_release_msi(dev);
          if (sc->rl_res_pba) {
                  rid = PCIR_BAR(4);
                  bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->rl_res_pba);
          }
          if (sc->rl_res)
                  bus_release_resource(dev, sc->rl_res_type, sc->rl_res_id,
                      sc->rl_res);
  
          /* Unload and free the RX DMA ring memory and map */
  
          if (sc->rl_ldata.rl_rx_list_tag) {
                  if (sc->rl_ldata.rl_rx_list_addr)
                          bus_dmamap_unload(sc->rl_ldata.rl_rx_list_tag,
                              sc->rl_ldata.rl_rx_list_map);
                  if (sc->rl_ldata.rl_rx_list)
                          bus_dmamem_free(sc->rl_ldata.rl_rx_list_tag,
                              sc->rl_ldata.rl_rx_list,
                              sc->rl_ldata.rl_rx_list_map);
                  bus_dma_tag_destroy(sc->rl_ldata.rl_rx_list_tag);
          }
  
          /* Unload and free the TX DMA ring memory and map */
  
          if (sc->rl_ldata.rl_tx_list_tag) {
                  if (sc->rl_ldata.rl_tx_list_addr)
                          bus_dmamap_unload(sc->rl_ldata.rl_tx_list_tag,
                              sc->rl_ldata.rl_tx_list_map);
                  if (sc->rl_ldata.rl_tx_list)
                          bus_dmamem_free(sc->rl_ldata.rl_tx_list_tag,
                              sc->rl_ldata.rl_tx_list,
                              sc->rl_ldata.rl_tx_list_map);
                  bus_dma_tag_destroy(sc->rl_ldata.rl_tx_list_tag);
          }
  
          /* Destroy all the RX and TX buffer maps */
  
          if (sc->rl_ldata.rl_tx_mtag) {
                  for (i = 0; i < sc->rl_ldata.rl_tx_desc_cnt; i++) {
                          if (sc->rl_ldata.rl_tx_desc[i].tx_dmamap)
                                  bus_dmamap_destroy(sc->rl_ldata.rl_tx_mtag,
                                      sc->rl_ldata.rl_tx_desc[i].tx_dmamap);
                  }
                  bus_dma_tag_destroy(sc->rl_ldata.rl_tx_mtag);
          }
          if (sc->rl_ldata.rl_rx_mtag) {
                  for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                          if (sc->rl_ldata.rl_rx_desc[i].rx_dmamap)
                                  bus_dmamap_destroy(sc->rl_ldata.rl_rx_mtag,
                                      sc->rl_ldata.rl_rx_desc[i].rx_dmamap);
                  }
                  if (sc->rl_ldata.rl_rx_sparemap)
                          bus_dmamap_destroy(sc->rl_ldata.rl_rx_mtag,
                              sc->rl_ldata.rl_rx_sparemap);
                  bus_dma_tag_destroy(sc->rl_ldata.rl_rx_mtag);
          }
          if (sc->rl_ldata.rl_jrx_mtag) {
                  for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                          if (sc->rl_ldata.rl_jrx_desc[i].rx_dmamap)
                                  bus_dmamap_destroy(sc->rl_ldata.rl_jrx_mtag,
                                      sc->rl_ldata.rl_jrx_desc[i].rx_dmamap);
                  }
                  if (sc->rl_ldata.rl_jrx_sparemap)
                          bus_dmamap_destroy(sc->rl_ldata.rl_jrx_mtag,
                              sc->rl_ldata.rl_jrx_sparemap);
                  bus_dma_tag_destroy(sc->rl_ldata.rl_jrx_mtag);
          }
          /* Unload and free the stats buffer and map */
  
          if (sc->rl_ldata.rl_stag) {
                  if (sc->rl_ldata.rl_stats_addr)
                          bus_dmamap_unload(sc->rl_ldata.rl_stag,
                              sc->rl_ldata.rl_smap);
                  if (sc->rl_ldata.rl_stats)
                          bus_dmamem_free(sc->rl_ldata.rl_stag,
                              sc->rl_ldata.rl_stats, sc->rl_ldata.rl_smap);
                  bus_dma_tag_destroy(sc->rl_ldata.rl_stag);
          }
  
          if (sc->rl_parent_tag)
                  bus_dma_tag_destroy(sc->rl_parent_tag);
  
          mtx_destroy(&sc->rl_mtx);
  
          return (0);
  }
  
  static __inline void
  re_discard_rxbuf(struct rl_softc *sc, int idx)
  {
          struct rl_desc          *desc;
          struct rl_rxdesc        *rxd;
          uint32_t                cmdstat;
  
          if (sc->rl_ifp->if_mtu > RL_MTU &&
              (sc->rl_flags & RL_FLAG_JUMBOV2) != 0)
                  rxd = &sc->rl_ldata.rl_jrx_desc[idx];
          else
                  rxd = &sc->rl_ldata.rl_rx_desc[idx];
          desc = &sc->rl_ldata.rl_rx_list[idx];
          desc->rl_vlanctl = 0;
          cmdstat = rxd->rx_size;
          if (idx == sc->rl_ldata.rl_rx_desc_cnt - 1)
                  cmdstat |= RL_RDESC_CMD_EOR;
          desc->rl_cmdstat = htole32(cmdstat | RL_RDESC_CMD_OWN);
  }
  
  static int
  re_newbuf(struct rl_softc *sc, int idx)
  {
          struct mbuf             *m;
          struct rl_rxdesc        *rxd;
          bus_dma_segment_t       segs[1];
          bus_dmamap_t            map;
          struct rl_desc          *desc;
          uint32_t                cmdstat;
          int                     error, nsegs;
  
          m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
          if (m == NULL)
                  return (ENOBUFS);
  
          m->m_len = m->m_pkthdr.len = MCLBYTES;
  #ifdef RE_FIXUP_RX
          /*
           * This is part of an evil trick to deal with non-x86 platforms.
           * The RealTek chip requires RX buffers to be aligned on 64-bit
           * boundaries, but that will hose non-x86 machines. To get around
           * this, we leave some empty space at the start of each buffer
           * and for non-x86 hosts, we copy the buffer back six bytes
           * to achieve word alignment. This is slightly more efficient
           * than allocating a new buffer, copying the contents, and
           * discarding the old buffer.
           */
          m_adj(m, RE_ETHER_ALIGN);
  #endif
          error = bus_dmamap_load_mbuf_sg(sc->rl_ldata.rl_rx_mtag,
              sc->rl_ldata.rl_rx_sparemap, m, segs, &nsegs, BUS_DMA_NOWAIT);
          if (error != 0) {
                  m_freem(m);
                  return (ENOBUFS);
          }
          KASSERT(nsegs == 1, ("%s: %d segment returned!", __func__, nsegs));
  
          rxd = &sc->rl_ldata.rl_rx_desc[idx];
          if (rxd->rx_m != NULL) {
                  bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag, rxd->rx_dmamap,
                      BUS_DMASYNC_POSTREAD);
                  bus_dmamap_unload(sc->rl_ldata.rl_rx_mtag, rxd->rx_dmamap);
          }
  
          rxd->rx_m = m;
          map = rxd->rx_dmamap;
          rxd->rx_dmamap = sc->rl_ldata.rl_rx_sparemap;
          rxd->rx_size = segs[0].ds_len;
          sc->rl_ldata.rl_rx_sparemap = map;
          bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag, rxd->rx_dmamap,
              BUS_DMASYNC_PREREAD);
  
          desc = &sc->rl_ldata.rl_rx_list[idx];
          desc->rl_vlanctl = 0;
          desc->rl_bufaddr_lo = htole32(RL_ADDR_LO(segs[0].ds_addr));
          desc->rl_bufaddr_hi = htole32(RL_ADDR_HI(segs[0].ds_addr));
          cmdstat = segs[0].ds_len;
          if (idx == sc->rl_ldata.rl_rx_desc_cnt - 1)
                  cmdstat |= RL_RDESC_CMD_EOR;
          desc->rl_cmdstat = htole32(cmdstat | RL_RDESC_CMD_OWN);
  
          return (0);
  }
  
  static int
  re_jumbo_newbuf(struct rl_softc *sc, int idx)
  {
          struct mbuf             *m;
          struct rl_rxdesc        *rxd;
          bus_dma_segment_t       segs[1];
          bus_dmamap_t            map;
          struct rl_desc          *desc;
          uint32_t                cmdstat;
          int                     error, nsegs;
  
          m = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUM9BYTES);
          if (m == NULL)
                  return (ENOBUFS);
          m->m_len = m->m_pkthdr.len = MJUM9BYTES;
  #ifdef RE_FIXUP_RX
          m_adj(m, RE_ETHER_ALIGN);
  #endif
          error = bus_dmamap_load_mbuf_sg(sc->rl_ldata.rl_jrx_mtag,
              sc->rl_ldata.rl_jrx_sparemap, m, segs, &nsegs, BUS_DMA_NOWAIT);
          if (error != 0) {
                  m_freem(m);
                  return (ENOBUFS);
          }
          KASSERT(nsegs == 1, ("%s: %d segment returned!", __func__, nsegs));
  
          rxd = &sc->rl_ldata.rl_jrx_desc[idx];
          if (rxd->rx_m != NULL) {
                  bus_dmamap_sync(sc->rl_ldata.rl_jrx_mtag, rxd->rx_dmamap,
                      BUS_DMASYNC_POSTREAD);
                  bus_dmamap_unload(sc->rl_ldata.rl_jrx_mtag, rxd->rx_dmamap);
          }
  
          rxd->rx_m = m;
          map = rxd->rx_dmamap;
          rxd->rx_dmamap = sc->rl_ldata.rl_jrx_sparemap;
          rxd->rx_size = segs[0].ds_len;
          sc->rl_ldata.rl_jrx_sparemap = map;
          bus_dmamap_sync(sc->rl_ldata.rl_jrx_mtag, rxd->rx_dmamap,
              BUS_DMASYNC_PREREAD);
  
          desc = &sc->rl_ldata.rl_rx_list[idx];
          desc->rl_vlanctl = 0;
          desc->rl_bufaddr_lo = htole32(RL_ADDR_LO(segs[0].ds_addr));
          desc->rl_bufaddr_hi = htole32(RL_ADDR_HI(segs[0].ds_addr));
          cmdstat = segs[0].ds_len;
          if (idx == sc->rl_ldata.rl_rx_desc_cnt - 1)
                  cmdstat |= RL_RDESC_CMD_EOR;
          desc->rl_cmdstat = htole32(cmdstat | RL_RDESC_CMD_OWN);
  
          return (0);
  }
  
  #ifdef RE_FIXUP_RX
  static __inline void
  re_fixup_rx(struct mbuf *m)
  {
          int                     i;
          uint16_t                *src, *dst;
  
          src = mtod(m, uint16_t *);
          dst = src - (RE_ETHER_ALIGN - ETHER_ALIGN) / sizeof *src;
  
          for (i = 0; i < (m->m_len / sizeof(uint16_t) + 1); i++)
                  *dst++ = *src++;
  
          m->m_data -= RE_ETHER_ALIGN - ETHER_ALIGN;
  }
  #endif
  
  static int
  re_tx_list_init(struct rl_softc *sc)
  {
          struct rl_desc          *desc;
          int                     i;
  
          RL_LOCK_ASSERT(sc);
  
          bzero(sc->rl_ldata.rl_tx_list,
              sc->rl_ldata.rl_tx_desc_cnt * sizeof(struct rl_desc));
          for (i = 0; i < sc->rl_ldata.rl_tx_desc_cnt; i++)
                  sc->rl_ldata.rl_tx_desc[i].tx_m = NULL;
  #ifdef DEV_NETMAP
          re_netmap_tx_init(sc);
  #endif /* DEV_NETMAP */
          /* Set EOR. */
          desc = &sc->rl_ldata.rl_tx_list[sc->rl_ldata.rl_tx_desc_cnt - 1];
          desc->rl_cmdstat |= htole32(RL_TDESC_CMD_EOR);
  
          bus_dmamap_sync(sc->rl_ldata.rl_tx_list_tag,
              sc->rl_ldata.rl_tx_list_map,
              BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
  
          sc->rl_ldata.rl_tx_prodidx = 0;
          sc->rl_ldata.rl_tx_considx = 0;
          sc->rl_ldata.rl_tx_free = sc->rl_ldata.rl_tx_desc_cnt;
  
          return (0);
  }
  
  static int
  re_rx_list_init(struct rl_softc *sc)
  {
          int                     error, i;
  
          bzero(sc->rl_ldata.rl_rx_list,
              sc->rl_ldata.rl_rx_desc_cnt * sizeof(struct rl_desc));
          for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                  sc->rl_ldata.rl_rx_desc[i].rx_m = NULL;
                  if ((error = re_newbuf(sc, i)) != 0)
                          return (error);
          }
  #ifdef DEV_NETMAP
          re_netmap_rx_init(sc);
  #endif /* DEV_NETMAP */
  
          /* Flush the RX descriptors */
  
          bus_dmamap_sync(sc->rl_ldata.rl_rx_list_tag,
              sc->rl_ldata.rl_rx_list_map,
              BUS_DMASYNC_PREWRITE|BUS_DMASYNC_PREREAD);
  
          sc->rl_ldata.rl_rx_prodidx = 0;
          sc->rl_head = sc->rl_tail = NULL;
          sc->rl_int_rx_act = 0;
  
          return (0);
  }
  
  static int
  re_jrx_list_init(struct rl_softc *sc)
  {
          int                     error, i;
  
          bzero(sc->rl_ldata.rl_rx_list,
              sc->rl_ldata.rl_rx_desc_cnt * sizeof(struct rl_desc));
          for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                  sc->rl_ldata.rl_jrx_desc[i].rx_m = NULL;
                  if ((error = re_jumbo_newbuf(sc, i)) != 0)
                          return (error);
          }
  
          bus_dmamap_sync(sc->rl_ldata.rl_rx_list_tag,
              sc->rl_ldata.rl_rx_list_map,
              BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
  
          sc->rl_ldata.rl_rx_prodidx = 0;
          sc->rl_head = sc->rl_tail = NULL;
          sc->rl_int_rx_act = 0;
  
          return (0);
  }
  
  /*
   * RX handler for C+ and 8169. For the gigE chips, we support
   * the reception of jumbo frames that have been fragmented
   * across multiple 2K mbuf cluster buffers.
   */
  static int
  re_rxeof(struct rl_softc *sc, int *rx_npktsp)
  {
          struct mbuf             *m;
          struct ifnet            *ifp;
          int                     i, rxerr, total_len;
          struct rl_desc          *cur_rx;
          u_int32_t               rxstat, rxvlan;
          int                     jumbo, maxpkt = 16, rx_npkts = 0;
  
          RL_LOCK_ASSERT(sc);
  
          ifp = sc->rl_ifp;
  #ifdef DEV_NETMAP
          if (netmap_rx_irq(ifp, 0, &rx_npkts))
                  return 0;
  #endif /* DEV_NETMAP */
          if (ifp->if_mtu > RL_MTU && (sc->rl_flags & RL_FLAG_JUMBOV2) != 0)
                  jumbo = 1;
          else
                  jumbo = 0;
  
          /* Invalidate the descriptor memory */
  
          bus_dmamap_sync(sc->rl_ldata.rl_rx_list_tag,
              sc->rl_ldata.rl_rx_list_map,
              BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
  
          for (i = sc->rl_ldata.rl_rx_prodidx; maxpkt > 0;
              i = RL_RX_DESC_NXT(sc, i)) {
                  if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
                          break;
                  cur_rx = &sc->rl_ldata.rl_rx_list[i];
                  rxstat = le32toh(cur_rx->rl_cmdstat);
                  if ((rxstat & RL_RDESC_STAT_OWN) != 0)
                          break;
                  total_len = rxstat & sc->rl_rxlenmask;
                  rxvlan = le32toh(cur_rx->rl_vlanctl);
                  if (jumbo != 0)
                          m = sc->rl_ldata.rl_jrx_desc[i].rx_m;
                  else
                          m = sc->rl_ldata.rl_rx_desc[i].rx_m;
  
                  if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0 &&
                      (rxstat & (RL_RDESC_STAT_SOF | RL_RDESC_STAT_EOF)) !=
                      (RL_RDESC_STAT_SOF | RL_RDESC_STAT_EOF)) {
                          /*
                           * RTL8168C or later controllers do not
                           * support multi-fragment packet.
                           */
                          re_discard_rxbuf(sc, i);
                          continue;
                  } else if ((rxstat & RL_RDESC_STAT_EOF) == 0) {
                          if (re_newbuf(sc, i) != 0) {
                                  /*
                                   * If this is part of a multi-fragment packet,
                                   * discard all the pieces.
                                   */
                                  if (sc->rl_head != NULL) {
                                          m_freem(sc->rl_head);
                                          sc->rl_head = sc->rl_tail = NULL;
                                  }
                                  re_discard_rxbuf(sc, i);
                                  continue;
                          }
                          m->m_len = RE_RX_DESC_BUFLEN;
                          if (sc->rl_head == NULL)
                                  sc->rl_head = sc->rl_tail = m;
                          else {
                                  m->m_flags &= ~M_PKTHDR;
                                  sc->rl_tail->m_next = m;
                                  sc->rl_tail = m;
                          }
                          continue;
                  }
  
                  /*
                   * NOTE: for the 8139C+, the frame length field
                   * is always 12 bits in size, but for the gigE chips,
                   * it is 13 bits (since the max RX frame length is 16K).
                   * Unfortunately, all 32 bits in the status word
                   * were already used, so to make room for the extra
                   * length bit, RealTek took out the 'frame alignment
                   * error' bit and shifted the other status bits
                   * over one slot. The OWN, EOR, FS and LS bits are
                   * still in the same places. We have already extracted
                   * the frame length and checked the OWN bit, so rather
                   * than using an alternate bit mapping, we shift the
                   * status bits one space to the right so we can evaluate
                   * them using the 8169 status as though it was in the
                   * same format as that of the 8139C+.
                   */
                  if (sc->rl_type == RL_8169)
                          rxstat >>= 1;
  
                  /*
                   * if total_len > 2^13-1, both _RXERRSUM and _GIANT will be
                   * set, but if CRC is clear, it will still be a valid frame.
                   */
                  if ((rxstat & RL_RDESC_STAT_RXERRSUM) != 0) {
                          rxerr = 1;
                          if ((sc->rl_flags & RL_FLAG_JUMBOV2) == 0 &&
                              total_len > 8191 &&
                              (rxstat & RL_RDESC_STAT_ERRS) == RL_RDESC_STAT_GIANT)
                                  rxerr = 0;
                          if (rxerr != 0) {
                                  if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
                                  /*
                                   * If this is part of a multi-fragment packet,
                                   * discard all the pieces.
                                   */
                                  if (sc->rl_head != NULL) {
                                          m_freem(sc->rl_head);
                                          sc->rl_head = sc->rl_tail = NULL;
                                  }
                                  re_discard_rxbuf(sc, i);
                                  continue;
                          }
                  }
  
                  /*
                   * If allocating a replacement mbuf fails,
                   * reload the current one.
                   */
                  if (jumbo != 0)
                          rxerr = re_jumbo_newbuf(sc, i);
                  else
                          rxerr = re_newbuf(sc, i);
                  if (rxerr != 0) {
                          if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
                          if (sc->rl_head != NULL) {
                                  m_freem(sc->rl_head);
                                  sc->rl_head = sc->rl_tail = NULL;
                          }
                          re_discard_rxbuf(sc, i);
                          continue;
                  }
  
                  if (sc->rl_head != NULL) {
                          if (jumbo != 0)
                                  m->m_len = total_len;
                          else {
                                  m->m_len = total_len % RE_RX_DESC_BUFLEN;
                                  if (m->m_len == 0)
                                          m->m_len = RE_RX_DESC_BUFLEN;
                          }
                          /*
                           * Special case: if there's 4 bytes or less
                           * in this buffer, the mbuf can be discarded:
                           * the last 4 bytes is the CRC, which we don't
                           * care about anyway.
                           */
                          if (m->m_len <= ETHER_CRC_LEN) {
                                  sc->rl_tail->m_len -=
                                      (ETHER_CRC_LEN - m->m_len);
                                  m_freem(m);
                          } else {
                                  m->m_len -= ETHER_CRC_LEN;
                                  m->m_flags &= ~M_PKTHDR;
                                  sc->rl_tail->m_next = m;
                          }
                          m = sc->rl_head;
                          sc->rl_head = sc->rl_tail = NULL;
                          m->m_pkthdr.len = total_len - ETHER_CRC_LEN;
                  } else
                          m->m_pkthdr.len = m->m_len =
                              (total_len - ETHER_CRC_LEN);
  
  #ifdef RE_FIXUP_RX
                  re_fixup_rx(m);
  #endif
                  if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
                  m->m_pkthdr.rcvif = ifp;
  
                  /* Do RX checksumming if enabled */
  
                  if (ifp->if_capenable & IFCAP_RXCSUM) {
                          if ((sc->rl_flags & RL_FLAG_DESCV2) == 0) {
                                  /* Check IP header checksum */
                                  if (rxstat & RL_RDESC_STAT_PROTOID)
                                          m->m_pkthdr.csum_flags |=
                                              CSUM_IP_CHECKED;
                                  if (!(rxstat & RL_RDESC_STAT_IPSUMBAD))
                                          m->m_pkthdr.csum_flags |=
                                              CSUM_IP_VALID;
  
                                  /* Check TCP/UDP checksum */
                                  if ((RL_TCPPKT(rxstat) &&
                                      !(rxstat & RL_RDESC_STAT_TCPSUMBAD)) ||
                                      (RL_UDPPKT(rxstat) &&
                                       !(rxstat & RL_RDESC_STAT_UDPSUMBAD))) {
                                          m->m_pkthdr.csum_flags |=
                                                  CSUM_DATA_VALID|CSUM_PSEUDO_HDR;
                                          m->m_pkthdr.csum_data = 0xffff;
                                  }
                          } else {
                                  /*
                                   * RTL8168C/RTL816CP/RTL8111C/RTL8111CP
                                   */
                                  if ((rxstat & RL_RDESC_STAT_PROTOID) &&
                                      (rxvlan & RL_RDESC_IPV4))
                                          m->m_pkthdr.csum_flags |=
                                              CSUM_IP_CHECKED;
                                  if (!(rxstat & RL_RDESC_STAT_IPSUMBAD) &&
                                      (rxvlan & RL_RDESC_IPV4))
                                          m->m_pkthdr.csum_flags |=
                                              CSUM_IP_VALID;
                                  if (((rxstat & RL_RDESC_STAT_TCP) &&
                                      !(rxstat & RL_RDESC_STAT_TCPSUMBAD)) ||
                                      ((rxstat & RL_RDESC_STAT_UDP) &&
                                      !(rxstat & RL_RDESC_STAT_UDPSUMBAD))) {
                                          m->m_pkthdr.csum_flags |=
                                                  CSUM_DATA_VALID|CSUM_PSEUDO_HDR;
                                          m->m_pkthdr.csum_data = 0xffff;
                                  }
                          }
                  }
                  maxpkt--;
                  if (rxvlan & RL_RDESC_VLANCTL_TAG) {
                          m->m_pkthdr.ether_vtag =
                              bswap16((rxvlan & RL_RDESC_VLANCTL_DATA));
                          m->m_flags |= M_VLANTAG;
                  }
                  RL_UNLOCK(sc);
                  (*ifp->if_input)(ifp, m);
                  RL_LOCK(sc);
                  rx_npkts++;
          }
  
          /* Flush the RX DMA ring */
  
          bus_dmamap_sync(sc->rl_ldata.rl_rx_list_tag,
              sc->rl_ldata.rl_rx_list_map,
              BUS_DMASYNC_PREWRITE|BUS_DMASYNC_PREREAD);
  
          sc->rl_ldata.rl_rx_prodidx = i;
  
          if (rx_npktsp != NULL)
                  *rx_npktsp = rx_npkts;
          if (maxpkt)
                  return (EAGAIN);
  
          return (0);
  }
  
  static void
  re_txeof(struct rl_softc *sc)
  {
          struct ifnet            *ifp;
          struct rl_txdesc        *txd;
          u_int32_t               txstat;
          int                     cons;
  
          cons = sc->rl_ldata.rl_tx_considx;
          if (cons == sc->rl_ldata.rl_tx_prodidx)
                  return;
  
          ifp = sc->rl_ifp;
  #ifdef DEV_NETMAP
          if (netmap_tx_irq(ifp, 0))
                  return;
  #endif /* DEV_NETMAP */
          /* Invalidate the TX descriptor list */
          bus_dmamap_sync(sc->rl_ldata.rl_tx_list_tag,
              sc->rl_ldata.rl_tx_list_map,
              BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
  
          for (; cons != sc->rl_ldata.rl_tx_prodidx;
              cons = RL_TX_DESC_NXT(sc, cons)) {
                  txstat = le32toh(sc->rl_ldata.rl_tx_list[cons].rl_cmdstat);
                  if (txstat & RL_TDESC_STAT_OWN)
                          break;
                  /*
                   * We only stash mbufs in the last descriptor
                   * in a fragment chain, which also happens to
                   * be the only place where the TX status bits
                   * are valid.
                   */
                  if (txstat & RL_TDESC_CMD_EOF) {
                          txd = &sc->rl_ldata.rl_tx_desc[cons];
                          bus_dmamap_sync(sc->rl_ldata.rl_tx_mtag,
                              txd->tx_dmamap, BUS_DMASYNC_POSTWRITE);
                          bus_dmamap_unload(sc->rl_ldata.rl_tx_mtag,
                              txd->tx_dmamap);
                          KASSERT(txd->tx_m != NULL,
                              ("%s: freeing NULL mbufs!", __func__));
                          m_freem(txd->tx_m);
                          txd->tx_m = NULL;
                          if (txstat & (RL_TDESC_STAT_EXCESSCOL|
                              RL_TDESC_STAT_COLCNT))
                                  if_inc_counter(ifp, IFCOUNTER_COLLISIONS, 1);
                          if (txstat & RL_TDESC_STAT_TXERRSUM)
                                  if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
                          else
                                  if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
                  }
                  sc->rl_ldata.rl_tx_free++;
                  ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
          }
          sc->rl_ldata.rl_tx_considx = cons;
  
          /* No changes made to the TX ring, so no flush needed */
  
          if (sc->rl_ldata.rl_tx_free != sc->rl_ldata.rl_tx_desc_cnt) {
  #ifdef RE_TX_MODERATION
                  /*
                   * If not all descriptors have been reaped yet, reload
                   * the timer so that we will eventually get another
                   * interrupt that will cause us to re-enter this routine.
                   * This is done in case the transmitter has gone idle.
                   */
                  CSR_WRITE_4(sc, RL_TIMERCNT, 1);
  #endif
          } else
                  sc->rl_watchdog_timer = 0;
  }
  
  static void
  re_tick(void *xsc)
  {
          struct rl_softc         *sc;
          struct mii_data         *mii;
  
          sc = xsc;
  
          RL_LOCK_ASSERT(sc);
  
          mii = device_get_softc(sc->rl_miibus);
          mii_tick(mii);
          if ((sc->rl_flags & RL_FLAG_LINK) == 0)
                  re_miibus_statchg(sc->rl_dev);
          /*
           * Reclaim transmitted frames here. Technically it is not
           * necessary to do here but it ensures periodic reclamation
           * regardless of Tx completion interrupt which seems to be
           * lost on PCIe based controllers under certain situations.
           */
          re_txeof(sc);
          re_watchdog(sc);
          callout_reset(&sc->rl_stat_callout, hz, re_tick, sc);
  }
  
  #ifdef DEVICE_POLLING
  static int
  re_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 = re_poll_locked(ifp, cmd, count);
          RL_UNLOCK(sc);
          return (rx_npkts);
  }
  
  static int
  re_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;
          re_rxeof(sc, &rx_npkts);
          re_txeof(sc);
  
          if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
                  re_start_locked(ifp);
  
          if (cmd == POLL_AND_CHECK_STATUS) { /* also check status register */
                  u_int16_t       status;
  
                  status = CSR_READ_2(sc, RL_ISR);
                  if (status == 0xffff)
                          return (rx_npkts);
                  if (status)
                          CSR_WRITE_2(sc, RL_ISR, status);
                  if ((status & (RL_ISR_TX_OK | RL_ISR_TX_DESC_UNAVAIL)) &&
                      (sc->rl_flags & RL_FLAG_PCIE))
                          CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
  
                  /*
                   * XXX check behaviour on receiver stalls.
                   */
  
                  if (status & RL_ISR_SYSTEM_ERR) {
                          ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
                          re_init_locked(sc);
                  }
          }
          return (rx_npkts);
  }
  #endif /* DEVICE_POLLING */
  
  static int
  re_intr(void *arg)
  {
          struct rl_softc         *sc;
          uint16_t                status;
  
          sc = arg;
  
          status = CSR_READ_2(sc, RL_ISR);
          if (status == 0xFFFF || (status & RL_INTRS_CPLUS) == 0)
                  return (FILTER_STRAY);
          CSR_WRITE_2(sc, RL_IMR, 0);
  
          taskqueue_enqueue(taskqueue_fast, &sc->rl_inttask);
  
          return (FILTER_HANDLED);
  }
  
  static void
  re_int_task(void *arg, int npending)
  {
          struct rl_softc         *sc;
          struct ifnet            *ifp;
          u_int16_t               status;
          int                     rval = 0;
  
          sc = arg;
          ifp = sc->rl_ifp;
  
          RL_LOCK(sc);
  
          status = CSR_READ_2(sc, RL_ISR);
          CSR_WRITE_2(sc, RL_ISR, status);
  
          if (sc->suspended ||
              (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
                  RL_UNLOCK(sc);
                  return;
          }
  
  #ifdef DEVICE_POLLING
          if  (ifp->if_capenable & IFCAP_POLLING) {
                  RL_UNLOCK(sc);
                  return;
          }
  #endif
  
          if (status & (RL_ISR_RX_OK|RL_ISR_RX_ERR|RL_ISR_FIFO_OFLOW))
                  rval = re_rxeof(sc, NULL);
  
          /*
           * Some chips will ignore a second TX request issued
           * while an existing transmission is in progress. If
           * the transmitter goes idle but there are still
           * packets waiting to be sent, we need to restart the
           * channel here to flush them out. This only seems to
           * be required with the PCIe devices.
           */
          if ((status & (RL_ISR_TX_OK | RL_ISR_TX_DESC_UNAVAIL)) &&
              (sc->rl_flags & RL_FLAG_PCIE))
                  CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
          if (status & (
  #ifdef RE_TX_MODERATION
              RL_ISR_TIMEOUT_EXPIRED|
  #else
              RL_ISR_TX_OK|
  #endif
              RL_ISR_TX_ERR|RL_ISR_TX_DESC_UNAVAIL))
                  re_txeof(sc);
  
          if (status & RL_ISR_SYSTEM_ERR) {
                  ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
                  re_init_locked(sc);
          }
  
          if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
                  re_start_locked(ifp);
  
          RL_UNLOCK(sc);
  
          if ((CSR_READ_2(sc, RL_ISR) & RL_INTRS_CPLUS) || rval) {
                  taskqueue_enqueue(taskqueue_fast, &sc->rl_inttask);
                  return;
          }
  
          CSR_WRITE_2(sc, RL_IMR, RL_INTRS_CPLUS);
  }
  
  static void
  re_intr_msi(void *xsc)
  {
          struct rl_softc         *sc;
          struct ifnet            *ifp;
          uint16_t                intrs, status;
  
          sc = xsc;
          RL_LOCK(sc);
  
          ifp = sc->rl_ifp;
  #ifdef DEVICE_POLLING
          if (ifp->if_capenable & IFCAP_POLLING) {
                  RL_UNLOCK(sc);
                  return;
          }
  #endif
          /* Disable interrupts. */
          CSR_WRITE_2(sc, RL_IMR, 0);
          if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
                  RL_UNLOCK(sc);
                  return;
          }
  
          intrs = RL_INTRS_CPLUS;
          status = CSR_READ_2(sc, RL_ISR);
          CSR_WRITE_2(sc, RL_ISR, status);
          if (sc->rl_int_rx_act > 0) {
                  intrs &= ~(RL_ISR_RX_OK | RL_ISR_RX_ERR | RL_ISR_FIFO_OFLOW |
                      RL_ISR_RX_OVERRUN);
                  status &= ~(RL_ISR_RX_OK | RL_ISR_RX_ERR | RL_ISR_FIFO_OFLOW |
                      RL_ISR_RX_OVERRUN);
          }
  
          if (status & (RL_ISR_TIMEOUT_EXPIRED | RL_ISR_RX_OK | RL_ISR_RX_ERR |
              RL_ISR_FIFO_OFLOW | RL_ISR_RX_OVERRUN)) {
                  re_rxeof(sc, NULL);
                  if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0) {
                          if (sc->rl_int_rx_mod != 0 &&
                              (status & (RL_ISR_RX_OK | RL_ISR_RX_ERR |
                              RL_ISR_FIFO_OFLOW | RL_ISR_RX_OVERRUN)) != 0) {
                                  /* Rearm one-shot timer. */
                                  CSR_WRITE_4(sc, RL_TIMERCNT, 1);
                                  intrs &= ~(RL_ISR_RX_OK | RL_ISR_RX_ERR |
                                      RL_ISR_FIFO_OFLOW | RL_ISR_RX_OVERRUN);
                                  sc->rl_int_rx_act = 1;
                          } else {
                                  intrs |= RL_ISR_RX_OK | RL_ISR_RX_ERR |
                                      RL_ISR_FIFO_OFLOW | RL_ISR_RX_OVERRUN;
                                  sc->rl_int_rx_act = 0;
                          }
                  }
          }
  
          /*
           * Some chips will ignore a second TX request issued
           * while an existing transmission is in progress. If
           * the transmitter goes idle but there are still
           * packets waiting to be sent, we need to restart the
           * channel here to flush them out. This only seems to
           * be required with the PCIe devices.
           */
          if ((status & (RL_ISR_TX_OK | RL_ISR_TX_DESC_UNAVAIL)) &&
              (sc->rl_flags & RL_FLAG_PCIE))
                  CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
          if (status & (RL_ISR_TX_OK | RL_ISR_TX_ERR | RL_ISR_TX_DESC_UNAVAIL))
                  re_txeof(sc);
  
          if (status & RL_ISR_SYSTEM_ERR) {
                  ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
                  re_init_locked(sc);
          }
  
          if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0) {
                  if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
                          re_start_locked(ifp);
                  CSR_WRITE_2(sc, RL_IMR, intrs);
          }
          RL_UNLOCK(sc);
  }
  
  static int
  re_encap(struct rl_softc *sc, struct mbuf **m_head)
  {
          struct rl_txdesc        *txd, *txd_last;
          bus_dma_segment_t       segs[RL_NTXSEGS];
          bus_dmamap_t            map;
          struct mbuf             *m_new;
          struct rl_desc          *desc;
          int                     nsegs, prod;
          int                     i, error, ei, si;
          int                     padlen;
          uint32_t                cmdstat, csum_flags, vlanctl;
  
          RL_LOCK_ASSERT(sc);
          M_ASSERTPKTHDR((*m_head));
  
          /*
           * With some of the RealTek chips, using the checksum offload
           * support in conjunction with the autopadding feature results
           * in the transmission of corrupt frames. For example, if we
           * need to send a really small IP fragment that's less than 60
           * bytes in size, and IP header checksumming is enabled, the
           * resulting ethernet frame that appears on the wire will
           * have garbled payload. To work around this, if TX IP checksum
           * offload is enabled, we always manually pad short frames out
           * to the minimum ethernet frame size.
           */
          if ((sc->rl_flags & RL_FLAG_AUTOPAD) == 0 &&
              (*m_head)->m_pkthdr.len < RL_IP4CSUMTX_PADLEN &&
              ((*m_head)->m_pkthdr.csum_flags & CSUM_IP) != 0) {
                  padlen = RL_MIN_FRAMELEN - (*m_head)->m_pkthdr.len;
                  if (M_WRITABLE(*m_head) == 0) {
                          /* Get a writable copy. */
                          m_new = m_dup(*m_head, M_NOWAIT);
                          m_freem(*m_head);
                          if (m_new == NULL) {
                                  *m_head = NULL;
                                  return (ENOBUFS);
                          }
                          *m_head = m_new;
                  }
                  if ((*m_head)->m_next != NULL ||
                      M_TRAILINGSPACE(*m_head) < padlen) {
                          m_new = m_defrag(*m_head, M_NOWAIT);
                          if (m_new == NULL) {
                                  m_freem(*m_head);
                                  *m_head = NULL;
                                  return (ENOBUFS);
                          }
                  } else
                          m_new = *m_head;
  
                  /*
                   * Manually pad short frames, and zero the pad space
                   * to avoid leaking data.
                   */
                  bzero(mtod(m_new, char *) + m_new->m_pkthdr.len, padlen);
                  m_new->m_pkthdr.len += padlen;
                  m_new->m_len = m_new->m_pkthdr.len;
                  *m_head = m_new;
          }
  
          prod = sc->rl_ldata.rl_tx_prodidx;
          txd = &sc->rl_ldata.rl_tx_desc[prod];
          error = bus_dmamap_load_mbuf_sg(sc->rl_ldata.rl_tx_mtag, txd->tx_dmamap,
              *m_head, segs, &nsegs, BUS_DMA_NOWAIT);
          if (error == EFBIG) {
                  m_new = m_collapse(*m_head, M_NOWAIT, RL_NTXSEGS);
                  if (m_new == NULL) {
                          m_freem(*m_head);
                          *m_head = NULL;
                          return (ENOBUFS);
                  }
                  *m_head = m_new;
                  error = bus_dmamap_load_mbuf_sg(sc->rl_ldata.rl_tx_mtag,
                      txd->tx_dmamap, *m_head, segs, &nsegs, BUS_DMA_NOWAIT);
                  if (error != 0) {
                          m_freem(*m_head);
                          *m_head = NULL;
                          return (error);
                  }
          } else if (error != 0)
                  return (error);
          if (nsegs == 0) {
                  m_freem(*m_head);
                  *m_head = NULL;
                  return (EIO);
          }
  
          /* Check for number of available descriptors. */
          if (sc->rl_ldata.rl_tx_free - nsegs <= 1) {
                  bus_dmamap_unload(sc->rl_ldata.rl_tx_mtag, txd->tx_dmamap);
                  return (ENOBUFS);
          }
  
          bus_dmamap_sync(sc->rl_ldata.rl_tx_mtag, txd->tx_dmamap,
              BUS_DMASYNC_PREWRITE);
  
          /*
           * Set up checksum offload. Note: checksum offload bits must
           * appear in all descriptors of a multi-descriptor transmit
           * attempt. This is according to testing done with an 8169
           * chip. This is a requirement.
           */
          vlanctl = 0;
          csum_flags = 0;
          if (((*m_head)->m_pkthdr.csum_flags & CSUM_TSO) != 0) {
                  if ((sc->rl_flags & RL_FLAG_DESCV2) != 0) {
                          csum_flags |= RL_TDESC_CMD_LGSEND;
                          vlanctl |= ((uint32_t)(*m_head)->m_pkthdr.tso_segsz <<
                              RL_TDESC_CMD_MSSVALV2_SHIFT);
                  } else {
                          csum_flags |= RL_TDESC_CMD_LGSEND |
                              ((uint32_t)(*m_head)->m_pkthdr.tso_segsz <<
                              RL_TDESC_CMD_MSSVAL_SHIFT);
                  }
          } else {
                  /*
                   * Unconditionally enable IP checksum if TCP or UDP
                   * checksum is required. Otherwise, TCP/UDP checksum
                   * doesn't make effects.
                   */
                  if (((*m_head)->m_pkthdr.csum_flags & RE_CSUM_FEATURES) != 0) {
                          if ((sc->rl_flags & RL_FLAG_DESCV2) == 0) {
                                  csum_flags |= RL_TDESC_CMD_IPCSUM;
                                  if (((*m_head)->m_pkthdr.csum_flags &
                                      CSUM_TCP) != 0)
                                          csum_flags |= RL_TDESC_CMD_TCPCSUM;
                                  if (((*m_head)->m_pkthdr.csum_flags &
                                      CSUM_UDP) != 0)
                                          csum_flags |= RL_TDESC_CMD_UDPCSUM;
                          } else {
                                  vlanctl |= RL_TDESC_CMD_IPCSUMV2;
                                  if (((*m_head)->m_pkthdr.csum_flags &
                                      CSUM_TCP) != 0)
                                          vlanctl |= RL_TDESC_CMD_TCPCSUMV2;
                                  if (((*m_head)->m_pkthdr.csum_flags &
                                      CSUM_UDP) != 0)
                                          vlanctl |= RL_TDESC_CMD_UDPCSUMV2;
                          }
                  }
          }
  
          /*
           * Set up hardware VLAN tagging. Note: vlan tag info must
           * appear in all descriptors of a multi-descriptor
           * transmission attempt.
           */
          if ((*m_head)->m_flags & M_VLANTAG)
                  vlanctl |= bswap16((*m_head)->m_pkthdr.ether_vtag) |
                      RL_TDESC_VLANCTL_TAG;
  
          si = prod;
          for (i = 0; i < nsegs; i++, prod = RL_TX_DESC_NXT(sc, prod)) {
                  desc = &sc->rl_ldata.rl_tx_list[prod];
                  desc->rl_vlanctl = htole32(vlanctl);
                  desc->rl_bufaddr_lo = htole32(RL_ADDR_LO(segs[i].ds_addr));
                  desc->rl_bufaddr_hi = htole32(RL_ADDR_HI(segs[i].ds_addr));
                  cmdstat = segs[i].ds_len;
                  if (i != 0)
                          cmdstat |= RL_TDESC_CMD_OWN;
                  if (prod == sc->rl_ldata.rl_tx_desc_cnt - 1)
                          cmdstat |= RL_TDESC_CMD_EOR;
                  desc->rl_cmdstat = htole32(cmdstat | csum_flags);
                  sc->rl_ldata.rl_tx_free--;
          }
          /* Update producer index. */
          sc->rl_ldata.rl_tx_prodidx = prod;
  
          /* Set EOF on the last descriptor. */
          ei = RL_TX_DESC_PRV(sc, prod);
          desc = &sc->rl_ldata.rl_tx_list[ei];
          desc->rl_cmdstat |= htole32(RL_TDESC_CMD_EOF);
  
          desc = &sc->rl_ldata.rl_tx_list[si];
          /* Set SOF and transfer ownership of packet to the chip. */
          desc->rl_cmdstat |= htole32(RL_TDESC_CMD_OWN | RL_TDESC_CMD_SOF);
  
          /*
           * Insure that the map for this transmission
           * is placed at the array index of the last descriptor
           * in this chain.  (Swap last and first dmamaps.)
           */
          txd_last = &sc->rl_ldata.rl_tx_desc[ei];
          map = txd->tx_dmamap;
          txd->tx_dmamap = txd_last->tx_dmamap;
          txd_last->tx_dmamap = map;
          txd_last->tx_m = *m_head;
  
          return (0);
  }
  
  static void
  re_start(struct ifnet *ifp)
  {
          struct rl_softc         *sc;
  
          sc = ifp->if_softc;
          RL_LOCK(sc);
          re_start_locked(ifp);
          RL_UNLOCK(sc);
  }
  
  /*
   * Main transmit routine for C+ and gigE NICs.
   */
  static void
  re_start_locked(struct ifnet *ifp)
  {
          struct rl_softc         *sc;
          struct mbuf             *m_head;
          int                     queued;
  
          sc = ifp->if_softc;
  
  #ifdef DEV_NETMAP
          /* XXX is this necessary ? */
          if (ifp->if_capenable & IFCAP_NETMAP) {
                  struct netmap_kring *kring = NA(ifp)->tx_rings[0];
                  if (sc->rl_ldata.rl_tx_prodidx != kring->nr_hwcur) {
                          /* kick the tx unit */
                          CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
  #ifdef RE_TX_MODERATION
                          CSR_WRITE_4(sc, RL_TIMERCNT, 1);
  #endif
                          sc->rl_watchdog_timer = 5;
                  }
                  return;
          }
  #endif /* DEV_NETMAP */
  
          if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
              IFF_DRV_RUNNING || (sc->rl_flags & RL_FLAG_LINK) == 0)
                  return;
  
          for (queued = 0; !IFQ_DRV_IS_EMPTY(&ifp->if_snd) &&
              sc->rl_ldata.rl_tx_free > 1;) {
                  IFQ_DRV_DEQUEUE(&ifp->if_snd, m_head);
                  if (m_head == NULL)
                          break;
  
                  if (re_encap(sc, &m_head) != 0) {
                          if (m_head == NULL)
                                  break;
                          IFQ_DRV_PREPEND(&ifp->if_snd, m_head);
                          ifp->if_drv_flags |= IFF_DRV_OACTIVE;
                          break;
                  }
  
                  /*
                   * If there's a BPF listener, bounce a copy of this frame
                   * to him.
                   */
                  ETHER_BPF_MTAP(ifp, m_head);
  
                  queued++;
          }
  
          if (queued == 0) {
  #ifdef RE_TX_MODERATION
                  if (sc->rl_ldata.rl_tx_free != sc->rl_ldata.rl_tx_desc_cnt)
                          CSR_WRITE_4(sc, RL_TIMERCNT, 1);
  #endif
                  return;
          }
  
          re_start_tx(sc);
  }
  
  static void
  re_start_tx(struct rl_softc *sc)
  {
  
          /* Flush the TX descriptors */
          bus_dmamap_sync(sc->rl_ldata.rl_tx_list_tag,
              sc->rl_ldata.rl_tx_list_map,
              BUS_DMASYNC_PREWRITE|BUS_DMASYNC_PREREAD);
  
          CSR_WRITE_1(sc, sc->rl_txstart, RL_TXSTART_START);
  
  #ifdef RE_TX_MODERATION
          /*
           * Use the countdown timer for interrupt moderation.
           * 'TX done' interrupts are disabled. Instead, we reset the
           * countdown timer, which will begin counting until it hits
           * the value in the TIMERINT register, and then trigger an
           * interrupt. Each time we write to the TIMERCNT register,
           * the timer count is reset to 0.
           */
          CSR_WRITE_4(sc, RL_TIMERCNT, 1);
  #endif
  
          /*
           * Set a timeout in case the chip goes out to lunch.
           */
          sc->rl_watchdog_timer = 5;
  }
  
  static void
  re_set_jumbo(struct rl_softc *sc, int jumbo)
  {
  
          if (sc->rl_hwrev->rl_rev == RL_HWREV_8168E_VL) {
                  pci_set_max_read_req(sc->rl_dev, 4096);
                  return;
          }
  
          CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_WRITECFG);
          if (jumbo != 0) {
                  CSR_WRITE_1(sc, sc->rl_cfg3, CSR_READ_1(sc, sc->rl_cfg3) |
                      RL_CFG3_JUMBO_EN0);
                  switch (sc->rl_hwrev->rl_rev) {
                  case RL_HWREV_8168DP:
                          break;
                  case RL_HWREV_8168E:
                          CSR_WRITE_1(sc, sc->rl_cfg4,
                              CSR_READ_1(sc, sc->rl_cfg4) | 0x01);
                          break;
                  default:
                          CSR_WRITE_1(sc, sc->rl_cfg4,
                              CSR_READ_1(sc, sc->rl_cfg4) | RL_CFG4_JUMBO_EN1);
                  }
          } else {
                  CSR_WRITE_1(sc, sc->rl_cfg3, CSR_READ_1(sc, sc->rl_cfg3) &
                      ~RL_CFG3_JUMBO_EN0);
                  switch (sc->rl_hwrev->rl_rev) {
                  case RL_HWREV_8168DP:
                          break;
                  case RL_HWREV_8168E:
                          CSR_WRITE_1(sc, sc->rl_cfg4,
                              CSR_READ_1(sc, sc->rl_cfg4) & ~0x01);
                          break;
                  default:
                          CSR_WRITE_1(sc, sc->rl_cfg4,
                              CSR_READ_1(sc, sc->rl_cfg4) & ~RL_CFG4_JUMBO_EN1);
                  }
          }
          CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
  
          switch (sc->rl_hwrev->rl_rev) {
          case RL_HWREV_8168DP:
                  pci_set_max_read_req(sc->rl_dev, 4096);
                  break;
          default:
                  if (jumbo != 0)
                          pci_set_max_read_req(sc->rl_dev, 512);
                  else
                          pci_set_max_read_req(sc->rl_dev, 4096);
          }
  }
  
  static void
  re_init(void *xsc)
  {
          struct rl_softc         *sc = xsc;
  
          RL_LOCK(sc);
          re_init_locked(sc);
          RL_UNLOCK(sc);
  }
  
  static void
  re_init_locked(struct rl_softc *sc)
  {
          struct ifnet            *ifp = sc->rl_ifp;
          struct mii_data         *mii;
          uint32_t                reg;
          uint16_t                cfg;
          uint32_t                idr[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.
           */
          re_stop(sc);
  
          /* Put controller into known state. */
          re_reset(sc);
  
          /*
           * For C+ mode, initialize the RX descriptors and mbufs.
           */
          if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0) {
                  if (ifp->if_mtu > RL_MTU) {
                          if (re_jrx_list_init(sc) != 0) {
                                  device_printf(sc->rl_dev,
                                      "no memory for jumbo RX buffers\n");
                                  re_stop(sc);
                                  return;
                          }
                          /* Disable checksum offloading for jumbo frames. */
                          ifp->if_capenable &= ~(IFCAP_HWCSUM | IFCAP_TSO4);
                          ifp->if_hwassist &= ~(RE_CSUM_FEATURES | CSUM_TSO);
                  } else {
                          if (re_rx_list_init(sc) != 0) {
                                  device_printf(sc->rl_dev,
                                      "no memory for RX buffers\n");
                                  re_stop(sc);
                                  return;
                          }
                  }
                  re_set_jumbo(sc, ifp->if_mtu > RL_MTU);
          } else {
                  if (re_rx_list_init(sc) != 0) {
                          device_printf(sc->rl_dev, "no memory for RX buffers\n");
                          re_stop(sc);
                          return;
                  }
                  if ((sc->rl_flags & RL_FLAG_PCIE) != 0 &&
                      pci_get_device(sc->rl_dev) != RT_DEVICEID_8101E) {
                          if (ifp->if_mtu > RL_MTU)
                                  pci_set_max_read_req(sc->rl_dev, 512);
                          else
                                  pci_set_max_read_req(sc->rl_dev, 4096);
                  }
          }
          re_tx_list_init(sc);
  
          /*
           * Enable C+ RX and TX mode, as well as VLAN stripping and
           * RX checksum offload. We must configure the C+ register
           * before all others.
           */
          cfg = RL_CPLUSCMD_PCI_MRW;
          if ((ifp->if_capenable & IFCAP_RXCSUM) != 0)
                  cfg |= RL_CPLUSCMD_RXCSUM_ENB;
          if ((ifp->if_capenable & IFCAP_VLAN_HWTAGGING) != 0)
                  cfg |= RL_CPLUSCMD_VLANSTRIP;
          if ((sc->rl_flags & RL_FLAG_MACSTAT) != 0) {
                  cfg |= RL_CPLUSCMD_MACSTAT_DIS;
                  /* XXX magic. */
                  cfg |= 0x0001;
          } else
                  cfg |= RL_CPLUSCMD_RXENB | RL_CPLUSCMD_TXENB;
          CSR_WRITE_2(sc, RL_CPLUS_CMD, cfg);
          if (sc->rl_hwrev->rl_rev == RL_HWREV_8169_8110SC ||
              sc->rl_hwrev->rl_rev == RL_HWREV_8169_8110SCE) {
                  reg = 0x000fff00;
                  if ((CSR_READ_1(sc, sc->rl_cfg2) & RL_CFG2_PCI66MHZ) != 0)
                          reg |= 0x000000ff;
                  if (sc->rl_hwrev->rl_rev == RL_HWREV_8169_8110SCE)
                          reg |= 0x00f00000;
                  CSR_WRITE_4(sc, 0x7c, reg);
                  /* Disable interrupt mitigation. */
                  CSR_WRITE_2(sc, 0xe2, 0);
          }
          /*
           * Disable TSO if interface MTU size is greater than MSS
           * allowed in controller.
           */
          if (ifp->if_mtu > RL_TSO_MTU && (ifp->if_capenable & IFCAP_TSO4) != 0) {
                  ifp->if_capenable &= ~IFCAP_TSO4;
                  ifp->if_hwassist &= ~CSUM_TSO;
          }
  
          /*
           * 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.
           */
          /* Copy MAC address on stack to align. */
          bzero(idr, sizeof(idr));
          bcopy(IF_LLADDR(ifp), idr, ETHER_ADDR_LEN);
          CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_WRITECFG);
          CSR_WRITE_4(sc, RL_IDR0, htole32(idr[0]));
          CSR_WRITE_4(sc, RL_IDR4, htole32(idr[1]));
          CSR_WRITE_1(sc, RL_EECMD, RL_EEMODE_OFF);
  
          /*
           * Load the addresses of the RX and TX lists into the chip.
           */
  
          CSR_WRITE_4(sc, RL_RXLIST_ADDR_HI,
              RL_ADDR_HI(sc->rl_ldata.rl_rx_list_addr));
          CSR_WRITE_4(sc, RL_RXLIST_ADDR_LO,
              RL_ADDR_LO(sc->rl_ldata.rl_rx_list_addr));
  
          CSR_WRITE_4(sc, RL_TXLIST_ADDR_HI,
              RL_ADDR_HI(sc->rl_ldata.rl_tx_list_addr));
          CSR_WRITE_4(sc, RL_TXLIST_ADDR_LO,
              RL_ADDR_LO(sc->rl_ldata.rl_tx_list_addr));
  
          if ((sc->rl_flags & RL_FLAG_8168G_PLUS) != 0) {
                  /* Disable RXDV gate. */
                  CSR_WRITE_4(sc, RL_MISC, CSR_READ_4(sc, RL_MISC) &
                      ~0x00080000);
          }
  
          /*
           * Enable transmit and receive for pre-RTL8168G controllers.
           * RX/TX MACs should be enabled before RX/TX configuration.
           */
          if ((sc->rl_flags & RL_FLAG_8168G_PLUS) == 0)
                  CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_TX_ENB | RL_CMD_RX_ENB);
  
          /*
           * Set the initial TX configuration.
           */
          if (sc->rl_testmode) {
                  if (sc->rl_type == RL_8169)
                          CSR_WRITE_4(sc, RL_TXCFG,
                              RL_TXCFG_CONFIG|RL_LOOPTEST_ON);
                  else
                          CSR_WRITE_4(sc, RL_TXCFG,
                              RL_TXCFG_CONFIG|RL_LOOPTEST_ON_CPLUS);
          } else
                  CSR_WRITE_4(sc, RL_TXCFG, RL_TXCFG_CONFIG);
  
          CSR_WRITE_1(sc, RL_EARLY_TX_THRESH, 16);
  
          /*
           * Set the initial RX configuration.
           */
          re_set_rxmode(sc);
  
          /* Configure interrupt moderation. */
          if (sc->rl_type == RL_8169) {
                  /* Magic from vendor. */
                  CSR_WRITE_2(sc, RL_INTRMOD, 0x5100);
          }
  
          /*
           * Enable transmit and receive for RTL8168G and later controllers.
           * RX/TX MACs should be enabled after RX/TX configuration.
           */
          if ((sc->rl_flags & RL_FLAG_8168G_PLUS) != 0)
                  CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_TX_ENB | RL_CMD_RX_ENB);
  
  #ifdef DEVICE_POLLING
          /*
           * Disable interrupts if we are polling.
           */
          if (ifp->if_capenable & IFCAP_POLLING)
                  CSR_WRITE_2(sc, RL_IMR, 0);
          else    /* otherwise ... */
  #endif
  
          /*
           * Enable interrupts.
           */
          if (sc->rl_testmode)
                  CSR_WRITE_2(sc, RL_IMR, 0);
          else
                  CSR_WRITE_2(sc, RL_IMR, RL_INTRS_CPLUS);
          CSR_WRITE_2(sc, RL_ISR, RL_INTRS_CPLUS);
  
          /* Set initial TX threshold */
          sc->rl_txthresh = RL_TX_THRESH_INIT;
  
          /* Start RX/TX process. */
          CSR_WRITE_4(sc, RL_MISSEDPKT, 0);
  
          /*
           * Initialize the timer interrupt register so that
           * a timer interrupt will be generated once the timer
           * reaches a certain number of ticks. The timer is
           * reloaded on each transmit.
           */
  #ifdef RE_TX_MODERATION
          /*
           * Use timer interrupt register to moderate TX interrupt
           * moderation, which dramatically improves TX frame rate.
           */
          if (sc->rl_type == RL_8169)
                  CSR_WRITE_4(sc, RL_TIMERINT_8169, 0x800);
          else
                  CSR_WRITE_4(sc, RL_TIMERINT, 0x400);
  #else
          /*
           * Use timer interrupt register to moderate RX interrupt
           * moderation.
           */
          if ((sc->rl_flags & (RL_FLAG_MSI | RL_FLAG_MSIX)) != 0 &&
              intr_filter == 0) {
                  if (sc->rl_type == RL_8169)
                          CSR_WRITE_4(sc, RL_TIMERINT_8169,
                              RL_USECS(sc->rl_int_rx_mod));
          } else {
                  if (sc->rl_type == RL_8169)
                          CSR_WRITE_4(sc, RL_TIMERINT_8169, RL_USECS(0));
          }
  #endif
  
          /*
           * For 8169 gigE NICs, set the max allowed RX packet
           * size so we can receive jumbo frames.
           */
          if (sc->rl_type == RL_8169) {
                  if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0) {
                          /*
                           * For controllers that use new jumbo frame scheme,
                           * set maximum size of jumbo frame depending on
                           * controller revisions.
                           */
                          if (ifp->if_mtu > RL_MTU)
                                  CSR_WRITE_2(sc, RL_MAXRXPKTLEN,
                                      sc->rl_hwrev->rl_max_mtu +
                                      ETHER_VLAN_ENCAP_LEN + ETHER_HDR_LEN +
                                      ETHER_CRC_LEN);
                          else
                                  CSR_WRITE_2(sc, RL_MAXRXPKTLEN,
                                      RE_RX_DESC_BUFLEN);
                  } else if ((sc->rl_flags & RL_FLAG_PCIE) != 0 &&
                      sc->rl_hwrev->rl_max_mtu == RL_MTU) {
                          /* RTL810x has no jumbo frame support. */
                          CSR_WRITE_2(sc, RL_MAXRXPKTLEN, RE_RX_DESC_BUFLEN);
                  } else
                          CSR_WRITE_2(sc, RL_MAXRXPKTLEN, 16383);
          }
  
          if (sc->rl_testmode)
                  return;
  
          CSR_WRITE_1(sc, sc->rl_cfg1, CSR_READ_1(sc, sc->rl_cfg1) |
              RL_CFG1_DRVLOAD);
  
          ifp->if_drv_flags |= IFF_DRV_RUNNING;
          ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
  
          sc->rl_flags &= ~RL_FLAG_LINK;
          mii_mediachg(mii);
  
          sc->rl_watchdog_timer = 0;
          callout_reset(&sc->rl_stat_callout, hz, re_tick, sc);
  
  #ifdef DEV_NETMAP
          netmap_enable_all_rings(ifp);
  #endif /* DEV_NETMAP */
  }
  
  /*
   * Set media options.
   */
  static int
  re_ifmedia_upd(struct ifnet *ifp)
  {
          struct rl_softc         *sc;
          struct mii_data         *mii;
          int                     error;
  
          sc = ifp->if_softc;
          mii = device_get_softc(sc->rl_miibus);
          RL_LOCK(sc);
          error = mii_mediachg(mii);
          RL_UNLOCK(sc);
  
          return (error);
  }
  
  /*
   * Report current media status.
   */
  static void
  re_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
  {
          struct rl_softc         *sc;
          struct mii_data         *mii;
  
          sc = ifp->if_softc;
          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
  re_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
  {
          struct rl_softc         *sc = ifp->if_softc;
          struct ifreq            *ifr = (struct ifreq *) data;
          struct mii_data         *mii;
          int                     error = 0;
  
          switch (command) {
          case SIOCSIFMTU:
                  if (ifr->ifr_mtu < ETHERMIN ||
                      ifr->ifr_mtu > sc->rl_hwrev->rl_max_mtu ||
                      ((sc->rl_flags & RL_FLAG_FASTETHER) != 0 &&
                      ifr->ifr_mtu > RL_MTU)) {
                          error = EINVAL;
                          break;
                  }
                  RL_LOCK(sc);
                  if (ifp->if_mtu != ifr->ifr_mtu) {
                          ifp->if_mtu = ifr->ifr_mtu;
                          if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0 &&
                              (ifp->if_drv_flags & IFF_DRV_RUNNING) != 0) {
                                  ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
                                  re_init_locked(sc);
                          }
                          if (ifp->if_mtu > RL_TSO_MTU &&
                              (ifp->if_capenable & IFCAP_TSO4) != 0) {
                                  ifp->if_capenable &= ~(IFCAP_TSO4 |
                                      IFCAP_VLAN_HWTSO);
                                  ifp->if_hwassist &= ~CSUM_TSO;
                          }
                          VLAN_CAPABILITIES(ifp);
                  }
                  RL_UNLOCK(sc);
                  break;
          case SIOCSIFFLAGS:
                  RL_LOCK(sc);
                  if ((ifp->if_flags & IFF_UP) != 0) {
                          if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0) {
                                  if (((ifp->if_flags ^ sc->rl_if_flags)
                                      & (IFF_PROMISC | IFF_ALLMULTI)) != 0)
                                          re_set_rxmode(sc);
                          } else
                                  re_init_locked(sc);
                  } else {
                          if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
                                  re_stop(sc);
                  }
                  sc->rl_if_flags = ifp->if_flags;
                  RL_UNLOCK(sc);
                  break;
          case SIOCADDMULTI:
          case SIOCDELMULTI:
                  RL_LOCK(sc);
                  if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
                          re_set_rxmode(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:
              {
                  int mask, reinit;
  
                  mask = ifr->ifr_reqcap ^ ifp->if_capenable;
                  reinit = 0;
  #ifdef DEVICE_POLLING
                  if (mask & IFCAP_POLLING) {
                          if (ifr->ifr_reqcap & IFCAP_POLLING) {
                                  error = ether_poll_register(re_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);
                          } else {
                                  error = ether_poll_deregister(ifp);
                                  /* Enable interrupts. */
                                  RL_LOCK(sc);
                                  CSR_WRITE_2(sc, RL_IMR, RL_INTRS_CPLUS);
                                  ifp->if_capenable &= ~IFCAP_POLLING;
                                  RL_UNLOCK(sc);
                          }
                  }
  #endif /* DEVICE_POLLING */
                  RL_LOCK(sc);
                  if ((mask & IFCAP_TXCSUM) != 0 &&
                      (ifp->if_capabilities & IFCAP_TXCSUM) != 0) {
                          ifp->if_capenable ^= IFCAP_TXCSUM;
                          if ((ifp->if_capenable & IFCAP_TXCSUM) != 0)
                                  ifp->if_hwassist |= RE_CSUM_FEATURES;
                          else
                                  ifp->if_hwassist &= ~RE_CSUM_FEATURES;
                          reinit = 1;
                  }
                  if ((mask & IFCAP_RXCSUM) != 0 &&
                      (ifp->if_capabilities & IFCAP_RXCSUM) != 0) {
                          ifp->if_capenable ^= IFCAP_RXCSUM;
                          reinit = 1;
                  }
                  if ((mask & IFCAP_TSO4) != 0 &&
                      (ifp->if_capabilities & IFCAP_TSO4) != 0) {
                          ifp->if_capenable ^= IFCAP_TSO4;
                          if ((IFCAP_TSO4 & ifp->if_capenable) != 0)
                                  ifp->if_hwassist |= CSUM_TSO;
                          else
                                  ifp->if_hwassist &= ~CSUM_TSO;
                          if (ifp->if_mtu > RL_TSO_MTU &&
                              (ifp->if_capenable & IFCAP_TSO4) != 0) {
                                  ifp->if_capenable &= ~IFCAP_TSO4;
                                  ifp->if_hwassist &= ~CSUM_TSO;
                          }
                  }
                  if ((mask & IFCAP_VLAN_HWTSO) != 0 &&
                      (ifp->if_capabilities & IFCAP_VLAN_HWTSO) != 0)
                          ifp->if_capenable ^= IFCAP_VLAN_HWTSO;
                  if ((mask & IFCAP_VLAN_HWTAGGING) != 0 &&
                      (ifp->if_capabilities & IFCAP_VLAN_HWTAGGING) != 0) {
                          ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING;
                          /* TSO over VLAN requires VLAN hardware tagging. */
                          if ((ifp->if_capenable & IFCAP_VLAN_HWTAGGING) == 0)
                                  ifp->if_capenable &= ~IFCAP_VLAN_HWTSO;
                          reinit = 1;
                  }
                  if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0 &&
                      (mask & (IFCAP_HWCSUM | IFCAP_TSO4 |
                      IFCAP_VLAN_HWTSO)) != 0)
                                  reinit = 1;
                  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;
                  }
                  if (reinit && ifp->if_drv_flags & IFF_DRV_RUNNING) {
                          ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
                          re_init_locked(sc);
                  }
                  RL_UNLOCK(sc);
                  VLAN_CAPABILITIES(ifp);
              }
                  break;
          default:
                  error = ether_ioctl(ifp, command, data);
                  break;
          }
  
          return (error);
  }
  
  static void
  re_watchdog(struct rl_softc *sc)
  {
          struct ifnet            *ifp;
  
          RL_LOCK_ASSERT(sc);
  
          if (sc->rl_watchdog_timer == 0 || --sc->rl_watchdog_timer != 0)
                  return;
  
          ifp = sc->rl_ifp;
          re_txeof(sc);
          if (sc->rl_ldata.rl_tx_free == sc->rl_ldata.rl_tx_desc_cnt) {
                  if_printf(ifp, "watchdog timeout (missed Tx interrupts) "
                      "-- recovering\n");
                  if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
                          re_start_locked(ifp);
                  return;
          }
  
          if_printf(ifp, "watchdog timeout\n");
          if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
  
          re_rxeof(sc, NULL);
          ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
          re_init_locked(sc);
          if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
                  re_start_locked(ifp);
  }
  
  /*
   * Stop the adapter and free any mbufs allocated to the
   * RX and TX lists.
   */
  static void
  re_stop(struct rl_softc *sc)
  {
          int                     i;
          struct ifnet            *ifp;
          struct rl_txdesc        *txd;
          struct rl_rxdesc        *rxd;
  
          RL_LOCK_ASSERT(sc);
  
          ifp = sc->rl_ifp;
  
          sc->rl_watchdog_timer = 0;
          callout_stop(&sc->rl_stat_callout);
          ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
  
  #ifdef DEV_NETMAP
          netmap_disable_all_rings(ifp);
  #endif /* DEV_NETMAP */
  
          /*
           * Disable accepting frames to put RX MAC into idle state.
           * Otherwise it's possible to get frames while stop command
           * execution is in progress and controller can DMA the frame
           * to already freed RX buffer during that period.
           */
          CSR_WRITE_4(sc, RL_RXCFG, CSR_READ_4(sc, RL_RXCFG) &
              ~(RL_RXCFG_RX_ALLPHYS | RL_RXCFG_RX_INDIV | RL_RXCFG_RX_MULTI |
              RL_RXCFG_RX_BROAD));
  
          if ((sc->rl_flags & RL_FLAG_8168G_PLUS) != 0) {
                  /* Enable RXDV gate. */
                  CSR_WRITE_4(sc, RL_MISC, CSR_READ_4(sc, RL_MISC) |
                      0x00080000);
          }
  
          if ((sc->rl_flags & RL_FLAG_WAIT_TXPOLL) != 0) {
                  for (i = RL_TIMEOUT; i > 0; i--) {
                          if ((CSR_READ_1(sc, sc->rl_txstart) &
                              RL_TXSTART_START) == 0)
                                  break;
                          DELAY(20);
                  }
                  if (i == 0)
                          device_printf(sc->rl_dev,
                              "stopping TX poll timed out!\n");
                  CSR_WRITE_1(sc, RL_COMMAND, 0x00);
          } else if ((sc->rl_flags & RL_FLAG_CMDSTOP) != 0) {
                  CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_STOPREQ | RL_CMD_TX_ENB |
                      RL_CMD_RX_ENB);
                  if ((sc->rl_flags & RL_FLAG_CMDSTOP_WAIT_TXQ) != 0) {
                          for (i = RL_TIMEOUT; i > 0; i--) {
                                  if ((CSR_READ_4(sc, RL_TXCFG) &
                                      RL_TXCFG_QUEUE_EMPTY) != 0)
                                          break;
                                  DELAY(100);
                          }
                          if (i == 0)
                                  device_printf(sc->rl_dev,
                                     "stopping TXQ timed out!\n");
                  }
          } else
                  CSR_WRITE_1(sc, RL_COMMAND, 0x00);
          DELAY(1000);
          CSR_WRITE_2(sc, RL_IMR, 0x0000);
          CSR_WRITE_2(sc, RL_ISR, 0xFFFF);
  
          if (sc->rl_head != NULL) {
                  m_freem(sc->rl_head);
                  sc->rl_head = sc->rl_tail = NULL;
          }
  
          /* Free the TX list buffers. */
          for (i = 0; i < sc->rl_ldata.rl_tx_desc_cnt; i++) {
                  txd = &sc->rl_ldata.rl_tx_desc[i];
                  if (txd->tx_m != NULL) {
                          bus_dmamap_sync(sc->rl_ldata.rl_tx_mtag,
                              txd->tx_dmamap, BUS_DMASYNC_POSTWRITE);
                          bus_dmamap_unload(sc->rl_ldata.rl_tx_mtag,
                              txd->tx_dmamap);
                          m_freem(txd->tx_m);
                          txd->tx_m = NULL;
                  }
          }
  
          /* Free the RX list buffers. */
          for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                  rxd = &sc->rl_ldata.rl_rx_desc[i];
                  if (rxd->rx_m != NULL) {
                          bus_dmamap_sync(sc->rl_ldata.rl_rx_mtag,
                              rxd->rx_dmamap, BUS_DMASYNC_POSTREAD);
                          bus_dmamap_unload(sc->rl_ldata.rl_rx_mtag,
                              rxd->rx_dmamap);
                          m_freem(rxd->rx_m);
                          rxd->rx_m = NULL;
                  }
          }
  
          if ((sc->rl_flags & RL_FLAG_JUMBOV2) != 0) {
                  for (i = 0; i < sc->rl_ldata.rl_rx_desc_cnt; i++) {
                          rxd = &sc->rl_ldata.rl_jrx_desc[i];
                          if (rxd->rx_m != NULL) {
                                  bus_dmamap_sync(sc->rl_ldata.rl_jrx_mtag,
                                      rxd->rx_dmamap, BUS_DMASYNC_POSTREAD);
                                  bus_dmamap_unload(sc->rl_ldata.rl_jrx_mtag,
                                      rxd->rx_dmamap);
                                  m_freem(rxd->rx_m);
                                  rxd->rx_m = NULL;
                          }
                  }
          }
  }
  
  /*
   * Device suspend routine.  Stop the interface and save some PCI
   * settings in case the BIOS doesn't restore them properly on
   * resume.
   */
  static int
  re_suspend(device_t dev)
  {
          struct rl_softc         *sc;
  
          sc = device_get_softc(dev);
  
          RL_LOCK(sc);
          re_stop(sc);
          re_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
  re_resume(device_t dev)
  {
          struct rl_softc         *sc;
          struct ifnet            *ifp;
  
          sc = device_get_softc(dev);
  
          RL_LOCK(sc);
  
          ifp = sc->rl_ifp;
          /* Take controller out of sleep mode. */
          if ((sc->rl_flags & RL_FLAG_MACSLEEP) != 0) {
                  if ((CSR_READ_1(sc, RL_MACDBG) & 0x80) == 0x80)
                          CSR_WRITE_1(sc, RL_GPIO,
                              CSR_READ_1(sc, RL_GPIO) | 0x01);
          }
  
          /*
           * Clear WOL matching such that normal Rx filtering
           * wouldn't interfere with WOL patterns.
           */
          re_clrwol(sc);
  
          /* reinitialize interface if necessary */
          if (ifp->if_flags & IFF_UP)
                  re_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
  re_shutdown(device_t dev)
  {
          struct rl_softc         *sc;
  
          sc = device_get_softc(dev);
  
          RL_LOCK(sc);
          re_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;
          re_setwol(sc);
          RL_UNLOCK(sc);
  
          return (0);
  }
  
  static void
  re_set_linkspeed(struct rl_softc *sc)
  {
          struct mii_softc *miisc;
          struct mii_data *mii;
          int aneg, i, phyno;
  
          RL_LOCK_ASSERT(sc);
  
          mii = device_get_softc(sc->rl_miibus);
          mii_pollstat(mii);
          aneg = 0;
          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:
                          return;
                  case IFM_1000_T:
                          aneg++;
                          break;
                  default:
                          break;
                  }
          }
          miisc = LIST_FIRST(&mii->mii_phys);
          phyno = miisc->mii_phy;
          LIST_FOREACH(miisc, &mii->mii_phys, mii_list)
                  PHY_RESET(miisc);
          re_miibus_writereg(sc->rl_dev, phyno, MII_100T2CR, 0);
          re_miibus_writereg(sc->rl_dev, phyno,
              MII_ANAR, ANAR_TX_FD | ANAR_TX | ANAR_10_FD | ANAR_10 | ANAR_CSMA);
          re_miibus_writereg(sc->rl_dev, phyno,
              MII_BMCR, BMCR_AUTOEN | BMCR_STARTNEG);
          DELAY(1000);
          if (aneg != 0) {
                  /*
                   * Poll link state until re(4) get a 10/100Mbps link.
                   */
                  for (i = 0; i < MII_ANEGTICKS_GIGE; i++) {
                          mii_pollstat(mii);
                          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:
                                          return;
                                  default:
                                          break;
                                  }
                          }
                          RL_UNLOCK(sc);
                          pause("relnk", hz);
                          RL_LOCK(sc);
                  }
                  if (i == MII_ANEGTICKS_GIGE)
                          device_printf(sc->rl_dev,
                              "establishing a link failed, WOL may not work!");
          }
          /*
           * No link, force MAC to have 100Mbps, full-duplex link.
           * MAC does not require reprogramming on resolved speed/duplex,
           * so this is just for completeness.
           */
          mii->mii_media_status = IFM_AVALID | IFM_ACTIVE;
          mii->mii_media_active = IFM_ETHER | IFM_100_TX | IFM_FDX;
  }
  
  static void
  re_setwol(struct rl_softc *sc)
  {
          struct ifnet            *ifp;
          int                     pmc;
          uint16_t                pmstat;
          uint8_t                 v;
  
          RL_LOCK_ASSERT(sc);
  
          if (pci_find_cap(sc->rl_dev, PCIY_PMG, &pmc) != 0)
                  return;
  
          ifp = sc->rl_ifp;
          /* Put controller into sleep mode. */
          if ((sc->rl_flags & RL_FLAG_MACSLEEP) != 0) {
                  if ((CSR_READ_1(sc, RL_MACDBG) & 0x80) == 0x80)
                          CSR_WRITE_1(sc, RL_GPIO,
                              CSR_READ_1(sc, RL_GPIO) & ~0x01);
          }
          if ((ifp->if_capenable & IFCAP_WOL) != 0) {
                  if ((sc->rl_flags & RL_FLAG_8168G_PLUS) != 0) {
                          /* Disable RXDV gate. */
                          CSR_WRITE_4(sc, RL_MISC, CSR_READ_4(sc, RL_MISC) &
                              ~0x00080000);
                  }
                  re_set_rxmode(sc);
                  if ((sc->rl_flags & RL_FLAG_WOL_MANLINK) != 0)
                          re_set_linkspeed(sc);
                  if ((sc->rl_flags & RL_FLAG_WOLRXENB) != 0)
                          CSR_WRITE_1(sc, RL_COMMAND, RL_CMD_RX_ENB);
          }
          /* 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 |
              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);
  
          if ((ifp->if_capenable & IFCAP_WOL) == 0 &&
              (sc->rl_flags & RL_FLAG_PHYWAKE_PM) != 0)
                  CSR_WRITE_1(sc, RL_PMCH, CSR_READ_1(sc, RL_PMCH) & ~0x80);
          /*
           * It seems that hardware resets its link speed to 100Mbps in
           * power down mode so switching to 100Mbps in driver is not
           * needed.
           */
  
          /* 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
  re_clrwol(struct rl_softc *sc)
  {
          int                     pmc;
          uint8_t                 v;
  
          RL_LOCK_ASSERT(sc);
  
          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);
  
          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);
  }
  
  static void
  re_add_sysctls(struct rl_softc *sc)
  {
          struct sysctl_ctx_list  *ctx;
          struct sysctl_oid_list  *children;
          int                     error;
  
          ctx = device_get_sysctl_ctx(sc->rl_dev);
          children = SYSCTL_CHILDREN(device_get_sysctl_tree(sc->rl_dev));
  
          SYSCTL_ADD_PROC(ctx, children, OID_AUTO, "stats",
              CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc, 0,
              re_sysctl_stats, "I", "Statistics Information");
          if ((sc->rl_flags & (RL_FLAG_MSI | RL_FLAG_MSIX)) == 0)
                  return;
  
          SYSCTL_ADD_PROC(ctx, children, OID_AUTO, "int_rx_mod",
              CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
              &sc->rl_int_rx_mod, 0, sysctl_hw_re_int_mod, "I",
              "re RX interrupt moderation");
          /* Pull in device tunables. */
          sc->rl_int_rx_mod = RL_TIMER_DEFAULT;
          error = resource_int_value(device_get_name(sc->rl_dev),
              device_get_unit(sc->rl_dev), "int_rx_mod", &sc->rl_int_rx_mod);
          if (error == 0) {
                  if (sc->rl_int_rx_mod < RL_TIMER_MIN ||
                      sc->rl_int_rx_mod > RL_TIMER_MAX) {
                          device_printf(sc->rl_dev, "int_rx_mod value out of "
                              "range; using default: %d\n",
                              RL_TIMER_DEFAULT);
                          sc->rl_int_rx_mod = RL_TIMER_DEFAULT;
                  }
          }
  }
  
  static int
  re_sysctl_stats(SYSCTL_HANDLER_ARGS)
  {
          struct rl_softc         *sc;
          struct rl_stats         *stats;
          int                     error, i, result;
  
          result = -1;
          error = sysctl_handle_int(oidp, &result, 0, req);
          if (error || req->newptr == NULL)
                  return (error);
  
          if (result == 1) {
                  sc = (struct rl_softc *)arg1;
                  RL_LOCK(sc);
                  if ((sc->rl_ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
                          RL_UNLOCK(sc);
                          goto done;
                  }
                  bus_dmamap_sync(sc->rl_ldata.rl_stag,
                      sc->rl_ldata.rl_smap, BUS_DMASYNC_PREREAD);
                  CSR_WRITE_4(sc, RL_DUMPSTATS_HI,
                      RL_ADDR_HI(sc->rl_ldata.rl_stats_addr));
                  CSR_WRITE_4(sc, RL_DUMPSTATS_LO,
                      RL_ADDR_LO(sc->rl_ldata.rl_stats_addr));
                  CSR_WRITE_4(sc, RL_DUMPSTATS_LO,
                      RL_ADDR_LO(sc->rl_ldata.rl_stats_addr |
                      RL_DUMPSTATS_START));
                  for (i = RL_TIMEOUT; i > 0; i--) {
                          if ((CSR_READ_4(sc, RL_DUMPSTATS_LO) &
                              RL_DUMPSTATS_START) == 0)
                                  break;
                          DELAY(1000);
                  }
                  bus_dmamap_sync(sc->rl_ldata.rl_stag,
                      sc->rl_ldata.rl_smap, BUS_DMASYNC_POSTREAD);
                  RL_UNLOCK(sc);
                  if (i == 0) {
                          device_printf(sc->rl_dev,
                              "DUMP statistics request timed out\n");
                          return (ETIMEDOUT);
                  }
  done:
                  stats = sc->rl_ldata.rl_stats;
                  printf("%s statistics:\n", device_get_nameunit(sc->rl_dev));
                  printf("Tx frames : %ju\n",
                      (uintmax_t)le64toh(stats->rl_tx_pkts));
                  printf("Rx frames : %ju\n",
                      (uintmax_t)le64toh(stats->rl_rx_pkts));
                  printf("Tx errors : %ju\n",
                      (uintmax_t)le64toh(stats->rl_tx_errs));
                  printf("Rx errors : %u\n",
                      le32toh(stats->rl_rx_errs));
                  printf("Rx missed frames : %u\n",
                      (uint32_t)le16toh(stats->rl_missed_pkts));
                  printf("Rx frame alignment errs : %u\n",
                      (uint32_t)le16toh(stats->rl_rx_framealign_errs));
                  printf("Tx single collisions : %u\n",
                      le32toh(stats->rl_tx_onecoll));
                  printf("Tx multiple collisions : %u\n",
                      le32toh(stats->rl_tx_multicolls));
                  printf("Rx unicast frames : %ju\n",
                      (uintmax_t)le64toh(stats->rl_rx_ucasts));
                  printf("Rx broadcast frames : %ju\n",
                      (uintmax_t)le64toh(stats->rl_rx_bcasts));
                  printf("Rx multicast frames : %u\n",
                      le32toh(stats->rl_rx_mcasts));
                  printf("Tx aborts : %u\n",
                      (uint32_t)le16toh(stats->rl_tx_aborts));
                  printf("Tx underruns : %u\n",
                      (uint32_t)le16toh(stats->rl_rx_underruns));
          }
  
          return (error);
  }
  
  static int
  sysctl_int_range(SYSCTL_HANDLER_ARGS, int low, int high)
  {
          int error, value;
  
          if (arg1 == NULL)
                  return (EINVAL);
          value = *(int *)arg1;
          error = sysctl_handle_int(oidp, &value, 0, req);
          if (error || req->newptr == NULL)
                  return (error);
          if (value < low || value > high)
                  return (EINVAL);
          *(int *)arg1 = value;
  
          return (0);
  }
  
  static int
  sysctl_hw_re_int_mod(SYSCTL_HANDLER_ARGS)
  {
  
          return (sysctl_int_range(oidp, arg1, arg2, req, RL_TIMER_MIN,
              RL_TIMER_MAX));
  }
  
  #ifdef DEBUGNET
  static void
  re_debugnet_init(struct ifnet *ifp, int *nrxr, int *ncl, int *clsize)
  {
          struct rl_softc *sc;
  
          sc = if_getsoftc(ifp);
          RL_LOCK(sc);
          *nrxr = sc->rl_ldata.rl_rx_desc_cnt;
          *ncl = DEBUGNET_MAX_IN_FLIGHT;
          *clsize = (ifp->if_mtu > RL_MTU &&
              (sc->rl_flags & RL_FLAG_JUMBOV2) != 0) ? MJUM9BYTES : MCLBYTES;
          RL_UNLOCK(sc);
  }
  
  static void
  re_debugnet_event(struct ifnet *ifp __unused, enum debugnet_ev event __unused)
  {
  }
  
  static int
  re_debugnet_transmit(struct ifnet *ifp, struct mbuf *m)
  {
          struct rl_softc *sc;
          int error;
  
          sc = if_getsoftc(ifp);
          if ((if_getdrvflags(ifp) & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
              IFF_DRV_RUNNING || (sc->rl_flags & RL_FLAG_LINK) == 0)
                  return (EBUSY);
  
          error = re_encap(sc, &m);
          if (error == 0)
                  re_start_tx(sc);
          return (error);
  }
  
  static int
  re_debugnet_poll(struct ifnet *ifp, int count)
  {
          struct rl_softc *sc;
          int error;
  
          sc = if_getsoftc(ifp);
          if ((if_getdrvflags(ifp) & IFF_DRV_RUNNING) == 0 ||
              (sc->rl_flags & RL_FLAG_LINK) == 0)
                  return (EBUSY);
  
          re_txeof(sc);
          error = re_rxeof(sc, NULL);
          if (error != 0 && error != EAGAIN)
                  return (error);
          return (0);
  }
  #endif /* DEBUGNET */