root/sys/dev/pci/igc/if_igc.c
/*      $NetBSD: if_igc.c,v 1.25 2026/06/10 21:02:49 wiz Exp $  */
/*      $OpenBSD: if_igc.c,v 1.13 2023/04/28 10:18:57 bluhm Exp $       */
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2016 Nicole Graziano <nicole@nextbsd.org>
 * All rights reserved.
 * Copyright (c) 2021 Rubicon Communications, LLC (Netgate)
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_igc.c,v 1.25 2026/06/10 21:02:49 wiz Exp $");

#ifdef _KERNEL_OPT
#include "opt_if_igc.h"
#if 0 /* notyet */
#include "vlan.h"
#endif
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/cpu.h>
#include <sys/device.h>
#include <sys/endian.h>
#include <sys/intr.h>
#include <sys/interrupt.h>
#include <sys/kernel.h>
#include <sys/kmem.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/workqueue.h>
#include <sys/xcall.h>
#include <sys/module.h>

#include <net/bpf.h>
#include <net/if.h>
#include <net/if_ether.h>
#include <net/if_media.h>
#include <net/if_vlanvar.h>
#include <net/rss_config.h>

#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/tcp.h>

#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcidevs.h>

#include <dev/pci/igc/if_igc.h>
#include <dev/pci/igc/igc_evcnt.h>
#include <dev/pci/igc/igc_hw.h>
#include <dev/mii/miivar.h>

#define IGC_WORKQUEUE_PRI       PRI_SOFTNET

#ifndef IGC_RX_INTR_PROCESS_LIMIT_DEFAULT
#define IGC_RX_INTR_PROCESS_LIMIT_DEFAULT       0
#endif
#ifndef IGC_TX_INTR_PROCESS_LIMIT_DEFAULT
#define IGC_TX_INTR_PROCESS_LIMIT_DEFAULT       0
#endif

#ifndef IGC_RX_PROCESS_LIMIT_DEFAULT
#define IGC_RX_PROCESS_LIMIT_DEFAULT            256
#endif
#ifndef IGC_TX_PROCESS_LIMIT_DEFAULT
#define IGC_TX_PROCESS_LIMIT_DEFAULT            256
#endif

#define htolem32(p, x)  (*((uint32_t *)(p)) = htole32(x))
#define htolem64(p, x)  (*((uint64_t *)(p)) = htole64(x))

static const struct igc_product {
        pci_vendor_id_t         igcp_vendor;
        pci_product_id_t        igcp_product;
        const char              *igcp_name;
} igc_products[] = {
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_IT,
            "Intel(R) Ethernet Controller I225-IT(2)" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I226_LM,
            "Intel(R) Ethernet Controller I226-LM" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I226_V,
            "Intel(R) Ethernet Controller I226-V" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I226_IT,
            "Intel(R) Ethernet Controller I226-IT" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I221_V,
            "Intel(R) Ethernet Controller I221-V" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I226_BLANK_NVM,
            "Intel(R) Ethernet Controller I226(blankNVM)" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_LM,
            "Intel(R) Ethernet Controller I225-LM" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_V,
            "Intel(R) Ethernet Controller I225-V" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I220_V,
            "Intel(R) Ethernet Controller I220-V" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_I,
            "Intel(R) Ethernet Controller I225-I" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_BLANK_NVM,
            "Intel(R) Ethernet Controller I225(blankNVM)" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_K,
            "Intel(R) Ethernet Controller I225-K" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_K2,
            "Intel(R) Ethernet Controller I225-K(2)" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I226_K,
            "Intel(R) Ethernet Controller I226-K" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I225_LMVP,
            "Intel(R) Ethernet Controller I225-LMvP(2)" },
        { PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_I226_LMVP,
            "Intel(R) Ethernet Controller I226-LMvP" },
        { 0, 0, NULL },
};

#define IGC_DF_CFG      0x1
#define IGC_DF_TX       0x2
#define IGC_DF_RX       0x4
#define IGC_DF_MISC     0x8

#ifdef IGC_DEBUG_FLAGS
int igc_debug_flags = IGC_DEBUG_FLAGS;
#else
int igc_debug_flags = 0;
#endif

#define DPRINTF(flag, fmt, args...)             do {                    \
        if (igc_debug_flags & (IGC_DF_ ## flag))                        \
                printf("%s: %d: " fmt, __func__, __LINE__, ##args);     \
    } while (0)

/*********************************************************************
 *  Function Prototypes
 *********************************************************************/
static int      igc_match(device_t, cfdata_t, void *);
static void     igc_attach(device_t, device_t, void *);
static int      igc_detach(device_t, int);

static void     igc_identify_hardware(struct igc_softc *);
static int      igc_adjust_nqueues(struct igc_softc *);
static int      igc_allocate_pci_resources(struct igc_softc *);
static int      igc_allocate_interrupts(struct igc_softc *);
static int      igc_allocate_queues(struct igc_softc *);
static void     igc_free_pci_resources(struct igc_softc *);
static void     igc_free_interrupts(struct igc_softc *);
static void     igc_free_queues(struct igc_softc *);
static void     igc_reset(struct igc_softc *);
static void     igc_init_dmac(struct igc_softc *, uint32_t);
static int      igc_setup_interrupts(struct igc_softc *);
static void     igc_attach_counters(struct igc_softc *sc);
static void     igc_detach_counters(struct igc_softc *sc);
static void     igc_update_counters(struct igc_softc *sc);
static void     igc_clear_counters(struct igc_softc *sc);
static int      igc_setup_msix(struct igc_softc *);
static int      igc_setup_msi(struct igc_softc *);
static int      igc_setup_intx(struct igc_softc *);
static int      igc_dma_malloc(struct igc_softc *, bus_size_t,
                    struct igc_dma_alloc *);
static void     igc_dma_free(struct igc_softc *, struct igc_dma_alloc *);
static void     igc_setup_interface(struct igc_softc *);

static int      igc_init(struct ifnet *);
static int      igc_init_locked(struct igc_softc *);
static void     igc_start(struct ifnet *);
static int      igc_transmit(struct ifnet *, struct mbuf *);
static void     igc_tx_common_locked(struct ifnet *, struct tx_ring *, int);
static bool     igc_txeof(struct tx_ring *, u_int);
static void     igc_intr_barrier(struct igc_softc *);
static void     igc_stop(struct ifnet *, int);
static void     igc_stop_locked(struct igc_softc *);
static int      igc_ioctl(struct ifnet *, u_long, void *);
#ifdef IF_RXR
static int      igc_rxrinfo(struct igc_softc *, struct if_rxrinfo *);
#endif
static void     igc_rxfill(struct rx_ring *);
static bool     igc_rxrefill(struct rx_ring *);
static void     igc_rxrefill_callout(void *);
static bool     igc_rxeof(struct rx_ring *, u_int);
static int      igc_rx_checksum(struct igc_queue *, uint64_t, uint32_t,
                    uint32_t);
static void     igc_watchdog(struct ifnet *);
static void     igc_tick(void *);
static void     igc_media_status(struct ifnet *, struct ifmediareq *);
static int      igc_media_change(struct ifnet *);
static int      igc_ifflags_cb(struct ethercom *);
static void     igc_set_filter(struct igc_softc *);
static void     igc_update_link_status(struct igc_softc *);
static int      igc_get_buf(struct rx_ring *, int, bool);
static bool     igc_tx_ctx_setup(struct tx_ring *, struct mbuf *, int,
                    uint32_t *, uint32_t *);

static void     igc_configure_queues(struct igc_softc *);
static void     igc_set_queues(struct igc_softc *, uint32_t, uint32_t, int);
static void     igc_enable_queue(struct igc_softc *, uint32_t);
static void     igc_enable_intr(struct igc_softc *);
static void     igc_disable_intr(struct igc_softc *);
static int      igc_intr_link(void *);
static int      igc_intr_queue(void *);
static int      igc_intr(void *);
static void     igc_handle_queue(void *);
static void     igc_handle_queue_work(struct work *, void *);
static void     igc_sched_handle_queue(struct igc_softc *, struct igc_queue *);
static void     igc_barrier_handle_queue(struct igc_softc *);

static int      igc_allocate_transmit_buffers(struct tx_ring *);
static int      igc_setup_transmit_structures(struct igc_softc *);
static int      igc_setup_transmit_ring(struct tx_ring *);
static void     igc_initialize_transmit_unit(struct igc_softc *);
static void     igc_free_transmit_structures(struct igc_softc *);
static void     igc_free_transmit_buffers(struct tx_ring *);
static void     igc_withdraw_transmit_packets(struct tx_ring *, bool);
static int      igc_allocate_receive_buffers(struct rx_ring *);
static int      igc_setup_receive_structures(struct igc_softc *);
static int      igc_setup_receive_ring(struct rx_ring *);
static void     igc_initialize_receive_unit(struct igc_softc *);
static void     igc_free_receive_structures(struct igc_softc *);
static void     igc_free_receive_buffers(struct rx_ring *);
static void     igc_clear_receive_status(struct rx_ring *);
static void     igc_initialize_rss_mapping(struct igc_softc *);

static void     igc_get_hw_control(struct igc_softc *);
static void     igc_release_hw_control(struct igc_softc *);
static int      igc_is_valid_ether_addr(uint8_t *);
static void     igc_print_devinfo(struct igc_softc *);

CFATTACH_DECL3_NEW(igc, sizeof(struct igc_softc),
    igc_match, igc_attach, igc_detach, NULL, NULL, NULL, 0);

static inline int
igc_txdesc_incr(struct igc_softc *sc, int id)
{

        if (++id == sc->num_tx_desc)
                id = 0;
        return id;
}

static inline int __unused
igc_txdesc_decr(struct igc_softc *sc, int id)
{

        if (--id < 0)
                id = sc->num_tx_desc - 1;
        return id;
}

static inline void
igc_txdesc_sync(struct tx_ring *txr, int id, int ops)
{

        bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map,
            id * sizeof(union igc_adv_tx_desc), sizeof(union igc_adv_tx_desc),
            ops);
}

static inline int
igc_rxdesc_incr(struct igc_softc *sc, int id)
{

        if (++id == sc->num_rx_desc)
                id = 0;
        return id;
}

static inline int
igc_rxdesc_decr(struct igc_softc *sc, int id)
{

        if (--id < 0)
                id = sc->num_rx_desc - 1;
        return id;
}

static inline void
igc_rxdesc_sync(struct rx_ring *rxr, int id, int ops)
{

        bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map,
            id * sizeof(union igc_adv_rx_desc), sizeof(union igc_adv_rx_desc),
            ops);
}

static const struct igc_product *
igc_lookup(const struct pci_attach_args *pa)
{
        const struct igc_product *igcp;

        for (igcp = igc_products; igcp->igcp_name != NULL; igcp++) {
                if (PCI_VENDOR(pa->pa_id) == igcp->igcp_vendor &&
                    PCI_PRODUCT(pa->pa_id) == igcp->igcp_product)
                        return igcp;
        }
        return NULL;
}

/*********************************************************************
 *  Device identification routine
 *
 *  igc_match determines if the driver should be loaded on
 *  adapter based on PCI vendor/device id of the adapter.
 *
 *  return 0 on success, positive on failure
 *********************************************************************/
static int
igc_match(device_t parent, cfdata_t match, void *aux)
{
        struct pci_attach_args *pa = aux;

        if (igc_lookup(pa) != NULL)
                return 1;

        return 0;
}

/*********************************************************************
 *  Device initialization routine
 *
 *  The attach entry point is called when the driver is being loaded.
 *  This routine identifies the type of hardware, allocates all resources
 *  and initializes the hardware.
 *
 *  return 0 on success, positive on failure
 *********************************************************************/
static void
igc_attach(device_t parent, device_t self, void *aux)
{
        struct pci_attach_args *pa = aux;
        struct igc_softc *sc = device_private(self);
        struct igc_hw *hw = &sc->hw;

        const struct igc_product *igcp = igc_lookup(pa);
        KASSERT(igcp != NULL);

        sc->sc_dev = self;
        callout_init(&sc->sc_tick_ch, CALLOUT_MPSAFE);
        callout_setfunc(&sc->sc_tick_ch, igc_tick, sc);
        sc->sc_core_stopping = false;

        sc->osdep.os_sc = sc;
        sc->osdep.os_pa = *pa;
#ifndef __aarch64__
        /*
         * XXX PR port-arm/57643
         * 64-bit DMA does not work at least for LX2K with 32/64GB memory.
         * smmu(4) support may be required.
         */
        if (pci_dma64_available(pa)) {
                aprint_verbose(", 64-bit DMA");
                sc->osdep.os_dmat = pa->pa_dmat64;
        } else
#endif
        {
                aprint_verbose(", 32-bit DMA");
                sc->osdep.os_dmat = pa->pa_dmat;
        }

        pci_aprint_devinfo_fancy(pa, "Ethernet controller", igcp->igcp_name, 1);

        /* Determine hardware and mac info */
        igc_identify_hardware(sc);

        sc->num_tx_desc = IGC_DEFAULT_TXD;
        sc->num_rx_desc = IGC_DEFAULT_RXD;

         /* Setup PCI resources */
        if (igc_allocate_pci_resources(sc)) {
                aprint_error_dev(sc->sc_dev,
                    "unable to allocate PCI resources\n");
                goto err;
        }

        if (igc_allocate_interrupts(sc)) {
                aprint_error_dev(sc->sc_dev, "unable to allocate interrupts\n");
                goto err_pci;
        }

        /* Allocate TX/RX queues */
        if (igc_allocate_queues(sc)) {
                aprint_error_dev(sc->sc_dev, "unable to allocate queues\n");
                goto err_alloc_intr;
        }

        /* Do shared code initialization */
        if (igc_setup_init_funcs(hw, true)) {
                aprint_error_dev(sc->sc_dev, "unable to initialize\n");
                goto err_alloc_intr;
        }

        hw->mac.autoneg = DO_AUTO_NEG;
        hw->phy.autoneg_wait_to_complete = false;
        hw->phy.autoneg_advertised = AUTONEG_ADV_DEFAULT;

        /* Copper options. */
        if (hw->phy.media_type == igc_media_type_copper)
                hw->phy.mdix = AUTO_ALL_MODES;

        /* Set the max frame size. */
        sc->hw.mac.max_frame_size = 9234;

        /* Allocate multicast array memory. */
        sc->mta = kmem_alloc(IGC_MTA_LEN, KM_SLEEP);

        /* Check SOL/IDER usage. */
        if (igc_check_reset_block(hw)) {
                aprint_error_dev(sc->sc_dev,
                    "PHY reset is blocked due to SOL/IDER session\n");
        }

        /* Disable Energy Efficient Ethernet. */
        sc->hw.dev_spec._i225.eee_disable = true;

        igc_reset_hw(hw);

        /* Make sure we have a good EEPROM before we read from it. */
        if (igc_validate_nvm_checksum(hw) < 0) {
                /*
                 * Some PCI-E parts fail the first check due to
                 * the link being in sleep state, call it again,
                 * if it fails a second time its a real issue.
                 */
                if (igc_validate_nvm_checksum(hw) < 0) {
                        aprint_error_dev(sc->sc_dev,
                            "EEPROM checksum invalid\n");
                        goto err_late;
                }
        }

        /* Copy the permanent MAC address out of the EEPROM. */
        if (igc_read_mac_addr(hw) < 0) {
                aprint_error_dev(sc->sc_dev,
                    "unable to read MAC address from EEPROM\n");
                goto err_late;
        }

        if (!igc_is_valid_ether_addr(hw->mac.addr)) {
                aprint_error_dev(sc->sc_dev, "invalid MAC address\n");
                goto err_late;
        }

        if (igc_setup_interrupts(sc))
                goto err_late;

        /* Attach counters. */
        igc_attach_counters(sc);

        /* Setup OS specific network interface. */
        igc_setup_interface(sc);

        igc_print_devinfo(sc);

        igc_reset(sc);
        hw->mac.get_link_status = true;
        igc_update_link_status(sc);

        /* The driver can now take control from firmware. */
        igc_get_hw_control(sc);

        aprint_normal_dev(sc->sc_dev, "Ethernet address %s\n",
            ether_sprintf(sc->hw.mac.addr));

        if (pmf_device_register(self, NULL, NULL))
                pmf_class_network_register(self, &sc->sc_ec.ec_if);
        else
                aprint_error_dev(self, "couldn't establish power handler\n");

        return;

 err_late:
        igc_release_hw_control(sc);
        kmem_free(sc->mta, IGC_MTA_LEN);
 err_alloc_intr:
        igc_free_interrupts(sc);
 err_pci:
        igc_free_pci_resources(sc);
 err:   return;
}

/*********************************************************************
 *  Device removal routine
 *
 *  The detach entry point is called when the driver is being removed.
 *  This routine stops the adapter and deallocates all the resources
 *  that were allocated for driver operation.
 *
 *  return 0 on success, positive on failure
 *********************************************************************/
static int
igc_detach(device_t self, int flags)
{
        struct igc_softc *sc = device_private(self);
        struct ifnet *ifp = &sc->sc_ec.ec_if;

        mutex_enter(&sc->sc_core_lock);
        igc_stop_locked(sc);
        mutex_exit(&sc->sc_core_lock);

        igc_detach_counters(sc);

        igc_free_queues(sc);

        igc_phy_hw_reset(&sc->hw);
        igc_release_hw_control(sc);

        ether_ifdetach(ifp);
        if_detach(ifp);
        ifmedia_fini(&sc->media);

        igc_free_interrupts(sc);
        igc_free_pci_resources(sc);
        kmem_free(sc->mta, IGC_MTA_LEN);

        mutex_destroy(&sc->sc_core_lock);

        return 0;
}

static void
igc_identify_hardware(struct igc_softc *sc)
{
        struct igc_osdep *os = &sc->osdep;
        struct pci_attach_args *pa = &os->os_pa;

        /* Save off the information about this board. */
        sc->hw.device_id = PCI_PRODUCT(pa->pa_id);

        /* Do shared code init and setup. */
        if (igc_set_mac_type(&sc->hw)) {
                aprint_error_dev(sc->sc_dev, "unable to identify hardware\n");
                return;
        }
}

static int
igc_allocate_pci_resources(struct igc_softc *sc)
{
        struct igc_osdep *os = &sc->osdep;
        struct pci_attach_args *pa = &os->os_pa;

        /*
         * Enable bus mastering and memory-mapped I/O for sure.
         */
        pcireg_t csr =
            pci_conf_read(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG);
        csr |= PCI_COMMAND_MASTER_ENABLE | PCI_COMMAND_MEM_ENABLE;
        pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG, csr);

        const pcireg_t memtype =
            pci_mapreg_type(pa->pa_pc, pa->pa_tag, IGC_PCIREG);
        if (pci_mapreg_map(pa, IGC_PCIREG, memtype, 0, &os->os_memt,
            &os->os_memh, &os->os_membase, &os->os_memsize)) {
                aprint_error_dev(sc->sc_dev, "unable to map registers\n");
                return ENXIO;
        }

        sc->hw.hw_addr = os->os_membase;
        sc->hw.back = os;

        return 0;
}

static int __unused
igc_adjust_nqueues(struct igc_softc *sc)
{
        struct pci_attach_args *pa = &sc->osdep.os_pa;
        int nqueues = MIN(IGC_MAX_NQUEUES, ncpu);

        const int nmsix = pci_msix_count(pa->pa_pc, pa->pa_tag);
        if (nmsix <= 1)
                nqueues = 1;
        else if (nmsix < nqueues + 1)
                nqueues = nmsix - 1;

        return nqueues;
}

static int
igc_allocate_interrupts(struct igc_softc *sc)
{
        struct pci_attach_args *pa = &sc->osdep.os_pa;
        int error;

#ifndef IGC_DISABLE_MSIX
        const int nqueues = igc_adjust_nqueues(sc);
        if (nqueues > 1) {
                sc->sc_nintrs = nqueues + 1;
                error = pci_msix_alloc_exact(pa, &sc->sc_intrs, sc->sc_nintrs);
                if (!error) {
                        sc->sc_nqueues = nqueues;
                        sc->sc_intr_type = PCI_INTR_TYPE_MSIX;
                        return 0;
                }
        }
#endif

        /* fallback to MSI */
        sc->sc_nintrs = sc->sc_nqueues = 1;

#ifndef IGC_DISABLE_MSI
        error = pci_msi_alloc_exact(pa, &sc->sc_intrs, sc->sc_nintrs);
        if (!error) {
                sc->sc_intr_type = PCI_INTR_TYPE_MSI;
                return 0;
        }
#endif

        /* fallback to INTx */

        error = pci_intx_alloc(pa, &sc->sc_intrs);
        if (!error) {
                sc->sc_intr_type = PCI_INTR_TYPE_INTX;
                return 0;
        }

        return error;
}

static int
igc_allocate_queues(struct igc_softc *sc)
{
        device_t dev = sc->sc_dev;
        int rxconf = 0, txconf = 0;

        /* Allocate the top level queue structs. */
        sc->queues =
            kmem_zalloc(sc->sc_nqueues * sizeof(struct igc_queue), KM_SLEEP);

        /* Allocate the TX ring. */
        sc->tx_rings =
            kmem_zalloc(sc->sc_nqueues * sizeof(struct tx_ring), KM_SLEEP);

        /* Allocate the RX ring. */
        sc->rx_rings =
            kmem_zalloc(sc->sc_nqueues * sizeof(struct rx_ring), KM_SLEEP);

        /* Set up the TX queues. */
        for (int iq = 0; iq < sc->sc_nqueues; iq++, txconf++) {
                struct tx_ring *txr = &sc->tx_rings[iq];
                const int tsize = roundup2(
                    sc->num_tx_desc * sizeof(union igc_adv_tx_desc),
                    IGC_DBA_ALIGN);

                txr->sc = sc;
                txr->txr_igcq = &sc->queues[iq];
                txr->me = iq;
                if (igc_dma_malloc(sc, tsize, &txr->txdma)) {
                        aprint_error_dev(dev,
                            "unable to allocate TX descriptor\n");
                        goto fail;
                }
                txr->tx_base = (union igc_adv_tx_desc *)txr->txdma.dma_vaddr;
                memset(txr->tx_base, 0, tsize);
        }

        /* Prepare transmit descriptors and buffers. */
        if (igc_setup_transmit_structures(sc)) {
                aprint_error_dev(dev, "unable to setup transmit structures\n");
                goto fail;
        }

        /* Set up the RX queues. */
        for (int iq = 0; iq < sc->sc_nqueues; iq++, rxconf++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];
                const int rsize = roundup2(
                    sc->num_rx_desc * sizeof(union igc_adv_rx_desc),
                    IGC_DBA_ALIGN);

                rxr->sc = sc;
                rxr->rxr_igcq = &sc->queues[iq];
                rxr->me = iq;
#ifdef OPENBSD
                timeout_set(&rxr->rx_refill, igc_rxrefill, rxr);
#endif
                callout_init(&rxr->rx_refill, CALLOUT_MPSAFE);
                callout_setfunc(&rxr->rx_refill, igc_rxrefill_callout, rxr);

                if (igc_dma_malloc(sc, rsize, &rxr->rxdma)) {
                        aprint_error_dev(dev,
                            "unable to allocate RX descriptor\n");
                        goto fail;
                }
                rxr->rx_base = (union igc_adv_rx_desc *)rxr->rxdma.dma_vaddr;
                memset(rxr->rx_base, 0, rsize);
        }

        sc->rx_mbuf_sz = MCLBYTES;
        /* Prepare receive descriptors and buffers. */
        if (igc_setup_receive_structures(sc)) {
                aprint_error_dev(sc->sc_dev,
                    "unable to setup receive structures\n");
                goto fail;
        }

        /* Set up the queue holding structs. */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                q->sc = sc;
                q->txr = &sc->tx_rings[iq];
                q->rxr = &sc->rx_rings[iq];
        }

        return 0;

 fail:
        for (struct rx_ring *rxr = sc->rx_rings; rxconf > 0; rxr++, rxconf--)
                igc_dma_free(sc, &rxr->rxdma);
        for (struct tx_ring *txr = sc->tx_rings; txconf > 0; txr++, txconf--)
                igc_dma_free(sc, &txr->txdma);

        kmem_free(sc->rx_rings, sc->sc_nqueues * sizeof(struct rx_ring));
        sc->rx_rings = NULL;
        kmem_free(sc->tx_rings, sc->sc_nqueues * sizeof(struct tx_ring));
        sc->tx_rings = NULL;
        kmem_free(sc->queues, sc->sc_nqueues * sizeof(struct igc_queue));
        sc->queues = NULL;

        return ENOMEM;
}

static void
igc_free_pci_resources(struct igc_softc *sc)
{
        struct igc_osdep *os = &sc->osdep;

        if (os->os_membase != 0)
                bus_space_unmap(os->os_memt, os->os_memh, os->os_memsize);
        os->os_membase = 0;
}

static void
igc_free_interrupts(struct igc_softc *sc)
{
        struct pci_attach_args *pa = &sc->osdep.os_pa;
        pci_chipset_tag_t pc = pa->pa_pc;

        for (int i = 0; i < sc->sc_nintrs; i++) {
                if (sc->sc_ihs[i] != NULL) {
                        pci_intr_disestablish(pc, sc->sc_ihs[i]);
                        sc->sc_ihs[i] = NULL;
                }
        }
        pci_intr_release(pc, sc->sc_intrs, sc->sc_nintrs);
}

static void
igc_free_queues(struct igc_softc *sc)
{

        igc_free_receive_structures(sc);
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];

                igc_dma_free(sc, &rxr->rxdma);
        }

        igc_free_transmit_structures(sc);
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct tx_ring *txr = &sc->tx_rings[iq];

                igc_dma_free(sc, &txr->txdma);
        }

        kmem_free(sc->rx_rings, sc->sc_nqueues * sizeof(struct rx_ring));
        kmem_free(sc->tx_rings, sc->sc_nqueues * sizeof(struct tx_ring));
        kmem_free(sc->queues, sc->sc_nqueues * sizeof(struct igc_queue));
}

/*********************************************************************
 *
 *  Initialize the hardware to a configuration as specified by the
 *  adapter structure.
 *
 **********************************************************************/
static void
igc_reset(struct igc_softc *sc)
{
        struct igc_hw *hw = &sc->hw;

        /* Let the firmware know the OS is in control */
        igc_get_hw_control(sc);

        /*
         * Packet Buffer Allocation (PBA)
         * Writing PBA sets the receive portion of the buffer
         * the remainder is used for the transmit buffer.
         */
        const uint32_t pba = IGC_PBA_34K;

        /*
         * These parameters control the automatic generation (Tx) and
         * response (Rx) to Ethernet PAUSE frames.
         * - High water mark should allow for at least two frames to be
         *   received after sending an XOFF.
         * - Low water mark works best when it is very near the high water mark.
         *   This allows the receiver to restart by sending XON when it has
         *   drained a bit. Here we use an arbitrary value of 1500 which will
         *   restart after one full frame is pulled from the buffer. There
         *   could be several smaller frames in the buffer and if so they will
         *   not trigger the XON until their total number reduces the buffer
         *   by 1500.
         * - The pause time is fairly large at 1000 x 512ns = 512 usec.
         */
        const uint16_t rx_buffer_size = (pba & 0xffff) << 10;

        hw->fc.high_water = rx_buffer_size -
            roundup2(sc->hw.mac.max_frame_size, 1024);
        /* 16-byte granularity */
        hw->fc.low_water = hw->fc.high_water - 16;

        if (sc->fc) /* locally set flow control value? */
                hw->fc.requested_mode = sc->fc;
        else
                hw->fc.requested_mode = igc_fc_full;

        hw->fc.pause_time = IGC_FC_PAUSE_TIME;

        hw->fc.send_xon = true;

        /* Issue a global reset */
        igc_reset_hw(hw);
        IGC_WRITE_REG(hw, IGC_WUC, 0);

        /* and a re-init */
        if (igc_init_hw(hw) < 0) {
                aprint_error_dev(sc->sc_dev, "unable to reset hardware\n");
                return;
        }

        /* Setup DMA Coalescing */
        igc_init_dmac(sc, pba);

        IGC_WRITE_REG(hw, IGC_VET, ETHERTYPE_VLAN);
        igc_get_phy_info(hw);
        igc_check_for_link(hw);
}

/*********************************************************************
 *
 *  Initialize the DMA Coalescing feature
 *
 **********************************************************************/
static void
igc_init_dmac(struct igc_softc *sc, uint32_t pba)
{
        struct igc_hw *hw = &sc->hw;
        const uint16_t max_frame_size = sc->hw.mac.max_frame_size;
        uint32_t reg, status;

        if (sc->dmac == 0) { /* Disabling it */
                reg = ~IGC_DMACR_DMAC_EN;       /* XXXRO */
                IGC_WRITE_REG(hw, IGC_DMACR, reg);
                DPRINTF(MISC, "DMA coalescing disabled\n");
                return;
        } else {
                device_printf(sc->sc_dev, "DMA coalescing enabled\n");
        }

        /* Set starting threshold */
        IGC_WRITE_REG(hw, IGC_DMCTXTH, 0);

        uint16_t hwm = 64 * pba - max_frame_size / 16;
        if (hwm < 64 * (pba - 6))
                hwm = 64 * (pba - 6);
        reg = IGC_READ_REG(hw, IGC_FCRTC);
        reg &= ~IGC_FCRTC_RTH_COAL_MASK;
        reg |= (hwm << IGC_FCRTC_RTH_COAL_SHIFT) & IGC_FCRTC_RTH_COAL_MASK;
        IGC_WRITE_REG(hw, IGC_FCRTC, reg);

        uint32_t dmac = pba - max_frame_size / 512;
        if (dmac < pba - 10)
                dmac = pba - 10;
        reg = IGC_READ_REG(hw, IGC_DMACR);
        reg &= ~IGC_DMACR_DMACTHR_MASK;
        reg |= (dmac << IGC_DMACR_DMACTHR_SHIFT) & IGC_DMACR_DMACTHR_MASK;

        /* transition to L0x or L1 if available..*/
        reg |= IGC_DMACR_DMAC_EN | IGC_DMACR_DMAC_LX_MASK;

        /* Check if status is 2.5Gb backplane connection
         * before configuration of watchdog timer, which is
         * in msec values in 12.8usec intervals
         * watchdog timer= msec values in 32usec intervals
         * for non 2.5Gb connection
         */
        status = IGC_READ_REG(hw, IGC_STATUS);
        if ((status & IGC_STATUS_2P5_SKU) &&
            !(status & IGC_STATUS_2P5_SKU_OVER))
                reg |= (sc->dmac * 5) >> 6;
        else
                reg |= sc->dmac >> 5;

        IGC_WRITE_REG(hw, IGC_DMACR, reg);

        IGC_WRITE_REG(hw, IGC_DMCRTRH, 0);

        /* Set the interval before transition */
        reg = IGC_READ_REG(hw, IGC_DMCTLX);
        reg |= IGC_DMCTLX_DCFLUSH_DIS;

        /*
         * in 2.5Gb connection, TTLX unit is 0.4 usec
         * which is 0x4*2 = 0xA. But delay is still 4 usec
         */
        status = IGC_READ_REG(hw, IGC_STATUS);
        if ((status & IGC_STATUS_2P5_SKU) &&
            !(status & IGC_STATUS_2P5_SKU_OVER))
                reg |= 0xA;
        else
                reg |= 0x4;

        IGC_WRITE_REG(hw, IGC_DMCTLX, reg);

        /* free space in tx packet buffer to wake from DMA coal */
        IGC_WRITE_REG(hw, IGC_DMCTXTH,
            (IGC_TXPBSIZE - (2 * max_frame_size)) >> 6);

        /* make low power state decision controlled by DMA coal */
        reg = IGC_READ_REG(hw, IGC_PCIEMISC);
        reg &= ~IGC_PCIEMISC_LX_DECISION;
        IGC_WRITE_REG(hw, IGC_PCIEMISC, reg);
}

static int
igc_setup_interrupts(struct igc_softc *sc)
{
        int error;

        switch (sc->sc_intr_type) {
        case PCI_INTR_TYPE_MSIX:
                error = igc_setup_msix(sc);
                break;
        case PCI_INTR_TYPE_MSI:
                error = igc_setup_msi(sc);
                break;
        case PCI_INTR_TYPE_INTX:
                error = igc_setup_intx(sc);
                break;
        default:
                panic("%s: invalid interrupt type: %d",
                    device_xname(sc->sc_dev), sc->sc_intr_type);
        }

        return error;
}

static void
igc_attach_counters(struct igc_softc *sc)
{
#ifdef IGC_EVENT_COUNTERS

        /* Global counters */
        sc->sc_global_evcnts = kmem_zalloc(
            IGC_GLOBAL_COUNTERS * sizeof(sc->sc_global_evcnts[0]), KM_SLEEP);

        for (int cnt = 0; cnt < IGC_GLOBAL_COUNTERS; cnt++) {
                evcnt_attach_dynamic(&sc->sc_global_evcnts[cnt],
                    igc_global_counters[cnt].type, NULL,
                    device_xname(sc->sc_dev), igc_global_counters[cnt].name);
        }

        /* Driver counters */
        sc->sc_driver_evcnts = kmem_zalloc(
            IGC_DRIVER_COUNTERS * sizeof(sc->sc_driver_evcnts[0]), KM_SLEEP);

        for (int cnt = 0; cnt < IGC_DRIVER_COUNTERS; cnt++) {
                evcnt_attach_dynamic(&sc->sc_driver_evcnts[cnt],
                    igc_driver_counters[cnt].type, NULL,
                    device_xname(sc->sc_dev), igc_driver_counters[cnt].name);
        }

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                q->igcq_driver_counters = kmem_zalloc(
                    IGC_DRIVER_COUNTERS * sizeof(q->igcq_driver_counters[0]),
                    KM_SLEEP);
        }

        /* Queue counters */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                snprintf(q->igcq_queue_evname, sizeof(q->igcq_queue_evname),
                    "%s q%d", device_xname(sc->sc_dev), iq);

                q->igcq_queue_evcnts = kmem_zalloc(
                    IGC_QUEUE_COUNTERS * sizeof(q->igcq_queue_evcnts[0]),
                    KM_SLEEP);

                for (int cnt = 0; cnt < IGC_QUEUE_COUNTERS; cnt++) {
                        evcnt_attach_dynamic(&q->igcq_queue_evcnts[cnt],
                            igc_queue_counters[cnt].type, NULL,
                            q->igcq_queue_evname, igc_queue_counters[cnt].name);
                }
        }

        /* MAC counters */
        snprintf(sc->sc_mac_evname, sizeof(sc->sc_mac_evname),
            "%s Mac Statistics", device_xname(sc->sc_dev));

        sc->sc_mac_evcnts = kmem_zalloc(
            IGC_MAC_COUNTERS * sizeof(sc->sc_mac_evcnts[0]), KM_SLEEP);

        for (int cnt = 0; cnt < IGC_MAC_COUNTERS; cnt++) {
                evcnt_attach_dynamic(&sc->sc_mac_evcnts[cnt], EVCNT_TYPE_MISC,
                    NULL, sc->sc_mac_evname, igc_mac_counters[cnt].name);
        }
#endif
}

static void
igc_detach_counters(struct igc_softc *sc)
{
#ifdef IGC_EVENT_COUNTERS

        /* Global counters */
        for (int cnt = 0; cnt < IGC_GLOBAL_COUNTERS; cnt++)
                evcnt_detach(&sc->sc_global_evcnts[cnt]);

        kmem_free(sc->sc_global_evcnts,
            IGC_GLOBAL_COUNTERS * sizeof(sc->sc_global_evcnts[0]));

        /* Driver counters */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                kmem_free(q->igcq_driver_counters,
                    IGC_DRIVER_COUNTERS * sizeof(q->igcq_driver_counters[0]));
        }

        for (int cnt = 0; cnt < IGC_DRIVER_COUNTERS; cnt++)
                evcnt_detach(&sc->sc_driver_evcnts[cnt]);

        kmem_free(sc->sc_driver_evcnts,
            IGC_DRIVER_COUNTERS * sizeof(sc->sc_driver_evcnts[0]));

        /* Queue counters */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                for (int cnt = 0; cnt < IGC_QUEUE_COUNTERS; cnt++)
                        evcnt_detach(&q->igcq_queue_evcnts[cnt]);

                kmem_free(q->igcq_queue_evcnts,
                    IGC_QUEUE_COUNTERS * sizeof(q->igcq_queue_evcnts[0]));
        }

        /* MAC statistics */
        for (int cnt = 0; cnt < IGC_MAC_COUNTERS; cnt++)
                evcnt_detach(&sc->sc_mac_evcnts[cnt]);

        kmem_free(sc->sc_mac_evcnts,
            IGC_MAC_COUNTERS * sizeof(sc->sc_mac_evcnts[0]));
#endif
}

/*
 * XXX
 * FreeBSD uses 4-byte-wise read for 64-bit counters, while Linux just
 * drops hi words.
 */
static inline uint64_t __unused
igc_read_mac_counter(struct igc_hw *hw, bus_size_t reg, bool is64)
{
        uint64_t val;

        val = IGC_READ_REG(hw, reg);
        if (is64)
                val += ((uint64_t)IGC_READ_REG(hw, reg + 4)) << 32;
        return val;
}

static void
igc_update_counters(struct igc_softc *sc)
{
#ifdef IGC_EVENT_COUNTERS

        /* Global counters: nop */

        /* Driver counters */
        uint64_t sum[IGC_DRIVER_COUNTERS];

        memset(sum, 0, sizeof(sum));
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                for (int cnt = 0; cnt < IGC_DRIVER_COUNTERS; cnt++) {
                        sum[cnt] += IGC_QUEUE_DRIVER_COUNTER_VAL(q, cnt);
                        IGC_QUEUE_DRIVER_COUNTER_STORE(q, cnt, 0);
                }
        }

        for (int cnt = 0; cnt < IGC_DRIVER_COUNTERS; cnt++)
                IGC_DRIVER_COUNTER_ADD(sc, cnt, sum[cnt]);

        /* Queue counters: nop */

        /* Mac statistics */
        struct igc_hw *hw = &sc->hw;
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        uint64_t iqdrops = 0;

        for (int cnt = 0; cnt < IGC_MAC_COUNTERS; cnt++) {
                uint64_t val;
                bus_size_t regaddr = igc_mac_counters[cnt].reg;

                val = igc_read_mac_counter(hw, regaddr,
                    igc_mac_counters[cnt].is64);
                IGC_MAC_COUNTER_ADD(sc, cnt, val);
                /* XXX Count MPC to iqdrops. */
                if (regaddr == IGC_MPC)
                        iqdrops += val;
        }

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                uint32_t val;

                /* XXX RQDPC should be visible via evcnt(9). */
                val = IGC_READ_REG(hw, IGC_RQDPC(iq));

                /* RQDPC is not cleard on read. */
                if (val != 0)
                        IGC_WRITE_REG(hw, IGC_RQDPC(iq), 0);
                iqdrops += val;
        }

        if (iqdrops != 0)
                if_statadd(ifp, if_iqdrops, iqdrops);
#endif
}

static void
igc_clear_counters(struct igc_softc *sc)
{
#ifdef IGC_EVENT_COUNTERS

        /* Global counters */
        for (int cnt = 0; cnt < IGC_GLOBAL_COUNTERS; cnt++)
                IGC_GLOBAL_COUNTER_STORE(sc, cnt, 0);

        /* Driver counters */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                for (int cnt = 0; cnt < IGC_DRIVER_COUNTERS; cnt++)
                        IGC_QUEUE_DRIVER_COUNTER_STORE(q, cnt, 0);
        }

        for (int cnt = 0; cnt < IGC_DRIVER_COUNTERS; cnt++)
                IGC_DRIVER_COUNTER_STORE(sc, cnt, 0);

        /* Queue counters */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                for (int cnt = 0; cnt < IGC_QUEUE_COUNTERS; cnt++)
                        IGC_QUEUE_COUNTER_STORE(q, cnt, 0);
        }

        /* Mac statistics */
        struct igc_hw *hw = &sc->hw;

        for (int cnt = 0; cnt < IGC_MAC_COUNTERS; cnt++) {
                (void)igc_read_mac_counter(hw, igc_mac_counters[cnt].reg,
                    igc_mac_counters[cnt].is64);
                IGC_MAC_COUNTER_STORE(sc, cnt, 0);
        }
#endif
}

static int
igc_setup_msix(struct igc_softc *sc)
{
        pci_chipset_tag_t pc = sc->osdep.os_pa.pa_pc;
        device_t dev = sc->sc_dev;
        pci_intr_handle_t *intrs;
        void **ihs;
        const char *intrstr;
        char intrbuf[PCI_INTRSTR_LEN];
        char xnamebuf[MAX(32, MAXCOMLEN)];
        int iq, error;

        for (iq = 0, intrs = sc->sc_intrs, ihs = sc->sc_ihs;
            iq < sc->sc_nqueues; iq++, intrs++, ihs++) {
                struct igc_queue *q = &sc->queues[iq];

                snprintf(xnamebuf, sizeof(xnamebuf), "%s: txrx %d",
                    device_xname(dev), iq);

                intrstr = pci_intr_string(pc, *intrs, intrbuf, sizeof(intrbuf));

                pci_intr_setattr(pc, intrs, PCI_INTR_MPSAFE, true);
                *ihs = pci_intr_establish_xname(pc, *intrs, IPL_NET,
                    igc_intr_queue, q, xnamebuf);
                if (*ihs == NULL) {
                        aprint_error_dev(dev,
                            "unable to establish txrx interrupt at %s\n",
                            intrstr);
                        return ENOBUFS;
                }
                aprint_normal_dev(dev, "txrx interrupting at %s\n", intrstr);

                kcpuset_t *affinity;
                kcpuset_create(&affinity, true);
                kcpuset_set(affinity, iq % ncpu);
                error = interrupt_distribute(*ihs, affinity, NULL);
                if (error) {
                        aprint_normal_dev(dev,
                            "%s: unable to change affinity, use default CPU\n",
                            intrstr);
                }
                kcpuset_destroy(affinity);

                q->igcq_si = softint_establish(SOFTINT_NET | SOFTINT_MPSAFE,
                    igc_handle_queue, q);
                if (q->igcq_si == NULL) {
                        aprint_error_dev(dev,
                            "%s: unable to establish softint\n", intrstr);
                        return ENOBUFS;
                }

                q->msix = iq;
                q->eims = 1 << iq;
        }

        snprintf(xnamebuf, MAXCOMLEN, "%s_tx_rx", device_xname(dev));
        error = workqueue_create(&sc->sc_queue_wq, xnamebuf,
            igc_handle_queue_work, sc, IGC_WORKQUEUE_PRI, IPL_NET,
            WQ_PERCPU | WQ_MPSAFE);
        if (error) {
                aprint_error_dev(dev, "workqueue_create failed\n");
                return ENOBUFS;
        }
        sc->sc_txrx_workqueue = false;

        intrstr = pci_intr_string(pc, *intrs, intrbuf, sizeof(intrbuf));
        snprintf(xnamebuf, sizeof(xnamebuf), "%s: link", device_xname(dev));
        pci_intr_setattr(pc, intrs, PCI_INTR_MPSAFE, true);
        *ihs = pci_intr_establish_xname(pc, *intrs, IPL_NET,
            igc_intr_link, sc, xnamebuf);
        if (*ihs == NULL) {
                aprint_error_dev(dev,
                    "unable to establish link interrupt at %s\n", intrstr);
                return ENOBUFS;
        }
        aprint_normal_dev(dev, "link interrupting at %s\n", intrstr);
        /* use later in igc_configure_queues() */
        sc->linkvec = iq;

        return 0;
}

static int
igc_setup_msi(struct igc_softc *sc)
{
        pci_chipset_tag_t pc = sc->osdep.os_pa.pa_pc;
        device_t dev = sc->sc_dev;
        pci_intr_handle_t *intr = sc->sc_intrs;
        void **ihs = sc->sc_ihs;
        const char *intrstr;
        char intrbuf[PCI_INTRSTR_LEN];
        char xnamebuf[MAX(32, MAXCOMLEN)];
        int error;

        intrstr = pci_intr_string(pc, *intr, intrbuf, sizeof(intrbuf));

        snprintf(xnamebuf, sizeof(xnamebuf), "%s: msi", device_xname(dev));
        pci_intr_setattr(pc, intr, PCI_INTR_MPSAFE, true);
        *ihs = pci_intr_establish_xname(pc, *intr, IPL_NET,
            igc_intr, sc, xnamebuf);
        if (*ihs == NULL) {
                aprint_error_dev(dev,
                    "unable to establish interrupt at %s\n", intrstr);
                return ENOBUFS;
        }
        aprint_normal_dev(dev, "interrupting at %s\n", intrstr);

        struct igc_queue *iq = sc->queues;
        iq->igcq_si = softint_establish(SOFTINT_NET | SOFTINT_MPSAFE,
            igc_handle_queue, iq);
        if (iq->igcq_si == NULL) {
                aprint_error_dev(dev,
                    "%s: unable to establish softint\n", intrstr);
                return ENOBUFS;
        }

        snprintf(xnamebuf, MAXCOMLEN, "%s_tx_rx", device_xname(dev));
        error = workqueue_create(&sc->sc_queue_wq, xnamebuf,
            igc_handle_queue_work, sc, IGC_WORKQUEUE_PRI, IPL_NET,
            WQ_PERCPU | WQ_MPSAFE);
        if (error) {
                aprint_error_dev(dev, "workqueue_create failed\n");
                return ENOBUFS;
        }
        sc->sc_txrx_workqueue = false;

        sc->queues[0].msix = 0;
        sc->linkvec = 0;

        return 0;
}

static int
igc_setup_intx(struct igc_softc *sc)
{
        pci_chipset_tag_t pc = sc->osdep.os_pa.pa_pc;
        device_t dev = sc->sc_dev;
        pci_intr_handle_t *intr = sc->sc_intrs;
        void **ihs = sc->sc_ihs;
        const char *intrstr;
        char intrbuf[PCI_INTRSTR_LEN];
        char xnamebuf[32];

        intrstr = pci_intr_string(pc, *intr, intrbuf, sizeof(intrbuf));

        snprintf(xnamebuf, sizeof(xnamebuf), "%s:intx", device_xname(dev));
        pci_intr_setattr(pc, intr, PCI_INTR_MPSAFE, true);
        *ihs = pci_intr_establish_xname(pc, *intr, IPL_NET,
            igc_intr, sc, xnamebuf);
        if (*ihs == NULL) {
                aprint_error_dev(dev,
                    "unable to establish interrupt at %s\n", intrstr);
                return ENOBUFS;
        }
        aprint_normal_dev(dev, "interrupting at %s\n", intrstr);

        struct igc_queue *iq = sc->queues;
        iq->igcq_si = softint_establish(SOFTINT_NET | SOFTINT_MPSAFE,
            igc_handle_queue, iq);
        if (iq->igcq_si == NULL) {
                aprint_error_dev(dev,
                    "%s: unable to establish softint\n", intrstr);
                return ENOBUFS;
        }

        /* create workqueue? */
        sc->sc_txrx_workqueue = false;

        sc->queues[0].msix = 0;
        sc->linkvec = 0;

        return 0;
}

static int
igc_dma_malloc(struct igc_softc *sc, bus_size_t size, struct igc_dma_alloc *dma)
{
        struct igc_osdep *os = &sc->osdep;

        dma->dma_tag = os->os_dmat;

        if (bus_dmamap_create(dma->dma_tag, size, 1, size, 0,
            BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW, &dma->dma_map))
                return 1;
        if (bus_dmamem_alloc(dma->dma_tag, size, PAGE_SIZE, 0, &dma->dma_seg,
            1, &dma->dma_nseg, BUS_DMA_WAITOK))
                goto destroy;
        /*
         * XXXRO
         *
         * Coherent mapping for descriptors is required for now.
         *
         * Both TX and RX descriptors are 16-byte length, which is shorter
         * than dcache lines on modern CPUs. Therefore, sync for a descriptor
         * may overwrite DMA read for descriptors in the same cache line.
         *
         * Can't we avoid this by use cache-line-aligned descriptors at once?
         */
        if (bus_dmamem_map(dma->dma_tag, &dma->dma_seg, dma->dma_nseg, size,
            &dma->dma_vaddr, BUS_DMA_WAITOK | BUS_DMA_COHERENT /* XXXRO */))
                goto free;
        if (bus_dmamap_load(dma->dma_tag, dma->dma_map, dma->dma_vaddr, size,
            NULL, BUS_DMA_WAITOK))
                goto unmap;

        dma->dma_size = size;

        return 0;
 unmap:
        bus_dmamem_unmap(dma->dma_tag, dma->dma_vaddr, size);
 free:
        bus_dmamem_free(dma->dma_tag, &dma->dma_seg, dma->dma_nseg);
 destroy:
        bus_dmamap_destroy(dma->dma_tag, dma->dma_map);
        dma->dma_map = NULL;
        dma->dma_tag = NULL;
        return 1;
}

static void
igc_dma_free(struct igc_softc *sc, struct igc_dma_alloc *dma)
{

        if (dma->dma_tag == NULL)
                return;

        if (dma->dma_map != NULL) {
                bus_dmamap_sync(dma->dma_tag, dma->dma_map, 0,
                    dma->dma_map->dm_mapsize,
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(dma->dma_tag, dma->dma_map);
                bus_dmamem_unmap(dma->dma_tag, dma->dma_vaddr, dma->dma_size);
                bus_dmamem_free(dma->dma_tag, &dma->dma_seg, dma->dma_nseg);
                bus_dmamap_destroy(dma->dma_tag, dma->dma_map);
                dma->dma_map = NULL;
        }
}

/*********************************************************************
 *
 *  Setup networking device structure and register an interface.
 *
 **********************************************************************/
static void
igc_setup_interface(struct igc_softc *sc)
{
        struct ifnet *ifp = &sc->sc_ec.ec_if;

        strlcpy(ifp->if_xname, device_xname(sc->sc_dev), sizeof(ifp->if_xname));
        ifp->if_softc = sc;
        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_extflags = IFEF_MPSAFE;
        ifp->if_ioctl = igc_ioctl;
        ifp->if_start = igc_start;
        if (sc->sc_nqueues > 1)
                ifp->if_transmit = igc_transmit;
        ifp->if_watchdog = igc_watchdog;
        ifp->if_init = igc_init;
        ifp->if_stop = igc_stop;

        ifp->if_capabilities = IFCAP_TSOv4 | IFCAP_TSOv6;

        ifp->if_capabilities |=
            IFCAP_CSUM_IPv4_Tx  | IFCAP_CSUM_IPv4_Rx  |
            IFCAP_CSUM_TCPv4_Tx | IFCAP_CSUM_TCPv4_Rx |
            IFCAP_CSUM_UDPv4_Tx | IFCAP_CSUM_UDPv4_Rx |
            IFCAP_CSUM_TCPv6_Tx | IFCAP_CSUM_TCPv6_Rx |
            IFCAP_CSUM_UDPv6_Tx | IFCAP_CSUM_UDPv6_Rx;

        ifp->if_capenable = 0;

        sc->sc_ec.ec_capabilities |=
            ETHERCAP_JUMBO_MTU | ETHERCAP_VLAN_MTU;

        IFQ_SET_MAXLEN(&ifp->if_snd, sc->num_tx_desc - 1);
        IFQ_SET_READY(&ifp->if_snd);

#if NVLAN > 0
        sc->sc_ec.ec_capabilities |=  ETHERCAP_VLAN_HWTAGGING;
#endif

        mutex_init(&sc->sc_core_lock, MUTEX_DEFAULT, IPL_NET);

        /* Initialize ifmedia structures. */
        sc->sc_ec.ec_ifmedia = &sc->media;
        ifmedia_init_with_lock(&sc->media, IFM_IMASK, igc_media_change,
            igc_media_status, &sc->sc_core_lock);
        ifmedia_add(&sc->media, IFM_ETHER | IFM_10_T, 0, NULL);
        ifmedia_add(&sc->media, IFM_ETHER | IFM_10_T | IFM_FDX, 0, NULL);
        ifmedia_add(&sc->media, IFM_ETHER | IFM_100_TX, 0, NULL);
        ifmedia_add(&sc->media, IFM_ETHER | IFM_100_TX | IFM_FDX, 0, NULL);
        ifmedia_add(&sc->media, IFM_ETHER | IFM_1000_T | IFM_FDX, 0, NULL);
        ifmedia_add(&sc->media, IFM_ETHER | IFM_2500_T | IFM_FDX, 0, NULL);
        ifmedia_add(&sc->media, IFM_ETHER | IFM_AUTO, 0, NULL);
        ifmedia_set(&sc->media, IFM_ETHER | IFM_AUTO);

        sc->sc_rx_intr_process_limit = IGC_RX_INTR_PROCESS_LIMIT_DEFAULT;
        sc->sc_tx_intr_process_limit = IGC_TX_INTR_PROCESS_LIMIT_DEFAULT;
        sc->sc_rx_process_limit = IGC_RX_PROCESS_LIMIT_DEFAULT;
        sc->sc_tx_process_limit = IGC_TX_PROCESS_LIMIT_DEFAULT;

        if_initialize(ifp);
        sc->sc_ipq = if_percpuq_create(ifp);
        if_deferred_start_init(ifp, NULL);
        ether_ifattach(ifp, sc->hw.mac.addr);
        ether_set_ifflags_cb(&sc->sc_ec, igc_ifflags_cb);
        if_register(ifp);
}

static int
igc_init(struct ifnet *ifp)
{
        struct igc_softc *sc = ifp->if_softc;
        int error;

        mutex_enter(&sc->sc_core_lock);
        error = igc_init_locked(sc);
        mutex_exit(&sc->sc_core_lock);

        return error;
}

static int
igc_init_locked(struct igc_softc *sc)
{
        struct ethercom *ec = &sc->sc_ec;
        struct ifnet *ifp = &ec->ec_if;

        DPRINTF(CFG, "called\n");

        KASSERT(mutex_owned(&sc->sc_core_lock));

        if (ISSET(ifp->if_flags, IFF_RUNNING))
                igc_stop_locked(sc);

        /* Put the address into the receive address array. */
        igc_rar_set(&sc->hw, sc->hw.mac.addr, 0);

        /* Initialize the hardware. */
        igc_reset(sc);
        igc_update_link_status(sc);

        /* Setup VLAN support, basic and offload if available. */
        IGC_WRITE_REG(&sc->hw, IGC_VET, ETHERTYPE_VLAN);

        igc_initialize_transmit_unit(sc);
        igc_initialize_receive_unit(sc);

        if (ec->ec_capenable & ETHERCAP_VLAN_HWTAGGING) {
                uint32_t ctrl = IGC_READ_REG(&sc->hw, IGC_CTRL);
                ctrl |= IGC_CTRL_VME;
                IGC_WRITE_REG(&sc->hw, IGC_CTRL, ctrl);
        }

        /* Setup multicast table. */
        igc_set_filter(sc);

        igc_clear_hw_cntrs_base_generic(&sc->hw);

        if (sc->sc_intr_type == PCI_INTR_TYPE_MSIX)
                igc_configure_queues(sc);

        /* This clears any pending interrupts */
        IGC_READ_REG(&sc->hw, IGC_ICR);
        IGC_WRITE_REG(&sc->hw, IGC_ICS, IGC_ICS_LSC);

        /* The driver can now take control from firmware. */
        igc_get_hw_control(sc);

        /* Set Energy Efficient Ethernet. */
        igc_set_eee_i225(&sc->hw, true, true, true);

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];

                mutex_enter(&rxr->rxr_lock);
                igc_rxfill(rxr);
                mutex_exit(&rxr->rxr_lock);
        }

        sc->sc_core_stopping = false;

        ifp->if_flags |= IFF_RUNNING;

        /* Save last flags for the callback */
        sc->sc_if_flags = ifp->if_flags;

        callout_schedule(&sc->sc_tick_ch, hz);

        igc_enable_intr(sc);

        return 0;
}

static inline int
igc_load_mbuf(struct igc_queue *q, bus_dma_tag_t dmat, bus_dmamap_t map,
    struct mbuf *m)
{
        int error;

        error = bus_dmamap_load_mbuf(dmat, map, m,
            BUS_DMA_WRITE | BUS_DMA_NOWAIT);

        if (__predict_false(error == EFBIG)) {
                IGC_DRIVER_EVENT(q, txdma_efbig, 1);
                m = m_defrag(m, M_NOWAIT);
                if (__predict_false(m == NULL)) {
                        IGC_DRIVER_EVENT(q, txdma_defrag, 1);
                        return ENOBUFS;
                }
                error = bus_dmamap_load_mbuf(dmat, map, m,
                    BUS_DMA_WRITE | BUS_DMA_NOWAIT);
        }

        switch (error) {
        case 0:
                break;
        case ENOMEM:
                IGC_DRIVER_EVENT(q, txdma_enomem, 1);
                break;
        case EINVAL:
                IGC_DRIVER_EVENT(q, txdma_einval, 1);
                break;
        case EAGAIN:
                IGC_DRIVER_EVENT(q, txdma_eagain, 1);
                break;
        default:
                IGC_DRIVER_EVENT(q, txdma_other, 1);
                break;
        }

        return error;
}

#define IGC_TX_START    1
#define IGC_TX_TRANSMIT 2

static void
igc_start(struct ifnet *ifp)
{
        struct igc_softc *sc = ifp->if_softc;

        if (__predict_false(!sc->link_active)) {
                IFQ_PURGE(&ifp->if_snd);
                return;
        }

        struct tx_ring *txr = &sc->tx_rings[0]; /* queue 0 */
        mutex_enter(&txr->txr_lock);
        igc_tx_common_locked(ifp, txr, IGC_TX_START);
        mutex_exit(&txr->txr_lock);
}

static inline u_int
igc_select_txqueue(struct igc_softc *sc, struct mbuf *m __unused)
{
        const u_int cpuid = cpu_index(curcpu());

        return cpuid % sc->sc_nqueues;
}

static int
igc_transmit(struct ifnet *ifp, struct mbuf *m)
{
        struct igc_softc *sc = ifp->if_softc;
        const u_int qid = igc_select_txqueue(sc, m);
        struct tx_ring *txr = &sc->tx_rings[qid];
        struct igc_queue *q = txr->txr_igcq;

        if (__predict_false(!pcq_put(txr->txr_interq, m))) {
                IGC_QUEUE_EVENT(q, tx_pcq_drop, 1);
                m_freem(m);
                return ENOBUFS;
        }

        mutex_enter(&txr->txr_lock);
        igc_tx_common_locked(ifp, txr, IGC_TX_TRANSMIT);
        mutex_exit(&txr->txr_lock);

        return 0;
}

static void
igc_tx_common_locked(struct ifnet *ifp, struct tx_ring *txr, int caller)
{
        struct igc_softc *sc = ifp->if_softc;
        struct igc_queue *q = txr->txr_igcq;
        net_stat_ref_t nsr = IF_STAT_GETREF(ifp);
        int prod, free, last = -1;
        bool post = false;

        prod = txr->next_avail_desc;
        free = txr->next_to_clean;
        if (free <= prod)
                free += sc->num_tx_desc;
        free -= prod;

        DPRINTF(TX, "%s: begin: msix %d prod %d n2c %d free %d\n",
            caller == IGC_TX_TRANSMIT ? "transmit" : "start",
            txr->me, prod, txr->next_to_clean, free);

        for (;;) {
                struct mbuf *m;

                if (__predict_false(free <= IGC_MAX_SCATTER)) {
                        IGC_QUEUE_EVENT(q, tx_no_desc, 1);
                        break;
                }

                if (caller == IGC_TX_TRANSMIT)
                        m = pcq_get(txr->txr_interq);
                else
                        IFQ_DEQUEUE(&ifp->if_snd, m);
                if (__predict_false(m == NULL))
                        break;

                struct igc_tx_buf *txbuf = &txr->tx_buffers[prod];
                bus_dmamap_t map = txbuf->map;

                if (__predict_false(
                    igc_load_mbuf(q, txr->txdma.dma_tag, map, m))) {
                        if (caller == IGC_TX_TRANSMIT)
                                IGC_QUEUE_EVENT(q, tx_pcq_drop, 1);
                        m_freem(m);
                        if_statinc_ref(ifp, nsr, if_oerrors);
                        continue;
                }

                uint32_t ctx_cmd_type_len = 0, olinfo_status = 0;
                if (igc_tx_ctx_setup(txr, m, prod, &ctx_cmd_type_len,
                    &olinfo_status)) {
                        IGC_QUEUE_EVENT(q, tx_ctx, 1);
                        /* Consume the first descriptor */
                        prod = igc_txdesc_incr(sc, prod);
                        free--;
                }

                bus_dmamap_sync(txr->txdma.dma_tag, map, 0,
                    map->dm_mapsize, BUS_DMASYNC_PREWRITE);

                for (int i = 0; i < map->dm_nsegs; i++) {
                        union igc_adv_tx_desc *txdesc = &txr->tx_base[prod];

                        uint32_t cmd_type_len = ctx_cmd_type_len |
                            IGC_ADVTXD_DCMD_IFCS | IGC_ADVTXD_DTYP_DATA |
                            IGC_ADVTXD_DCMD_DEXT | map->dm_segs[i].ds_len;
                        if (i == map->dm_nsegs - 1) {
                                cmd_type_len |=
                                    IGC_ADVTXD_DCMD_EOP | IGC_ADVTXD_DCMD_RS;
                        }

                        igc_txdesc_sync(txr, prod,
                            BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                        htolem64(&txdesc->read.buffer_addr,
                            map->dm_segs[i].ds_addr);
                        htolem32(&txdesc->read.cmd_type_len, cmd_type_len);
                        htolem32(&txdesc->read.olinfo_status, olinfo_status);
                        igc_txdesc_sync(txr, prod,
                            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

                        last = prod;
                        prod = igc_txdesc_incr(sc, prod);
                }

                txbuf->m_head = m;
                txbuf->eop_index = last;

                bpf_mtap(ifp, m, BPF_D_OUT);

                if_statadd_ref(ifp, nsr, if_obytes, m->m_pkthdr.len);
                if (m->m_flags & M_MCAST)
                        if_statinc_ref(ifp, nsr, if_omcasts);
                IGC_QUEUE_EVENT(q, tx_packets, 1);
                IGC_QUEUE_EVENT(q, tx_bytes, m->m_pkthdr.len);

                free -= map->dm_nsegs;
                post = true;
        }

        if (post) {
                txr->next_avail_desc = prod;
                IGC_WRITE_REG(&sc->hw, IGC_TDT(txr->me), prod);
        }

        DPRINTF(TX, "%s: done : msix %d prod %d n2c %d free %d\n",
            caller == IGC_TX_TRANSMIT ? "transmit" : "start",
            txr->me, prod, txr->next_to_clean, free);

        IF_STAT_PUTREF(ifp);
}

static bool
igc_txeof(struct tx_ring *txr, u_int limit)
{
        struct igc_softc *sc = txr->sc;
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        int cons, prod;
        bool more = false;

        prod = txr->next_avail_desc;
        cons = txr->next_to_clean;

        if (cons == prod) {
                DPRINTF(TX, "false: msix %d cons %d prod %d\n",
                    txr->me, cons, prod);
                return false;
        }

        do {
                struct igc_tx_buf *txbuf = &txr->tx_buffers[cons];
                const int last = txbuf->eop_index;

                membar_consumer();      /* XXXRO necessary? */

                KASSERT(last != -1);
                union igc_adv_tx_desc *txdesc = &txr->tx_base[last];
                igc_txdesc_sync(txr, last, BUS_DMASYNC_POSTREAD);
                const uint32_t status = le32toh(txdesc->wb.status);
                igc_txdesc_sync(txr, last, BUS_DMASYNC_PREREAD);

                if (!(status & IGC_TXD_STAT_DD))
                        break;

                if (limit-- == 0) {
                        more = true;
                        DPRINTF(TX, "pending TX "
                            "msix %d cons %d last %d prod %d "
                            "status 0x%08x\n",
                            txr->me, cons, last, prod, status);
                        break;
                }

                DPRINTF(TX, "handled TX "
                    "msix %d cons %d last %d prod %d "
                    "status 0x%08x\n",
                    txr->me, cons, last, prod, status);

                if_statinc(ifp, if_opackets);

                bus_dmamap_t map = txbuf->map;
                bus_dmamap_sync(txr->txdma.dma_tag, map, 0, map->dm_mapsize,
                    BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(txr->txdma.dma_tag, map);
                m_freem(txbuf->m_head);

                txbuf->m_head = NULL;
                txbuf->eop_index = -1;

                cons = igc_txdesc_incr(sc, last);
        } while (cons != prod);

        txr->next_to_clean = cons;

        return more;
}

static void
igc_intr_barrier(struct igc_softc *sc __unused)
{

        xc_barrier(0);
}

static void
igc_stop(struct ifnet *ifp, int disable)
{
        struct igc_softc *sc = ifp->if_softc;

        mutex_enter(&sc->sc_core_lock);
        igc_stop_locked(sc);
        mutex_exit(&sc->sc_core_lock);
}

/*********************************************************************
 *
 *  This routine disables all traffic on the adapter by issuing a
 *  global reset on the MAC.
 *
 **********************************************************************/
static void
igc_stop_locked(struct igc_softc *sc)
{
        struct ifnet *ifp = &sc->sc_ec.ec_if;

        DPRINTF(CFG, "called\n");

        KASSERT(mutex_owned(&sc->sc_core_lock));

        /*
         * If stopping processing has already started, do nothing.
         */
        if ((ifp->if_flags & IFF_RUNNING) == 0)
                return;

        /* Tell the stack that the interface is no longer active. */
        ifp->if_flags &= ~IFF_RUNNING;

        /*
         * igc_handle_queue() can enable interrupts, so wait for completion of
         * last igc_handle_queue() after unset IFF_RUNNING.
         */
        mutex_exit(&sc->sc_core_lock);
        igc_barrier_handle_queue(sc);
        mutex_enter(&sc->sc_core_lock);

        sc->sc_core_stopping = true;

        igc_disable_intr(sc);

        callout_halt(&sc->sc_tick_ch, &sc->sc_core_lock);

        igc_reset_hw(&sc->hw);
        IGC_WRITE_REG(&sc->hw, IGC_WUC, 0);

        /*
         * Wait for completion of interrupt handlers.
         */
        mutex_exit(&sc->sc_core_lock);
        igc_intr_barrier(sc);
        mutex_enter(&sc->sc_core_lock);

        igc_update_link_status(sc);

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct tx_ring *txr = &sc->tx_rings[iq];

                igc_withdraw_transmit_packets(txr, false);
        }

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];

                callout_halt(&rxr->rx_refill, &rxr->rxr_lock);
                igc_clear_receive_status(rxr);
        }

        /* Save last flags for the callback */
        sc->sc_if_flags = ifp->if_flags;
}

/*********************************************************************
 *  Ioctl entry point
 *
 *  igc_ioctl is called when the user wants to configure the
 *  interface.
 *
 *  return 0 on success, positive on failure
 **********************************************************************/
static int
igc_ioctl(struct ifnet * ifp, u_long cmd, void *data)
{
        struct igc_softc *sc __unused = ifp->if_softc;
        int s;
        int error;

        DPRINTF(CFG, "cmd 0x%016lx\n", cmd);

        switch (cmd) {
        case SIOCADDMULTI:
        case SIOCDELMULTI:
                break;
        default:
                KASSERT(IFNET_LOCKED(ifp));
        }

        if (cmd == SIOCZIFDATA) {
                mutex_enter(&sc->sc_core_lock);
                igc_clear_counters(sc);
                mutex_exit(&sc->sc_core_lock);
        }

        switch (cmd) {
#ifdef IF_RXR
        case SIOCGIFRXR:
                s = splnet();
                error = igc_rxrinfo(sc, (struct if_rxrinfo *)ifr->ifr_data);
                splx(s);
                break;
#endif
        default:
                s = splnet();
                error = ether_ioctl(ifp, cmd, data);
                splx(s);
                break;
        }

        if (error != ENETRESET)
                return error;

        error = 0;

        if (cmd == SIOCSIFCAP)
                error = if_init(ifp);
        else if ((cmd == SIOCADDMULTI) || (cmd == SIOCDELMULTI)) {
                mutex_enter(&sc->sc_core_lock);
                if (sc->sc_if_flags & IFF_RUNNING) {
                        /*
                         * Multicast list has changed; set the hardware filter
                         * accordingly.
                         */
                        igc_disable_intr(sc);
                        igc_set_filter(sc);
                        igc_enable_intr(sc);
                }
                mutex_exit(&sc->sc_core_lock);
        }

        return error;
}

#ifdef IF_RXR
static int
igc_rxrinfo(struct igc_softc *sc, struct if_rxrinfo *ifri)
{
        struct if_rxring_info *ifr, ifr1;
        int error;

        if (sc->sc_nqueues > 1) {
                ifr = kmem_zalloc(sc->sc_nqueues * sizeof(*ifr), KM_SLEEP);
        } else {
                ifr = &ifr1;
                memset(ifr, 0, sizeof(*ifr));
        }

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];

                ifr[iq].ifr_size = MCLBYTES;
                snprintf(ifr[iq].ifr_name, sizeof(ifr[iq].ifr_name), "%d", iq);
                ifr[iq].ifr_info = rxr->rx_ring;
        }

        error = if_rxr_info_ioctl(ifri, sc->sc_nqueues, ifr);
        if (sc->sc_nqueues > 1)
                kmem_free(ifr, sc->sc_nqueues * sizeof(*ifr));

        return error;
}
#endif

static void
igc_rxfill(struct rx_ring *rxr)
{
        struct igc_softc *sc = rxr->sc;
        int id;

        for (id = 0; id < sc->num_rx_desc; id++) {
                if (igc_get_buf(rxr, id, false)) {
                        panic("%s: msix=%d i=%d\n", __func__, rxr->me, id);
                }
        }

        id = sc->num_rx_desc - 1;
        rxr->last_desc_filled = id;
        IGC_WRITE_REG(&sc->hw, IGC_RDT(rxr->me), id);
        rxr->next_to_check = 0;
}

static bool
igc_rxrefill(struct rx_ring *rxr)
{
        struct igc_softc *sc = rxr->sc;
        int id;
        const int start = igc_rxdesc_incr(sc, rxr->last_desc_filled);
        bool progress = false;

        for (id = start; id != rxr->next_to_check; id = igc_rxdesc_incr(sc, id)) {
                if (igc_get_buf(rxr, id, true))
                        break;
                progress = true;
        }

        if (progress) {
                int last = igc_rxdesc_decr(sc, id);
                DPRINTF(RX, "%s RDT %d last%d\n",
                        rxr->last_desc_filled == last ? "same" : "diff",
                        rxr->last_desc_filled, last);
                rxr->last_desc_filled = last;
                IGC_WRITE_REG(&sc->hw, IGC_RDT(rxr->me), last);
        }

        return id != rxr->next_to_check;
}

static void
igc_rxrefill_callout(void *callout_arg)
{
        struct rx_ring *rxr = callout_arg;

        mutex_enter(&rxr->rxr_lock);
        if (igc_rxrefill(rxr))
                callout_schedule(&rxr->rx_refill, 1);
        mutex_exit(&rxr->rxr_lock);
}

/*********************************************************************
 *
 *  This routine executes in interrupt context. It replenishes
 *  the mbufs in the descriptor and sends data which has been
 *  dma'ed into host memory to upper layer.
 *
 *********************************************************************/
static bool
igc_rxeof(struct rx_ring *rxr, u_int limit)
{
        struct igc_softc *sc = rxr->sc;
        struct igc_queue *q = rxr->rxr_igcq;
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        int id;
        bool more = false;

        id = rxr->next_to_check;
        for (;;) {
                union igc_adv_rx_desc *rxdesc = &rxr->rx_base[id];
                struct igc_rx_buf *rxbuf, *nxbuf;
                struct mbuf *mp, *m;

                igc_rxdesc_sync(rxr, id,
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);

                const uint32_t staterr = le32toh(rxdesc->wb.upper.status_error);

                if (!ISSET(staterr, IGC_RXD_STAT_DD)) {
                        igc_rxdesc_sync(rxr, id,
                            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
                        break;
                }

                if (limit-- == 0) {
                        igc_rxdesc_sync(rxr, id,
                            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
                        DPRINTF(RX, "more=true\n");
                        more = true;
                        break;
                }

                /* Zero out the receive descriptors status. */
                rxdesc->wb.upper.status_error = 0;

                /* Pull the mbuf off the ring. */
                rxbuf = &rxr->rx_buffers[id];
                bus_dmamap_t map = rxbuf->map;
                bus_dmamap_sync(rxr->rxdma.dma_tag, map,
                    0, map->dm_mapsize, BUS_DMASYNC_POSTREAD);
                bus_dmamap_unload(rxr->rxdma.dma_tag, map);

                mp = rxbuf->buf;
                rxbuf->buf = NULL;

                const bool eop = staterr & IGC_RXD_STAT_EOP;
                const uint16_t len = le16toh(rxdesc->wb.upper.length);

#if NVLAN > 0
                const uint16_t vtag = le16toh(rxdesc->wb.upper.vlan);
#endif

                const uint32_t ptype = le32toh(rxdesc->wb.lower.lo_dword.data) &
                    IGC_PKTTYPE_MASK;

                const uint32_t hash __unused =
                    le32toh(rxdesc->wb.lower.hi_dword.rss);
                const uint16_t hashtype __unused =
                    le16toh(rxdesc->wb.lower.lo_dword.hs_rss.pkt_info) &
                    IGC_RXDADV_RSSTYPE_MASK;

                igc_rxdesc_sync(rxr, id,
                    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

                if (__predict_false(staterr & IGC_RXDEXT_STATERR_RXE)) {
                        m_freem(rxbuf->fmp);
                        rxbuf->fmp = NULL;

                        m_freem(mp);
                        m = NULL;

                        if_statinc(ifp, if_ierrors);
                        IGC_QUEUE_EVENT(q, rx_discard, 1);

                        DPRINTF(RX, "ierrors++\n");

                        goto next_desc;
                }

                if (__predict_false(mp == NULL)) {
                        panic("%s: igc_rxeof: NULL mbuf in slot %d "
                            "(filled %d)", device_xname(sc->sc_dev),
                            id, rxr->last_desc_filled);
                }

                if (!eop) {
                        /*
                         * Figure out the next descriptor of this frame.
                         */
                        int nextp = igc_rxdesc_incr(sc, id);

                        nxbuf = &rxr->rx_buffers[nextp];
                        /*
                         * TODO prefetch(nxbuf);
                         */
                }

                mp->m_len = len;

                m = rxbuf->fmp;
                rxbuf->fmp = NULL;

                if (m != NULL) {
                        m->m_pkthdr.len += mp->m_len;
                } else {
                        m = mp;
                        m->m_pkthdr.len = mp->m_len;
#if NVLAN > 0
                        if (staterr & IGC_RXD_STAT_VP)
                                vlan_set_tag(m, vtag);
#endif
                }

                /* Pass the head pointer on */
                if (!eop) {
                        nxbuf->fmp = m;
                        m = NULL;
                        mp->m_next = nxbuf->buf;
                } else {
                        m_set_rcvif(m, ifp);

                        m->m_pkthdr.csum_flags = igc_rx_checksum(q,
                            ifp->if_capenable, staterr, ptype);

#ifdef notyet
                        if (hashtype != IGC_RXDADV_RSSTYPE_NONE) {
                                m->m_pkthdr.ph_flowid = hash;
                                SET(m->m_pkthdr.csum_flags, M_FLOWID);
                        }
                        ml_enqueue(&ml, m);
#endif

                        if_percpuq_enqueue(sc->sc_ipq, m);

                        if_statinc(ifp, if_ipackets);
                        IGC_QUEUE_EVENT(q, rx_packets, 1);
                        IGC_QUEUE_EVENT(q, rx_bytes, m->m_pkthdr.len);
                }
 next_desc:
                /* Advance our pointers to the next descriptor. */
                id = igc_rxdesc_incr(sc, id);
        }

        DPRINTF(RX, "%s n2c %d id %d\n",
            rxr->next_to_check == id ? "same" : "diff",
            rxr->next_to_check, id);
        rxr->next_to_check = id;

        DPRINTF(RX, "fill queue[%d]\n", rxr->me);
        if (igc_rxrefill(rxr))
                callout_schedule(&rxr->rx_refill, 1);

#ifdef OPENBSD
        if (!(staterr & IGC_RXD_STAT_DD))
                return 0;
#endif

        return more;
}

/*********************************************************************
 *
 *  Verify that the hardware indicated that the checksum is valid.
 *  Inform the stack about the status of checksum so that stack
 *  doesn't spend time verifying the checksum.
 *
 *********************************************************************/
static int
igc_rx_checksum(struct igc_queue *q, uint64_t capenable, uint32_t staterr,
    uint32_t ptype)
{
        const uint16_t status = (uint16_t)staterr;
        const uint8_t errors = (uint8_t)(staterr >> 24);
        int flags = 0;

        if ((status & IGC_RXD_STAT_IPCS) != 0 &&
            (capenable & IFCAP_CSUM_IPv4_Rx) != 0) {
                IGC_DRIVER_EVENT(q, rx_ipcs, 1);
                flags |= M_CSUM_IPv4;
                if (__predict_false((errors & IGC_RXD_ERR_IPE) != 0)) {
                        IGC_DRIVER_EVENT(q, rx_ipcs_bad, 1);
                        flags |= M_CSUM_IPv4_BAD;
                }
        }

        if ((status & IGC_RXD_STAT_TCPCS) != 0) {
                IGC_DRIVER_EVENT(q, rx_tcpcs, 1);
                if ((capenable & IFCAP_CSUM_TCPv4_Rx) != 0)
                        flags |= M_CSUM_TCPv4;
                if ((capenable & IFCAP_CSUM_TCPv6_Rx) != 0)
                        flags |= M_CSUM_TCPv6;
        }

        if ((status & IGC_RXD_STAT_UDPCS) != 0) {
                IGC_DRIVER_EVENT(q, rx_udpcs, 1);
                if ((capenable & IFCAP_CSUM_UDPv4_Rx) != 0)
                        flags |= M_CSUM_UDPv4;
                if ((capenable & IFCAP_CSUM_UDPv6_Rx) != 0)
                        flags |= M_CSUM_UDPv6;
        }

        if (__predict_false((errors & IGC_RXD_ERR_TCPE) != 0)) {
                IGC_DRIVER_EVENT(q, rx_l4cs_bad, 1);
                if ((flags & ~M_CSUM_IPv4) != 0)
                        flags |= M_CSUM_TCP_UDP_BAD;
        }

        return flags;
}

static void
igc_watchdog(struct ifnet * ifp)
{
}

static void
igc_tick(void *arg)
{
        struct igc_softc *sc = arg;

        mutex_enter(&sc->sc_core_lock);

        if (__predict_false(sc->sc_core_stopping)) {
                mutex_exit(&sc->sc_core_lock);
                return;
        }

        /* XXX watchdog */
        if (0) {
                IGC_GLOBAL_EVENT(sc, watchdog, 1);
        }

        igc_update_counters(sc);

        mutex_exit(&sc->sc_core_lock);

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

/*********************************************************************
 *
 *  Media Ioctl callback
 *
 *  This routine is called whenever the user queries the status of
 *  the interface using ifconfig.
 *
 **********************************************************************/
static void
igc_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
{
        struct igc_softc *sc = ifp->if_softc;
        struct igc_hw *hw = &sc->hw;

        igc_update_link_status(sc);

        ifmr->ifm_status = IFM_AVALID;
        ifmr->ifm_active = IFM_ETHER;

        if (!sc->link_active) {
                ifmr->ifm_active |= IFM_NONE;
                return;
        }

        ifmr->ifm_status |= IFM_ACTIVE;

        switch (sc->link_speed) {
        case 10:
                ifmr->ifm_active |= IFM_10_T;
                break;
        case 100:
                ifmr->ifm_active |= IFM_100_TX;
                break;
        case 1000:
                ifmr->ifm_active |= IFM_1000_T;
                break;
        case 2500:
                ifmr->ifm_active |= IFM_2500_T;
                break;
        }

        if (sc->link_duplex == FULL_DUPLEX)
                ifmr->ifm_active |= IFM_FDX;
        else
                ifmr->ifm_active |= IFM_HDX;

        switch (hw->fc.current_mode) {
        case igc_fc_tx_pause:
                ifmr->ifm_active |= IFM_FLOW | IFM_ETH_TXPAUSE;
                break;
        case igc_fc_rx_pause:
                ifmr->ifm_active |= IFM_FLOW | IFM_ETH_RXPAUSE;
                break;
        case igc_fc_full:
                ifmr->ifm_active |= IFM_FLOW |
                    IFM_ETH_TXPAUSE | IFM_ETH_RXPAUSE;
                break;
        case igc_fc_none:
        default:
                break;
        }
}

/*********************************************************************
 *
 *  Media Ioctl callback
 *
 *  This routine is called when the user changes speed/duplex using
 *  media/mediopt option with ifconfig.
 *
 **********************************************************************/
static int
igc_media_change(struct ifnet *ifp)
{
        struct igc_softc *sc = ifp->if_softc;
        struct ifmedia *ifm = &sc->media;

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

        sc->hw.mac.autoneg = DO_AUTO_NEG;

        switch (IFM_SUBTYPE(ifm->ifm_media)) {
        case IFM_AUTO:
                sc->hw.phy.autoneg_advertised = AUTONEG_ADV_DEFAULT;
                break;
        case IFM_2500_T:
                sc->hw.phy.autoneg_advertised = ADVERTISE_2500_FULL;
                break;
        case IFM_1000_T:
                sc->hw.phy.autoneg_advertised = ADVERTISE_1000_FULL;
                break;
        case IFM_100_TX:
                if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
                        sc->hw.phy.autoneg_advertised = ADVERTISE_100_FULL;
                else
                        sc->hw.phy.autoneg_advertised = ADVERTISE_100_HALF;
                break;
        case IFM_10_T:
                if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
                        sc->hw.phy.autoneg_advertised = ADVERTISE_10_FULL;
                else
                        sc->hw.phy.autoneg_advertised = ADVERTISE_10_HALF;
                break;
        default:
                return EINVAL;
        }

        igc_init_locked(sc);

        return 0;
}

static int
igc_ifflags_cb(struct ethercom *ec)
{
        struct ifnet *ifp = &ec->ec_if;
        struct igc_softc *sc = ifp->if_softc;
        int rc = 0;
        u_short iffchange;
        bool needreset = false;

        DPRINTF(CFG, "called\n");

        KASSERT(IFNET_LOCKED(ifp));

        mutex_enter(&sc->sc_core_lock);

        /*
         * Check for if_flags.
         * Main usage is to prevent linkdown when opening bpf.
         */
        iffchange = ifp->if_flags ^ sc->sc_if_flags;
        sc->sc_if_flags = ifp->if_flags;
        if ((iffchange & ~(IFF_CANTCHANGE | IFF_DEBUG)) != 0) {
                needreset = true;
                goto ec;
        }

        /* iff related updates */
        if ((iffchange & IFF_PROMISC) != 0)
                igc_set_filter(sc);

#ifdef notyet
        igc_set_vlan(sc);
#endif

ec:
#ifdef notyet
        /* Check for ec_capenable. */
        ecchange = ec->ec_capenable ^ sc->sc_ec_capenable;
        sc->sc_ec_capenable = ec->ec_capenable;
        if ((ecchange & ~ETHERCAP_SOMETHING) != 0) {
                needreset = true;
                goto out;
        }
#endif
        if (needreset)
                rc = ENETRESET;

        mutex_exit(&sc->sc_core_lock);

        return rc;
}

static void
igc_set_filter(struct igc_softc *sc)
{
        struct ethercom *ec = &sc->sc_ec;
        uint32_t rctl;

        rctl = IGC_READ_REG(&sc->hw, IGC_RCTL);
        rctl &= ~(IGC_RCTL_BAM |IGC_RCTL_UPE | IGC_RCTL_MPE);

        if ((sc->sc_if_flags & IFF_BROADCAST) != 0)
                rctl |= IGC_RCTL_BAM;
        if ((sc->sc_if_flags & IFF_PROMISC) != 0) {
                DPRINTF(CFG, "promisc\n");
                rctl |= IGC_RCTL_UPE;
                ETHER_LOCK(ec);
 allmulti:
                ec->ec_flags |= ETHER_F_ALLMULTI;
                ETHER_UNLOCK(ec);
                rctl |= IGC_RCTL_MPE;
        } else {
                struct ether_multistep step;
                struct ether_multi *enm;
                int mcnt = 0;

                memset(sc->mta, 0, IGC_MTA_LEN);

                ETHER_LOCK(ec);
                ETHER_FIRST_MULTI(step, ec, enm);
                while (enm != NULL) {
                        if (((memcmp(enm->enm_addrlo, enm->enm_addrhi,
                                        ETHER_ADDR_LEN)) != 0) ||
                            (mcnt >= MAX_NUM_MULTICAST_ADDRESSES)) {
                                /*
                                 * We must listen to a range of multicast
                                 * addresses. For now, just accept all
                                 * multicasts, rather than trying to set only
                                 * those filter bits needed to match the range.
                                 * (At this time, the only use of address
                                 * ranges is for IP multicast routing, for
                                 * which the range is big enough to require all
                                 * bits set.)
                                 */
                                goto allmulti;
                        }
                        DPRINTF(CFG, "%d: %s\n", mcnt,
                            ether_sprintf(enm->enm_addrlo));
                        memcpy(&sc->mta[mcnt * ETHER_ADDR_LEN],
                            enm->enm_addrlo, ETHER_ADDR_LEN);

                        mcnt++;
                        ETHER_NEXT_MULTI(step, enm);
                }
                ec->ec_flags &= ~ETHER_F_ALLMULTI;
                ETHER_UNLOCK(ec);

                DPRINTF(CFG, "hw filter\n");
                igc_update_mc_addr_list(&sc->hw, sc->mta, mcnt);
        }

        IGC_WRITE_REG(&sc->hw, IGC_RCTL, rctl);
}

static void
igc_update_link_status(struct igc_softc *sc)
{
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        struct igc_hw *hw = &sc->hw;

        if (hw->mac.get_link_status == true)
                igc_check_for_link(hw);

        if (IGC_READ_REG(&sc->hw, IGC_STATUS) & IGC_STATUS_LU) {
                if (sc->link_active == 0) {
                        igc_get_speed_and_duplex(hw, &sc->link_speed,
                            &sc->link_duplex);
                        sc->link_active = 1;
                        ifp->if_baudrate = IF_Mbps(sc->link_speed);
                        if_link_state_change(ifp, LINK_STATE_UP);
                }
        } else {
                if (sc->link_active == 1) {
                        ifp->if_baudrate = sc->link_speed = 0;
                        sc->link_duplex = 0;
                        sc->link_active = 0;
                        if_link_state_change(ifp, LINK_STATE_DOWN);
                }
        }
}

/*********************************************************************
 *
 *  Get a buffer from system mbuf buffer pool.
 *
 **********************************************************************/
static int
igc_get_buf(struct rx_ring *rxr, int id, bool strict)
{
        struct igc_softc *sc = rxr->sc;
        struct igc_queue *q = rxr->rxr_igcq;
        struct igc_rx_buf *rxbuf = &rxr->rx_buffers[id];
        bus_dmamap_t map = rxbuf->map;
        struct mbuf *m;
        int error;

        if (__predict_false(rxbuf->buf)) {
                if (strict) {
                        DPRINTF(RX, "slot %d already has an mbuf\n", id);
                        return EINVAL;
                }
                return 0;
        }

        MGETHDR(m, M_DONTWAIT, MT_DATA);
        if (__predict_false(m == NULL)) {
 enobuf:
                IGC_QUEUE_EVENT(q, rx_no_mbuf, 1);
                return ENOBUFS;
        }
        MCLAIM(m, &sc->sc_ec.ec_rx_mowner);

        MCLGET(m, M_DONTWAIT);
        if (__predict_false(!(m->m_flags & M_EXT))) {
                m_freem(m);
                goto enobuf;
        }

        m->m_len = m->m_pkthdr.len = sc->rx_mbuf_sz;

        error = bus_dmamap_load_mbuf(rxr->rxdma.dma_tag, map, m,
            BUS_DMA_READ | BUS_DMA_NOWAIT);
        if (error) {
                m_freem(m);
                return error;
        }

        bus_dmamap_sync(rxr->rxdma.dma_tag, map, 0,
            map->dm_mapsize, BUS_DMASYNC_PREREAD);
        rxbuf->buf = m;

        union igc_adv_rx_desc *rxdesc = &rxr->rx_base[id];
        igc_rxdesc_sync(rxr, id, BUS_DMASYNC_POSTWRITE | BUS_DMASYNC_POSTREAD);
        rxdesc->read.pkt_addr = htole64(map->dm_segs[0].ds_addr);
        igc_rxdesc_sync(rxr, id, BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);

        return 0;
}

static void
igc_configure_queues(struct igc_softc *sc)
{
        struct igc_hw *hw = &sc->hw;
        uint32_t ivar;

        /* First turn on RSS capability */
        IGC_WRITE_REG(hw, IGC_GPIE, IGC_GPIE_MSIX_MODE | IGC_GPIE_EIAME |
            IGC_GPIE_PBA | IGC_GPIE_NSICR);

        /* Set the starting interrupt rate */
        uint32_t newitr = (4000000 / MAX_INTS_PER_SEC) & 0x7FFC;
        newitr |= IGC_EITR_CNT_IGNR;

        /* Turn on MSI-X */
        uint32_t newmask = 0;
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct igc_queue *q = &sc->queues[iq];

                /* RX entries */
                igc_set_queues(sc, iq, q->msix, 0);
                /* TX entries */
                igc_set_queues(sc, iq, q->msix, 1);
                newmask |= q->eims;
                IGC_WRITE_REG(hw, IGC_EITR(q->msix), newitr);
        }
        sc->msix_queuesmask = newmask;

#if 1
        ivar = IGC_READ_REG_ARRAY(hw, IGC_IVAR0, 0);
        DPRINTF(CFG, "ivar(0)=0x%x\n", ivar);
        ivar = IGC_READ_REG_ARRAY(hw, IGC_IVAR0, 1);
        DPRINTF(CFG, "ivar(1)=0x%x\n", ivar);
#endif

        /* And for the link interrupt */
        ivar = (sc->linkvec | IGC_IVAR_VALID) << 8;
        sc->msix_linkmask = 1 << sc->linkvec;
        IGC_WRITE_REG(hw, IGC_IVAR_MISC, ivar);
}

static void
igc_set_queues(struct igc_softc *sc, uint32_t entry, uint32_t vector, int type)
{
        struct igc_hw *hw = &sc->hw;
        const uint32_t index = entry >> 1;
        uint32_t ivar = IGC_READ_REG_ARRAY(hw, IGC_IVAR0, index);

        if (type) {
                if (entry & 1) {
                        ivar &= 0x00FFFFFF;
                        ivar |= (vector | IGC_IVAR_VALID) << 24;
                } else {
                        ivar &= 0xFFFF00FF;
                        ivar |= (vector | IGC_IVAR_VALID) << 8;
                }
        } else {
                if (entry & 1) {
                        ivar &= 0xFF00FFFF;
                        ivar |= (vector | IGC_IVAR_VALID) << 16;
                } else {
                        ivar &= 0xFFFFFF00;
                        ivar |= vector | IGC_IVAR_VALID;
                }
        }
        IGC_WRITE_REG_ARRAY(hw, IGC_IVAR0, index, ivar);
}

static void
igc_enable_queue(struct igc_softc *sc, uint32_t eims)
{
        IGC_WRITE_REG(&sc->hw, IGC_EIMS, eims);
}

static void
igc_enable_intr(struct igc_softc *sc)
{
        struct igc_hw *hw = &sc->hw;

        if (sc->sc_intr_type == PCI_INTR_TYPE_MSIX) {
                const uint32_t mask = sc->msix_queuesmask | sc->msix_linkmask;

                IGC_WRITE_REG(hw, IGC_EIAC, mask);
                IGC_WRITE_REG(hw, IGC_EIAM, mask);
                IGC_WRITE_REG(hw, IGC_EIMS, mask);
                IGC_WRITE_REG(hw, IGC_IMS, IGC_IMS_LSC);
        } else {
                IGC_WRITE_REG(hw, IGC_IMS, IMS_ENABLE_MASK);
        }
        IGC_WRITE_FLUSH(hw);
}

static void
igc_disable_intr(struct igc_softc *sc)
{
        struct igc_hw *hw = &sc->hw;

        if (sc->sc_intr_type == PCI_INTR_TYPE_MSIX) {
                IGC_WRITE_REG(hw, IGC_EIMC, 0xffffffff);
                IGC_WRITE_REG(hw, IGC_EIAC, 0);
        }
        IGC_WRITE_REG(hw, IGC_IMC, 0xffffffff);
        IGC_WRITE_FLUSH(hw);
}

static int
igc_intr_link(void *arg)
{
        struct igc_softc *sc = (struct igc_softc *)arg;
        const uint32_t reg_icr = IGC_READ_REG(&sc->hw, IGC_ICR);

        IGC_GLOBAL_EVENT(sc, link, 1);

        if (reg_icr & IGC_ICR_LSC) {
                mutex_enter(&sc->sc_core_lock);
                sc->hw.mac.get_link_status = true;
                igc_update_link_status(sc);
                mutex_exit(&sc->sc_core_lock);
        }

        IGC_WRITE_REG(&sc->hw, IGC_IMS, IGC_IMS_LSC);
        IGC_WRITE_REG(&sc->hw, IGC_EIMS, sc->msix_linkmask);

        return 1;
}

static int
igc_intr_queue(void *arg)
{
        struct igc_queue *iq = arg;
        struct igc_softc *sc = iq->sc;
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        struct rx_ring *rxr = iq->rxr;
        struct tx_ring *txr = iq->txr;
        const u_int txlimit = sc->sc_tx_intr_process_limit,
                    rxlimit = sc->sc_rx_intr_process_limit;
        bool txmore, rxmore;

        IGC_QUEUE_EVENT(iq, irqs, 1);

        if (__predict_false(!ISSET(ifp->if_flags, IFF_RUNNING)))
                return 0;

        mutex_enter(&txr->txr_lock);
        txmore = igc_txeof(txr, txlimit);
        mutex_exit(&txr->txr_lock);
        mutex_enter(&rxr->rxr_lock);
        rxmore = igc_rxeof(rxr, rxlimit);
        mutex_exit(&rxr->rxr_lock);

        if (txmore || rxmore) {
                IGC_QUEUE_EVENT(iq, req, 1);
                igc_sched_handle_queue(sc, iq);
        } else {
                igc_enable_queue(sc, iq->eims);
        }

        return 1;
}

static int
igc_intr(void *arg)
{
        struct igc_softc *sc = arg;
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        struct igc_queue *iq = &sc->queues[0];
        struct rx_ring *rxr = iq->rxr;
        struct tx_ring *txr = iq->txr;
        const u_int txlimit = sc->sc_tx_intr_process_limit,
                    rxlimit = sc->sc_rx_intr_process_limit;
        bool txmore, rxmore;

        if (__predict_false(!ISSET(ifp->if_flags, IFF_RUNNING)))
                return 0;

        const uint32_t reg_icr = IGC_READ_REG(&sc->hw, IGC_ICR);
        DPRINTF(MISC, "reg_icr=0x%x\n", reg_icr);

        /* Definitely not our interrupt. */
        if (reg_icr == 0x0) {
                DPRINTF(MISC, "not for me\n");
                return 0;
        }

        IGC_QUEUE_EVENT(iq, irqs, 1);

        /* Hot eject? */
        if (__predict_false(reg_icr == 0xffffffff)) {
                DPRINTF(MISC, "hot eject\n");
                return 0;
        }

        if (__predict_false(!(reg_icr & IGC_ICR_INT_ASSERTED))) {
                DPRINTF(MISC, "not set IGC_ICR_INT_ASSERTED");
                return 0;
        }

        /*
         * Only MSI-X interrupts have one-shot behavior by taking advantage
         * of the EIAC register.  Thus, explicitly disable interrupts.  This
         * also works around the MSI message reordering errata on certain
         * systems.
         */
        igc_disable_intr(sc);

        mutex_enter(&txr->txr_lock);
        txmore = igc_txeof(txr, txlimit);
        mutex_exit(&txr->txr_lock);
        mutex_enter(&rxr->rxr_lock);
        rxmore = igc_rxeof(rxr, rxlimit);
        mutex_exit(&rxr->rxr_lock);

        /* Link status change */
        // XXXX FreeBSD checks IGC_ICR_RXSEQ
        if (__predict_false(reg_icr & IGC_ICR_LSC)) {
                IGC_GLOBAL_EVENT(sc, link, 1);
                mutex_enter(&sc->sc_core_lock);
                sc->hw.mac.get_link_status = true;
                igc_update_link_status(sc);
                mutex_exit(&sc->sc_core_lock);
        }

        if (txmore || rxmore) {
                IGC_QUEUE_EVENT(iq, req, 1);
                igc_sched_handle_queue(sc, iq);
        } else {
                igc_enable_intr(sc);
        }

        return 1;
}

static void
igc_handle_queue(void *arg)
{
        struct igc_queue *iq = arg;
        struct igc_softc *sc = iq->sc;
        struct tx_ring *txr = iq->txr;
        struct rx_ring *rxr = iq->rxr;
        const u_int txlimit = sc->sc_tx_process_limit,
                    rxlimit = sc->sc_rx_process_limit;
        bool txmore, rxmore;

        IGC_QUEUE_EVENT(iq, handleq, 1);

        mutex_enter(&txr->txr_lock);
        txmore = igc_txeof(txr, txlimit);
        /* for ALTQ, dequeue from if_snd */
        if (txr->me == 0) {
                struct ifnet *ifp = &sc->sc_ec.ec_if;

                igc_tx_common_locked(ifp, txr, IGC_TX_START);
        }
        mutex_exit(&txr->txr_lock);

        mutex_enter(&rxr->rxr_lock);
        rxmore = igc_rxeof(rxr, rxlimit);
        mutex_exit(&rxr->rxr_lock);

        if (txmore || rxmore) {
                igc_sched_handle_queue(sc, iq);
        } else {
                if (sc->sc_intr_type == PCI_INTR_TYPE_MSIX)
                        igc_enable_queue(sc, iq->eims);
                else
                        igc_enable_intr(sc);
        }
}

static void
igc_handle_queue_work(struct work *wk, void *context)
{
        struct igc_queue *iq =
            container_of(wk, struct igc_queue, igcq_wq_cookie);

        igc_handle_queue(iq);
}

static void
igc_sched_handle_queue(struct igc_softc *sc, struct igc_queue *iq)
{

        if (iq->igcq_workqueue) {
                /* XXXRO notyet */
                workqueue_enqueue(sc->sc_queue_wq, &iq->igcq_wq_cookie,
                    curcpu());
        } else {
                softint_schedule(iq->igcq_si);
        }
}

static void
igc_barrier_handle_queue(struct igc_softc *sc)
{

        if (sc->sc_txrx_workqueue) {
                for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                        struct igc_queue *q = &sc->queues[iq];

                        workqueue_wait(sc->sc_queue_wq, &q->igcq_wq_cookie);
                }
        } else {
                xc_barrier(0);
        }
}

/*********************************************************************
 *
 *  Allocate memory for tx_buffer structures. The tx_buffer stores all
 *  the information needed to transmit a packet on the wire.
 *
 **********************************************************************/
static int
igc_allocate_transmit_buffers(struct tx_ring *txr)
{
        struct igc_softc *sc = txr->sc;
        int error;

        txr->tx_buffers =
            kmem_zalloc(sc->num_tx_desc * sizeof(struct igc_tx_buf), KM_SLEEP);
        txr->txtag = txr->txdma.dma_tag;

        /* Create the descriptor buffer dma maps. */
        for (int id = 0; id < sc->num_tx_desc; id++) {
                struct igc_tx_buf *txbuf = &txr->tx_buffers[id];

                error = bus_dmamap_create(txr->txdma.dma_tag,
                    round_page(IGC_TSO_SIZE + sizeof(struct ether_vlan_header)),
                    IGC_MAX_SCATTER, PAGE_SIZE, 0, BUS_DMA_NOWAIT, &txbuf->map);
                if (error != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "unable to create TX DMA map\n");
                        goto fail;
                }

                txbuf->eop_index = -1;
        }

        return 0;
 fail:
        return error;
}


/*********************************************************************
 *
 *  Allocate and initialize transmit structures.
 *
 **********************************************************************/
static int
igc_setup_transmit_structures(struct igc_softc *sc)
{

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct tx_ring *txr = &sc->tx_rings[iq];

                if (igc_setup_transmit_ring(txr))
                        goto fail;
        }

        return 0;
 fail:
        igc_free_transmit_structures(sc);
        return ENOBUFS;
}

/*********************************************************************
 *
 *  Initialize a transmit ring.
 *
 **********************************************************************/
static int
igc_setup_transmit_ring(struct tx_ring *txr)
{
        struct igc_softc *sc = txr->sc;

        /* Now allocate transmit buffers for the ring. */
        if (igc_allocate_transmit_buffers(txr))
                return ENOMEM;

        /* Clear the old ring contents */
        memset(txr->tx_base, 0,
            sizeof(union igc_adv_tx_desc) * sc->num_tx_desc);

        /* Reset indices. */
        txr->next_avail_desc = 0;
        txr->next_to_clean = 0;

        bus_dmamap_sync(txr->txdma.dma_tag, txr->txdma.dma_map, 0,
            txr->txdma.dma_map->dm_mapsize,
            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

        txr->txr_interq = pcq_create(sc->num_tx_desc, KM_SLEEP);

        mutex_init(&txr->txr_lock, MUTEX_DEFAULT, IPL_NET);

        return 0;
}

/*********************************************************************
 *
 *  Enable transmit unit.
 *
 **********************************************************************/
static void
igc_initialize_transmit_unit(struct igc_softc *sc)
{
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        struct igc_hw *hw = &sc->hw;

        /* Setup the Base and Length of the TX descriptor ring. */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct tx_ring *txr = &sc->tx_rings[iq];
                const uint64_t bus_addr =
                    txr->txdma.dma_map->dm_segs[0].ds_addr;

                /* Base and len of TX ring */
                IGC_WRITE_REG(hw, IGC_TDLEN(iq),
                    sc->num_tx_desc * sizeof(union igc_adv_tx_desc));
                IGC_WRITE_REG(hw, IGC_TDBAH(iq), (uint32_t)(bus_addr >> 32));
                IGC_WRITE_REG(hw, IGC_TDBAL(iq), (uint32_t)bus_addr);

                /* Init the HEAD/TAIL indices */
                IGC_WRITE_REG(hw, IGC_TDT(iq), 0 /* XXX txr->next_avail_desc */);
                IGC_WRITE_REG(hw, IGC_TDH(iq), 0);

                txr->watchdog_timer = 0;

                uint32_t txdctl = 0;    /* Clear txdctl */
                txdctl |= 0x1f;         /* PTHRESH */
                txdctl |= 1 << 8;       /* HTHRESH */
                txdctl |= 1 << 16;      /* WTHRESH */
                txdctl |= 1 << 22;      /* Reserved bit 22 must always be 1 */
                txdctl |= IGC_TXDCTL_GRAN;
                txdctl |= 1 << 25;      /* LWTHRESH */

                IGC_WRITE_REG(hw, IGC_TXDCTL(iq), txdctl);
        }
        ifp->if_timer = 0;

        /* Program the Transmit Control Register */
        uint32_t tctl = IGC_READ_REG(&sc->hw, IGC_TCTL);
        tctl &= ~IGC_TCTL_CT;
        tctl |= (IGC_TCTL_PSP | IGC_TCTL_RTLC | IGC_TCTL_EN |
            (IGC_COLLISION_THRESHOLD << IGC_CT_SHIFT));

        /* This write will effectively turn on the transmit unit. */
        IGC_WRITE_REG(&sc->hw, IGC_TCTL, tctl);
}

/*********************************************************************
 *
 *  Free all transmit rings.
 *
 **********************************************************************/
static void
igc_free_transmit_structures(struct igc_softc *sc)
{

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct tx_ring *txr = &sc->tx_rings[iq];

                igc_free_transmit_buffers(txr);
        }
}

/*********************************************************************
 *
 *  Free transmit ring related data structures.
 *
 **********************************************************************/
static void
igc_free_transmit_buffers(struct tx_ring *txr)
{
        struct igc_softc *sc = txr->sc;

        if (txr->tx_buffers == NULL)
                return;

        igc_withdraw_transmit_packets(txr, true);

        kmem_free(txr->tx_buffers,
            sc->num_tx_desc * sizeof(struct igc_tx_buf));
        txr->tx_buffers = NULL;
        txr->txtag = NULL;

        pcq_destroy(txr->txr_interq);
        mutex_destroy(&txr->txr_lock);
}

/*********************************************************************
 *
 *  Withdraw transmit packets.
 *
 **********************************************************************/
static void
igc_withdraw_transmit_packets(struct tx_ring *txr, bool destroy)
{
        struct igc_softc *sc = txr->sc;
        struct igc_queue *q = txr->txr_igcq;

        mutex_enter(&txr->txr_lock);

        for (int id = 0; id < sc->num_tx_desc; id++) {
                union igc_adv_tx_desc *txdesc = &txr->tx_base[id];

                igc_txdesc_sync(txr, id,
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                txdesc->read.buffer_addr = 0;
                txdesc->read.cmd_type_len = 0;
                txdesc->read.olinfo_status = 0;
                igc_txdesc_sync(txr, id,
                    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

                struct igc_tx_buf *txbuf = &txr->tx_buffers[id];
                bus_dmamap_t map = txbuf->map;

                if (map != NULL && map->dm_nsegs > 0) {
                        bus_dmamap_sync(txr->txdma.dma_tag, map,
                            0, map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
                        bus_dmamap_unload(txr->txdma.dma_tag, map);
                }
                m_freem(txbuf->m_head);
                txbuf->m_head = NULL;
                if (map != NULL && destroy) {
                        bus_dmamap_destroy(txr->txdma.dma_tag, map);
                        txbuf->map = NULL;
                }
                txbuf->eop_index = -1;

                txr->next_avail_desc = 0;
                txr->next_to_clean = 0;
        }

        struct mbuf *m;
        while ((m = pcq_get(txr->txr_interq)) != NULL) {
                IGC_QUEUE_EVENT(q, tx_pcq_drop, 1);
                m_freem(m);
        }

        mutex_exit(&txr->txr_lock);
}


/*********************************************************************
 *
 *  Advanced Context Descriptor setup for VLAN, CSUM or TSO
 *
 **********************************************************************/

static bool
igc_tx_ctx_setup(struct tx_ring *txr, struct mbuf *mp, int prod,
    uint32_t *cmd_type_len, uint32_t *olinfo_status)
{
        struct ether_vlan_header *evl;
        struct tcphdr *th = NULL /* XXXGCC */;
        uint32_t vlan_macip_lens = 0;
        uint32_t type_tucmd_mlhl = 0;
        uint32_t mss_l4len_idx = 0;
        uint32_t ehlen, iphlen;
        uint16_t ehtype;

        const int csum_flags = mp->m_pkthdr.csum_flags;
        const bool v4 = (csum_flags &
            (M_CSUM_IPv4 | M_CSUM_TCPv4 | M_CSUM_UDPv4 | M_CSUM_TSOv4)) != 0;
        const bool v6 = (csum_flags &
            (M_CSUM_UDPv6 | M_CSUM_TCPv6 | M_CSUM_TSOv6)) != 0;
        const bool tso = (csum_flags & (M_CSUM_TSOv4 | M_CSUM_TSOv6)) != 0;
        const bool tcp = tso ||
            (csum_flags & (M_CSUM_TCPv4 | M_CSUM_TCPv6)) != 0;
        const bool udp = (csum_flags & (M_CSUM_UDPv4 | M_CSUM_UDPv6)) != 0;

        /* Indicate the whole packet as payload when not doing TSO */
        if (!tso) {
                *olinfo_status |= mp->m_pkthdr.len << IGC_ADVTXD_PAYLEN_SHIFT;
        } else {
                /* Set L4 payload length later... */
        }

#if NVLAN > 0
        /*
         * In advanced descriptors the vlan tag must
         * be placed into the context descriptor. Hence
         * we need to make one even if not doing offloads.
         */
        if (vlan_has_tag(mp)) {
                vlan_macip_lens |= (uint32_t)vlan_get_tag(mp)
                    << IGC_ADVTXD_VLAN_SHIFT;
        } else
#endif
        if (!v4 && !v6)
                return false;

        KASSERT(mp->m_len >= sizeof(struct ether_header));
        evl = mtod(mp, struct ether_vlan_header *);
        if (evl->evl_encap_proto == htons(ETHERTYPE_VLAN)) {
                KASSERT(mp->m_len >= sizeof(struct ether_vlan_header));
                ehlen = ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN;
                ehtype = evl->evl_proto;
        } else {
                ehlen = ETHER_HDR_LEN;
                ehtype = evl->evl_encap_proto;
        }

        switch (ntohs(ehtype)) {
        case ETHERTYPE_IP:
                iphlen = M_CSUM_DATA_IPv4_IPHL(mp->m_pkthdr.csum_data);
                type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV4;

                if ((csum_flags & (M_CSUM_IPv4 | M_CSUM_TSOv4)) != 0)
                        *olinfo_status |= IGC_TXD_POPTS_IXSM << 8;

                if (!tso)
                        break;

                struct ip *ip;
                KASSERT(mp->m_len >= ehlen + sizeof(*ip));
                ip = (void *)(mtod(mp, char *) + ehlen);
                ip->ip_len = 0;

                KASSERT(mp->m_len >= ehlen + iphlen + sizeof(*th));
                th = (void *)((char *)ip + iphlen);
                th->th_sum = in_cksum_phdr(ip->ip_src.s_addr,
                    ip->ip_dst.s_addr, htons(IPPROTO_TCP));
                break;
        case ETHERTYPE_IPV6:
                iphlen = M_CSUM_DATA_IPv6_IPHL(mp->m_pkthdr.csum_data);
                type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV6;

                if (!tso)
                        break;

                struct ip6_hdr *ip6;
                KASSERT(mp->m_len >= ehlen + sizeof(*ip6));
                ip6 = (void *)(mtod(mp, char *) + ehlen);
                ip6->ip6_plen = 0;

                KASSERT(mp->m_len >= ehlen + iphlen + sizeof(*th));
                th = (void *)((char *)ip6 + iphlen);
                th->th_sum = in6_cksum_phdr(&ip6->ip6_src, &ip6->ip6_dst, 0,
                    htonl(IPPROTO_TCP));
                break;
        default:
                /*
                 * Unknown L3 protocol. Clear L3 header length and proceed for
                 * LAN as done by Linux driver.
                 */
                KASSERT(!v4 && !v6);
                iphlen = 0;
                break;
        }

        if (tcp) {
                type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_TCP;
                *olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
        } else if (udp) {
                type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_UDP;
                *olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
        }

        if (tso) {
                const uint32_t tcphlen = th->th_off << 2;
                const uint32_t paylen =
                    mp->m_pkthdr.len - ehlen - iphlen - tcphlen;

                mss_l4len_idx |= mp->m_pkthdr.segsz << IGC_ADVTXD_MSS_SHIFT;
                mss_l4len_idx |= tcphlen << IGC_ADVTXD_L4LEN_SHIFT;

                *cmd_type_len |= IGC_ADVTXD_DCMD_TSE;

                *olinfo_status |= paylen << IGC_ADVTXD_PAYLEN_SHIFT;
        }

        vlan_macip_lens |= iphlen;
        vlan_macip_lens |= ehlen << IGC_ADVTXD_MACLEN_SHIFT;

        type_tucmd_mlhl |= IGC_ADVTXD_DCMD_DEXT | IGC_ADVTXD_DTYP_CTXT;

        /* Now ready a context descriptor */
        struct igc_adv_tx_context_desc *txdesc =
            (struct igc_adv_tx_context_desc *)&txr->tx_base[prod];

        igc_txdesc_sync(txr, prod,
            BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);

        /* Now copy bits into descriptor */
        htolem32(&txdesc->vlan_macip_lens, vlan_macip_lens);
        htolem32(&txdesc->type_tucmd_mlhl, type_tucmd_mlhl);
        htolem32(&txdesc->seqnum_seed, 0);
        htolem32(&txdesc->mss_l4len_idx, mss_l4len_idx);

        igc_txdesc_sync(txr, prod,
            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

        return 1;
}

/*********************************************************************
 *
 *  Allocate memory for rx_buffer structures. Since we use one
 *  rx_buffer per received packet, the maximum number of rx_buffer's
 *  that we'll need is equal to the number of receive descriptors
 *  that we've allocated.
 *
 **********************************************************************/
static int
igc_allocate_receive_buffers(struct rx_ring *rxr)
{
        struct igc_softc *sc = rxr->sc;
        int error;

        rxr->rx_buffers =
            kmem_zalloc(sc->num_rx_desc * sizeof(struct igc_rx_buf), KM_SLEEP);

        for (int id = 0; id < sc->num_rx_desc; id++) {
                struct igc_rx_buf *rxbuf = &rxr->rx_buffers[id];

                error = bus_dmamap_create(rxr->rxdma.dma_tag, MCLBYTES, 1,
                    MCLBYTES, 0, BUS_DMA_WAITOK, &rxbuf->map);
                if (error) {
                        aprint_error_dev(sc->sc_dev,
                            "unable to create RX DMA map\n");
                        goto fail;
                }
        }
        bus_dmamap_sync(rxr->rxdma.dma_tag, rxr->rxdma.dma_map, 0,
            rxr->rxdma.dma_map->dm_mapsize,
            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

        return 0;
 fail:
        return error;
}

/*********************************************************************
 *
 *  Allocate and initialize receive structures.
 *
 **********************************************************************/
static int
igc_setup_receive_structures(struct igc_softc *sc)
{

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];

                if (igc_setup_receive_ring(rxr))
                        goto fail;
        }

        return 0;
 fail:
        igc_free_receive_structures(sc);
        return ENOBUFS;
}

/*********************************************************************
 *
 *  Initialize a receive ring and its buffers.
 *
 **********************************************************************/
static int
igc_setup_receive_ring(struct rx_ring *rxr)
{
        struct igc_softc *sc = rxr->sc;
        const int rsize = roundup2(
            sc->num_rx_desc * sizeof(union igc_adv_rx_desc), IGC_DBA_ALIGN);

        /* Clear the ring contents. */
        memset(rxr->rx_base, 0, rsize);

        if (igc_allocate_receive_buffers(rxr))
                return ENOMEM;

        /* Setup our descriptor indices. */
        rxr->next_to_check = 0;
        rxr->last_desc_filled = 0;

        mutex_init(&rxr->rxr_lock, MUTEX_DEFAULT, IPL_NET);

        return 0;
}

/*********************************************************************
 *
 *  Enable receive unit.
 *
 **********************************************************************/
static void
igc_initialize_receive_unit(struct igc_softc *sc)
{
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        struct igc_hw *hw = &sc->hw;
        uint32_t rctl, rxcsum, srrctl;

        DPRINTF(RX, "called\n");

        /*
         * Make sure receives are disabled while setting
         * up the descriptor ring.
         */
        rctl = IGC_READ_REG(hw, IGC_RCTL);
        IGC_WRITE_REG(hw, IGC_RCTL, rctl & ~IGC_RCTL_EN);

        /* Setup the Receive Control Register */
        rctl &= ~(3 << IGC_RCTL_MO_SHIFT);
        rctl |= IGC_RCTL_EN | IGC_RCTL_BAM | IGC_RCTL_LBM_NO |
            IGC_RCTL_RDMTS_HALF | (hw->mac.mc_filter_type << IGC_RCTL_MO_SHIFT);

#if 1
        /* Do not store bad packets */
        rctl &= ~IGC_RCTL_SBP;
#else
        /* for debug */
        rctl |= IGC_RCTL_SBP;
#endif

        /* Enable Long Packet receive */
        if (sc->hw.mac.max_frame_size > ETHER_MAX_LEN)
                rctl |= IGC_RCTL_LPE;
        else
                rctl &= ~IGC_RCTL_LPE;

        /* Strip the CRC */
        rctl |= IGC_RCTL_SECRC;

        /*
         * Set the interrupt throttling rate. Value is calculated
         * as DEFAULT_ITR = 1/(MAX_INTS_PER_SEC * 256ns)
         *
         * XXX Sync with Linux, especially for jumbo MTU or TSO.
         * XXX Shouldn't be here?
         */
        IGC_WRITE_REG(hw, IGC_ITR, DEFAULT_ITR);

        rxcsum = IGC_READ_REG(hw, IGC_RXCSUM);
        rxcsum &= ~(IGC_RXCSUM_IPOFL | IGC_RXCSUM_TUOFL | IGC_RXCSUM_PCSD);
        if (ifp->if_capenable & IFCAP_CSUM_IPv4_Rx)
                rxcsum |= IGC_RXCSUM_IPOFL;
        if (ifp->if_capenable & (IFCAP_CSUM_TCPv4_Rx | IFCAP_CSUM_UDPv4_Rx |
                                 IFCAP_CSUM_TCPv6_Rx | IFCAP_CSUM_UDPv6_Rx))
                rxcsum |= IGC_RXCSUM_TUOFL;
        if (sc->sc_nqueues > 1)
                rxcsum |= IGC_RXCSUM_PCSD;
        IGC_WRITE_REG(hw, IGC_RXCSUM, rxcsum);

        if (sc->sc_nqueues > 1)
                igc_initialize_rss_mapping(sc);

        srrctl = 0;
#if 0
        srrctl |= 4096 >> IGC_SRRCTL_BSIZEPKT_SHIFT;
        rctl |= IGC_RCTL_SZ_4096 | IGC_RCTL_BSEX;
#else
        srrctl |= 2048 >> IGC_SRRCTL_BSIZEPKT_SHIFT;
        rctl |= IGC_RCTL_SZ_2048;
#endif

        /*
         * If TX flow control is disabled and there's > 1 queue defined,
         * enable DROP.
         *
         * This drops frames rather than hanging the RX MAC for all queues.
         */
        if (sc->sc_nqueues > 1 &&
            (sc->fc == igc_fc_none || sc->fc == igc_fc_rx_pause))
                srrctl |= IGC_SRRCTL_DROP_EN;

        /* Setup the Base and Length of the RX descriptor rings. */
        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];
                const uint64_t bus_addr =
                    rxr->rxdma.dma_map->dm_segs[0].ds_addr;

                IGC_WRITE_REG(hw, IGC_RXDCTL(iq), 0);

                srrctl |= IGC_SRRCTL_DESCTYPE_ADV_ONEBUF;

                IGC_WRITE_REG(hw, IGC_RDLEN(iq),
                    sc->num_rx_desc * sizeof(union igc_adv_rx_desc));
                IGC_WRITE_REG(hw, IGC_RDBAH(iq), (uint32_t)(bus_addr >> 32));
                IGC_WRITE_REG(hw, IGC_RDBAL(iq), (uint32_t)bus_addr);
                IGC_WRITE_REG(hw, IGC_SRRCTL(iq), srrctl);

                /* Setup the Head and Tail Descriptor Pointers */
                IGC_WRITE_REG(hw, IGC_RDH(iq), 0);
                IGC_WRITE_REG(hw, IGC_RDT(iq), 0 /* XXX rxr->last_desc_filled */);

                /* Enable this Queue */
                uint32_t rxdctl = IGC_READ_REG(hw, IGC_RXDCTL(iq));
                rxdctl |= IGC_RXDCTL_QUEUE_ENABLE;
                rxdctl &= 0xFFF00000;
                rxdctl |= IGC_RX_PTHRESH;
                rxdctl |= IGC_RX_HTHRESH << 8;
                rxdctl |= IGC_RX_WTHRESH << 16;
                IGC_WRITE_REG(hw, IGC_RXDCTL(iq), rxdctl);
        }

        /* Make sure VLAN Filters are off */
        rctl &= ~IGC_RCTL_VFE;

        /* Write out the settings */
        IGC_WRITE_REG(hw, IGC_RCTL, rctl);
}

/*********************************************************************
 *
 *  Free all receive rings.
 *
 **********************************************************************/
static void
igc_free_receive_structures(struct igc_softc *sc)
{

        for (int iq = 0; iq < sc->sc_nqueues; iq++) {
                struct rx_ring *rxr = &sc->rx_rings[iq];

                igc_free_receive_buffers(rxr);
        }
}

/*********************************************************************
 *
 *  Free receive ring data structures
 *
 **********************************************************************/
static void
igc_free_receive_buffers(struct rx_ring *rxr)
{
        struct igc_softc *sc = rxr->sc;

        callout_halt(&rxr->rx_refill, &rxr->rxr_lock);
        callout_destroy(&rxr->rx_refill);

        if (rxr->rx_buffers != NULL) {
                for (int id = 0; id < sc->num_rx_desc; id++) {
                        struct igc_rx_buf *rxbuf = &rxr->rx_buffers[id];
                        bus_dmamap_t map = rxbuf->map;

                        if (rxbuf->buf != NULL) {
                                bus_dmamap_sync(rxr->rxdma.dma_tag, map,
                                    0, map->dm_mapsize, BUS_DMASYNC_POSTREAD);
                                bus_dmamap_unload(rxr->rxdma.dma_tag, map);
                                m_freem(rxbuf->buf);
                                rxbuf->buf = NULL;
                        }
                        bus_dmamap_destroy(rxr->rxdma.dma_tag, map);
                        rxbuf->map = NULL;
                }
                kmem_free(rxr->rx_buffers,
                    sc->num_rx_desc * sizeof(struct igc_rx_buf));
                rxr->rx_buffers = NULL;
        }

        mutex_destroy(&rxr->rxr_lock);
}

/*********************************************************************
 *
 * Clear status registers in all RX descriptors.
 *
 **********************************************************************/
static void
igc_clear_receive_status(struct rx_ring *rxr)
{
        struct igc_softc *sc = rxr->sc;

        mutex_enter(&rxr->rxr_lock);

        for (int id = 0; id < sc->num_rx_desc; id++) {
                union igc_adv_rx_desc *rxdesc = &rxr->rx_base[id];

                igc_rxdesc_sync(rxr, id,
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                rxdesc->wb.upper.status_error = 0;
                igc_rxdesc_sync(rxr, id,
                    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
        }

        mutex_exit(&rxr->rxr_lock);
}

/*
 * Initialise the RSS mapping for NICs that support multiple transmit/
 * receive rings.
 */
static void
igc_initialize_rss_mapping(struct igc_softc *sc)
{
        struct igc_hw *hw = &sc->hw;

        /*
         * The redirection table controls which destination
         * queue each bucket redirects traffic to.
         * Each DWORD represents four queues, with the LSB
         * being the first queue in the DWORD.
         *
         * This just allocates buckets to queues using round-robin
         * allocation.
         *
         * NOTE: It Just Happens to line up with the default
         * RSS allocation method.
         */

        /* Warning FM follows */
        uint32_t reta = 0;
        for (int i = 0; i < 128; i++) {
                const int shift = 0; /* XXXRO */
                int queue_id = i % sc->sc_nqueues;
                /* Adjust if required */
                queue_id <<= shift;

                /*
                 * The low 8 bits are for hash value (n+0);
                 * The next 8 bits are for hash value (n+1), etc.
                 */
                reta >>= 8;
                reta |= ((uint32_t)queue_id) << 24;
                if ((i & 3) == 3) {
                        IGC_WRITE_REG(hw, IGC_RETA(i >> 2), reta);
                        reta = 0;
                }
        }

        /*
         * MRQC: Multiple Receive Queues Command
         * Set queuing to RSS control, number depends on the device.
         */

        /* Set up random bits */
        uint32_t rss_key[RSS_KEYSIZE / sizeof(uint32_t)];
        rss_getkey((uint8_t *)rss_key);

        /* Now fill our hash function seeds */
        for (int i = 0; i < __arraycount(rss_key); i++)
                IGC_WRITE_REG_ARRAY(hw, IGC_RSSRK(0), i, rss_key[i]);

        /*
         * Configure the RSS fields to hash upon.
         */
        uint32_t mrqc = IGC_MRQC_ENABLE_RSS_4Q;
        mrqc |= IGC_MRQC_RSS_FIELD_IPV4 | IGC_MRQC_RSS_FIELD_IPV4_TCP;
        mrqc |= IGC_MRQC_RSS_FIELD_IPV6 | IGC_MRQC_RSS_FIELD_IPV6_TCP;
        mrqc |= IGC_MRQC_RSS_FIELD_IPV6_TCP_EX;

        IGC_WRITE_REG(hw, IGC_MRQC, mrqc);
}

/*
 * igc_get_hw_control sets the {CTRL_EXT|FWSM}:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means
 * that the driver is loaded. For AMT version type f/w
 * this means that the network i/f is open.
 */
static void
igc_get_hw_control(struct igc_softc *sc)
{
        const uint32_t ctrl_ext = IGC_READ_REG(&sc->hw, IGC_CTRL_EXT);

        IGC_WRITE_REG(&sc->hw, IGC_CTRL_EXT, ctrl_ext | IGC_CTRL_EXT_DRV_LOAD);
}

/*
 * igc_release_hw_control resets {CTRL_EXT|FWSM}:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that
 * the driver is no longer loaded. For AMT versions of the
 * f/w this means that the network i/f is closed.
 */
static void
igc_release_hw_control(struct igc_softc *sc)
{
        const uint32_t ctrl_ext = IGC_READ_REG(&sc->hw, IGC_CTRL_EXT);

        IGC_WRITE_REG(&sc->hw, IGC_CTRL_EXT, ctrl_ext & ~IGC_CTRL_EXT_DRV_LOAD);
}

static int
igc_is_valid_ether_addr(uint8_t *addr)
{
        const char zero_addr[6] = { 0, 0, 0, 0, 0, 0 };

        if ((addr[0] & 1) || !bcmp(addr, zero_addr, ETHER_ADDR_LEN))
                return 0;

        return 1;
}

static void
igc_print_devinfo(struct igc_softc *sc)
{
        device_t dev = sc->sc_dev;
        struct igc_hw *hw = &sc->hw;
        struct igc_phy_info *phy = &hw->phy;
        u_int oui, model, rev;
        uint16_t id1, id2, nvm_ver, phy_ver, etk_lo, etk_hi;
        char descr[MII_MAX_DESCR_LEN];

        /* Print PHY Info */
        id1 = phy->id >> 16;
        /* The revision field in phy->id is cleard and it's in phy->revision */
        id2 = (phy->id & 0xfff0) | phy->revision;
        oui = MII_OUI(id1, id2);
        model = MII_MODEL(id2);
        rev = MII_REV(id2);
        mii_get_descr(descr, sizeof(descr), oui, model);
        if (descr[0])
                aprint_normal_dev(dev, "PHY: %s, rev. %d",
                    descr, rev);
        else
                aprint_normal_dev(dev,
                    "PHY OUI 0x%06x, model 0x%04x, rev. %d",
                    oui, model, rev);

        /* PHY FW version */
        phy->ops.read_reg(hw, 0x1e, &phy_ver);
        aprint_normal(", PHY FW version 0x%04hx\n", phy_ver);

        /* NVM version */
        hw->nvm.ops.read(hw, NVM_VERSION, 1, &nvm_ver);

        /* EtrackID */
        hw->nvm.ops.read(hw, NVM_ETKID_LO, 1, &etk_lo);
        hw->nvm.ops.read(hw, NVM_ETKID_HI, 1, &etk_hi);

        aprint_normal_dev(dev,
            "NVM image version %x.%02x, EtrackID %04hx%04hx\n",
            (nvm_ver & NVM_VERSION_MAJOR) >> NVM_VERSION_MAJOR_SHIFT,
            nvm_ver & NVM_VERSION_MINOR, etk_hi, etk_lo);
}

/* Module interface */

MODULE(MODULE_CLASS_DRIVER, if_igc, "pci");
 
#ifdef _MODULE
#include "ioconf.c"
#endif
 
static int
if_igc_modcmd(modcmd_t cmd, void *opaque) 
{
        int error = 0;
 
        switch (cmd) { 
        case MODULE_CMD_INIT:
#ifdef _MODULE
                error = config_init_component(cfdriver_ioconf_igc,
                    cfattach_ioconf_igc, cfdata_ioconf_igc);
#endif
                return error;
        case MODULE_CMD_FINI:
#ifdef _MODULE
                error = config_fini_component(cfdriver_ioconf_igc,
                    cfattach_ioconf_igc, cfdata_ioconf_igc);
#endif
                return error;
        default:
                return ENOTTY;
        }
}