xref: /src/sys/dev/marvell/if_gfe.c

/*	if_gfe.c,v 1.24.2.1 2007/11/06 23:28:17 matt Exp	*/

/*
 * Copyright (c) 2002 Allegro Networks, Inc., Wasabi Systems, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed for the NetBSD Project by
 *      Allegro Networks, Inc., and Wasabi Systems, Inc.
 * 4. The name of Allegro Networks, Inc. may not be used to endorse
 *    or promote products derived from this software without specific prior
 *    written permission.
 * 5. The name of Wasabi Systems, Inc. may not be used to endorse
 *    or promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY ALLEGRO NETWORKS, INC. AND
 * WASABI SYSTEMS, INC. ``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 EITHER ALLEGRO NETWORKS, INC. OR WASABI SYSTEMS, INC.
 * 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.
 */

/*
 * if_gfe.c -- GT ethernet MAC driver
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "if_gfe.c,v 1.24.2.1 2007/11/06 23:28:17 matt Exp");

#include "opt_inet.h"
#include "bpfilter.h"

#include <sys/param.h>
#include <sys/types.h>
#include <sys/inttypes.h>
#include <sys/queue.h>

#include <uvm/uvm_extern.h>

#include <sys/callout.h>
#include <sys/device.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/mbuf.h>
#include <sys/socket.h>

#include <sys/bus.h>

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

#ifdef INET
#include <netinet/in.h>
#include <netinet/if_inarp.h>
#endif
#if NBPFILTER > 0
#include <net/bpf.h>
#endif

#include <dev/mii/miivar.h>

#include <dev/marvell/gtintrreg.h>
#include <dev/marvell/gtethreg.h>

#include <dev/marvell/gtvar.h>
#include <dev/marvell/if_gfevar.h>

#define	GE_READ(sc, reg) \
	bus_space_read_4((sc)->sc_gt_memt, (sc)->sc_memh, ETH__ ## reg)
#define	GE_WRITE(sc, reg, v) \
	bus_space_write_4((sc)->sc_gt_memt, (sc)->sc_memh, ETH__ ## reg, (v))

#define	GE_DEBUG
#if 0
#define	GE_NOHASH
#define	GE_NORX
#endif

#ifdef GE_DEBUG
#define	GE_DPRINTF(sc, a)	do \
				  if ((sc)->sc_ec.ec_if.if_flags & IFF_DEBUG) \
				    printf a; \
				while (0)
#define	GE_FUNC_ENTER(sc, func)	GE_DPRINTF(sc, ("[" func))
#define	GE_FUNC_EXIT(sc, str)	GE_DPRINTF(sc, (str "]"))
#else
#define	GE_DPRINTF(sc, a)	do { } while (0)
#define	GE_FUNC_ENTER(sc, func)	do { } while (0)
#define	GE_FUNC_EXIT(sc, str)	do { } while (0)
#endif
enum gfe_whack_op {
	GE_WHACK_START,		GE_WHACK_RESTART,
	GE_WHACK_CHANGE,	GE_WHACK_STOP
};

enum gfe_hash_op {
	GE_HASH_ADD,		GE_HASH_REMOVE,
};

#if 1
#define	htogt32(a)		htobe32(a)
#define	gt32toh(a)		be32toh(a)
#else
#define	htogt32(a)		htole32(a)
#define	gt32toh(a)		le32toh(a)
#endif

#define GE_RXDSYNC(sc, rxq, n, ops) \
	bus_dmamap_sync((sc)->sc_dmat, (rxq)->rxq_desc_mem.gdm_map, \
	    (n) * sizeof((rxq)->rxq_descs[0]), sizeof((rxq)->rxq_descs[0]), \
	    (ops))
#define	GE_RXDPRESYNC(sc, rxq, n) \
	GE_RXDSYNC(sc, rxq, n, BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE)
#define	GE_RXDPOSTSYNC(sc, rxq, n) \
	GE_RXDSYNC(sc, rxq, n, BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE)

#define GE_TXDSYNC(sc, txq, n, ops) \
	bus_dmamap_sync((sc)->sc_dmat, (txq)->txq_desc_mem.gdm_map, \
	    (n) * sizeof((txq)->txq_descs[0]), sizeof((txq)->txq_descs[0]), \
	    (ops))
#define	GE_TXDPRESYNC(sc, txq, n) \
	GE_TXDSYNC(sc, txq, n, BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE)
#define	GE_TXDPOSTSYNC(sc, txq, n) \
	GE_TXDSYNC(sc, txq, n, BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE)

#define	STATIC

STATIC int gfe_match (struct device *, struct cfdata *, void *);
STATIC void gfe_attach (struct device *, struct device *, void *);

STATIC int gfe_dmamem_alloc(struct gfe_softc *, struct gfe_dmamem *, int,
	size_t, int);
STATIC void gfe_dmamem_free(struct gfe_softc *, struct gfe_dmamem *);

STATIC int gfe_ifioctl (struct ifnet *, u_long, void *);
STATIC void gfe_ifstart (struct ifnet *);
STATIC void gfe_ifwatchdog (struct ifnet *);

STATIC int gfe_mii_read (struct device *, int, int);
STATIC void gfe_mii_write (struct device *, int, int, int);
STATIC void gfe_mii_statchg (struct device *);

STATIC void gfe_tick(void *arg);

STATIC void gfe_tx_restart(void *);
STATIC int gfe_tx_enqueue(struct gfe_softc *, enum gfe_txprio);
STATIC uint32_t gfe_tx_done(struct gfe_softc *, enum gfe_txprio, uint32_t);
STATIC void gfe_tx_cleanup(struct gfe_softc *, enum gfe_txprio, int);
STATIC int gfe_tx_txqalloc(struct gfe_softc *, enum gfe_txprio);
STATIC int gfe_tx_start(struct gfe_softc *, enum gfe_txprio);
STATIC void gfe_tx_stop(struct gfe_softc *, enum gfe_whack_op);

STATIC void gfe_rx_cleanup(struct gfe_softc *, enum gfe_rxprio);
STATIC void gfe_rx_get(struct gfe_softc *, enum gfe_rxprio);
STATIC int gfe_rx_prime(struct gfe_softc *);
STATIC uint32_t gfe_rx_process(struct gfe_softc *, uint32_t, uint32_t);
STATIC int gfe_rx_rxqalloc(struct gfe_softc *, enum gfe_rxprio);
STATIC int gfe_rx_rxqinit(struct gfe_softc *, enum gfe_rxprio);
STATIC void gfe_rx_stop(struct gfe_softc *, enum gfe_whack_op);

STATIC int gfe_intr(void *);

STATIC int gfe_whack(struct gfe_softc *, enum gfe_whack_op);

STATIC int gfe_hash_compute(struct gfe_softc *, const uint8_t [ETHER_ADDR_LEN]);
STATIC int gfe_hash_entry_op(struct gfe_softc *, enum gfe_hash_op,
	enum gfe_rxprio, const uint8_t [ETHER_ADDR_LEN]);
STATIC int gfe_hash_multichg(struct ethercom *, const struct ether_multi *,
	u_long);
STATIC int gfe_hash_fill(struct gfe_softc *);
STATIC int gfe_hash_alloc(struct gfe_softc *);

/* Linkup to the rest of the kernel */
CFATTACH_DECL(gfe, sizeof(struct gfe_softc),
    gfe_match, gfe_attach, NULL, NULL);

extern struct cfdriver gfe_cd;

int
gfe_match(struct device *parent, struct cfdata *cf, void *aux)
{
	struct gt_softc *gt = (struct gt_softc *) parent;
	struct gt_attach_args *ga = aux;
	uint8_t enaddr[6];

	if (!GT_ETHEROK(gt, ga, &gfe_cd))
		return 0;

	if (gtget_macaddr(gt, ga->ga_unit, enaddr) < 0)
		return 0;

	if (enaddr[0] == 0 && enaddr[1] == 0 && enaddr[2] == 0 &&
	    enaddr[3] == 0 && enaddr[4] == 0 && enaddr[5] == 0)
		return 0;

	return 1;
}

/*
 * Attach this instance, and then all the sub-devices
 */
void
gfe_attach(struct device *parent, struct device *self, void *aux)
{
	struct gt_attach_args * const ga = aux;
	struct gt_softc * const gt = device_private(parent);
	struct gfe_softc * const sc = device_private(self);
	struct ifnet * const ifp = &sc->sc_ec.ec_if;
	uint32_t data;
	uint8_t enaddr[6];
	int phyaddr;
	uint32_t sdcr;
	int error;

	GT_ETHERFOUND(gt, ga);

	sc->sc_gt_memt = ga->ga_memt;
	sc->sc_gt_memh = ga->ga_memh;
	sc->sc_dmat = ga->ga_dmat;
	sc->sc_macno = ga->ga_unit;

	if (bus_space_subregion(sc->sc_gt_memt, sc->sc_gt_memh,
		    ETH_BASE(sc->sc_macno), ETH_SIZE, &sc->sc_memh)) {
		aprint_error(": failed to map registers\n");
	}

	callout_init(&sc->sc_co, 0);

	data = bus_space_read_4(sc->sc_gt_memt, sc->sc_gt_memh, ETH_EPAR);
	phyaddr = ETH_EPAR_PhyAD_GET(data, sc->sc_macno);

	gtget_macaddr(gt, sc->sc_macno, enaddr);

	sc->sc_pcr = GE_READ(sc, EPCR);
	sc->sc_pcxr = GE_READ(sc, EPCXR);
	sc->sc_intrmask = GE_READ(sc, EIMR) | ETH_IR_MIIPhySTC;

	aprint_normal(": address %s", ether_sprintf(enaddr));

#if defined(DEBUG)
	aprint_normal(", pcr %#x, pcxr %#x", sc->sc_pcr, sc->sc_pcxr);
#endif

	sc->sc_pcxr &= ~ETH_EPCXR_PRIOrx_Override;
	if (device_cfdata(&sc->sc_dev)->cf_flags & 1) {
		aprint_normal(", phy %d (rmii)", phyaddr);
		sc->sc_pcxr |= ETH_EPCXR_RMIIEn;
	} else {
		aprint_normal(", phy %d (mii)", phyaddr);
		sc->sc_pcxr &= ~ETH_EPCXR_RMIIEn;
	}
	if (device_cfdata(&sc->sc_dev)->cf_flags & 2)
		sc->sc_flags |= GE_NOFREE;
	sc->sc_pcxr &= ~(3 << 14);
	sc->sc_pcxr |= (ETH_EPCXR_MFL_1536 << 14);

	if (sc->sc_pcr & ETH_EPCR_EN) {
		int tries = 1000;
		/*
		 * Abort transmitter and receiver and wait for them to quiese
		 */
		GE_WRITE(sc, ESDCMR, ETH_ESDCMR_AR|ETH_ESDCMR_AT);
		do {
			delay(100);
		} while (tries-- > 0 && (GE_READ(sc, ESDCMR) & (ETH_ESDCMR_AR|ETH_ESDCMR_AT)));
	}

	sc->sc_pcr &= ~(ETH_EPCR_EN | ETH_EPCR_RBM | ETH_EPCR_PM | ETH_EPCR_PBF);

#if defined(DEBUG)
	aprint_normal(", pcr %#x, pcxr %#x", sc->sc_pcr, sc->sc_pcxr);
#endif

	/*
	 * Now turn off the GT.  If it didn't quiese, too ***ing bad.
	 */
	GE_WRITE(sc, EPCR, sc->sc_pcr);
	GE_WRITE(sc, EIMR, sc->sc_intrmask);
	sdcr = GE_READ(sc, ESDCR);
	ETH_ESDCR_BSZ_SET(sdcr, ETH_ESDCR_BSZ_4);
	sdcr |= ETH_ESDCR_RIFB;
	GE_WRITE(sc, ESDCR, sdcr);
	sc->sc_max_frame_length = 1536;

	aprint_normal("\n");
	sc->sc_mii.mii_ifp = ifp;
	sc->sc_mii.mii_readreg = gfe_mii_read;
	sc->sc_mii.mii_writereg = gfe_mii_write;
	sc->sc_mii.mii_statchg = gfe_mii_statchg;

	sc->sc_ec.ec_mii = &sc->sc_mii;
	ifmedia_init(&sc->sc_mii.mii_media, 0, ether_mediachange,
		ether_mediastatus);

	mii_attach(&sc->sc_dev, &sc->sc_mii, 0xffffffff, phyaddr,
		MII_OFFSET_ANY, MIIF_NOISOLATE);
	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
	} else {
		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
	}

	strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
	ifp->if_softc = sc;
	/* ifp->if_mowner = &sc->sc_mowner; */
	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
#if 0
	ifp->if_flags |= IFF_DEBUG;
#endif
	ifp->if_ioctl = gfe_ifioctl;
	ifp->if_start = gfe_ifstart;
	ifp->if_watchdog = gfe_ifwatchdog;

	if (sc->sc_flags & GE_NOFREE) {
		error = gfe_rx_rxqalloc(sc, GE_RXPRIO_HI);
		if (!error)
			error = gfe_rx_rxqalloc(sc, GE_RXPRIO_MEDHI);
		if (!error)
			error = gfe_rx_rxqalloc(sc, GE_RXPRIO_MEDLO);
		if (!error)
			error = gfe_rx_rxqalloc(sc, GE_RXPRIO_LO);
		if (!error)
			error = gfe_tx_txqalloc(sc, GE_TXPRIO_HI);
		if (!error)
			error = gfe_hash_alloc(sc);
		if (error)
			aprint_error(
			    "%s: failed to allocate resources: %d\n",
			    ifp->if_xname, error);
	}

	if_attach(ifp);
	ether_ifattach(ifp, enaddr);
#if NBPFILTER > 0
	bpfattach(ifp, DLT_EN10MB, sizeof(struct ether_header));
#endif
#if NRND > 0
	rnd_attach_source(&sc->sc_rnd_source, self->dv_xname, RND_TYPE_NET, 0);
#endif
	intr_establish(IRQ_ETH0 + sc->sc_macno, IST_LEVEL, IPL_NET,
	    gfe_intr, sc);
}

int
gfe_dmamem_alloc(struct gfe_softc *sc, struct gfe_dmamem *gdm, int maxsegs,
	size_t size, int flags)
{
	int error = 0;
	GE_FUNC_ENTER(sc, "gfe_dmamem_alloc");

	KASSERT(gdm->gdm_kva == NULL);
	gdm->gdm_size = size;
	gdm->gdm_maxsegs = maxsegs;

	error = bus_dmamem_alloc(sc->sc_dmat, gdm->gdm_size, PAGE_SIZE,
	    gdm->gdm_size, gdm->gdm_segs, gdm->gdm_maxsegs, &gdm->gdm_nsegs,
	    BUS_DMA_NOWAIT);
	if (error)
		goto fail;

	error = bus_dmamem_map(sc->sc_dmat, gdm->gdm_segs, gdm->gdm_nsegs,
	    gdm->gdm_size, &gdm->gdm_kva, flags | BUS_DMA_NOWAIT);
	if (error)
		goto fail;

	error = bus_dmamap_create(sc->sc_dmat, gdm->gdm_size, gdm->gdm_nsegs,
	    gdm->gdm_size, 0, BUS_DMA_ALLOCNOW|BUS_DMA_NOWAIT, &gdm->gdm_map);
	if (error)
		goto fail;

	error = bus_dmamap_load(sc->sc_dmat, gdm->gdm_map, gdm->gdm_kva,
	    gdm->gdm_size, NULL, BUS_DMA_NOWAIT);
	if (error)
		goto fail;

	/* invalidate from cache */
	bus_dmamap_sync(sc->sc_dmat, gdm->gdm_map, 0, gdm->gdm_size,
	    BUS_DMASYNC_PREREAD);
fail:
	if (error) {
		gfe_dmamem_free(sc, gdm);
		GE_DPRINTF(sc, (":err=%d", error));
	}
	GE_DPRINTF(sc, (":kva=%p/%#x,map=%p,nsegs=%d,pa=%x/%x",
	    gdm->gdm_kva, gdm->gdm_size, gdm->gdm_map, gdm->gdm_map->dm_nsegs,
	    gdm->gdm_map->dm_segs->ds_addr, gdm->gdm_map->dm_segs->ds_len));
	GE_FUNC_EXIT(sc, "");
	return error;
}

void
gfe_dmamem_free(struct gfe_softc *sc, struct gfe_dmamem *gdm)
{
	GE_FUNC_ENTER(sc, "gfe_dmamem_free");
	if (gdm->gdm_map)
		bus_dmamap_destroy(sc->sc_dmat, gdm->gdm_map);
	if (gdm->gdm_kva)
		bus_dmamem_unmap(sc->sc_dmat, gdm->gdm_kva, gdm->gdm_size);
	if (gdm->gdm_nsegs > 0)
		bus_dmamem_free(sc->sc_dmat, gdm->gdm_segs, gdm->gdm_nsegs);
	gdm->gdm_map = NULL;
	gdm->gdm_kva = NULL;
	gdm->gdm_nsegs = 0;
	GE_FUNC_EXIT(sc, "");
}

int
gfe_ifioctl(struct ifnet *ifp, u_long cmd, void *data)
{
	struct gfe_softc * const sc = ifp->if_softc;
	struct ifreq *ifr = (struct ifreq *) data;
	struct ifaddr *ifa = (struct ifaddr *) data;
	int s, error = 0;

	GE_FUNC_ENTER(sc, "gfe_ifioctl");
	s = splnet();

	switch (cmd) {
	case SIOCSIFADDR:
		ifp->if_flags |= IFF_UP;
		switch (ifa->ifa_addr->sa_family) {
#ifdef INET
		case AF_INET:
			error = gfe_whack(sc, GE_WHACK_START);
			if (error == 0)
				arp_ifinit(ifp, ifa);
			break;
#endif
		default:
			error = gfe_whack(sc, GE_WHACK_START);
			break;
		}
		break;

	case SIOCSIFFLAGS:
		switch (ifp->if_flags & (IFF_UP|IFF_RUNNING)) {
		case IFF_UP|IFF_RUNNING:/* active->active, update */
			error = gfe_whack(sc, GE_WHACK_CHANGE);
			break;
		case IFF_RUNNING:	/* not up, so we stop */
			error = gfe_whack(sc, GE_WHACK_STOP);
			break;
		case IFF_UP:		/* not running, so we start */
			error = gfe_whack(sc, GE_WHACK_START);
			break;
		case 0:			/* idle->idle: do nothing */
			break;
		}
		break;

	case SIOCSIFMEDIA:
	case SIOCGIFMEDIA:
	case SIOCADDMULTI:
	case SIOCDELMULTI:
		if ((error = ether_ioctl(ifp, cmd, data)) == ENETRESET) {
			if (ifp->if_flags & IFF_RUNNING)
				error = gfe_whack(sc, GE_WHACK_CHANGE);
			else
				error = 0;
		}
		break;

	case SIOCSIFMTU:
		if (ifr->ifr_mtu > ETHERMTU || ifr->ifr_mtu < ETHERMIN) {
			error = EINVAL;
			break;
		}
		if ((error = ifioctl_common(ifp, cmd, data)) == ENETRESET)
			error = 0;
		break;

	default:
		error = EINVAL;
		break;
	}
	splx(s);
	GE_FUNC_EXIT(sc, "");
	return error;
}

void
gfe_ifstart(struct ifnet *ifp)
{
	struct gfe_softc * const sc = ifp->if_softc;
	struct mbuf *m;

	GE_FUNC_ENTER(sc, "gfe_ifstart");

	if ((ifp->if_flags & IFF_RUNNING) == 0) {
		GE_FUNC_EXIT(sc, "$");
		return;
	}

	for (;;) {
		IF_DEQUEUE(&ifp->if_snd, m);
		if (m == NULL) {
			ifp->if_flags &= ~IFF_OACTIVE;
			GE_FUNC_EXIT(sc, "");
			return;
		}

		/*
		 * No space in the pending queue?  try later.
		 */
		if (IF_QFULL(&sc->sc_txq[GE_TXPRIO_HI].txq_pendq))
			break;

		/*
		 * Try to enqueue a mbuf to the device. If that fails, we
		 * can always try to map the next mbuf.
		 */
		IF_ENQUEUE(&sc->sc_txq[GE_TXPRIO_HI].txq_pendq, m);
		GE_DPRINTF(sc, (">"));
#ifndef GE_NOTX
		(void) gfe_tx_enqueue(sc, GE_TXPRIO_HI);
#endif
	}

	/*
	 * Attempt to queue the mbuf for send failed.
	 */
	IF_PREPEND(&ifp->if_snd, m);
	ifp->if_flags |= IFF_OACTIVE;
	GE_FUNC_EXIT(sc, "%%");
}

void
gfe_ifwatchdog(struct ifnet *ifp)
{
	struct gfe_softc * const sc = ifp->if_softc;
	struct gfe_txqueue * const txq = &sc->sc_txq[GE_TXPRIO_HI];

	GE_FUNC_ENTER(sc, "gfe_ifwatchdog");
	printf("%s: device timeout", sc->sc_dev.dv_xname);
	if (ifp->if_flags & IFF_RUNNING) {
		uint32_t curtxdnum = (bus_space_read_4(sc->sc_gt_memt, sc->sc_gt_memh, txq->txq_ectdp) - txq->txq_desc_busaddr) / sizeof(txq->txq_descs[0]);
		GE_TXDPOSTSYNC(sc, txq, txq->txq_fi);
		GE_TXDPOSTSYNC(sc, txq, curtxdnum);
		printf(" (fi=%d(%#x),lo=%d,cur=%d(%#x),icm=%#x) ",
		    txq->txq_fi, txq->txq_descs[txq->txq_fi].ed_cmdsts,
		    txq->txq_lo, curtxdnum, txq->txq_descs[curtxdnum].ed_cmdsts,
		    GE_READ(sc, EICR));
		GE_TXDPRESYNC(sc, txq, txq->txq_fi);
		GE_TXDPRESYNC(sc, txq, curtxdnum);
	}
	printf("\n");
	ifp->if_oerrors++;
	(void) gfe_whack(sc, GE_WHACK_RESTART);
	GE_FUNC_EXIT(sc, "");
}

int
gfe_rx_rxqalloc(struct gfe_softc *sc, enum gfe_rxprio rxprio)
{
	struct gfe_rxqueue * const rxq = &sc->sc_rxq[rxprio];
	int error;

	GE_FUNC_ENTER(sc, "gfe_rx_rxqalloc");
	GE_DPRINTF(sc, ("(%d)", rxprio));

	error = gfe_dmamem_alloc(sc, &rxq->rxq_desc_mem, 1,
	    GE_RXDESC_MEMSIZE, BUS_DMA_NOCACHE);
	if (error) {
		GE_FUNC_EXIT(sc, "!!");
		return error;
	}

	error = gfe_dmamem_alloc(sc, &rxq->rxq_buf_mem, GE_RXBUF_NSEGS,
	    GE_RXBUF_MEMSIZE, 0);
	if (error) {
		GE_FUNC_EXIT(sc, "!!!");
		return error;
	}
	GE_FUNC_EXIT(sc, "");
	return error;
}

int
gfe_rx_rxqinit(struct gfe_softc *sc, enum gfe_rxprio rxprio)
{
	struct gfe_rxqueue * const rxq = &sc->sc_rxq[rxprio];
	volatile struct gt_eth_desc *rxd;
	const bus_dma_segment_t *ds;
	int idx;
	bus_addr_t nxtaddr;
	bus_size_t boff;

	GE_FUNC_ENTER(sc, "gfe_rx_rxqinit");
	GE_DPRINTF(sc, ("(%d)", rxprio));

	if ((sc->sc_flags & GE_NOFREE) == 0) {
		int error = gfe_rx_rxqalloc(sc, rxprio);
		if (error) {
			GE_FUNC_EXIT(sc, "!");
			return error;
		}
	} else {
		KASSERT(rxq->rxq_desc_mem.gdm_kva != NULL);
		KASSERT(rxq->rxq_buf_mem.gdm_kva != NULL);
	}

	memset(rxq->rxq_desc_mem.gdm_kva, 0, GE_RXDESC_MEMSIZE);

	rxq->rxq_descs =
	    (volatile struct gt_eth_desc *) rxq->rxq_desc_mem.gdm_kva;
	rxq->rxq_desc_busaddr = rxq->rxq_desc_mem.gdm_map->dm_segs[0].ds_addr;
	rxq->rxq_bufs = (struct gfe_rxbuf *) rxq->rxq_buf_mem.gdm_kva;
	rxq->rxq_fi = 0;
	rxq->rxq_active = GE_RXDESC_MAX;
	for (idx = 0, rxd = rxq->rxq_descs,
		boff = 0, ds = rxq->rxq_buf_mem.gdm_map->dm_segs,
		nxtaddr = rxq->rxq_desc_busaddr + sizeof(*rxd);
	     idx < GE_RXDESC_MAX;
	     idx++, rxd++, nxtaddr += sizeof(*rxd)) {
		rxd->ed_lencnt = htogt32(GE_RXBUF_SIZE << 16);
		rxd->ed_cmdsts = htogt32(RX_CMD_F|RX_CMD_L|RX_CMD_O|RX_CMD_EI);
		rxd->ed_bufptr = htogt32(ds->ds_addr + boff);
		/*
		 * update the nxtptr to point to the next txd.
		 */
		if (idx == GE_RXDESC_MAX - 1)
			nxtaddr = rxq->rxq_desc_busaddr;
		rxd->ed_nxtptr = htogt32(nxtaddr);
		boff += GE_RXBUF_SIZE;
		if (boff == ds->ds_len) {
			ds++;
			boff = 0;
		}
	}
	bus_dmamap_sync(sc->sc_dmat, rxq->rxq_desc_mem.gdm_map, 0,
			rxq->rxq_desc_mem.gdm_map->dm_mapsize,
			BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
	bus_dmamap_sync(sc->sc_dmat, rxq->rxq_buf_mem.gdm_map, 0,
			rxq->rxq_buf_mem.gdm_map->dm_mapsize,
			BUS_DMASYNC_PREREAD);

	rxq->rxq_intrbits = ETH_IR_RxBuffer|ETH_IR_RxError;
	switch (rxprio) {
	case GE_RXPRIO_HI:
		rxq->rxq_intrbits |= ETH_IR_RxBuffer_3|ETH_IR_RxError_3;
		rxq->rxq_efrdp = ETH_EFRDP3(sc->sc_macno);
		rxq->rxq_ecrdp = ETH_ECRDP3(sc->sc_macno);
		break;
	case GE_RXPRIO_MEDHI:
		rxq->rxq_intrbits |= ETH_IR_RxBuffer_2|ETH_IR_RxError_2;
		rxq->rxq_efrdp = ETH_EFRDP2(sc->sc_macno);
		rxq->rxq_ecrdp = ETH_ECRDP2(sc->sc_macno);
		break;
	case GE_RXPRIO_MEDLO:
		rxq->rxq_intrbits |= ETH_IR_RxBuffer_1|ETH_IR_RxError_1;
		rxq->rxq_efrdp = ETH_EFRDP1(sc->sc_macno);
		rxq->rxq_ecrdp = ETH_ECRDP1(sc->sc_macno);
		break;
	case GE_RXPRIO_LO:
		rxq->rxq_intrbits |= ETH_IR_RxBuffer_0|ETH_IR_RxError_0;
		rxq->rxq_efrdp = ETH_EFRDP0(sc->sc_macno);
		rxq->rxq_ecrdp = ETH_ECRDP0(sc->sc_macno);
		break;
	}
	GE_FUNC_EXIT(sc, "");
	return 0;
}

void
gfe_rx_get(struct gfe_softc *sc, enum gfe_rxprio rxprio)
{
	struct ifnet * const ifp = &sc->sc_ec.ec_if;
	struct gfe_rxqueue * const rxq = &sc->sc_rxq[rxprio];
	struct mbuf *m = rxq->rxq_curpkt;

	GE_FUNC_ENTER(sc, "gfe_rx_get");
	GE_DPRINTF(sc, ("(%d)", rxprio));

	while (rxq->rxq_active > 0) {
		volatile struct gt_eth_desc *rxd = &rxq->rxq_descs[rxq->rxq_fi];
		struct gfe_rxbuf *rxb = &rxq->rxq_bufs[rxq->rxq_fi];
		const struct ether_header *eh;
		unsigned int cmdsts;
		size_t buflen;

		GE_RXDPOSTSYNC(sc, rxq, rxq->rxq_fi);
		cmdsts = gt32toh(rxd->ed_cmdsts);
		GE_DPRINTF(sc, (":%d=%#x", rxq->rxq_fi, cmdsts));
		rxq->rxq_cmdsts = cmdsts;
		/*
		 * Sometimes the GE "forgets" to reset the ownership bit.
		 * But if the length has been rewritten, the packet is ours
		 * so pretend the O bit is set.
		 */
		buflen = gt32toh(rxd->ed_lencnt) & 0xffff;
		if ((cmdsts & RX_CMD_O) && buflen == 0) {
			GE_RXDPRESYNC(sc, rxq, rxq->rxq_fi);
			break;
		}

		/*
		 * If this is not a single buffer packet with no errors
		 * or for some reason it's bigger than our frame size,
		 * ignore it and go to the next packet.
		 */
		if ((cmdsts & (RX_CMD_F|RX_CMD_L|RX_STS_ES)) !=
			    (RX_CMD_F|RX_CMD_L) ||
		    buflen > sc->sc_max_frame_length) {
			GE_DPRINTF(sc, ("!"));
			--rxq->rxq_active;
			ifp->if_ipackets++;
			ifp->if_ierrors++;
			goto give_it_back;
		}

		/* CRC is included with the packet; trim it off. */
		buflen -= ETHER_CRC_LEN;

		if (m == NULL) {
			MGETHDR(m, M_DONTWAIT, MT_DATA);
			if (m == NULL) {
				GE_DPRINTF(sc, ("?"));
				break;
			}
		}
		if ((m->m_flags & M_EXT) == 0 && buflen > MHLEN - 2) {
			MCLGET(m, M_DONTWAIT);
			if ((m->m_flags & M_EXT) == 0) {
				GE_DPRINTF(sc, ("?"));
				break;
			}
		}
		m->m_data += 2;
		m->m_len = 0;
		m->m_pkthdr.len = 0;
		m->m_pkthdr.rcvif = ifp;
		rxq->rxq_cmdsts = cmdsts;
		--rxq->rxq_active;

		bus_dmamap_sync(sc->sc_dmat, rxq->rxq_buf_mem.gdm_map,
		    rxq->rxq_fi * sizeof(*rxb), buflen, BUS_DMASYNC_POSTREAD);

		KASSERT(m->m_len == 0 && m->m_pkthdr.len == 0);
		memcpy(m->m_data + m->m_len, rxb->rb_data, buflen);
		m->m_len = buflen;
		m->m_pkthdr.len = buflen;

		ifp->if_ipackets++;
#if NBPFILTER > 0
		if (ifp->if_bpf != NULL)
			bpf_mtap(ifp->if_bpf, m);
#endif

		eh = (const struct ether_header *) m->m_data;
		if ((ifp->if_flags & IFF_PROMISC) ||
		    (rxq->rxq_cmdsts & RX_STS_M) == 0 ||
		    (rxq->rxq_cmdsts & RX_STS_HE) ||
		    (eh->ether_dhost[0] & 1) != 0 ||
		    memcmp(eh->ether_dhost, CLLADDR(ifp->if_sadl),
			ETHER_ADDR_LEN) == 0) {
			(*ifp->if_input)(ifp, m);
			m = NULL;
			GE_DPRINTF(sc, (">"));
		} else {
			m->m_len = 0;
			m->m_pkthdr.len = 0;
			GE_DPRINTF(sc, ("+"));
		}
		rxq->rxq_cmdsts = 0;

	   give_it_back:
		rxd->ed_lencnt &= ~0xffff;	/* zero out length */
		rxd->ed_cmdsts = htogt32(RX_CMD_F|RX_CMD_L|RX_CMD_O|RX_CMD_EI);
#if 0
		GE_DPRINTF(sc, ("([%d]->%08lx.%08lx.%08lx.%08lx)",
		    rxq->rxq_fi,
		    ((unsigned long *)rxd)[0], ((unsigned long *)rxd)[1],
		    ((unsigned long *)rxd)[2], ((unsigned long *)rxd)[3]));
#endif
		GE_RXDPRESYNC(sc, rxq, rxq->rxq_fi);
		if (++rxq->rxq_fi == GE_RXDESC_MAX)
			rxq->rxq_fi = 0;
		rxq->rxq_active++;
	}
	rxq->rxq_curpkt = m;
	GE_FUNC_EXIT(sc, "");
}

uint32_t
gfe_rx_process(struct gfe_softc *sc, uint32_t cause, uint32_t intrmask)
{
	struct ifnet * const ifp = &sc->sc_ec.ec_if;
	struct gfe_rxqueue *rxq;
	uint32_t rxbits;
#define	RXPRIO_DECODER	0xffffaa50
	GE_FUNC_ENTER(sc, "gfe_rx_process");

	rxbits = ETH_IR_RxBuffer_GET(cause);
	while (rxbits) {
		enum gfe_rxprio rxprio = (RXPRIO_DECODER >> (rxbits * 2)) & 3;
		GE_DPRINTF(sc, ("%1x", rxbits));
		rxbits &= ~(1 << rxprio);
		gfe_rx_get(sc, rxprio);
	}

	rxbits = ETH_IR_RxError_GET(cause);
	while (rxbits) {
		enum gfe_rxprio rxprio = (RXPRIO_DECODER >> (rxbits * 2)) & 3;
		uint32_t masks[(GE_RXDESC_MAX + 31) / 32];
		int idx;
		rxbits &= ~(1 << rxprio);
		rxq = &sc->sc_rxq[rxprio];
		sc->sc_idlemask |= (rxq->rxq_intrbits & ETH_IR_RxBits);
		intrmask &= ~(rxq->rxq_intrbits & ETH_IR_RxBits);
		if ((sc->sc_tickflags & GE_TICK_RX_RESTART) == 0) {
			sc->sc_tickflags |= GE_TICK_RX_RESTART;
			callout_reset(&sc->sc_co, 1, gfe_tick, sc);
		}
		ifp->if_ierrors++;
		GE_DPRINTF(sc, ("%s: rx queue %d filled at %u\n",
		    sc->sc_dev.dv_xname, rxprio, rxq->rxq_fi));
		memset(masks, 0, sizeof(masks));
		bus_dmamap_sync(sc->sc_dmat, rxq->rxq_desc_mem.gdm_map,
		    0, rxq->rxq_desc_mem.gdm_size,
		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
		for (idx = 0; idx < GE_RXDESC_MAX; idx++) {
			volatile struct gt_eth_desc *rxd = &rxq->rxq_descs[idx];

			if (RX_CMD_O & gt32toh(rxd->ed_cmdsts))
				masks[idx/32] |= 1 << (idx & 31);
		}
		bus_dmamap_sync(sc->sc_dmat, rxq->rxq_desc_mem.gdm_map,
		    0, rxq->rxq_desc_mem.gdm_size,
		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
#if defined(DEBUG)
		printf("%s: rx queue %d filled at %u=%#x(%#x/%#x)\n",
		    sc->sc_dev.dv_xname, rxprio, rxq->rxq_fi,
		    rxq->rxq_cmdsts, masks[0], masks[1]);
#endif
	}
	if ((intrmask & ETH_IR_RxBits) == 0)
		intrmask &= ~(ETH_IR_RxBuffer|ETH_IR_RxError);

	GE_FUNC_EXIT(sc, "");
	return intrmask;
}

int
gfe_rx_prime(struct gfe_softc *sc)
{
	struct gfe_rxqueue *rxq;
	int error;

	GE_FUNC_ENTER(sc, "gfe_rx_prime");

	error = gfe_rx_rxqinit(sc, GE_RXPRIO_HI);
	if (error)
		goto bail;
	rxq = &sc->sc_rxq[GE_RXPRIO_HI];
	if ((sc->sc_flags & GE_RXACTIVE) == 0) {
		GE_WRITE(sc, EFRDP3, rxq->rxq_desc_busaddr);
		GE_WRITE(sc, ECRDP3, rxq->rxq_desc_busaddr);
	}
	sc->sc_intrmask |= rxq->rxq_intrbits;

	error = gfe_rx_rxqinit(sc, GE_RXPRIO_MEDHI);
	if (error)
		goto bail;
	if ((sc->sc_flags & GE_RXACTIVE) == 0) {
		rxq = &sc->sc_rxq[GE_RXPRIO_MEDHI];
		GE_WRITE(sc, EFRDP2, rxq->rxq_desc_busaddr);
		GE_WRITE(sc, ECRDP2, rxq->rxq_desc_busaddr);
		sc->sc_intrmask |= rxq->rxq_intrbits;
	}

	error = gfe_rx_rxqinit(sc, GE_RXPRIO_MEDLO);
	if (error)
		goto bail;
	if ((sc->sc_flags & GE_RXACTIVE) == 0) {
		rxq = &sc->sc_rxq[GE_RXPRIO_MEDLO];
		GE_WRITE(sc, EFRDP1, rxq->rxq_desc_busaddr);
		GE_WRITE(sc, ECRDP1, rxq->rxq_desc_busaddr);
		sc->sc_intrmask |= rxq->rxq_intrbits;
	}

	error = gfe_rx_rxqinit(sc, GE_RXPRIO_LO);
	if (error)
		goto bail;
	if ((sc->sc_flags & GE_RXACTIVE) == 0) {
		rxq = &sc->sc_rxq[GE_RXPRIO_LO];
		GE_WRITE(sc, EFRDP0, rxq->rxq_desc_busaddr);
		GE_WRITE(sc, ECRDP0, rxq->rxq_desc_busaddr);
		sc->sc_intrmask |= rxq->rxq_intrbits;
	}

  bail:
	GE_FUNC_EXIT(sc, "");
	return error;
}

void
gfe_rx_cleanup(struct gfe_softc *sc, enum gfe_rxprio rxprio)
{
	struct gfe_rxqueue *rxq = &sc->sc_rxq[rxprio];
	GE_FUNC_ENTER(sc, "gfe_rx_cleanup");
	if (rxq == NULL) {
		GE_FUNC_EXIT(sc, "");
		return;
	}

	if (rxq->rxq_curpkt)
		m_freem(rxq->rxq_curpkt);
	if ((sc->sc_flags & GE_NOFREE) == 0) {
		gfe_dmamem_free(sc, &rxq->rxq_desc_mem);
		gfe_dmamem_free(sc, &rxq->rxq_buf_mem);
	}
	GE_FUNC_EXIT(sc, "");
}

void
gfe_rx_stop(struct gfe_softc *sc, enum gfe_whack_op op)
{
	GE_FUNC_ENTER(sc, "gfe_rx_stop");
	sc->sc_flags &= ~GE_RXACTIVE;
	sc->sc_idlemask &= ~(ETH_IR_RxBits|ETH_IR_RxBuffer|ETH_IR_RxError);
	sc->sc_intrmask &= ~(ETH_IR_RxBits|ETH_IR_RxBuffer|ETH_IR_RxError);
	GE_WRITE(sc, EIMR, sc->sc_intrmask);
	GE_WRITE(sc, ESDCMR, ETH_ESDCMR_AR);
	do {
		delay(10);
	} while (GE_READ(sc, ESDCMR) & ETH_ESDCMR_AR);
	gfe_rx_cleanup(sc, GE_RXPRIO_HI);
	gfe_rx_cleanup(sc, GE_RXPRIO_MEDHI);
	gfe_rx_cleanup(sc, GE_RXPRIO_MEDLO);
	gfe_rx_cleanup(sc, GE_RXPRIO_LO);
	GE_FUNC_EXIT(sc, "");
}

void
gfe_tick(void *arg)
{
	struct gfe_softc * const sc = arg;
	uint32_t intrmask;
	unsigned int tickflags;
	int s;

	GE_FUNC_ENTER(sc, "gfe_tick");

	s = splnet();

	tickflags = sc->sc_tickflags;
	sc->sc_tickflags = 0;
	intrmask = sc->sc_intrmask;
	if (tickflags & GE_TICK_TX_IFSTART)
		gfe_ifstart(&sc->sc_ec.ec_if);
	if (tickflags & GE_TICK_RX_RESTART) {
		intrmask |= sc->sc_idlemask;
		if (sc->sc_idlemask & (ETH_IR_RxBuffer_3|ETH_IR_RxError_3)) {
			struct gfe_rxqueue *rxq = &sc->sc_rxq[GE_RXPRIO_HI];
			rxq->rxq_fi = 0;
			GE_WRITE(sc, EFRDP3, rxq->rxq_desc_busaddr);
			GE_WRITE(sc, ECRDP3, rxq->rxq_desc_busaddr);
		}
		if (sc->sc_idlemask & (ETH_IR_RxBuffer_2|ETH_IR_RxError_2)) {
			struct gfe_rxqueue *rxq = &sc->sc_rxq[GE_RXPRIO_MEDHI];
			rxq->rxq_fi = 0;
			GE_WRITE(sc, EFRDP2, rxq->rxq_desc_busaddr);
			GE_WRITE(sc, ECRDP2, rxq->rxq_desc_busaddr);
		}
		if (sc->sc_idlemask & (ETH_IR_RxBuffer_1|ETH_IR_RxError_1)) {
			struct gfe_rxqueue *rxq = &sc->sc_rxq[GE_RXPRIO_MEDLO];
			rxq->rxq_fi = 0;
			GE_WRITE(sc, EFRDP1, rxq->rxq_desc_busaddr);
			GE_WRITE(sc, ECRDP1, rxq->rxq_desc_busaddr);
		}
		if (sc->sc_idlemask & (ETH_IR_RxBuffer_0|ETH_IR_RxError_0)) {
			struct gfe_rxqueue *rxq = &sc->sc_rxq[GE_RXPRIO_LO];
			rxq->rxq_fi = 0;
			GE_WRITE(sc, EFRDP0, rxq->rxq_desc_busaddr);
			GE_WRITE(sc, ECRDP0, rxq->rxq_desc_busaddr);
		}
		sc->sc_idlemask = 0;
	}
	if (intrmask != sc->sc_intrmask) {
		sc->sc_intrmask = intrmask;
		GE_WRITE(sc, EIMR, sc->sc_intrmask);
	}
	gfe_intr(sc);
	splx(s);

	GE_FUNC_EXIT(sc, "");
}

int
gfe_tx_enqueue(struct gfe_softc *sc, enum gfe_txprio txprio)
{
	const int dcache_line_size = curcpu()->ci_ci.dcache_line_size;
	struct ifnet * const ifp = &sc->sc_ec.ec_if;
	struct gfe_txqueue * const txq = &sc->sc_txq[txprio];
	volatile struct gt_eth_desc * const txd = &txq->txq_descs[txq->txq_lo];
	uint32_t intrmask = sc->sc_intrmask;
	size_t buflen;
	struct mbuf *m;

	GE_FUNC_ENTER(sc, "gfe_tx_enqueue");

	/*
	 * Anything in the pending queue to enqueue?  if not, punt. Likewise
	 * if the txq is not yet created.
	 * otherwise grab its dmamap.
	 */
	if (txq == NULL || (m = txq->txq_pendq.ifq_head) == NULL) {
		GE_FUNC_EXIT(sc, "-");
		return 0;
	}

	/*
	 * Have we [over]consumed our limit of descriptors?
	 * Do we have enough free descriptors?
	 */
	if (GE_TXDESC_MAX == txq->txq_nactive + 2) {
		volatile struct gt_eth_desc * const txd2 = &txq->txq_descs[txq->txq_fi];
		uint32_t cmdsts;
		size_t pktlen;
		GE_TXDPOSTSYNC(sc, txq, txq->txq_fi);
		cmdsts = gt32toh(txd2->ed_cmdsts);
		if (cmdsts & TX_CMD_O) {
			int nextin;
			/*
			 * Sometime the Discovery forgets to update the
			 * last descriptor.  See if we own the descriptor
			 * after it (since we know we've turned that to
			 * the discovery and if we owned it, the Discovery
			 * gave it back).  If we do, we know the Discovery
			 * gave back this one but forgot to mark it as ours.
			 */
			nextin = txq->txq_fi + 1;
			if (nextin == GE_TXDESC_MAX)
				nextin = 0;
			GE_TXDPOSTSYNC(sc, txq, nextin);
			if (gt32toh(txq->txq_descs[nextin].ed_cmdsts) & TX_CMD_O) {
				GE_TXDPRESYNC(sc, txq, txq->txq_fi);
				GE_TXDPRESYNC(sc, txq, nextin);
				GE_FUNC_EXIT(sc, "@");
				return 0;
			}
#ifdef DEBUG
			printf("%s: txenqueue: transmitter resynced at %d\n",
			    sc->sc_dev.dv_xname, txq->txq_fi);
#endif
		}
		if (++txq->txq_fi == GE_TXDESC_MAX)
			txq->txq_fi = 0;
		txq->txq_inptr = gt32toh(txd2->ed_bufptr) - txq->txq_buf_busaddr;
		pktlen = (gt32toh(txd2->ed_lencnt) >> 16) & 0xffff;
		txq->txq_inptr += roundup(pktlen, dcache_line_size);
		txq->txq_nactive--;

		/* statistics */
		ifp->if_opackets++;
		if (cmdsts & TX_STS_ES)
			ifp->if_oerrors++;
		GE_DPRINTF(sc, ("%%"));
	}

	buflen = roundup(m->m_pkthdr.len, dcache_line_size);

	/*
	 * If this packet would wrap around the end of the buffer, reset back
	 * to the beginning.
	 */
	if (txq->txq_outptr + buflen > GE_TXBUF_SIZE) {
		txq->txq_ei_gapcount += GE_TXBUF_SIZE - txq->txq_outptr;
		txq->txq_outptr = 0;
	}

	/*
	 * Make sure the output packet doesn't run over the beginning of
	 * what we've already given the GT.
	 */
	if (txq->txq_nactive > 0 && txq->txq_outptr <= txq->txq_inptr &&
	    txq->txq_outptr + buflen > txq->txq_inptr) {
		intrmask |= txq->txq_intrbits &
		    (ETH_IR_TxBufferHigh|ETH_IR_TxBufferLow);
		if (sc->sc_intrmask != intrmask) {
			sc->sc_intrmask = intrmask;
			GE_WRITE(sc, EIMR, sc->sc_intrmask);
		}
		GE_FUNC_EXIT(sc, "#");
		return 0;
	}

	/*
	 * The end-of-list descriptor we put on last time is the starting point
	 * for this packet.  The GT is supposed to terminate list processing on
	 * a NULL nxtptr but that currently is broken so a CPU-owned descriptor
	 * must terminate the list.
	 */
	intrmask = sc->sc_intrmask;

	m_copydata(m, 0, m->m_pkthdr.len,
	    (char *)txq->txq_buf_mem.gdm_kva + (int)txq->txq_outptr);
	bus_dmamap_sync(sc->sc_dmat, txq->txq_buf_mem.gdm_map,
	    txq->txq_outptr, buflen, BUS_DMASYNC_PREWRITE);
	txd->ed_bufptr = htogt32(txq->txq_buf_busaddr + txq->txq_outptr);
	txd->ed_lencnt = htogt32(m->m_pkthdr.len << 16);
	GE_TXDPRESYNC(sc, txq, txq->txq_lo);

	/*
	 * Request a buffer interrupt every 2/3 of the way thru the transmit
	 * buffer.
	 */
	txq->txq_ei_gapcount += buflen;
	if (txq->txq_ei_gapcount > 2 * GE_TXBUF_SIZE / 3) {
		txd->ed_cmdsts = htogt32(TX_CMD_FIRST|TX_CMD_LAST|TX_CMD_EI);
		txq->txq_ei_gapcount = 0;
	} else {
		txd->ed_cmdsts = htogt32(TX_CMD_FIRST|TX_CMD_LAST);
	}
#if 0
	GE_DPRINTF(sc, ("([%d]->%08lx.%08lx.%08lx.%08lx)", txq->txq_lo,
	    ((unsigned long *)txd)[0], ((unsigned long *)txd)[1],
	    ((unsigned long *)txd)[2], ((unsigned long *)txd)[3]));
#endif
	GE_TXDPRESYNC(sc, txq, txq->txq_lo);

	txq->txq_outptr += buflen;
	/*
	 * Tell the SDMA engine to "Fetch!"
	 */
	GE_WRITE(sc, ESDCMR,
		 txq->txq_esdcmrbits & (ETH_ESDCMR_TXDH|ETH_ESDCMR_TXDL));

	GE_DPRINTF(sc, ("(%d)", txq->txq_lo));

	/*
	 * Update the last out appropriately.
	 */
	txq->txq_nactive++;
	if (++txq->txq_lo == GE_TXDESC_MAX)
		txq->txq_lo = 0;

	/*
	 * Move mbuf from the pending queue to the snd queue.
	 */
	IF_DEQUEUE(&txq->txq_pendq, m);
#if NBPFILTER > 0
	if (ifp->if_bpf != NULL)
		bpf_mtap(ifp->if_bpf, m);
#endif
	m_freem(m);
	ifp->if_flags &= ~IFF_OACTIVE;

	/*
	 * Since we have put an item into the packet queue, we now want
	 * an interrupt when the transmit queue finishes processing the
	 * list.  But only update the mask if needs changing.
	 */
	intrmask |= txq->txq_intrbits & (ETH_IR_TxEndHigh|ETH_IR_TxEndLow);
	if (sc->sc_intrmask != intrmask) {
		sc->sc_intrmask = intrmask;
		GE_WRITE(sc, EIMR, sc->sc_intrmask);
	}
	if (ifp->if_timer == 0)
		ifp->if_timer = 5;
	GE_FUNC_EXIT(sc, "*");
	return 1;
}

uint32_t
gfe_tx_done(struct gfe_softc *sc, enum gfe_txprio txprio, uint32_t intrmask)
{
	struct gfe_txqueue * const txq = &sc->sc_txq[txprio];
	struct ifnet * const ifp = &sc->sc_ec.ec_if;

	GE_FUNC_ENTER(sc, "gfe_tx_done");

	if (txq == NULL) {
		GE_FUNC_EXIT(sc, "");
		return intrmask;
	}

	while (txq->txq_nactive > 0) {
		const int dcache_line_size = curcpu()->ci_ci.dcache_line_size;
		volatile struct gt_eth_desc *txd = &txq->txq_descs[txq->txq_fi];
		uint32_t cmdsts;
		size_t pktlen;

		GE_TXDPOSTSYNC(sc, txq, txq->txq_fi);
		if ((cmdsts = gt32toh(txd->ed_cmdsts)) & TX_CMD_O) {
			int nextin;

			if (txq->txq_nactive == 1) {
				GE_TXDPRESYNC(sc, txq, txq->txq_fi);
				GE_FUNC_EXIT(sc, "");
				return intrmask;
			}
			/*
			 * Sometimes the Discovery forgets to update the
			 * ownership bit in the descriptor.  See if we own the
			 * descriptor after it (since we know we've turned
			 * that to the Discovery and if we own it now then the
			 * Discovery gave it back).  If we do, we know the
			 * Discovery gave back this one but forgot to mark it
			 * as ours.
			 */
			nextin = txq->txq_fi + 1;
			if (nextin == GE_TXDESC_MAX)
				nextin = 0;
			GE_TXDPOSTSYNC(sc, txq, nextin);
			if (gt32toh(txq->txq_descs[nextin].ed_cmdsts) & TX_CMD_O) {
				GE_TXDPRESYNC(sc, txq, txq->txq_fi);
				GE_TXDPRESYNC(sc, txq, nextin);
				GE_FUNC_EXIT(sc, "");
				return intrmask;
			}
#ifdef DEBUG
			printf("%s: txdone: transmitter resynced at %d\n",
			    sc->sc_dev.dv_xname, txq->txq_fi);
#endif
		}
#if 0
		GE_DPRINTF(sc, ("([%d]<-%08lx.%08lx.%08lx.%08lx)",
		    txq->txq_lo,
		    ((unsigned long *)txd)[0], ((unsigned long *)txd)[1],
		    ((unsigned long *)txd)[2], ((unsigned long *)txd)[3]));
#endif
		GE_DPRINTF(sc, ("(%d)", txq->txq_fi));
		if (++txq->txq_fi == GE_TXDESC_MAX)
			txq->txq_fi = 0;
		txq->txq_inptr = gt32toh(txd->ed_bufptr) - txq->txq_buf_busaddr;
		pktlen = (gt32toh(txd->ed_lencnt) >> 16) & 0xffff;
		bus_dmamap_sync(sc->sc_dmat, txq->txq_buf_mem.gdm_map,
		    txq->txq_inptr, pktlen, BUS_DMASYNC_POSTWRITE);
		txq->txq_inptr += roundup(pktlen, dcache_line_size);

		/* statistics */
		ifp->if_opackets++;
		if (cmdsts & TX_STS_ES)
			ifp->if_oerrors++;

		/* txd->ed_bufptr = 0; */

		ifp->if_timer = 5;
		--txq->txq_nactive;
	}
	if (txq->txq_nactive != 0)
		panic("%s: transmit fifo%d empty but active count (%d) > 0!",
		    sc->sc_dev.dv_xname, txprio, txq->txq_nactive);
	ifp->if_timer = 0;
	intrmask &= ~(txq->txq_intrbits & (ETH_IR_TxEndHigh|ETH_IR_TxEndLow));
	intrmask &= ~(txq->txq_intrbits & (ETH_IR_TxBufferHigh|ETH_IR_TxBufferLow));
	GE_FUNC_EXIT(sc, "");
	return intrmask;
}

int
gfe_tx_txqalloc(struct gfe_softc *sc, enum gfe_txprio txprio)
{
	struct gfe_txqueue * const txq = &sc->sc_txq[txprio];
	int error;

	GE_FUNC_ENTER(sc, "gfe_tx_txqalloc");

	error = gfe_dmamem_alloc(sc, &txq->txq_desc_mem, 1,
	    GE_TXDESC_MEMSIZE, BUS_DMA_NOCACHE);
	if (error) {
		GE_FUNC_EXIT(sc, "");
		return error;
	}
	error = gfe_dmamem_alloc(sc, &txq->txq_buf_mem, 1, GE_TXBUF_SIZE, 0);
	if (error) {
		gfe_dmamem_free(sc, &txq->txq_desc_mem);
		GE_FUNC_EXIT(sc, "");
		return error;
	}
	GE_FUNC_EXIT(sc, "");
	return 0;
}

int
gfe_tx_start(struct gfe_softc *sc, enum gfe_txprio txprio)
{
	struct gfe_txqueue * const txq = &sc->sc_txq[txprio];
	volatile struct gt_eth_desc *txd;
	unsigned int i;
	bus_addr_t addr;

	GE_FUNC_ENTER(sc, "gfe_tx_start");

	sc->sc_intrmask &= ~(ETH_IR_TxEndHigh|ETH_IR_TxBufferHigh|
			     ETH_IR_TxEndLow |ETH_IR_TxBufferLow);

	if (sc->sc_flags & GE_NOFREE) {
		KASSERT(txq->txq_desc_mem.gdm_kva != NULL);
		KASSERT(txq->txq_buf_mem.gdm_kva != NULL);
	} else {
		int error = gfe_tx_txqalloc(sc, txprio);
		if (error) {
			GE_FUNC_EXIT(sc, "!");
			return error;
		}
	}

	txq->txq_descs =
	    (volatile struct gt_eth_desc *) txq->txq_desc_mem.gdm_kva;
	txq->txq_desc_busaddr = txq->txq_desc_mem.gdm_map->dm_segs[0].ds_addr;
	txq->txq_buf_busaddr = txq->txq_buf_mem.gdm_map->dm_segs[0].ds_addr;

	txq->txq_pendq.ifq_maxlen = 10;
	txq->txq_ei_gapcount = 0;
	txq->txq_nactive = 0;
	txq->txq_fi = 0;
	txq->txq_lo = 0;
	txq->txq_inptr = GE_TXBUF_SIZE;
	txq->txq_outptr = 0;
	for (i = 0, txd = txq->txq_descs,
	     addr = txq->txq_desc_busaddr + sizeof(*txd);
			i < GE_TXDESC_MAX - 1;
			i++, txd++, addr += sizeof(*txd)) {
		/*
		 * update the nxtptr to point to the next txd.
		 */
		txd->ed_cmdsts = 0;
		txd->ed_nxtptr = htogt32(addr);
	}
	txq->txq_descs[GE_TXDESC_MAX-1].ed_nxtptr =
	    htogt32(txq->txq_desc_busaddr);
	bus_dmamap_sync(sc->sc_dmat, txq->txq_desc_mem.gdm_map, 0,
	    GE_TXDESC_MEMSIZE, BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);

	switch (txprio) {
	case GE_TXPRIO_HI:
		txq->txq_intrbits = ETH_IR_TxEndHigh|ETH_IR_TxBufferHigh;
		txq->txq_esdcmrbits = ETH_ESDCMR_TXDH;
		txq->txq_epsrbits = ETH_EPSR_TxHigh;
		txq->txq_ectdp = ETH_ECTDP1(sc->sc_macno);
		GE_WRITE(sc, ECTDP1, txq->txq_desc_busaddr);
		break;

	case GE_TXPRIO_LO:
		txq->txq_intrbits = ETH_IR_TxEndLow|ETH_IR_TxBufferLow;
		txq->txq_esdcmrbits = ETH_ESDCMR_TXDL;
		txq->txq_epsrbits = ETH_EPSR_TxLow;
		txq->txq_ectdp = ETH_ECTDP0(sc->sc_macno);
		GE_WRITE(sc, ECTDP0, txq->txq_desc_busaddr);
		break;

	case GE_TXPRIO_NONE:
		break;
	}
#if 0
	GE_DPRINTF(sc, ("(ectdp=%#x", txq->txq_ectdp));
	gt_write(device_parent(&sc->sc_dev), txq->txq_ectdp,
	    txq->txq_desc_busaddr);
	GE_DPRINTF(sc, (")"));
#endif

	/*
	 * If we are restarting, there may be packets in the pending queue
	 * waiting to be enqueued.  Try enqueuing packets from both priority
	 * queues until the pending queue is empty or there no room for them
	 * on the device.
	 */
	while (gfe_tx_enqueue(sc, txprio))
		continue;

	GE_FUNC_EXIT(sc, "");
	return 0;
}

void
gfe_tx_cleanup(struct gfe_softc *sc, enum gfe_txprio txprio, int flush)
{
	struct gfe_txqueue * const txq = &sc->sc_txq[txprio];

	GE_FUNC_ENTER(sc, "gfe_tx_cleanup");
	if (txq == NULL) {
		GE_FUNC_EXIT(sc, "");
		return;
	}

	if (!flush) {
		GE_FUNC_EXIT(sc, "");
		return;
	}

	if ((sc->sc_flags & GE_NOFREE) == 0) {
		gfe_dmamem_free(sc, &txq->txq_desc_mem);
		gfe_dmamem_free(sc, &txq->txq_buf_mem);
	}
	GE_FUNC_EXIT(sc, "-F");
}

void
gfe_tx_stop(struct gfe_softc *sc, enum gfe_whack_op op)
{
	GE_FUNC_ENTER(sc, "gfe_tx_stop");

	GE_WRITE(sc, ESDCMR, ETH_ESDCMR_STDH|ETH_ESDCMR_STDL);

	sc->sc_intrmask = gfe_tx_done(sc, GE_TXPRIO_HI, sc->sc_intrmask);
	sc->sc_intrmask = gfe_tx_done(sc, GE_TXPRIO_LO, sc->sc_intrmask);
	sc->sc_intrmask &= ~(ETH_IR_TxEndHigh|ETH_IR_TxBufferHigh|
			     ETH_IR_TxEndLow |ETH_IR_TxBufferLow);

	gfe_tx_cleanup(sc, GE_TXPRIO_HI, op == GE_WHACK_STOP);
	gfe_tx_cleanup(sc, GE_TXPRIO_LO, op == GE_WHACK_STOP);

	sc->sc_ec.ec_if.if_timer = 0;
	GE_FUNC_EXIT(sc, "");
}

int
gfe_intr(void *arg)
{
	struct gfe_softc * const sc = arg;
	uint32_t cause;
	uint32_t intrmask = sc->sc_intrmask;
	int claim = 0;
	int cnt;

	GE_FUNC_ENTER(sc, "gfe_intr");

	for (cnt = 0; cnt < 4; cnt++) {
		if (sc->sc_intrmask != intrmask) {
			sc->sc_intrmask = intrmask;
			GE_WRITE(sc, EIMR, sc->sc_intrmask);
		}
		cause = GE_READ(sc, EICR);
		cause &= sc->sc_intrmask;
		GE_DPRINTF(sc, (".%#x", cause));
		if (cause == 0)
			break;

		claim = 1;

		GE_WRITE(sc, EICR, ~cause);
#ifndef GE_NORX
		if (cause & (ETH_IR_RxBuffer|ETH_IR_RxError))
			intrmask = gfe_rx_process(sc, cause, intrmask);
#endif

#ifndef GE_NOTX
		if (cause & (ETH_IR_TxBufferHigh|ETH_IR_TxEndHigh))
			intrmask = gfe_tx_done(sc, GE_TXPRIO_HI, intrmask);
		if (cause & (ETH_IR_TxBufferLow|ETH_IR_TxEndLow))
			intrmask = gfe_tx_done(sc, GE_TXPRIO_LO, intrmask);
#endif
		if (cause & ETH_IR_MIIPhySTC) {
			sc->sc_flags |= GE_PHYSTSCHG;
			/* intrmask &= ~ETH_IR_MIIPhySTC; */
		}
	}

	while (gfe_tx_enqueue(sc, GE_TXPRIO_HI))
		continue;
	while (gfe_tx_enqueue(sc, GE_TXPRIO_LO))
		continue;

	GE_FUNC_EXIT(sc, "");
	return claim;
}

int
gfe_mii_read (struct device *self, int phy, int reg)
{
	return gt_mii_read(self, device_parent(self), phy, reg);
}

void
gfe_mii_write (struct device *self, int phy, int reg, int value)
{
	gt_mii_write(self, device_parent(self), phy, reg, value);
}

void
gfe_mii_statchg (struct device *self)
{
	/* struct gfe_softc *sc = device_private(self); */
	/* do nothing? */
}

int
gfe_whack(struct gfe_softc *sc, enum gfe_whack_op op)
{
	int error = 0;
	GE_FUNC_ENTER(sc, "gfe_whack");

	switch (op) {
	case GE_WHACK_RESTART:
#ifndef GE_NOTX
		gfe_tx_stop(sc, op);
#endif
		/* sc->sc_ec.ec_if.if_flags &= ~IFF_RUNNING; */
		/* FALLTHROUGH */
	case GE_WHACK_START:
#ifndef GE_NOHASH
		if (error == 0 && sc->sc_hashtable == NULL) {
			error = gfe_hash_alloc(sc);
			if (error)
				break;
		}
		if (op != GE_WHACK_RESTART)
			gfe_hash_fill(sc);
#endif
#ifndef GE_NORX
		if (op != GE_WHACK_RESTART) {
			error = gfe_rx_prime(sc);
			if (error)
				break;
		}
#endif
#ifndef GE_NOTX
		error = gfe_tx_start(sc, GE_TXPRIO_HI);
		if (error)
			break;
#endif
		sc->sc_ec.ec_if.if_flags |= IFF_RUNNING;
		GE_WRITE(sc, EPCR, sc->sc_pcr | ETH_EPCR_EN);
		GE_WRITE(sc, EPCXR, sc->sc_pcxr);
		GE_WRITE(sc, EICR, 0);
		GE_WRITE(sc, EIMR, sc->sc_intrmask);
#ifndef GE_NOHASH
		GE_WRITE(sc, EHTPR, sc->sc_hash_mem.gdm_map->dm_segs->ds_addr);
#endif
#ifndef GE_NORX
		GE_WRITE(sc, ESDCMR, ETH_ESDCMR_ERD);
		sc->sc_flags |= GE_RXACTIVE;
#endif
		/* FALLTHROUGH */
	case GE_WHACK_CHANGE:
		GE_DPRINTF(sc, ("(pcr=%#x,imr=%#x)",
		    GE_READ(sc, EPCR), GE_READ(sc, EIMR)));
		GE_WRITE(sc, EPCR, sc->sc_pcr | ETH_EPCR_EN);
		GE_WRITE(sc, EIMR, sc->sc_intrmask);
		gfe_ifstart(&sc->sc_ec.ec_if);
		GE_DPRINTF(sc, ("(ectdp0=%#x, ectdp1=%#x)",
		    GE_READ(sc, ECTDP0), GE_READ(sc, ECTDP1)));
		GE_FUNC_EXIT(sc, "");
		return error;
	case GE_WHACK_STOP:
		break;
	}

#ifdef GE_DEBUG
	if (error)
		GE_DPRINTF(sc, (" failed: %d\n", error));
#endif
	GE_WRITE(sc, EPCR, sc->sc_pcr);
	GE_WRITE(sc, EIMR, 0);
	sc->sc_ec.ec_if.if_flags &= ~IFF_RUNNING;
#ifndef GE_NOTX
	gfe_tx_stop(sc, GE_WHACK_STOP);
#endif
#ifndef GE_NORX
	gfe_rx_stop(sc, GE_WHACK_STOP);
#endif
#ifndef GE_NOHASH
	if ((sc->sc_flags & GE_NOFREE) == 0) {
		gfe_dmamem_free(sc, &sc->sc_hash_mem);
		sc->sc_hashtable = NULL;
	}
#endif

	GE_FUNC_EXIT(sc, "");
	return error;
}

int
gfe_hash_compute(struct gfe_softc *sc, const uint8_t eaddr[ETHER_ADDR_LEN])
{
	uint32_t w0, add0, add1;
	uint32_t result;

	GE_FUNC_ENTER(sc, "gfe_hash_compute");
	add0 = ((uint32_t) eaddr[5] <<  0) |
	       ((uint32_t) eaddr[4] <<  8) |
	       ((uint32_t) eaddr[3] << 16);

	add0 = ((add0 & 0x00f0f0f0) >> 4) | ((add0 & 0x000f0f0f) << 4);
	add0 = ((add0 & 0x00cccccc) >> 2) | ((add0 & 0x00333333) << 2);
	add0 = ((add0 & 0x00aaaaaa) >> 1) | ((add0 & 0x00555555) << 1);

	add1 = ((uint32_t) eaddr[2] <<  0) |
	       ((uint32_t) eaddr[1] <<  8) |
	       ((uint32_t) eaddr[0] << 16);

	add1 = ((add1 & 0x00f0f0f0) >> 4) | ((add1 & 0x000f0f0f) << 4);
	add1 = ((add1 & 0x00cccccc) >> 2) | ((add1 & 0x00333333) << 2);
	add1 = ((add1 & 0x00aaaaaa) >> 1) | ((add1 & 0x00555555) << 1);

	GE_DPRINTF(sc, ("%s=", ether_sprintf(eaddr)));
	/*
	 * hashResult is the 15 bits Hash entry address.
	 * ethernetADD is a 48 bit number, which is derived from the Ethernet
	 *	MAC address, by nibble swapping in every byte (i.e MAC address
	 *	of 0x123456789abc translates to ethernetADD of 0x21436587a9cb).
	 */

	if ((sc->sc_pcr & ETH_EPCR_HM) == 0) {
		/*
		 * hashResult[14:0] = hashFunc0(ethernetADD[47:0])
		 *
		 * hashFunc0 calculates the hashResult in the following manner:
		 *   hashResult[ 8:0] = ethernetADD[14:8,1,0]
		 *		XOR ethernetADD[23:15] XOR ethernetADD[32:24]
		 */
		result = (add0 & 3) | ((add0 >> 6) & ~3);
		result ^= (add0 >> 15) ^ (add1 >>  0);
		result &= 0x1ff;
		/*
		 *   hashResult[14:9] = ethernetADD[7:2]
		 */
		result |= (add0 & ~3) << 7;	/* excess bits will be masked */
		GE_DPRINTF(sc, ("0(%#x)", result & 0x7fff));
	} else {
#define	TRIBITFLIP	073516240	/* yes its in octal */
		/*
		 * hashResult[14:0] = hashFunc1(ethernetADD[47:0])
		 *
		 * hashFunc1 calculates the hashResult in the following manner:
		 *   hashResult[08:00] = ethernetADD[06:14]
		 *		XOR ethernetADD[15:23] XOR ethernetADD[24:32]
		 */
		w0 = ((add0 >> 6) ^ (add0 >> 15) ^ (add1)) & 0x1ff;
		/*
		 * Now bitswap those 9 bits
		 */
		result = 0;
		result |= ((TRIBITFLIP >> (((w0 >> 0) & 7) * 3)) & 7) << 6;
		result |= ((TRIBITFLIP >> (((w0 >> 3) & 7) * 3)) & 7) << 3;
		result |= ((TRIBITFLIP >> (((w0 >> 6) & 7) * 3)) & 7) << 0;

		/*
		 *   hashResult[14:09] = ethernetADD[00:05]
		 */
		result |= ((TRIBITFLIP >> (((add0 >> 0) & 7) * 3)) & 7) << 12;
		result |= ((TRIBITFLIP >> (((add0 >> 3) & 7) * 3)) & 7) << 9;
		GE_DPRINTF(sc, ("1(%#x)", result));
	}
	GE_FUNC_EXIT(sc, "");
	return result & ((sc->sc_pcr & ETH_EPCR_HS_512) ? 0x7ff : 0x7fff);
}

int
gfe_hash_entry_op(struct gfe_softc *sc, enum gfe_hash_op op,
	enum gfe_rxprio prio, const uint8_t eaddr[ETHER_ADDR_LEN])
{
	uint64_t he;
	uint64_t *maybe_he_p = NULL;
	int limit;
	int hash;
	int maybe_hash = 0;

	GE_FUNC_ENTER(sc, "gfe_hash_entry_op");

	hash = gfe_hash_compute(sc, eaddr);

	if (sc->sc_hashtable == NULL) {
		panic("%s:%d: hashtable == NULL!", sc->sc_dev.dv_xname,
			__LINE__);
	}

	/*
	 * Assume we are going to insert so create the hash entry we
	 * are going to insert.  We also use it to match entries we
	 * will be removing.
	 */
	he = ((uint64_t) eaddr[5] << 43) |
	     ((uint64_t) eaddr[4] << 35) |
	     ((uint64_t) eaddr[3] << 27) |
	     ((uint64_t) eaddr[2] << 19) |
	     ((uint64_t) eaddr[1] << 11) |
	     ((uint64_t) eaddr[0] <<  3) |
	     HSH_PRIO_INS(prio) | HSH_V | HSH_R;

	/*
	 * The GT will search upto 12 entries for a hit, so we must mimic that.
	 */
	hash &= sc->sc_hashmask / sizeof(he);
	for (limit = HSH_LIMIT; limit > 0 ; --limit) {
		/*
		 * Does the GT wrap at the end, stop at the, or overrun the
		 * end?  Assume it wraps for now.  Stash a copy of the
		 * current hash entry.
		 */
		uint64_t *he_p = &sc->sc_hashtable[hash];
		uint64_t thishe = *he_p;

		/*
		 * If the hash entry isn't valid, that break the chain.  And
		 * this entry a good candidate for reuse.
		 */
		if ((thishe & HSH_V) == 0) {
			maybe_he_p = he_p;
			break;
		}

		/*
		 * If the hash entry has the same address we are looking for
		 * then ...  if we are removing and the skip bit is set, its
		 * already been removed.  if are adding and the skip bit is
		 * clear, then its already added.  In either return EBUSY
		 * indicating the op has already been done.  Otherwise flip
		 * the skip bit and return 0.
		 */
		if (((he ^ thishe) & HSH_ADDR_MASK) == 0) {
			if (((op == GE_HASH_REMOVE) && (thishe & HSH_S)) ||
			    ((op == GE_HASH_ADD) && (thishe & HSH_S) == 0))
				return EBUSY;
			*he_p = thishe ^ HSH_S;
			bus_dmamap_sync(sc->sc_dmat, sc->sc_hash_mem.gdm_map,
			    hash * sizeof(he), sizeof(he),
			    BUS_DMASYNC_PREWRITE);
			GE_FUNC_EXIT(sc, "^");
			return 0;
		}

		/*
		 * If we haven't found a slot for the entry and this entry
		 * is currently being skipped, return this entry.
		 */
		if (maybe_he_p == NULL && (thishe & HSH_S)) {
			maybe_he_p = he_p;
			maybe_hash = hash;
		}

		hash = (hash + 1) & (sc->sc_hashmask / sizeof(he));
	}

	/*
	 * If we got here, then there was no entry to remove.
	 */
	if (op == GE_HASH_REMOVE) {
		GE_FUNC_EXIT(sc, "?");
		return ENOENT;
	}

	/*
	 * If we couldn't find a slot, return an error.
	 */
	if (maybe_he_p == NULL) {
		GE_FUNC_EXIT(sc, "!");
		return ENOSPC;
	}

	/* Update the entry.
	 */
	*maybe_he_p = he;
	bus_dmamap_sync(sc->sc_dmat, sc->sc_hash_mem.gdm_map,
	    maybe_hash * sizeof(he), sizeof(he), BUS_DMASYNC_PREWRITE);
	GE_FUNC_EXIT(sc, "+");
	return 0;
}

int
gfe_hash_multichg(struct ethercom *ec, const struct ether_multi *enm, u_long cmd)
{
	struct gfe_softc * const sc = ec->ec_if.if_softc;
	int error;
	enum gfe_hash_op op;
	enum gfe_rxprio prio;

	GE_FUNC_ENTER(sc, "hash_multichg");
	/*
	 * Is this a wildcard entry?  If so and its being removed, recompute.
	 */
	if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN) != 0) {
		if (cmd == SIOCDELMULTI) {
			GE_FUNC_EXIT(sc, "");
			return ENETRESET;
		}

		/*
		 * Switch in
		 */
		sc->sc_flags |= GE_ALLMULTI;
		if ((sc->sc_pcr & ETH_EPCR_PM) == 0) {
			sc->sc_pcr |= ETH_EPCR_PM;
			GE_WRITE(sc, EPCR, sc->sc_pcr);
			GE_FUNC_EXIT(sc, "");
			return 0;
		}
		GE_FUNC_EXIT(sc, "");
		return ENETRESET;
	}

	prio = GE_RXPRIO_MEDLO;
	op = (cmd == SIOCDELMULTI ? GE_HASH_REMOVE : GE_HASH_ADD);

	if (sc->sc_hashtable == NULL) {
		GE_FUNC_EXIT(sc, "");
		return 0;
	}

	error = gfe_hash_entry_op(sc, op, prio, enm->enm_addrlo);
	if (error == EBUSY) {
		printf("%s: multichg: tried to %s %s again\n",
		       sc->sc_dev.dv_xname,
		       cmd == SIOCDELMULTI ? "remove" : "add",
		       ether_sprintf(enm->enm_addrlo));
		GE_FUNC_EXIT(sc, "");
		return 0;
	}

	if (error == ENOENT) {
		printf("%s: multichg: failed to remove %s: not in table\n",
		       sc->sc_dev.dv_xname,
		       ether_sprintf(enm->enm_addrlo));
		GE_FUNC_EXIT(sc, "");
		return 0;
	}

	if (error == ENOSPC) {
		printf("%s: multichg: failed to add %s: no space; regenerating table\n",
		       sc->sc_dev.dv_xname,
		       ether_sprintf(enm->enm_addrlo));
		GE_FUNC_EXIT(sc, "");
		return ENETRESET;
	}
	GE_DPRINTF(sc, ("%s: multichg: %s: %s succeeded\n",
	       sc->sc_dev.dv_xname,
	       cmd == SIOCDELMULTI ? "remove" : "add",
	       ether_sprintf(enm->enm_addrlo)));
	GE_FUNC_EXIT(sc, "");
	return 0;
}

int
gfe_hash_fill(struct gfe_softc *sc)
{
	struct ether_multistep step;
	struct ether_multi *enm;
	int error;

	GE_FUNC_ENTER(sc, "gfe_hash_fill");

	error = gfe_hash_entry_op(sc, GE_HASH_ADD, GE_RXPRIO_HI,
	    CLLADDR(sc->sc_ec.ec_if.if_sadl));
	if (error)
		GE_FUNC_EXIT(sc, "!");
		return error;

	sc->sc_flags &= ~GE_ALLMULTI;
	if ((sc->sc_ec.ec_if.if_flags & IFF_PROMISC) == 0)
		sc->sc_pcr &= ~ETH_EPCR_PM;
	ETHER_FIRST_MULTI(step, &sc->sc_ec, enm);
	while (enm != NULL) {
		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
			sc->sc_flags |= GE_ALLMULTI;
			sc->sc_pcr |= ETH_EPCR_PM;
		} else {
			error = gfe_hash_entry_op(sc, GE_HASH_ADD,
			    GE_RXPRIO_MEDLO, enm->enm_addrlo);
			if (error == ENOSPC)
				break;
		}
		ETHER_NEXT_MULTI(step, enm);
	}

	GE_FUNC_EXIT(sc, "");
	return error;
}

int
gfe_hash_alloc(struct gfe_softc *sc)
{
	int error;
	GE_FUNC_ENTER(sc, "gfe_hash_alloc");
	sc->sc_hashmask = (sc->sc_pcr & ETH_EPCR_HS_512 ? 16 : 256)*1024 - 1;
	error = gfe_dmamem_alloc(sc, &sc->sc_hash_mem, 1, sc->sc_hashmask + 1,
	    BUS_DMA_NOCACHE);
	if (error) {
		printf("%s: failed to allocate %d bytes for hash table: %d\n",
		    sc->sc_dev.dv_xname, sc->sc_hashmask + 1, error);
		GE_FUNC_EXIT(sc, "");
		return error;
	}
	sc->sc_hashtable = (uint64_t *) sc->sc_hash_mem.gdm_kva;
	memset(sc->sc_hashtable, 0, sc->sc_hashmask + 1);
	bus_dmamap_sync(sc->sc_dmat, sc->sc_hash_mem.gdm_map,
	    0, sc->sc_hashmask + 1, BUS_DMASYNC_PREWRITE);
	GE_FUNC_EXIT(sc, "");
	return 0;
}