xref: /freebsd/sys/dev/ipw/if_ipw.c (revision cbe2bd55ad7d0bd0ae26b0bd453ee9ba374d683a)

/*	$FreeBSD$	*/

/*-
 * Copyright (c) 2004-2006
 *      Damien Bergamini <damien.bergamini@free.fr>. 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 unmodified, 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>
__FBSDID("$FreeBSD$");

/*-
 * Intel(R) PRO/Wireless 2100 MiniPCI driver
 * http://www.intel.com/network/connectivity/products/wireless/prowireless_mobile.htm
 */

#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/sockio.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/queue.h>
#include <sys/taskqueue.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/linker.h>
#include <sys/firmware.h>

#include <machine/bus.h>
#include <machine/resource.h>
#include <sys/rman.h>

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

#include <net/bpf.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <net/ethernet.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_radiotap.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/if_ether.h>

#include <dev/ipw/if_ipwreg.h>
#include <dev/ipw/if_ipwvar.h>

#ifdef IPW_DEBUG
#define DPRINTF(x)	do { if (ipw_debug > 0) printf x; } while (0)
#define DPRINTFN(n, x)	do { if (ipw_debug >= (n)) printf x; } while (0)
int ipw_debug = 0;
SYSCTL_INT(_debug, OID_AUTO, ipw, CTLFLAG_RW, &ipw_debug, 0, "ipw debug level");
#else
#define DPRINTF(x)
#define DPRINTFN(n, x)
#endif

MODULE_DEPEND(ipw, pci,  1, 1, 1);
MODULE_DEPEND(ipw, wlan, 1, 1, 1);
MODULE_DEPEND(ipw, firmware, 1, 1, 1);

struct ipw_ident {
	uint16_t	vendor;
	uint16_t	device;
	const char	*name;
};

static const struct ipw_ident ipw_ident_table[] = {
	{ 0x8086, 0x1043, "Intel(R) PRO/Wireless 2100 MiniPCI" },

	{ 0, 0, NULL }
};

static int	ipw_dma_alloc(struct ipw_softc *);
static void	ipw_release(struct ipw_softc *);
static int	ipw_media_change(struct ifnet *);
static void	ipw_media_status(struct ifnet *, struct ifmediareq *);
static int	ipw_newstate(struct ieee80211com *, enum ieee80211_state, int);
static uint16_t	ipw_read_prom_word(struct ipw_softc *, uint8_t);
static void	ipw_command_intr(struct ipw_softc *, struct ipw_soft_buf *);
static void	ipw_newstate_intr(struct ipw_softc *, struct ipw_soft_buf *);
static void	ipw_data_intr(struct ipw_softc *, struct ipw_status *,
		    struct ipw_soft_bd *, struct ipw_soft_buf *);
static void	ipw_rx_intr(struct ipw_softc *);
static void	ipw_release_sbd(struct ipw_softc *, struct ipw_soft_bd *);
static void	ipw_tx_intr(struct ipw_softc *);
static void	ipw_intr(void *);
static void	ipw_dma_map_addr(void *, bus_dma_segment_t *, int, int);
static int	ipw_cmd(struct ipw_softc *, uint32_t, void *, uint32_t);
static int	ipw_tx_start(struct ifnet *, struct mbuf *,
		    struct ieee80211_node *);
static void	ipw_start(struct ifnet *);
static void	ipw_watchdog(struct ifnet *);
static int	ipw_ioctl(struct ifnet *, u_long, caddr_t);
static void	ipw_stop_master(struct ipw_softc *);
static int	ipw_reset(struct ipw_softc *);
static int	ipw_load_ucode(struct ipw_softc *, const char *, int);
static int	ipw_load_firmware(struct ipw_softc *, const char *, int);
static int	ipw_config(struct ipw_softc *);
static void	ipw_init_task(void *, int);
static void	ipw_init(void *);
static void	ipw_stop(void *);
static int	ipw_sysctl_stats(SYSCTL_HANDLER_ARGS);
static int	ipw_sysctl_radio(SYSCTL_HANDLER_ARGS);
static uint32_t	ipw_read_table1(struct ipw_softc *, uint32_t);
static void	ipw_write_table1(struct ipw_softc *, uint32_t, uint32_t);
static int	ipw_read_table2(struct ipw_softc *, uint32_t, void *,
		    uint32_t *);
static void	ipw_read_mem_1(struct ipw_softc *, bus_size_t, uint8_t *,
		    bus_size_t);
static void	ipw_write_mem_1(struct ipw_softc *, bus_size_t,
		    const uint8_t *, bus_size_t);

static int ipw_probe(device_t);
static int ipw_attach(device_t);
static int ipw_detach(device_t);
static int ipw_shutdown(device_t);
static int ipw_suspend(device_t);
static int ipw_resume(device_t);

static device_method_t ipw_methods[] = {
	/* Device interface */
	DEVMETHOD(device_probe,		ipw_probe),
	DEVMETHOD(device_attach,	ipw_attach),
	DEVMETHOD(device_detach,	ipw_detach),
	DEVMETHOD(device_shutdown,	ipw_shutdown),
	DEVMETHOD(device_suspend,	ipw_suspend),
	DEVMETHOD(device_resume,	ipw_resume),

	{ 0, 0 }
};

static driver_t ipw_driver = {
	"ipw",
	ipw_methods,
	sizeof (struct ipw_softc)
};

static devclass_t ipw_devclass;

DRIVER_MODULE(ipw, pci, ipw_driver, ipw_devclass, 0, 0);

/*
 * Supported rates for 802.11b mode (in 500Kbps unit).
 */
static const struct ieee80211_rateset ipw_rateset_11b =
	{ 4, { 2, 4, 11, 22 } };

static int
ipw_probe(device_t dev)
{
	const struct ipw_ident *ident;

	for (ident = ipw_ident_table; ident->name != NULL; ident++) {
		if (pci_get_vendor(dev) == ident->vendor &&
		    pci_get_device(dev) == ident->device) {
			device_set_desc(dev, ident->name);
			return 0;
		}
	}
	return ENXIO;
}

/* Base Address Register */
#define IPW_PCI_BAR0	0x10

static int
ipw_attach(device_t dev)
{
	struct ipw_softc *sc = device_get_softc(dev);
	struct ifnet *ifp;
	struct ieee80211com *ic = &sc->sc_ic;
	uint16_t val;
	int error, i;

	sc->sc_dev = dev;

	mtx_init(&sc->sc_mtx, device_get_nameunit(dev), MTX_NETWORK_LOCK,
	    MTX_DEF | MTX_RECURSE);

	TASK_INIT(&sc->sc_init_task, 0, ipw_init_task, sc);

	if (pci_get_powerstate(dev) != PCI_POWERSTATE_D0) {
		device_printf(dev, "chip is in D%d power mode "
		    "-- setting to D0\n", pci_get_powerstate(dev));
		pci_set_powerstate(dev, PCI_POWERSTATE_D0);
	}

	pci_write_config(dev, 0x41, 0, 1);

	/* enable bus-mastering */
	pci_enable_busmaster(dev);

	sc->mem_rid = IPW_PCI_BAR0;
	sc->mem = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->mem_rid,
	    RF_ACTIVE);
	if (sc->mem == NULL) {
		device_printf(dev, "could not allocate memory resource\n");
		goto fail;
	}

	sc->sc_st = rman_get_bustag(sc->mem);
	sc->sc_sh = rman_get_bushandle(sc->mem);

	sc->irq_rid = 0;
	sc->irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &sc->irq_rid,
	    RF_ACTIVE | RF_SHAREABLE);
	if (sc->irq == NULL) {
		device_printf(dev, "could not allocate interrupt resource\n");
		goto fail;
	}

	if (ipw_reset(sc) != 0) {
		device_printf(dev, "could not reset adapter\n");
		goto fail;
	}

	if (ipw_dma_alloc(sc) != 0) {
		device_printf(dev, "could not allocate DMA resources\n");
		goto fail;
	}

	ifp = sc->sc_ifp = if_alloc(IFT_ETHER);
	if (ifp == NULL) {
		device_printf(dev, "can not if_alloc()\n");
		goto fail;
	}

	ifp->if_softc = sc;
	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
	ifp->if_init = ipw_init;
	ifp->if_ioctl = ipw_ioctl;
	ifp->if_start = ipw_start;
	ifp->if_watchdog = ipw_watchdog;
	IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
	ifp->if_snd.ifq_drv_maxlen = IFQ_MAXLEN;
	IFQ_SET_READY(&ifp->if_snd);

	ic->ic_ifp = ifp;
	ic->ic_phytype = IEEE80211_T_DS;
	ic->ic_opmode = IEEE80211_M_STA;
	ic->ic_state = IEEE80211_S_INIT;

	/* set device capabilities */
	ic->ic_caps =
	    IEEE80211_C_IBSS |		/* IBSS mode supported */
	    IEEE80211_C_MONITOR |	/* monitor mode supported */
	    IEEE80211_C_TXPMGT |	/* tx power management */
	    IEEE80211_C_SHPREAMBLE;	/* short preamble supported */

	/* read MAC address from EEPROM */
	val = ipw_read_prom_word(sc, IPW_EEPROM_MAC + 0);
	ic->ic_myaddr[0] = val >> 8;
	ic->ic_myaddr[1] = val & 0xff;
	val = ipw_read_prom_word(sc, IPW_EEPROM_MAC + 1);
	ic->ic_myaddr[2] = val >> 8;
	ic->ic_myaddr[3] = val & 0xff;
	val = ipw_read_prom_word(sc, IPW_EEPROM_MAC + 2);
	ic->ic_myaddr[4] = val >> 8;
	ic->ic_myaddr[5] = val & 0xff;

	/* set supported .11b rates */
	ic->ic_sup_rates[IEEE80211_MODE_11B] = ipw_rateset_11b;

	/* set supported .11b channels */
	for (i = 1; i < 14; i++) {
		ic->ic_channels[i].ic_freq =
		    ieee80211_ieee2mhz(i, IEEE80211_CHAN_B);
		ic->ic_channels[i].ic_flags = IEEE80211_CHAN_B;
	}

	/* check support for radio transmitter switch in EEPROM */
	if (!(ipw_read_prom_word(sc, IPW_EEPROM_RADIO) & 8))
		sc->flags |= IPW_FLAG_HAS_RADIO_SWITCH;

	ieee80211_ifattach(ic);
	/* override state transition machine */
	sc->sc_newstate = ic->ic_newstate;
	ic->ic_newstate = ipw_newstate;
	ieee80211_media_init(ic, ipw_media_change, ipw_media_status);

	bpfattach2(ifp, DLT_IEEE802_11_RADIO,
	    sizeof (struct ieee80211_frame) + 64, &sc->sc_drvbpf);

	sc->sc_rxtap_len = sizeof sc->sc_rxtapu;
	sc->sc_rxtap.wr_ihdr.it_len = htole16(sc->sc_rxtap_len);
	sc->sc_rxtap.wr_ihdr.it_present = htole32(IPW_RX_RADIOTAP_PRESENT);

	sc->sc_txtap_len = sizeof sc->sc_txtapu;
	sc->sc_txtap.wt_ihdr.it_len = htole16(sc->sc_txtap_len);
	sc->sc_txtap.wt_ihdr.it_present = htole32(IPW_TX_RADIOTAP_PRESENT);

	/*
	 * Add a few sysctl knobs.
	 */
	sc->dwelltime = 100;

	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "radio",
	    CTLTYPE_INT | CTLFLAG_RD, sc, 0, ipw_sysctl_radio, "I",
	    "radio transmitter switch state (0=off, 1=on)");

	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "stats",
	    CTLTYPE_OPAQUE | CTLFLAG_RD, sc, 0, ipw_sysctl_stats, "S",
	    "statistics");

	SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO, "dwell",
	    CTLFLAG_RW, &sc->dwelltime, 0,
	    "channel dwell time (ms) for AP/station scanning");

	/*
	 * Hook our interrupt after all initialization is complete.
	 */
	error = bus_setup_intr(dev, sc->irq, INTR_TYPE_NET | INTR_MPSAFE,
	    ipw_intr, sc, &sc->sc_ih);
	if (error != 0) {
		device_printf(dev, "could not set up interrupt\n");
		goto fail;
	}

	if (bootverbose)
		ieee80211_announce(ic);

	return 0;

fail:	ipw_detach(dev);
	return ENXIO;
}

static int
ipw_detach(device_t dev)
{
	struct ipw_softc *sc = device_get_softc(dev);
	struct ieee80211com *ic = &sc->sc_ic;
	struct ifnet *ifp = ic->ic_ifp;

	ipw_stop(sc);

	if (ifp != NULL) {
		bpfdetach(ifp);
		ieee80211_ifdetach(ic);
	}

	ipw_release(sc);

	if (sc->irq != NULL) {
		bus_teardown_intr(dev, sc->irq, sc->sc_ih);
		bus_release_resource(dev, SYS_RES_IRQ, sc->irq_rid, sc->irq);
	}

	if (sc->mem != NULL)
		bus_release_resource(dev, SYS_RES_MEMORY, sc->mem_rid, sc->mem);

	if (ifp != NULL)
		if_free(ifp);

	if (sc->sc_firmware != NULL) {
		firmware_put(sc->sc_firmware, FIRMWARE_UNLOAD);
		sc->sc_firmware = NULL;
	}

	mtx_destroy(&sc->sc_mtx);

	return 0;
}

static int
ipw_dma_alloc(struct ipw_softc *sc)
{
	struct ipw_soft_bd *sbd;
	struct ipw_soft_hdr *shdr;
	struct ipw_soft_buf *sbuf;
	bus_addr_t physaddr;
	int error, i;

	/*
	 * Allocate and map tx ring.
	 */
	error = bus_dma_tag_create(NULL, 4, 0, BUS_SPACE_MAXADDR_32BIT,
	    BUS_SPACE_MAXADDR, NULL, NULL, IPW_TBD_SZ, 1, IPW_TBD_SZ, 0, NULL,
	    NULL, &sc->tbd_dmat);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not create tx ring DMA tag\n");
		goto fail;
	}

	error = bus_dmamem_alloc(sc->tbd_dmat, (void **)&sc->tbd_list,
	    BUS_DMA_NOWAIT | BUS_DMA_ZERO, &sc->tbd_map);
	if (error != 0) {
		device_printf(sc->sc_dev,
		    "could not allocate tx ring DMA memory\n");
		goto fail;
	}

	error = bus_dmamap_load(sc->tbd_dmat, sc->tbd_map, sc->tbd_list,
	    IPW_TBD_SZ, ipw_dma_map_addr, &sc->tbd_phys, 0);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not map tx ring DMA memory\n");
		goto fail;
	}

	/*
	 * Allocate and map rx ring.
	 */
	error = bus_dma_tag_create(NULL, 4, 0, BUS_SPACE_MAXADDR_32BIT,
	    BUS_SPACE_MAXADDR, NULL, NULL, IPW_RBD_SZ, 1, IPW_RBD_SZ, 0, NULL,
	    NULL, &sc->rbd_dmat);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not create rx ring DMA tag\n");
		goto fail;
	}

	error = bus_dmamem_alloc(sc->rbd_dmat, (void **)&sc->rbd_list,
	    BUS_DMA_NOWAIT | BUS_DMA_ZERO, &sc->rbd_map);
	if (error != 0) {
		device_printf(sc->sc_dev,
		    "could not allocate rx ring DMA memory\n");
		goto fail;
	}

	error = bus_dmamap_load(sc->rbd_dmat, sc->rbd_map, sc->rbd_list,
	    IPW_RBD_SZ, ipw_dma_map_addr, &sc->rbd_phys, 0);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not map rx ring DMA memory\n");
		goto fail;
	}

	/*
	 * Allocate and map status ring.
	 */
	error = bus_dma_tag_create(NULL, 4, 0, BUS_SPACE_MAXADDR_32BIT,
	    BUS_SPACE_MAXADDR, NULL, NULL, IPW_STATUS_SZ, 1, IPW_STATUS_SZ, 0,
	    NULL, NULL, &sc->status_dmat);
	if (error != 0) {
		device_printf(sc->sc_dev,
		    "could not create status ring DMA tag\n");
		goto fail;
	}

	error = bus_dmamem_alloc(sc->status_dmat, (void **)&sc->status_list,
	    BUS_DMA_NOWAIT | BUS_DMA_ZERO, &sc->status_map);
	if (error != 0) {
		device_printf(sc->sc_dev,
		    "could not allocate status ring DMA memory\n");
		goto fail;
	}

	error = bus_dmamap_load(sc->status_dmat, sc->status_map,
	    sc->status_list, IPW_STATUS_SZ, ipw_dma_map_addr, &sc->status_phys,
	    0);
	if (error != 0) {
		device_printf(sc->sc_dev,
		    "could not map status ring DMA memory\n");
		goto fail;
	}

	/*
	 * Allocate command DMA map.
	 */
	error = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
	    BUS_SPACE_MAXADDR, NULL, NULL, sizeof (struct ipw_cmd), 1,
	    sizeof (struct ipw_cmd), 0, NULL, NULL, &sc->cmd_dmat);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not create command DMA tag\n");
		goto fail;
	}

	error = bus_dmamap_create(sc->cmd_dmat, 0, &sc->cmd_map);
	if (error != 0) {
		device_printf(sc->sc_dev,
		    "could not create command DMA map\n");
		goto fail;
	}

	/*
	 * Allocate headers DMA maps.
	 */
	error = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
	    BUS_SPACE_MAXADDR, NULL, NULL, sizeof (struct ipw_hdr), 1,
	    sizeof (struct ipw_hdr), 0, NULL, NULL, &sc->hdr_dmat);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not create header DMA tag\n");
		goto fail;
	}

	SLIST_INIT(&sc->free_shdr);
	for (i = 0; i < IPW_NDATA; i++) {
		shdr = &sc->shdr_list[i];
		error = bus_dmamap_create(sc->hdr_dmat, 0, &shdr->map);
		if (error != 0) {
			device_printf(sc->sc_dev,
			    "could not create header DMA map\n");
			goto fail;
		}
		SLIST_INSERT_HEAD(&sc->free_shdr, shdr, next);
	}

	/*
	 * Allocate tx buffers DMA maps.
	 */
	error = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
	    BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, IPW_MAX_NSEG, MCLBYTES, 0,
	    NULL, NULL, &sc->txbuf_dmat);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not create tx DMA tag\n");
		goto fail;
	}

	SLIST_INIT(&sc->free_sbuf);
	for (i = 0; i < IPW_NDATA; i++) {
		sbuf = &sc->tx_sbuf_list[i];
		error = bus_dmamap_create(sc->txbuf_dmat, 0, &sbuf->map);
		if (error != 0) {
			device_printf(sc->sc_dev,
			    "could not create tx DMA map\n");
			goto fail;
		}
		SLIST_INSERT_HEAD(&sc->free_sbuf, sbuf, next);
	}

	/*
	 * Initialize tx ring.
	 */
	for (i = 0; i < IPW_NTBD; i++) {
		sbd = &sc->stbd_list[i];
		sbd->bd = &sc->tbd_list[i];
		sbd->type = IPW_SBD_TYPE_NOASSOC;
	}

	/*
	 * Pre-allocate rx buffers and DMA maps.
	 */
	error = bus_dma_tag_create(NULL, 1, 0, BUS_SPACE_MAXADDR_32BIT,
	    BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, 1, MCLBYTES, 0, NULL,
	    NULL, &sc->rxbuf_dmat);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not create rx DMA tag\n");
		goto fail;
	}

	for (i = 0; i < IPW_NRBD; i++) {
		sbd = &sc->srbd_list[i];
		sbuf = &sc->rx_sbuf_list[i];
		sbd->bd = &sc->rbd_list[i];

		sbuf->m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
		if (sbuf->m == NULL) {
			device_printf(sc->sc_dev,
			    "could not allocate rx mbuf\n");
			error = ENOMEM;
			goto fail;
		}

		error = bus_dmamap_create(sc->rxbuf_dmat, 0, &sbuf->map);
		if (error != 0) {
			device_printf(sc->sc_dev,
			    "could not create rx DMA map\n");
			goto fail;
		}

		error = bus_dmamap_load(sc->rxbuf_dmat, sbuf->map,
		    mtod(sbuf->m, void *), MCLBYTES, ipw_dma_map_addr,
		    &physaddr, 0);
		if (error != 0) {
			device_printf(sc->sc_dev,
			    "could not map rx DMA memory\n");
			goto fail;
		}

		sbd->type = IPW_SBD_TYPE_DATA;
		sbd->priv = sbuf;
		sbd->bd->physaddr = htole32(physaddr);
		sbd->bd->len = htole32(MCLBYTES);
	}

	bus_dmamap_sync(sc->rbd_dmat, sc->rbd_map, BUS_DMASYNC_PREWRITE);

	return 0;

fail:	ipw_release(sc);
	return error;
}

static void
ipw_release(struct ipw_softc *sc)
{
	struct ipw_soft_buf *sbuf;
	int i;

	if (sc->tbd_dmat != NULL) {
		if (sc->stbd_list != NULL) {
			bus_dmamap_unload(sc->tbd_dmat, sc->tbd_map);
			bus_dmamem_free(sc->tbd_dmat, sc->tbd_list,
			    sc->tbd_map);
		}
		bus_dma_tag_destroy(sc->tbd_dmat);
	}

	if (sc->rbd_dmat != NULL) {
		if (sc->rbd_list != NULL) {
			bus_dmamap_unload(sc->rbd_dmat, sc->rbd_map);
			bus_dmamem_free(sc->rbd_dmat, sc->rbd_list,
			    sc->rbd_map);
		}
		bus_dma_tag_destroy(sc->rbd_dmat);
	}

	if (sc->status_dmat != NULL) {
		if (sc->status_list != NULL) {
			bus_dmamap_unload(sc->status_dmat, sc->status_map);
			bus_dmamem_free(sc->status_dmat, sc->status_list,
			    sc->status_map);
		}
		bus_dma_tag_destroy(sc->status_dmat);
	}

	for (i = 0; i < IPW_NTBD; i++)
		ipw_release_sbd(sc, &sc->stbd_list[i]);

	if (sc->cmd_dmat != NULL) {
		bus_dmamap_destroy(sc->cmd_dmat, sc->cmd_map);
		bus_dma_tag_destroy(sc->cmd_dmat);
	}

	if (sc->hdr_dmat != NULL) {
		for (i = 0; i < IPW_NDATA; i++)
			bus_dmamap_destroy(sc->hdr_dmat, sc->shdr_list[i].map);
		bus_dma_tag_destroy(sc->hdr_dmat);
	}

	if (sc->txbuf_dmat != NULL) {
		for (i = 0; i < IPW_NDATA; i++) {
			bus_dmamap_destroy(sc->txbuf_dmat,
			    sc->tx_sbuf_list[i].map);
		}
		bus_dma_tag_destroy(sc->txbuf_dmat);
	}

	if (sc->rxbuf_dmat != NULL) {
		for (i = 0; i < IPW_NRBD; i++) {
			sbuf = &sc->rx_sbuf_list[i];
			if (sbuf->m != NULL) {
				bus_dmamap_sync(sc->rxbuf_dmat, sbuf->map,
				    BUS_DMASYNC_POSTREAD);
				bus_dmamap_unload(sc->rxbuf_dmat, sbuf->map);
				m_freem(sbuf->m);
			}
			bus_dmamap_destroy(sc->rxbuf_dmat, sbuf->map);
		}
		bus_dma_tag_destroy(sc->rxbuf_dmat);
	}
}

static int
ipw_shutdown(device_t dev)
{
	struct ipw_softc *sc = device_get_softc(dev);

	ipw_stop(sc);

	return 0;
}

static int
ipw_suspend(device_t dev)
{
	struct ipw_softc *sc = device_get_softc(dev);

	ipw_stop(sc);

	return 0;
}

static int
ipw_resume(device_t dev)
{
	struct ipw_softc *sc = device_get_softc(dev);
	struct ifnet *ifp = sc->sc_ic.ic_ifp;

	mtx_lock(&sc->sc_mtx);

	pci_write_config(dev, 0x41, 0, 1);

	if (ifp->if_flags & IFF_UP) {
		ifp->if_init(ifp->if_softc);
		if (ifp->if_drv_flags & IFF_DRV_RUNNING)
			ifp->if_start(ifp);
	}

	mtx_unlock(&sc->sc_mtx);

	return 0;
}

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

	mtx_lock(&sc->sc_mtx);

	error = ieee80211_media_change(ifp);
	if (error != ENETRESET) {
		mtx_unlock(&sc->sc_mtx);
		return error;
	}

	if ((ifp->if_flags & IFF_UP) && (ifp->if_drv_flags & IFF_DRV_RUNNING))
		ipw_init(sc);

	mtx_unlock(&sc->sc_mtx);

	return 0;
}

/*
 * The firmware automatically adapts the transmit speed. We report its current
 * value here.
 */
static void
ipw_media_status(struct ifnet *ifp, struct ifmediareq *imr)
{
#define N(a)	(sizeof (a) / sizeof (a[0]))
	struct ipw_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = &sc->sc_ic;
	static const struct {
		uint32_t	val;
		int		rate;
	} rates[] = {
		{ IPW_RATE_DS1,   2 },
		{ IPW_RATE_DS2,   4 },
		{ IPW_RATE_DS5,  11 },
		{ IPW_RATE_DS11, 22 },
	};
	uint32_t val;
	int rate, i;

	imr->ifm_status = IFM_AVALID;
	imr->ifm_active = IFM_IEEE80211;
	if (ic->ic_state == IEEE80211_S_RUN)
		imr->ifm_status |= IFM_ACTIVE;

	/* read current transmission rate from adapter */
	val = ipw_read_table1(sc, IPW_INFO_CURRENT_TX_RATE) & 0xf;

	/* convert ipw rate to 802.11 rate */
	for (i = 0; i < N(rates) && rates[i].val != val; i++);
	rate = (i < N(rates)) ? rates[i].rate : 0;

	imr->ifm_active |= IFM_IEEE80211_11B;
	imr->ifm_active |= ieee80211_rate2media(ic, rate, IEEE80211_MODE_11B);
	switch (ic->ic_opmode) {
	case IEEE80211_M_STA:
		break;

	case IEEE80211_M_IBSS:
		imr->ifm_active |= IFM_IEEE80211_IBSS;
		break;

	case IEEE80211_M_MONITOR:
		imr->ifm_active |= IFM_IEEE80211_MONITOR;
		break;

	case IEEE80211_M_AHDEMO:
	case IEEE80211_M_HOSTAP:
		/* should not get there */
		break;
	}
#undef N
}

static int
ipw_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
{
	struct ifnet *ifp = ic->ic_ifp;
	struct ipw_softc *sc = ifp->if_softc;
	struct ieee80211_node *ni;
	uint8_t macaddr[IEEE80211_ADDR_LEN];
	uint32_t len;

	switch (nstate) {
	case IEEE80211_S_RUN:
		DELAY(200); /* firmware needs a short delay here */

		len = IEEE80211_ADDR_LEN;
		ipw_read_table2(sc, IPW_INFO_CURRENT_BSSID, macaddr, &len);

		ni = ieee80211_find_node(&ic->ic_scan, macaddr);
		if (ni == NULL)
			break;

		ieee80211_ref_node(ni);
		ieee80211_sta_join(ic, ni);
		ieee80211_node_authorize(ni);

		if (ic->ic_opmode == IEEE80211_M_STA)
			ieee80211_notify_node_join(ic, ni, 1);
		break;

	case IEEE80211_S_INIT:
	case IEEE80211_S_SCAN:
	case IEEE80211_S_AUTH:
	case IEEE80211_S_ASSOC:
		break;
	}

	ic->ic_state = nstate;

	return 0;
}

/*
 * Read 16 bits at address 'addr' from the serial EEPROM.
 */
static uint16_t
ipw_read_prom_word(struct ipw_softc *sc, uint8_t addr)
{
	uint32_t tmp;
	uint16_t val;
	int n;

	/* clock C once before the first command */
	IPW_EEPROM_CTL(sc, 0);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S | IPW_EEPROM_C);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S);

	/* write start bit (1) */
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S | IPW_EEPROM_D);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S | IPW_EEPROM_D | IPW_EEPROM_C);

	/* write READ opcode (10) */
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S | IPW_EEPROM_D);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S | IPW_EEPROM_D | IPW_EEPROM_C);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S | IPW_EEPROM_C);

	/* write address A7-A0 */
	for (n = 7; n >= 0; n--) {
		IPW_EEPROM_CTL(sc, IPW_EEPROM_S |
		    (((addr >> n) & 1) << IPW_EEPROM_SHIFT_D));
		IPW_EEPROM_CTL(sc, IPW_EEPROM_S |
		    (((addr >> n) & 1) << IPW_EEPROM_SHIFT_D) | IPW_EEPROM_C);
	}

	IPW_EEPROM_CTL(sc, IPW_EEPROM_S);

	/* read data Q15-Q0 */
	val = 0;
	for (n = 15; n >= 0; n--) {
		IPW_EEPROM_CTL(sc, IPW_EEPROM_S | IPW_EEPROM_C);
		IPW_EEPROM_CTL(sc, IPW_EEPROM_S);
		tmp = MEM_READ_4(sc, IPW_MEM_EEPROM_CTL);
		val |= ((tmp & IPW_EEPROM_Q) >> IPW_EEPROM_SHIFT_Q) << n;
	}

	IPW_EEPROM_CTL(sc, 0);

	/* clear Chip Select and clock C */
	IPW_EEPROM_CTL(sc, IPW_EEPROM_S);
	IPW_EEPROM_CTL(sc, 0);
	IPW_EEPROM_CTL(sc, IPW_EEPROM_C);

	return le16toh(val);
}

static void
ipw_command_intr(struct ipw_softc *sc, struct ipw_soft_buf *sbuf)
{
	struct ipw_cmd *cmd;

	bus_dmamap_sync(sc->rxbuf_dmat, sbuf->map, BUS_DMASYNC_POSTREAD);

	cmd = mtod(sbuf->m, struct ipw_cmd *);

	DPRINTFN(2, ("cmd ack'ed (%u, %u, %u, %u, %u)\n", le32toh(cmd->type),
	    le32toh(cmd->subtype), le32toh(cmd->seq), le32toh(cmd->len),
	    le32toh(cmd->status)));

	wakeup(sc);
}

static void
ipw_newstate_intr(struct ipw_softc *sc, struct ipw_soft_buf *sbuf)
{
	struct ieee80211com *ic = &sc->sc_ic;
	uint32_t state;

	bus_dmamap_sync(sc->rxbuf_dmat, sbuf->map, BUS_DMASYNC_POSTREAD);

	state = le32toh(*mtod(sbuf->m, uint32_t *));

	DPRINTFN(2, ("entering state %u\n", state));

	switch (state) {
	case IPW_STATE_ASSOCIATED:
		ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
		break;

	case IPW_STATE_SCANNING:
		/* don't leave run state on background scan */
		if (ic->ic_state != IEEE80211_S_RUN)
			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);

		ic->ic_flags |= IEEE80211_F_SCAN;
		break;

	case IPW_STATE_SCAN_COMPLETE:
		ieee80211_notify_scan_done(ic);
		ic->ic_flags &= ~IEEE80211_F_SCAN;
		break;

	case IPW_STATE_ASSOCIATION_LOST:
		ieee80211_new_state(ic, IEEE80211_S_INIT, -1);
		break;

	case IPW_STATE_RADIO_DISABLED:
		ic->ic_ifp->if_flags &= ~IFF_UP;
		ipw_stop(sc);
		break;
	}
}

/*
 * XXX: Hack to set the current channel to the value advertised in beacons or
 * probe responses. Only used during AP detection.
 */
static void
ipw_fix_channel(struct ieee80211com *ic, struct mbuf *m)
{
	struct ieee80211_frame *wh;
	uint8_t subtype;
	uint8_t *frm, *efrm;

	wh = mtod(m, struct ieee80211_frame *);

	if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_MGT)
		return;

	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;

	if (subtype != IEEE80211_FC0_SUBTYPE_BEACON &&
	    subtype != IEEE80211_FC0_SUBTYPE_PROBE_RESP)
		return;

	frm = (uint8_t *)(wh + 1);
	efrm = mtod(m, uint8_t *) + m->m_len;

	frm += 12;	/* skip tstamp, bintval and capinfo fields */
	while (frm < efrm) {
		if (*frm == IEEE80211_ELEMID_DSPARMS)
#if IEEE80211_CHAN_MAX < 255
		if (frm[2] <= IEEE80211_CHAN_MAX)
#endif
			ic->ic_curchan = &ic->ic_channels[frm[2]];

		frm += frm[1] + 2;
	}
}

static void
ipw_data_intr(struct ipw_softc *sc, struct ipw_status *status,
    struct ipw_soft_bd *sbd, struct ipw_soft_buf *sbuf)
{
	struct ieee80211com *ic = &sc->sc_ic;
	struct ifnet *ifp = ic->ic_ifp;
	struct mbuf *mnew, *m;
	struct ieee80211_frame *wh;
	struct ieee80211_node *ni;
	bus_addr_t physaddr;
	int error;

	DPRINTFN(5, ("received frame len=%u, rssi=%u\n", le32toh(status->len),
	    status->rssi));

	if (le32toh(status->len) < sizeof (struct ieee80211_frame_min) ||
	    le32toh(status->len) > MCLBYTES)
		return;

	/*
	 * Try to allocate a new mbuf for this ring element and load it before
	 * processing the current mbuf. If the ring element cannot be loaded,
	 * drop the received packet and reuse the old mbuf. In the unlikely
	 * case that the old mbuf can't be reloaded either, explicitly panic.
	 */
	mnew = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
	if (mnew == NULL) {
		ifp->if_ierrors++;
		return;
	}

	bus_dmamap_sync(sc->rxbuf_dmat, sbuf->map, BUS_DMASYNC_POSTREAD);
	bus_dmamap_unload(sc->rxbuf_dmat, sbuf->map);

	error = bus_dmamap_load(sc->rxbuf_dmat, sbuf->map, mtod(mnew, void *),
	    MCLBYTES, ipw_dma_map_addr, &physaddr, 0);
	if (error != 0) {
		m_freem(mnew);

		/* try to reload the old mbuf */
		error = bus_dmamap_load(sc->rxbuf_dmat, sbuf->map,
		    mtod(sbuf->m, void *), MCLBYTES, ipw_dma_map_addr,
		    &physaddr, 0);
		if (error != 0) {
			/* very unlikely that it will fail... */
			panic("%s: could not load old rx mbuf",
			    device_get_name(sc->sc_dev));
		}
		ifp->if_ierrors++;
		return;
	}

	/*
	 * New mbuf successfully loaded, update Rx ring and continue
	 * processing.
	 */
	m = sbuf->m;
	sbuf->m = mnew;
	sbd->bd->physaddr = htole32(physaddr);

	/* finalize mbuf */
	m->m_pkthdr.rcvif = ifp;
	m->m_pkthdr.len = m->m_len = le32toh(status->len);

	if (bpf_peers_present(sc->sc_drvbpf)) {
		struct ipw_rx_radiotap_header *tap = &sc->sc_rxtap;

		tap->wr_flags = 0;
		tap->wr_antsignal = status->rssi;
		tap->wr_chan_freq = htole16(ic->ic_curchan->ic_freq);
		tap->wr_chan_flags = htole16(ic->ic_curchan->ic_flags);

		bpf_mtap2(sc->sc_drvbpf, tap, sc->sc_rxtap_len, m);
	}

	if (ic->ic_state == IEEE80211_S_SCAN)
		ipw_fix_channel(ic, m);

	wh = mtod(m, struct ieee80211_frame *);
	ni = ieee80211_find_rxnode(ic, (struct ieee80211_frame_min *)wh);

	/* send the frame to the 802.11 layer */
	ieee80211_input(ic, m, ni, status->rssi, 0);

	/* node is no longer needed */
	ieee80211_free_node(ni);

	bus_dmamap_sync(sc->rbd_dmat, sc->rbd_map, BUS_DMASYNC_PREWRITE);
}

static void
ipw_rx_intr(struct ipw_softc *sc)
{
	struct ipw_status *status;
	struct ipw_soft_bd *sbd;
	struct ipw_soft_buf *sbuf;
	uint32_t r, i;

	if (!(sc->flags & IPW_FLAG_FW_INITED))
		return;

	r = CSR_READ_4(sc, IPW_CSR_RX_READ);

	bus_dmamap_sync(sc->status_dmat, sc->status_map, BUS_DMASYNC_POSTREAD);

	for (i = (sc->rxcur + 1) % IPW_NRBD; i != r; i = (i + 1) % IPW_NRBD) {
		status = &sc->status_list[i];
		sbd = &sc->srbd_list[i];
		sbuf = sbd->priv;

		switch (le16toh(status->code) & 0xf) {
		case IPW_STATUS_CODE_COMMAND:
			ipw_command_intr(sc, sbuf);
			break;

		case IPW_STATUS_CODE_NEWSTATE:
			ipw_newstate_intr(sc, sbuf);
			break;

		case IPW_STATUS_CODE_DATA_802_3:
		case IPW_STATUS_CODE_DATA_802_11:
			ipw_data_intr(sc, status, sbd, sbuf);
			break;

		case IPW_STATUS_CODE_NOTIFICATION:
			DPRINTFN(2, ("received notification\n"));
			break;

		default:
			device_printf(sc->sc_dev, "unknown status code %u\n",
			    le16toh(status->code));
		}

		/* firmware was killed, stop processing received frames */
		if (!(sc->flags & IPW_FLAG_FW_INITED))
			return;

		sbd->bd->flags = 0;
	}

	bus_dmamap_sync(sc->rbd_dmat, sc->rbd_map, BUS_DMASYNC_PREWRITE);

	/* kick the firmware */
	sc->rxcur = (r == 0) ? IPW_NRBD - 1 : r - 1;
	CSR_WRITE_4(sc, IPW_CSR_RX_WRITE, sc->rxcur);
}

static void
ipw_release_sbd(struct ipw_softc *sc, struct ipw_soft_bd *sbd)
{
	struct ipw_soft_hdr *shdr;
	struct ipw_soft_buf *sbuf;

	switch (sbd->type) {
	case IPW_SBD_TYPE_COMMAND:
		bus_dmamap_sync(sc->cmd_dmat, sc->cmd_map,
		    BUS_DMASYNC_POSTWRITE);
		bus_dmamap_unload(sc->cmd_dmat, sc->cmd_map);
		break;

	case IPW_SBD_TYPE_HEADER:
		shdr = sbd->priv;
		bus_dmamap_sync(sc->hdr_dmat, shdr->map, BUS_DMASYNC_POSTWRITE);
		bus_dmamap_unload(sc->hdr_dmat, shdr->map);
		SLIST_INSERT_HEAD(&sc->free_shdr, shdr, next);
		break;

	case IPW_SBD_TYPE_DATA:
		sbuf = sbd->priv;
		bus_dmamap_sync(sc->txbuf_dmat, sbuf->map,
		    BUS_DMASYNC_POSTWRITE);
		bus_dmamap_unload(sc->txbuf_dmat, sbuf->map);
		SLIST_INSERT_HEAD(&sc->free_sbuf, sbuf, next);

		m_freem(sbuf->m);
		ieee80211_free_node(sbuf->ni);

		sc->sc_tx_timer = 0;
		break;
	}

	sbd->type = IPW_SBD_TYPE_NOASSOC;
}

static void
ipw_tx_intr(struct ipw_softc *sc)
{
	struct ifnet *ifp = sc->sc_ic.ic_ifp;
	struct ipw_soft_bd *sbd;
	uint32_t r, i;

	if (!(sc->flags & IPW_FLAG_FW_INITED))
		return;

	r = CSR_READ_4(sc, IPW_CSR_TX_READ);

	for (i = (sc->txold + 1) % IPW_NTBD; i != r; i = (i + 1) % IPW_NTBD) {
		sbd = &sc->stbd_list[i];

		if (sbd->type == IPW_SBD_TYPE_DATA)
			ifp->if_opackets++;

		ipw_release_sbd(sc, sbd);
		sc->txfree++;
	}

	/* remember what the firmware has processed */
	sc->txold = (r == 0) ? IPW_NTBD - 1 : r - 1;

	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
	ipw_start(ifp);
}

static void
ipw_intr(void *arg)
{
	struct ipw_softc *sc = arg;
	uint32_t r;

	mtx_lock(&sc->sc_mtx);

	if ((r = CSR_READ_4(sc, IPW_CSR_INTR)) == 0 || r == 0xffffffff) {
		mtx_unlock(&sc->sc_mtx);
		return;
	}

	/* disable interrupts */
	CSR_WRITE_4(sc, IPW_CSR_INTR_MASK, 0);

	/* acknowledge all interrupts */
	CSR_WRITE_4(sc, IPW_CSR_INTR, r);

	if (r & (IPW_INTR_FATAL_ERROR | IPW_INTR_PARITY_ERROR)) {
		device_printf(sc->sc_dev, "firmware error\n");
		taskqueue_enqueue_fast(taskqueue_fast, &sc->sc_init_task);
		r = 0;	/* don't process more interrupts */
	}

	if (r & IPW_INTR_FW_INIT_DONE)
		wakeup(sc);

	if (r & IPW_INTR_RX_TRANSFER)
		ipw_rx_intr(sc);

	if (r & IPW_INTR_TX_TRANSFER)
		ipw_tx_intr(sc);

	/* re-enable interrupts */
	CSR_WRITE_4(sc, IPW_CSR_INTR_MASK, IPW_INTR_MASK);

	mtx_unlock(&sc->sc_mtx);
}

static void
ipw_dma_map_addr(void *arg, bus_dma_segment_t *segs, int nseg, int error)
{
	if (error != 0)
		return;

	KASSERT(nseg == 1, ("too many DMA segments, %d should be 1", nseg));

	*(bus_addr_t *)arg = segs[0].ds_addr;
}

/*
 * Send a command to the firmware and wait for the acknowledgement.
 */
static int
ipw_cmd(struct ipw_softc *sc, uint32_t type, void *data, uint32_t len)
{
	struct ipw_soft_bd *sbd;
	bus_addr_t physaddr;
	int error;

	sbd = &sc->stbd_list[sc->txcur];

	error = bus_dmamap_load(sc->cmd_dmat, sc->cmd_map, &sc->cmd,
	    sizeof (struct ipw_cmd), ipw_dma_map_addr, &physaddr, 0);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not map command DMA memory\n");
		return error;
	}

	sc->cmd.type = htole32(type);
	sc->cmd.subtype = 0;
	sc->cmd.len = htole32(len);
	sc->cmd.seq = 0;
	memcpy(sc->cmd.data, data, len);

	sbd->type = IPW_SBD_TYPE_COMMAND;
	sbd->bd->physaddr = htole32(physaddr);
	sbd->bd->len = htole32(sizeof (struct ipw_cmd));
	sbd->bd->nfrag = 1;
	sbd->bd->flags = IPW_BD_FLAG_TX_FRAME_COMMAND |
	    IPW_BD_FLAG_TX_LAST_FRAGMENT;

	bus_dmamap_sync(sc->cmd_dmat, sc->cmd_map, BUS_DMASYNC_PREWRITE);
	bus_dmamap_sync(sc->tbd_dmat, sc->tbd_map, BUS_DMASYNC_PREWRITE);

	DPRINTFN(2, ("sending command (%u, %u, %u, %u)\n", type, 0, 0, len));

	/* kick firmware */
	sc->txfree--;
	sc->txcur = (sc->txcur + 1) % IPW_NTBD;
	CSR_WRITE_4(sc, IPW_CSR_TX_WRITE, sc->txcur);

	/* wait at most one second for command to complete */
	return msleep(sc, &sc->sc_mtx, 0, "ipwcmd", hz);
}

static int
ipw_tx_start(struct ifnet *ifp, struct mbuf *m0, struct ieee80211_node *ni)
{
	struct ipw_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = &sc->sc_ic;
	struct ieee80211_frame *wh;
	struct ipw_soft_bd *sbd;
	struct ipw_soft_hdr *shdr;
	struct ipw_soft_buf *sbuf;
	struct ieee80211_key *k;
	struct mbuf *mnew;
	bus_dma_segment_t segs[IPW_MAX_NSEG];
	bus_addr_t physaddr;
	int nsegs, error, i;

	wh = mtod(m0, struct ieee80211_frame *);

	if (wh->i_fc[1] & IEEE80211_FC1_WEP) {
		k = ieee80211_crypto_encap(ic, ni, m0);
		if (k == NULL) {
			m_freem(m0);
			return ENOBUFS;
		}

		/* packet header may have moved, reset our local pointer */
		wh = mtod(m0, struct ieee80211_frame *);
	}

	if (bpf_peers_present(sc->sc_drvbpf)) {
		struct ipw_tx_radiotap_header *tap = &sc->sc_txtap;

		tap->wt_flags = 0;
		tap->wt_chan_freq = htole16(ic->ic_curchan->ic_freq);
		tap->wt_chan_flags = htole16(ic->ic_curchan->ic_flags);

		bpf_mtap2(sc->sc_drvbpf, tap, sc->sc_txtap_len, m0);
	}

	shdr = SLIST_FIRST(&sc->free_shdr);
	sbuf = SLIST_FIRST(&sc->free_sbuf);
	KASSERT(shdr != NULL && sbuf != NULL, ("empty sw hdr/buf pool"));

	shdr->hdr.type = htole32(IPW_HDR_TYPE_SEND);
	shdr->hdr.subtype = 0;
	shdr->hdr.encrypted = (wh->i_fc[1] & IEEE80211_FC1_WEP) ? 1 : 0;
	shdr->hdr.encrypt = 0;
	shdr->hdr.keyidx = 0;
	shdr->hdr.keysz = 0;
	shdr->hdr.fragmentsz = 0;
	IEEE80211_ADDR_COPY(shdr->hdr.src_addr, wh->i_addr2);
	if (ic->ic_opmode == IEEE80211_M_STA)
		IEEE80211_ADDR_COPY(shdr->hdr.dst_addr, wh->i_addr3);
	else
		IEEE80211_ADDR_COPY(shdr->hdr.dst_addr, wh->i_addr1);

	/* trim IEEE802.11 header */
	m_adj(m0, sizeof (struct ieee80211_frame));

	error = bus_dmamap_load_mbuf_sg(sc->txbuf_dmat, sbuf->map, m0, segs,
	    &nsegs, 0);
	if (error != 0 && error != EFBIG) {
		device_printf(sc->sc_dev, "could not map mbuf (error %d)\n",
		    error);
		m_freem(m0);
		return error;
	}
	if (error != 0) {
		mnew = m_defrag(m0, M_DONTWAIT);
		if (mnew == NULL) {
			device_printf(sc->sc_dev,
			    "could not defragment mbuf\n");
			m_freem(m0);
			return ENOBUFS;
		}
		m0 = mnew;

		error = bus_dmamap_load_mbuf_sg(sc->txbuf_dmat, sbuf->map, m0,
		    segs, &nsegs, 0);
		if (error != 0) {
			device_printf(sc->sc_dev,
			    "could not map mbuf (error %d)\n", error);
			m_freem(m0);
			return error;
		}
	}

	error = bus_dmamap_load(sc->hdr_dmat, shdr->map, &shdr->hdr,
	    sizeof (struct ipw_hdr), ipw_dma_map_addr, &physaddr, 0);
	if (error != 0) {
		device_printf(sc->sc_dev, "could not map header DMA memory\n");
		bus_dmamap_unload(sc->txbuf_dmat, sbuf->map);
		m_freem(m0);
		return error;
	}

	SLIST_REMOVE_HEAD(&sc->free_sbuf, next);
	SLIST_REMOVE_HEAD(&sc->free_shdr, next);

	sbd = &sc->stbd_list[sc->txcur];
	sbd->type = IPW_SBD_TYPE_HEADER;
	sbd->priv = shdr;
	sbd->bd->physaddr = htole32(physaddr);
	sbd->bd->len = htole32(sizeof (struct ipw_hdr));
	sbd->bd->nfrag = 1 + nsegs;
	sbd->bd->flags = IPW_BD_FLAG_TX_FRAME_802_3 |
	    IPW_BD_FLAG_TX_NOT_LAST_FRAGMENT;

	DPRINTFN(5, ("sending tx hdr (%u, %u, %u, %u, %6D, %6D)\n",
	    shdr->hdr.type, shdr->hdr.subtype, shdr->hdr.encrypted,
	    shdr->hdr.encrypt, shdr->hdr.src_addr, ":", shdr->hdr.dst_addr,
	    ":"));

	sc->txfree--;
	sc->txcur = (sc->txcur + 1) % IPW_NTBD;

	sbuf->m = m0;
	sbuf->ni = ni;

	for (i = 0; i < nsegs; i++) {
		sbd = &sc->stbd_list[sc->txcur];

		sbd->bd->physaddr = htole32(segs[i].ds_addr);
		sbd->bd->len = htole32(segs[i].ds_len);
		sbd->bd->nfrag = 0;
		sbd->bd->flags = IPW_BD_FLAG_TX_FRAME_802_3;
		if (i == nsegs - 1) {
			sbd->type = IPW_SBD_TYPE_DATA;
			sbd->priv = sbuf;
			sbd->bd->flags |= IPW_BD_FLAG_TX_LAST_FRAGMENT;
		} else {
			sbd->type = IPW_SBD_TYPE_NOASSOC;
			sbd->bd->flags |= IPW_BD_FLAG_TX_NOT_LAST_FRAGMENT;
		}

		DPRINTFN(5, ("sending fragment (%d, %d)\n", i, segs[i].ds_len));

		sc->txfree--;
		sc->txcur = (sc->txcur + 1) % IPW_NTBD;
	}

	bus_dmamap_sync(sc->hdr_dmat, shdr->map, BUS_DMASYNC_PREWRITE);
	bus_dmamap_sync(sc->txbuf_dmat, sbuf->map, BUS_DMASYNC_PREWRITE);
	bus_dmamap_sync(sc->tbd_dmat, sc->tbd_map, BUS_DMASYNC_PREWRITE);

	/* kick firmware */
	CSR_WRITE_4(sc, IPW_CSR_TX_WRITE, sc->txcur);

	return 0;
}

static void
ipw_start(struct ifnet *ifp)
{
	struct ipw_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = &sc->sc_ic;
	struct mbuf *m0;
	struct ether_header *eh;
	struct ieee80211_node *ni;

	mtx_lock(&sc->sc_mtx);

	if (ic->ic_state != IEEE80211_S_RUN) {
		mtx_unlock(&sc->sc_mtx);
		return;
	}

	for (;;) {
		IFQ_DRV_DEQUEUE(&ifp->if_snd, m0);
		if (m0 == NULL)
			break;

		if (sc->txfree < 1 + IPW_MAX_NSEG) {
			IFQ_DRV_PREPEND(&ifp->if_snd, m0);
			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
			break;
		}

		if (m0->m_len < sizeof (struct ether_header) &&
		    (m0 = m_pullup(m0, sizeof (struct ether_header))) == NULL)
			continue;

		eh = mtod(m0, struct ether_header *);
		ni = ieee80211_find_txnode(ic, eh->ether_dhost);
		if (ni == NULL) {
			m_freem(m0);
			continue;
		}
		BPF_MTAP(ifp, m0);

		m0 = ieee80211_encap(ic, m0, ni);
		if (m0 == NULL) {
			ieee80211_free_node(ni);
			continue;
		}

		if (bpf_peers_present(ic->ic_rawbpf))
			bpf_mtap(ic->ic_rawbpf, m0);

		if (ipw_tx_start(ifp, m0, ni) != 0) {
			ieee80211_free_node(ni);
			ifp->if_oerrors++;
			break;
		}

		/* start watchdog timer */
		sc->sc_tx_timer = 5;
		ifp->if_timer = 1;
	}

	mtx_unlock(&sc->sc_mtx);
}

static void
ipw_watchdog(struct ifnet *ifp)
{
	struct ipw_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = &sc->sc_ic;

	mtx_lock(&sc->sc_mtx);

	ifp->if_timer = 0;

	if (sc->sc_tx_timer > 0) {
		if (--sc->sc_tx_timer == 0) {
			if_printf(ifp, "device timeout\n");
			ifp->if_oerrors++;
			taskqueue_enqueue_fast(taskqueue_fast,
			    &sc->sc_init_task);
			mtx_unlock(&sc->sc_mtx);
			return;
		}
		ifp->if_timer = 1;
	}

	ieee80211_watchdog(ic);

	mtx_unlock(&sc->sc_mtx);
}

static int
ipw_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
	struct ipw_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = &sc->sc_ic;
	int error = 0;

	mtx_lock(&sc->sc_mtx);

	switch (cmd) {
	case SIOCSIFFLAGS:
		if (ifp->if_flags & IFF_UP) {
			if (!(ifp->if_drv_flags & IFF_DRV_RUNNING))
				ipw_init(sc);
		} else {
			if (ifp->if_drv_flags & IFF_DRV_RUNNING)
				ipw_stop(sc);
		}
		break;

	default:
		error = ieee80211_ioctl(ic, cmd, data);
	}

	if (error == ENETRESET) {
		if ((ifp->if_flags & IFF_UP) &&
		    (ifp->if_drv_flags & IFF_DRV_RUNNING))
			ipw_init(sc);
		error = 0;
	}

	mtx_unlock(&sc->sc_mtx);

	return error;
}

static void
ipw_stop_master(struct ipw_softc *sc)
{
	uint32_t tmp;
	int ntries;

	/* disable interrupts */
	CSR_WRITE_4(sc, IPW_CSR_INTR_MASK, 0);

	CSR_WRITE_4(sc, IPW_CSR_RST, IPW_RST_STOP_MASTER);
	for (ntries = 0; ntries < 50; ntries++) {
		if (CSR_READ_4(sc, IPW_CSR_RST) & IPW_RST_MASTER_DISABLED)
			break;
		DELAY(10);
	}
	if (ntries == 50)
		device_printf(sc->sc_dev, "timeout waiting for master\n");

	tmp = CSR_READ_4(sc, IPW_CSR_RST);
	CSR_WRITE_4(sc, IPW_CSR_RST, tmp | IPW_RST_PRINCETON_RESET);

	sc->flags &= ~IPW_FLAG_FW_INITED;
}

static int
ipw_reset(struct ipw_softc *sc)
{
	uint32_t tmp;
	int ntries;

	ipw_stop_master(sc);

	/* move adapter to D0 state */
	tmp = CSR_READ_4(sc, IPW_CSR_CTL);
	CSR_WRITE_4(sc, IPW_CSR_CTL, tmp | IPW_CTL_INIT);

	/* wait for clock stabilization */
	for (ntries = 0; ntries < 1000; ntries++) {
		if (CSR_READ_4(sc, IPW_CSR_CTL) & IPW_CTL_CLOCK_READY)
			break;
		DELAY(200);
	}
	if (ntries == 1000)
		return EIO;

	tmp =  CSR_READ_4(sc, IPW_CSR_RST);
	CSR_WRITE_4(sc, IPW_CSR_RST, tmp | IPW_RST_SW_RESET);

	DELAY(10);

	tmp = CSR_READ_4(sc, IPW_CSR_CTL);
	CSR_WRITE_4(sc, IPW_CSR_CTL, tmp | IPW_CTL_INIT);

	return 0;
}

/*
 * Upload the microcode to the device.
 */
static int
ipw_load_ucode(struct ipw_softc *sc, const char *uc, int size)
{
	int ntries;

	MEM_WRITE_4(sc, 0x3000e0, 0x80000000);
	CSR_WRITE_4(sc, IPW_CSR_RST, 0);

	MEM_WRITE_2(sc, 0x220000, 0x0703);
	MEM_WRITE_2(sc, 0x220000, 0x0707);

	MEM_WRITE_1(sc, 0x210014, 0x72);
	MEM_WRITE_1(sc, 0x210014, 0x72);

	MEM_WRITE_1(sc, 0x210000, 0x40);
	MEM_WRITE_1(sc, 0x210000, 0x00);
	MEM_WRITE_1(sc, 0x210000, 0x40);

	MEM_WRITE_MULTI_1(sc, 0x210010, uc, size);

	MEM_WRITE_1(sc, 0x210000, 0x00);
	MEM_WRITE_1(sc, 0x210000, 0x00);
	MEM_WRITE_1(sc, 0x210000, 0x80);

	MEM_WRITE_2(sc, 0x220000, 0x0703);
	MEM_WRITE_2(sc, 0x220000, 0x0707);

	MEM_WRITE_1(sc, 0x210014, 0x72);
	MEM_WRITE_1(sc, 0x210014, 0x72);

	MEM_WRITE_1(sc, 0x210000, 0x00);
	MEM_WRITE_1(sc, 0x210000, 0x80);

	for (ntries = 0; ntries < 10; ntries++) {
		if (MEM_READ_1(sc, 0x210000) & 1)
			break;
		DELAY(10);
	}
	if (ntries == 10) {
		device_printf(sc->sc_dev,
		    "timeout waiting for ucode to initialize\n");
		return EIO;
	}

	MEM_WRITE_4(sc, 0x3000e0, 0);

	return 0;
}

/* set of macros to handle unaligned little endian data in firmware image */
#define GETLE32(p) ((p)[0] | (p)[1] << 8 | (p)[2] << 16 | (p)[3] << 24)
#define GETLE16(p) ((p)[0] | (p)[1] << 8)
static int
ipw_load_firmware(struct ipw_softc *sc, const char *fw, int size)
{
	const uint8_t *p, *end;
	uint32_t tmp, dst;
	uint16_t len;
	int error;

	p = fw;
	end = fw + size;
	while (p < end) {
		dst = GETLE32(p); p += 4;
		len = GETLE16(p); p += 2;

		ipw_write_mem_1(sc, dst, p, len);
		p += len;
	}

	CSR_WRITE_4(sc, IPW_CSR_IO, IPW_IO_GPIO1_ENABLE | IPW_IO_GPIO3_MASK |
	    IPW_IO_LED_OFF);

	/* enable interrupts */
	CSR_WRITE_4(sc, IPW_CSR_INTR_MASK, IPW_INTR_MASK);

	/* kick the firmware */
	CSR_WRITE_4(sc, IPW_CSR_RST, 0);

	tmp = CSR_READ_4(sc, IPW_CSR_CTL);
	CSR_WRITE_4(sc, IPW_CSR_CTL, tmp | IPW_CTL_ALLOW_STANDBY);

	/* wait at most one second for firmware initialization to complete */
	if ((error = msleep(sc, &sc->sc_mtx, 0, "ipwinit", hz)) != 0) {
		device_printf(sc->sc_dev, "timeout waiting for firmware "
		    "initialization to complete\n");
		return error;
	}

	tmp = CSR_READ_4(sc, IPW_CSR_IO);
	CSR_WRITE_4(sc, IPW_CSR_IO, tmp | IPW_IO_GPIO1_MASK |
	    IPW_IO_GPIO3_MASK);

	return 0;
}

static int
ipw_config(struct ipw_softc *sc)
{
	struct ieee80211com *ic = &sc->sc_ic;
	struct ifnet *ifp = ic->ic_ifp;
	struct ipw_security security;
	struct ieee80211_key *k;
	struct ipw_wep_key wepkey;
	struct ipw_scan_options options;
	struct ipw_configuration config;
	uint32_t data;
	int error, i;

	switch (ic->ic_opmode) {
	case IEEE80211_M_STA:
	case IEEE80211_M_HOSTAP:
		data = htole32(IPW_MODE_BSS);
		break;
	case IEEE80211_M_IBSS:
	case IEEE80211_M_AHDEMO:
		data = htole32(IPW_MODE_IBSS);
		break;
	case IEEE80211_M_MONITOR:
		data = htole32(IPW_MODE_MONITOR);
		break;
	}
	DPRINTF(("Setting mode to %u\n", le32toh(data)));
	error = ipw_cmd(sc, IPW_CMD_SET_MODE, &data, sizeof data);
	if (error != 0)
		return error;

	if (ic->ic_opmode == IEEE80211_M_IBSS ||
	    ic->ic_opmode == IEEE80211_M_MONITOR) {
		data = htole32(ieee80211_chan2ieee(ic, ic->ic_curchan));
		DPRINTF(("Setting channel to %u\n", le32toh(data)));
		error = ipw_cmd(sc, IPW_CMD_SET_CHANNEL, &data, sizeof data);
		if (error != 0)
			return error;
	}

	if (ic->ic_opmode == IEEE80211_M_MONITOR) {
		DPRINTF(("Enabling adapter\n"));
		return ipw_cmd(sc, IPW_CMD_ENABLE, NULL, 0);
	}

	IEEE80211_ADDR_COPY(ic->ic_myaddr, IF_LLADDR(ifp));
	DPRINTF(("Setting MAC address to %6D\n", ic->ic_myaddr, ":"));
	error = ipw_cmd(sc, IPW_CMD_SET_MAC_ADDRESS, ic->ic_myaddr,
	    IEEE80211_ADDR_LEN);
	if (error != 0)
		return error;

	config.flags = htole32(IPW_CFG_BSS_MASK | IPW_CFG_IBSS_MASK |
	    IPW_CFG_PREAMBLE_AUTO | IPW_CFG_802_1x_ENABLE);
	if (ic->ic_opmode == IEEE80211_M_IBSS)
		config.flags |= htole32(IPW_CFG_IBSS_AUTO_START);
	if (ifp->if_flags & IFF_PROMISC)
		config.flags |= htole32(IPW_CFG_PROMISCUOUS);
	config.bss_chan = htole32(0x3fff); /* channels 1-14 */
	config.ibss_chan = htole32(0x7ff); /* channels 1-11 */
	DPRINTF(("Setting configuration to 0x%x\n", le32toh(config.flags)));
	error = ipw_cmd(sc, IPW_CMD_SET_CONFIGURATION, &config, sizeof config);
	if (error != 0)
		return error;

	data = htole32(0x3); /* 1, 2 */
	DPRINTF(("Setting basic tx rates to 0x%x\n", le32toh(data)));
	error = ipw_cmd(sc, IPW_CMD_SET_BASIC_TX_RATES, &data, sizeof data);
	if (error != 0)
		return error;

	data = htole32(0xf); /* 1, 2, 5.5, 11 */
	DPRINTF(("Setting tx rates to 0x%x\n", le32toh(data)));
	error = ipw_cmd(sc, IPW_CMD_SET_TX_RATES, &data, sizeof data);
	if (error != 0)
		return error;

	data = htole32(IPW_POWER_MODE_CAM);
	DPRINTF(("Setting power mode to %u\n", le32toh(data)));
	error = ipw_cmd(sc, IPW_CMD_SET_POWER_MODE, &data, sizeof data);
	if (error != 0)
		return error;

	if (ic->ic_opmode == IEEE80211_M_IBSS) {
		data = htole32(32); /* default value */
		DPRINTF(("Setting tx power index to %u\n", le32toh(data)));
		error = ipw_cmd(sc, IPW_CMD_SET_TX_POWER_INDEX, &data,
		    sizeof data);
		if (error != 0)
			return error;
	}

	data = htole32(ic->ic_rtsthreshold);
	DPRINTF(("Setting RTS threshold to %u\n", le32toh(data)));
	error = ipw_cmd(sc, IPW_CMD_SET_RTS_THRESHOLD, &data, sizeof data);
	if (error != 0)
		return error;

	data = htole32(ic->ic_fragthreshold);
	DPRINTF(("Setting frag threshold to %u\n", le32toh(data)));
	error = ipw_cmd(sc, IPW_CMD_SET_FRAG_THRESHOLD, &data, sizeof data);
	if (error != 0)
		return error;

#ifdef IPW_DEBUG
	if (ipw_debug > 0) {
		printf("Setting ESSID to ");
		ieee80211_print_essid(ic->ic_des_essid, ic->ic_des_esslen);
		printf("\n");
	}
#endif
	error = ipw_cmd(sc, IPW_CMD_SET_ESSID, ic->ic_des_essid,
	    ic->ic_des_esslen);
	if (error != 0)
		return error;

	/* no mandatory BSSID */
	DPRINTF(("Setting mandatory BSSID to null\n"));
	error = ipw_cmd(sc, IPW_CMD_SET_MANDATORY_BSSID, NULL, 0);
	if (error != 0)
		return error;

	if (ic->ic_flags & IEEE80211_F_DESBSSID) {
		DPRINTF(("Setting desired BSSID to %6D\n", ic->ic_des_bssid,
		    ":"));
		error = ipw_cmd(sc, IPW_CMD_SET_DESIRED_BSSID,
		    ic->ic_des_bssid, IEEE80211_ADDR_LEN);
		if (error != 0)
			return error;
	}

	memset(&security, 0, sizeof security);
	security.authmode = (ic->ic_bss->ni_authmode == IEEE80211_AUTH_SHARED) ?
	    IPW_AUTH_SHARED : IPW_AUTH_OPEN;
	security.ciphers = htole32(IPW_CIPHER_NONE);
	DPRINTF(("Setting authmode to %u\n", security.authmode));
	error = ipw_cmd(sc, IPW_CMD_SET_SECURITY_INFORMATION, &security,
	    sizeof security);
	if (error != 0)
		return error;

	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
		k = ic->ic_crypto.cs_nw_keys;
		for (i = 0; i < IEEE80211_WEP_NKID; i++, k++) {
			if (k->wk_keylen == 0)
				continue;

			wepkey.idx = i;
			wepkey.len = k->wk_keylen;
			memset(wepkey.key, 0, sizeof wepkey.key);
			memcpy(wepkey.key, k->wk_key, k->wk_keylen);
			DPRINTF(("Setting wep key index %u len %u\n",
			    wepkey.idx, wepkey.len));
			error = ipw_cmd(sc, IPW_CMD_SET_WEP_KEY, &wepkey,
			    sizeof wepkey);
			if (error != 0)
				return error;
		}

		data = htole32(ic->ic_crypto.cs_def_txkey);
		DPRINTF(("Setting wep tx key index to %u\n", le32toh(data)));
		error = ipw_cmd(sc, IPW_CMD_SET_WEP_KEY_INDEX, &data,
		    sizeof data);
		if (error != 0)
			return error;
	}

	data = htole32((ic->ic_flags & IEEE80211_F_PRIVACY) ? IPW_WEPON : 0);
	DPRINTF(("Setting wep flags to 0x%x\n", le32toh(data)));
	error = ipw_cmd(sc, IPW_CMD_SET_WEP_FLAGS, &data, sizeof data);
	if (error != 0)
		return error;

#if 0
	struct ipw_wpa_ie ie;

	memset(&ie, 0, sizeof ie);
	ie.len = htole32(sizeof (struct ieee80211_ie_wpa));
	DPRINTF(("Setting wpa ie\n"));
	error = ipw_cmd(sc, IPW_CMD_SET_WPA_IE, &ie, sizeof ie);
	if (error != 0)
		return error;
#endif

	if (ic->ic_opmode == IEEE80211_M_IBSS) {
		data = htole32(ic->ic_bintval);
		DPRINTF(("Setting beacon interval to %u\n", le32toh(data)));
		error = ipw_cmd(sc, IPW_CMD_SET_BEACON_INTERVAL, &data,
		    sizeof data);
		if (error != 0)
			return error;
	}

	options.flags = 0;
	options.channels = htole32(0x3fff); /* scan channels 1-14 */
	DPRINTF(("Setting scan options to 0x%x\n", le32toh(options.flags)));
	error = ipw_cmd(sc, IPW_CMD_SET_SCAN_OPTIONS, &options, sizeof options);
	if (error != 0)
		return error;

	/* finally, enable adapter (start scanning for an access point) */
	DPRINTF(("Enabling adapter\n"));
	return ipw_cmd(sc, IPW_CMD_ENABLE, NULL, 0);
}

/*
 * Handler for sc_init_task.  This is a simple wrapper around ipw_init().
 * It is called on firmware panics or on watchdog timeouts.
 */
static void
ipw_init_task(void *context, int pending)
{
	ipw_init(context);
}

static void
ipw_init(void *priv)
{
	struct ipw_softc *sc = priv;
	struct ieee80211com *ic = &sc->sc_ic;
	struct ifnet *ifp = ic->ic_ifp;
	struct firmware *fp;
	const struct ipw_firmware_hdr *hdr;
	const char *imagename, *fw;
	int owned;

	/*
	 * ipw_init() is exposed through ifp->if_init so it might be called
	 * without the driver's lock held.  Since msleep() doesn't like being
	 * called on a recursed mutex, we acquire the driver's lock only if
	 * we're not already holding it.
	 */
	if (!(owned = mtx_owned(&sc->sc_mtx)))
		mtx_lock(&sc->sc_mtx);

	/*
	 * Avoid re-entrant calls.  We need to release the mutex in ipw_init()
	 * when loading the firmware and we don't want to be called during this
	 * operation.
	 */
	if (sc->flags & IPW_FLAG_INIT_LOCKED) {
		if (!owned)
			mtx_unlock(&sc->sc_mtx);
		return;
	}
	sc->flags |= IPW_FLAG_INIT_LOCKED;

	ipw_stop(sc);

	if (ipw_reset(sc) != 0) {
		device_printf(sc->sc_dev, "could not reset adapter\n");
		goto fail1;
	}

	switch (ic->ic_opmode) {
	case IEEE80211_M_STA:
		imagename = "ipw_bss";
		break;
	case IEEE80211_M_IBSS:
		imagename = "ipw_ibss";
		break;
	case IEEE80211_M_MONITOR:
		imagename = "ipw_monitor";
		break;
	default:
		imagename = NULL;	/* should not get there */
	}

	/*
	 * Load firmware image using the firmware(9) subsystem.  We need to
	 * release the driver's lock first.
	 */
	if (sc->sc_firmware == NULL || strcmp(sc->sc_firmware->name,
	    imagename) != 0) {
		mtx_unlock(&sc->sc_mtx);
		if (sc->sc_firmware != NULL)
			firmware_put(sc->sc_firmware, FIRMWARE_UNLOAD);
		sc->sc_firmware = firmware_get(imagename);
		mtx_lock(&sc->sc_mtx);
	}

	if (sc->sc_firmware == NULL) {
		device_printf(sc->sc_dev,
		    "could not load firmware image '%s'\n", imagename);
		goto fail1;
	}

	fp = sc->sc_firmware;
	if (fp->datasize < sizeof *hdr) {
		device_printf(sc->sc_dev,
		    "firmware image too short %zu\n", fp->datasize);
		goto fail2;
	}

	hdr = (const struct ipw_firmware_hdr *)fp->data;

	if (fp->datasize < sizeof *hdr + le32toh(hdr->mainsz) +
	    le32toh(hdr->ucodesz)) {
		device_printf(sc->sc_dev,
		    "firmware image too short %zu\n", fp->datasize);
		goto fail2;
	}

	fw = (const char *)fp->data + sizeof *hdr + le32toh(hdr->mainsz);
	if (ipw_load_ucode(sc, fw, le32toh(hdr->ucodesz)) != 0) {
		device_printf(sc->sc_dev, "could not load microcode\n");
		goto fail2;
	}

	ipw_stop_master(sc);

	/*
	 * Setup tx, rx and status rings.
	 */
	sc->txold = IPW_NTBD - 1;
	sc->txcur = 0;
	sc->txfree = IPW_NTBD - 2;
	sc->rxcur = IPW_NRBD - 1;

	CSR_WRITE_4(sc, IPW_CSR_TX_BASE,  sc->tbd_phys);
	CSR_WRITE_4(sc, IPW_CSR_TX_SIZE,  IPW_NTBD);
	CSR_WRITE_4(sc, IPW_CSR_TX_READ,  0);
	CSR_WRITE_4(sc, IPW_CSR_TX_WRITE, sc->txcur);

	CSR_WRITE_4(sc, IPW_CSR_RX_BASE,  sc->rbd_phys);
	CSR_WRITE_4(sc, IPW_CSR_RX_SIZE,  IPW_NRBD);
	CSR_WRITE_4(sc, IPW_CSR_RX_READ,  0);
	CSR_WRITE_4(sc, IPW_CSR_RX_WRITE, sc->rxcur);

	CSR_WRITE_4(sc, IPW_CSR_STATUS_BASE, sc->status_phys);

	fw = (const char *)fp->data + sizeof *hdr;
	if (ipw_load_firmware(sc, fw, le32toh(hdr->mainsz)) != 0) {
		device_printf(sc->sc_dev, "could not load firmware\n");
		goto fail2;
	}

	sc->flags |= IPW_FLAG_FW_INITED;

	/* retrieve information tables base addresses */
	sc->table1_base = CSR_READ_4(sc, IPW_CSR_TABLE1_BASE);
	sc->table2_base = CSR_READ_4(sc, IPW_CSR_TABLE2_BASE);

	ipw_write_table1(sc, IPW_INFO_LOCK, 0);

	if (ipw_config(sc) != 0) {
		device_printf(sc->sc_dev, "device configuration failed\n");
		goto fail1;
	}

	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
	ifp->if_drv_flags |= IFF_DRV_RUNNING;

	sc->flags &=~ IPW_FLAG_INIT_LOCKED;

	if (!owned)
		mtx_unlock(&sc->sc_mtx);

	return;

fail2:	firmware_put(fp, FIRMWARE_UNLOAD);
	sc->sc_firmware = NULL;
fail1:	ifp->if_flags &= ~IFF_UP;
	ipw_stop(sc);
	sc->flags &=~ IPW_FLAG_INIT_LOCKED;
	if (!owned)
		mtx_unlock(&sc->sc_mtx);
}

static void
ipw_stop(void *priv)
{
	struct ipw_softc *sc = priv;
	struct ieee80211com *ic = &sc->sc_ic;
	struct ifnet *ifp = ic->ic_ifp;
	int i;

	mtx_lock(&sc->sc_mtx);

	ieee80211_new_state(ic, IEEE80211_S_INIT, -1);

	ipw_stop_master(sc);

	CSR_WRITE_4(sc, IPW_CSR_RST, IPW_RST_SW_RESET);

	/*
	 * Release tx buffers.
	 */
	for (i = 0; i < IPW_NTBD; i++)
		ipw_release_sbd(sc, &sc->stbd_list[i]);

	sc->sc_tx_timer = 0;
	ifp->if_timer = 0;
	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);

	mtx_unlock(&sc->sc_mtx);
}

static int
ipw_sysctl_stats(SYSCTL_HANDLER_ARGS)
{
	struct ipw_softc *sc = arg1;
	uint32_t i, size, buf[256];

	if (!(sc->flags & IPW_FLAG_FW_INITED)) {
		memset(buf, 0, sizeof buf);
		return SYSCTL_OUT(req, buf, sizeof buf);
	}

	CSR_WRITE_4(sc, IPW_CSR_AUTOINC_ADDR, sc->table1_base);

	size = min(CSR_READ_4(sc, IPW_CSR_AUTOINC_DATA), 256);
	for (i = 1; i < size; i++)
		buf[i] = MEM_READ_4(sc, CSR_READ_4(sc, IPW_CSR_AUTOINC_DATA));

	return SYSCTL_OUT(req, buf, sizeof buf);
}

static int
ipw_sysctl_radio(SYSCTL_HANDLER_ARGS)
{
	struct ipw_softc *sc = arg1;
	int val;

	val = !((sc->flags & IPW_FLAG_HAS_RADIO_SWITCH) &&
	        (CSR_READ_4(sc, IPW_CSR_IO) & IPW_IO_RADIO_DISABLED));

	return SYSCTL_OUT(req, &val, sizeof val);
}

static uint32_t
ipw_read_table1(struct ipw_softc *sc, uint32_t off)
{
	return MEM_READ_4(sc, MEM_READ_4(sc, sc->table1_base + off));
}

static void
ipw_write_table1(struct ipw_softc *sc, uint32_t off, uint32_t info)
{
	MEM_WRITE_4(sc, MEM_READ_4(sc, sc->table1_base + off), info);
}

static int
ipw_read_table2(struct ipw_softc *sc, uint32_t off, void *buf, uint32_t *len)
{
	uint32_t addr, info;
	uint16_t count, size;
	uint32_t total;

	/* addr[4] + count[2] + size[2] */
	addr = MEM_READ_4(sc, sc->table2_base + off);
	info = MEM_READ_4(sc, sc->table2_base + off + 4);

	count = info >> 16;
	size = info & 0xffff;
	total = count * size;

	if (total > *len) {
		*len = total;
		return EINVAL;
	}

	*len = total;
	ipw_read_mem_1(sc, addr, buf, total);

	return 0;
}

static void
ipw_read_mem_1(struct ipw_softc *sc, bus_size_t offset, uint8_t *datap,
    bus_size_t count)
{
	for (; count > 0; offset++, datap++, count--) {
		CSR_WRITE_4(sc, IPW_CSR_INDIRECT_ADDR, offset & ~3);
		*datap = CSR_READ_1(sc, IPW_CSR_INDIRECT_DATA + (offset & 3));
	}
}

static void
ipw_write_mem_1(struct ipw_softc *sc, bus_size_t offset, const uint8_t *datap,
    bus_size_t count)
{
	for (; count > 0; offset++, datap++, count--) {
		CSR_WRITE_4(sc, IPW_CSR_INDIRECT_ADDR, offset & ~3);
		CSR_WRITE_1(sc, IPW_CSR_INDIRECT_DATA + (offset & 3), *datap);
	}
}