root/sys/dev/pci/if_wpi.c
/*      $NetBSD: if_wpi.c,v 1.92 2021/12/05 07:08:08 msaitoh Exp $      */

/*-
 * Copyright (c) 2006, 2007
 *      Damien Bergamini <damien.bergamini@free.fr>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_wpi.c,v 1.92 2021/12/05 07:08:08 msaitoh Exp $");

/*
 * Driver for Intel PRO/Wireless 3945ABG 802.11 network adapters.
 */


#include <sys/param.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/once.h>
#include <sys/conf.h>
#include <sys/kauth.h>
#include <sys/callout.h>
#include <sys/proc.h>
#include <sys/kthread.h>

#include <sys/bus.h>
#include <machine/endian.h>
#include <sys/intr.h>

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

#include <dev/sysmon/sysmonvar.h>

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

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

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_amrr.h>
#include <net80211/ieee80211_radiotap.h>

#include <dev/firmload.h>

#include <dev/pci/if_wpireg.h>
#include <dev/pci/if_wpivar.h>

static const char wpi_firmware_name[] = "iwlwifi-3945.ucode";
static once_t wpi_firmware_init;
static kmutex_t wpi_firmware_mutex;
static size_t wpi_firmware_users;
static uint8_t *wpi_firmware_image;
static size_t wpi_firmware_size;

static int      wpi_match(device_t, cfdata_t, void *);
static void     wpi_attach(device_t, device_t, void *);
static int      wpi_detach(device_t , int);
static int      wpi_dma_contig_alloc(bus_dma_tag_t, struct wpi_dma_info *,
                    void **, bus_size_t, bus_size_t, int);
static void     wpi_dma_contig_free(struct wpi_dma_info *);
static int      wpi_alloc_shared(struct wpi_softc *);
static void     wpi_free_shared(struct wpi_softc *);
static int      wpi_alloc_fwmem(struct wpi_softc *);
static void     wpi_free_fwmem(struct wpi_softc *);
static struct   wpi_rbuf *wpi_alloc_rbuf(struct wpi_softc *);
static void     wpi_free_rbuf(struct mbuf *, void *, size_t, void *);
static int      wpi_alloc_rpool(struct wpi_softc *);
static void     wpi_free_rpool(struct wpi_softc *);
static int      wpi_alloc_rx_ring(struct wpi_softc *, struct wpi_rx_ring *);
static void     wpi_reset_rx_ring(struct wpi_softc *, struct wpi_rx_ring *);
static void     wpi_free_rx_ring(struct wpi_softc *, struct wpi_rx_ring *);
static int      wpi_alloc_tx_ring(struct wpi_softc *, struct wpi_tx_ring *,
                    int, int);
static void     wpi_reset_tx_ring(struct wpi_softc *, struct wpi_tx_ring *);
static void     wpi_free_tx_ring(struct wpi_softc *, struct wpi_tx_ring *);
static struct   ieee80211_node * wpi_node_alloc(struct ieee80211_node_table *);
static void     wpi_newassoc(struct ieee80211_node *, int);
static int      wpi_media_change(struct ifnet *);
static int      wpi_newstate(struct ieee80211com *, enum ieee80211_state, int);
static void     wpi_mem_lock(struct wpi_softc *);
static void     wpi_mem_unlock(struct wpi_softc *);
static uint32_t wpi_mem_read(struct wpi_softc *, uint16_t);
static void     wpi_mem_write(struct wpi_softc *, uint16_t, uint32_t);
static void     wpi_mem_write_region_4(struct wpi_softc *, uint16_t,
                    const uint32_t *, int);
static int      wpi_read_prom_data(struct wpi_softc *, uint32_t, void *, int);
static int      wpi_load_microcode(struct wpi_softc *,  const uint8_t *, int);
static int      wpi_cache_firmware(struct wpi_softc *);
static void     wpi_release_firmware(void);
static int      wpi_load_firmware(struct wpi_softc *);
static void     wpi_calib_timeout(void *);
static void     wpi_iter_func(void *, struct ieee80211_node *);
static void     wpi_power_calibration(struct wpi_softc *, int);
static void     wpi_rx_intr(struct wpi_softc *, struct wpi_rx_desc *,
                    struct wpi_rx_data *);
static void     wpi_tx_intr(struct wpi_softc *, struct wpi_rx_desc *);
static void     wpi_cmd_intr(struct wpi_softc *, struct wpi_rx_desc *);
static void     wpi_notif_intr(struct wpi_softc *);
static int      wpi_intr(void *);
static void     wpi_softintr(void *);
static void     wpi_read_eeprom(struct wpi_softc *);
static void     wpi_read_eeprom_channels(struct wpi_softc *, int);
static void     wpi_read_eeprom_group(struct wpi_softc *, int);
static uint8_t  wpi_plcp_signal(int);
static int      wpi_tx_data(struct wpi_softc *, struct mbuf *,
                    struct ieee80211_node *, int);
static void     wpi_start(struct ifnet *);
static void     wpi_watchdog(struct ifnet *);
static int      wpi_ioctl(struct ifnet *, u_long, void *);
static int      wpi_cmd(struct wpi_softc *, int, const void *, int, int);
static int      wpi_wme_update(struct ieee80211com *);
static int      wpi_mrr_setup(struct wpi_softc *);
static void     wpi_set_led(struct wpi_softc *, uint8_t, uint8_t, uint8_t);
static void     wpi_enable_tsf(struct wpi_softc *, struct ieee80211_node *);
static int      wpi_set_txpower(struct wpi_softc *,
                    struct ieee80211_channel *, int);
static int      wpi_get_power_index(struct wpi_softc *,
                    struct wpi_power_group *, struct ieee80211_channel *, int);
static int      wpi_setup_beacon(struct wpi_softc *, struct ieee80211_node *);
static int      wpi_auth(struct wpi_softc *);
static int      wpi_scan(struct wpi_softc *);
static int      wpi_config(struct wpi_softc *);
static void     wpi_stop_master(struct wpi_softc *);
static int      wpi_power_up(struct wpi_softc *);
static int      wpi_reset(struct wpi_softc *);
static void     wpi_hw_config(struct wpi_softc *);
static int      wpi_init(struct ifnet *);
static void     wpi_stop(struct ifnet *, int);
static bool     wpi_resume(device_t, const pmf_qual_t *);
static int      wpi_getrfkill(struct wpi_softc *);
static void     wpi_sysctlattach(struct wpi_softc *);
static void     wpi_rsw_thread(void *);
static void     wpi_rsw_suspend(struct wpi_softc *);
static void     wpi_stop_intr(struct ifnet *, int);

#ifdef WPI_DEBUG
#define DPRINTF(x)      do { if (wpi_debug > 0) printf x; } while (0)
#define DPRINTFN(n, x)  do { if (wpi_debug >= (n)) printf x; } while (0)
int wpi_debug = 1;
#else
#define DPRINTF(x)
#define DPRINTFN(n, x)
#endif

CFATTACH_DECL_NEW(wpi, sizeof (struct wpi_softc), wpi_match, wpi_attach,
        wpi_detach, NULL);

static int
wpi_match(device_t parent, cfdata_t match __unused, void *aux)
{
        struct pci_attach_args *pa = aux;

        if (PCI_VENDOR(pa->pa_id) != PCI_VENDOR_INTEL)
                return 0;

        if (PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_INTEL_PRO_WL_3945ABG_1 ||
            PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_INTEL_PRO_WL_3945ABG_2)
                return 1;

        return 0;
}

/* Base Address Register */
#define WPI_PCI_BAR0    0x10

static int
wpi_attach_once(void)
{

        mutex_init(&wpi_firmware_mutex, MUTEX_DEFAULT, IPL_NONE);
        return 0;
}

static void
wpi_attach(device_t parent __unused, device_t self, void *aux)
{
        struct wpi_softc *sc = device_private(self);
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = &sc->sc_ec.ec_if;
        struct pci_attach_args *pa = aux;
        const char *intrstr;
        bus_space_tag_t memt;
        bus_space_handle_t memh;
        pcireg_t data;
        int ac, error;
        char intrbuf[PCI_INTRSTR_LEN];

        RUN_ONCE(&wpi_firmware_init, wpi_attach_once);
        sc->fw_used = false;

        sc->sc_dev = self;
        sc->sc_pct = pa->pa_pc;
        sc->sc_pcitag = pa->pa_tag;

        sc->sc_rsw_status = WPI_RSW_UNKNOWN;
        sc->sc_rsw.smpsw_name = device_xname(self);
        sc->sc_rsw.smpsw_type = PSWITCH_TYPE_RADIO;
        error = sysmon_pswitch_register(&sc->sc_rsw);
        if (error) {
                aprint_error_dev(self,
                    "unable to register radio switch with sysmon\n");
                return;
        }
        mutex_init(&sc->sc_rsw_mtx, MUTEX_DEFAULT, IPL_NONE);
        cv_init(&sc->sc_rsw_cv, "wpirsw");
        sc->sc_rsw_suspend = false;
        sc->sc_rsw_suspended = false;
        if (kthread_create(PRI_NONE, 0, NULL,
            wpi_rsw_thread, sc, &sc->sc_rsw_lwp, "%s", device_xname(self))) {
                aprint_error_dev(self, "couldn't create switch thread\n");
        }

        callout_init(&sc->calib_to, 0);
        callout_setfunc(&sc->calib_to, wpi_calib_timeout, sc);

        pci_aprint_devinfo(pa, NULL);

        /* enable bus-mastering */
        data = pci_conf_read(sc->sc_pct, sc->sc_pcitag, PCI_COMMAND_STATUS_REG);
        data |= PCI_COMMAND_MASTER_ENABLE;
        pci_conf_write(sc->sc_pct, sc->sc_pcitag, PCI_COMMAND_STATUS_REG, data);

        /* map the register window */
        error = pci_mapreg_map(pa, WPI_PCI_BAR0, PCI_MAPREG_TYPE_MEM |
            PCI_MAPREG_MEM_TYPE_32BIT, 0, &memt, &memh, NULL, &sc->sc_sz);
        if (error != 0) {
                aprint_error_dev(self, "could not map memory space\n");
                return;
        }

        sc->sc_st = memt;
        sc->sc_sh = memh;
        sc->sc_dmat = pa->pa_dmat;

        sc->sc_soft_ih = softint_establish(SOFTINT_NET, wpi_softintr, sc);
        if (sc->sc_soft_ih == NULL) {
                aprint_error_dev(self, "could not establish softint\n");
                goto unmap;
        }

        if (pci_intr_alloc(pa, &sc->sc_pihp, NULL, 0)) {
                aprint_error_dev(self, "could not map interrupt\n");
                goto failsi;
        }

        intrstr = pci_intr_string(sc->sc_pct, sc->sc_pihp[0], intrbuf,
            sizeof(intrbuf));
        sc->sc_ih = pci_intr_establish_xname(sc->sc_pct, sc->sc_pihp[0],
            IPL_NET, wpi_intr, sc, device_xname(self));
        if (sc->sc_ih == NULL) {
                aprint_error_dev(self, "could not establish interrupt");
                if (intrstr != NULL)
                        aprint_error(" at %s", intrstr);
                aprint_error("\n");
                goto failia;
        }
        aprint_normal_dev(self, "interrupting at %s\n", intrstr);

        /*
         * Put adapter into a known state.
         */
        if ((error = wpi_reset(sc)) != 0) {
                aprint_error_dev(self, "could not reset adapter\n");
                goto failih;
        }

        /*
         * Allocate DMA memory for firmware transfers.
         */
        if ((error = wpi_alloc_fwmem(sc)) != 0) {
                aprint_error_dev(self, "could not allocate firmware memory\n");
                goto failih;
        }

        /*
         * Allocate shared page and Tx/Rx rings.
         */
        if ((error = wpi_alloc_shared(sc)) != 0) {
                aprint_error_dev(self, "could not allocate shared area\n");
                goto fail1;
        }

        if ((error = wpi_alloc_rpool(sc)) != 0) {
                aprint_error_dev(self, "could not allocate Rx buffers\n");
                goto fail2;
        }

        for (ac = 0; ac < 4; ac++) {
                error = wpi_alloc_tx_ring(sc, &sc->txq[ac], WPI_TX_RING_COUNT,
                    ac);
                if (error != 0) {
                        aprint_error_dev(self,
                            "could not allocate Tx ring %d\n", ac);
                        goto fail3;
                }
        }

        error = wpi_alloc_tx_ring(sc, &sc->cmdq, WPI_CMD_RING_COUNT, 4);
        if (error != 0) {
                aprint_error_dev(self, "could not allocate command ring\n");
                goto fail3;
        }

        error = wpi_alloc_rx_ring(sc, &sc->rxq);
        if (error != 0) {
                aprint_error_dev(self, "could not allocate Rx ring\n");
                goto fail4;
        }

        ic->ic_ifp = ifp;
        ic->ic_phytype = IEEE80211_T_OFDM;      /* not only, but not used */
        ic->ic_opmode = IEEE80211_M_STA;        /* default to BSS mode */
        ic->ic_state = IEEE80211_S_INIT;

        /* set device capabilities */
        ic->ic_caps =
            IEEE80211_C_WPA |           /* 802.11i */
            IEEE80211_C_MONITOR |       /* monitor mode supported */
            IEEE80211_C_TXPMGT |        /* tx power management */
            IEEE80211_C_SHSLOT |        /* short slot time supported */
            IEEE80211_C_SHPREAMBLE |    /* short preamble supported */
            IEEE80211_C_WME;            /* 802.11e */

        /* read supported channels and MAC address from EEPROM */
        wpi_read_eeprom(sc);

        /* set supported .11a, .11b and .11g rates */
        ic->ic_sup_rates[IEEE80211_MODE_11A] = ieee80211_std_rateset_11a;
        ic->ic_sup_rates[IEEE80211_MODE_11B] = ieee80211_std_rateset_11b;
        ic->ic_sup_rates[IEEE80211_MODE_11G] = ieee80211_std_rateset_11g;

        /* IBSS channel undefined for now */
        ic->ic_ibss_chan = &ic->ic_channels[0];

        ifp->if_softc = sc;
        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_init = wpi_init;
        ifp->if_stop = wpi_stop;
        ifp->if_ioctl = wpi_ioctl;
        ifp->if_start = wpi_start;
        ifp->if_watchdog = wpi_watchdog;
        IFQ_SET_READY(&ifp->if_snd);
        memcpy(ifp->if_xname, device_xname(self), IFNAMSIZ);

        if_initialize(ifp);
        ieee80211_ifattach(ic);
        /* Use common softint-based if_input */
        ifp->if_percpuq = if_percpuq_create(ifp);
        if_register(ifp);

        /* override default methods */
        ic->ic_node_alloc = wpi_node_alloc;
        ic->ic_newassoc = wpi_newassoc;
        ic->ic_wme.wme_update = wpi_wme_update;

        /* override state transition machine */
        sc->sc_newstate = ic->ic_newstate;
        ic->ic_newstate = wpi_newstate;

        /* XXX media locking needs revisiting */
        mutex_init(&sc->sc_media_mtx, MUTEX_DEFAULT, IPL_SOFTNET);
        ieee80211_media_init_with_lock(ic,
            wpi_media_change, ieee80211_media_status, &sc->sc_media_mtx);

        sc->amrr.amrr_min_success_threshold =  1;
        sc->amrr.amrr_max_success_threshold = 15;

        wpi_sysctlattach(sc);

        if (pmf_device_register(self, NULL, wpi_resume))
                pmf_class_network_register(self, ifp);
        else
                aprint_error_dev(self, "couldn't establish power handler\n");

        bpf_attach2(ifp, DLT_IEEE802_11_RADIO,
            sizeof(struct ieee80211_frame) + IEEE80211_RADIOTAP_HDRLEN,
            &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(WPI_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(WPI_TX_RADIOTAP_PRESENT);

        ieee80211_announce(ic);

        return;

        /* free allocated memory if something failed during attachment */
fail4:  wpi_free_tx_ring(sc, &sc->cmdq);
fail3:  while (--ac >= 0)
                wpi_free_tx_ring(sc, &sc->txq[ac]);
        wpi_free_rpool(sc);
fail2:  wpi_free_shared(sc);
fail1:  wpi_free_fwmem(sc);
failih: pci_intr_disestablish(sc->sc_pct, sc->sc_ih);
        sc->sc_ih = NULL;
failia: pci_intr_release(sc->sc_pct, sc->sc_pihp, 1);
        sc->sc_pihp = NULL;
failsi: softint_disestablish(sc->sc_soft_ih);
        sc->sc_soft_ih = NULL;
unmap:  bus_space_unmap(sc->sc_st, sc->sc_sh, sc->sc_sz);
}

static int
wpi_detach(device_t self, int flags __unused)
{
        struct wpi_softc *sc = device_private(self);
        struct ifnet *ifp = sc->sc_ic.ic_ifp;
        int ac;

        wpi_stop(ifp, 1);

        if (ifp != NULL)
                bpf_detach(ifp);
        ieee80211_ifdetach(&sc->sc_ic);
        if (ifp != NULL)
                if_detach(ifp);

        for (ac = 0; ac < 4; ac++)
                wpi_free_tx_ring(sc, &sc->txq[ac]);
        wpi_free_tx_ring(sc, &sc->cmdq);
        wpi_free_rx_ring(sc, &sc->rxq);
        wpi_free_rpool(sc);
        wpi_free_shared(sc);

        if (sc->sc_ih != NULL) {
                pci_intr_disestablish(sc->sc_pct, sc->sc_ih);
                sc->sc_ih = NULL;
        }
        if (sc->sc_pihp != NULL) {
                pci_intr_release(sc->sc_pct, sc->sc_pihp, 1);
                sc->sc_pihp = NULL;
        }
        if (sc->sc_soft_ih != NULL) {
                softint_disestablish(sc->sc_soft_ih);
                sc->sc_soft_ih = NULL;
        }

        mutex_enter(&sc->sc_rsw_mtx);
        sc->sc_dying = 1;
        cv_signal(&sc->sc_rsw_cv);
        while (sc->sc_rsw_lwp != NULL)
                cv_wait(&sc->sc_rsw_cv, &sc->sc_rsw_mtx);
        mutex_exit(&sc->sc_rsw_mtx);
        sysmon_pswitch_unregister(&sc->sc_rsw);

        bus_space_unmap(sc->sc_st, sc->sc_sh, sc->sc_sz);

        if (sc->fw_used) {
                sc->fw_used = false;
                wpi_release_firmware();
        }
        cv_destroy(&sc->sc_rsw_cv);
        mutex_destroy(&sc->sc_rsw_mtx);
        return 0;
}

static int
wpi_dma_contig_alloc(bus_dma_tag_t tag, struct wpi_dma_info *dma, void **kvap,
    bus_size_t size, bus_size_t alignment, int flags)
{
        int nsegs, error;

        dma->tag = tag;
        dma->size = size;

        error = bus_dmamap_create(tag, size, 1, size, 0, flags, &dma->map);
        if (error != 0)
                goto fail;

        error = bus_dmamem_alloc(tag, size, alignment, 0, &dma->seg, 1, &nsegs,
            flags);
        if (error != 0)
                goto fail;

        error = bus_dmamem_map(tag, &dma->seg, 1, size, &dma->vaddr, flags);
        if (error != 0)
                goto fail;

        error = bus_dmamap_load(tag, dma->map, dma->vaddr, size, NULL, flags);
        if (error != 0)
                goto fail;

        memset(dma->vaddr, 0, size);
        bus_dmamap_sync(dma->tag, dma->map, 0, size, BUS_DMASYNC_PREWRITE);

        dma->paddr = dma->map->dm_segs[0].ds_addr;
        if (kvap != NULL)
                *kvap = dma->vaddr;

        return 0;

fail:   wpi_dma_contig_free(dma);
        return error;
}

static void
wpi_dma_contig_free(struct wpi_dma_info *dma)
{
        if (dma->map != NULL) {
                if (dma->vaddr != NULL) {
                        bus_dmamap_unload(dma->tag, dma->map);
                        bus_dmamem_unmap(dma->tag, dma->vaddr, dma->size);
                        bus_dmamem_free(dma->tag, &dma->seg, 1);
                        dma->vaddr = NULL;
                }
                bus_dmamap_destroy(dma->tag, dma->map);
                dma->map = NULL;
        }
}

/*
 * Allocate a shared page between host and NIC.
 */
static int
wpi_alloc_shared(struct wpi_softc *sc)
{
        int error;

        /* must be aligned on a 4K-page boundary */
        error = wpi_dma_contig_alloc(sc->sc_dmat, &sc->shared_dma,
            (void **)&sc->shared, sizeof (struct wpi_shared), WPI_BUF_ALIGN,
            BUS_DMA_NOWAIT);
        if (error != 0)
                aprint_error_dev(sc->sc_dev,
                    "could not allocate shared area DMA memory\n");

        return error;
}

static void
wpi_free_shared(struct wpi_softc *sc)
{
        wpi_dma_contig_free(&sc->shared_dma);
}

/*
 * Allocate DMA-safe memory for firmware transfer.
 */
static int
wpi_alloc_fwmem(struct wpi_softc *sc)
{
        int error;

        /* allocate enough contiguous space to store text and data */
        error = wpi_dma_contig_alloc(sc->sc_dmat, &sc->fw_dma, NULL,
            WPI_FW_MAIN_TEXT_MAXSZ + WPI_FW_MAIN_DATA_MAXSZ, 0,
            BUS_DMA_NOWAIT);

        if (error != 0)
                aprint_error_dev(sc->sc_dev,
                    "could not allocate firmware transfer area DMA memory\n");
        return error;
}

static void
wpi_free_fwmem(struct wpi_softc *sc)
{
        wpi_dma_contig_free(&sc->fw_dma);
}

static struct wpi_rbuf *
wpi_alloc_rbuf(struct wpi_softc *sc)
{
        struct wpi_rbuf *rbuf;

        mutex_enter(&sc->rxq.freelist_mtx);
        rbuf = SLIST_FIRST(&sc->rxq.freelist);
        if (rbuf != NULL) {
                SLIST_REMOVE_HEAD(&sc->rxq.freelist, next);
        }
        mutex_exit(&sc->rxq.freelist_mtx);

        return rbuf;
}

/*
 * This is called automatically by the network stack when the mbuf to which our
 * Rx buffer is attached is freed.
 */
static void
wpi_free_rbuf(struct mbuf* m, void *buf, size_t size, void *arg)
{
        struct wpi_rbuf *rbuf = arg;
        struct wpi_softc *sc = rbuf->sc;

        /* put the buffer back in the free list */

        mutex_enter(&sc->rxq.freelist_mtx);
        SLIST_INSERT_HEAD(&sc->rxq.freelist, rbuf, next);
        mutex_exit(&sc->rxq.freelist_mtx);

        if (__predict_true(m != NULL))
                pool_cache_put(mb_cache, m);
}

static int
wpi_alloc_rpool(struct wpi_softc *sc)
{
        struct wpi_rx_ring *ring = &sc->rxq;
        int i, error;

        /* allocate a big chunk of DMA'able memory.. */
        error = wpi_dma_contig_alloc(sc->sc_dmat, &ring->buf_dma, NULL,
            WPI_RBUF_COUNT * WPI_RBUF_SIZE, WPI_BUF_ALIGN, BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_normal_dev(sc->sc_dev,
                    "could not allocate Rx buffers DMA memory\n");
                return error;
        }

        /* ..and split it into 3KB chunks */
        mutex_init(&ring->freelist_mtx, MUTEX_DEFAULT, IPL_NET);
        SLIST_INIT(&ring->freelist);
        for (i = 0; i < WPI_RBUF_COUNT; i++) {
                struct wpi_rbuf *rbuf = &ring->rbuf[i];

                rbuf->sc = sc;  /* backpointer for callbacks */
                rbuf->vaddr = (char *)ring->buf_dma.vaddr + i * WPI_RBUF_SIZE;
                rbuf->paddr = ring->buf_dma.paddr + i * WPI_RBUF_SIZE;

                SLIST_INSERT_HEAD(&ring->freelist, rbuf, next);
        }

        return 0;
}

static void
wpi_free_rpool(struct wpi_softc *sc)
{
        mutex_destroy(&sc->rxq.freelist_mtx);
        wpi_dma_contig_free(&sc->rxq.buf_dma);
}

static int
wpi_alloc_rx_ring(struct wpi_softc *sc, struct wpi_rx_ring *ring)
{
        bus_size_t size;
        int i, error;

        ring->cur = 0;

        size = WPI_RX_RING_COUNT * sizeof (struct wpi_rx_desc);
        error = wpi_dma_contig_alloc(sc->sc_dmat, &ring->desc_dma,
            (void **)&ring->desc, size,
            WPI_RING_DMA_ALIGN, BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not allocate rx ring DMA memory\n");
                goto fail;
        }

        /*
         * Setup Rx buffers.
         */
        for (i = 0; i < WPI_RX_RING_COUNT; i++) {
                struct wpi_rx_data *data = &ring->data[i];
                struct wpi_rbuf *rbuf;

                error = bus_dmamap_create(sc->sc_dmat, WPI_RBUF_SIZE, 1,
                    WPI_RBUF_SIZE, 0, BUS_DMA_NOWAIT, &data->map);
                if (error) {
                        aprint_error_dev(sc->sc_dev,
                            "could not allocate rx dma map\n");
                        goto fail;
                }

                MGETHDR(data->m, M_DONTWAIT, MT_DATA);
                if (data->m == NULL) {
                        aprint_error_dev(sc->sc_dev,
                            "could not allocate rx mbuf\n");
                        error = ENOMEM;
                        goto fail;
                }
                if ((rbuf = wpi_alloc_rbuf(sc)) == NULL) {
                        m_freem(data->m);
                        data->m = NULL;
                        aprint_error_dev(sc->sc_dev,
                            "could not allocate rx cluster\n");
                        error = ENOMEM;
                        goto fail;
                }
                /* attach Rx buffer to mbuf */
                MEXTADD(data->m, rbuf->vaddr, WPI_RBUF_SIZE, 0, wpi_free_rbuf,
                    rbuf);
                data->m->m_flags |= M_EXT_RW;

                error = bus_dmamap_load(sc->sc_dmat, data->map,
                    mtod(data->m, void *), WPI_RBUF_SIZE, NULL,
                    BUS_DMA_NOWAIT | BUS_DMA_READ);
                if (error) {
                        aprint_error_dev(sc->sc_dev,
                            "could not load mbuf: %d\n", error);
                        goto fail;
                }

                ring->desc[i] = htole32(rbuf->paddr);
        }

        bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map, 0, size,
            BUS_DMASYNC_PREWRITE);

        return 0;

fail:   wpi_free_rx_ring(sc, ring);
        return error;
}

static void
wpi_reset_rx_ring(struct wpi_softc *sc, struct wpi_rx_ring *ring)
{
        int ntries;

        wpi_mem_lock(sc);

        WPI_WRITE(sc, WPI_RX_CONFIG, 0);
        for (ntries = 0; ntries < 100; ntries++) {
                if (WPI_READ(sc, WPI_RX_STATUS) & WPI_RX_IDLE)
                        break;
                DELAY(10);
        }
#ifdef WPI_DEBUG
        if (ntries == 100 && wpi_debug > 0)
                aprint_error_dev(sc->sc_dev, "timeout resetting Rx ring\n");
#endif
        wpi_mem_unlock(sc);

        ring->cur = 0;
}

static void
wpi_free_rx_ring(struct wpi_softc *sc, struct wpi_rx_ring *ring)
{
        int i;

        wpi_dma_contig_free(&ring->desc_dma);

        for (i = 0; i < WPI_RX_RING_COUNT; i++) {
                if (ring->data[i].m != NULL) {
                        bus_dmamap_unload(sc->sc_dmat, ring->data[i].map);
                        m_freem(ring->data[i].m);
                }
                if (ring->data[i].map != NULL) {
                        bus_dmamap_destroy(sc->sc_dmat, ring->data[i].map);
                }
        }
}

static int
wpi_alloc_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring, int count,
    int qid)
{
        int i, error;

        ring->qid = qid;
        ring->count = count;
        ring->queued = 0;
        ring->cur = 0;

        error = wpi_dma_contig_alloc(sc->sc_dmat, &ring->desc_dma,
            (void **)&ring->desc, count * sizeof (struct wpi_tx_desc),
            WPI_RING_DMA_ALIGN, BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not allocate tx ring DMA memory\n");
                goto fail;
        }

        /* update shared page with ring's base address */
        sc->shared->txbase[qid] = htole32(ring->desc_dma.paddr);
        bus_dmamap_sync(sc->sc_dmat, sc->shared_dma.map, 0,
            sizeof(struct wpi_shared), BUS_DMASYNC_PREWRITE);

        error = wpi_dma_contig_alloc(sc->sc_dmat, &ring->cmd_dma,
            (void **)&ring->cmd, count * sizeof (struct wpi_tx_cmd), 4,
            BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not allocate tx cmd DMA memory\n");
                goto fail;
        }

        ring->data = malloc(count * sizeof (struct wpi_tx_data), M_DEVBUF,
            M_WAITOK | M_ZERO);

        for (i = 0; i < count; i++) {
                struct wpi_tx_data *data = &ring->data[i];

                error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
                    WPI_MAX_SCATTER - 1, MCLBYTES, 0, BUS_DMA_NOWAIT,
                    &data->map);
                if (error != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "could not create tx buf DMA map\n");
                        goto fail;
                }
        }

        return 0;

fail:   wpi_free_tx_ring(sc, ring);
        return error;
}

static void
wpi_reset_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring)
{
        int i, ntries;

        wpi_mem_lock(sc);

        WPI_WRITE(sc, WPI_TX_CONFIG(ring->qid), 0);
        for (ntries = 0; ntries < 100; ntries++) {
                if (WPI_READ(sc, WPI_TX_STATUS) & WPI_TX_IDLE(ring->qid))
                        break;
                DELAY(10);
        }
#ifdef WPI_DEBUG
        if (ntries == 100 && wpi_debug > 0) {
                aprint_error_dev(sc->sc_dev, "timeout resetting Tx ring %d\n",
                    ring->qid);
        }
#endif
        wpi_mem_unlock(sc);

        for (i = 0; i < ring->count; i++) {
                struct wpi_tx_data *data = &ring->data[i];

                if (data->m != NULL) {
                        bus_dmamap_unload(sc->sc_dmat, data->map);
                        m_freem(data->m);
                        data->m = NULL;
                }
        }

        ring->queued = 0;
        ring->cur = 0;
}

static void
wpi_free_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring)
{
        int i;

        wpi_dma_contig_free(&ring->desc_dma);
        wpi_dma_contig_free(&ring->cmd_dma);

        if (ring->data != NULL) {
                for (i = 0; i < ring->count; i++) {
                        struct wpi_tx_data *data = &ring->data[i];

                        if (data->m != NULL) {
                                bus_dmamap_unload(sc->sc_dmat, data->map);
                                m_freem(data->m);
                        }
                }
                free(ring->data, M_DEVBUF);
        }
}

/*ARGUSED*/
static struct ieee80211_node *
wpi_node_alloc(struct ieee80211_node_table *nt __unused)
{
        struct wpi_node *wn;

        wn = malloc(sizeof (struct wpi_node), M_80211_NODE, M_NOWAIT | M_ZERO);

        return (struct ieee80211_node *)wn;
}

static void
wpi_newassoc(struct ieee80211_node *ni, int isnew)
{
        struct wpi_softc *sc = ni->ni_ic->ic_ifp->if_softc;
        int i;

        ieee80211_amrr_node_init(&sc->amrr, &((struct wpi_node *)ni)->amn);

        /* set rate to some reasonable initial value */
        for (i = ni->ni_rates.rs_nrates - 1;
             i > 0 && (ni->ni_rates.rs_rates[i] & IEEE80211_RATE_VAL) > 72;
             i--);
        ni->ni_txrate = i;
}

static int
wpi_media_change(struct ifnet *ifp)
{
        int error;

        error = ieee80211_media_change(ifp);
        if (error != ENETRESET)
                return error;

        if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == (IFF_UP | IFF_RUNNING))
                wpi_init(ifp);

        return 0;
}

static int
wpi_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
{
        struct ifnet *ifp = ic->ic_ifp;
        struct wpi_softc *sc = ifp->if_softc;
        struct ieee80211_node *ni;
        enum ieee80211_state ostate = ic->ic_state;
        int error;

        callout_stop(&sc->calib_to);

        switch (nstate) {
        case IEEE80211_S_SCAN:
        
                if (sc->is_scanning)
                        break;

                sc->is_scanning = true;

                if (ostate != IEEE80211_S_SCAN) {
                        /* make the link LED blink while we're scanning */
                        wpi_set_led(sc, WPI_LED_LINK, 20, 2);
                }

                if ((error = wpi_scan(sc)) != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "could not initiate scan\n");
                        return error;
                }
                break;

        case IEEE80211_S_ASSOC:
                if (ic->ic_state != IEEE80211_S_RUN)
                        break;
                /* FALLTHROUGH */
        case IEEE80211_S_AUTH:
                /* reset state to handle reassociations correctly */
                sc->config.associd = 0;
                sc->config.filter &= ~htole32(WPI_FILTER_BSS);

                if ((error = wpi_auth(sc)) != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "could not send authentication request\n");
                        return error;
                }
                break;

        case IEEE80211_S_RUN:
                if (ic->ic_opmode == IEEE80211_M_MONITOR) {
                        /* link LED blinks while monitoring */
                        wpi_set_led(sc, WPI_LED_LINK, 5, 5);
                        break;
                }
                ni = ic->ic_bss;

                if (ic->ic_opmode != IEEE80211_M_STA) {
                        (void) wpi_auth(sc);    /* XXX */
                        wpi_setup_beacon(sc, ni);
                }

                wpi_enable_tsf(sc, ni);

                /* update adapter's configuration */
                sc->config.associd = htole16(ni->ni_associd & ~0xc000);
                /* short preamble/slot time are negotiated when associating */
                sc->config.flags &= ~htole32(WPI_CONFIG_SHPREAMBLE |
                    WPI_CONFIG_SHSLOT);
                if (ic->ic_flags & IEEE80211_F_SHSLOT)
                        sc->config.flags |= htole32(WPI_CONFIG_SHSLOT);
                if (ic->ic_flags & IEEE80211_F_SHPREAMBLE)
                        sc->config.flags |= htole32(WPI_CONFIG_SHPREAMBLE);
                sc->config.filter |= htole32(WPI_FILTER_BSS);
                if (ic->ic_opmode != IEEE80211_M_STA)
                        sc->config.filter |= htole32(WPI_FILTER_BEACON);

/* XXX put somewhere HC_QOS_SUPPORT_ASSOC + HC_IBSS_START */

                DPRINTF(("config chan %d flags %x\n", sc->config.chan,
                    sc->config.flags));
                error = wpi_cmd(sc, WPI_CMD_CONFIGURE, &sc->config,
                    sizeof (struct wpi_config), 1);
                if (error != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "could not update configuration\n");
                        return error;
                }

                /* configuration has changed, set Tx power accordingly */
                if ((error = wpi_set_txpower(sc, ic->ic_curchan, 1)) != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "could not set Tx power\n");
                        return error;
                }

                if (ic->ic_opmode == IEEE80211_M_STA) {
                        /* fake a join to init the tx rate */
                        wpi_newassoc(ni, 1);
                }

                /* start periodic calibration timer */
                sc->calib_cnt = 0;
                callout_schedule(&sc->calib_to, hz/2);

                /* link LED always on while associated */
                wpi_set_led(sc, WPI_LED_LINK, 0, 1);
                break;

        case IEEE80211_S_INIT:
                sc->is_scanning = false;
                break;
        }

        return sc->sc_newstate(ic, nstate, arg);
}

/*
 * Grab exclusive access to NIC memory.
 */
static void
wpi_mem_lock(struct wpi_softc *sc)
{
        uint32_t tmp;
        int ntries;

        tmp = WPI_READ(sc, WPI_GPIO_CTL);
        WPI_WRITE(sc, WPI_GPIO_CTL, tmp | WPI_GPIO_MAC);

        /* spin until we actually get the lock */
        for (ntries = 0; ntries < 1000; ntries++) {
                if ((WPI_READ(sc, WPI_GPIO_CTL) &
                    (WPI_GPIO_CLOCK | WPI_GPIO_SLEEP)) == WPI_GPIO_CLOCK)
                        break;
                DELAY(10);
        }
        if (ntries == 1000)
                aprint_error_dev(sc->sc_dev, "could not lock memory\n");
}

/*
 * Release lock on NIC memory.
 */
static void
wpi_mem_unlock(struct wpi_softc *sc)
{
        uint32_t tmp = WPI_READ(sc, WPI_GPIO_CTL);
        WPI_WRITE(sc, WPI_GPIO_CTL, tmp & ~WPI_GPIO_MAC);
}

static uint32_t
wpi_mem_read(struct wpi_softc *sc, uint16_t addr)
{
        WPI_WRITE(sc, WPI_READ_MEM_ADDR, WPI_MEM_4 | addr);
        return WPI_READ(sc, WPI_READ_MEM_DATA);
}

static void
wpi_mem_write(struct wpi_softc *sc, uint16_t addr, uint32_t data)
{
        WPI_WRITE(sc, WPI_WRITE_MEM_ADDR, WPI_MEM_4 | addr);
        WPI_WRITE(sc, WPI_WRITE_MEM_DATA, data);
}

static void
wpi_mem_write_region_4(struct wpi_softc *sc, uint16_t addr,
    const uint32_t *data, int wlen)
{
        for (; wlen > 0; wlen--, data++, addr += 4)
                wpi_mem_write(sc, addr, *data);
}

/*
 * Read `len' bytes from the EEPROM.  We access the EEPROM through the MAC
 * instead of using the traditional bit-bang method.
 */
static int
wpi_read_prom_data(struct wpi_softc *sc, uint32_t addr, void *data, int len)
{
        uint8_t *out = data;
        uint32_t val;
        int ntries;

        wpi_mem_lock(sc);
        for (; len > 0; len -= 2, addr++) {
                WPI_WRITE(sc, WPI_EEPROM_CTL, addr << 2);

                for (ntries = 0; ntries < 10; ntries++) {
                        if ((val = WPI_READ(sc, WPI_EEPROM_CTL)) &
                            WPI_EEPROM_READY)
                                break;
                        DELAY(5);
                }
                if (ntries == 10) {
                        aprint_error_dev(sc->sc_dev, "could not read EEPROM\n");
                        return ETIMEDOUT;
                }
                *out++ = val >> 16;
                if (len > 1)
                        *out++ = val >> 24;
        }
        wpi_mem_unlock(sc);

        return 0;
}

/*
 * The firmware boot code is small and is intended to be copied directly into
 * the NIC internal memory.
 */
int
wpi_load_microcode(struct wpi_softc *sc, const uint8_t *ucode, int size)
{
        int ntries;

        size /= sizeof (uint32_t);

        wpi_mem_lock(sc);

        /* copy microcode image into NIC memory */
        wpi_mem_write_region_4(sc, WPI_MEM_UCODE_BASE,
            (const uint32_t *)ucode, size);

        wpi_mem_write(sc, WPI_MEM_UCODE_SRC, 0);
        wpi_mem_write(sc, WPI_MEM_UCODE_DST, WPI_FW_TEXT);
        wpi_mem_write(sc, WPI_MEM_UCODE_SIZE, size);

        /* run microcode */
        wpi_mem_write(sc, WPI_MEM_UCODE_CTL, WPI_UC_RUN);

        /* wait for transfer to complete */
        for (ntries = 0; ntries < 1000; ntries++) {
                if (!(wpi_mem_read(sc, WPI_MEM_UCODE_CTL) & WPI_UC_RUN))
                        break;
                DELAY(10);
        }
        if (ntries == 1000) {
                wpi_mem_unlock(sc);
                aprint_error_dev(sc->sc_dev, "could not load boot firmware\n");
                return ETIMEDOUT;
        }
        wpi_mem_write(sc, WPI_MEM_UCODE_CTL, WPI_UC_ENABLE);

        wpi_mem_unlock(sc);

        return 0;
}

static int
wpi_cache_firmware(struct wpi_softc *sc)
{
        const char *const fwname = wpi_firmware_name;
        firmware_handle_t fw;
        int error;

        /* sc is used here only to report error messages.  */

        mutex_enter(&wpi_firmware_mutex);

        if (wpi_firmware_users == SIZE_MAX) {
                mutex_exit(&wpi_firmware_mutex);
                return ENFILE;  /* Too many of something in the system...  */
        }
        if (wpi_firmware_users++) {
                KASSERT(wpi_firmware_image != NULL);
                KASSERT(wpi_firmware_size > 0);
                mutex_exit(&wpi_firmware_mutex);
                return 0;       /* Already good to go.  */
        }

        KASSERT(wpi_firmware_image == NULL);
        KASSERT(wpi_firmware_size == 0);

        /* load firmware image from disk */
        if ((error = firmware_open("if_wpi", fwname, &fw)) != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not open firmware file %s: %d\n", fwname, error);
                goto fail0;
        }

        wpi_firmware_size = firmware_get_size(fw);

        if (wpi_firmware_size > sizeof (struct wpi_firmware_hdr) +
            WPI_FW_MAIN_TEXT_MAXSZ + WPI_FW_MAIN_DATA_MAXSZ +
            WPI_FW_INIT_TEXT_MAXSZ + WPI_FW_INIT_DATA_MAXSZ +
            WPI_FW_BOOT_TEXT_MAXSZ) {
                aprint_error_dev(sc->sc_dev,
                    "firmware file %s too large: %zu bytes\n",
                    fwname, wpi_firmware_size);
                error = EFBIG;
                goto fail1;
        }

        if (wpi_firmware_size < sizeof (struct wpi_firmware_hdr)) {
                aprint_error_dev(sc->sc_dev,
                    "firmware file %s too small: %zu bytes\n",
                    fwname, wpi_firmware_size);
                error = EINVAL;
                goto fail1;
        }

        wpi_firmware_image = firmware_malloc(wpi_firmware_size);
        if (wpi_firmware_image == NULL) {
                aprint_error_dev(sc->sc_dev,
                    "not enough memory for firmware file %s\n", fwname);
                error = ENOMEM;
                goto fail1;
        }

        error = firmware_read(fw, 0, wpi_firmware_image, wpi_firmware_size);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev,
                    "error reading firmware file %s: %d\n", fwname, error);
                goto fail2;
        }

        /* Success!  */
        firmware_close(fw);
        mutex_exit(&wpi_firmware_mutex);
        return 0;

fail2:
        firmware_free(wpi_firmware_image, wpi_firmware_size);
        wpi_firmware_image = NULL;
fail1:
        wpi_firmware_size = 0;
        firmware_close(fw);
fail0:
        KASSERT(wpi_firmware_users == 1);
        wpi_firmware_users = 0;
        KASSERT(wpi_firmware_image == NULL);
        KASSERT(wpi_firmware_size == 0);

        mutex_exit(&wpi_firmware_mutex);
        return error;
}

static void
wpi_release_firmware(void)
{

        mutex_enter(&wpi_firmware_mutex);

        KASSERT(wpi_firmware_users > 0);
        KASSERT(wpi_firmware_image != NULL);
        KASSERT(wpi_firmware_size != 0);

        if (--wpi_firmware_users == 0) {
                firmware_free(wpi_firmware_image, wpi_firmware_size);
                wpi_firmware_image = NULL;
                wpi_firmware_size = 0;
        }

        mutex_exit(&wpi_firmware_mutex);
}

static int
wpi_load_firmware(struct wpi_softc *sc)
{
        struct wpi_dma_info *dma = &sc->fw_dma;
        struct wpi_firmware_hdr hdr;
        const uint8_t *init_text, *init_data, *main_text, *main_data;
        const uint8_t *boot_text;
        uint32_t init_textsz, init_datasz, main_textsz, main_datasz;
        uint32_t boot_textsz;
        size_t size;
        int error;

        if (!sc->fw_used) {
                if ((error = wpi_cache_firmware(sc)) != 0)
                        return error;
                sc->fw_used = true;
        }

        KASSERT(sc->fw_used);
        KASSERT(wpi_firmware_image != NULL);
        KASSERT(wpi_firmware_size > sizeof(hdr));

        memcpy(&hdr, wpi_firmware_image, sizeof(hdr));

        main_textsz = le32toh(hdr.main_textsz);
        main_datasz = le32toh(hdr.main_datasz);
        init_textsz = le32toh(hdr.init_textsz);
        init_datasz = le32toh(hdr.init_datasz);
        boot_textsz = le32toh(hdr.boot_textsz);

        /* sanity-check firmware segments sizes */
        if (main_textsz > WPI_FW_MAIN_TEXT_MAXSZ ||
            main_datasz > WPI_FW_MAIN_DATA_MAXSZ ||
            init_textsz > WPI_FW_INIT_TEXT_MAXSZ ||
            init_datasz > WPI_FW_INIT_DATA_MAXSZ ||
            boot_textsz > WPI_FW_BOOT_TEXT_MAXSZ ||
            (boot_textsz & 3) != 0) {
                aprint_error_dev(sc->sc_dev, "invalid firmware header\n");
                error = EINVAL;
                goto free_firmware;
        }

        /* check that all firmware segments are present */
        size = sizeof (struct wpi_firmware_hdr) + main_textsz +
            main_datasz + init_textsz + init_datasz + boot_textsz;
        if (wpi_firmware_size < size) {
                aprint_error_dev(sc->sc_dev,
                    "firmware file truncated: %zu bytes, expected %zu bytes\n",
                    wpi_firmware_size, size);
                error = EINVAL;
                goto free_firmware;
        }

        /* get pointers to firmware segments */
        main_text = wpi_firmware_image + sizeof (struct wpi_firmware_hdr);
        main_data = main_text + main_textsz;
        init_text = main_data + main_datasz;
        init_data = init_text + init_textsz;
        boot_text = init_data + init_datasz;

        /* copy initialization images into pre-allocated DMA-safe memory */
        memcpy(dma->vaddr, init_data, init_datasz);
        memcpy((char *)dma->vaddr + WPI_FW_INIT_DATA_MAXSZ, init_text,
            init_textsz);

        bus_dmamap_sync(dma->tag, dma->map, 0, dma->size, BUS_DMASYNC_PREWRITE);

        /* tell adapter where to find initialization images */
        wpi_mem_lock(sc);
        wpi_mem_write(sc, WPI_MEM_DATA_BASE, dma->paddr);
        wpi_mem_write(sc, WPI_MEM_DATA_SIZE, init_datasz);
        wpi_mem_write(sc, WPI_MEM_TEXT_BASE,
            dma->paddr + WPI_FW_INIT_DATA_MAXSZ);
        wpi_mem_write(sc, WPI_MEM_TEXT_SIZE, init_textsz);
        wpi_mem_unlock(sc);

        /* load firmware boot code */
        if ((error = wpi_load_microcode(sc, boot_text, boot_textsz)) != 0) {
                aprint_error_dev(sc->sc_dev, "could not load boot firmware\n");
                return error;
        }

        /* now press "execute" ;-) */
        WPI_WRITE(sc, WPI_RESET, 0);

        /* wait at most one second for first alive notification */
        if ((error = tsleep(sc, PCATCH, "wpiinit", hz)) != 0) {
                /* this isn't what was supposed to happen.. */
                aprint_error_dev(sc->sc_dev,
                    "timeout waiting for adapter to initialize\n");
        }

        /* copy runtime images into pre-allocated DMA-safe memory */
        memcpy(dma->vaddr, main_data, main_datasz);
        memcpy((char *)dma->vaddr + WPI_FW_MAIN_DATA_MAXSZ, main_text,
            main_textsz);

        bus_dmamap_sync(dma->tag, dma->map, 0, dma->size, BUS_DMASYNC_PREWRITE);

        /* tell adapter where to find runtime images */
        wpi_mem_lock(sc);
        wpi_mem_write(sc, WPI_MEM_DATA_BASE, dma->paddr);
        wpi_mem_write(sc, WPI_MEM_DATA_SIZE, main_datasz);
        wpi_mem_write(sc, WPI_MEM_TEXT_BASE,
            dma->paddr + WPI_FW_MAIN_DATA_MAXSZ);
        wpi_mem_write(sc, WPI_MEM_TEXT_SIZE, WPI_FW_UPDATED | main_textsz);
        wpi_mem_unlock(sc);

        /* wait at most one second for second alive notification */
        if ((error = tsleep(sc, PCATCH, "wpiinit", hz)) != 0) {
                /* this isn't what was supposed to happen.. */
                aprint_error_dev(sc->sc_dev,
                    "timeout waiting for adapter to initialize\n");
        }

        return error;

free_firmware:
        sc->fw_used = false;
        wpi_release_firmware();
        return error;
}

static void
wpi_calib_timeout(void *arg)
{
        struct wpi_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;
        int temp, s;

        /* automatic rate control triggered every 500ms */
        if (ic->ic_fixed_rate == -1) {
                s = splnet();
                if (ic->ic_opmode == IEEE80211_M_STA)
                        wpi_iter_func(sc, ic->ic_bss);
                else
                        ieee80211_iterate_nodes(&ic->ic_sta, wpi_iter_func, sc);
                splx(s);
        }

        /* update sensor data */
        temp = (int)WPI_READ(sc, WPI_TEMPERATURE);

        /* automatic power calibration every 60s */
        if (++sc->calib_cnt >= 120) {
                wpi_power_calibration(sc, temp);
                sc->calib_cnt = 0;
        }

        callout_schedule(&sc->calib_to, hz/2);
}

static void
wpi_iter_func(void *arg, struct ieee80211_node *ni)
{
        struct wpi_softc *sc = arg;
        struct wpi_node *wn = (struct wpi_node *)ni;

        ieee80211_amrr_choose(&sc->amrr, ni, &wn->amn);
}

/*
 * This function is called periodically (every 60 seconds) to adjust output
 * power to temperature changes.
 */
void
wpi_power_calibration(struct wpi_softc *sc, int temp)
{
        /* sanity-check read value */
        if (temp < -260 || temp > 25) {
                /* this can't be correct, ignore */
                DPRINTF(("out-of-range temperature reported: %d\n", temp));
                return;
        }

        DPRINTF(("temperature %d->%d\n", sc->temp, temp));

        /* adjust Tx power if need be */
        if (abs(temp - sc->temp) <= 6)
                return;

        sc->temp = temp;

        if (wpi_set_txpower(sc, sc->sc_ic.ic_curchan, 1) != 0) {
                /* just warn, too bad for the automatic calibration... */
                aprint_error_dev(sc->sc_dev, "could not adjust Tx power\n");
        }
}

static void
wpi_rx_intr(struct wpi_softc *sc, struct wpi_rx_desc *desc,
    struct wpi_rx_data *data)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct wpi_rx_ring *ring = &sc->rxq;
        struct wpi_rx_stat *stat;
        struct wpi_rx_head *head;
        struct wpi_rx_tail *tail;
        struct wpi_rbuf *rbuf;
        struct ieee80211_frame *wh;
        struct ieee80211_node *ni;
        struct mbuf *m, *mnew;
        int data_off, error, s;

        bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
            BUS_DMASYNC_POSTREAD);
        stat = (struct wpi_rx_stat *)(desc + 1);

        if (stat->len > WPI_STAT_MAXLEN) {
                aprint_error_dev(sc->sc_dev, "invalid rx statistic header\n");
                if_statinc(ifp, if_ierrors);
                return;
        }

        head = (struct wpi_rx_head *)((char *)(stat + 1) + stat->len);
        tail = (struct wpi_rx_tail *)((char *)(head + 1) + le16toh(head->len));

        DPRINTFN(4, ("rx intr: idx=%d len=%d stat len=%d rssi=%d rate=%x "
            "chan=%d tstamp=%" PRIu64 "\n", ring->cur, le32toh(desc->len),
            le16toh(head->len), (int8_t)stat->rssi, head->rate, head->chan,
            le64toh(tail->tstamp)));

        /*
         * Discard Rx frames with bad CRC early (XXX we may want to pass them
         * to radiotap in monitor mode).
         */
        if ((le32toh(tail->flags) & WPI_RX_NOERROR) != WPI_RX_NOERROR) {
                DPRINTF(("rx tail flags error %x\n",
                    le32toh(tail->flags)));
                if_statinc(ifp, if_ierrors);
                return;
        }

        /* Compute where are the useful datas */
        data_off = (char*)(head + 1) - mtod(data->m, char*);
                        
        MGETHDR(mnew, M_DONTWAIT, MT_DATA);
        if (mnew == NULL) {
                if_statinc(ifp, if_ierrors);
                return;
        }

        rbuf = wpi_alloc_rbuf(sc);
        if (rbuf == NULL) {
                m_freem(mnew);
                if_statinc(ifp, if_ierrors);
                return;
        }

        /* attach Rx buffer to mbuf */
        MEXTADD(mnew, rbuf->vaddr, WPI_RBUF_SIZE, 0, wpi_free_rbuf,
                rbuf);
        mnew->m_flags |= M_EXT_RW;

        bus_dmamap_unload(sc->sc_dmat, data->map);

        error = bus_dmamap_load(sc->sc_dmat, data->map,
            mtod(mnew, void *), WPI_RBUF_SIZE, NULL,
            BUS_DMA_NOWAIT | BUS_DMA_READ);
        if (error) {
                device_printf(sc->sc_dev,
                    "couldn't load rx mbuf: %d\n", error);
                m_freem(mnew);
                if_statinc(ifp, if_ierrors);

                error = bus_dmamap_load(sc->sc_dmat, data->map,
                    mtod(data->m, void *), WPI_RBUF_SIZE, NULL,
                    BUS_DMA_NOWAIT | BUS_DMA_READ);
                if (error)
                        panic("%s: bus_dmamap_load failed: %d\n",
                            device_xname(sc->sc_dev), error);
                return;
        }

        /* new mbuf loaded successfully */
        m = data->m;
        data->m = mnew;

        /* update Rx descriptor */
        ring->desc[ring->cur] = htole32(rbuf->paddr);
        bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map, 0,
            ring->desc_dma.size,
            BUS_DMASYNC_PREWRITE);

        m->m_data = (char*)m->m_data + data_off;
        m->m_pkthdr.len = m->m_len = le16toh(head->len);

        /* finalize mbuf */
        m_set_rcvif(m, ifp);

        s = splnet();

        if (sc->sc_drvbpf != NULL) {
                struct wpi_rx_radiotap_header *tap = &sc->sc_rxtap;

                tap->wr_flags = 0;
                tap->wr_chan_freq =
                    htole16(ic->ic_channels[head->chan].ic_freq);
                tap->wr_chan_flags =
                    htole16(ic->ic_channels[head->chan].ic_flags);
                tap->wr_dbm_antsignal = (int8_t)(stat->rssi - WPI_RSSI_OFFSET);
                tap->wr_dbm_antnoise = (int8_t)le16toh(stat->noise);
                tap->wr_tsft = tail->tstamp;
                tap->wr_antenna = (le16toh(head->flags) >> 4) & 0xf;
                switch (head->rate) {
                /* CCK rates */
                case  10: tap->wr_rate =   2; break;
                case  20: tap->wr_rate =   4; break;
                case  55: tap->wr_rate =  11; break;
                case 110: tap->wr_rate =  22; break;
                /* OFDM rates */
                case 0xd: tap->wr_rate =  12; break;
                case 0xf: tap->wr_rate =  18; break;
                case 0x5: tap->wr_rate =  24; break;
                case 0x7: tap->wr_rate =  36; break;
                case 0x9: tap->wr_rate =  48; break;
                case 0xb: tap->wr_rate =  72; break;
                case 0x1: tap->wr_rate =  96; break;
                case 0x3: tap->wr_rate = 108; break;
                /* unknown rate: should not happen */
                default:  tap->wr_rate =   0;
                }
                if (le16toh(head->flags) & 0x4)
                        tap->wr_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;

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

        /* grab a reference to the source node */
        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, stat->rssi, 0);

        /* release node reference */
        ieee80211_free_node(ni);

        splx(s);
}

static void
wpi_tx_intr(struct wpi_softc *sc, struct wpi_rx_desc *desc)
{
        struct ifnet *ifp = sc->sc_ic.ic_ifp;
        struct wpi_tx_ring *ring = &sc->txq[desc->qid & 0x3];
        struct wpi_tx_data *data = &ring->data[desc->idx];
        struct wpi_tx_stat *stat = (struct wpi_tx_stat *)(desc + 1);
        struct wpi_node *wn = (struct wpi_node *)data->ni;
        int s;

        DPRINTFN(4, ("tx done: qid=%d idx=%d retries=%d nkill=%d rate=%x "
            "duration=%d status=%x\n", desc->qid, desc->idx, stat->ntries,
            stat->nkill, stat->rate, le32toh(stat->duration),
            le32toh(stat->status)));

        s = splnet();

        /*
         * Update rate control statistics for the node.
         * XXX we should not count mgmt frames since they're always sent at
         * the lowest available bit-rate.
         */
        wn->amn.amn_txcnt++;
        if (stat->ntries > 0) {
                DPRINTFN(3, ("tx intr ntries %d\n", stat->ntries));
                wn->amn.amn_retrycnt++;
        }

        if ((le32toh(stat->status) & 0xff) != 1)
                if_statinc(ifp, if_oerrors);
        else
                if_statinc(ifp, if_opackets);

        bus_dmamap_unload(sc->sc_dmat, data->map);
        m_freem(data->m);
        data->m = NULL;
        ieee80211_free_node(data->ni);
        data->ni = NULL;

        ring->queued--;

        sc->sc_tx_timer = 0;
        ifp->if_flags &= ~IFF_OACTIVE;
        wpi_start(ifp); /* in softint */

        splx(s);
}

static void
wpi_cmd_intr(struct wpi_softc *sc, struct wpi_rx_desc *desc)
{
        struct wpi_tx_ring *ring = &sc->cmdq;
        struct wpi_tx_data *data;

        if ((desc->qid & 7) != 4)
                return; /* not a command ack */

        data = &ring->data[desc->idx];

        /* if the command was mapped in a mbuf, free it */
        if (data->m != NULL) {
                bus_dmamap_unload(sc->sc_dmat, data->map);
                m_freem(data->m);
                data->m = NULL;
        }

        wakeup(&ring->cmd[desc->idx]);
}

static void
wpi_notif_intr(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp =  ic->ic_ifp;
        uint32_t hw;
        int s;

        bus_dmamap_sync(sc->sc_dmat, sc->shared_dma.map, 0,
            sizeof(struct wpi_shared), BUS_DMASYNC_POSTREAD);

        hw = le32toh(sc->shared->next);
        while (sc->rxq.cur != hw) {
                struct wpi_rx_data *data = &sc->rxq.data[sc->rxq.cur];
                struct wpi_rx_desc *desc;

                bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
                    BUS_DMASYNC_POSTREAD);
                desc = mtod(data->m, struct wpi_rx_desc *);

                DPRINTFN(4, ("rx notification qid=%x idx=%d flags=%x type=%d "
                    "len=%d\n", desc->qid, desc->idx, desc->flags,
                    desc->type, le32toh(desc->len)));

                if (!(desc->qid & 0x80))        /* reply to a command */
                        wpi_cmd_intr(sc, desc);

                switch (desc->type) {
                case WPI_RX_DONE:
                        /* a 802.11 frame was received */
                        wpi_rx_intr(sc, desc, data);
                        break;

                case WPI_TX_DONE:
                        /* a 802.11 frame has been transmitted */
                        wpi_tx_intr(sc, desc);
                        break;

                case WPI_UC_READY:
                {
                        struct wpi_ucode_info *uc =
                            (struct wpi_ucode_info *)(desc + 1);

                        /* the microcontroller is ready */
                        DPRINTF(("microcode alive notification version %x "
                            "alive %x\n", le32toh(uc->version),
                            le32toh(uc->valid)));

                        if (le32toh(uc->valid) != 1) {
                                aprint_error_dev(sc->sc_dev,
                                    "microcontroller initialization failed\n");
                        }
                        break;
                }
                case WPI_STATE_CHANGED:
                {
                        uint32_t *status = (uint32_t *)(desc + 1);

                        /* enabled/disabled notification */
                        DPRINTF(("state changed to %x\n", le32toh(*status)));

                        if (le32toh(*status) & 1) {
                                s = splnet();
                                /* the radio button has to be pushed */
                                /* wake up thread to signal powerd */
                                cv_signal(&sc->sc_rsw_cv);
                                aprint_error_dev(sc->sc_dev,
                                    "Radio transmitter is off\n");
                                /* turn the interface down */
                                ifp->if_flags &= ~IFF_UP;
                                wpi_stop_intr(ifp, 1);
                                splx(s);
                                return; /* no further processing */
                        }
                        break;
                }
                case WPI_START_SCAN:
                {
#if 0
                        struct wpi_start_scan *scan =
                            (struct wpi_start_scan *)(desc + 1);

                        DPRINTFN(2, ("scanning channel %d status %x\n",
                            scan->chan, le32toh(scan->status)));

                        /* fix current channel */
                        ic->ic_curchan = &ic->ic_channels[scan->chan];
#endif
                        break;
                }
                case WPI_STOP_SCAN:
                {
#ifdef WPI_DEBUG
                        struct wpi_stop_scan *scan =
                            (struct wpi_stop_scan *)(desc + 1);
#endif

                        DPRINTF(("scan finished nchan=%d status=%d chan=%d\n",
                            scan->nchan, scan->status, scan->chan));

                        s = splnet();
                        sc->is_scanning = false;
                        if (ic->ic_state == IEEE80211_S_SCAN)
                                ieee80211_next_scan(ic);
                        splx(s);
                        break;
                }
                }

                sc->rxq.cur = (sc->rxq.cur + 1) % WPI_RX_RING_COUNT;
        }

        /* tell the firmware what we have processed */
        hw = (hw == 0) ? WPI_RX_RING_COUNT - 1 : hw - 1;
        WPI_WRITE(sc, WPI_RX_WIDX, hw & ~7);
}

static int
wpi_intr(void *arg)
{
        struct wpi_softc *sc = arg;
        uint32_t r;

        r = WPI_READ(sc, WPI_INTR);
        if (r == 0 || r == 0xffffffff)
                return 0;       /* not for us */

        DPRINTFN(6, ("interrupt reg %x\n", r));

        /* disable interrupts */
        WPI_WRITE(sc, WPI_MASK, 0);

        softint_schedule(sc->sc_soft_ih);
        return 1;
}

static void
wpi_softintr(void *arg)
{
        struct wpi_softc *sc = arg;
        struct ifnet *ifp = sc->sc_ic.ic_ifp;
        uint32_t r;

        r = WPI_READ(sc, WPI_INTR);
        if (r == 0 || r == 0xffffffff)
                goto out;

        /* ack interrupts */
        WPI_WRITE(sc, WPI_INTR, r);

        if (r & (WPI_SW_ERROR | WPI_HW_ERROR)) {
                /* SYSTEM FAILURE, SYSTEM FAILURE */
                aprint_error_dev(sc->sc_dev, "fatal firmware error\n");
                ifp->if_flags &= ~IFF_UP;
                wpi_stop_intr(ifp, 1);
                return;
        }

        if (r & WPI_RX_INTR)
                wpi_notif_intr(sc);

        if (r & WPI_ALIVE_INTR) /* firmware initialized */
                wakeup(sc);

 out:
        /* re-enable interrupts */
        if (ifp->if_flags & IFF_UP)
                WPI_WRITE(sc, WPI_MASK, WPI_INTR_MASK);
}

static uint8_t
wpi_plcp_signal(int rate)
{
        switch (rate) {
        /* CCK rates (returned values are device-dependent) */
        case 2:         return 10;
        case 4:         return 20;
        case 11:        return 55;
        case 22:        return 110;

        /* OFDM rates (cf IEEE Std 802.11a-1999, pp. 14 Table 80) */
        /* R1-R4, (u)ral is R4-R1 */
        case 12:        return 0xd;
        case 18:        return 0xf;
        case 24:        return 0x5;
        case 36:        return 0x7;
        case 48:        return 0x9;
        case 72:        return 0xb;
        case 96:        return 0x1;
        case 108:       return 0x3;

        /* unsupported rates (should not get there) */
        default:        return 0;
        }
}

/* quickly determine if a given rate is CCK or OFDM */
#define WPI_RATE_IS_OFDM(rate) ((rate) >= 12 && (rate) != 22)

static int
wpi_tx_data(struct wpi_softc *sc, struct mbuf *m0, struct ieee80211_node *ni,
    int ac)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_tx_ring *ring = &sc->txq[ac];
        struct wpi_tx_desc *desc;
        struct wpi_tx_data *data;
        struct wpi_tx_cmd *cmd;
        struct wpi_cmd_data *tx;
        struct ieee80211_frame *wh;
        struct ieee80211_key *k;
        const struct chanAccParams *cap;
        struct mbuf *mnew;
        int i, rate, error, hdrlen, noack = 0;

        desc = &ring->desc[ring->cur];
        data = &ring->data[ring->cur];

        wh = mtod(m0, struct ieee80211_frame *);

        if (ieee80211_has_qos(wh)) {
                cap = &ic->ic_wme.wme_chanParams;
                noack = cap->cap_wmeParams[ac].wmep_noackPolicy;
        }

        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 *);
        }

        hdrlen = ieee80211_anyhdrsize(wh);

        /* pickup a rate */
        if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) ==
            IEEE80211_FC0_TYPE_MGT) {
                /* mgmt frames are sent at the lowest available bit-rate */
                rate = ni->ni_rates.rs_rates[0];
        } else {
                if (ic->ic_fixed_rate != -1) {
                        rate = ic->ic_sup_rates[ic->ic_curmode].
                            rs_rates[ic->ic_fixed_rate];
                } else
                        rate = ni->ni_rates.rs_rates[ni->ni_txrate];
        }
        rate &= IEEE80211_RATE_VAL;

        if (sc->sc_drvbpf != NULL) {
                struct wpi_tx_radiotap_header *tap = &sc->sc_txtap;

                tap->wt_flags = 0;
                tap->wt_chan_freq = htole16(ni->ni_chan->ic_freq);
                tap->wt_chan_flags = htole16(ni->ni_chan->ic_flags);
                tap->wt_rate = rate;
                tap->wt_hwqueue = ac;
                if (wh->i_fc[1] & IEEE80211_FC1_WEP)
                        tap->wt_flags |= IEEE80211_RADIOTAP_F_WEP;

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

        cmd = &ring->cmd[ring->cur];
        cmd->code = WPI_CMD_TX_DATA;
        cmd->flags = 0;
        cmd->qid = ring->qid;
        cmd->idx = ring->cur;

        tx = (struct wpi_cmd_data *)cmd->data;
        /* no need to zero tx, all fields are reinitialized here */
        tx->flags = 0;

        if (!noack && !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
                tx->flags |= htole32(WPI_TX_NEED_ACK);
        } else if (m0->m_pkthdr.len + IEEE80211_CRC_LEN > ic->ic_rtsthreshold)
                tx->flags |= htole32(WPI_TX_NEED_RTS | WPI_TX_FULL_TXOP);

        tx->flags |= htole32(WPI_TX_AUTO_SEQ);

        /* retrieve destination node's id */
        tx->id = IEEE80211_IS_MULTICAST(wh->i_addr1) ? WPI_ID_BROADCAST :
                WPI_ID_BSS;

        if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) ==
            IEEE80211_FC0_TYPE_MGT) {
                /* tell h/w to set timestamp in probe responses */
                if ((wh->i_fc[0] &
                    (IEEE80211_FC0_TYPE_MASK | IEEE80211_FC0_SUBTYPE_MASK)) ==
                    (IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_RESP))
                        tx->flags |= htole32(WPI_TX_INSERT_TSTAMP);

                if (((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) ==
                         IEEE80211_FC0_SUBTYPE_ASSOC_REQ) ||
                        ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) ==
                         IEEE80211_FC0_SUBTYPE_REASSOC_REQ))
                        tx->timeout = htole16(3);
                else
                        tx->timeout = htole16(2);
        } else
                tx->timeout = htole16(0);

        tx->rate = wpi_plcp_signal(rate);

        /* be very persistent at sending frames out */
        tx->rts_ntries = 7;
        tx->data_ntries = 15;

        tx->ofdm_mask = 0xff;
        tx->cck_mask = 0x0f;
        tx->lifetime = htole32(WPI_LIFETIME_INFINITE);

        tx->len = htole16(m0->m_pkthdr.len);

        /* save and trim IEEE802.11 header */
        memcpy((uint8_t *)(tx + 1), wh, hdrlen);
        m_adj(m0, hdrlen);

        error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m0,
            BUS_DMA_WRITE | BUS_DMA_NOWAIT);
        if (error != 0 && error != EFBIG) {
                aprint_error_dev(sc->sc_dev, "could not map mbuf (error %d)\n",
                    error);
                m_freem(m0);
                return error;
        }
        if (error != 0) {
                /* too many fragments, linearize */

                MGETHDR(mnew, M_DONTWAIT, MT_DATA);
                if (mnew == NULL) {
                        m_freem(m0);
                        return ENOMEM;
                }
                m_copy_pkthdr(mnew, m0);
                if (m0->m_pkthdr.len > MHLEN) {
                        MCLGET(mnew, M_DONTWAIT);
                        if (!(mnew->m_flags & M_EXT)) {
                                m_freem(m0);
                                m_freem(mnew);
                                return ENOMEM;
                        }
                }

                m_copydata(m0, 0, m0->m_pkthdr.len, mtod(mnew, void *));
                m_freem(m0);
                mnew->m_len = mnew->m_pkthdr.len;
                m0 = mnew;

                error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m0,
                    BUS_DMA_WRITE | BUS_DMA_NOWAIT);
                if (error != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "could not map mbuf (error %d)\n", error);
                        m_freem(m0);
                        return error;
                }
        }

        data->m = m0;
        data->ni = ni;

        DPRINTFN(4, ("sending data: qid=%d idx=%d len=%d nsegs=%d\n",
            ring->qid, ring->cur, m0->m_pkthdr.len, data->map->dm_nsegs));

        /* first scatter/gather segment is used by the tx data command */
        desc->flags = htole32(WPI_PAD32(m0->m_pkthdr.len) << 28 |
            (1 + data->map->dm_nsegs) << 24);
        desc->segs[0].addr = htole32(ring->cmd_dma.paddr +
            ring->cur * sizeof (struct wpi_tx_cmd));
        desc->segs[0].len  = htole32(4 + sizeof (struct wpi_cmd_data) +
            ((hdrlen + 3) & ~3));
        for (i = 1; i <= data->map->dm_nsegs; i++) {
                desc->segs[i].addr =
                    htole32(data->map->dm_segs[i - 1].ds_addr);
                desc->segs[i].len  =
                    htole32(data->map->dm_segs[i - 1].ds_len);
        }

        ring->queued++;

        bus_dmamap_sync(sc->sc_dmat, data->map, 0,
            data->map->dm_mapsize,
            BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->sc_dmat, ring->cmd_dma.map, 0,
            ring->cmd_dma.size,
            BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map, 0,
            ring->desc_dma.size,
            BUS_DMASYNC_PREWRITE);

        /* kick ring */
        ring->cur = (ring->cur + 1) % WPI_TX_RING_COUNT;
        WPI_WRITE(sc, WPI_TX_WIDX, ring->qid << 8 | ring->cur);

        return 0;
}

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

        /*
         * net80211 may still try to send management frames even if the
         * IFF_RUNNING flag is not set...
         */
        if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
                return;

        for (;;) {
                IF_DEQUEUE(&ic->ic_mgtq, m0);
                if (m0 != NULL) {

                        ni = M_GETCTX(m0, struct ieee80211_node *);
                        M_CLEARCTX(m0);

                        /* management frames go into ring 0 */
                        if (sc->txq[0].queued > sc->txq[0].count - 8) {
                                if_statinc(ifp, if_oerrors);
                                continue;
                        }
                        bpf_mtap3(ic->ic_rawbpf, m0, BPF_D_OUT);
                        if (wpi_tx_data(sc, m0, ni, 0) != 0) {
                                if_statinc(ifp, if_oerrors);
                                break;
                        }
                } else {
                        if (ic->ic_state != IEEE80211_S_RUN)
                                break;
                        IFQ_POLL(&ifp->if_snd, m0);
                        if (m0 == NULL)
                                break;

                        if (m0->m_len < sizeof (*eh) &&
                            (m0 = m_pullup(m0, sizeof (*eh))) == NULL) {
                                if_statinc(ifp, if_oerrors);
                                continue;
                        }
                        eh = mtod(m0, struct ether_header *);
                        ni = ieee80211_find_txnode(ic, eh->ether_dhost);
                        if (ni == NULL) {
                                m_freem(m0);
                                if_statinc(ifp, if_oerrors);
                                continue;
                        }

                        /* classify mbuf so we can find which tx ring to use */
                        if (ieee80211_classify(ic, m0, ni) != 0) {
                                m_freem(m0);
                                ieee80211_free_node(ni);
                                if_statinc(ifp, if_oerrors);
                                continue;
                        }

                        /* no QoS encapsulation for EAPOL frames */
                        ac = (eh->ether_type != htons(ETHERTYPE_PAE)) ?
                            M_WME_GETAC(m0) : WME_AC_BE;

                        if (sc->txq[ac].queued > sc->txq[ac].count - 8) {
                                /* there is no place left in this ring */
                                ifp->if_flags |= IFF_OACTIVE;
                                break;
                        }
                        IFQ_DEQUEUE(&ifp->if_snd, m0);
                        bpf_mtap(ifp, m0, BPF_D_OUT);
                        m0 = ieee80211_encap(ic, m0, ni);
                        if (m0 == NULL) {
                                ieee80211_free_node(ni);
                                if_statinc(ifp, if_oerrors);
                                continue;
                        }
                        bpf_mtap3(ic->ic_rawbpf, m0, BPF_D_OUT);
                        if (wpi_tx_data(sc, m0, ni, ac) != 0) {
                                ieee80211_free_node(ni);
                                if_statinc(ifp, if_oerrors);
                                break;
                        }
                }

                sc->sc_tx_timer = 5;
                ifp->if_timer = 1;
        }
}

static void
wpi_watchdog(struct ifnet *ifp)
{
        struct wpi_softc *sc = ifp->if_softc;

        ifp->if_timer = 0;

        if (sc->sc_tx_timer > 0) {
                if (--sc->sc_tx_timer == 0) {
                        aprint_error_dev(sc->sc_dev, "device timeout\n");
                        ifp->if_flags &= ~IFF_UP;
                        wpi_stop_intr(ifp, 1);
                        if_statinc(ifp, if_oerrors);
                        return;
                }
                ifp->if_timer = 1;
        }

        ieee80211_watchdog(&sc->sc_ic);
}

static int
wpi_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
#define IS_RUNNING(ifp) \
        ((ifp->if_flags & IFF_UP) && (ifp->if_flags & IFF_RUNNING))

        struct wpi_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        int s, error = 0;

        s = splnet();

        switch (cmd) {
        case SIOCSIFFLAGS:
                if ((error = ifioctl_common(ifp, cmd, data)) != 0)
                        break;
                if (ifp->if_flags & IFF_UP) {
                        if (!(ifp->if_flags & IFF_RUNNING))
                                wpi_init(ifp);
                } else {
                        if (ifp->if_flags & IFF_RUNNING)
                                wpi_stop(ifp, 1);
                }
                break;

        case SIOCADDMULTI:
        case SIOCDELMULTI:
                /* XXX no h/w multicast filter? --dyoung */
                if ((error = ether_ioctl(ifp, cmd, data)) == ENETRESET) {
                        /* setup multicast filter, etc */
                        error = 0;
                }
                break;

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

        if (error == ENETRESET) {
                if (IS_RUNNING(ifp) &&
                        (ic->ic_roaming != IEEE80211_ROAMING_MANUAL))
                        wpi_init(ifp);
                error = 0;
        }

        splx(s);
        return error;

#undef IS_RUNNING
}

/*
 * Extract various information from EEPROM.
 */
static void
wpi_read_eeprom(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        char domain[4];
        int i;

        wpi_read_prom_data(sc, WPI_EEPROM_CAPABILITIES, &sc->cap, 1);
        wpi_read_prom_data(sc, WPI_EEPROM_REVISION, &sc->rev, 2);
        wpi_read_prom_data(sc, WPI_EEPROM_TYPE, &sc->type, 1);

        DPRINTF(("cap=%x rev=%x type=%x\n", sc->cap, le16toh(sc->rev),
            sc->type));

        /* read and print regulatory domain */
        wpi_read_prom_data(sc, WPI_EEPROM_DOMAIN, domain, 4);
        aprint_normal_dev(sc->sc_dev, "%.4s", domain);

        /* read and print MAC address */
        wpi_read_prom_data(sc, WPI_EEPROM_MAC, ic->ic_myaddr, 6);
        aprint_normal(", address %s\n", ether_sprintf(ic->ic_myaddr));

        /* read the list of authorized channels */
        for (i = 0; i < WPI_CHAN_BANDS_COUNT; i++)
                wpi_read_eeprom_channels(sc, i);

        /* read the list of power groups */
        for (i = 0; i < WPI_POWER_GROUPS_COUNT; i++)
                wpi_read_eeprom_group(sc, i);
}

static void
wpi_read_eeprom_channels(struct wpi_softc *sc, int n)
{
        struct ieee80211com *ic = &sc->sc_ic;
        const struct wpi_chan_band *band = &wpi_bands[n];
        struct wpi_eeprom_chan channels[WPI_MAX_CHAN_PER_BAND];
        int chan, i;

        wpi_read_prom_data(sc, band->addr, channels,
            band->nchan * sizeof (struct wpi_eeprom_chan));

        for (i = 0; i < band->nchan; i++) {
                if (!(channels[i].flags & WPI_EEPROM_CHAN_VALID))
                        continue;

                chan = band->chan[i];

                if (n == 0) {   /* 2GHz band */
                        ic->ic_channels[chan].ic_freq =
                            ieee80211_ieee2mhz(chan, IEEE80211_CHAN_2GHZ);
                        ic->ic_channels[chan].ic_flags =
                            IEEE80211_CHAN_CCK | IEEE80211_CHAN_OFDM |
                            IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;

                } else {        /* 5GHz band */
                        /*
                         * Some 3945ABG adapters support channels 7, 8, 11
                         * and 12 in the 2GHz *and* 5GHz bands.
                         * Because of limitations in our net80211(9) stack,
                         * we can't support these channels in 5GHz band.
                         */
                        if (chan <= 14)
                                continue;

                        ic->ic_channels[chan].ic_freq =
                            ieee80211_ieee2mhz(chan, IEEE80211_CHAN_5GHZ);
                        ic->ic_channels[chan].ic_flags = IEEE80211_CHAN_A;
                }

                /* is active scan allowed on this channel? */
                if (!(channels[i].flags & WPI_EEPROM_CHAN_ACTIVE)) {
                        ic->ic_channels[chan].ic_flags |=
                            IEEE80211_CHAN_PASSIVE;
                }

                /* save maximum allowed power for this channel */
                sc->maxpwr[chan] = channels[i].maxpwr;

                DPRINTF(("adding chan %d flags=0x%x maxpwr=%d\n",
                    chan, channels[i].flags, sc->maxpwr[chan]));
        }
}

static void
wpi_read_eeprom_group(struct wpi_softc *sc, int n)
{
        struct wpi_power_group *group = &sc->groups[n];
        struct wpi_eeprom_group rgroup;
        int i;

        wpi_read_prom_data(sc, WPI_EEPROM_POWER_GRP + n * 32, &rgroup,
            sizeof rgroup);

        /* save power group information */
        group->chan   = rgroup.chan;
        group->maxpwr = rgroup.maxpwr;
        /* temperature at which the samples were taken */
        group->temp   = (int16_t)le16toh(rgroup.temp);

        DPRINTF(("power group %d: chan=%d maxpwr=%d temp=%d\n", n,
            group->chan, group->maxpwr, group->temp));

        for (i = 0; i < WPI_SAMPLES_COUNT; i++) {
                group->samples[i].index = rgroup.samples[i].index;
                group->samples[i].power = rgroup.samples[i].power;

                DPRINTF(("\tsample %d: index=%d power=%d\n", i,
                    group->samples[i].index, group->samples[i].power));
        }
}

/*
 * Send a command to the firmware.
 */
static int
wpi_cmd(struct wpi_softc *sc, int code, const void *buf, int size, int async)
{
        struct wpi_tx_ring *ring = &sc->cmdq;
        struct wpi_tx_desc *desc;
        struct wpi_tx_cmd *cmd;
        struct wpi_dma_info *dma;

        KASSERT(size <= sizeof cmd->data);

        desc = &ring->desc[ring->cur];
        cmd = &ring->cmd[ring->cur];

        cmd->code = code;
        cmd->flags = 0;
        cmd->qid = ring->qid;
        cmd->idx = ring->cur;
        memcpy(cmd->data, buf, size);

        dma = &ring->cmd_dma;
        bus_dmamap_sync(dma->tag, dma->map, 0, dma->size, BUS_DMASYNC_PREWRITE);

        desc->flags = htole32(WPI_PAD32(size) << 28 | 1 << 24);
        desc->segs[0].addr = htole32(ring->cmd_dma.paddr +
            ring->cur * sizeof (struct wpi_tx_cmd));
        desc->segs[0].len  = htole32(4 + size);

        dma = &ring->desc_dma;
        bus_dmamap_sync(dma->tag, dma->map, 0, dma->size, BUS_DMASYNC_PREWRITE);

        /* kick cmd ring */
        ring->cur = (ring->cur + 1) % WPI_CMD_RING_COUNT;
        WPI_WRITE(sc, WPI_TX_WIDX, ring->qid << 8 | ring->cur);

        return async ? 0 : tsleep(cmd, PCATCH, "wpicmd", hz);
}

static int
wpi_wme_update(struct ieee80211com *ic)
{
#define WPI_EXP2(v)     htole16((1 << (v)) - 1)
#define WPI_USEC(v)     htole16(IEEE80211_TXOP_TO_US(v))
        struct wpi_softc *sc = ic->ic_ifp->if_softc;
        const struct wmeParams *wmep;
        struct wpi_wme_setup wme;
        int ac;

        /* don't override default WME values if WME is not actually enabled */
        if (!(ic->ic_flags & IEEE80211_F_WME))
                return 0;

        wme.flags = 0;
        for (ac = 0; ac < WME_NUM_AC; ac++) {
                wmep = &ic->ic_wme.wme_chanParams.cap_wmeParams[ac];
                wme.ac[ac].aifsn = wmep->wmep_aifsn;
                wme.ac[ac].cwmin = WPI_EXP2(wmep->wmep_logcwmin);
                wme.ac[ac].cwmax = WPI_EXP2(wmep->wmep_logcwmax);
                wme.ac[ac].txop  = WPI_USEC(wmep->wmep_txopLimit);

                DPRINTF(("setting WME for queue %d aifsn=%d cwmin=%d cwmax=%d "
                    "txop=%d\n", ac, wme.ac[ac].aifsn, wme.ac[ac].cwmin,
                    wme.ac[ac].cwmax, wme.ac[ac].txop));
        }

        return wpi_cmd(sc, WPI_CMD_SET_WME, &wme, sizeof wme, 1);
#undef WPI_USEC
#undef WPI_EXP2
}

/*
 * Configure h/w multi-rate retries.
 */
static int
wpi_mrr_setup(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_mrr_setup mrr;
        int i, error;

        /* CCK rates (not used with 802.11a) */
        for (i = WPI_CCK1; i <= WPI_CCK11; i++) {
                mrr.rates[i].flags = 0;
                mrr.rates[i].plcp = wpi_ridx_to_plcp[i];
                /* fallback to the immediate lower CCK rate (if any) */
                mrr.rates[i].next = (i == WPI_CCK1) ? WPI_CCK1 : i - 1;
                /* try one time at this rate before falling back to "next" */
                mrr.rates[i].ntries = 1;
        }

        /* OFDM rates (not used with 802.11b) */
        for (i = WPI_OFDM6; i <= WPI_OFDM54; i++) {
                mrr.rates[i].flags = 0;
                mrr.rates[i].plcp = wpi_ridx_to_plcp[i];
                /* fallback to the immediate lower rate (if any) */
                /* we allow fallback from OFDM/6 to CCK/2 in 11b/g mode */
                mrr.rates[i].next = (i == WPI_OFDM6) ?
                    ((ic->ic_curmode == IEEE80211_MODE_11A) ?
                        WPI_OFDM6 : WPI_CCK2) :
                    i - 1;
                /* try one time at this rate before falling back to "next" */
                mrr.rates[i].ntries = 1;
        }

        /* setup MRR for control frames */
        mrr.which = htole32(WPI_MRR_CTL);
        error = wpi_cmd(sc, WPI_CMD_MRR_SETUP, &mrr, sizeof mrr, 0);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not setup MRR for control frames\n");
                return error;
        }

        /* setup MRR for data frames */
        mrr.which = htole32(WPI_MRR_DATA);
        error = wpi_cmd(sc, WPI_CMD_MRR_SETUP, &mrr, sizeof mrr, 0);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not setup MRR for data frames\n");
                return error;
        }

        return 0;
}

static void
wpi_set_led(struct wpi_softc *sc, uint8_t which, uint8_t off, uint8_t on)
{
        struct wpi_cmd_led led;

        led.which = which;
        led.unit = htole32(100000);     /* on/off in unit of 100ms */
        led.off = off;
        led.on = on;

        (void)wpi_cmd(sc, WPI_CMD_SET_LED, &led, sizeof led, 1);
}

static void
wpi_enable_tsf(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct wpi_cmd_tsf tsf;
        uint64_t val, mod;

        memset(&tsf, 0, sizeof tsf);
        memcpy(&tsf.tstamp, ni->ni_tstamp.data, sizeof (uint64_t));
        tsf.bintval = htole16(ni->ni_intval);
        tsf.lintval = htole16(10);

        /* compute remaining time until next beacon */
        val = (uint64_t)ni->ni_intval * 1024;   /* msecs -> usecs */
        mod = le64toh(tsf.tstamp) % val;
        tsf.binitval = htole32((uint32_t)(val - mod));

        DPRINTF(("TSF bintval=%u tstamp=%" PRIu64 ", init=%u\n",
            ni->ni_intval, le64toh(tsf.tstamp), (uint32_t)(val - mod)));

        if (wpi_cmd(sc, WPI_CMD_TSF, &tsf, sizeof tsf, 1) != 0)
                aprint_error_dev(sc->sc_dev, "could not enable TSF\n");
}

/*
 * Update Tx power to match what is defined for channel `c'.
 */
static int
wpi_set_txpower(struct wpi_softc *sc, struct ieee80211_channel *c, int async)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_power_group *group;
        struct wpi_cmd_txpower txpower;
        u_int chan;
        int i;

        /* get channel number */
        chan = ieee80211_chan2ieee(ic, c);

        /* find the power group to which this channel belongs */
        if (IEEE80211_IS_CHAN_5GHZ(c)) {
                for (group = &sc->groups[1]; group < &sc->groups[4]; group++)
                        if (chan <= group->chan)
                                break;
        } else
                group = &sc->groups[0];

        memset(&txpower, 0, sizeof txpower);
        txpower.band = IEEE80211_IS_CHAN_5GHZ(c) ? 0 : 1;
        txpower.chan = htole16(chan);

        /* set Tx power for all OFDM and CCK rates */
        for (i = 0; i <= 11 ; i++) {
                /* retrieve Tx power for this channel/rate combination */
                int idx = wpi_get_power_index(sc, group, c,
                    wpi_ridx_to_rate[i]);

                txpower.rates[i].plcp = wpi_ridx_to_plcp[i];

                if (IEEE80211_IS_CHAN_5GHZ(c)) {
                        txpower.rates[i].rf_gain = wpi_rf_gain_5ghz[idx];
                        txpower.rates[i].dsp_gain = wpi_dsp_gain_5ghz[idx];
                } else {
                        txpower.rates[i].rf_gain = wpi_rf_gain_2ghz[idx];
                        txpower.rates[i].dsp_gain = wpi_dsp_gain_2ghz[idx];
                }
                DPRINTF(("chan %d/rate %d: power index %d\n", chan,
                    wpi_ridx_to_rate[i], idx));
        }

        return wpi_cmd(sc, WPI_CMD_TXPOWER, &txpower, sizeof txpower, async);
}

/*
 * Determine Tx power index for a given channel/rate combination.
 * This takes into account the regulatory information from EEPROM and the
 * current temperature.
 */
static int
wpi_get_power_index(struct wpi_softc *sc, struct wpi_power_group *group,
    struct ieee80211_channel *c, int rate)
{
/* fixed-point arithmetic division using a n-bit fractional part */
#define fdivround(a, b, n)      \
        ((((1 << n) * (a)) / (b) + (1 << n) / 2) / (1 << n))

/* linear interpolation */
#define interpolate(x, x1, y1, x2, y2, n)       \
        ((y1) + fdivround(((x) - (x1)) * ((y2) - (y1)), (x2) - (x1), n))

        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_power_sample *sample;
        int pwr, idx;
        u_int chan;

        /* get channel number */
        chan = ieee80211_chan2ieee(ic, c);

        /* default power is group's maximum power - 3dB */
        pwr = group->maxpwr / 2;

        /* decrease power for highest OFDM rates to reduce distortion */
        switch (rate) {
        case 72:        /* 36Mb/s */
                pwr -= IEEE80211_IS_CHAN_2GHZ(c) ? 0 :  5;
                break;
        case 96:        /* 48Mb/s */
                pwr -= IEEE80211_IS_CHAN_2GHZ(c) ? 7 : 10;
                break;
        case 108:       /* 54Mb/s */
                pwr -= IEEE80211_IS_CHAN_2GHZ(c) ? 9 : 12;
                break;
        }

        /* never exceed channel's maximum allowed Tx power */
        pwr = uimin(pwr, sc->maxpwr[chan]);

        /* retrieve power index into gain tables from samples */
        for (sample = group->samples; sample < &group->samples[3]; sample++)
                if (pwr > sample[1].power)
                        break;
        /* fixed-point linear interpolation using a 19-bit fractional part */
        idx = interpolate(pwr, sample[0].power, sample[0].index,
            sample[1].power, sample[1].index, 19);

        /*-
         * Adjust power index based on current temperature:
         * - if cooler than factory-calibrated: decrease output power
         * - if warmer than factory-calibrated: increase output power
         */
        idx -= (sc->temp - group->temp) * 11 / 100;

        /* decrease power for CCK rates (-5dB) */
        if (!WPI_RATE_IS_OFDM(rate))
                idx += 10;

        /* keep power index in a valid range */
        if (idx < 0)
                return 0;
        if (idx > WPI_MAX_PWR_INDEX)
                return WPI_MAX_PWR_INDEX;
        return idx;

#undef interpolate
#undef fdivround
}

/*
 * Build a beacon frame that the firmware will broadcast periodically in
 * IBSS or HostAP modes.
 */
static int
wpi_setup_beacon(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_tx_ring *ring = &sc->cmdq;
        struct wpi_tx_desc *desc;
        struct wpi_tx_data *data;
        struct wpi_tx_cmd *cmd;
        struct wpi_cmd_beacon *bcn;
        struct ieee80211_beacon_offsets bo;
        struct mbuf *m0;
        int error;

        desc = &ring->desc[ring->cur];
        data = &ring->data[ring->cur];

        m0 = ieee80211_beacon_alloc(ic, ni, &bo);
        if (m0 == NULL) {
                aprint_error_dev(sc->sc_dev,
                    "could not allocate beacon frame\n");
                return ENOMEM;
        }

        cmd = &ring->cmd[ring->cur];
        cmd->code = WPI_CMD_SET_BEACON;
        cmd->flags = 0;
        cmd->qid = ring->qid;
        cmd->idx = ring->cur;

        bcn = (struct wpi_cmd_beacon *)cmd->data;
        memset(bcn, 0, sizeof (struct wpi_cmd_beacon));
        bcn->id = WPI_ID_BROADCAST;
        bcn->ofdm_mask = 0xff;
        bcn->cck_mask = 0x0f;
        bcn->lifetime = htole32(WPI_LIFETIME_INFINITE);
        bcn->len = htole16(m0->m_pkthdr.len);
        bcn->rate = (ic->ic_curmode == IEEE80211_MODE_11A) ?
            wpi_plcp_signal(12) : wpi_plcp_signal(2);
        bcn->flags = htole32(WPI_TX_AUTO_SEQ | WPI_TX_INSERT_TSTAMP);

        /* save and trim IEEE802.11 header */
        m_copydata(m0, 0, sizeof (struct ieee80211_frame), (void *)&bcn->wh);
        m_adj(m0, sizeof (struct ieee80211_frame));

        /* assume beacon frame is contiguous */
        error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m0,
            BUS_DMA_READ | BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not map beacon\n");
                m_freem(m0);
                return error;
        }

        data->m = m0;

        /* first scatter/gather segment is used by the beacon command */
        desc->flags = htole32(WPI_PAD32(m0->m_pkthdr.len) << 28 | 2 << 24);
        desc->segs[0].addr = htole32(ring->cmd_dma.paddr +
            ring->cur * sizeof (struct wpi_tx_cmd));
        desc->segs[0].len  = htole32(4 + sizeof (struct wpi_cmd_beacon));
        desc->segs[1].addr = htole32(data->map->dm_segs[0].ds_addr);
        desc->segs[1].len  = htole32(data->map->dm_segs[0].ds_len);

        bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map, 0,
            ring->desc_dma.map->dm_mapsize, BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
            BUS_DMASYNC_PREWRITE);

        /* kick cmd ring */
        ring->cur = (ring->cur + 1) % WPI_CMD_RING_COUNT;
        WPI_WRITE(sc, WPI_TX_WIDX, ring->qid << 8 | ring->cur);

        return 0;
}

static int
wpi_auth(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211_node *ni = ic->ic_bss;
        struct wpi_node_info node;
        int error;

        /* update adapter's configuration */
        IEEE80211_ADDR_COPY(sc->config.bssid, ni->ni_bssid);
        sc->config.chan = ieee80211_chan2ieee(ic, ni->ni_chan);
        sc->config.flags = htole32(WPI_CONFIG_TSF);
        if (IEEE80211_IS_CHAN_2GHZ(ni->ni_chan)) {
                sc->config.flags |= htole32(WPI_CONFIG_AUTO |
                    WPI_CONFIG_24GHZ);
        }
        switch (ic->ic_curmode) {
        case IEEE80211_MODE_11A:
                sc->config.cck_mask  = 0;
                sc->config.ofdm_mask = 0x15;
                break;
        case IEEE80211_MODE_11B:
                sc->config.cck_mask  = 0x03;
                sc->config.ofdm_mask = 0;
                break;
        default:        /* assume 802.11b/g */
                sc->config.cck_mask  = 0x0f;
                sc->config.ofdm_mask = 0x15;
        }
        DPRINTF(("config chan %d flags %x cck %x ofdm %x\n", sc->config.chan,
            sc->config.flags, sc->config.cck_mask, sc->config.ofdm_mask));
        error = wpi_cmd(sc, WPI_CMD_CONFIGURE, &sc->config,
            sizeof (struct wpi_config), 1);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not configure\n");
                return error;
        }

        /* configuration has changed, set Tx power accordingly */
        if ((error = wpi_set_txpower(sc, ni->ni_chan, 1)) != 0) {
                aprint_error_dev(sc->sc_dev, "could not set Tx power\n");
                return error;
        }

        /* add default node */
        memset(&node, 0, sizeof node);
        IEEE80211_ADDR_COPY(node.bssid, ni->ni_bssid);
        node.id = WPI_ID_BSS;
        node.rate = (ic->ic_curmode == IEEE80211_MODE_11A) ?
            wpi_plcp_signal(12) : wpi_plcp_signal(2);
        node.action = htole32(WPI_ACTION_SET_RATE);
        node.antenna = WPI_ANTENNA_BOTH;
        error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not add BSS node\n");
                return error;
        }

        return 0;
}

/*
 * Send a scan request to the firmware.  Since this command is huge, we map it
 * into a mbuf instead of using the pre-allocated set of commands.
 */
static int
wpi_scan(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_tx_ring *ring = &sc->cmdq;
        struct wpi_tx_desc *desc;
        struct wpi_tx_data *data;
        struct wpi_tx_cmd *cmd;
        struct wpi_scan_hdr *hdr;
        struct wpi_scan_chan *chan;
        struct ieee80211_frame *wh;
        struct ieee80211_rateset *rs;
        struct ieee80211_channel *c;
        uint8_t *frm;
        int pktlen, error, nrates;

        if (ic->ic_curchan == NULL)
                return EIO;

        desc = &ring->desc[ring->cur];
        data = &ring->data[ring->cur];

        MGETHDR(data->m, M_DONTWAIT, MT_DATA);
        if (data->m == NULL) {
                aprint_error_dev(sc->sc_dev,
                    "could not allocate mbuf for scan command\n");
                return ENOMEM;
        }
        MCLGET(data->m, M_DONTWAIT);
        if (!(data->m->m_flags & M_EXT)) {
                m_freem(data->m);
                data->m = NULL;
                aprint_error_dev(sc->sc_dev,
                    "could not allocate mbuf for scan command\n");
                return ENOMEM;
        }

        cmd = mtod(data->m, struct wpi_tx_cmd *);
        cmd->code = WPI_CMD_SCAN;
        cmd->flags = 0;
        cmd->qid = ring->qid;
        cmd->idx = ring->cur;

        hdr = (struct wpi_scan_hdr *)cmd->data;
        memset(hdr, 0, sizeof (struct wpi_scan_hdr));
        hdr->cmd.flags = htole32(WPI_TX_AUTO_SEQ);
        hdr->cmd.id = WPI_ID_BROADCAST;
        hdr->cmd.lifetime = htole32(WPI_LIFETIME_INFINITE);
        /*
         * Move to the next channel if no packets are received within 5 msecs
         * after sending the probe request (this helps to reduce the duration
         * of active scans).
         */
        hdr->quiet = htole16(5);        /* timeout in milliseconds */
        hdr->plcp_threshold = htole16(1);       /* min # of packets */

        if (ic->ic_curchan->ic_flags & IEEE80211_CHAN_5GHZ) {
                hdr->crc_threshold = htole16(1);
                /* send probe requests at 6Mbps */
                hdr->cmd.rate = wpi_plcp_signal(12);
                rs = &ic->ic_sup_rates[IEEE80211_MODE_11A];
        } else {
                hdr->flags = htole32(WPI_CONFIG_24GHZ | WPI_CONFIG_AUTO);
                /* send probe requests at 1Mbps */
                hdr->cmd.rate = wpi_plcp_signal(2);
                rs = &ic->ic_sup_rates[IEEE80211_MODE_11G];
        }

        /* for directed scans, firmware inserts the essid IE itself */
        if (ic->ic_des_esslen != 0) {
                hdr->essid[0].id  = IEEE80211_ELEMID_SSID;
                hdr->essid[0].len = ic->ic_des_esslen;
                memcpy(hdr->essid[0].data, ic->ic_des_essid, ic->ic_des_esslen);
        }

        /*
         * Build a probe request frame.  Most of the following code is a
         * copy & paste of what is done in net80211.
         */
        wh = (struct ieee80211_frame *)(hdr + 1);
        wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
            IEEE80211_FC0_SUBTYPE_PROBE_REQ;
        wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
        IEEE80211_ADDR_COPY(wh->i_addr1, etherbroadcastaddr);
        IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
        IEEE80211_ADDR_COPY(wh->i_addr3, etherbroadcastaddr);
        *(u_int16_t *)&wh->i_dur[0] = 0;        /* filled by h/w */
        *(u_int16_t *)&wh->i_seq[0] = 0;        /* filled by h/w */

        frm = (uint8_t *)(wh + 1);

        /* add empty essid IE (firmware generates it for directed scans) */
        *frm++ = IEEE80211_ELEMID_SSID;
        *frm++ = 0;

        /* add supported rates IE */
        *frm++ = IEEE80211_ELEMID_RATES;
        nrates = rs->rs_nrates;
        if (nrates > IEEE80211_RATE_SIZE)
                nrates = IEEE80211_RATE_SIZE;
        *frm++ = nrates;
        memcpy(frm, rs->rs_rates, nrates);
        frm += nrates;

        /* add supported xrates IE */
        if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
                nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
                *frm++ = IEEE80211_ELEMID_XRATES;
                *frm++ = nrates;
                memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
                frm += nrates;
        }

        /* setup length of probe request */
        hdr->cmd.len = htole16(frm - (uint8_t *)wh);

        chan = (struct wpi_scan_chan *)frm;
        c = ic->ic_curchan;

        chan->chan = ieee80211_chan2ieee(ic, c);
        chan->flags = 0;
        if (!(c->ic_flags & IEEE80211_CHAN_PASSIVE)) {
                chan->flags |= WPI_CHAN_ACTIVE;
                if (ic->ic_des_esslen != 0)
                        chan->flags |= WPI_CHAN_DIRECT;
        }
        chan->dsp_gain = 0x6e;
        if (IEEE80211_IS_CHAN_5GHZ(c)) {
                chan->rf_gain = 0x3b;
                chan->active  = htole16(10);
                chan->passive = htole16(110);
        } else {
                chan->rf_gain = 0x28;
                chan->active  = htole16(20);
                chan->passive = htole16(120);
        }
        hdr->nchan++;
        chan++;

        frm += sizeof (struct wpi_scan_chan);

        hdr->len = htole16(frm - (uint8_t *)hdr);
        pktlen = frm - (uint8_t *)cmd;

        error = bus_dmamap_load(sc->sc_dmat, data->map, cmd, pktlen, NULL,
            BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not map scan command\n");
                m_freem(data->m);
                data->m = NULL;
                return error;
        }

        desc->flags = htole32(WPI_PAD32(pktlen) << 28 | 1 << 24);
        desc->segs[0].addr = htole32(data->map->dm_segs[0].ds_addr);
        desc->segs[0].len  = htole32(data->map->dm_segs[0].ds_len);

        bus_dmamap_sync(sc->sc_dmat, ring->desc_dma.map, 0,
            ring->desc_dma.map->dm_mapsize, BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
            BUS_DMASYNC_PREWRITE);

        /* kick cmd ring */
        ring->cur = (ring->cur + 1) % WPI_CMD_RING_COUNT;
        WPI_WRITE(sc, WPI_TX_WIDX, ring->qid << 8 | ring->cur);

        return 0;       /* will be notified async. of failure/success */
}

static int
wpi_config(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct wpi_power power;
        struct wpi_bluetooth bluetooth;
        struct wpi_node_info node;
        int error;

        memset(&power, 0, sizeof power);
        power.flags = htole32(WPI_POWER_CAM | 0x8);
        error = wpi_cmd(sc, WPI_CMD_SET_POWER_MODE, &power, sizeof power, 0);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not set power mode\n");
                return error;
        }

        /* configure bluetooth coexistence */
        memset(&bluetooth, 0, sizeof bluetooth);
        bluetooth.flags = 3;
        bluetooth.lead = 0xaa;
        bluetooth.kill = 1;
        error = wpi_cmd(sc, WPI_CMD_BLUETOOTH, &bluetooth, sizeof bluetooth,
            0);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev,
                        "could not configure bluetooth coexistence\n");
                return error;
        }

        /* configure adapter */
        memset(&sc->config, 0, sizeof (struct wpi_config));
        IEEE80211_ADDR_COPY(ic->ic_myaddr, CLLADDR(ifp->if_sadl));
        IEEE80211_ADDR_COPY(sc->config.myaddr, ic->ic_myaddr);
        /* set default channel */
        sc->config.chan = ieee80211_chan2ieee(ic, ic->ic_curchan);
        sc->config.flags = htole32(WPI_CONFIG_TSF);
        if (IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan)) {
                sc->config.flags |= htole32(WPI_CONFIG_AUTO |
                    WPI_CONFIG_24GHZ);
        }
        sc->config.filter = 0;
        switch (ic->ic_opmode) {
        case IEEE80211_M_STA:
                sc->config.mode = WPI_MODE_STA;
                sc->config.filter |= htole32(WPI_FILTER_MULTICAST);
                break;
        case IEEE80211_M_IBSS:
        case IEEE80211_M_AHDEMO:
                sc->config.mode = WPI_MODE_IBSS;
                break;
        case IEEE80211_M_HOSTAP:
                sc->config.mode = WPI_MODE_HOSTAP;
                break;
        case IEEE80211_M_MONITOR:
                sc->config.mode = WPI_MODE_MONITOR;
                sc->config.filter |= htole32(WPI_FILTER_MULTICAST |
                    WPI_FILTER_CTL | WPI_FILTER_PROMISC);
                break;
        }
        sc->config.cck_mask  = 0x0f;    /* not yet negotiated */
        sc->config.ofdm_mask = 0xff;    /* not yet negotiated */
        error = wpi_cmd(sc, WPI_CMD_CONFIGURE, &sc->config,
            sizeof (struct wpi_config), 0);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "configure command failed\n");
                return error;
        }

        /* configuration has changed, set Tx power accordingly */
        if ((error = wpi_set_txpower(sc, ic->ic_curchan, 0)) != 0) {
                aprint_error_dev(sc->sc_dev, "could not set Tx power\n");
                return error;
        }

        /* add broadcast node */
        memset(&node, 0, sizeof node);
        IEEE80211_ADDR_COPY(node.bssid, etherbroadcastaddr);
        node.id = WPI_ID_BROADCAST;
        node.rate = wpi_plcp_signal(2);
        node.action = htole32(WPI_ACTION_SET_RATE);
        node.antenna = WPI_ANTENNA_BOTH;
        error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 0);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not add broadcast node\n");
                return error;
        }

        if ((error = wpi_mrr_setup(sc)) != 0) {
                aprint_error_dev(sc->sc_dev, "could not setup MRR\n");
                return error;
        }

        return 0;
}

static void
wpi_stop_master(struct wpi_softc *sc)
{
        uint32_t tmp;
        int ntries;

        tmp = WPI_READ(sc, WPI_RESET);
        WPI_WRITE(sc, WPI_RESET, tmp | WPI_STOP_MASTER);

        tmp = WPI_READ(sc, WPI_GPIO_CTL);
        if ((tmp & WPI_GPIO_PWR_STATUS) == WPI_GPIO_PWR_SLEEP)
                return; /* already asleep */

        for (ntries = 0; ntries < 100; ntries++) {
                if (WPI_READ(sc, WPI_RESET) & WPI_MASTER_DISABLED)
                        break;
                DELAY(10);
        }
        if (ntries == 100) {
                aprint_error_dev(sc->sc_dev, "timeout waiting for master\n");
        }
}

static int
wpi_power_up(struct wpi_softc *sc)
{
        uint32_t tmp;
        int ntries;

        wpi_mem_lock(sc);
        tmp = wpi_mem_read(sc, WPI_MEM_POWER);
        wpi_mem_write(sc, WPI_MEM_POWER, tmp & ~0x03000000);
        wpi_mem_unlock(sc);

        for (ntries = 0; ntries < 5000; ntries++) {
                if (WPI_READ(sc, WPI_GPIO_STATUS) & WPI_POWERED)
                        break;
                DELAY(10);
        }
        if (ntries == 5000) {
                aprint_error_dev(sc->sc_dev,
                    "timeout waiting for NIC to power up\n");
                return ETIMEDOUT;
        }
        return 0;
}

static int
wpi_reset(struct wpi_softc *sc)
{
        uint32_t tmp;
        int ntries;

        /* clear any pending interrupts */
        WPI_WRITE(sc, WPI_INTR, 0xffffffff);

        tmp = WPI_READ(sc, WPI_PLL_CTL);
        WPI_WRITE(sc, WPI_PLL_CTL, tmp | WPI_PLL_INIT);

        tmp = WPI_READ(sc, WPI_CHICKEN);
        WPI_WRITE(sc, WPI_CHICKEN, tmp | WPI_CHICKEN_RXNOLOS);

        tmp = WPI_READ(sc, WPI_GPIO_CTL);
        WPI_WRITE(sc, WPI_GPIO_CTL, tmp | WPI_GPIO_INIT);

        /* wait for clock stabilization */
        for (ntries = 0; ntries < 1000; ntries++) {
                if (WPI_READ(sc, WPI_GPIO_CTL) & WPI_GPIO_CLOCK)
                        break;
                DELAY(10);
        }
        if (ntries == 1000) {
                aprint_error_dev(sc->sc_dev,
                    "timeout waiting for clock stabilization\n");
                return ETIMEDOUT;
        }

        /* initialize EEPROM */
        tmp = WPI_READ(sc, WPI_EEPROM_STATUS);
        if ((tmp & WPI_EEPROM_VERSION) == 0) {
                aprint_error_dev(sc->sc_dev, "EEPROM not found\n");
                return EIO;
        }
        WPI_WRITE(sc, WPI_EEPROM_STATUS, tmp & ~WPI_EEPROM_LOCKED);

        return 0;
}

static void
wpi_hw_config(struct wpi_softc *sc)
{
        uint32_t rev, hw;

        /* voodoo from the reference driver */
        hw = WPI_READ(sc, WPI_HWCONFIG);

        rev = pci_conf_read(sc->sc_pct, sc->sc_pcitag, PCI_CLASS_REG);
        rev = PCI_REVISION(rev);
        if ((rev & 0xc0) == 0x40)
                hw |= WPI_HW_ALM_MB;
        else if (!(rev & 0x80))
                hw |= WPI_HW_ALM_MM;

        if (sc->cap == 0x80)
                hw |= WPI_HW_SKU_MRC;

        hw &= ~WPI_HW_REV_D;
        if ((le16toh(sc->rev) & 0xf0) == 0xd0)
                hw |= WPI_HW_REV_D;

        if (sc->type > 1)
                hw |= WPI_HW_TYPE_B;

        DPRINTF(("setting h/w config %x\n", hw));
        WPI_WRITE(sc, WPI_HWCONFIG, hw);
}

static int
wpi_init(struct ifnet *ifp)
{
        struct wpi_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        uint32_t tmp;
        int qid, ntries, error;

        wpi_stop(ifp, 1);
        (void)wpi_reset(sc);

        wpi_mem_lock(sc);
        wpi_mem_write(sc, WPI_MEM_CLOCK1, 0xa00);
        DELAY(20);
        tmp = wpi_mem_read(sc, WPI_MEM_PCIDEV);
        wpi_mem_write(sc, WPI_MEM_PCIDEV, tmp | 0x800);
        wpi_mem_unlock(sc);

        (void)wpi_power_up(sc);
        wpi_hw_config(sc);

        /* init Rx ring */
        wpi_mem_lock(sc);
        WPI_WRITE(sc, WPI_RX_BASE, sc->rxq.desc_dma.paddr);
        WPI_WRITE(sc, WPI_RX_RIDX_PTR, sc->shared_dma.paddr +
            offsetof(struct wpi_shared, next));
        WPI_WRITE(sc, WPI_RX_WIDX, (WPI_RX_RING_COUNT - 1) & ~7);
        WPI_WRITE(sc, WPI_RX_CONFIG, 0xa9601010);
        wpi_mem_unlock(sc);

        /* init Tx rings */
        wpi_mem_lock(sc);
        wpi_mem_write(sc, WPI_MEM_MODE, 2);     /* bypass mode */
        wpi_mem_write(sc, WPI_MEM_RA, 1);       /* enable RA0 */
        wpi_mem_write(sc, WPI_MEM_TXCFG, 0x3f); /* enable all 6 Tx rings */
        wpi_mem_write(sc, WPI_MEM_BYPASS1, 0x10000);
        wpi_mem_write(sc, WPI_MEM_BYPASS2, 0x30002);
        wpi_mem_write(sc, WPI_MEM_MAGIC4, 4);
        wpi_mem_write(sc, WPI_MEM_MAGIC5, 5);

        WPI_WRITE(sc, WPI_TX_BASE_PTR, sc->shared_dma.paddr);
        WPI_WRITE(sc, WPI_MSG_CONFIG, 0xffff05a5);

        for (qid = 0; qid < 6; qid++) {
                WPI_WRITE(sc, WPI_TX_CTL(qid), 0);
                WPI_WRITE(sc, WPI_TX_BASE(qid), 0);
                WPI_WRITE(sc, WPI_TX_CONFIG(qid), 0x80200008);
        }
        wpi_mem_unlock(sc);

        /* clear "radio off" and "disable command" bits (reversed logic) */
        WPI_WRITE(sc, WPI_UCODE_CLR, WPI_RADIO_OFF);
        WPI_WRITE(sc, WPI_UCODE_CLR, WPI_DISABLE_CMD);

        /* clear any pending interrupts */
        WPI_WRITE(sc, WPI_INTR, 0xffffffff);
        /* enable interrupts */
        WPI_WRITE(sc, WPI_MASK, WPI_INTR_MASK);

        /* not sure why/if this is necessary... */
        WPI_WRITE(sc, WPI_UCODE_CLR, WPI_RADIO_OFF);
        WPI_WRITE(sc, WPI_UCODE_CLR, WPI_RADIO_OFF);

        if ((error = wpi_load_firmware(sc)) != 0)
                /* wpi_load_firmware prints error messages for us.  */
                goto fail1;

        /* Check the status of the radio switch */
        mutex_enter(&sc->sc_rsw_mtx);
        if (wpi_getrfkill(sc)) {
                mutex_exit(&sc->sc_rsw_mtx);
                aprint_error_dev(sc->sc_dev,
                    "radio is disabled by hardware switch\n");
                ifp->if_flags &= ~IFF_UP;
                error = EBUSY;
                goto fail1;
        }
        sc->sc_rsw_suspend = false;
        cv_broadcast(&sc->sc_rsw_cv);
        while (sc->sc_rsw_suspend)
                cv_wait(&sc->sc_rsw_cv, &sc->sc_rsw_mtx);
        mutex_exit(&sc->sc_rsw_mtx);

        /* wait for thermal sensors to calibrate */
        for (ntries = 0; ntries < 1000; ntries++) {
                if ((sc->temp = (int)WPI_READ(sc, WPI_TEMPERATURE)) != 0)
                        break;
                DELAY(10);
        }
        if (ntries == 1000) {
                aprint_error_dev(sc->sc_dev,
                    "timeout waiting for thermal sensors calibration\n");
                error = ETIMEDOUT;
                goto fail1;
        }
        DPRINTF(("temperature %d\n", sc->temp));

        if ((error = wpi_config(sc)) != 0) {
                aprint_error_dev(sc->sc_dev, "could not configure device\n");
                goto fail1;
        }

        ifp->if_flags &= ~IFF_OACTIVE;
        ifp->if_flags |= IFF_RUNNING;

        if (ic->ic_opmode != IEEE80211_M_MONITOR) {
                if (ic->ic_roaming != IEEE80211_ROAMING_MANUAL)
                        ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
        }
        else
                ieee80211_new_state(ic, IEEE80211_S_RUN, -1);

        return 0;

fail1:  wpi_stop(ifp, 1);
        return error;
}

static void
wpi_stop1(struct ifnet *ifp, int disable, bool fromintr)
{
        struct wpi_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        uint32_t tmp;
        int ac;

        ifp->if_timer = sc->sc_tx_timer = 0;
        ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);

        ieee80211_new_state(ic, IEEE80211_S_INIT, -1);

        if (fromintr) {
                sc->sc_rsw_suspend = true; // XXX: without mutex or wait
        } else {
                wpi_rsw_suspend(sc);
        }

        /* disable interrupts */
        WPI_WRITE(sc, WPI_MASK, 0);
        WPI_WRITE(sc, WPI_INTR, WPI_INTR_MASK);
        WPI_WRITE(sc, WPI_INTR_STATUS, 0xff);
        WPI_WRITE(sc, WPI_INTR_STATUS, 0x00070000);

        wpi_mem_lock(sc);
        wpi_mem_write(sc, WPI_MEM_MODE, 0);
        wpi_mem_unlock(sc);

        /* reset all Tx rings */
        for (ac = 0; ac < 4; ac++)
                wpi_reset_tx_ring(sc, &sc->txq[ac]);
        wpi_reset_tx_ring(sc, &sc->cmdq);

        /* reset Rx ring */
        wpi_reset_rx_ring(sc, &sc->rxq);

        wpi_mem_lock(sc);
        wpi_mem_write(sc, WPI_MEM_CLOCK2, 0x200);
        wpi_mem_unlock(sc);

        DELAY(5);

        wpi_stop_master(sc);

        tmp = WPI_READ(sc, WPI_RESET);
        WPI_WRITE(sc, WPI_RESET, tmp | WPI_SW_RESET);
}

static void
wpi_stop(struct ifnet *ifp, int disable)
{
        wpi_stop1(ifp, disable, false);
}

static void
wpi_stop_intr(struct ifnet *ifp, int disable)
{
        wpi_stop1(ifp, disable, true);
}

static bool
wpi_resume(device_t dv, const pmf_qual_t *qual)
{
        struct wpi_softc *sc = device_private(dv);

        (void)wpi_reset(sc);

        return true;
}

/*
 * Return whether or not the radio is enabled in hardware
 * (i.e. the rfkill switch is "off").
 */
static int
wpi_getrfkill(struct wpi_softc *sc)
{
        uint32_t tmp;

        wpi_mem_lock(sc);
        tmp = wpi_mem_read(sc, WPI_MEM_RFKILL);
        wpi_mem_unlock(sc);

        KASSERT(mutex_owned(&sc->sc_rsw_mtx));
        if (tmp & 0x01) {
                /* switch is on */
                if (sc->sc_rsw_status != WPI_RSW_ON) {
                        sc->sc_rsw_status = WPI_RSW_ON;
                        sysmon_pswitch_event(&sc->sc_rsw,
                            PSWITCH_EVENT_PRESSED);
                }
        } else {
                /* switch is off */
                if (sc->sc_rsw_status != WPI_RSW_OFF) {
                        sc->sc_rsw_status = WPI_RSW_OFF;
                        sysmon_pswitch_event(&sc->sc_rsw,
                            PSWITCH_EVENT_RELEASED);
                }
        }

        return !(tmp & 0x01);
}

static int
wpi_sysctl_radio(SYSCTLFN_ARGS)
{
        struct sysctlnode node;
        struct wpi_softc *sc;
        int val, error;

        node = *rnode;
        sc = (struct wpi_softc *)node.sysctl_data;

        mutex_enter(&sc->sc_rsw_mtx);
        val = !wpi_getrfkill(sc);
        mutex_exit(&sc->sc_rsw_mtx);

        node.sysctl_data = &val;
        error = sysctl_lookup(SYSCTLFN_CALL(&node));

        if (error || newp == NULL)
                return error;

        return 0;
}

static void
wpi_sysctlattach(struct wpi_softc *sc)
{
        int rc;
        const struct sysctlnode *rnode;
        const struct sysctlnode *cnode;

        struct sysctllog **clog = &sc->sc_sysctllog;

        if ((rc = sysctl_createv(clog, 0, NULL, &rnode,
            CTLFLAG_PERMANENT, CTLTYPE_NODE, device_xname(sc->sc_dev),
            SYSCTL_DESCR("wpi controls and statistics"),
            NULL, 0, NULL, 0, CTL_HW, CTL_CREATE, CTL_EOL)) != 0)
                goto err;

        if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
            CTLFLAG_PERMANENT, CTLTYPE_INT, "radio",
            SYSCTL_DESCR("radio transmitter switch state (0=off, 1=on)"),
            wpi_sysctl_radio, 0, (void *)sc, 0, CTL_CREATE, CTL_EOL)) != 0)
                goto err;

#ifdef WPI_DEBUG
        /* control debugging printfs */
        if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
            CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT,
            "debug", SYSCTL_DESCR("Enable debugging output"),
            NULL, 0, &wpi_debug, 0, CTL_CREATE, CTL_EOL)) != 0)
                goto err;
#endif

        return;
err:
        aprint_error("%s: sysctl_createv failed (rc = %d)\n", __func__, rc);
}

static void
wpi_rsw_suspend(struct wpi_softc *sc)
{
        /* suspend rfkill test thread */
        mutex_enter(&sc->sc_rsw_mtx);
        sc->sc_rsw_suspend = true;
        cv_broadcast(&sc->sc_rsw_cv);
        while (!sc->sc_rsw_suspended)
                cv_wait(&sc->sc_rsw_cv, &sc->sc_rsw_mtx);
        mutex_exit(&sc->sc_rsw_mtx);
}

static void
wpi_rsw_thread(void *arg)
{
        struct wpi_softc *sc = (struct wpi_softc *)arg;

        mutex_enter(&sc->sc_rsw_mtx);
        for (;;) {
                cv_timedwait(&sc->sc_rsw_cv, &sc->sc_rsw_mtx, hz);
                if (sc->sc_dying) {
                        sc->sc_rsw_lwp = NULL;
                        cv_broadcast(&sc->sc_rsw_cv);
                        mutex_exit(&sc->sc_rsw_mtx);
                        kthread_exit(0);
                }
                if (sc->sc_rsw_suspend) {
                        sc->sc_rsw_suspended = true;
                        cv_broadcast(&sc->sc_rsw_cv);
                        while (sc->sc_rsw_suspend || sc->sc_dying)
                                cv_wait(&sc->sc_rsw_cv, &sc->sc_rsw_mtx);
                        sc->sc_rsw_suspended = false;
                        cv_broadcast(&sc->sc_rsw_cv);
                }
                wpi_getrfkill(sc);
        }
}