root/sys/dev/wpi/if_wpi.c
/*-
 * Copyright (c) 2006,2007
 *      Damien Bergamini <damien.bergamini@free.fr>
 *      Benjamin Close <Benjamin.Close@clearchain.com>
 * Copyright (c) 2015 Andriy Voskoboinyk <avos@FreeBSD.org>
 *
 * 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>
/*
 * Driver for Intel PRO/Wireless 3945ABG 802.11 network adapters.
 *
 * The 3945ABG network adapter doesn't use traditional hardware as
 * many other adaptors do. Instead at run time the eeprom is set into a known
 * state and told to load boot firmware. The boot firmware loads an init and a
 * main  binary firmware image into SRAM on the card via DMA.
 * Once the firmware is loaded, the driver/hw then
 * communicate by way of circular dma rings via the SRAM to the firmware.
 *
 * There is 6 memory rings. 1 command ring, 1 rx data ring & 4 tx data rings.
 * The 4 tx data rings allow for prioritization QoS.
 *
 * The rx data ring consists of 32 dma buffers. Two registers are used to
 * indicate where in the ring the driver and the firmware are up to. The
 * driver sets the initial read index (reg1) and the initial write index (reg2),
 * the firmware updates the read index (reg1) on rx of a packet and fires an
 * interrupt. The driver then processes the buffers starting at reg1 indicating
 * to the firmware which buffers have been accessed by updating reg2. At the
 * same time allocating new memory for the processed buffer.
 *
 * A similar thing happens with the tx rings. The difference is the firmware
 * stop processing buffers once the queue is full and until confirmation
 * of a successful transmition (tx_done) has occurred.
 *
 * The command ring operates in the same manner as the tx queues.
 *
 * All communication direct to the card (ie eeprom) is classed as Stage1
 * communication
 *
 * All communication via the firmware to the card is classed as State2.
 * The firmware consists of 2 parts. A bootstrap firmware and a runtime
 * firmware. The bootstrap firmware and runtime firmware are loaded
 * from host memory via dma to the card then told to execute. From this point
 * on the majority of communications between the driver and the card goes
 * via the firmware.
 */

#include "opt_wlan.h"
#include "opt_wpi.h"

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

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

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

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

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

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_radiotap.h>
#include <net80211/ieee80211_regdomain.h>
#include <net80211/ieee80211_ratectl.h>

#include <dev/wpi/if_wpireg.h>
#include <dev/wpi/if_wpivar.h>
#include <dev/wpi/if_wpi_debug.h>

struct wpi_ident {
        uint16_t        vendor;
        uint16_t        device;
        uint16_t        subdevice;
        const char      *name;
};

static const struct wpi_ident wpi_ident_table[] = {
        /* The below entries support ABG regardless of the subid */
        { 0x8086, 0x4222,    0x0, "Intel(R) PRO/Wireless 3945ABG" },
        { 0x8086, 0x4227,    0x0, "Intel(R) PRO/Wireless 3945ABG" },
        /* The below entries only support BG */
        { 0x8086, 0x4222, 0x1005, "Intel(R) PRO/Wireless 3945BG"  },
        { 0x8086, 0x4222, 0x1034, "Intel(R) PRO/Wireless 3945BG"  },
        { 0x8086, 0x4227, 0x1014, "Intel(R) PRO/Wireless 3945BG"  },
        { 0x8086, 0x4222, 0x1044, "Intel(R) PRO/Wireless 3945BG"  },
        { 0, 0, 0, NULL }
};

static int      wpi_probe(device_t);
static int      wpi_attach(device_t);
static void     wpi_radiotap_attach(struct wpi_softc *);
static void     wpi_sysctlattach(struct wpi_softc *);
static void     wpi_init_beacon(struct wpi_vap *);
static struct ieee80211vap *wpi_vap_create(struct ieee80211com *,
                    const char [IFNAMSIZ], int, enum ieee80211_opmode, int,
                    const uint8_t [IEEE80211_ADDR_LEN],
                    const uint8_t [IEEE80211_ADDR_LEN]);
static void     wpi_vap_delete(struct ieee80211vap *);
static int      wpi_detach(device_t);
static int      wpi_shutdown(device_t);
static int      wpi_suspend(device_t);
static int      wpi_resume(device_t);
static int      wpi_nic_lock(struct wpi_softc *);
static int      wpi_read_prom_data(struct wpi_softc *, uint32_t, void *, int);
static void     wpi_dma_map_addr(void *, bus_dma_segment_t *, int, int);
static int      wpi_dma_contig_alloc(struct wpi_softc *, struct wpi_dma_info *,
                    void **, bus_size_t, bus_size_t);
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 int      wpi_alloc_rx_ring(struct wpi_softc *);
static void     wpi_update_rx_ring(struct wpi_softc *);
static void     wpi_update_rx_ring_ps(struct wpi_softc *);
static void     wpi_reset_rx_ring(struct wpi_softc *);
static void     wpi_free_rx_ring(struct wpi_softc *);
static int      wpi_alloc_tx_ring(struct wpi_softc *, struct wpi_tx_ring *,
                    uint8_t);
static void     wpi_update_tx_ring(struct wpi_softc *, struct wpi_tx_ring *);
static void     wpi_update_tx_ring_ps(struct wpi_softc *,
                    struct wpi_tx_ring *);
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 int      wpi_read_eeprom(struct wpi_softc *,
                    uint8_t macaddr[IEEE80211_ADDR_LEN]);
static uint32_t wpi_eeprom_channel_flags(struct wpi_eeprom_chan *);
static void     wpi_read_eeprom_band(struct wpi_softc *, uint8_t, int, int *,
                    struct ieee80211_channel[]);
static int      wpi_read_eeprom_channels(struct wpi_softc *, uint8_t);
static struct wpi_eeprom_chan *wpi_find_eeprom_channel(struct wpi_softc *,
                    struct ieee80211_channel *);
static void     wpi_getradiocaps(struct ieee80211com *, int, int *,
                    struct ieee80211_channel[]);
static int      wpi_setregdomain(struct ieee80211com *,
                    struct ieee80211_regdomain *, int,
                    struct ieee80211_channel[]);
static int      wpi_read_eeprom_group(struct wpi_softc *, uint8_t);
static struct ieee80211_node *wpi_node_alloc(struct ieee80211vap *,
                    const uint8_t mac[IEEE80211_ADDR_LEN]);
static void     wpi_node_free(struct ieee80211_node *);
static void     wpi_ibss_recv_mgmt(struct ieee80211_node *, struct mbuf *, int,
                    const struct ieee80211_rx_stats *,
                    int, int);
static void     wpi_restore_node(void *, struct ieee80211_node *);
static void     wpi_restore_node_table(struct wpi_softc *, struct wpi_vap *);
static int      wpi_newstate(struct ieee80211vap *, enum ieee80211_state, int);
static void     wpi_calib_timeout(void *);
static void     wpi_rx_done(struct wpi_softc *, struct wpi_rx_desc *,
                    struct wpi_rx_data *);
static void     wpi_rx_statistics(struct wpi_softc *, struct wpi_rx_desc *,
                    struct wpi_rx_data *);
static void     wpi_tx_done(struct wpi_softc *, struct wpi_rx_desc *);
static void     wpi_cmd_done(struct wpi_softc *, struct wpi_rx_desc *);
static void     wpi_notif_intr(struct wpi_softc *);
static void     wpi_wakeup_intr(struct wpi_softc *);
#ifdef WPI_DEBUG
static void     wpi_debug_registers(struct wpi_softc *);
#endif
static void     wpi_fatal_intr(struct wpi_softc *);
static void     wpi_intr(void *);
static void     wpi_free_txfrags(struct wpi_softc *, uint16_t);
static int      wpi_cmd2(struct wpi_softc *, struct wpi_buf *);
static int      wpi_tx_data(struct wpi_softc *, struct mbuf *,
                    struct ieee80211_node *);
static int      wpi_tx_data_raw(struct wpi_softc *, struct mbuf *,
                    struct ieee80211_node *,
                    const struct ieee80211_bpf_params *);
static int      wpi_raw_xmit(struct ieee80211_node *, struct mbuf *,
                    const struct ieee80211_bpf_params *);
static int      wpi_transmit(struct ieee80211com *, struct mbuf *);
static void     wpi_watchdog_rfkill(void *);
static void     wpi_scan_timeout(void *);
static void     wpi_tx_timeout(void *);
static void     wpi_parent(struct ieee80211com *);
static int      wpi_cmd(struct wpi_softc *, uint8_t, const void *, uint16_t,
                    int);
static int      wpi_mrr_setup(struct wpi_softc *);
static int      wpi_add_node(struct wpi_softc *, struct ieee80211_node *);
static int      wpi_add_broadcast_node(struct wpi_softc *, int);
static int      wpi_add_ibss_node(struct wpi_softc *, struct ieee80211_node *);
static void     wpi_del_node(struct wpi_softc *, struct ieee80211_node *);
static int      wpi_updateedca(struct ieee80211com *);
static void     wpi_set_promisc(struct wpi_softc *);
static void     wpi_update_promisc(struct ieee80211com *);
static void     wpi_update_mcast(struct ieee80211com *);
static void     wpi_set_led(struct wpi_softc *, uint8_t, uint8_t, uint8_t);
static int      wpi_set_timing(struct wpi_softc *, struct ieee80211_node *);
static void     wpi_power_calibration(struct wpi_softc *);
static int      wpi_set_txpower(struct wpi_softc *, int);
static int      wpi_get_power_index(struct wpi_softc *,
                    struct wpi_power_group *, uint8_t, int, int);
static int      wpi_set_pslevel(struct wpi_softc *, uint8_t, int, int);
static int      wpi_send_btcoex(struct wpi_softc *);
static int      wpi_send_rxon(struct wpi_softc *, int, int);
static int      wpi_config(struct wpi_softc *);
static uint16_t wpi_get_active_dwell_time(struct wpi_softc *,
                    struct ieee80211_channel *, uint8_t);
static uint16_t wpi_limit_dwell(struct wpi_softc *, uint16_t);
static uint16_t wpi_get_passive_dwell_time(struct wpi_softc *,
                    struct ieee80211_channel *);
static uint32_t wpi_get_scan_pause_time(uint32_t, uint16_t);
static int      wpi_scan(struct wpi_softc *, struct ieee80211_channel *);
static int      wpi_auth(struct wpi_softc *, struct ieee80211vap *);
static int      wpi_config_beacon(struct wpi_vap *);
static int      wpi_setup_beacon(struct wpi_softc *, struct ieee80211_node *);
static void     wpi_update_beacon(struct ieee80211vap *, int);
static void     wpi_newassoc(struct ieee80211_node *, int);
static int      wpi_run(struct wpi_softc *, struct ieee80211vap *);
static int      wpi_load_key(struct ieee80211_node *,
                    const struct ieee80211_key *);
static void     wpi_load_key_cb(void *, struct ieee80211_node *);
static int      wpi_set_global_keys(struct ieee80211_node *);
static int      wpi_del_key(struct ieee80211_node *,
                    const struct ieee80211_key *);
static void     wpi_del_key_cb(void *, struct ieee80211_node *);
static int      wpi_process_key(struct ieee80211vap *,
                    const struct ieee80211_key *, int);
static int      wpi_key_set(struct ieee80211vap *,
                    const struct ieee80211_key *);
static int      wpi_key_delete(struct ieee80211vap *,
                    const struct ieee80211_key *);
static int      wpi_post_alive(struct wpi_softc *);
static int      wpi_load_bootcode(struct wpi_softc *, const uint8_t *,
                    uint32_t);
static int      wpi_load_firmware(struct wpi_softc *);
static int      wpi_read_firmware(struct wpi_softc *);
static void     wpi_unload_firmware(struct wpi_softc *);
static int      wpi_clock_wait(struct wpi_softc *);
static int      wpi_apm_init(struct wpi_softc *);
static void     wpi_apm_stop_master(struct wpi_softc *);
static void     wpi_apm_stop(struct wpi_softc *);
static void     wpi_nic_config(struct wpi_softc *);
static int      wpi_hw_init(struct wpi_softc *);
static void     wpi_hw_stop(struct wpi_softc *);
static void     wpi_radio_on(void *, int);
static void     wpi_radio_off(void *, int);
static int      wpi_init(struct wpi_softc *);
static void     wpi_stop_locked(struct wpi_softc *);
static void     wpi_stop(struct wpi_softc *);
static void     wpi_scan_start(struct ieee80211com *);
static void     wpi_scan_end(struct ieee80211com *);
static void     wpi_set_channel(struct ieee80211com *);
static void     wpi_scan_curchan(struct ieee80211_scan_state *, unsigned long);
static void     wpi_scan_mindwell(struct ieee80211_scan_state *);

static device_method_t wpi_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         wpi_probe),
        DEVMETHOD(device_attach,        wpi_attach),
        DEVMETHOD(device_detach,        wpi_detach),
        DEVMETHOD(device_shutdown,      wpi_shutdown),
        DEVMETHOD(device_suspend,       wpi_suspend),
        DEVMETHOD(device_resume,        wpi_resume),

        DEVMETHOD_END
};

static driver_t wpi_driver = {
        "wpi",
        wpi_methods,
        sizeof (struct wpi_softc)
};

DRIVER_MODULE(wpi, pci, wpi_driver, NULL, NULL);

MODULE_VERSION(wpi, 1);

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

static int
wpi_probe(device_t dev)
{
        const struct wpi_ident *ident;

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

static int
wpi_attach(device_t dev)
{
        struct wpi_softc *sc = (struct wpi_softc *)device_get_softc(dev);
        struct ieee80211com *ic;
        uint8_t i;
        int error, rid;
#ifdef WPI_DEBUG
        int supportsa = 1;
        const struct wpi_ident *ident;
#endif

        sc->sc_dev = dev;

#ifdef WPI_DEBUG
        error = resource_int_value(device_get_name(sc->sc_dev),
            device_get_unit(sc->sc_dev), "debug", &(sc->sc_debug));
        if (error != 0)
                sc->sc_debug = 0;
#else
        sc->sc_debug = 0;
#endif

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /*
         * Get the offset of the PCI Express Capability Structure in PCI
         * Configuration Space.
         */
        error = pci_find_cap(dev, PCIY_EXPRESS, &sc->sc_cap_off);
        if (error != 0) {
                device_printf(dev, "PCIe capability structure not found!\n");
                return error;
        }

        /*
         * Some card's only support 802.11b/g not a, check to see if
         * this is one such card. A 0x0 in the subdevice table indicates
         * the entire subdevice range is to be ignored.
         */
#ifdef WPI_DEBUG
        for (ident = wpi_ident_table; ident->name != NULL; ident++) {
                if (ident->subdevice &&
                    pci_get_subdevice(dev) == ident->subdevice) {
                    supportsa = 0;
                    break;
                }
        }
#endif

        /* Clear device-specific "PCI retry timeout" register (41h). */
        pci_write_config(dev, 0x41, 0, 1);

        /* Enable bus-mastering. */
        pci_enable_busmaster(dev);

        rid = PCIR_BAR(0);
        sc->mem = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
            RF_ACTIVE);
        if (sc->mem == NULL) {
                device_printf(dev, "can't map mem space\n");
                return ENOMEM;
        }
        sc->sc_st = rman_get_bustag(sc->mem);
        sc->sc_sh = rman_get_bushandle(sc->mem);

        rid = 1;
        if (pci_alloc_msi(dev, &rid) == 0)
                rid = 1;
        else
                rid = 0;
        /* Install interrupt handler. */
        sc->irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid, RF_ACTIVE |
            (rid != 0 ? 0 : RF_SHAREABLE));
        if (sc->irq == NULL) {
                device_printf(dev, "can't map interrupt\n");
                error = ENOMEM;
                goto fail;
        }

        WPI_LOCK_INIT(sc);
        WPI_TX_LOCK_INIT(sc);
        WPI_RXON_LOCK_INIT(sc);
        WPI_NT_LOCK_INIT(sc);
        WPI_TXQ_LOCK_INIT(sc);
        WPI_TXQ_STATE_LOCK_INIT(sc);

        /* Allocate DMA memory for firmware transfers. */
        if ((error = wpi_alloc_fwmem(sc)) != 0) {
                device_printf(dev,
                    "could not allocate memory for firmware, error %d\n",
                    error);
                goto fail;
        }

        /* Allocate shared page. */
        if ((error = wpi_alloc_shared(sc)) != 0) {
                device_printf(dev, "could not allocate shared page\n");
                goto fail;
        }

        /* Allocate TX rings - 4 for QoS purposes, 1 for commands. */
        for (i = 0; i < WPI_DRV_NTXQUEUES; i++) {
                if ((error = wpi_alloc_tx_ring(sc, &sc->txq[i], i)) != 0) {
                        device_printf(dev,
                            "could not allocate TX ring %d, error %d\n", i,
                            error);
                        goto fail;
                }
        }

        /* Allocate RX ring. */
        if ((error = wpi_alloc_rx_ring(sc)) != 0) {
                device_printf(dev, "could not allocate RX ring, error %d\n",
                    error);
                goto fail;
        }

        /* Clear pending interrupts. */
        WPI_WRITE(sc, WPI_INT, 0xffffffff);

        ic = &sc->sc_ic;
        ic->ic_softc = sc;
        ic->ic_name = device_get_nameunit(dev);
        ic->ic_phytype = IEEE80211_T_OFDM;      /* not only, but not used */
        ic->ic_opmode = IEEE80211_M_STA;        /* default to BSS mode */

        /* Set device capabilities. */
        ic->ic_caps =
                  IEEE80211_C_STA               /* station mode supported */
                | IEEE80211_C_IBSS              /* IBSS mode supported */
                | IEEE80211_C_HOSTAP            /* Host access point mode */
                | IEEE80211_C_MONITOR           /* monitor mode supported */
                | IEEE80211_C_AHDEMO            /* adhoc demo mode */
                | IEEE80211_C_BGSCAN            /* capable of bg scanning */
                | IEEE80211_C_TXFRAG            /* handle tx frags */
                | IEEE80211_C_TXPMGT            /* tx power management */
                | IEEE80211_C_SHSLOT            /* short slot time supported */
                | IEEE80211_C_WPA               /* 802.11i */
                | IEEE80211_C_SHPREAMBLE        /* short preamble supported */
                | IEEE80211_C_WME               /* 802.11e */
                | IEEE80211_C_PMGT              /* Station-side power mgmt */
                ;

        ic->ic_cryptocaps =
                  IEEE80211_CRYPTO_AES_CCM;

        /*
         * Read in the eeprom and also setup the channels for
         * net80211. We don't set the rates as net80211 does this for us
         */
        if ((error = wpi_read_eeprom(sc, ic->ic_macaddr)) != 0) {
                device_printf(dev, "could not read EEPROM, error %d\n",
                    error);
                goto fail;
        }

#ifdef WPI_DEBUG
        if (bootverbose) {
                device_printf(sc->sc_dev, "Regulatory Domain: %.4s\n",
                    sc->domain);
                device_printf(sc->sc_dev, "Hardware Type: %c\n",
                    sc->type > 1 ? 'B': '?');
                device_printf(sc->sc_dev, "Hardware Revision: %c\n",
                    ((sc->rev & 0xf0) == 0xd0) ? 'D': '?');
                device_printf(sc->sc_dev, "SKU %s support 802.11a\n",
                    supportsa ? "does" : "does not");

                /* XXX hw_config uses the PCIDEV for the Hardware rev. Must
                   check what sc->rev really represents - benjsc 20070615 */
        }
#endif

        ieee80211_ifattach(ic);
        ic->ic_vap_create = wpi_vap_create;
        ic->ic_vap_delete = wpi_vap_delete;
        ic->ic_parent = wpi_parent;
        ic->ic_raw_xmit = wpi_raw_xmit;
        ic->ic_transmit = wpi_transmit;
        ic->ic_node_alloc = wpi_node_alloc;
        sc->sc_node_free = ic->ic_node_free;
        ic->ic_node_free = wpi_node_free;
        ic->ic_wme.wme_update = wpi_updateedca;
        ic->ic_update_promisc = wpi_update_promisc;
        ic->ic_update_mcast = wpi_update_mcast;
        ic->ic_newassoc = wpi_newassoc;
        ic->ic_scan_start = wpi_scan_start;
        ic->ic_scan_end = wpi_scan_end;
        ic->ic_set_channel = wpi_set_channel;
        ic->ic_scan_curchan = wpi_scan_curchan;
        ic->ic_scan_mindwell = wpi_scan_mindwell;
        ic->ic_getradiocaps = wpi_getradiocaps;
        ic->ic_setregdomain = wpi_setregdomain;

        sc->sc_update_rx_ring = wpi_update_rx_ring;
        sc->sc_update_tx_ring = wpi_update_tx_ring;

        wpi_radiotap_attach(sc);

        /* Setup Tx status flags (constant). */
        sc->sc_txs.flags = IEEE80211_RATECTL_STATUS_PKTLEN |
            IEEE80211_RATECTL_STATUS_SHORT_RETRY |
            IEEE80211_RATECTL_STATUS_LONG_RETRY;

        callout_init_mtx(&sc->calib_to, &sc->rxon_mtx, 0);
        callout_init_mtx(&sc->scan_timeout, &sc->rxon_mtx, 0);
        callout_init_mtx(&sc->tx_timeout, &sc->txq_state_mtx, 0);
        callout_init_mtx(&sc->watchdog_rfkill, &sc->sc_mtx, 0);
        TASK_INIT(&sc->sc_radiooff_task, 0, wpi_radio_off, sc);
        TASK_INIT(&sc->sc_radioon_task, 0, wpi_radio_on, sc);

        wpi_sysctlattach(sc);

        /*
         * Hook our interrupt after all initialization is complete.
         */
        error = bus_setup_intr(dev, sc->irq, INTR_TYPE_NET | INTR_MPSAFE,
            NULL, wpi_intr, sc, &sc->sc_ih);
        if (error != 0) {
                device_printf(dev, "can't establish interrupt, error %d\n",
                    error);
                goto fail;
        }

        if (bootverbose)
                ieee80211_announce(ic);

#ifdef WPI_DEBUG
        if (sc->sc_debug & WPI_DEBUG_HW)
                ieee80211_announce_channels(ic);
#endif

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);
        return 0;

fail:   wpi_detach(dev);
        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);
        return error;
}

/*
 * Attach the interface to 802.11 radiotap.
 */
static void
wpi_radiotap_attach(struct wpi_softc *sc)
{
        struct wpi_rx_radiotap_header *rxtap = &sc->sc_rxtap;
        struct wpi_tx_radiotap_header *txtap = &sc->sc_txtap;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);
        ieee80211_radiotap_attach(&sc->sc_ic,
            &txtap->wt_ihdr, sizeof(*txtap), WPI_TX_RADIOTAP_PRESENT,
            &rxtap->wr_ihdr, sizeof(*rxtap), WPI_RX_RADIOTAP_PRESENT);
        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);
}

static void
wpi_sysctlattach(struct wpi_softc *sc)
{
#ifdef WPI_DEBUG
        struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
        struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);

        SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
            "debug", CTLFLAG_RW, &sc->sc_debug, sc->sc_debug,
                "control debugging printfs");
#endif
}

static void
wpi_init_beacon(struct wpi_vap *wvp)
{
        struct wpi_buf *bcn = &wvp->wv_bcbuf;
        struct wpi_cmd_beacon *cmd = (struct wpi_cmd_beacon *)&bcn->data;

        cmd->id = WPI_ID_BROADCAST;
        cmd->ofdm_mask = 0xff;
        cmd->cck_mask = 0x0f;
        cmd->lifetime = htole32(WPI_LIFETIME_INFINITE);

        /*
         * XXX WPI_TX_AUTO_SEQ seems to be ignored - workaround this issue
         * XXX by using WPI_TX_NEED_ACK instead (with some side effects).
         */
        cmd->flags = htole32(WPI_TX_NEED_ACK | WPI_TX_INSERT_TSTAMP);

        bcn->code = WPI_CMD_SET_BEACON;
        bcn->ac = WPI_CMD_QUEUE_NUM;
        bcn->size = sizeof(struct wpi_cmd_beacon);
}

static struct ieee80211vap *
wpi_vap_create(struct ieee80211com *ic, const char name[IFNAMSIZ], int unit,
    enum ieee80211_opmode opmode, int flags,
    const uint8_t bssid[IEEE80211_ADDR_LEN],
    const uint8_t mac[IEEE80211_ADDR_LEN])
{
        struct wpi_vap *wvp;
        struct ieee80211vap *vap;

        if (!TAILQ_EMPTY(&ic->ic_vaps))         /* only one at a time */
                return NULL;

        wvp = malloc(sizeof(struct wpi_vap), M_80211_VAP, M_WAITOK | M_ZERO);
        vap = &wvp->wv_vap;
        ieee80211_vap_setup(ic, vap, name, unit, opmode, flags, bssid);

        if (opmode == IEEE80211_M_IBSS || opmode == IEEE80211_M_HOSTAP) {
                WPI_VAP_LOCK_INIT(wvp);
                wpi_init_beacon(wvp);
        }

        /* Override with driver methods. */
        vap->iv_key_set = wpi_key_set;
        vap->iv_key_delete = wpi_key_delete;
        if (opmode == IEEE80211_M_IBSS) {
                wvp->wv_recv_mgmt = vap->iv_recv_mgmt;
                vap->iv_recv_mgmt = wpi_ibss_recv_mgmt;
        }
        wvp->wv_newstate = vap->iv_newstate;
        vap->iv_newstate = wpi_newstate;
        vap->iv_update_beacon = wpi_update_beacon;
        vap->iv_max_aid = WPI_ID_IBSS_MAX - WPI_ID_IBSS_MIN + 1;

        ieee80211_ratectl_init(vap);
        /* Complete setup. */
        ieee80211_vap_attach(vap, ieee80211_media_change,
            ieee80211_media_status, mac);
        ic->ic_opmode = opmode;
        return vap;
}

static void
wpi_vap_delete(struct ieee80211vap *vap)
{
        struct wpi_vap *wvp = WPI_VAP(vap);
        struct wpi_buf *bcn = &wvp->wv_bcbuf;
        enum ieee80211_opmode opmode = vap->iv_opmode;

        ieee80211_ratectl_deinit(vap);
        ieee80211_vap_detach(vap);

        if (opmode == IEEE80211_M_IBSS || opmode == IEEE80211_M_HOSTAP) {
                if (bcn->m != NULL)
                        m_freem(bcn->m);

                WPI_VAP_LOCK_DESTROY(wvp);
        }

        free(wvp, M_80211_VAP);
}

static int
wpi_detach(device_t dev)
{
        struct wpi_softc *sc = device_get_softc(dev);
        struct ieee80211com *ic = &sc->sc_ic;
        uint8_t qid;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        if (ic->ic_vap_create == wpi_vap_create) {
                ieee80211_draintask(ic, &sc->sc_radioon_task);
                ieee80211_draintask(ic, &sc->sc_radiooff_task);

                wpi_stop(sc);

                callout_drain(&sc->watchdog_rfkill);
                callout_drain(&sc->tx_timeout);
                callout_drain(&sc->scan_timeout);
                callout_drain(&sc->calib_to);
                ieee80211_ifdetach(ic);
        }

        /* Uninstall interrupt handler. */
        if (sc->irq != NULL) {
                bus_teardown_intr(dev, sc->irq, sc->sc_ih);
                bus_release_resource(dev, SYS_RES_IRQ, rman_get_rid(sc->irq),
                    sc->irq);
                pci_release_msi(dev);
        }

        if (sc->txq[0].data_dmat) {
                /* Free DMA resources. */
                for (qid = 0; qid < WPI_DRV_NTXQUEUES; qid++)
                        wpi_free_tx_ring(sc, &sc->txq[qid]);

                wpi_free_rx_ring(sc);
                wpi_free_shared(sc);
        }

        if (sc->fw_dma.tag)
                wpi_free_fwmem(sc);
                
        if (sc->mem != NULL)
                bus_release_resource(dev, SYS_RES_MEMORY,
                    rman_get_rid(sc->mem), sc->mem);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);
        WPI_TXQ_STATE_LOCK_DESTROY(sc);
        WPI_TXQ_LOCK_DESTROY(sc);
        WPI_NT_LOCK_DESTROY(sc);
        WPI_RXON_LOCK_DESTROY(sc);
        WPI_TX_LOCK_DESTROY(sc);
        WPI_LOCK_DESTROY(sc);
        return 0;
}

static int
wpi_shutdown(device_t dev)
{
        struct wpi_softc *sc = device_get_softc(dev);

        wpi_stop(sc);
        return 0;
}

static int
wpi_suspend(device_t dev)
{
        struct wpi_softc *sc = device_get_softc(dev);
        struct ieee80211com *ic = &sc->sc_ic;

        ieee80211_suspend_all(ic);
        return 0;
}

static int
wpi_resume(device_t dev)
{
        struct wpi_softc *sc = device_get_softc(dev);
        struct ieee80211com *ic = &sc->sc_ic;

        /* Clear device-specific "PCI retry timeout" register (41h). */
        pci_write_config(dev, 0x41, 0, 1);

        ieee80211_resume_all(ic);
        return 0;
}

/*
 * Grab exclusive access to NIC memory.
 */
static int
wpi_nic_lock(struct wpi_softc *sc)
{
        int ntries;

        /* Request exclusive access to NIC. */
        WPI_SETBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);

        /* Spin until we actually get the lock. */
        for (ntries = 0; ntries < 1000; ntries++) {
                if ((WPI_READ(sc, WPI_GP_CNTRL) &
                    (WPI_GP_CNTRL_MAC_ACCESS_ENA | WPI_GP_CNTRL_SLEEP)) ==
                    WPI_GP_CNTRL_MAC_ACCESS_ENA)
                        return 0;
                DELAY(10);
        }

        device_printf(sc->sc_dev, "could not lock memory\n");

        return ETIMEDOUT;
}

/*
 * Release lock on NIC memory.
 */
static __inline void
wpi_nic_unlock(struct wpi_softc *sc)
{
        WPI_CLRBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);
}

static __inline uint32_t
wpi_prph_read(struct wpi_softc *sc, uint32_t addr)
{
        WPI_WRITE(sc, WPI_PRPH_RADDR, WPI_PRPH_DWORD | addr);
        WPI_BARRIER_READ_WRITE(sc);
        return WPI_READ(sc, WPI_PRPH_RDATA);
}

static __inline void
wpi_prph_write(struct wpi_softc *sc, uint32_t addr, uint32_t data)
{
        WPI_WRITE(sc, WPI_PRPH_WADDR, WPI_PRPH_DWORD | addr);
        WPI_BARRIER_WRITE(sc);
        WPI_WRITE(sc, WPI_PRPH_WDATA, data);
}

static __inline void
wpi_prph_setbits(struct wpi_softc *sc, uint32_t addr, uint32_t mask)
{
        wpi_prph_write(sc, addr, wpi_prph_read(sc, addr) | mask);
}

static __inline void
wpi_prph_clrbits(struct wpi_softc *sc, uint32_t addr, uint32_t mask)
{
        wpi_prph_write(sc, addr, wpi_prph_read(sc, addr) & ~mask);
}

static __inline void
wpi_prph_write_region_4(struct wpi_softc *sc, uint32_t addr,
    const uint32_t *data, uint32_t count)
{
        for (; count != 0; count--, data++, addr += 4)
                wpi_prph_write(sc, addr, *data);
}

static __inline uint32_t
wpi_mem_read(struct wpi_softc *sc, uint32_t addr)
{
        WPI_WRITE(sc, WPI_MEM_RADDR, addr);
        WPI_BARRIER_READ_WRITE(sc);
        return WPI_READ(sc, WPI_MEM_RDATA);
}

static __inline void
wpi_mem_read_region_4(struct wpi_softc *sc, uint32_t addr, uint32_t *data,
    int count)
{
        for (; count > 0; count--, addr += 4)
                *data++ = wpi_mem_read(sc, addr);
}

static int
wpi_read_prom_data(struct wpi_softc *sc, uint32_t addr, void *data, int count)
{
        uint8_t *out = data;
        uint32_t val;
        int error, ntries;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        if ((error = wpi_nic_lock(sc)) != 0)
                return error;

        for (; count > 0; count -= 2, addr++) {
                WPI_WRITE(sc, WPI_EEPROM, addr << 2);
                for (ntries = 0; ntries < 10; ntries++) {
                        val = WPI_READ(sc, WPI_EEPROM);
                        if (val & WPI_EEPROM_READ_VALID)
                                break;
                        DELAY(5);
                }
                if (ntries == 10) {
                        device_printf(sc->sc_dev,
                            "timeout reading ROM at 0x%x\n", addr);
                        return ETIMEDOUT;
                }
                *out++= val >> 16;
                if (count > 1)
                        *out ++= val >> 24;
        }

        wpi_nic_unlock(sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;
}

static void
wpi_dma_map_addr(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
{
        if (error != 0)
                return;
        KASSERT(nsegs == 1, ("too many DMA segments, %d should be 1", nsegs));
        *(bus_addr_t *)arg = segs[0].ds_addr;
}

/*
 * Allocates a contiguous block of dma memory of the requested size and
 * alignment.
 */
static int
wpi_dma_contig_alloc(struct wpi_softc *sc, struct wpi_dma_info *dma,
    void **kvap, bus_size_t size, bus_size_t alignment)
{
        int error;

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

        error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), alignment,
            0, BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL, size,
            1, size, 0, NULL, NULL, &dma->tag);
        if (error != 0)
                goto fail;

        error = bus_dmamem_alloc(dma->tag, (void **)&dma->vaddr,
            BUS_DMA_NOWAIT | BUS_DMA_ZERO | BUS_DMA_COHERENT, &dma->map);
        if (error != 0)
                goto fail;

        error = bus_dmamap_load(dma->tag, dma->map, dma->vaddr, size,
            wpi_dma_map_addr, &dma->paddr, BUS_DMA_NOWAIT);
        if (error != 0)
                goto fail;

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

        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->vaddr != NULL) {
                bus_dmamap_sync(dma->tag, dma->map,
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(dma->tag, dma->map);
                bus_dmamem_free(dma->tag, dma->vaddr, dma->map);
                dma->vaddr = NULL;
        }
        if (dma->tag != NULL) {
                bus_dma_tag_destroy(dma->tag);
                dma->tag = NULL;
        }
}

/*
 * Allocate a shared page between host and NIC.
 */
static int
wpi_alloc_shared(struct wpi_softc *sc)
{
        /* Shared buffer must be aligned on a 4KB boundary. */
        return wpi_dma_contig_alloc(sc, &sc->shared_dma,
            (void **)&sc->shared, sizeof (struct wpi_shared), 4096);
}

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)
{
        /* Must be aligned on a 16-byte boundary. */
        return wpi_dma_contig_alloc(sc, &sc->fw_dma, NULL,
            WPI_FW_TEXT_MAXSZ + WPI_FW_DATA_MAXSZ, 16);
}

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

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

        ring->cur = 0;
        ring->update = 0;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /* Allocate RX descriptors (16KB aligned.) */
        size = WPI_RX_RING_COUNT * sizeof (uint32_t);
        error = wpi_dma_contig_alloc(sc, &ring->desc_dma,
            (void **)&ring->desc, size, WPI_RING_DMA_ALIGN);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not allocate RX ring DMA memory, error %d\n",
                    __func__, error);
                goto fail;
        }

        /* Create RX buffer DMA tag. */
        error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), 1, 0, 
            BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL,
            MJUMPAGESIZE, 1, MJUMPAGESIZE, 0, NULL, NULL, &ring->data_dmat);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not create RX buf DMA tag, error %d\n",
                    __func__, error);
                goto fail;
        }

        /*
         * Allocate and map RX buffers.
         */
        for (i = 0; i < WPI_RX_RING_COUNT; i++) {
                struct wpi_rx_data *data = &ring->data[i];
                bus_addr_t paddr;

                error = bus_dmamap_create(ring->data_dmat, 0, &data->map);
                if (error != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not create RX buf DMA map, error %d\n",
                            __func__, error);
                        goto fail;
                }

                data->m = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUMPAGESIZE);
                if (data->m == NULL) {
                        device_printf(sc->sc_dev,
                            "%s: could not allocate RX mbuf\n", __func__);
                        error = ENOBUFS;
                        goto fail;
                }

                error = bus_dmamap_load(ring->data_dmat, data->map,
                    mtod(data->m, void *), MJUMPAGESIZE, wpi_dma_map_addr,
                    &paddr, BUS_DMA_NOWAIT);
                if (error != 0 && error != EFBIG) {
                        device_printf(sc->sc_dev,
                            "%s: can't map mbuf (error %d)\n", __func__,
                            error);
                        goto fail;
                }

                /* Set physical address of RX buffer. */
                ring->desc[i] = htole32(paddr);
        }

        bus_dmamap_sync(ring->desc_dma.tag, ring->desc_dma.map,
            BUS_DMASYNC_PREWRITE);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;

fail:   wpi_free_rx_ring(sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);

        return error;
}

static void
wpi_update_rx_ring(struct wpi_softc *sc)
{
        WPI_WRITE(sc, WPI_FH_RX_WPTR, sc->rxq.cur & ~7);
}

static void
wpi_update_rx_ring_ps(struct wpi_softc *sc)
{
        struct wpi_rx_ring *ring = &sc->rxq;

        if (ring->update != 0) {
                /* Wait for INT_WAKEUP event. */
                return;
        }

        WPI_TXQ_LOCK(sc);
        WPI_SETBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);
        if (WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_SLEEP) {
                DPRINTF(sc, WPI_DEBUG_PWRSAVE, "%s: wakeup request\n",
                    __func__);
                ring->update = 1;
        } else {
                wpi_update_rx_ring(sc);
                WPI_CLRBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);
        }
        WPI_TXQ_UNLOCK(sc);
}

static void
wpi_reset_rx_ring(struct wpi_softc *sc)
{
        struct wpi_rx_ring *ring = &sc->rxq;
        int ntries;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (wpi_nic_lock(sc) == 0) {
                WPI_WRITE(sc, WPI_FH_RX_CONFIG, 0);
                for (ntries = 0; ntries < 1000; ntries++) {
                        if (WPI_READ(sc, WPI_FH_RX_STATUS) &
                            WPI_FH_RX_STATUS_IDLE)
                                break;
                        DELAY(10);
                }
                wpi_nic_unlock(sc);
        }

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

static void
wpi_free_rx_ring(struct wpi_softc *sc)
{
        struct wpi_rx_ring *ring = &sc->rxq;
        int i;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        wpi_dma_contig_free(&ring->desc_dma);

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

                if (data->m != NULL) {
                        bus_dmamap_sync(ring->data_dmat, data->map,
                            BUS_DMASYNC_POSTREAD);
                        bus_dmamap_unload(ring->data_dmat, data->map);
                        m_freem(data->m);
                        data->m = NULL;
                }
                if (data->map != NULL)
                        bus_dmamap_destroy(ring->data_dmat, data->map);
        }
        if (ring->data_dmat != NULL) {
                bus_dma_tag_destroy(ring->data_dmat);
                ring->data_dmat = NULL;
        }
}

static int
wpi_alloc_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring, uint8_t qid)
{
        bus_addr_t paddr;
        bus_size_t size;
        int i, error;

        ring->qid = qid;
        ring->queued = 0;
        ring->cur = 0;
        ring->pending = 0;
        ring->update = 0;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /* Allocate TX descriptors (16KB aligned.) */
        size = WPI_TX_RING_COUNT * sizeof (struct wpi_tx_desc);
        error = wpi_dma_contig_alloc(sc, &ring->desc_dma, (void **)&ring->desc,
            size, WPI_RING_DMA_ALIGN);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not allocate TX ring DMA memory, error %d\n",
                    __func__, error);
                goto fail;
        }

        /* Update shared area with ring physical address. */
        sc->shared->txbase[qid] = htole32(ring->desc_dma.paddr);
        bus_dmamap_sync(sc->shared_dma.tag, sc->shared_dma.map,
            BUS_DMASYNC_PREWRITE);

        size = WPI_TX_RING_COUNT * sizeof (struct wpi_tx_cmd);
        error = wpi_dma_contig_alloc(sc, &ring->cmd_dma, (void **)&ring->cmd,
            size, 4);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not allocate TX cmd DMA memory, error %d\n",
                    __func__, error);
                goto fail;
        }

        error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev), 1, 0,
            BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES,
            WPI_MAX_SCATTER - 1, MCLBYTES, 0, NULL, NULL, &ring->data_dmat);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not create TX buf DMA tag, error %d\n",
                    __func__, error);
                goto fail;
        }

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

                data->cmd_paddr = paddr;
                paddr += sizeof (struct wpi_tx_cmd);

                error = bus_dmamap_create(ring->data_dmat, 0, &data->map);
                if (error != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not create TX buf DMA map, error %d\n",
                            __func__, error);
                        goto fail;
                }
        }

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;

fail:   wpi_free_tx_ring(sc, ring);
        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);
        return error;
}

static void
wpi_update_tx_ring(struct wpi_softc *sc, struct wpi_tx_ring *ring)
{
        WPI_WRITE(sc, WPI_HBUS_TARG_WRPTR, ring->qid << 8 | ring->cur);
}

static void
wpi_update_tx_ring_ps(struct wpi_softc *sc, struct wpi_tx_ring *ring)
{

        if (ring->update != 0) {
                /* Wait for INT_WAKEUP event. */
                return;
        }

        WPI_SETBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);
        if (WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_SLEEP) {
                DPRINTF(sc, WPI_DEBUG_PWRSAVE, "%s (%d): requesting wakeup\n",
                    __func__, ring->qid);
                ring->update = 1;
        } else {
                wpi_update_tx_ring(sc, ring);
                WPI_CLRBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);
        }
}

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

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

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

                if (data->m != NULL) {
                        bus_dmamap_sync(ring->data_dmat, data->map,
                            BUS_DMASYNC_POSTWRITE);
                        bus_dmamap_unload(ring->data_dmat, data->map);
                        m_freem(data->m);
                        data->m = NULL;
                }
                if (data->ni != NULL) {
                        ieee80211_free_node(data->ni);
                        data->ni = NULL;
                }
        }
        /* Clear TX descriptors. */
        memset(ring->desc, 0, ring->desc_dma.size);
        bus_dmamap_sync(ring->desc_dma.tag, ring->desc_dma.map,
            BUS_DMASYNC_PREWRITE);
        ring->queued = 0;
        ring->cur = 0;
        ring->pending = 0;
        ring->update = 0;
}

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

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

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

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

                if (data->m != NULL) {
                        bus_dmamap_sync(ring->data_dmat, data->map,
                            BUS_DMASYNC_POSTWRITE);
                        bus_dmamap_unload(ring->data_dmat, data->map);
                        m_freem(data->m);
                }
                if (data->map != NULL)
                        bus_dmamap_destroy(ring->data_dmat, data->map);
        }
        if (ring->data_dmat != NULL) {
                bus_dma_tag_destroy(ring->data_dmat);
                ring->data_dmat = NULL;
        }
}

/*
 * Extract various information from EEPROM.
 */
static int
wpi_read_eeprom(struct wpi_softc *sc, uint8_t macaddr[IEEE80211_ADDR_LEN])
{
#define WPI_CHK(res) do {               \
        if ((error = res) != 0)         \
                goto fail;              \
} while (0)
        uint8_t i;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /* Adapter has to be powered on for EEPROM access to work. */
        if ((error = wpi_apm_init(sc)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not power ON adapter, error %d\n", __func__,
                    error);
                return error;
        }

        if ((WPI_READ(sc, WPI_EEPROM_GP) & 0x6) == 0) {
                device_printf(sc->sc_dev, "bad EEPROM signature\n");
                error = EIO;
                goto fail;
        }
        /* Clear HW ownership of EEPROM. */
        WPI_CLRBITS(sc, WPI_EEPROM_GP, WPI_EEPROM_GP_IF_OWNER);

        /* Read the hardware capabilities, revision and SKU type. */
        WPI_CHK(wpi_read_prom_data(sc, WPI_EEPROM_SKU_CAP, &sc->cap,
            sizeof(sc->cap)));
        WPI_CHK(wpi_read_prom_data(sc, WPI_EEPROM_REVISION, &sc->rev,
            sizeof(sc->rev)));
        WPI_CHK(wpi_read_prom_data(sc, WPI_EEPROM_TYPE, &sc->type,
            sizeof(sc->type)));

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

        /* Read the regulatory domain (4 ASCII characters.) */
        WPI_CHK(wpi_read_prom_data(sc, WPI_EEPROM_DOMAIN, sc->domain,
            sizeof(sc->domain)));

        /* Read MAC address. */
        WPI_CHK(wpi_read_prom_data(sc, WPI_EEPROM_MAC, macaddr,
            IEEE80211_ADDR_LEN));

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

        /* Read the list of TX power groups. */
        for (i = 0; i < WPI_POWER_GROUPS_COUNT; i++)
                WPI_CHK(wpi_read_eeprom_group(sc, i));

fail:   wpi_apm_stop(sc);       /* Power OFF adapter. */

        DPRINTF(sc, WPI_DEBUG_TRACE, error ? TRACE_STR_END_ERR : TRACE_STR_END,
            __func__);

        return error;
#undef WPI_CHK
}

/*
 * Translate EEPROM flags to net80211.
 */
static uint32_t
wpi_eeprom_channel_flags(struct wpi_eeprom_chan *channel)
{
        uint32_t nflags;

        nflags = 0;
        if ((channel->flags & WPI_EEPROM_CHAN_ACTIVE) == 0)
                nflags |= IEEE80211_CHAN_PASSIVE;
        if ((channel->flags & WPI_EEPROM_CHAN_IBSS) == 0)
                nflags |= IEEE80211_CHAN_NOADHOC;
        if (channel->flags & WPI_EEPROM_CHAN_RADAR) {
                nflags |= IEEE80211_CHAN_DFS;
                /* XXX apparently IBSS may still be marked */
                nflags |= IEEE80211_CHAN_NOADHOC;
        }

        /* XXX HOSTAP uses WPI_MODE_IBSS */
        if (nflags & IEEE80211_CHAN_NOADHOC)
                nflags |= IEEE80211_CHAN_NOHOSTAP;

        return nflags;
}

static void
wpi_read_eeprom_band(struct wpi_softc *sc, uint8_t n, int maxchans,
    int *nchans, struct ieee80211_channel chans[])
{
        struct wpi_eeprom_chan *channels = sc->eeprom_channels[n];
        const struct wpi_chan_band *band = &wpi_bands[n];
        uint32_t nflags;
        uint8_t bands[IEEE80211_MODE_BYTES];
        uint8_t chan, i;
        int error;

        memset(bands, 0, sizeof(bands));

        if (n == 0) {
                setbit(bands, IEEE80211_MODE_11B);
                setbit(bands, IEEE80211_MODE_11G);
        } else
                setbit(bands, IEEE80211_MODE_11A);

        for (i = 0; i < band->nchan; i++) {
                if (!(channels[i].flags & WPI_EEPROM_CHAN_VALID)) {
                        DPRINTF(sc, WPI_DEBUG_EEPROM,
                            "Channel Not Valid: %d, band %d\n",
                             band->chan[i],n);
                        continue;
                }

                chan = band->chan[i];
                nflags = wpi_eeprom_channel_flags(&channels[i]);
                error = ieee80211_add_channel(chans, maxchans, nchans,
                    chan, 0, channels[i].maxpwr, nflags, bands);
                if (error != 0)
                        break;

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

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

/**
 * Read the eeprom to find out what channels are valid for the given
 * band and update net80211 with what we find.
 */
static int
wpi_read_eeprom_channels(struct wpi_softc *sc, uint8_t n)
{
        struct ieee80211com *ic = &sc->sc_ic;
        const struct wpi_chan_band *band = &wpi_bands[n];
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        error = wpi_read_prom_data(sc, band->addr, &sc->eeprom_channels[n],
            band->nchan * sizeof (struct wpi_eeprom_chan));
        if (error != 0) {
                DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);
                return error;
        }

        wpi_read_eeprom_band(sc, n, IEEE80211_CHAN_MAX, &ic->ic_nchans,
            ic->ic_channels);

        ieee80211_sort_channels(ic->ic_channels, ic->ic_nchans);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;
}

static struct wpi_eeprom_chan *
wpi_find_eeprom_channel(struct wpi_softc *sc, struct ieee80211_channel *c)
{
        int i, j;

        for (j = 0; j < WPI_CHAN_BANDS_COUNT; j++)
                for (i = 0; i < wpi_bands[j].nchan; i++)
                        if (wpi_bands[j].chan[i] == c->ic_ieee &&
                            ((j == 0) ^ IEEE80211_IS_CHAN_A(c)) == 1)
                                return &sc->eeprom_channels[j][i];

        return NULL;
}

static void
wpi_getradiocaps(struct ieee80211com *ic,
    int maxchans, int *nchans, struct ieee80211_channel chans[])
{
        struct wpi_softc *sc = ic->ic_softc;
        int i;

        /* Parse the list of authorized channels. */
        for (i = 0; i < WPI_CHAN_BANDS_COUNT && *nchans < maxchans; i++)
                wpi_read_eeprom_band(sc, i, maxchans, nchans, chans);
}

/*
 * Enforce flags read from EEPROM.
 */
static int
wpi_setregdomain(struct ieee80211com *ic, struct ieee80211_regdomain *rd,
    int nchan, struct ieee80211_channel chans[])
{
        struct wpi_softc *sc = ic->ic_softc;
        int i;

        for (i = 0; i < nchan; i++) {
                struct ieee80211_channel *c = &chans[i];
                struct wpi_eeprom_chan *channel;

                channel = wpi_find_eeprom_channel(sc, c);
                if (channel == NULL) {
                        ic_printf(ic, "%s: invalid channel %u freq %u/0x%x\n",
                            __func__, c->ic_ieee, c->ic_freq, c->ic_flags);
                        return EINVAL;
                }
                c->ic_flags |= wpi_eeprom_channel_flags(channel);
        }

        return 0;
}

static int
wpi_read_eeprom_group(struct wpi_softc *sc, uint8_t n)
{
        struct wpi_power_group *group = &sc->groups[n];
        struct wpi_eeprom_group rgroup;
        int i, error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        if ((error = wpi_read_prom_data(sc, WPI_EEPROM_POWER_GRP + n * 32,
            &rgroup, sizeof rgroup)) != 0) {
                DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);
                return error;
        }

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

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

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;
}

static __inline uint8_t
wpi_add_node_entry_adhoc(struct wpi_softc *sc)
{
        uint8_t newid = WPI_ID_IBSS_MIN;

        for (; newid <= WPI_ID_IBSS_MAX; newid++) {
                if ((sc->nodesmsk & (1 << newid)) == 0) {
                        sc->nodesmsk |= 1 << newid;
                        return newid;
                }
        }

        return WPI_ID_UNDEFINED;
}

static __inline uint8_t
wpi_add_node_entry_sta(struct wpi_softc *sc)
{
        sc->nodesmsk |= 1 << WPI_ID_BSS;

        return WPI_ID_BSS;
}

static __inline int
wpi_check_node_entry(struct wpi_softc *sc, uint8_t id)
{
        if (id == WPI_ID_UNDEFINED)
                return 0;

        return (sc->nodesmsk >> id) & 1;
}

static __inline void
wpi_clear_node_table(struct wpi_softc *sc)
{
        sc->nodesmsk = 0;
}

static __inline void
wpi_del_node_entry(struct wpi_softc *sc, uint8_t id)
{
        sc->nodesmsk &= ~(1 << id);
}

static struct ieee80211_node *
wpi_node_alloc(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN])
{
        struct wpi_node *wn;

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

        if (wn == NULL)
                return NULL;

        wn->id = WPI_ID_UNDEFINED;

        return &wn->ni;
}

static void
wpi_node_free(struct ieee80211_node *ni)
{
        struct wpi_softc *sc = ni->ni_ic->ic_softc;
        struct wpi_node *wn = WPI_NODE(ni);

        if (wn->id != WPI_ID_UNDEFINED) {
                WPI_NT_LOCK(sc);
                if (wpi_check_node_entry(sc, wn->id)) {
                        wpi_del_node_entry(sc, wn->id);
                        wpi_del_node(sc, ni);
                }
                WPI_NT_UNLOCK(sc);
        }

        sc->sc_node_free(ni);
}

static __inline int
wpi_check_bss_filter(struct wpi_softc *sc)
{
        return (sc->rxon.filter & htole32(WPI_FILTER_BSS)) != 0;
}

static void
wpi_ibss_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m, int subtype,
    const struct ieee80211_rx_stats *rxs,
    int rssi, int nf)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct wpi_softc *sc = vap->iv_ic->ic_softc;
        struct wpi_vap *wvp = WPI_VAP(vap);
        uint64_t ni_tstamp, rx_tstamp;

        wvp->wv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);

        if (vap->iv_state == IEEE80211_S_RUN &&
            (subtype == IEEE80211_FC0_SUBTYPE_BEACON ||
            subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)) {
                ni_tstamp = le64toh(ni->ni_tstamp.tsf);
                rx_tstamp = le64toh(sc->rx_tstamp);

                if (ni_tstamp >= rx_tstamp) {
                        DPRINTF(sc, WPI_DEBUG_STATE,
                            "ibss merge, tsf %ju tstamp %ju\n",
                            (uintmax_t)rx_tstamp, (uintmax_t)ni_tstamp);
                        (void) ieee80211_ibss_merge(ni);
                }
        }
}

static void
wpi_restore_node(void *arg, struct ieee80211_node *ni)
{
        struct wpi_softc *sc = arg;
        struct wpi_node *wn = WPI_NODE(ni);
        int error;

        WPI_NT_LOCK(sc);
        if (wn->id != WPI_ID_UNDEFINED) {
                wn->id = WPI_ID_UNDEFINED;
                if ((error = wpi_add_ibss_node(sc, ni)) != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not add IBSS node, error %d\n",
                            __func__, error);
                }
        }
        WPI_NT_UNLOCK(sc);
}

static void
wpi_restore_node_table(struct wpi_softc *sc, struct wpi_vap *wvp)
{
        struct ieee80211com *ic = &sc->sc_ic;

        /* Set group keys once. */
        WPI_NT_LOCK(sc);
        wvp->wv_gtk = 0;
        WPI_NT_UNLOCK(sc);

        ieee80211_iterate_nodes(&ic->ic_sta, wpi_restore_node, sc);
        ieee80211_crypto_reload_keys(ic);
}

/**
 * Called by net80211 when ever there is a change to 80211 state machine
 */
static int
wpi_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
{
        struct wpi_vap *wvp = WPI_VAP(vap);
        struct ieee80211com *ic = vap->iv_ic;
        struct wpi_softc *sc = ic->ic_softc;
        int error = 0;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        WPI_TXQ_LOCK(sc);
        if (nstate > IEEE80211_S_INIT && sc->sc_running == 0) {
                DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);
                WPI_TXQ_UNLOCK(sc);

                return ENXIO;
        }
        WPI_TXQ_UNLOCK(sc);

        DPRINTF(sc, WPI_DEBUG_STATE, "%s: %s -> %s\n", __func__,
                ieee80211_state_name[vap->iv_state],
                ieee80211_state_name[nstate]);

        if (vap->iv_state == IEEE80211_S_RUN && nstate < IEEE80211_S_RUN) {
                if ((error = wpi_set_pslevel(sc, 0, 0, 1)) != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not set power saving level\n",
                            __func__);
                        return error;
                }

                wpi_set_led(sc, WPI_LED_LINK, 1, 0);
        }

        switch (nstate) {
        case IEEE80211_S_SCAN:
                WPI_RXON_LOCK(sc);
                if (wpi_check_bss_filter(sc) != 0) {
                        sc->rxon.filter &= ~htole32(WPI_FILTER_BSS);
                        if ((error = wpi_send_rxon(sc, 0, 1)) != 0) {
                                device_printf(sc->sc_dev,
                                    "%s: could not send RXON\n", __func__);
                        }
                }
                WPI_RXON_UNLOCK(sc);
                break;

        case IEEE80211_S_ASSOC:
                if (vap->iv_state != IEEE80211_S_RUN)
                        break;
                /* FALLTHROUGH */
        case IEEE80211_S_AUTH:
                /*
                 * NB: do not optimize AUTH -> AUTH state transmission -
                 * this will break powersave with non-QoS AP!
                 */

                /*
                 * The node must be registered in the firmware before auth.
                 * Also the associd must be cleared on RUN -> ASSOC
                 * transitions.
                 */
                if ((error = wpi_auth(sc, vap)) != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not move to AUTH state, error %d\n",
                            __func__, error);
                }
                break;

        case IEEE80211_S_RUN:
                /*
                 * RUN -> RUN transition:
                 * STA mode: Just restart the timers.
                 * IBSS mode: Process IBSS merge.
                 */
                if (vap->iv_state == IEEE80211_S_RUN) {
                        if (vap->iv_opmode != IEEE80211_M_IBSS) {
                                WPI_RXON_LOCK(sc);
                                wpi_calib_timeout(sc);
                                WPI_RXON_UNLOCK(sc);
                                break;
                        } else {
                                /*
                                 * Drop the BSS_FILTER bit
                                 * (there is no another way to change bssid).
                                 */
                                WPI_RXON_LOCK(sc);
                                sc->rxon.filter &= ~htole32(WPI_FILTER_BSS);
                                if ((error = wpi_send_rxon(sc, 0, 1)) != 0) {
                                        device_printf(sc->sc_dev,
                                            "%s: could not send RXON\n",
                                            __func__);
                                }
                                WPI_RXON_UNLOCK(sc);

                                /* Restore all what was lost. */
                                wpi_restore_node_table(sc, wvp);

                                /* XXX set conditionally? */
                                wpi_updateedca(ic);
                        }
                }

                /*
                 * !RUN -> RUN requires setting the association id
                 * which is done with a firmware cmd.  We also defer
                 * starting the timers until that work is done.
                 */
                if ((error = wpi_run(sc, vap)) != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not move to RUN state\n", __func__);
                }
                break;

        default:
                break;
        }
        if (error != 0) {
                DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);
                return error;
        }

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return wvp->wv_newstate(vap, nstate, arg);
}

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

        if (wpi_check_bss_filter(sc) == 0)
                return;

        wpi_power_calibration(sc);

        callout_reset(&sc->calib_to, 60*hz, wpi_calib_timeout, sc);
}

static __inline uint8_t
rate2plcp(const uint8_t rate)
{
        switch (rate) {
        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;
        case 2:         return 10;
        case 4:         return 20;
        case 11:        return 55;
        case 22:        return 110;
        default:        return 0;
        }
}

static __inline uint8_t
plcp2rate(const uint8_t plcp)
{
        switch (plcp) {
        case 0xd:       return 12;
        case 0xf:       return 18;
        case 0x5:       return 24;
        case 0x7:       return 36;
        case 0x9:       return 48;
        case 0xb:       return 72;
        case 0x1:       return 96;
        case 0x3:       return 108;
        case 10:        return 2;
        case 20:        return 4;
        case 55:        return 11;
        case 110:       return 22;
        default:        return 0;
        }
}

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

static void
wpi_rx_done(struct wpi_softc *sc, struct wpi_rx_desc *desc,
    struct wpi_rx_data *data)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_rx_ring *ring = &sc->rxq;
        struct wpi_rx_stat *stat;
        struct wpi_rx_head *head;
        struct wpi_rx_tail *tail;
        struct ieee80211_frame *wh;
        struct ieee80211_node *ni;
        struct mbuf *m, *m1;
        bus_addr_t paddr;
        uint32_t flags;
        uint16_t len;
        int error;

        stat = (struct wpi_rx_stat *)(desc + 1);

        if (__predict_false(stat->len > WPI_STAT_MAXLEN)) {
                device_printf(sc->sc_dev, "invalid RX statistic header\n");
                goto fail1;
        }

        bus_dmamap_sync(ring->data_dmat, data->map, BUS_DMASYNC_POSTREAD);
        head = (struct wpi_rx_head *)((caddr_t)(stat + 1) + stat->len);
        len = le16toh(head->len);
        tail = (struct wpi_rx_tail *)((caddr_t)(head + 1) + len);
        flags = le32toh(tail->flags);

        DPRINTF(sc, WPI_DEBUG_RECV, "%s: idx %d len %d stat len %u rssi %d"
            " rate %x chan %d tstamp %ju\n", __func__, ring->cur,
            le32toh(desc->len), len, (int8_t)stat->rssi,
            head->plcp, head->chan, (uintmax_t)le64toh(tail->tstamp));

        /* Discard frames with a bad FCS early. */
        if ((flags & WPI_RX_NOERROR) != WPI_RX_NOERROR) {
                DPRINTF(sc, WPI_DEBUG_RECV, "%s: RX flags error %x\n",
                    __func__, flags);
                goto fail1;
        }
        /* Discard frames that are too short. */
        if (len < sizeof (struct ieee80211_frame_ack)) {
                DPRINTF(sc, WPI_DEBUG_RECV, "%s: frame too short: %d\n",
                    __func__, len);
                goto fail1;
        }

        m1 = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUMPAGESIZE);
        if (__predict_false(m1 == NULL)) {
                DPRINTF(sc, WPI_DEBUG_ANY, "%s: no mbuf to restock ring\n",
                    __func__);
                goto fail1;
        }
        bus_dmamap_unload(ring->data_dmat, data->map);

        error = bus_dmamap_load(ring->data_dmat, data->map, mtod(m1, void *),
            MJUMPAGESIZE, wpi_dma_map_addr, &paddr, BUS_DMA_NOWAIT);
        if (__predict_false(error != 0 && error != EFBIG)) {
                device_printf(sc->sc_dev,
                    "%s: bus_dmamap_load failed, error %d\n", __func__, error);
                m_freem(m1);

                /* Try to reload the old mbuf. */
                error = bus_dmamap_load(ring->data_dmat, data->map,
                    mtod(data->m, void *), MJUMPAGESIZE, wpi_dma_map_addr,
                    &paddr, BUS_DMA_NOWAIT);
                if (error != 0 && error != EFBIG) {
                        panic("%s: could not load old RX mbuf", __func__);
                }
                /* Physical address may have changed. */
                ring->desc[ring->cur] = htole32(paddr);
                bus_dmamap_sync(ring->data_dmat, ring->desc_dma.map,
                    BUS_DMASYNC_PREWRITE);
                goto fail1;
        }

        m = data->m;
        data->m = m1;
        /* Update RX descriptor. */
        ring->desc[ring->cur] = htole32(paddr);
        bus_dmamap_sync(ring->desc_dma.tag, ring->desc_dma.map,
            BUS_DMASYNC_PREWRITE);

        /* Finalize mbuf. */
        m->m_data = (caddr_t)(head + 1);
        m->m_pkthdr.len = m->m_len = len;

        /* Grab a reference to the source node. */
        wh = mtod(m, struct ieee80211_frame *);

        if ((wh->i_fc[1] & IEEE80211_FC1_PROTECTED) &&
            (flags & WPI_RX_CIPHER_MASK) == WPI_RX_CIPHER_CCMP) {
                /* Check whether decryption was successful or not. */
                if ((flags & WPI_RX_DECRYPT_MASK) != WPI_RX_DECRYPT_OK) {
                        DPRINTF(sc, WPI_DEBUG_RECV,
                            "CCMP decryption failed 0x%x\n", flags);
                        goto fail2;
                }
                m->m_flags |= M_WEP;
        }

        if (len >= sizeof(struct ieee80211_frame_min))
                ni = ieee80211_find_rxnode(ic, (struct ieee80211_frame_min *)wh);
        else
                ni = NULL;

        sc->rx_tstamp = tail->tstamp;

        if (ieee80211_radiotap_active(ic)) {
                struct wpi_rx_radiotap_header *tap = &sc->sc_rxtap;

                tap->wr_flags = 0;
                if (head->flags & htole16(WPI_STAT_FLAG_SHPREAMBLE))
                        tap->wr_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
                tap->wr_dbm_antsignal = (int8_t)(stat->rssi + WPI_RSSI_OFFSET);
                tap->wr_dbm_antnoise = WPI_RSSI_OFFSET;
                tap->wr_tsft = tail->tstamp;
                tap->wr_antenna = (le16toh(head->flags) >> 4) & 0xf;
                tap->wr_rate = plcp2rate(head->plcp);
        }

        WPI_UNLOCK(sc);

        /* Send the frame to the 802.11 layer. */
        if (ni != NULL) {
                (void)ieee80211_input(ni, m, stat->rssi, WPI_RSSI_OFFSET);
                /* Node is no longer needed. */
                ieee80211_free_node(ni);
        } else
                (void)ieee80211_input_all(ic, m, stat->rssi, WPI_RSSI_OFFSET);

        WPI_LOCK(sc);

        return;

fail2:  m_freem(m);

fail1:  counter_u64_add(ic->ic_ierrors, 1);
}

static void
wpi_rx_statistics(struct wpi_softc *sc, struct wpi_rx_desc *desc,
    struct wpi_rx_data *data)
{
        /* Ignore */
}

static void
wpi_tx_done(struct wpi_softc *sc, struct wpi_rx_desc *desc)
{
        struct ieee80211_ratectl_tx_status *txs = &sc->sc_txs;
        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 mbuf *m;
        struct ieee80211_node *ni;
        uint32_t status = le32toh(stat->status);

        KASSERT(data->ni != NULL, ("no node"));
        KASSERT(data->m != NULL, ("no mbuf"));

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        DPRINTF(sc, WPI_DEBUG_XMIT, "%s: "
            "qid %d idx %d retries %d btkillcnt %d rate %x duration %d "
            "status %x\n", __func__, desc->qid, desc->idx, stat->ackfailcnt,
            stat->btkillcnt, stat->rate, le32toh(stat->duration), status);

        /* Unmap and free mbuf. */
        bus_dmamap_sync(ring->data_dmat, data->map, BUS_DMASYNC_POSTWRITE);
        bus_dmamap_unload(ring->data_dmat, data->map);
        m = data->m, data->m = NULL;
        ni = data->ni, data->ni = NULL;

        /* Restore frame header. */
        KASSERT(M_LEADINGSPACE(m) >= data->hdrlen, ("no frame header!"));
        M_PREPEND(m, data->hdrlen, M_NOWAIT);
        KASSERT(m != NULL, ("%s: m is NULL\n", __func__));

        /*
         * Update rate control statistics for the node.
         */
        txs->pktlen = m->m_pkthdr.len;
        txs->short_retries = stat->rtsfailcnt;
        txs->long_retries = stat->ackfailcnt / WPI_NTRIES_DEFAULT;
        if (!(status & WPI_TX_STATUS_FAIL))
                txs->status = IEEE80211_RATECTL_TX_SUCCESS;
        else {
                switch (status & 0xff) {
                case WPI_TX_STATUS_FAIL_SHORT_LIMIT:
                        txs->status = IEEE80211_RATECTL_TX_FAIL_SHORT;
                        break;
                case WPI_TX_STATUS_FAIL_LONG_LIMIT:
                        txs->status = IEEE80211_RATECTL_TX_FAIL_LONG;
                        break;
                case WPI_TX_STATUS_FAIL_LIFE_EXPIRE:
                        txs->status = IEEE80211_RATECTL_TX_FAIL_EXPIRED;
                        break;
                default:
                        txs->status = IEEE80211_RATECTL_TX_FAIL_UNSPECIFIED;
                        break;
                }
        }

        ieee80211_ratectl_tx_complete(ni, txs);
        ieee80211_tx_complete(ni, m, (status & WPI_TX_STATUS_FAIL) != 0);

        WPI_TXQ_STATE_LOCK(sc);
        if (--ring->queued > 0)
                callout_reset(&sc->tx_timeout, 5*hz, wpi_tx_timeout, sc);
        else
                callout_stop(&sc->tx_timeout);
        WPI_TXQ_STATE_UNLOCK(sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);
}

/*
 * Process a "command done" firmware notification.  This is where we wakeup
 * processes waiting for a synchronous command completion.
 */
static void
wpi_cmd_done(struct wpi_softc *sc, struct wpi_rx_desc *desc)
{
        struct wpi_tx_ring *ring = &sc->txq[WPI_CMD_QUEUE_NUM];
        struct wpi_tx_data *data;
        struct wpi_tx_cmd *cmd;

        DPRINTF(sc, WPI_DEBUG_CMD, "cmd notification qid %x idx %d flags %x "
                                   "type %s len %d\n", desc->qid, desc->idx,
                                   desc->flags, wpi_cmd_str(desc->type),
                                   le32toh(desc->len));

        if ((desc->qid & WPI_RX_DESC_QID_MSK) != WPI_CMD_QUEUE_NUM)
                return; /* Not a command ack. */

        KASSERT(ring->queued == 0, ("ring->queued must be 0"));

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

        /* If the command was mapped in an mbuf, free it. */
        if (data->m != NULL) {
                bus_dmamap_sync(ring->data_dmat, data->map,
                    BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(ring->data_dmat, data->map);
                m_freem(data->m);
                data->m = NULL;
        }

        wakeup(cmd);

        if (desc->type == WPI_CMD_SET_POWER_MODE) {
                struct wpi_pmgt_cmd *pcmd = (struct wpi_pmgt_cmd *)cmd->data;

                bus_dmamap_sync(ring->data_dmat, ring->cmd_dma.map,
                    BUS_DMASYNC_POSTREAD);

                WPI_TXQ_LOCK(sc);
                if (le16toh(pcmd->flags) & WPI_PS_ALLOW_SLEEP) {
                        sc->sc_update_rx_ring = wpi_update_rx_ring_ps;
                        sc->sc_update_tx_ring = wpi_update_tx_ring_ps;
                } else {
                        sc->sc_update_rx_ring = wpi_update_rx_ring;
                        sc->sc_update_tx_ring = wpi_update_tx_ring;
                }
                WPI_TXQ_UNLOCK(sc);
        }
}

static void
wpi_notif_intr(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);
        uint32_t hw;

        bus_dmamap_sync(sc->shared_dma.tag, sc->shared_dma.map,
            BUS_DMASYNC_POSTREAD);

        hw = le32toh(sc->shared->next) & 0xfff;
        hw = (hw == 0) ? WPI_RX_RING_COUNT - 1 : hw - 1;

        while (sc->rxq.cur != hw) {
                sc->rxq.cur = (sc->rxq.cur + 1) % WPI_RX_RING_COUNT;

                struct wpi_rx_data *data = &sc->rxq.data[sc->rxq.cur];
                struct wpi_rx_desc *desc;

                bus_dmamap_sync(sc->rxq.data_dmat, data->map,
                    BUS_DMASYNC_POSTREAD);
                desc = mtod(data->m, struct wpi_rx_desc *);

                DPRINTF(sc, WPI_DEBUG_NOTIFY,
                    "%s: cur=%d; qid %x idx %d flags %x type %d(%s) len %d\n",
                    __func__, sc->rxq.cur, desc->qid, desc->idx, desc->flags,
                    desc->type, wpi_cmd_str(desc->type), le32toh(desc->len));

                if (!(desc->qid & WPI_UNSOLICITED_RX_NOTIF)) {
                        /* Reply to a command. */
                        wpi_cmd_done(sc, desc);
                }

                switch (desc->type) {
                case WPI_RX_DONE:
                        /* An 802.11 frame has been received. */
                        wpi_rx_done(sc, desc, data);

                        if (__predict_false(sc->sc_running == 0)) {
                                /* wpi_stop() was called. */
                                return;
                        }

                        break;

                case WPI_TX_DONE:
                        /* An 802.11 frame has been transmitted. */
                        wpi_tx_done(sc, desc);
                        break;

                case WPI_RX_STATISTICS:
                case WPI_BEACON_STATISTICS:
                        wpi_rx_statistics(sc, desc, data);
                        break;

                case WPI_BEACON_MISSED:
                {
                        struct wpi_beacon_missed *miss =
                            (struct wpi_beacon_missed *)(desc + 1);
                        uint32_t expected, misses, received, threshold;

                        bus_dmamap_sync(sc->rxq.data_dmat, data->map,
                            BUS_DMASYNC_POSTREAD);

                        misses = le32toh(miss->consecutive);
                        expected = le32toh(miss->expected);
                        received = le32toh(miss->received);
                        threshold = MAX(2, vap->iv_bmissthreshold);

                        DPRINTF(sc, WPI_DEBUG_BMISS,
                            "%s: beacons missed %u(%u) (received %u/%u)\n",
                            __func__, misses, le32toh(miss->total), received,
                            expected);

                        if (misses >= threshold ||
                            (received == 0 && expected >= threshold)) {
                                WPI_RXON_LOCK(sc);
                                if (callout_pending(&sc->scan_timeout)) {
                                        wpi_cmd(sc, WPI_CMD_SCAN_ABORT, NULL,
                                            0, 1);
                                }
                                WPI_RXON_UNLOCK(sc);
                                if (vap->iv_state == IEEE80211_S_RUN &&
                                    (ic->ic_flags & IEEE80211_F_SCAN) == 0)
                                        ieee80211_beacon_miss(ic);
                        }

                        break;
                }
#ifdef WPI_DEBUG
                case WPI_BEACON_SENT:
                {
                        struct wpi_tx_stat *stat =
                            (struct wpi_tx_stat *)(desc + 1);
                        uint64_t *tsf = (uint64_t *)(stat + 1);
                        uint32_t *mode = (uint32_t *)(tsf + 1);

                        bus_dmamap_sync(sc->rxq.data_dmat, data->map,
                            BUS_DMASYNC_POSTREAD);

                        DPRINTF(sc, WPI_DEBUG_BEACON,
                            "beacon sent: rts %u, ack %u, btkill %u, rate %u, "
                            "duration %u, status %x, tsf %ju, mode %x\n",
                            stat->rtsfailcnt, stat->ackfailcnt,
                            stat->btkillcnt, stat->rate, le32toh(stat->duration),
                            le32toh(stat->status), le64toh(*tsf),
                            le32toh(*mode));

                        break;
                }
#endif
                case WPI_UC_READY:
                {
                        struct wpi_ucode_info *uc =
                            (struct wpi_ucode_info *)(desc + 1);

                        /* The microcontroller is ready. */
                        bus_dmamap_sync(sc->rxq.data_dmat, data->map,
                            BUS_DMASYNC_POSTREAD);
                        DPRINTF(sc, WPI_DEBUG_RESET,
                            "microcode alive notification version=%d.%d "
                            "subtype=%x alive=%x\n", uc->major, uc->minor,
                            uc->subtype, le32toh(uc->valid));

                        if (le32toh(uc->valid) != 1) {
                                device_printf(sc->sc_dev,
                                    "microcontroller initialization failed\n");
                                wpi_stop_locked(sc);
                                return;
                        }
                        /* Save the address of the error log in SRAM. */
                        sc->errptr = le32toh(uc->errptr);
                        break;
                }
                case WPI_STATE_CHANGED:
                {
                        bus_dmamap_sync(sc->rxq.data_dmat, data->map,
                            BUS_DMASYNC_POSTREAD);

                        uint32_t *status = (uint32_t *)(desc + 1);

                        DPRINTF(sc, WPI_DEBUG_STATE, "state changed to %x\n",
                            le32toh(*status));

                        if (le32toh(*status) & 1) {
                                WPI_NT_LOCK(sc);
                                wpi_clear_node_table(sc);
                                WPI_NT_UNLOCK(sc);
                                ieee80211_runtask(ic,
                                    &sc->sc_radiooff_task);
                                return;
                        }
                        break;
                }
#ifdef WPI_DEBUG
                case WPI_START_SCAN:
                {
                        bus_dmamap_sync(sc->rxq.data_dmat, data->map,
                            BUS_DMASYNC_POSTREAD);

                        struct wpi_start_scan *scan =
                            (struct wpi_start_scan *)(desc + 1);
                        DPRINTF(sc, WPI_DEBUG_SCAN,
                            "%s: scanning channel %d status %x\n",
                            __func__, scan->chan, le32toh(scan->status));

                        break;
                }
#endif
                case WPI_STOP_SCAN:
                {
                        bus_dmamap_sync(sc->rxq.data_dmat, data->map,
                            BUS_DMASYNC_POSTREAD);

                        struct wpi_stop_scan *scan =
                            (struct wpi_stop_scan *)(desc + 1);

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

                        WPI_RXON_LOCK(sc);
                        callout_stop(&sc->scan_timeout);
                        WPI_RXON_UNLOCK(sc);
                        if (scan->status == WPI_SCAN_ABORTED)
                                ieee80211_cancel_scan(vap);
                        else
                                ieee80211_scan_next(vap);
                        break;
                }
                }

                if (sc->rxq.cur % 8 == 0) {
                        /* Tell the firmware what we have processed. */
                        sc->sc_update_rx_ring(sc);
                }
        }
}

/*
 * Process an INT_WAKEUP interrupt raised when the microcontroller wakes up
 * from power-down sleep mode.
 */
static void
wpi_wakeup_intr(struct wpi_softc *sc)
{
        int qid;

        DPRINTF(sc, WPI_DEBUG_PWRSAVE,
            "%s: ucode wakeup from power-down sleep\n", __func__);

        /* Wakeup RX and TX rings. */
        if (sc->rxq.update) {
                sc->rxq.update = 0;
                wpi_update_rx_ring(sc);
        }
        WPI_TXQ_LOCK(sc);
        for (qid = 0; qid < WPI_DRV_NTXQUEUES; qid++) {
                struct wpi_tx_ring *ring = &sc->txq[qid];

                if (ring->update) {
                        ring->update = 0;
                        wpi_update_tx_ring(sc, ring);
                }
        }
        WPI_CLRBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_MAC_ACCESS_REQ);
        WPI_TXQ_UNLOCK(sc);
}

/*
 * This function prints firmware registers
 */
#ifdef WPI_DEBUG
static void
wpi_debug_registers(struct wpi_softc *sc)
{
        size_t i;
        static const uint32_t csr_tbl[] = {
                WPI_HW_IF_CONFIG,
                WPI_INT,
                WPI_INT_MASK,
                WPI_FH_INT,
                WPI_GPIO_IN,
                WPI_RESET,
                WPI_GP_CNTRL,
                WPI_EEPROM,
                WPI_EEPROM_GP,
                WPI_GIO,
                WPI_UCODE_GP1,
                WPI_UCODE_GP2,
                WPI_GIO_CHICKEN,
                WPI_ANA_PLL,
                WPI_DBG_HPET_MEM,
        };
        static const uint32_t prph_tbl[] = {
                WPI_APMG_CLK_CTRL,
                WPI_APMG_PS,
                WPI_APMG_PCI_STT,
                WPI_APMG_RFKILL,
        };

        DPRINTF(sc, WPI_DEBUG_REGISTER,"%s","\n");

        for (i = 0; i < nitems(csr_tbl); i++) {
                DPRINTF(sc, WPI_DEBUG_REGISTER, "  %-18s: 0x%08x ",
                    wpi_get_csr_string(csr_tbl[i]), WPI_READ(sc, csr_tbl[i]));

                if ((i + 1) % 2 == 0)
                        DPRINTF(sc, WPI_DEBUG_REGISTER, "\n");
        }
        DPRINTF(sc, WPI_DEBUG_REGISTER, "\n\n");

        if (wpi_nic_lock(sc) == 0) {
                for (i = 0; i < nitems(prph_tbl); i++) {
                        DPRINTF(sc, WPI_DEBUG_REGISTER, "  %-18s: 0x%08x ",
                            wpi_get_prph_string(prph_tbl[i]),
                            wpi_prph_read(sc, prph_tbl[i]));

                        if ((i + 1) % 2 == 0)
                                DPRINTF(sc, WPI_DEBUG_REGISTER, "\n");
                }
                DPRINTF(sc, WPI_DEBUG_REGISTER, "\n");
                wpi_nic_unlock(sc);
        } else {
                DPRINTF(sc, WPI_DEBUG_REGISTER,
                    "Cannot access internal registers.\n");
        }
}
#endif

/*
 * Dump the error log of the firmware when a firmware panic occurs.  Although
 * we can't debug the firmware because it is neither open source nor free, it
 * can help us to identify certain classes of problems.
 */
static void
wpi_fatal_intr(struct wpi_softc *sc)
{
        struct wpi_fw_dump dump;
        uint32_t i, offset, count;

        /* Check that the error log address is valid. */
        if (sc->errptr < WPI_FW_DATA_BASE ||
            sc->errptr + sizeof (dump) >
            WPI_FW_DATA_BASE + WPI_FW_DATA_MAXSZ) {
                printf("%s: bad firmware error log address 0x%08x\n", __func__,
                    sc->errptr);
                return;
        }
        if (wpi_nic_lock(sc) != 0) {
                printf("%s: could not read firmware error log\n", __func__);
                return;
        }
        /* Read number of entries in the log. */
        count = wpi_mem_read(sc, sc->errptr);
        if (count == 0 || count * sizeof (dump) > WPI_FW_DATA_MAXSZ) {
                printf("%s: invalid count field (count = %u)\n", __func__,
                    count);
                wpi_nic_unlock(sc);
                return;
        }
        /* Skip "count" field. */
        offset = sc->errptr + sizeof (uint32_t);
        printf("firmware error log (count = %u):\n", count);
        for (i = 0; i < count; i++) {
                wpi_mem_read_region_4(sc, offset, (uint32_t *)&dump,
                    sizeof (dump) / sizeof (uint32_t));

                printf("  error type = \"%s\" (0x%08X)\n",
                    (dump.desc < nitems(wpi_fw_errmsg)) ?
                        wpi_fw_errmsg[dump.desc] : "UNKNOWN",
                    dump.desc);
                printf("  error data      = 0x%08X\n",
                    dump.data);
                printf("  branch link     = 0x%08X%08X\n",
                    dump.blink[0], dump.blink[1]);
                printf("  interrupt link  = 0x%08X%08X\n",
                    dump.ilink[0], dump.ilink[1]);
                printf("  time            = %u\n", dump.time);

                offset += sizeof (dump);
        }
        wpi_nic_unlock(sc);
        /* Dump driver status (TX and RX rings) while we're here. */
        printf("driver status:\n");
        WPI_TXQ_LOCK(sc);
        for (i = 0; i < WPI_DRV_NTXQUEUES; i++) {
                struct wpi_tx_ring *ring = &sc->txq[i];
                printf("  tx ring %2d: qid=%-2d cur=%-3d queued=%-3d\n",
                    i, ring->qid, ring->cur, ring->queued);
        }
        WPI_TXQ_UNLOCK(sc);
        printf("  rx ring: cur=%d\n", sc->rxq.cur);
}

static void
wpi_intr(void *arg)
{
        struct wpi_softc *sc = arg;
        uint32_t r1, r2;

        WPI_LOCK(sc);

        /* Disable interrupts. */
        WPI_WRITE(sc, WPI_INT_MASK, 0);

        r1 = WPI_READ(sc, WPI_INT);

        if (__predict_false(r1 == 0xffffffff ||
                           (r1 & 0xfffffff0) == 0xa5a5a5a0))
                goto end;       /* Hardware gone! */

        r2 = WPI_READ(sc, WPI_FH_INT);

        DPRINTF(sc, WPI_DEBUG_INTR, "%s: reg1=0x%08x reg2=0x%08x\n", __func__,
            r1, r2);

        if (r1 == 0 && r2 == 0)
                goto done;      /* Interrupt not for us. */

        /* Acknowledge interrupts. */
        WPI_WRITE(sc, WPI_INT, r1);
        WPI_WRITE(sc, WPI_FH_INT, r2);

        if (__predict_false(r1 & (WPI_INT_SW_ERR | WPI_INT_HW_ERR))) {
                struct ieee80211com *ic = &sc->sc_ic;

                device_printf(sc->sc_dev, "fatal firmware error\n");
#ifdef WPI_DEBUG
                wpi_debug_registers(sc);
#endif
                wpi_fatal_intr(sc);
                DPRINTF(sc, WPI_DEBUG_HW,
                    "(%s)\n", (r1 & WPI_INT_SW_ERR) ? "(Software Error)" :
                    "(Hardware Error)");
                ieee80211_restart_all(ic);
                goto end;
        }

        if ((r1 & (WPI_INT_FH_RX | WPI_INT_SW_RX)) ||
            (r2 & WPI_FH_INT_RX))
                wpi_notif_intr(sc);

        if (r1 & WPI_INT_ALIVE)
                wakeup(sc);     /* Firmware is alive. */

        if (r1 & WPI_INT_WAKEUP)
                wpi_wakeup_intr(sc);

done:
        /* Re-enable interrupts. */
        if (__predict_true(sc->sc_running))
                WPI_WRITE(sc, WPI_INT_MASK, WPI_INT_MASK_DEF);

end:    WPI_UNLOCK(sc);
}

static void
wpi_free_txfrags(struct wpi_softc *sc, uint16_t ac)
{
        struct wpi_tx_ring *ring;
        struct wpi_tx_data *data;
        uint8_t cur;

        WPI_TXQ_LOCK(sc);
        ring = &sc->txq[ac];

        while (ring->pending != 0) {
                ring->pending--;
                cur = (ring->cur + ring->pending) % WPI_TX_RING_COUNT;
                data = &ring->data[cur];

                bus_dmamap_sync(ring->data_dmat, data->map,
                    BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(ring->data_dmat, data->map);
                m_freem(data->m);
                data->m = NULL;

                ieee80211_node_decref(data->ni);
                data->ni = NULL;
        }

        WPI_TXQ_UNLOCK(sc);
}

static int
wpi_cmd2(struct wpi_softc *sc, struct wpi_buf *buf)
{
        struct ieee80211_frame *wh;
        struct wpi_tx_cmd *cmd;
        struct wpi_tx_data *data;
        struct wpi_tx_desc *desc;
        struct wpi_tx_ring *ring;
        struct mbuf *m1;
        bus_dma_segment_t *seg, segs[WPI_MAX_SCATTER];
        uint8_t cur, pad;
        uint16_t hdrlen;
        int error, i, nsegs, totlen, frag;

        WPI_TXQ_LOCK(sc);

        KASSERT(buf->size <= sizeof(buf->data), ("buffer overflow"));

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        if (__predict_false(sc->sc_running == 0)) {
                /* wpi_stop() was called */
                error = ENETDOWN;
                goto end;
        }

        wh = mtod(buf->m, struct ieee80211_frame *);
        hdrlen = ieee80211_anyhdrsize(wh);
        totlen = buf->m->m_pkthdr.len;
        frag = ((buf->m->m_flags & (M_FRAG | M_LASTFRAG)) == M_FRAG);

        if (__predict_false(totlen < sizeof(struct ieee80211_frame_min))) {
                error = EINVAL;
                goto end;
        }

        if (hdrlen & 3) {
                /* First segment length must be a multiple of 4. */
                pad = 4 - (hdrlen & 3);
        } else
                pad = 0;

        ring = &sc->txq[buf->ac];
        cur = (ring->cur + ring->pending) % WPI_TX_RING_COUNT;
        desc = &ring->desc[cur];
        data = &ring->data[cur];

        /* Prepare TX firmware command. */
        cmd = &ring->cmd[cur];
        cmd->code = buf->code;
        cmd->flags = 0;
        cmd->qid = ring->qid;
        cmd->idx = cur;

        memcpy(cmd->data, buf->data, buf->size);

        /* Save and trim IEEE802.11 header. */
        memcpy((uint8_t *)(cmd->data + buf->size), wh, hdrlen);
        m_adj(buf->m, hdrlen);

        error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map, buf->m,
            segs, &nsegs, BUS_DMA_NOWAIT);
        if (error != 0 && error != EFBIG) {
                device_printf(sc->sc_dev,
                    "%s: can't map mbuf (error %d)\n", __func__, error);
                goto end;
        }
        if (error != 0) {
                /* Too many DMA segments, linearize mbuf. */
                m1 = m_collapse(buf->m, M_NOWAIT, WPI_MAX_SCATTER - 1);
                if (m1 == NULL) {
                        device_printf(sc->sc_dev,
                            "%s: could not defrag mbuf\n", __func__);
                        error = ENOBUFS;
                        goto end;
                }
                buf->m = m1;

                error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map,
                    buf->m, segs, &nsegs, BUS_DMA_NOWAIT);
                if (__predict_false(error != 0)) {
                        /* XXX fix this (applicable to the iwn(4) too) */
                        /*
                         * NB: Do not return error;
                         * original mbuf does not exist anymore.
                         */
                        device_printf(sc->sc_dev,
                            "%s: can't map mbuf (error %d)\n", __func__,
                            error);
                        if (ring->qid < WPI_CMD_QUEUE_NUM) {
                                if_inc_counter(buf->ni->ni_vap->iv_ifp,
                                    IFCOUNTER_OERRORS, 1);
                                if (!frag)
                                        ieee80211_free_node(buf->ni);
                        }
                        m_freem(buf->m);
                        error = 0;
                        goto end;
                }
        }

        KASSERT(nsegs < WPI_MAX_SCATTER,
            ("too many DMA segments, nsegs (%d) should be less than %d",
             nsegs, WPI_MAX_SCATTER));

        data->m = buf->m;
        data->ni = buf->ni;
        data->hdrlen = hdrlen;

        DPRINTF(sc, WPI_DEBUG_XMIT, "%s: qid %d idx %d len %d nsegs %d\n",
            __func__, ring->qid, cur, totlen, nsegs);

        /* Fill TX descriptor. */
        desc->nsegs = WPI_PAD32(totlen + pad) << 4 | (1 + nsegs);
        /* First DMA segment is used by the TX command. */
        desc->segs[0].addr = htole32(data->cmd_paddr);
        desc->segs[0].len  = htole32(4 + buf->size + hdrlen + pad);
        /* Other DMA segments are for data payload. */
        seg = &segs[0];
        for (i = 1; i <= nsegs; i++) {
                desc->segs[i].addr = htole32(seg->ds_addr);
                desc->segs[i].len  = htole32(seg->ds_len);
                seg++;
        }

        bus_dmamap_sync(ring->data_dmat, data->map, BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(ring->data_dmat, ring->cmd_dma.map,
            BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(ring->desc_dma.tag, ring->desc_dma.map,
            BUS_DMASYNC_PREWRITE);

        ring->pending += 1;

        if (!frag) {
                if (ring->qid < WPI_CMD_QUEUE_NUM) {
                        WPI_TXQ_STATE_LOCK(sc);
                        ring->queued += ring->pending;
                        callout_reset(&sc->tx_timeout, 5*hz, wpi_tx_timeout,
                            sc);
                        WPI_TXQ_STATE_UNLOCK(sc);
                }

                /* Kick TX ring. */
                ring->cur = (ring->cur + ring->pending) % WPI_TX_RING_COUNT;
                ring->pending = 0;
                sc->sc_update_tx_ring(sc, ring);
        } else
                (void) ieee80211_ref_node(data->ni);

end:    DPRINTF(sc, WPI_DEBUG_TRACE, error ? TRACE_STR_END_ERR : TRACE_STR_END,
            __func__);

        WPI_TXQ_UNLOCK(sc);

        return (error);
}

/*
 * Construct the data packet for a transmit buffer.
 */
static int
wpi_tx_data(struct wpi_softc *sc, struct mbuf *m, struct ieee80211_node *ni)
{
        const struct ieee80211_txparam *tp = ni->ni_txparms;
        struct ieee80211vap *vap = ni->ni_vap;
        struct ieee80211com *ic = ni->ni_ic;
        struct wpi_node *wn = WPI_NODE(ni);
        struct ieee80211_frame *wh;
        struct ieee80211_key *k = NULL;
        struct wpi_buf tx_data;
        struct wpi_cmd_data *tx = (struct wpi_cmd_data *)&tx_data.data;
        uint32_t flags;
        uint16_t ac, qos;
        uint8_t tid, type, rate;
        int swcrypt, ismcast, totlen;

        wh = mtod(m, struct ieee80211_frame *);
        type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
        ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
        swcrypt = 1;

        /* Select EDCA Access Category and TX ring for this frame. */
        if (IEEE80211_QOS_HAS_SEQ(wh)) {
                qos = ((const struct ieee80211_qosframe *)wh)->i_qos[0];
                tid = qos & IEEE80211_QOS_TID;
        } else {
                qos = 0;
                tid = 0;
        }
        ac = M_WME_GETAC(m);

        /* Choose a TX rate index. */
        if (type == IEEE80211_FC0_TYPE_MGT ||
            type == IEEE80211_FC0_TYPE_CTL ||
            (m->m_flags & M_EAPOL) != 0)
                rate = tp->mgmtrate;
        else if (ismcast)
                rate = tp->mcastrate;
        else if (tp->ucastrate != IEEE80211_FIXED_RATE_NONE)
                rate = tp->ucastrate;
        else {
                /* XXX pass pktlen */
                (void) ieee80211_ratectl_rate(ni, NULL, 0);
                rate = ieee80211_node_get_txrate_dot11rate(ni);
        }

        /* Encrypt the frame if need be. */
        if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
                /* Retrieve key for TX. */
                k = ieee80211_crypto_encap(ni, m);
                if (k == NULL)
                        return (ENOBUFS);

                swcrypt = k->wk_flags & IEEE80211_KEY_SWCRYPT;

                /* 802.11 header may have moved. */
                wh = mtod(m, struct ieee80211_frame *);
        }
        totlen = m->m_pkthdr.len;

        if (ieee80211_radiotap_active_vap(vap)) {
                struct wpi_tx_radiotap_header *tap = &sc->sc_txtap;

                tap->wt_flags = 0;
                tap->wt_rate = rate;
                if (k != NULL)
                        tap->wt_flags |= IEEE80211_RADIOTAP_F_WEP;
                if (wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG)
                        tap->wt_flags |= IEEE80211_RADIOTAP_F_FRAG;

                ieee80211_radiotap_tx(vap, m);
        }

        flags = 0;
        if (!ismcast) {
                /* Unicast frame, check if an ACK is expected. */
                if (!qos || (qos & IEEE80211_QOS_ACKPOLICY) !=
                    IEEE80211_QOS_ACKPOLICY_NOACK)
                        flags |= WPI_TX_NEED_ACK;
        }

        if (!IEEE80211_QOS_HAS_SEQ(wh))
                flags |= WPI_TX_AUTO_SEQ;
        if (wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG)
                flags |= WPI_TX_MORE_FRAG;

        /* Check if frame must be protected using RTS/CTS or CTS-to-self. */
        if (!ismcast) {
                /* NB: Group frames are sent using CCK in 802.11b/g. */
                if (totlen + IEEE80211_CRC_LEN > vap->iv_rtsthreshold) {
                        flags |= WPI_TX_NEED_RTS;
                } else if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
                    WPI_RATE_IS_OFDM(rate)) {
                        if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
                                flags |= WPI_TX_NEED_CTS;
                        else if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
                                flags |= WPI_TX_NEED_RTS;
                }

                if (flags & (WPI_TX_NEED_RTS | WPI_TX_NEED_CTS))
                        flags |= WPI_TX_FULL_TXOP;
        }

        memset(tx, 0, sizeof (struct wpi_cmd_data));
        if (type == IEEE80211_FC0_TYPE_MGT) {
                uint8_t subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;

                /* Tell HW to set timestamp in probe responses. */
                if (subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
                        flags |= WPI_TX_INSERT_TSTAMP;
                if (subtype == IEEE80211_FC0_SUBTYPE_ASSOC_REQ ||
                    subtype == IEEE80211_FC0_SUBTYPE_REASSOC_REQ)
                        tx->timeout = htole16(3);
                else
                        tx->timeout = htole16(2);
        }

        if (ismcast || type != IEEE80211_FC0_TYPE_DATA)
                tx->id = WPI_ID_BROADCAST;
        else {
                if (wn->id == WPI_ID_UNDEFINED) {
                        device_printf(sc->sc_dev,
                            "%s: undefined node id\n", __func__);
                        return (EINVAL);
                }

                tx->id = wn->id;
        }

        if (!swcrypt) {
                switch (k->wk_cipher->ic_cipher) {
                case IEEE80211_CIPHER_AES_CCM:
                        tx->security = WPI_CIPHER_CCMP;
                        break;

                default:
                        break;
                }

                memcpy(tx->key, ieee80211_crypto_get_key_data(k),
                    ieee80211_crypto_get_key_len(k));
        }

        if (wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG) {
                struct mbuf *next = m->m_nextpkt;

                tx->lnext = htole16(next->m_pkthdr.len);
                tx->fnext = htole32(tx->security |
                                    (flags & WPI_TX_NEED_ACK) |
                                    WPI_NEXT_STA_ID(tx->id));
        }

        tx->len = htole16(totlen);
        tx->flags = htole32(flags);
        tx->plcp = rate2plcp(rate);
        tx->tid = tid;
        tx->lifetime = htole32(WPI_LIFETIME_INFINITE);
        tx->ofdm_mask = 0xff;
        tx->cck_mask = 0x0f;
        tx->rts_ntries = 7;
        tx->data_ntries = tp->maxretry;

        tx_data.ni = ni;
        tx_data.m = m;
        tx_data.size = sizeof(struct wpi_cmd_data);
        tx_data.code = WPI_CMD_TX_DATA;
        tx_data.ac = ac;

        return wpi_cmd2(sc, &tx_data);
}

static int
wpi_tx_data_raw(struct wpi_softc *sc, struct mbuf *m,
    struct ieee80211_node *ni, const struct ieee80211_bpf_params *params)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct ieee80211_key *k = NULL;
        struct ieee80211_frame *wh;
        struct wpi_buf tx_data;
        struct wpi_cmd_data *tx = (struct wpi_cmd_data *)&tx_data.data;
        uint32_t flags;
        uint8_t ac, type, rate;
        int swcrypt, totlen;

        wh = mtod(m, struct ieee80211_frame *);
        type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
        swcrypt = 1;

        ac = params->ibp_pri & 3;

        /* Choose a TX rate index. */
        rate = params->ibp_rate0;

        flags = 0;
        if (!IEEE80211_QOS_HAS_SEQ(wh))
                flags |= WPI_TX_AUTO_SEQ;
        if ((params->ibp_flags & IEEE80211_BPF_NOACK) == 0)
                flags |= WPI_TX_NEED_ACK;
        if (params->ibp_flags & IEEE80211_BPF_RTS)
                flags |= WPI_TX_NEED_RTS;
        if (params->ibp_flags & IEEE80211_BPF_CTS)
                flags |= WPI_TX_NEED_CTS;
        if (flags & (WPI_TX_NEED_RTS | WPI_TX_NEED_CTS))
                flags |= WPI_TX_FULL_TXOP;

        /* Encrypt the frame if need be. */
        if (params->ibp_flags & IEEE80211_BPF_CRYPTO) {
                /* Retrieve key for TX. */
                k = ieee80211_crypto_encap(ni, m);
                if (k == NULL)
                        return (ENOBUFS);

                swcrypt = k->wk_flags & IEEE80211_KEY_SWCRYPT;

                /* 802.11 header may have moved. */
                wh = mtod(m, struct ieee80211_frame *);
        }
        totlen = m->m_pkthdr.len;

        if (ieee80211_radiotap_active_vap(vap)) {
                struct wpi_tx_radiotap_header *tap = &sc->sc_txtap;

                tap->wt_flags = 0;
                tap->wt_rate = rate;
                if (params->ibp_flags & IEEE80211_BPF_CRYPTO)
                        tap->wt_flags |= IEEE80211_RADIOTAP_F_WEP;

                ieee80211_radiotap_tx(vap, m);
        }

        memset(tx, 0, sizeof (struct wpi_cmd_data));
        if (type == IEEE80211_FC0_TYPE_MGT) {
                uint8_t subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;

                /* Tell HW to set timestamp in probe responses. */
                if (subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
                        flags |= WPI_TX_INSERT_TSTAMP;
                if (subtype == IEEE80211_FC0_SUBTYPE_ASSOC_REQ ||
                    subtype == IEEE80211_FC0_SUBTYPE_REASSOC_REQ)
                        tx->timeout = htole16(3);
                else
                        tx->timeout = htole16(2);
        }

        if (!swcrypt) {
                switch (k->wk_cipher->ic_cipher) {
                case IEEE80211_CIPHER_AES_CCM:
                        tx->security = WPI_CIPHER_CCMP;
                        break;

                default:
                        break;
                }

                memcpy(tx->key, ieee80211_crypto_get_key_data(k),
                    ieee80211_crypto_get_key_len(k));
        }

        tx->len = htole16(totlen);
        tx->flags = htole32(flags);
        tx->plcp = rate2plcp(rate);
        tx->id = WPI_ID_BROADCAST;
        tx->lifetime = htole32(WPI_LIFETIME_INFINITE);
        tx->rts_ntries = params->ibp_try1;
        tx->data_ntries = params->ibp_try0;

        tx_data.ni = ni;
        tx_data.m = m;
        tx_data.size = sizeof(struct wpi_cmd_data);
        tx_data.code = WPI_CMD_TX_DATA;
        tx_data.ac = ac;

        return wpi_cmd2(sc, &tx_data);
}

static __inline int
wpi_tx_ring_free_space(struct wpi_softc *sc, uint16_t ac)
{
        struct wpi_tx_ring *ring = &sc->txq[ac];
        int retval;

        WPI_TXQ_STATE_LOCK(sc);
        retval = WPI_TX_RING_HIMARK - ring->queued;
        WPI_TXQ_STATE_UNLOCK(sc);

        return retval;
}

static int
wpi_raw_xmit(struct ieee80211_node *ni, struct mbuf *m,
    const struct ieee80211_bpf_params *params)
{
        struct ieee80211com *ic = ni->ni_ic;
        struct wpi_softc *sc = ic->ic_softc;
        uint16_t ac;
        int error = 0;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        ac = M_WME_GETAC(m);

        WPI_TX_LOCK(sc);

        /* NB: no fragments here */
        if (sc->sc_running == 0 || wpi_tx_ring_free_space(sc, ac) < 1) {
                error = sc->sc_running ? ENOBUFS : ENETDOWN;
                goto unlock;
        }

        if (params == NULL) {
                /*
                 * Legacy path; interpret frame contents to decide
                 * precisely how to send the frame.
                 */
                error = wpi_tx_data(sc, m, ni);
        } else {
                /*
                 * Caller supplied explicit parameters to use in
                 * sending the frame.
                 */
                error = wpi_tx_data_raw(sc, m, ni, params);
        }

unlock: WPI_TX_UNLOCK(sc);

        if (error != 0) {
                m_freem(m);
                DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);

                return error;
        }

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;
}

static int
wpi_transmit(struct ieee80211com *ic, struct mbuf *m)
{
        struct wpi_softc *sc = ic->ic_softc;
        struct ieee80211_node *ni;
        struct mbuf *mnext;
        uint16_t ac;
        int error, nmbufs;

        WPI_TX_LOCK(sc);
        DPRINTF(sc, WPI_DEBUG_XMIT, "%s: called\n", __func__);

        /* Check if interface is up & running. */
        if (__predict_false(sc->sc_running == 0)) {
                error = ENXIO;
                goto unlock;
        }

        nmbufs = 1;
        for (mnext = m->m_nextpkt; mnext != NULL; mnext = mnext->m_nextpkt)
                nmbufs++;

        /* Check for available space. */
        ac = M_WME_GETAC(m);
        if (wpi_tx_ring_free_space(sc, ac) < nmbufs) {
                error = ENOBUFS;
                goto unlock;
        }

        error = 0;
        ni = (struct ieee80211_node *)m->m_pkthdr.rcvif;
        do {
                mnext = m->m_nextpkt;
                if (wpi_tx_data(sc, m, ni) != 0) {
                        if_inc_counter(ni->ni_vap->iv_ifp, IFCOUNTER_OERRORS,
                            nmbufs);
                        wpi_free_txfrags(sc, ac);
                        ieee80211_free_mbuf(m);
                        ieee80211_free_node(ni);
                        break;
                }
        } while((m = mnext) != NULL);

        DPRINTF(sc, WPI_DEBUG_XMIT, "%s: done\n", __func__);

unlock: WPI_TX_UNLOCK(sc);

        return (error);
}

static void
wpi_watchdog_rfkill(void *arg)
{
        struct wpi_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;

        DPRINTF(sc, WPI_DEBUG_WATCHDOG, "RFkill Watchdog: tick\n");

        /* No need to lock firmware memory. */
        if ((wpi_prph_read(sc, WPI_APMG_RFKILL) & 0x1) == 0) {
                /* Radio kill switch is still off. */
                callout_reset(&sc->watchdog_rfkill, hz, wpi_watchdog_rfkill,
                    sc);
        } else
                ieee80211_runtask(ic, &sc->sc_radioon_task);
}

static void
wpi_scan_timeout(void *arg)
{
        struct wpi_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;

        ic_printf(ic, "scan timeout\n");
        ieee80211_restart_all(ic);
}

static void
wpi_tx_timeout(void *arg)
{
        struct wpi_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;

        ic_printf(ic, "device timeout\n");
        ieee80211_restart_all(ic);
}

static void
wpi_parent(struct ieee80211com *ic)
{
        struct wpi_softc *sc = ic->ic_softc;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);

        if (ic->ic_nrunning > 0) {
                if (wpi_init(sc) == 0) {
                        ieee80211_notify_radio(ic, 1);
                        ieee80211_start_all(ic);
                } else {
                        ieee80211_notify_radio(ic, 0);
                        ieee80211_stop(vap);
                }
        } else {
                ieee80211_notify_radio(ic, 0);
                wpi_stop(sc);
        }
}

/*
 * Send a command to the firmware.
 */
static int
wpi_cmd(struct wpi_softc *sc, uint8_t code, const void *buf, uint16_t size,
    int async)
{
        struct wpi_tx_ring *ring = &sc->txq[WPI_CMD_QUEUE_NUM];
        struct wpi_tx_desc *desc;
        struct wpi_tx_data *data;
        struct wpi_tx_cmd *cmd;
        struct mbuf *m;
        bus_addr_t paddr;
        uint16_t totlen;
        int error;

        WPI_TXQ_LOCK(sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        if (__predict_false(sc->sc_running == 0)) {
                /* wpi_stop() was called */
                if (code == WPI_CMD_SCAN)
                        error = ENETDOWN;
                else
                        error = 0;

                goto fail;
        }

        if (async == 0)
                WPI_LOCK_ASSERT(sc);

        DPRINTF(sc, WPI_DEBUG_CMD, "%s: cmd %s size %u async %d\n",
            __func__, wpi_cmd_str(code), size, async);

        desc = &ring->desc[ring->cur];
        data = &ring->data[ring->cur];
        totlen = 4 + size;

        if (size > sizeof cmd->data) {
                /* Command is too large to fit in a descriptor. */
                if (totlen > MCLBYTES) {
                        error = EINVAL;
                        goto fail;
                }
                m = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUMPAGESIZE);
                if (m == NULL) {
                        error = ENOMEM;
                        goto fail;
                }
                cmd = mtod(m, struct wpi_tx_cmd *);
                error = bus_dmamap_load(ring->data_dmat, data->map, cmd,
                    totlen, wpi_dma_map_addr, &paddr, BUS_DMA_NOWAIT);
                if (error != 0) {
                        m_freem(m);
                        goto fail;
                }
                data->m = m;
        } else {
                cmd = &ring->cmd[ring->cur];
                paddr = data->cmd_paddr;
        }

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

        desc->nsegs = 1 + (WPI_PAD32(size) << 4);
        desc->segs[0].addr = htole32(paddr);
        desc->segs[0].len  = htole32(totlen);

        if (size > sizeof cmd->data) {
                bus_dmamap_sync(ring->data_dmat, data->map,
                    BUS_DMASYNC_PREWRITE);
        } else {
                bus_dmamap_sync(ring->data_dmat, ring->cmd_dma.map,
                    BUS_DMASYNC_PREWRITE);
        }
        bus_dmamap_sync(ring->desc_dma.tag, ring->desc_dma.map,
            BUS_DMASYNC_PREWRITE);

        /* Kick command ring. */
        ring->cur = (ring->cur + 1) % WPI_TX_RING_COUNT;
        sc->sc_update_tx_ring(sc, ring);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        WPI_TXQ_UNLOCK(sc);

        return async ? 0 : mtx_sleep(cmd, &sc->sc_mtx, PCATCH, "wpicmd", hz);

fail:   DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);

        WPI_TXQ_UNLOCK(sc);

        return error;
}

/*
 * Configure HW multi-rate retries.
 */
static int
wpi_mrr_setup(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_mrr_setup mrr;
        uint8_t i;
        int error;

        /* CCK rates (not used with 802.11a). */
        for (i = WPI_RIDX_CCK1; i <= WPI_RIDX_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_RIDX_CCK1) ? WPI_RIDX_CCK1 : i - 1;
                /* Try twice at this rate before falling back to "next". */
                mrr.rates[i].ntries = WPI_NTRIES_DEFAULT;
        }
        /* OFDM rates (not used with 802.11b). */
        for (i = WPI_RIDX_OFDM6; i <= WPI_RIDX_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_RIDX_OFDM6) ?
                    ((ic->ic_curmode == IEEE80211_MODE_11A) ?
                        WPI_RIDX_OFDM6 : WPI_RIDX_CCK2) :
                    i - 1;
                /* Try twice at this rate before falling back to "next". */
                mrr.rates[i].ntries = WPI_NTRIES_DEFAULT;
        }
        /* 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) {
                device_printf(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) {
                device_printf(sc->sc_dev,
                    "could not setup MRR for data frames\n");
                return error;
        }
        return 0;
}

static int
wpi_add_node(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct ieee80211com *ic = ni->ni_ic;
        struct wpi_vap *wvp = WPI_VAP(ni->ni_vap);
        struct wpi_node *wn = WPI_NODE(ni);
        struct wpi_node_info node;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (wn->id == WPI_ID_UNDEFINED)
                return EINVAL;

        memset(&node, 0, sizeof node);
        IEEE80211_ADDR_COPY(node.macaddr, ni->ni_macaddr);
        node.id = wn->id;
        node.plcp = (ic->ic_curmode == IEEE80211_MODE_11A) ?
            wpi_ridx_to_plcp[WPI_RIDX_OFDM6] : wpi_ridx_to_plcp[WPI_RIDX_CCK1];
        node.action = htole32(WPI_ACTION_SET_RATE);
        node.antenna = WPI_ANTENNA_BOTH;

        DPRINTF(sc, WPI_DEBUG_NODE, "%s: adding node %d (%s)\n", __func__,
            wn->id, ether_sprintf(ni->ni_macaddr));

        error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: wpi_cmd() call failed with error code %d\n", __func__,
                    error);
                return error;
        }

        if (wvp->wv_gtk != 0) {
                error = wpi_set_global_keys(ni);
                if (error != 0) {
                        device_printf(sc->sc_dev,
                            "%s: error while setting global keys\n", __func__);
                        return ENXIO;
                }
        }

        return 0;
}

/*
 * Broadcast node is used to send group-addressed and management frames.
 */
static int
wpi_add_broadcast_node(struct wpi_softc *sc, int async)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct wpi_node_info node;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        memset(&node, 0, sizeof node);
        IEEE80211_ADDR_COPY(node.macaddr, ieee80211broadcastaddr);
        node.id = WPI_ID_BROADCAST;
        node.plcp = (ic->ic_curmode == IEEE80211_MODE_11A) ?
            wpi_ridx_to_plcp[WPI_RIDX_OFDM6] : wpi_ridx_to_plcp[WPI_RIDX_CCK1];
        node.action = htole32(WPI_ACTION_SET_RATE);
        node.antenna = WPI_ANTENNA_BOTH;

        DPRINTF(sc, WPI_DEBUG_NODE, "%s: adding broadcast node\n", __func__);

        return wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, async);
}

static int
wpi_add_sta_node(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct wpi_node *wn = WPI_NODE(ni);
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        wn->id = wpi_add_node_entry_sta(sc);

        if ((error = wpi_add_node(sc, ni)) != 0) {
                wpi_del_node_entry(sc, wn->id);
                wn->id = WPI_ID_UNDEFINED;
                return error;
        }

        return 0;
}

static int
wpi_add_ibss_node(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct wpi_node *wn = WPI_NODE(ni);
        int error;

        KASSERT(wn->id == WPI_ID_UNDEFINED,
            ("the node %d was added before", wn->id));

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if ((wn->id = wpi_add_node_entry_adhoc(sc)) == WPI_ID_UNDEFINED) {
                device_printf(sc->sc_dev, "%s: h/w table is full\n", __func__);
                return ENOMEM;
        }

        if ((error = wpi_add_node(sc, ni)) != 0) {
                wpi_del_node_entry(sc, wn->id);
                wn->id = WPI_ID_UNDEFINED;
                return error;
        }

        return 0;
}

static void
wpi_del_node(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct wpi_node *wn = WPI_NODE(ni);
        struct wpi_cmd_del_node node;
        int error;

        KASSERT(wn->id != WPI_ID_UNDEFINED, ("undefined node id passed"));

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        memset(&node, 0, sizeof node);
        IEEE80211_ADDR_COPY(node.macaddr, ni->ni_macaddr);
        node.count = 1;

        DPRINTF(sc, WPI_DEBUG_NODE, "%s: deleting node %d (%s)\n", __func__,
            wn->id, ether_sprintf(ni->ni_macaddr));

        error = wpi_cmd(sc, WPI_CMD_DEL_NODE, &node, sizeof node, 1);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not delete node %u, error %d\n", __func__,
                    wn->id, error);
        }
}

static int
wpi_updateedca(struct ieee80211com *ic)
{
#define WPI_EXP2(x)     ((1 << (x)) - 1)        /* CWmin = 2^ECWmin - 1 */
        struct wpi_softc *sc = ic->ic_softc;
        struct chanAccParams chp;
        struct wpi_edca_params cmd;
        int aci, error;

        ieee80211_wme_ic_getparams(ic, &chp);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        memset(&cmd, 0, sizeof cmd);
        cmd.flags = htole32(WPI_EDCA_UPDATE);
        for (aci = 0; aci < WME_NUM_AC; aci++) {
                const struct wmeParams *ac = &chp.cap_wmeParams[aci];
                cmd.ac[aci].aifsn = ac->wmep_aifsn;
                cmd.ac[aci].cwmin = htole16(WPI_EXP2(ac->wmep_logcwmin));
                cmd.ac[aci].cwmax = htole16(WPI_EXP2(ac->wmep_logcwmax));
                cmd.ac[aci].txoplimit = 
                    htole16(IEEE80211_TXOP_TO_US(ac->wmep_txopLimit));

                DPRINTF(sc, WPI_DEBUG_EDCA,
                    "setting WME for queue %d aifsn=%d cwmin=%d cwmax=%d "
                    "txoplimit=%d\n", aci, cmd.ac[aci].aifsn,
                    cmd.ac[aci].cwmin, cmd.ac[aci].cwmax,
                    cmd.ac[aci].txoplimit);
        }
        error = wpi_cmd(sc, WPI_CMD_EDCA_PARAMS, &cmd, sizeof cmd, 1);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return error;
#undef WPI_EXP2
}

static void
wpi_set_promisc(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);
        uint32_t promisc_filter;

        promisc_filter = WPI_FILTER_CTL;
        if (vap != NULL && vap->iv_opmode != IEEE80211_M_HOSTAP)
                promisc_filter |= WPI_FILTER_PROMISC;

        if (ic->ic_promisc > 0)
                sc->rxon.filter |= htole32(promisc_filter);
        else
                sc->rxon.filter &= ~htole32(promisc_filter);
}

static void
wpi_update_promisc(struct ieee80211com *ic)
{
        struct wpi_softc *sc = ic->ic_softc;

        WPI_LOCK(sc);
        if (sc->sc_running == 0) {
                WPI_UNLOCK(sc);
                return;
        }
        WPI_UNLOCK(sc);

        WPI_RXON_LOCK(sc);
        wpi_set_promisc(sc);

        if (wpi_send_rxon(sc, 1, 1) != 0) {
                device_printf(sc->sc_dev, "%s: could not send RXON\n",
                    __func__);
        }
        WPI_RXON_UNLOCK(sc);
}

static void
wpi_update_mcast(struct ieee80211com *ic)
{
        /* Ignore */
}

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

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        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 int
wpi_set_timing(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct wpi_cmd_timing cmd;
        uint64_t val, mod;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

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

        /* Compute remaining time until next beacon. */
        val = (uint64_t)ni->ni_intval * IEEE80211_DUR_TU;
        mod = le64toh(cmd.tstamp) % val;
        cmd.binitval = htole32((uint32_t)(val - mod));

        DPRINTF(sc, WPI_DEBUG_RESET, "timing bintval=%u tstamp=%ju, init=%u\n",
            ni->ni_intval, le64toh(cmd.tstamp), (uint32_t)(val - mod));

        return wpi_cmd(sc, WPI_CMD_TIMING, &cmd, sizeof cmd, 1);
}

/*
 * This function is called periodically (every 60 seconds) to adjust output
 * power to temperature changes.
 */
static void
wpi_power_calibration(struct wpi_softc *sc)
{
        int temp;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        /* Update sensor data. */
        temp = (int)WPI_READ(sc, WPI_UCODE_GP2);
        DPRINTF(sc, WPI_DEBUG_TEMP, "Temp in calibration is: %d\n", temp);

        /* Sanity-check read value. */
        if (temp < -260 || temp > 25) {
                /* This can't be correct, ignore. */
                DPRINTF(sc, WPI_DEBUG_TEMP,
                    "out-of-range temperature reported: %d\n", temp);
                return;
        }

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

/*
 * Set TX power for current channel.
 */
static int
wpi_set_txpower(struct wpi_softc *sc, int async)
{
        struct wpi_power_group *group;
        struct wpi_cmd_txpower cmd;
        uint8_t chan;
        int idx, is_chan_5ghz, i;

        /* Retrieve current channel from last RXON. */
        chan = sc->rxon.chan;
        is_chan_5ghz = (sc->rxon.flags & htole32(WPI_RXON_24GHZ)) == 0;

        /* Find the TX power group to which this channel belongs. */
        if (is_chan_5ghz) {
                for (group = &sc->groups[1]; group < &sc->groups[4]; group++)
                        if (chan <= group->chan)
                                break;
        } else
                group = &sc->groups[0];

        memset(&cmd, 0, sizeof cmd);
        cmd.band = is_chan_5ghz ? WPI_BAND_5GHZ : WPI_BAND_2GHZ;
        cmd.chan = htole16(chan);

        /* Set TX power for all OFDM and CCK rates. */
        for (i = 0; i <= WPI_RIDX_MAX ; i++) {
                /* Retrieve TX power for this channel/rate. */
                idx = wpi_get_power_index(sc, group, chan, is_chan_5ghz, i);

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

                if (is_chan_5ghz) {
                        cmd.rates[i].rf_gain = wpi_rf_gain_5ghz[idx];
                        cmd.rates[i].dsp_gain = wpi_dsp_gain_5ghz[idx];
                } else {
                        cmd.rates[i].rf_gain = wpi_rf_gain_2ghz[idx];
                        cmd.rates[i].dsp_gain = wpi_dsp_gain_2ghz[idx];
                }
                DPRINTF(sc, WPI_DEBUG_TEMP,
                    "chan %d/ridx %d: power index %d\n", chan, i, idx);
        }

        return wpi_cmd(sc, WPI_CMD_TXPOWER, &cmd, sizeof cmd, 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,
    uint8_t chan, int is_chan_5ghz, int ridx)
{
/* 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 wpi_power_sample *sample;
        int pwr, idx;

        /* Default TX power is group maximum TX power minus 3dB. */
        pwr = group->maxpwr / 2;

        /* Decrease TX power for highest OFDM rates to reduce distortion. */
        switch (ridx) {
        case WPI_RIDX_OFDM36:
                pwr -= is_chan_5ghz ?  5 : 0;
                break;
        case WPI_RIDX_OFDM48:
                pwr -= is_chan_5ghz ? 10 : 7;
                break;
        case WPI_RIDX_OFDM54:
                pwr -= is_chan_5ghz ? 12 : 9;
                break;
        }

        /* Never exceed the channel maximum allowed TX power. */
        pwr = min(pwr, sc->maxpwr[chan]);

        /* Retrieve TX 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 TX power for CCK rates (-5dB). */
        if (ridx >= WPI_RIDX_CCK1)
                idx += 10;

        /* Make sure idx stays 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
}

/*
 * Set STA mode power saving level (between 0 and 5).
 * Level 0 is CAM (Continuously Aware Mode), 5 is for maximum power saving.
 */
static int
wpi_set_pslevel(struct wpi_softc *sc, uint8_t dtim, int level, int async)
{
        struct wpi_pmgt_cmd cmd;
        const struct wpi_pmgt *pmgt;
        uint32_t max, reg;
        uint8_t skip_dtim;
        int i;

        DPRINTF(sc, WPI_DEBUG_PWRSAVE,
            "%s: dtim=%d, level=%d, async=%d\n",
            __func__, dtim, level, async);

        /* Select which PS parameters to use. */
        if (dtim <= 10)
                pmgt = &wpi_pmgt[0][level];
        else
                pmgt = &wpi_pmgt[1][level];

        memset(&cmd, 0, sizeof cmd);
        if (level != 0) /* not CAM */
                cmd.flags |= htole16(WPI_PS_ALLOW_SLEEP);
        /* Retrieve PCIe Active State Power Management (ASPM). */
        reg = pci_read_config(sc->sc_dev, sc->sc_cap_off + PCIER_LINK_CTL, 1);
        if (!(reg & PCIEM_LINK_CTL_ASPMC_L0S))  /* L0s Entry disabled. */
                cmd.flags |= htole16(WPI_PS_PCI_PMGT);

        cmd.rxtimeout = htole32(pmgt->rxtimeout * IEEE80211_DUR_TU);
        cmd.txtimeout = htole32(pmgt->txtimeout * IEEE80211_DUR_TU);

        if (dtim == 0) {
                dtim = 1;
                skip_dtim = 0;
        } else
                skip_dtim = pmgt->skip_dtim;

        if (skip_dtim != 0) {
                cmd.flags |= htole16(WPI_PS_SLEEP_OVER_DTIM);
                max = pmgt->intval[4];
                if (max == (uint32_t)-1)
                        max = dtim * (skip_dtim + 1);
                else if (max > dtim)
                        max = rounddown(max, dtim);
        } else
                max = dtim;

        for (i = 0; i < 5; i++)
                cmd.intval[i] = htole32(MIN(max, pmgt->intval[i]));

        return wpi_cmd(sc, WPI_CMD_SET_POWER_MODE, &cmd, sizeof cmd, async);
}

static int
wpi_send_btcoex(struct wpi_softc *sc)
{
        struct wpi_bluetooth cmd;

        memset(&cmd, 0, sizeof cmd);
        cmd.flags = WPI_BT_COEX_MODE_4WIRE;
        cmd.lead_time = WPI_BT_LEAD_TIME_DEF;
        cmd.max_kill = WPI_BT_MAX_KILL_DEF;
        DPRINTF(sc, WPI_DEBUG_RESET, "%s: configuring bluetooth coexistence\n",
            __func__);
        return wpi_cmd(sc, WPI_CMD_BT_COEX, &cmd, sizeof(cmd), 0);
}

static int
wpi_send_rxon(struct wpi_softc *sc, int assoc, int async)
{
        int error;

        if (async)
                WPI_RXON_LOCK_ASSERT(sc);

        if (assoc && wpi_check_bss_filter(sc) != 0) {
                struct wpi_assoc rxon_assoc;

                rxon_assoc.flags = sc->rxon.flags;
                rxon_assoc.filter = sc->rxon.filter;
                rxon_assoc.ofdm_mask = sc->rxon.ofdm_mask;
                rxon_assoc.cck_mask = sc->rxon.cck_mask;
                rxon_assoc.reserved = 0;

                error = wpi_cmd(sc, WPI_CMD_RXON_ASSOC, &rxon_assoc,
                    sizeof (struct wpi_assoc), async);
                if (error != 0) {
                        device_printf(sc->sc_dev,
                            "RXON_ASSOC command failed, error %d\n", error);
                        return error;
                }
        } else {
                if (async) {
                        WPI_NT_LOCK(sc);
                        error = wpi_cmd(sc, WPI_CMD_RXON, &sc->rxon,
                            sizeof (struct wpi_rxon), async);
                        if (error == 0)
                                wpi_clear_node_table(sc);
                        WPI_NT_UNLOCK(sc);
                } else {
                        error = wpi_cmd(sc, WPI_CMD_RXON, &sc->rxon,
                            sizeof (struct wpi_rxon), async);
                        if (error == 0)
                                wpi_clear_node_table(sc);
                }

                if (error != 0) {
                        device_printf(sc->sc_dev,
                            "RXON command failed, error %d\n", error);
                        return error;
                }

                /* Add broadcast node. */
                error = wpi_add_broadcast_node(sc, async);
                if (error != 0) {
                        device_printf(sc->sc_dev,
                            "could not add broadcast node, error %d\n", error);
                        return error;
                }
        }

        /* Configuration has changed, set Tx power accordingly. */
        if ((error = wpi_set_txpower(sc, async)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not set TX power, error %d\n", __func__, error);
                return error;
        }

        return 0;
}

/**
 * Configure the card to listen to a particular channel, this transisions the
 * card in to being able to receive frames from remote devices.
 */
static int
wpi_config(struct wpi_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);
        struct ieee80211_channel *c = ic->ic_curchan;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /* Set power saving level to CAM during initialization. */
        if ((error = wpi_set_pslevel(sc, 0, 0, 0)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not set power saving level\n", __func__);
                return error;
        }

        /* Configure bluetooth coexistence. */
        if ((error = wpi_send_btcoex(sc)) != 0) {
                device_printf(sc->sc_dev,
                    "could not configure bluetooth coexistence\n");
                return error;
        }

        /* Configure adapter. */
        memset(&sc->rxon, 0, sizeof (struct wpi_rxon));
        IEEE80211_ADDR_COPY(sc->rxon.myaddr, vap->iv_myaddr);

        /* Set default channel. */
        sc->rxon.chan = ieee80211_chan2ieee(ic, c);
        sc->rxon.flags = htole32(WPI_RXON_TSF | WPI_RXON_CTS_TO_SELF);
        if (IEEE80211_IS_CHAN_2GHZ(c))
                sc->rxon.flags |= htole32(WPI_RXON_AUTO | WPI_RXON_24GHZ);

        sc->rxon.filter = WPI_FILTER_MULTICAST;
        switch (ic->ic_opmode) {
        case IEEE80211_M_STA:
                sc->rxon.mode = WPI_MODE_STA;
                break;
        case IEEE80211_M_IBSS:
                sc->rxon.mode = WPI_MODE_IBSS;
                sc->rxon.filter |= WPI_FILTER_BEACON;
                break;
        case IEEE80211_M_HOSTAP:
                /* XXX workaround for beaconing */
                sc->rxon.mode = WPI_MODE_IBSS;
                sc->rxon.filter |= WPI_FILTER_ASSOC | WPI_FILTER_PROMISC;
                break;
        case IEEE80211_M_AHDEMO:
                sc->rxon.mode = WPI_MODE_HOSTAP;
                break;
        case IEEE80211_M_MONITOR:
                sc->rxon.mode = WPI_MODE_MONITOR;
                break;
        default:
                device_printf(sc->sc_dev, "unknown opmode %d\n",
                    ic->ic_opmode);
                return EINVAL;
        }
        sc->rxon.filter = htole32(sc->rxon.filter);
        wpi_set_promisc(sc);
        sc->rxon.cck_mask  = 0x0f;      /* not yet negotiated */
        sc->rxon.ofdm_mask = 0xff;      /* not yet negotiated */

        if ((error = wpi_send_rxon(sc, 0, 0)) != 0) {
                device_printf(sc->sc_dev, "%s: could not send RXON\n",
                    __func__);
                return error;
        }

        /* Setup rate scalling. */
        if ((error = wpi_mrr_setup(sc)) != 0) {
                device_printf(sc->sc_dev, "could not setup MRR, error %d\n",
                    error);
                return error;
        }

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;
}

static uint16_t
wpi_get_active_dwell_time(struct wpi_softc *sc,
    struct ieee80211_channel *c, uint8_t n_probes)
{
        /* No channel? Default to 2GHz settings. */
        if (c == NULL || IEEE80211_IS_CHAN_2GHZ(c)) {
                return (WPI_ACTIVE_DWELL_TIME_2GHZ +
                WPI_ACTIVE_DWELL_FACTOR_2GHZ * (n_probes + 1));
        }

        /* 5GHz dwell time. */
        return (WPI_ACTIVE_DWELL_TIME_5GHZ +
            WPI_ACTIVE_DWELL_FACTOR_5GHZ * (n_probes + 1));
}

/*
 * Limit the total dwell time.
 *
 * Returns the dwell time in milliseconds.
 */
static uint16_t
wpi_limit_dwell(struct wpi_softc *sc, uint16_t dwell_time)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);
        uint16_t bintval = 0;

        /* bintval is in TU (1.024mS) */
        if (vap != NULL)
                bintval = vap->iv_bss->ni_intval;

        /*
         * If it's non-zero, we should calculate the minimum of
         * it and the DWELL_BASE.
         *
         * XXX Yes, the math should take into account that bintval
         * is 1.024mS, not 1mS..
         */
        if (bintval > 0) {
                DPRINTF(sc, WPI_DEBUG_SCAN, "%s: bintval=%d\n", __func__,
                    bintval);
                return (MIN(dwell_time, bintval - WPI_CHANNEL_TUNE_TIME * 2));
        }

        /* No association context? Default. */
        return dwell_time;
}

static uint16_t
wpi_get_passive_dwell_time(struct wpi_softc *sc, struct ieee80211_channel *c)
{
        uint16_t passive;

        if (c == NULL || IEEE80211_IS_CHAN_2GHZ(c))
                passive = WPI_PASSIVE_DWELL_BASE + WPI_PASSIVE_DWELL_TIME_2GHZ;
        else
                passive = WPI_PASSIVE_DWELL_BASE + WPI_PASSIVE_DWELL_TIME_5GHZ;

        /* Clamp to the beacon interval if we're associated. */
        return (wpi_limit_dwell(sc, passive));
}

static uint32_t
wpi_get_scan_pause_time(uint32_t time, uint16_t bintval)
{
        uint32_t mod = (time % bintval) * IEEE80211_DUR_TU;
        uint32_t nbeacons = time / bintval;

        if (mod > WPI_PAUSE_MAX_TIME)
                mod = WPI_PAUSE_MAX_TIME;

        return WPI_PAUSE_SCAN(nbeacons, mod);
}

/*
 * Send a scan request to the firmware.
 */
static int
wpi_scan(struct wpi_softc *sc, struct ieee80211_channel *c)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211_scan_state *ss = ic->ic_scan;
        struct ieee80211vap *vap = ss->ss_vap;
        struct wpi_scan_hdr *hdr;
        struct wpi_cmd_data *tx;
        struct wpi_scan_essid *essids;
        struct wpi_scan_chan *chan;
        struct ieee80211_frame *wh;
        struct ieee80211_rateset *rs;
        uint16_t bintval, buflen, dwell_active, dwell_passive;
        uint8_t *buf, *frm, i, nssid;
        int bgscan, error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /*
         * We are absolutely not allowed to send a scan command when another
         * scan command is pending.
         */
        if (callout_pending(&sc->scan_timeout)) {
                device_printf(sc->sc_dev, "%s: called whilst scanning!\n",
                    __func__);
                error = EAGAIN;
                goto fail;
        }

        bgscan = wpi_check_bss_filter(sc);
        bintval = vap->iv_bss->ni_intval;
        if (bgscan != 0 &&
            bintval < WPI_QUIET_TIME_DEFAULT + WPI_CHANNEL_TUNE_TIME * 2) {
                error = EOPNOTSUPP;
                goto fail;
        }

        buf = malloc(WPI_SCAN_MAXSZ, M_DEVBUF, M_NOWAIT | M_ZERO);
        if (buf == NULL) {
                device_printf(sc->sc_dev,
                    "%s: could not allocate buffer for scan command\n",
                    __func__);
                error = ENOMEM;
                goto fail;
        }
        hdr = (struct wpi_scan_hdr *)buf;

        /*
         * Move to the next channel if no packets are received within 10 msecs
         * after sending the probe request.
         */
        hdr->quiet_time = htole16(WPI_QUIET_TIME_DEFAULT);
        hdr->quiet_threshold = htole16(1);

        if (bgscan != 0) {
                /*
                 * Max needs to be greater than active and passive and quiet!
                 * It's also in microseconds!
                 */
                hdr->max_svc = htole32(250 * IEEE80211_DUR_TU);
                hdr->pause_svc = htole32(wpi_get_scan_pause_time(100,
                    bintval));
        }

        hdr->filter = htole32(WPI_FILTER_MULTICAST | WPI_FILTER_BEACON);

        tx = (struct wpi_cmd_data *)(hdr + 1);
        tx->flags = htole32(WPI_TX_AUTO_SEQ);
        tx->id = WPI_ID_BROADCAST;
        tx->lifetime = htole32(WPI_LIFETIME_INFINITE);

        if (IEEE80211_IS_CHAN_5GHZ(c)) {
                /* Send probe requests at 6Mbps. */
                tx->plcp = wpi_ridx_to_plcp[WPI_RIDX_OFDM6];
                rs = &ic->ic_sup_rates[IEEE80211_MODE_11A];
        } else {
                hdr->flags = htole32(WPI_RXON_24GHZ | WPI_RXON_AUTO);
                /* Send probe requests at 1Mbps. */
                tx->plcp = wpi_ridx_to_plcp[WPI_RIDX_CCK1];
                rs = &ic->ic_sup_rates[IEEE80211_MODE_11G];
        }

        essids = (struct wpi_scan_essid *)(tx + 1);
        nssid = MIN(ss->ss_nssid, WPI_SCAN_MAX_ESSIDS);
        for (i = 0; i < nssid; i++) {
                essids[i].id = IEEE80211_ELEMID_SSID;
                essids[i].len = MIN(ss->ss_ssid[i].len, IEEE80211_NWID_LEN);
                memcpy(essids[i].data, ss->ss_ssid[i].ssid, essids[i].len);
#ifdef WPI_DEBUG
                if (sc->sc_debug & WPI_DEBUG_SCAN) {
                        printf("Scanning Essid: ");
                        ieee80211_print_essid(essids[i].data, essids[i].len);
                        printf("\n");
                }
#endif
        }

        /*
         * Build a probe request frame.  Most of the following code is a
         * copy & paste of what is done in net80211.
         */
        wh = (struct ieee80211_frame *)(essids + WPI_SCAN_MAX_ESSIDS);
        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, ieee80211broadcastaddr);
        IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
        IEEE80211_ADDR_COPY(wh->i_addr3, ieee80211broadcastaddr);

        frm = (uint8_t *)(wh + 1);
        frm = ieee80211_add_ssid(frm, NULL, 0);
        frm = ieee80211_add_rates(frm, rs);
        if (rs->rs_nrates > IEEE80211_RATE_SIZE)
                frm = ieee80211_add_xrates(frm, rs);

        /* Set length of probe request. */
        tx->len = htole16(frm - (uint8_t *)wh);

        /*
         * Construct information about the channel that we
         * want to scan. The firmware expects this to be directly
         * after the scan probe request
         */
        chan = (struct wpi_scan_chan *)frm;
        chan->chan = ieee80211_chan2ieee(ic, c);
        chan->flags = 0;
        if (nssid) {
                hdr->crc_threshold = WPI_SCAN_CRC_TH_DEFAULT;
                chan->flags |= WPI_CHAN_NPBREQS(nssid);
        } else
                hdr->crc_threshold = WPI_SCAN_CRC_TH_NEVER;

        if (!IEEE80211_IS_CHAN_PASSIVE(c))
                chan->flags |= WPI_CHAN_ACTIVE;

        /*
         * Calculate the active/passive dwell times.
         */
        dwell_active = wpi_get_active_dwell_time(sc, c, nssid);
        dwell_passive = wpi_get_passive_dwell_time(sc, c);

        /* Make sure they're valid. */
        if (dwell_active > dwell_passive)
                dwell_active = dwell_passive;

        chan->active = htole16(dwell_active);
        chan->passive = htole16(dwell_passive);

        chan->dsp_gain = 0x6e;  /* Default level */

        if (IEEE80211_IS_CHAN_5GHZ(c))
                chan->rf_gain = 0x3b;
        else
                chan->rf_gain = 0x28;

        DPRINTF(sc, WPI_DEBUG_SCAN, "Scanning %u Passive: %d\n",
            chan->chan, IEEE80211_IS_CHAN_PASSIVE(c));

        hdr->nchan++;

        if (hdr->nchan == 1 && sc->rxon.chan == chan->chan) {
                /* XXX Force probe request transmission. */
                memcpy(chan + 1, chan, sizeof (struct wpi_scan_chan));

                chan++;

                /* Reduce unnecessary delay. */
                chan->flags = 0;
                chan->passive = chan->active = hdr->quiet_time;

                hdr->nchan++;
        }

        chan++;

        buflen = (uint8_t *)chan - buf;
        hdr->len = htole16(buflen);

        DPRINTF(sc, WPI_DEBUG_CMD, "sending scan command nchan=%d\n",
            hdr->nchan);
        error = wpi_cmd(sc, WPI_CMD_SCAN, buf, buflen, 1);
        free(buf, M_DEVBUF);

        if (error != 0)
                goto fail;

        callout_reset(&sc->scan_timeout, 5*hz, wpi_scan_timeout, sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;

fail:   DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);

        return error;
}

static int
wpi_auth(struct wpi_softc *sc, struct ieee80211vap *vap)
{
        struct ieee80211com *ic = vap->iv_ic;
        struct ieee80211_node *ni = vap->iv_bss;
        struct ieee80211_channel *c = ni->ni_chan;
        int error;

        WPI_RXON_LOCK(sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /* Update adapter configuration. */
        sc->rxon.associd = 0;
        sc->rxon.filter &= ~htole32(WPI_FILTER_BSS);
        IEEE80211_ADDR_COPY(sc->rxon.bssid, ni->ni_bssid);
        sc->rxon.chan = ieee80211_chan2ieee(ic, c);
        sc->rxon.flags = htole32(WPI_RXON_TSF | WPI_RXON_CTS_TO_SELF);
        if (IEEE80211_IS_CHAN_2GHZ(c))
                sc->rxon.flags |= htole32(WPI_RXON_AUTO | WPI_RXON_24GHZ);
        if (ic->ic_flags & IEEE80211_F_SHSLOT)
                sc->rxon.flags |= htole32(WPI_RXON_SHSLOT);
        if (ic->ic_flags & IEEE80211_F_SHPREAMBLE)
                sc->rxon.flags |= htole32(WPI_RXON_SHPREAMBLE);
        if (IEEE80211_IS_CHAN_A(c)) {
                sc->rxon.cck_mask  = 0;
                sc->rxon.ofdm_mask = 0x15;
        } else if (IEEE80211_IS_CHAN_B(c)) {
                sc->rxon.cck_mask  = 0x03;
                sc->rxon.ofdm_mask = 0;
        } else {
                /* Assume 802.11b/g. */
                sc->rxon.cck_mask  = 0x0f;
                sc->rxon.ofdm_mask = 0x15;
        }

        DPRINTF(sc, WPI_DEBUG_STATE, "rxon chan %d flags %x cck %x ofdm %x\n",
            sc->rxon.chan, sc->rxon.flags, sc->rxon.cck_mask,
            sc->rxon.ofdm_mask);

        if ((error = wpi_send_rxon(sc, 0, 1)) != 0) {
                device_printf(sc->sc_dev, "%s: could not send RXON\n",
                    __func__);
        }

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        WPI_RXON_UNLOCK(sc);

        return error;
}

static int
wpi_config_beacon(struct wpi_vap *wvp)
{
        struct ieee80211vap *vap = &wvp->wv_vap;
        struct ieee80211com *ic = vap->iv_ic;
        struct ieee80211_beacon_offsets *bo = &vap->iv_bcn_off;
        struct wpi_buf *bcn = &wvp->wv_bcbuf;
        struct wpi_softc *sc = ic->ic_softc;
        struct wpi_cmd_beacon *cmd = (struct wpi_cmd_beacon *)&bcn->data;
        struct ieee80211_tim_ie *tie;
        struct mbuf *m;
        uint8_t *ptr;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        WPI_VAP_LOCK_ASSERT(wvp);

        cmd->len = htole16(bcn->m->m_pkthdr.len);
        cmd->plcp = (ic->ic_curmode == IEEE80211_MODE_11A) ?
            wpi_ridx_to_plcp[WPI_RIDX_OFDM6] : wpi_ridx_to_plcp[WPI_RIDX_CCK1];

        /* XXX seems to be unused */
        if (*(bo->bo_tim) == IEEE80211_ELEMID_TIM) {
                tie = (struct ieee80211_tim_ie *) bo->bo_tim;
                ptr = mtod(bcn->m, uint8_t *);

                cmd->tim = htole16(bo->bo_tim - ptr);
                cmd->timsz = tie->tim_len;
        }

        /* Necessary for recursion in ieee80211_beacon_update(). */
        m = bcn->m;
        bcn->m = m_dup(m, M_NOWAIT);
        if (bcn->m == NULL) {
                device_printf(sc->sc_dev,
                    "%s: could not copy beacon frame\n", __func__);
                error = ENOMEM;
                goto end;
        }

        if ((error = wpi_cmd2(sc, bcn)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not update beacon frame, error %d", __func__,
                    error);
                m_freem(bcn->m);
        }

        /* Restore mbuf. */
end:    bcn->m = m;

        return error;
}

static int
wpi_setup_beacon(struct wpi_softc *sc, struct ieee80211_node *ni)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct wpi_vap *wvp = WPI_VAP(vap);
        struct wpi_buf *bcn = &wvp->wv_bcbuf;
        struct mbuf *m;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (ni->ni_chan == IEEE80211_CHAN_ANYC)
                return EINVAL;

        m = ieee80211_beacon_alloc(ni);
        if (m == NULL) {
                device_printf(sc->sc_dev,
                    "%s: could not allocate beacon frame\n", __func__);
                return ENOMEM;
        }

        WPI_VAP_LOCK(wvp);
        if (bcn->m != NULL)
                m_freem(bcn->m);

        bcn->m = m;

        error = wpi_config_beacon(wvp);
        WPI_VAP_UNLOCK(wvp);

        return error;
}

static void
wpi_update_beacon(struct ieee80211vap *vap, int item)
{
        struct wpi_softc *sc = vap->iv_ic->ic_softc;
        struct wpi_vap *wvp = WPI_VAP(vap);
        struct wpi_buf *bcn = &wvp->wv_bcbuf;
        struct ieee80211_beacon_offsets *bo = &vap->iv_bcn_off;
        struct ieee80211_node *ni = vap->iv_bss;
        int mcast = 0;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        WPI_VAP_LOCK(wvp);
        if (bcn->m == NULL) {
                bcn->m = ieee80211_beacon_alloc(ni);
                if (bcn->m == NULL) {
                        device_printf(sc->sc_dev,
                            "%s: could not allocate beacon frame\n", __func__);

                        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR,
                            __func__);

                        WPI_VAP_UNLOCK(wvp);
                        return;
                }
        }
        WPI_VAP_UNLOCK(wvp);

        if (item == IEEE80211_BEACON_TIM)
                mcast = 1;      /* TODO */

        setbit(bo->bo_flags, item);
        ieee80211_beacon_update(ni, bcn->m, mcast);

        WPI_VAP_LOCK(wvp);
        wpi_config_beacon(wvp);
        WPI_VAP_UNLOCK(wvp);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);
}

static void
wpi_newassoc(struct ieee80211_node *ni, int isnew)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct wpi_softc *sc = ni->ni_ic->ic_softc;
        struct wpi_node *wn = WPI_NODE(ni);
        int error;

        WPI_NT_LOCK(sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (vap->iv_opmode != IEEE80211_M_STA && wn->id == WPI_ID_UNDEFINED) {
                if ((error = wpi_add_ibss_node(sc, ni)) != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not add IBSS node, error %d\n",
                            __func__, error);
                }
        }
        WPI_NT_UNLOCK(sc);
}

static int
wpi_run(struct wpi_softc *sc, struct ieee80211vap *vap)
{
        struct ieee80211com *ic = vap->iv_ic;
        struct ieee80211_node *ni = vap->iv_bss;
        struct ieee80211_channel *c = ni->ni_chan;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        if (vap->iv_opmode == IEEE80211_M_MONITOR) {
                /* Link LED blinks while monitoring. */
                wpi_set_led(sc, WPI_LED_LINK, 5, 5);
                return 0;
        }

        /* XXX kernel panic workaround */
        if (c == IEEE80211_CHAN_ANYC) {
                device_printf(sc->sc_dev, "%s: incomplete configuration\n",
                    __func__);
                return EINVAL;
        }

        if ((error = wpi_set_timing(sc, ni)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not set timing, error %d\n", __func__, error);
                return error;
        }

        /* Update adapter configuration. */
        WPI_RXON_LOCK(sc);
        IEEE80211_ADDR_COPY(sc->rxon.bssid, ni->ni_bssid);
        sc->rxon.associd = htole16(IEEE80211_NODE_AID(ni));
        sc->rxon.chan = ieee80211_chan2ieee(ic, c);
        sc->rxon.flags = htole32(WPI_RXON_TSF | WPI_RXON_CTS_TO_SELF);
        if (IEEE80211_IS_CHAN_2GHZ(c))
                sc->rxon.flags |= htole32(WPI_RXON_AUTO | WPI_RXON_24GHZ);
        if (ic->ic_flags & IEEE80211_F_SHSLOT)
                sc->rxon.flags |= htole32(WPI_RXON_SHSLOT);
        if (ic->ic_flags & IEEE80211_F_SHPREAMBLE)
                sc->rxon.flags |= htole32(WPI_RXON_SHPREAMBLE);
        if (IEEE80211_IS_CHAN_A(c)) {
                sc->rxon.cck_mask  = 0;
                sc->rxon.ofdm_mask = 0x15;
        } else if (IEEE80211_IS_CHAN_B(c)) {
                sc->rxon.cck_mask  = 0x03;
                sc->rxon.ofdm_mask = 0;
        } else {
                /* Assume 802.11b/g. */
                sc->rxon.cck_mask  = 0x0f;
                sc->rxon.ofdm_mask = 0x15;
        }
        sc->rxon.filter |= htole32(WPI_FILTER_BSS);

        DPRINTF(sc, WPI_DEBUG_STATE, "rxon chan %d flags %x\n",
            sc->rxon.chan, sc->rxon.flags);

        if ((error = wpi_send_rxon(sc, 0, 1)) != 0) {
                WPI_RXON_UNLOCK(sc);
                device_printf(sc->sc_dev, "%s: could not send RXON\n",
                    __func__);
                return error;
        }

        /* Start periodic calibration timer. */
        callout_reset(&sc->calib_to, 60*hz, wpi_calib_timeout, sc);

        WPI_RXON_UNLOCK(sc);

        if (vap->iv_opmode == IEEE80211_M_IBSS ||
            vap->iv_opmode == IEEE80211_M_HOSTAP) {
                if ((error = wpi_setup_beacon(sc, ni)) != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not setup beacon, error %d\n", __func__,
                            error);
                        return error;
                }
        }

        if (vap->iv_opmode == IEEE80211_M_STA) {
                /* Add BSS node. */
                WPI_NT_LOCK(sc);
                error = wpi_add_sta_node(sc, ni);
                WPI_NT_UNLOCK(sc);
                if (error != 0) {
                        device_printf(sc->sc_dev,
                            "%s: could not add BSS node, error %d\n", __func__,
                            error);
                        return error;
                }
        }

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

        /* Enable power-saving mode if requested by user. */
        if ((vap->iv_flags & IEEE80211_F_PMGTON) &&
            vap->iv_opmode != IEEE80211_M_IBSS)
                (void)wpi_set_pslevel(sc, 0, 3, 1);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        return 0;
}

static int
wpi_load_key(struct ieee80211_node *ni, const struct ieee80211_key *k)
{
        const struct ieee80211_cipher *cip = k->wk_cipher;
        struct ieee80211vap *vap = ni->ni_vap;
        struct wpi_softc *sc = ni->ni_ic->ic_softc;
        struct wpi_node *wn = WPI_NODE(ni);
        struct wpi_node_info node;
        uint16_t kflags;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (wpi_check_node_entry(sc, wn->id) == 0) {
                device_printf(sc->sc_dev, "%s: node does not exist\n",
                    __func__);
                return 0;
        }

        switch (cip->ic_cipher) {
        case IEEE80211_CIPHER_AES_CCM:
                kflags = WPI_KFLAG_CCMP;
                break;

        default:
                device_printf(sc->sc_dev, "%s: unknown cipher %d\n", __func__,
                    cip->ic_cipher);
                return 0;
        }

        kflags |= WPI_KFLAG_KID(k->wk_keyix);
        if (k->wk_flags & IEEE80211_KEY_GROUP)
                kflags |= WPI_KFLAG_MULTICAST;

        memset(&node, 0, sizeof node);
        node.id = wn->id;
        node.control = WPI_NODE_UPDATE;
        node.flags = WPI_FLAG_KEY_SET;
        node.kflags = htole16(kflags);
        memcpy(node.key, ieee80211_crypto_get_key_data(k),
            ieee80211_crypto_get_key_len(k));
again:
        DPRINTF(sc, WPI_DEBUG_KEY,
            "%s: setting %s key id %d for node %d (%s)\n", __func__,
            (kflags & WPI_KFLAG_MULTICAST) ? "group" : "ucast", k->wk_keyix,
            node.id, ether_sprintf(ni->ni_macaddr));

        error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
        if (error != 0) {
                device_printf(sc->sc_dev, "can't update node info, error %d\n",
                    error);
                return !error;
        }

        if (!(kflags & WPI_KFLAG_MULTICAST) &&
            ieee80211_is_key_global(vap, k)) {
                kflags |= WPI_KFLAG_MULTICAST;
                node.kflags = htole16(kflags);

                goto again;
        }

        return 1;
}

static void
wpi_load_key_cb(void *arg, struct ieee80211_node *ni)
{
        const struct ieee80211_key *k = arg;
        struct ieee80211vap *vap = ni->ni_vap;
        struct wpi_softc *sc = ni->ni_ic->ic_softc;
        struct wpi_node *wn = WPI_NODE(ni);
        int error;

        if (vap->iv_bss == ni && wn->id == WPI_ID_UNDEFINED)
                return;

        WPI_NT_LOCK(sc);
        error = wpi_load_key(ni, k);
        WPI_NT_UNLOCK(sc);

        if (error == 0) {
                device_printf(sc->sc_dev, "%s: error while setting key\n",
                    __func__);
        }
}

static int
wpi_set_global_keys(struct ieee80211_node *ni)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct ieee80211_key *wk = &vap->iv_nw_keys[0];
        int error = 1;

        for (; wk < &vap->iv_nw_keys[IEEE80211_WEP_NKID] && error; wk++)
                if (wk->wk_keyix != IEEE80211_KEYIX_NONE)
                        error = wpi_load_key(ni, wk);

        return !error;
}

static int
wpi_del_key(struct ieee80211_node *ni, const struct ieee80211_key *k)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct wpi_softc *sc = ni->ni_ic->ic_softc;
        struct wpi_node *wn = WPI_NODE(ni);
        struct wpi_node_info node;
        uint16_t kflags;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (wpi_check_node_entry(sc, wn->id) == 0) {
                DPRINTF(sc, WPI_DEBUG_KEY, "%s: node was removed\n", __func__);
                return 1;       /* Nothing to do. */
        }

        kflags = WPI_KFLAG_KID(k->wk_keyix);
        if (k->wk_flags & IEEE80211_KEY_GROUP)
                kflags |= WPI_KFLAG_MULTICAST;

        memset(&node, 0, sizeof node);
        node.id = wn->id;
        node.control = WPI_NODE_UPDATE;
        node.flags = WPI_FLAG_KEY_SET;
        node.kflags = htole16(kflags);
again:
        DPRINTF(sc, WPI_DEBUG_KEY, "%s: deleting %s key %d for node %d (%s)\n",
            __func__, (kflags & WPI_KFLAG_MULTICAST) ? "group" : "ucast",
            k->wk_keyix, node.id, ether_sprintf(ni->ni_macaddr));

        error = wpi_cmd(sc, WPI_CMD_ADD_NODE, &node, sizeof node, 1);
        if (error != 0) {
                device_printf(sc->sc_dev, "can't update node info, error %d\n",
                    error);
                return !error;
        }

        if (!(kflags & WPI_KFLAG_MULTICAST) &&
            ieee80211_is_key_global(vap, k)) {
                kflags |= WPI_KFLAG_MULTICAST;
                node.kflags = htole16(kflags);

                goto again;
        }

        return 1;
}

static void
wpi_del_key_cb(void *arg, struct ieee80211_node *ni)
{
        const struct ieee80211_key *k = arg;
        struct ieee80211vap *vap = ni->ni_vap;
        struct wpi_softc *sc = ni->ni_ic->ic_softc;
        struct wpi_node *wn = WPI_NODE(ni);
        int error;

        if (vap->iv_bss == ni && wn->id == WPI_ID_UNDEFINED)
                return;

        WPI_NT_LOCK(sc);
        error = wpi_del_key(ni, k);
        WPI_NT_UNLOCK(sc);

        if (error == 0) {
                device_printf(sc->sc_dev, "%s: error while deleting key\n",
                    __func__);
        }
}

static int
wpi_process_key(struct ieee80211vap *vap, const struct ieee80211_key *k,
    int set)
{
        struct ieee80211com *ic = vap->iv_ic;
        struct wpi_softc *sc = ic->ic_softc;
        struct wpi_vap *wvp = WPI_VAP(vap);
        struct ieee80211_node *ni;
        int error, ni_ref = 0;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (k->wk_flags & IEEE80211_KEY_SWCRYPT) {
                /* Not for us. */
                return 1;
        }

        if (!(k->wk_flags & IEEE80211_KEY_RECV)) {
                /* XMIT keys are handled in wpi_tx_data(). */
                return 1;
        }

        /* Handle group keys. */
        if (ieee80211_is_key_global(vap, k)) {
                WPI_NT_LOCK(sc);
                if (set)
                        wvp->wv_gtk |= WPI_VAP_KEY(k->wk_keyix);
                else
                        wvp->wv_gtk &= ~WPI_VAP_KEY(k->wk_keyix);
                WPI_NT_UNLOCK(sc);

                if (vap->iv_state == IEEE80211_S_RUN) {
                        ieee80211_iterate_nodes(&ic->ic_sta,
                            set ? wpi_load_key_cb : wpi_del_key_cb,
                            __DECONST(void *, k));
                }

                return 1;
        }

        switch (vap->iv_opmode) {
        case IEEE80211_M_STA:
                ni = vap->iv_bss;
                break;

        case IEEE80211_M_IBSS:
        case IEEE80211_M_AHDEMO:
        case IEEE80211_M_HOSTAP:
                ni = ieee80211_find_vap_node(&ic->ic_sta, vap, k->wk_macaddr);
                if (ni == NULL)
                        return 0;       /* should not happen */

                ni_ref = 1;
                break;

        default:
                device_printf(sc->sc_dev, "%s: unknown opmode %d\n", __func__,
                    vap->iv_opmode);
                return 0;
        }

        WPI_NT_LOCK(sc);
        if (set)
                error = wpi_load_key(ni, k);
        else
                error = wpi_del_key(ni, k);
        WPI_NT_UNLOCK(sc);

        if (ni_ref)
                ieee80211_node_decref(ni);

        return error;
}

static int
wpi_key_set(struct ieee80211vap *vap, const struct ieee80211_key *k)
{
        return wpi_process_key(vap, k, 1);
}

static int
wpi_key_delete(struct ieee80211vap *vap, const struct ieee80211_key *k)
{
        return wpi_process_key(vap, k, 0);
}

/*
 * This function is called after the runtime firmware notifies us of its
 * readiness (called in a process context).
 */
static int
wpi_post_alive(struct wpi_softc *sc)
{
        int ntries, error;

        /* Check (again) that the radio is not disabled. */
        if ((error = wpi_nic_lock(sc)) != 0)
                return error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        /* NB: Runtime firmware must be up and running. */
        if (!(wpi_prph_read(sc, WPI_APMG_RFKILL) & 1)) {
                device_printf(sc->sc_dev,
                    "RF switch: radio disabled (%s)\n", __func__);
                wpi_nic_unlock(sc);
                return EPERM;   /* :-) */
        }
        wpi_nic_unlock(sc);

        /* Wait for thermal sensor to calibrate. */
        for (ntries = 0; ntries < 1000; ntries++) {
                if ((sc->temp = (int)WPI_READ(sc, WPI_UCODE_GP2)) != 0)
                        break;
                DELAY(10);
        }

        if (ntries == 1000) {
                device_printf(sc->sc_dev,
                    "timeout waiting for thermal sensor calibration\n");
                return ETIMEDOUT;
        }

        DPRINTF(sc, WPI_DEBUG_TEMP, "temperature %d\n", sc->temp);
        return 0;
}

/*
 * The firmware boot code is small and is intended to be copied directly into
 * the NIC internal memory (no DMA transfer).
 */
static int
wpi_load_bootcode(struct wpi_softc *sc, const uint8_t *ucode, uint32_t size)
{
        int error, ntries;

        DPRINTF(sc, WPI_DEBUG_HW, "Loading microcode size 0x%x\n", size);

        size /= sizeof (uint32_t);

        if ((error = wpi_nic_lock(sc)) != 0)
                return error;

        /* Copy microcode image into NIC memory. */
        wpi_prph_write_region_4(sc, WPI_BSM_SRAM_BASE,
            (const uint32_t *)ucode, size);

        wpi_prph_write(sc, WPI_BSM_WR_MEM_SRC, 0);
        wpi_prph_write(sc, WPI_BSM_WR_MEM_DST, WPI_FW_TEXT_BASE);
        wpi_prph_write(sc, WPI_BSM_WR_DWCOUNT, size);

        /* Start boot load now. */
        wpi_prph_write(sc, WPI_BSM_WR_CTRL, WPI_BSM_WR_CTRL_START);

        /* Wait for transfer to complete. */
        for (ntries = 0; ntries < 1000; ntries++) {
                uint32_t status = WPI_READ(sc, WPI_FH_TX_STATUS);
                DPRINTF(sc, WPI_DEBUG_HW,
                    "firmware status=0x%x, val=0x%x, result=0x%x\n", status,
                    WPI_FH_TX_STATUS_IDLE(6),
                    status & WPI_FH_TX_STATUS_IDLE(6));
                if (status & WPI_FH_TX_STATUS_IDLE(6)) {
                        DPRINTF(sc, WPI_DEBUG_HW,
                            "Status Match! - ntries = %d\n", ntries);
                        break;
                }
                DELAY(10);
        }
        if (ntries == 1000) {
                device_printf(sc->sc_dev, "%s: could not load boot firmware\n",
                    __func__);
                wpi_nic_unlock(sc);
                return ETIMEDOUT;
        }

        /* Enable boot after power up. */
        wpi_prph_write(sc, WPI_BSM_WR_CTRL, WPI_BSM_WR_CTRL_START_EN);

        wpi_nic_unlock(sc);
        return 0;
}

static int
wpi_load_firmware(struct wpi_softc *sc)
{
        struct wpi_fw_info *fw = &sc->fw;
        struct wpi_dma_info *dma = &sc->fw_dma;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        /* Copy initialization sections into pre-allocated DMA-safe memory. */
        memcpy(dma->vaddr, fw->init.data, fw->init.datasz);
        bus_dmamap_sync(dma->tag, dma->map, BUS_DMASYNC_PREWRITE);
        memcpy(dma->vaddr + WPI_FW_DATA_MAXSZ, fw->init.text, fw->init.textsz);
        bus_dmamap_sync(dma->tag, dma->map, BUS_DMASYNC_PREWRITE);

        /* Tell adapter where to find initialization sections. */
        if ((error = wpi_nic_lock(sc)) != 0)
                return error;
        wpi_prph_write(sc, WPI_BSM_DRAM_DATA_ADDR, dma->paddr);
        wpi_prph_write(sc, WPI_BSM_DRAM_DATA_SIZE, fw->init.datasz);
        wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_ADDR,
            dma->paddr + WPI_FW_DATA_MAXSZ);
        wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_SIZE, fw->init.textsz);
        wpi_nic_unlock(sc);

        /* Load firmware boot code. */
        error = wpi_load_bootcode(sc, fw->boot.text, fw->boot.textsz);
        if (error != 0) {
                device_printf(sc->sc_dev, "%s: could not load boot firmware\n",
                    __func__);
                return error;
        }

        /* Now press "execute". */
        WPI_WRITE(sc, WPI_RESET, 0);

        /* Wait at most one second for first alive notification. */
        if ((error = mtx_sleep(sc, &sc->sc_mtx, PCATCH, "wpiinit", hz)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: timeout waiting for adapter to initialize, error %d\n",
                    __func__, error);
                return error;
        }

        /* Copy runtime sections into pre-allocated DMA-safe memory. */
        memcpy(dma->vaddr, fw->main.data, fw->main.datasz);
        bus_dmamap_sync(dma->tag, dma->map, BUS_DMASYNC_PREWRITE);
        memcpy(dma->vaddr + WPI_FW_DATA_MAXSZ, fw->main.text, fw->main.textsz);
        bus_dmamap_sync(dma->tag, dma->map, BUS_DMASYNC_PREWRITE);

        /* Tell adapter where to find runtime sections. */
        if ((error = wpi_nic_lock(sc)) != 0)
                return error;
        wpi_prph_write(sc, WPI_BSM_DRAM_DATA_ADDR, dma->paddr);
        wpi_prph_write(sc, WPI_BSM_DRAM_DATA_SIZE, fw->main.datasz);
        wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_ADDR,
            dma->paddr + WPI_FW_DATA_MAXSZ);
        wpi_prph_write(sc, WPI_BSM_DRAM_TEXT_SIZE,
            WPI_FW_UPDATED | fw->main.textsz);
        wpi_nic_unlock(sc);

        return 0;
}

static int
wpi_read_firmware(struct wpi_softc *sc)
{
        const struct firmware *fp;
        struct wpi_fw_info *fw = &sc->fw;
        const struct wpi_firmware_hdr *hdr;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        DPRINTF(sc, WPI_DEBUG_FIRMWARE,
            "Attempting Loading Firmware from %s module\n", WPI_FW_NAME);

        WPI_UNLOCK(sc);
        fp = firmware_get(WPI_FW_NAME);
        WPI_LOCK(sc);

        if (fp == NULL) {
                device_printf(sc->sc_dev,
                    "could not load firmware image '%s'\n", WPI_FW_NAME);
                return EINVAL;
        }

        sc->fw_fp = fp;

        if (fp->datasize < sizeof (struct wpi_firmware_hdr)) {
                device_printf(sc->sc_dev,
                    "firmware file too short: %zu bytes\n", fp->datasize);
                error = EINVAL;
                goto fail;
        }

        fw->size = fp->datasize;
        fw->data = (const uint8_t *)fp->data;

        /* Extract firmware header information. */
        hdr = (const struct wpi_firmware_hdr *)fw->data;

        /*     |  RUNTIME FIRMWARE   |    INIT FIRMWARE    | BOOT FW  |
           |HDR|<--TEXT-->|<--DATA-->|<--TEXT-->|<--DATA-->|<--TEXT-->| */

        fw->main.textsz = le32toh(hdr->rtextsz);
        fw->main.datasz = le32toh(hdr->rdatasz);
        fw->init.textsz = le32toh(hdr->itextsz);
        fw->init.datasz = le32toh(hdr->idatasz);
        fw->boot.textsz = le32toh(hdr->btextsz);
        fw->boot.datasz = 0;

        /* Sanity-check firmware header. */
        if (fw->main.textsz > WPI_FW_TEXT_MAXSZ ||
            fw->main.datasz > WPI_FW_DATA_MAXSZ ||
            fw->init.textsz > WPI_FW_TEXT_MAXSZ ||
            fw->init.datasz > WPI_FW_DATA_MAXSZ ||
            fw->boot.textsz > WPI_FW_BOOT_TEXT_MAXSZ ||
            (fw->boot.textsz & 3) != 0) {
                device_printf(sc->sc_dev, "invalid firmware header\n");
                error = EINVAL;
                goto fail;
        }

        /* Check that all firmware sections fit. */
        if (fw->size < sizeof (*hdr) + fw->main.textsz + fw->main.datasz +
            fw->init.textsz + fw->init.datasz + fw->boot.textsz) {
                device_printf(sc->sc_dev,
                    "firmware file too short: %zu bytes\n", fw->size);
                error = EINVAL;
                goto fail;
        }

        /* Get pointers to firmware sections. */
        fw->main.text = (const uint8_t *)(hdr + 1);
        fw->main.data = fw->main.text + fw->main.textsz;
        fw->init.text = fw->main.data + fw->main.datasz;
        fw->init.data = fw->init.text + fw->init.textsz;
        fw->boot.text = fw->init.data + fw->init.datasz;

        DPRINTF(sc, WPI_DEBUG_FIRMWARE,
            "Firmware Version: Major %d, Minor %d, Driver %d, \n"
            "runtime (text: %u, data: %u) init (text: %u, data %u) "
            "boot (text %u)\n", hdr->major, hdr->minor, le32toh(hdr->driver),
            fw->main.textsz, fw->main.datasz,
            fw->init.textsz, fw->init.datasz, fw->boot.textsz);

        DPRINTF(sc, WPI_DEBUG_FIRMWARE, "fw->main.text %p\n", fw->main.text);
        DPRINTF(sc, WPI_DEBUG_FIRMWARE, "fw->main.data %p\n", fw->main.data);
        DPRINTF(sc, WPI_DEBUG_FIRMWARE, "fw->init.text %p\n", fw->init.text);
        DPRINTF(sc, WPI_DEBUG_FIRMWARE, "fw->init.data %p\n", fw->init.data);
        DPRINTF(sc, WPI_DEBUG_FIRMWARE, "fw->boot.text %p\n", fw->boot.text);

        return 0;

fail:   wpi_unload_firmware(sc);
        return error;
}

/**
 * Free the referenced firmware image
 */
static void
wpi_unload_firmware(struct wpi_softc *sc)
{
        if (sc->fw_fp != NULL) {
                firmware_put(sc->fw_fp, FIRMWARE_UNLOAD);
                sc->fw_fp = NULL;
        }
}

static int
wpi_clock_wait(struct wpi_softc *sc)
{
        int ntries;

        /* Set "initialization complete" bit. */
        WPI_SETBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_INIT_DONE);

        /* Wait for clock stabilization. */
        for (ntries = 0; ntries < 2500; ntries++) {
                if (WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_MAC_CLOCK_READY)
                        return 0;
                DELAY(100);
        }
        device_printf(sc->sc_dev,
            "%s: timeout waiting for clock stabilization\n", __func__);

        return ETIMEDOUT;
}

static int
wpi_apm_init(struct wpi_softc *sc)
{
        uint32_t reg;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        /* Disable L0s exit timer (NMI bug workaround). */
        WPI_SETBITS(sc, WPI_GIO_CHICKEN, WPI_GIO_CHICKEN_DIS_L0S_TIMER);
        /* Don't wait for ICH L0s (ICH bug workaround). */
        WPI_SETBITS(sc, WPI_GIO_CHICKEN, WPI_GIO_CHICKEN_L1A_NO_L0S_RX);

        /* Set FH wait threshold to max (HW bug under stress workaround). */
        WPI_SETBITS(sc, WPI_DBG_HPET_MEM, 0xffff0000);

        /* Retrieve PCIe Active State Power Management (ASPM). */
        reg = pci_read_config(sc->sc_dev, sc->sc_cap_off + PCIER_LINK_CTL, 1);
        /* Workaround for HW instability in PCIe L0->L0s->L1 transition. */
        if (reg & PCIEM_LINK_CTL_ASPMC_L1)      /* L1 Entry enabled. */
                WPI_SETBITS(sc, WPI_GIO, WPI_GIO_L0S_ENA);
        else
                WPI_CLRBITS(sc, WPI_GIO, WPI_GIO_L0S_ENA);

        WPI_SETBITS(sc, WPI_ANA_PLL, WPI_ANA_PLL_INIT);

        /* Wait for clock stabilization before accessing prph. */
        if ((error = wpi_clock_wait(sc)) != 0)
                return error;

        if ((error = wpi_nic_lock(sc)) != 0)
                return error;
        /* Cleanup. */
        wpi_prph_write(sc, WPI_APMG_CLK_DIS, 0x00000400);
        wpi_prph_clrbits(sc, WPI_APMG_PS, 0x00000200);

        /* Enable DMA and BSM (Bootstrap State Machine). */
        wpi_prph_write(sc, WPI_APMG_CLK_EN,
            WPI_APMG_CLK_CTRL_DMA_CLK_RQT | WPI_APMG_CLK_CTRL_BSM_CLK_RQT);
        DELAY(20);
        /* Disable L1-Active. */
        wpi_prph_setbits(sc, WPI_APMG_PCI_STT, WPI_APMG_PCI_STT_L1A_DIS);
        wpi_nic_unlock(sc);

        return 0;
}

static void
wpi_apm_stop_master(struct wpi_softc *sc)
{
        int ntries;

        /* Stop busmaster DMA activity. */
        WPI_SETBITS(sc, WPI_RESET, WPI_RESET_STOP_MASTER);

        if ((WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_PS_MASK) ==
            WPI_GP_CNTRL_MAC_PS)
                return; /* Already asleep. */

        for (ntries = 0; ntries < 100; ntries++) {
                if (WPI_READ(sc, WPI_RESET) & WPI_RESET_MASTER_DISABLED)
                        return;
                DELAY(10);
        }
        device_printf(sc->sc_dev, "%s: timeout waiting for master\n",
            __func__);
}

static void
wpi_apm_stop(struct wpi_softc *sc)
{
        wpi_apm_stop_master(sc);

        /* Reset the entire device. */
        WPI_SETBITS(sc, WPI_RESET, WPI_RESET_SW);
        DELAY(10);
        /* Clear "initialization complete" bit. */
        WPI_CLRBITS(sc, WPI_GP_CNTRL, WPI_GP_CNTRL_INIT_DONE);
}

static void
wpi_nic_config(struct wpi_softc *sc)
{
        uint32_t rev;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        /* voodoo from the Linux "driver".. */
        rev = pci_read_config(sc->sc_dev, PCIR_REVID, 1);
        if ((rev & 0xc0) == 0x40)
                WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_ALM_MB);
        else if (!(rev & 0x80))
                WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_ALM_MM);

        if (sc->cap == 0x80)
                WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_SKU_MRC);

        if ((sc->rev & 0xf0) == 0xd0)
                WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_REV_D);
        else
                WPI_CLRBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_REV_D);

        if (sc->type > 1)
                WPI_SETBITS(sc, WPI_HW_IF_CONFIG, WPI_HW_IF_CONFIG_TYPE_B);
}

static int
wpi_hw_init(struct wpi_softc *sc)
{
        uint8_t chnl;
        int ntries, error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        /* Clear pending interrupts. */
        WPI_WRITE(sc, WPI_INT, 0xffffffff);

        if ((error = wpi_apm_init(sc)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not power ON adapter, error %d\n", __func__,
                    error);
                return error;
        }

        /* Select VMAIN power source. */
        if ((error = wpi_nic_lock(sc)) != 0)
                return error;
        wpi_prph_clrbits(sc, WPI_APMG_PS, WPI_APMG_PS_PWR_SRC_MASK);
        wpi_nic_unlock(sc);
        /* Spin until VMAIN gets selected. */
        for (ntries = 0; ntries < 5000; ntries++) {
                if (WPI_READ(sc, WPI_GPIO_IN) & WPI_GPIO_IN_VMAIN)
                        break;
                DELAY(10);
        }
        if (ntries == 5000) {
                device_printf(sc->sc_dev, "timeout selecting power source\n");
                return ETIMEDOUT;
        }

        /* Perform adapter initialization. */
        wpi_nic_config(sc);

        /* Initialize RX ring. */
        if ((error = wpi_nic_lock(sc)) != 0)
                return error;
        /* Set physical address of RX ring. */
        WPI_WRITE(sc, WPI_FH_RX_BASE, sc->rxq.desc_dma.paddr);
        /* Set physical address of RX read pointer. */
        WPI_WRITE(sc, WPI_FH_RX_RPTR_ADDR, sc->shared_dma.paddr +
            offsetof(struct wpi_shared, next));
        WPI_WRITE(sc, WPI_FH_RX_WPTR, 0);
        /* Enable RX. */
        WPI_WRITE(sc, WPI_FH_RX_CONFIG,
            WPI_FH_RX_CONFIG_DMA_ENA |
            WPI_FH_RX_CONFIG_RDRBD_ENA |
            WPI_FH_RX_CONFIG_WRSTATUS_ENA |
            WPI_FH_RX_CONFIG_MAXFRAG |
            WPI_FH_RX_CONFIG_NRBD(WPI_RX_RING_COUNT_LOG) |
            WPI_FH_RX_CONFIG_IRQ_DST_HOST |
            WPI_FH_RX_CONFIG_IRQ_TIMEOUT(1));
        (void)WPI_READ(sc, WPI_FH_RSSR_TBL);    /* barrier */
        wpi_nic_unlock(sc);
        WPI_WRITE(sc, WPI_FH_RX_WPTR, (WPI_RX_RING_COUNT - 1) & ~7);

        /* Initialize TX rings. */
        if ((error = wpi_nic_lock(sc)) != 0)
                return error;
        wpi_prph_write(sc, WPI_ALM_SCHED_MODE, 2);      /* bypass mode */
        wpi_prph_write(sc, WPI_ALM_SCHED_ARASTAT, 1);   /* enable RA0 */
        /* Enable all 6 TX rings. */
        wpi_prph_write(sc, WPI_ALM_SCHED_TXFACT, 0x3f);
        wpi_prph_write(sc, WPI_ALM_SCHED_SBYPASS_MODE1, 0x10000);
        wpi_prph_write(sc, WPI_ALM_SCHED_SBYPASS_MODE2, 0x30002);
        wpi_prph_write(sc, WPI_ALM_SCHED_TXF4MF, 4);
        wpi_prph_write(sc, WPI_ALM_SCHED_TXF5MF, 5);
        /* Set physical address of TX rings. */
        WPI_WRITE(sc, WPI_FH_TX_BASE, sc->shared_dma.paddr);
        WPI_WRITE(sc, WPI_FH_MSG_CONFIG, 0xffff05a5);

        /* Enable all DMA channels. */
        for (chnl = 0; chnl < WPI_NDMACHNLS; chnl++) {
                WPI_WRITE(sc, WPI_FH_CBBC_CTRL(chnl), 0);
                WPI_WRITE(sc, WPI_FH_CBBC_BASE(chnl), 0);
                WPI_WRITE(sc, WPI_FH_TX_CONFIG(chnl), 0x80200008);
        }
        wpi_nic_unlock(sc);
        (void)WPI_READ(sc, WPI_FH_TX_BASE);     /* barrier */

        /* Clear "radio off" and "commands blocked" bits. */
        WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_RFKILL);
        WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_CMD_BLOCKED);

        /* Clear pending interrupts. */
        WPI_WRITE(sc, WPI_INT, 0xffffffff);
        /* Enable interrupts. */
        WPI_WRITE(sc, WPI_INT_MASK, WPI_INT_MASK_DEF);

        /* _Really_ make sure "radio off" bit is cleared! */
        WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_RFKILL);
        WPI_WRITE(sc, WPI_UCODE_GP1_CLR, WPI_UCODE_GP1_RFKILL);

        if ((error = wpi_load_firmware(sc)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not load firmware, error %d\n", __func__,
                    error);
                return error;
        }
        /* Wait at most one second for firmware alive notification. */
        if ((error = mtx_sleep(sc, &sc->sc_mtx, PCATCH, "wpiinit", hz)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: timeout waiting for adapter to initialize, error %d\n",
                    __func__, error);
                return error;
        }

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        /* Do post-firmware initialization. */
        return wpi_post_alive(sc);
}

static void
wpi_hw_stop(struct wpi_softc *sc)
{
        uint8_t chnl, qid;
        int ntries;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        if (WPI_READ(sc, WPI_UCODE_GP1) & WPI_UCODE_GP1_MAC_SLEEP)
                wpi_nic_lock(sc);

        WPI_WRITE(sc, WPI_RESET, WPI_RESET_NEVO);

        /* Disable interrupts. */
        WPI_WRITE(sc, WPI_INT_MASK, 0);
        WPI_WRITE(sc, WPI_INT, 0xffffffff);
        WPI_WRITE(sc, WPI_FH_INT, 0xffffffff);

        /* Make sure we no longer hold the NIC lock. */
        wpi_nic_unlock(sc);

        if (wpi_nic_lock(sc) == 0) {
                /* Stop TX scheduler. */
                wpi_prph_write(sc, WPI_ALM_SCHED_MODE, 0);
                wpi_prph_write(sc, WPI_ALM_SCHED_TXFACT, 0);

                /* Stop all DMA channels. */
                for (chnl = 0; chnl < WPI_NDMACHNLS; chnl++) {
                        WPI_WRITE(sc, WPI_FH_TX_CONFIG(chnl), 0);
                        for (ntries = 0; ntries < 200; ntries++) {
                                if (WPI_READ(sc, WPI_FH_TX_STATUS) &
                                    WPI_FH_TX_STATUS_IDLE(chnl))
                                        break;
                                DELAY(10);
                        }
                }
                wpi_nic_unlock(sc);
        }

        /* Stop RX ring. */
        wpi_reset_rx_ring(sc);

        /* Reset all TX rings. */
        for (qid = 0; qid < WPI_DRV_NTXQUEUES; qid++)
                wpi_reset_tx_ring(sc, &sc->txq[qid]);

        if (wpi_nic_lock(sc) == 0) {
                wpi_prph_write(sc, WPI_APMG_CLK_DIS,
                    WPI_APMG_CLK_CTRL_DMA_CLK_RQT);
                wpi_nic_unlock(sc);
        }
        DELAY(5);
        /* Power OFF adapter. */
        wpi_apm_stop(sc);
}

static void
wpi_radio_on(void *arg0, int pending)
{
        struct wpi_softc *sc = arg0;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);

        device_printf(sc->sc_dev, "RF switch: radio enabled\n");

        WPI_LOCK(sc);
        callout_stop(&sc->watchdog_rfkill);
        WPI_UNLOCK(sc);

        if (vap != NULL)
                ieee80211_init(vap);
}

static void
wpi_radio_off(void *arg0, int pending)
{
        struct wpi_softc *sc = arg0;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);

        device_printf(sc->sc_dev, "RF switch: radio disabled\n");

        ieee80211_notify_radio(ic, 0);
        wpi_stop(sc);
        if (vap != NULL)
                ieee80211_stop(vap);

        WPI_LOCK(sc);
        callout_reset(&sc->watchdog_rfkill, hz, wpi_watchdog_rfkill, sc);
        WPI_UNLOCK(sc);
}

static int
wpi_init(struct wpi_softc *sc)
{
        int error = 0;

        WPI_LOCK(sc);

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_BEGIN, __func__);

        if (sc->sc_running != 0)
                goto end;

        /* Check that the radio is not disabled by hardware switch. */
        if (!(WPI_READ(sc, WPI_GP_CNTRL) & WPI_GP_CNTRL_RFKILL)) {
                device_printf(sc->sc_dev,
                    "RF switch: radio disabled (%s)\n", __func__);
                callout_reset(&sc->watchdog_rfkill, hz, wpi_watchdog_rfkill,
                    sc);
                error = EINPROGRESS;
                goto end;
        }

        /* Read firmware images from the filesystem. */
        if ((error = wpi_read_firmware(sc)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not read firmware, error %d\n", __func__,
                    error);
                goto end;
        }

        sc->sc_running = 1;

        /* Initialize hardware and upload firmware. */
        error = wpi_hw_init(sc);
        wpi_unload_firmware(sc);
        if (error != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not initialize hardware, error %d\n", __func__,
                    error);
                goto fail;
        }

        /* Configure adapter now that it is ready. */
        if ((error = wpi_config(sc)) != 0) {
                device_printf(sc->sc_dev,
                    "%s: could not configure device, error %d\n", __func__,
                    error);
                goto fail;
        }

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END, __func__);

        WPI_UNLOCK(sc);

        return 0;

fail:   wpi_stop_locked(sc);

end:    DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_END_ERR, __func__);
        WPI_UNLOCK(sc);

        return error;
}

static void
wpi_stop_locked(struct wpi_softc *sc)
{

        WPI_LOCK_ASSERT(sc);

        if (sc->sc_running == 0)
                return;

        WPI_TX_LOCK(sc);
        WPI_TXQ_LOCK(sc);
        sc->sc_running = 0;
        WPI_TXQ_UNLOCK(sc);
        WPI_TX_UNLOCK(sc);

        WPI_TXQ_STATE_LOCK(sc);
        callout_stop(&sc->tx_timeout);
        WPI_TXQ_STATE_UNLOCK(sc);

        WPI_RXON_LOCK(sc);
        callout_stop(&sc->scan_timeout);
        callout_stop(&sc->calib_to);
        WPI_RXON_UNLOCK(sc);

        /* Power OFF hardware. */
        wpi_hw_stop(sc);
}

static void
wpi_stop(struct wpi_softc *sc)
{
        WPI_LOCK(sc);
        wpi_stop_locked(sc);
        WPI_UNLOCK(sc);
}

/*
 * Callback from net80211 to start a scan.
 */
static void
wpi_scan_start(struct ieee80211com *ic)
{
        struct wpi_softc *sc = ic->ic_softc;

        wpi_set_led(sc, WPI_LED_LINK, 20, 2);
}

/*
 * Callback from net80211 to terminate a scan.
 */
static void
wpi_scan_end(struct ieee80211com *ic)
{
        struct wpi_softc *sc = ic->ic_softc;
        struct ieee80211vap *vap = TAILQ_FIRST(&ic->ic_vaps);

        if (vap->iv_state == IEEE80211_S_RUN)
                wpi_set_led(sc, WPI_LED_LINK, 0, 1);
}

/**
 * Called by the net80211 framework to indicate to the driver
 * that the channel should be changed
 */
static void
wpi_set_channel(struct ieee80211com *ic)
{
        const struct ieee80211_channel *c = ic->ic_curchan;
        struct wpi_softc *sc = ic->ic_softc;
        int error;

        DPRINTF(sc, WPI_DEBUG_TRACE, TRACE_STR_DOING, __func__);

        WPI_LOCK(sc);
        sc->sc_rxtap.wr_chan_freq = htole16(c->ic_freq);
        sc->sc_rxtap.wr_chan_flags = htole16(c->ic_flags);
        WPI_UNLOCK(sc);
        WPI_TX_LOCK(sc);
        sc->sc_txtap.wt_chan_freq = htole16(c->ic_freq);
        sc->sc_txtap.wt_chan_flags = htole16(c->ic_flags);
        WPI_TX_UNLOCK(sc);

        /*
         * Only need to set the channel in Monitor mode. AP scanning and auth
         * are already taken care of by their respective firmware commands.
         */
        if (ic->ic_opmode == IEEE80211_M_MONITOR) {
                WPI_RXON_LOCK(sc);
                sc->rxon.chan = ieee80211_chan2ieee(ic, c);
                if (IEEE80211_IS_CHAN_2GHZ(c)) {
                        sc->rxon.flags |= htole32(WPI_RXON_AUTO |
                            WPI_RXON_24GHZ);
                } else {
                        sc->rxon.flags &= ~htole32(WPI_RXON_AUTO |
                            WPI_RXON_24GHZ);
                }
                if ((error = wpi_send_rxon(sc, 0, 1)) != 0)
                        device_printf(sc->sc_dev,
                            "%s: error %d setting channel\n", __func__,
                            error);
                WPI_RXON_UNLOCK(sc);
        }
}

/**
 * Called by net80211 to indicate that we need to scan the current
 * channel. The channel is previously be set via the wpi_set_channel
 * callback.
 */
static void
wpi_scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell)
{
        struct ieee80211vap *vap = ss->ss_vap;
        struct ieee80211com *ic = vap->iv_ic;
        struct wpi_softc *sc = ic->ic_softc;
        int error;

        WPI_RXON_LOCK(sc);
        error = wpi_scan(sc, ic->ic_curchan);
        WPI_RXON_UNLOCK(sc);
        if (error != 0)
                ieee80211_cancel_scan(vap);
}

/**
 * Called by the net80211 framework to indicate
 * the minimum dwell time has been met, terminate the scan.
 * We don't actually terminate the scan as the firmware will notify
 * us when it's finished and we have no way to interrupt it.
 */
static void
wpi_scan_mindwell(struct ieee80211_scan_state *ss)
{
        /* NB: don't try to abort scan; wait for firmware to finish */
}