/*      $NetBSD: rt2560.c,v 1.41 2025/07/15 22:15:04 andvar Exp $       */
/*      $OpenBSD: rt2560.c,v 1.15 2006/04/20 20:31:12 miod Exp $  */
/*      $FreeBSD: rt2560.c,v 1.3 2006/03/21 21:15:43 damien Exp $*/

/*-
 * Copyright (c) 2005, 2006
 *      Damien Bergamini <damien.bergamini@free.fr>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*-
 * Ralink Technology RT2560 chipset driver
 * http://www.ralinktech.com/
 */
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rt2560.c,v 1.41 2025/07/15 22:15:04 andvar Exp $");


#include <sys/param.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/callout.h>
#include <sys/conf.h>
#include <sys/device.h>

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

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

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

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_rssadapt.h>
#include <net80211/ieee80211_radiotap.h>

#include <dev/ic/rt2560reg.h>
#include <dev/ic/rt2560var.h>

#ifdef RAL_DEBUG
#define DPRINTF(x)      do { if (rt2560_debug > 0) printf x; } while (0)
#define DPRINTFN(n, x)  do { if (rt2560_debug >= (n)) printf x; } while (0)
int rt2560_debug = 0;
#else
#define DPRINTF(x)
#define DPRINTFN(n, x)
#endif

static int      rt2560_alloc_tx_ring(struct rt2560_softc *, 
                    struct rt2560_tx_ring *, int);
static void     rt2560_reset_tx_ring(struct rt2560_softc *,
                    struct rt2560_tx_ring *);
static void     rt2560_free_tx_ring(struct rt2560_softc *,
                    struct rt2560_tx_ring *);
static int      rt2560_alloc_rx_ring(struct rt2560_softc *,
                    struct rt2560_rx_ring *, int);
static void     rt2560_reset_rx_ring(struct rt2560_softc *,
                    struct rt2560_rx_ring *);
static void     rt2560_free_rx_ring(struct rt2560_softc *,
                    struct rt2560_rx_ring *);
static struct ieee80211_node *
                rt2560_node_alloc(struct ieee80211_node_table *);
static int      rt2560_media_change(struct ifnet *);
static void     rt2560_next_scan(void *);
static void     rt2560_iter_func(void *, struct ieee80211_node *);
static void     rt2560_update_rssadapt(void *);
static int      rt2560_newstate(struct ieee80211com *, enum ieee80211_state,
                    int);
static uint16_t rt2560_eeprom_read(struct rt2560_softc *, uint8_t);
static void     rt2560_encryption_intr(struct rt2560_softc *);
static void     rt2560_tx_intr(struct rt2560_softc *);
static void     rt2560_prio_intr(struct rt2560_softc *);
static void     rt2560_decryption_intr(struct rt2560_softc *);
static void     rt2560_rx_intr(struct rt2560_softc *);
static void     rt2560_beacon_expire(struct rt2560_softc *);
static void     rt2560_wakeup_expire(struct rt2560_softc *);
static uint8_t  rt2560_rxrate(struct rt2560_rx_desc *);
static int      rt2560_ack_rate(struct ieee80211com *, int);
static uint16_t rt2560_txtime(int, int, uint32_t);
static uint8_t  rt2560_plcp_signal(int);
static void     rt2560_setup_tx_desc(struct rt2560_softc *,
                    struct rt2560_tx_desc *, uint32_t, int, int, int, 
                    bus_addr_t);
static int      rt2560_tx_bcn(struct rt2560_softc *, struct mbuf *,
                    struct ieee80211_node *);
static int      rt2560_tx_mgt(struct rt2560_softc *, struct mbuf *,
                    struct ieee80211_node *);
static struct mbuf *rt2560_get_rts(struct rt2560_softc *,
                    struct ieee80211_frame *, uint16_t);
static int      rt2560_tx_data(struct rt2560_softc *, struct mbuf *,
                    struct ieee80211_node *);
static void     rt2560_start(struct ifnet *);
static void     rt2560_watchdog(struct ifnet *);
static int      rt2560_reset(struct ifnet *);
static int      rt2560_ioctl(struct ifnet *, u_long, void *);
static void     rt2560_bbp_write(struct rt2560_softc *, uint8_t, uint8_t);
static uint8_t  rt2560_bbp_read(struct rt2560_softc *, uint8_t);
static void     rt2560_rf_write(struct rt2560_softc *, uint8_t, uint32_t);
static void     rt2560_set_chan(struct rt2560_softc *,
                    struct ieee80211_channel *);
static void     rt2560_disable_rf_tune(struct rt2560_softc *);
static void     rt2560_enable_tsf_sync(struct rt2560_softc *);
static void     rt2560_update_plcp(struct rt2560_softc *);
static void     rt2560_update_slot(struct ifnet *);
static void     rt2560_set_basicrates(struct rt2560_softc *);
static void     rt2560_update_led(struct rt2560_softc *, int, int);
static void     rt2560_set_bssid(struct rt2560_softc *, uint8_t *);
static void     rt2560_set_macaddr(struct rt2560_softc *, uint8_t *);
static void     rt2560_get_macaddr(struct rt2560_softc *, uint8_t *);
static void     rt2560_update_promisc(struct rt2560_softc *);
static void     rt2560_set_txantenna(struct rt2560_softc *, int);
static void     rt2560_set_rxantenna(struct rt2560_softc *, int);
static const char *rt2560_get_rf(int);
static void     rt2560_read_eeprom(struct rt2560_softc *);
static int      rt2560_bbp_init(struct rt2560_softc *);
static int      rt2560_init(struct ifnet *);
static void     rt2560_stop(struct ifnet *, int);
static void     rt2560_softintr(void *);

/*
 * Default values for MAC registers; values taken from the reference driver.
 */
static const struct {
        uint32_t        reg;
        uint32_t        val;
} rt2560_def_mac[] = {
        { RT2560_PSCSR0,      0x00020002 },
        { RT2560_PSCSR1,      0x00000002 },
        { RT2560_PSCSR2,      0x00020002 },
        { RT2560_PSCSR3,      0x00000002 },
        { RT2560_TIMECSR,     0x00003f21 },
        { RT2560_CSR9,        0x00000780 },
        { RT2560_CSR11,       0x07041483 },
        { RT2560_CNT3,        0x00000000 },
        { RT2560_TXCSR1,      0x07614562 },
        { RT2560_ARSP_PLCP_0, 0x8c8d8b8a },
        { RT2560_ACKPCTCSR,   0x7038140a },
        { RT2560_ARTCSR1,     0x1d21252d },
        { RT2560_ARTCSR2,     0x1919191d },
        { RT2560_RXCSR0,      0xffffffff },
        { RT2560_RXCSR3,      0xb3aab3af },
        { RT2560_PCICSR,      0x000003b8 },
        { RT2560_PWRCSR0,     0x3f3b3100 },
        { RT2560_GPIOCSR,     0x0000ff00 },
        { RT2560_TESTCSR,     0x000000f0 },
        { RT2560_PWRCSR1,     0x000001ff },
        { RT2560_MACCSR0,     0x00213223 },
        { RT2560_MACCSR1,     0x00235518 },
        { RT2560_RLPWCSR,     0x00000040 },
        { RT2560_RALINKCSR,   0x9a009a11 },
        { RT2560_CSR7,        0xffffffff },
        { RT2560_BBPCSR1,     0x82188200 },
        { RT2560_TXACKCSR0,   0x00000020 },
        { RT2560_SECCSR3,     0x0000e78f }
};

/*
 * Default values for BBP registers; values taken from the reference driver.
 */
static const struct {
        uint8_t reg;
        uint8_t val;
} rt2560_def_bbp[] = {
        {  3, 0x02 },
        {  4, 0x19 },
        { 14, 0x1c },
        { 15, 0x30 },
        { 16, 0xac },
        { 17, 0x48 },
        { 18, 0x18 },
        { 19, 0xff },
        { 20, 0x1e },
        { 21, 0x08 },
        { 22, 0x08 },
        { 23, 0x08 },
        { 24, 0x80 },
        { 25, 0x50 },
        { 26, 0x08 },
        { 27, 0x23 },
        { 30, 0x10 },
        { 31, 0x2b },
        { 32, 0xb9 },
        { 34, 0x12 },
        { 35, 0x50 },
        { 39, 0xc4 },
        { 40, 0x02 },
        { 41, 0x60 },
        { 53, 0x10 },
        { 54, 0x18 },
        { 56, 0x08 },
        { 57, 0x10 },
        { 58, 0x08 },
        { 61, 0x60 },
        { 62, 0x10 },
        { 75, 0xff }
};

/*
 * Default values for RF register R2 indexed by channel numbers; values taken
 * from the reference driver.
 */
static const uint32_t rt2560_rf2522_r2[] = {
        0x307f6, 0x307fb, 0x30800, 0x30805, 0x3080a, 0x3080f, 0x30814,
        0x30819, 0x3081e, 0x30823, 0x30828, 0x3082d, 0x30832, 0x3083e
};

static const uint32_t rt2560_rf2523_r2[] = {
        0x00327, 0x00328, 0x00329, 0x0032a, 0x0032b, 0x0032c, 0x0032d,
        0x0032e, 0x0032f, 0x00340, 0x00341, 0x00342, 0x00343, 0x00346
};

static const uint32_t rt2560_rf2524_r2[] = {
        0x00327, 0x00328, 0x00329, 0x0032a, 0x0032b, 0x0032c, 0x0032d,
        0x0032e, 0x0032f, 0x00340, 0x00341, 0x00342, 0x00343, 0x00346
};

static const uint32_t rt2560_rf2525_r2[] = {
        0x20327, 0x20328, 0x20329, 0x2032a, 0x2032b, 0x2032c, 0x2032d,
        0x2032e, 0x2032f, 0x20340, 0x20341, 0x20342, 0x20343, 0x20346
};

static const uint32_t rt2560_rf2525_hi_r2[] = {
        0x2032f, 0x20340, 0x20341, 0x20342, 0x20343, 0x20344, 0x20345,
        0x20346, 0x20347, 0x20348, 0x20349, 0x2034a, 0x2034b, 0x2034e
};

static const uint32_t rt2560_rf2525e_r2[] = {
        0x2044d, 0x2044e, 0x2044f, 0x20460, 0x20461, 0x20462, 0x20463,
        0x20464, 0x20465, 0x20466, 0x20467, 0x20468, 0x20469, 0x2046b
};

static const uint32_t rt2560_rf2526_hi_r2[] = {
        0x0022a, 0x0022b, 0x0022b, 0x0022c, 0x0022c, 0x0022d, 0x0022d,
        0x0022e, 0x0022e, 0x0022f, 0x0022d, 0x00240, 0x00240, 0x00241
};

static const uint32_t rt2560_rf2526_r2[] = {
        0x00226, 0x00227, 0x00227, 0x00228, 0x00228, 0x00229, 0x00229,
        0x0022a, 0x0022a, 0x0022b, 0x0022b, 0x0022c, 0x0022c, 0x0022d
};

/*
 * For dual-band RF, RF registers R1 and R4 also depend on channel number;
 * values taken from the reference driver.
 */
static const struct {
        uint8_t         chan;
        uint32_t        r1;
        uint32_t        r2;
        uint32_t        r4;
} rt2560_rf5222[] = {
        {   1, 0x08808, 0x0044d, 0x00282 },
        {   2, 0x08808, 0x0044e, 0x00282 },
        {   3, 0x08808, 0x0044f, 0x00282 },
        {   4, 0x08808, 0x00460, 0x00282 },
        {   5, 0x08808, 0x00461, 0x00282 },
        {   6, 0x08808, 0x00462, 0x00282 },
        {   7, 0x08808, 0x00463, 0x00282 },
        {   8, 0x08808, 0x00464, 0x00282 },
        {   9, 0x08808, 0x00465, 0x00282 },
        {  10, 0x08808, 0x00466, 0x00282 },
        {  11, 0x08808, 0x00467, 0x00282 },
        {  12, 0x08808, 0x00468, 0x00282 },
        {  13, 0x08808, 0x00469, 0x00282 },
        {  14, 0x08808, 0x0046b, 0x00286 },

        {  36, 0x08804, 0x06225, 0x00287 },
        {  40, 0x08804, 0x06226, 0x00287 },
        {  44, 0x08804, 0x06227, 0x00287 },
        {  48, 0x08804, 0x06228, 0x00287 },
        {  52, 0x08804, 0x06229, 0x00287 },
        {  56, 0x08804, 0x0622a, 0x00287 },
        {  60, 0x08804, 0x0622b, 0x00287 },
        {  64, 0x08804, 0x0622c, 0x00287 },

        { 100, 0x08804, 0x02200, 0x00283 },
        { 104, 0x08804, 0x02201, 0x00283 },
        { 108, 0x08804, 0x02202, 0x00283 },
        { 112, 0x08804, 0x02203, 0x00283 },
        { 116, 0x08804, 0x02204, 0x00283 },
        { 120, 0x08804, 0x02205, 0x00283 },
        { 124, 0x08804, 0x02206, 0x00283 },
        { 128, 0x08804, 0x02207, 0x00283 },
        { 132, 0x08804, 0x02208, 0x00283 },
        { 136, 0x08804, 0x02209, 0x00283 },
        { 140, 0x08804, 0x0220a, 0x00283 },

        { 149, 0x08808, 0x02429, 0x00281 },
        { 153, 0x08808, 0x0242b, 0x00281 },
        { 157, 0x08808, 0x0242d, 0x00281 },
        { 161, 0x08808, 0x0242f, 0x00281 }
};

int
rt2560_attach(void *xsc, int id)
{
        struct rt2560_softc *sc = xsc;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = &sc->sc_if;
        int error, i;

        callout_init(&sc->scan_ch, 0);
        callout_init(&sc->rssadapt_ch, 0);

        /* retrieve RT2560 rev. no */
        sc->asic_rev = RAL_READ(sc, RT2560_CSR0);

        /* retrieve MAC address */
        rt2560_get_macaddr(sc, ic->ic_myaddr);

        aprint_normal_dev(sc->sc_dev, "802.11 address %s\n",
            ether_sprintf(ic->ic_myaddr));

        /* retrieve RF rev. no and various other things from EEPROM */
        rt2560_read_eeprom(sc);

        aprint_normal_dev(sc->sc_dev, "MAC/BBP RT2560 (rev 0x%02x), RF %s\n",
            sc->asic_rev, rt2560_get_rf(sc->rf_rev));

        sc->sc_soft_ih = softint_establish(SOFTINT_NET, rt2560_softintr, sc);
        if (sc->sc_soft_ih == NULL) {
                aprint_error_dev(sc->sc_dev, "could not establish softint\n)");
                goto fail0;
        }

        /*
         * Allocate Tx and Rx rings.
         */
        error = rt2560_alloc_tx_ring(sc, &sc->txq, RT2560_TX_RING_COUNT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate Tx ring\n)");
                goto fail1;
        }

        error = rt2560_alloc_tx_ring(sc, &sc->atimq, RT2560_ATIM_RING_COUNT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate ATIM ring\n");
                goto fail2;
        }

        error = rt2560_alloc_tx_ring(sc, &sc->prioq, RT2560_PRIO_RING_COUNT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate Prio ring\n");
                goto fail3;
        }

        error = rt2560_alloc_tx_ring(sc, &sc->bcnq, RT2560_BEACON_RING_COUNT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate Beacon ring\n");
                goto fail4;
        }

        error = rt2560_alloc_rx_ring(sc, &sc->rxq, RT2560_RX_RING_COUNT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate Rx ring\n");
                goto fail5;
        }

        ifp->if_softc = sc;
        ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
        ifp->if_init = rt2560_init;
        ifp->if_stop = rt2560_stop;
        ifp->if_ioctl = rt2560_ioctl;
        ifp->if_start = rt2560_start;
        ifp->if_watchdog = rt2560_watchdog;
        IFQ_SET_READY(&ifp->if_snd);
        memcpy(ifp->if_xname, device_xname(sc->sc_dev), IFNAMSIZ);

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

        /* set device capabilities */
        ic->ic_caps =
            IEEE80211_C_IBSS |          /* IBSS mode supported */
            IEEE80211_C_MONITOR |       /* monitor mode supported */
            IEEE80211_C_HOSTAP |        /* HostAp mode supported */
            IEEE80211_C_TXPMGT |        /* tx power management */
            IEEE80211_C_SHPREAMBLE |    /* short preamble supported */
            IEEE80211_C_SHSLOT |        /* short slot time supported */
            IEEE80211_C_WPA;            /* 802.11i */

        if (sc->rf_rev == RT2560_RF_5222) {
                /* set supported .11a rates */
                ic->ic_sup_rates[IEEE80211_MODE_11A] = ieee80211_std_rateset_11a;

                /* set supported .11a channels */
                for (i = 36; i <= 64; i += 4) {
                        ic->ic_channels[i].ic_freq =
                            ieee80211_ieee2mhz(i, IEEE80211_CHAN_5GHZ);
                        ic->ic_channels[i].ic_flags = IEEE80211_CHAN_A;
                }
                for (i = 100; i <= 140; i += 4) {
                        ic->ic_channels[i].ic_freq =
                            ieee80211_ieee2mhz(i, IEEE80211_CHAN_5GHZ);
                        ic->ic_channels[i].ic_flags = IEEE80211_CHAN_A;
                }
                for (i = 149; i <= 161; i += 4) {
                        ic->ic_channels[i].ic_freq =
                            ieee80211_ieee2mhz(i, IEEE80211_CHAN_5GHZ);
                        ic->ic_channels[i].ic_flags = IEEE80211_CHAN_A;
                }
        }

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

        /* set supported .11b and .11g channels (1 through 14) */
        for (i = 1; i <= 14; i++) {
                ic->ic_channels[i].ic_freq =
                    ieee80211_ieee2mhz(i, IEEE80211_CHAN_2GHZ);
                ic->ic_channels[i].ic_flags =
                    IEEE80211_CHAN_CCK | IEEE80211_CHAN_OFDM |
                    IEEE80211_CHAN_DYN | IEEE80211_CHAN_2GHZ;
        }

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

        ic->ic_node_alloc = rt2560_node_alloc;
        ic->ic_updateslot = rt2560_update_slot;
        ic->ic_reset = rt2560_reset;

        /* override state transition machine */
        sc->sc_newstate = ic->ic_newstate;
        ic->ic_newstate = rt2560_newstate;
        ieee80211_media_init(ic, rt2560_media_change, ieee80211_media_status);

        bpf_attach2(ifp, DLT_IEEE802_11_RADIO,
            sizeof(struct ieee80211_frame) + 64, &sc->sc_drvbpf);

        sc->sc_rxtap_len = sizeof sc->sc_rxtapu;
        sc->sc_rxtap.wr_ihdr.it_len = htole16(sc->sc_rxtap_len);
        sc->sc_rxtap.wr_ihdr.it_present = htole32(RT2560_RX_RADIOTAP_PRESENT);

        sc->sc_txtap_len = sizeof sc->sc_txtapu;
        sc->sc_txtap.wt_ihdr.it_len = htole16(sc->sc_txtap_len);
        sc->sc_txtap.wt_ihdr.it_present = htole32(RT2560_TX_RADIOTAP_PRESENT);


        sc->dwelltime = 200;

        ieee80211_announce(ic);

        if (pmf_device_register(sc->sc_dev, NULL, NULL))
                pmf_class_network_register(sc->sc_dev, ifp);
        else
                aprint_error_dev(sc->sc_dev,
                    "couldn't establish power handler\n");

        return 0;

fail5:  rt2560_free_tx_ring(sc, &sc->bcnq);
fail4:  rt2560_free_tx_ring(sc, &sc->prioq);
fail3:  rt2560_free_tx_ring(sc, &sc->atimq);
fail2:  rt2560_free_tx_ring(sc, &sc->txq);
fail1:  softint_disestablish(sc->sc_soft_ih);
        sc->sc_soft_ih = NULL;
fail0:  return ENXIO;
}


int
rt2560_detach(void *xsc)
{
        struct rt2560_softc *sc = xsc;
        struct ifnet *ifp = &sc->sc_if;

        callout_stop(&sc->scan_ch);
        callout_stop(&sc->rssadapt_ch);

        pmf_device_deregister(sc->sc_dev);

        rt2560_stop(ifp, 1);

        ieee80211_ifdetach(&sc->sc_ic); /* free all nodes */
        if_detach(ifp);

        rt2560_free_tx_ring(sc, &sc->txq);
        rt2560_free_tx_ring(sc, &sc->atimq);
        rt2560_free_tx_ring(sc, &sc->prioq);
        rt2560_free_tx_ring(sc, &sc->bcnq);
        rt2560_free_rx_ring(sc, &sc->rxq);

        if (sc->sc_soft_ih != NULL) {
                softint_disestablish(sc->sc_soft_ih);
                sc->sc_soft_ih = NULL;
        }

        return 0;
}

int
rt2560_alloc_tx_ring(struct rt2560_softc *sc, struct rt2560_tx_ring *ring,
    int count)
{
        int i, nsegs, error;

        ring->count = count;
        ring->queued = 0;
        ring->cur = ring->next = 0;
        ring->cur_encrypt = ring->next_encrypt = 0;

        error = bus_dmamap_create(sc->sc_dmat, count * RT2560_TX_DESC_SIZE, 1,
            count * RT2560_TX_DESC_SIZE, 0, BUS_DMA_NOWAIT, &ring->map);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not create desc DMA map\n");
                goto fail;
        }

        error = bus_dmamem_alloc(sc->sc_dmat, count * RT2560_TX_DESC_SIZE,
            PAGE_SIZE, 0, &ring->seg, 1, &nsegs, BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate DMA memory\n");
                goto fail;
        }

        error = bus_dmamem_map(sc->sc_dmat, &ring->seg, nsegs,
            count * RT2560_TX_DESC_SIZE, (void **)&ring->desc,
            BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not map desc DMA memory\n");
                goto fail;
        }

        error = bus_dmamap_load(sc->sc_dmat, ring->map, ring->desc,
            count * RT2560_TX_DESC_SIZE, NULL, BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not load desc DMA map\n");
                goto fail;
        }

        memset(ring->desc, 0, count * RT2560_TX_DESC_SIZE);
        ring->physaddr = ring->map->dm_segs->ds_addr;

        ring->data = malloc(count * sizeof (struct rt2560_tx_data), M_DEVBUF,
            M_WAITOK | M_ZERO);

        for (i = 0; i < count; i++) {
                error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
                    RT2560_MAX_SCATTER, MCLBYTES, 0, BUS_DMA_NOWAIT,
                    &ring->data[i].map);
                if (error != 0) {
                        aprint_error_dev(sc->sc_dev, "could not create DMA map\n");
                        goto fail;
                }
        }

        return 0;

fail:   rt2560_free_tx_ring(sc, ring);
        return error;
}

void
rt2560_reset_tx_ring(struct rt2560_softc *sc, struct rt2560_tx_ring *ring)
{
        struct rt2560_tx_desc *desc;
        struct rt2560_tx_data *data;
        int i;

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

                if (data->m != NULL) {
                        bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                            data->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
                        bus_dmamap_unload(sc->sc_dmat, data->map);
                        m_freem(data->m);
                        data->m = NULL;
                }

                if (data->ni != NULL) {
                        ieee80211_free_node(data->ni);
                        data->ni = NULL;
                }

                desc->flags = 0;
        }

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

        ring->queued = 0;
        ring->cur = ring->next = 0;
        ring->cur_encrypt = ring->next_encrypt = 0;
}

void
rt2560_free_tx_ring(struct rt2560_softc *sc, struct rt2560_tx_ring *ring)
{
        struct rt2560_tx_data *data;
        int i;

        if (ring->desc != NULL) {
                bus_dmamap_sync(sc->sc_dmat, ring->map, 0,
                    ring->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(sc->sc_dmat, ring->map);
                bus_dmamem_unmap(sc->sc_dmat, (void *)ring->desc,
                    ring->count * RT2560_TX_DESC_SIZE);
                bus_dmamem_free(sc->sc_dmat, &ring->seg, 1);
        }

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

                        if (data->m != NULL) {
                                bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                                    data->map->dm_mapsize,
                                    BUS_DMASYNC_POSTWRITE);
                                bus_dmamap_unload(sc->sc_dmat, data->map);
                                m_freem(data->m);
                        }

                        if (data->ni != NULL)
                                ieee80211_free_node(data->ni);


                        if (data->map != NULL)
                                bus_dmamap_destroy(sc->sc_dmat, data->map);
                }
                free(ring->data, M_DEVBUF);
        }
}

int
rt2560_alloc_rx_ring(struct rt2560_softc *sc, struct rt2560_rx_ring *ring,
    int count)
{
        struct rt2560_rx_desc *desc;
        struct rt2560_rx_data *data;
        int i, nsegs, error;

        ring->count = count;
        ring->cur = ring->next = 0;
        ring->cur_decrypt = 0;

        error = bus_dmamap_create(sc->sc_dmat, count * RT2560_RX_DESC_SIZE, 1,
            count * RT2560_RX_DESC_SIZE, 0, BUS_DMA_NOWAIT, &ring->map);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not create desc DMA map\n");
                goto fail;
        }

        error = bus_dmamem_alloc(sc->sc_dmat, count * RT2560_RX_DESC_SIZE,
            PAGE_SIZE, 0, &ring->seg, 1, &nsegs, BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate DMA memory\n");
                goto fail;
        }

        error = bus_dmamem_map(sc->sc_dmat, &ring->seg, nsegs,
            count * RT2560_RX_DESC_SIZE, (void **)&ring->desc,
            BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not map desc DMA memory\n");
                goto fail;
        }

        error = bus_dmamap_load(sc->sc_dmat, ring->map, ring->desc,
            count * RT2560_RX_DESC_SIZE, NULL, BUS_DMA_NOWAIT);
        if (error != 0) {
                aprint_error_dev(sc->sc_dev, "could not load desc DMA map\n");
                goto fail;
        }

        memset(ring->desc, 0, count * RT2560_RX_DESC_SIZE);
        ring->physaddr = ring->map->dm_segs->ds_addr;

        ring->data = malloc(count * sizeof (struct rt2560_rx_data), M_DEVBUF,
            M_WAITOK | M_ZERO);

        /*
         * Pre-allocate Rx buffers and populate Rx ring.
         */
        for (i = 0; i < count; i++) {
                desc = &sc->rxq.desc[i];
                data = &sc->rxq.data[i];

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

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

                MCLGET(data->m, M_DONTWAIT);
                if (!(data->m->m_flags & M_EXT)) {
                        aprint_error_dev(sc->sc_dev, "could not allocate rx mbuf cluster\n");
                        error = ENOMEM;
                        goto fail;
                }

                error = bus_dmamap_load(sc->sc_dmat, data->map,
                    mtod(data->m, void *), MCLBYTES, NULL, BUS_DMA_NOWAIT);
                if (error != 0) {
                        aprint_error_dev(sc->sc_dev, "could not load rx buf DMA map");
                        goto fail;
                }

                desc->flags = htole32(RT2560_RX_BUSY);
                desc->physaddr = htole32(data->map->dm_segs->ds_addr);
        }

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

        return 0;

fail:   rt2560_free_rx_ring(sc, ring);
        return error;
}

void
rt2560_reset_rx_ring(struct rt2560_softc *sc, struct rt2560_rx_ring *ring)
{
        int i;

        for (i = 0; i < ring->count; i++) {
                ring->desc[i].flags = htole32(RT2560_RX_BUSY);
                ring->data[i].drop = 0;
        }

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

        ring->cur = ring->next = 0;
        ring->cur_decrypt = 0;
}

void
rt2560_free_rx_ring(struct rt2560_softc *sc, struct rt2560_rx_ring *ring)
{
        struct rt2560_rx_data *data;
        int i;

        if (ring->desc != NULL) {
                bus_dmamap_sync(sc->sc_dmat, ring->map, 0,
                    ring->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(sc->sc_dmat, ring->map);
                bus_dmamem_unmap(sc->sc_dmat, (void *)ring->desc,
                    ring->count * RT2560_RX_DESC_SIZE);
                bus_dmamem_free(sc->sc_dmat, &ring->seg, 1);
        }

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

                        if (data->m != NULL) {
                                bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                                    data->map->dm_mapsize,
                                    BUS_DMASYNC_POSTREAD);
                                bus_dmamap_unload(sc->sc_dmat, data->map);
                                m_freem(data->m);
                        }

                        if (data->map != NULL)
                                bus_dmamap_destroy(sc->sc_dmat, data->map);
                }
                free(ring->data, M_DEVBUF);
        }
}

struct ieee80211_node *
rt2560_node_alloc(struct ieee80211_node_table *nt)
{
        struct rt2560_node *rn;

        rn = malloc(sizeof (struct rt2560_node), M_80211_NODE,
            M_NOWAIT | M_ZERO);

        return (rn != NULL) ? &rn->ni : NULL;
}

int
rt2560_media_change(struct ifnet *ifp)
{
        int error;

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

        if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == (IFF_UP | IFF_RUNNING))
                rt2560_init(ifp);

        return 0;
}

/*
 * This function is called periodically (every 200ms) during scanning to
 * switch from one channel to another.
 */
void
rt2560_next_scan(void *arg)
{
        struct rt2560_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;
        int s;

        s = splnet();
        if (ic->ic_state == IEEE80211_S_SCAN)
                ieee80211_next_scan(ic);
        splx(s);
}

/*
 * This function is called for each neighbor node.
 */
void
rt2560_iter_func(void *arg, struct ieee80211_node *ni)
{
        struct rt2560_node *rn = (struct rt2560_node *)ni;

        ieee80211_rssadapt_updatestats(&rn->rssadapt);
}

/*
 * This function is called periodically (every 100ms) in RUN state to update
 * the rate adaptation statistics.
 */
void
rt2560_update_rssadapt(void *arg)
{
        struct rt2560_softc *sc = arg;
        struct ieee80211com *ic = &sc->sc_ic;
        int s;

        s = splnet();
        ieee80211_iterate_nodes(&ic->ic_sta, rt2560_iter_func, arg);

        callout_reset(&sc->rssadapt_ch, hz / 10, rt2560_update_rssadapt, sc);
        splx(s);
}

int
rt2560_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
{
        struct rt2560_softc *sc = ic->ic_ifp->if_softc;
        enum ieee80211_state ostate;
        struct ieee80211_node *ni;
        struct mbuf *m;
        int error = 0;

        ostate = ic->ic_state;
        callout_stop(&sc->scan_ch);

        switch (nstate) {
        case IEEE80211_S_INIT:
                callout_stop(&sc->rssadapt_ch);

                if (ostate == IEEE80211_S_RUN) {
                        /* abort TSF synchronization */
                        RAL_WRITE(sc, RT2560_CSR14, 0);

                        /* turn association led off */
                        rt2560_update_led(sc, 0, 0);
                }
                break;

        case IEEE80211_S_SCAN:
                rt2560_set_chan(sc, ic->ic_curchan);
                callout_reset(&sc->scan_ch, (sc->dwelltime * hz) / 1000,
                    rt2560_next_scan, sc);
                break;

        case IEEE80211_S_AUTH:
                rt2560_set_chan(sc, ic->ic_curchan);
                break;

        case IEEE80211_S_ASSOC:
                rt2560_set_chan(sc, ic->ic_curchan);
                break;

        case IEEE80211_S_RUN:
                rt2560_set_chan(sc, ic->ic_curchan);

                ni = ic->ic_bss;

                if (ic->ic_opmode != IEEE80211_M_MONITOR) {
                        rt2560_update_plcp(sc);
                        rt2560_set_basicrates(sc);
                        rt2560_set_bssid(sc, ni->ni_bssid);
                }

                if (ic->ic_opmode == IEEE80211_M_HOSTAP ||
                    ic->ic_opmode == IEEE80211_M_IBSS) {
                        m = ieee80211_beacon_alloc(ic, ni, &sc->sc_bo);
                        if (m == NULL) {
                                aprint_error_dev(sc->sc_dev, "could not allocate beacon\n");
                                error = ENOBUFS;
                                break;
                        }

                        ieee80211_ref_node(ni);
                        error = rt2560_tx_bcn(sc, m, ni);
                        if (error != 0)
                                break;
                }

                /* turn association led on */
                rt2560_update_led(sc, 1, 0);

                if (ic->ic_opmode != IEEE80211_M_MONITOR) {
                        callout_reset(&sc->rssadapt_ch, hz / 10,
                            rt2560_update_rssadapt, sc);
                        rt2560_enable_tsf_sync(sc);
                }
                break;
        }

        return (error != 0) ? error : sc->sc_newstate(ic, nstate, arg);
}

/*
 * Read 16 bits at address 'addr' from the serial EEPROM (either 93C46 or
 * 93C66).
 */
uint16_t
rt2560_eeprom_read(struct rt2560_softc *sc, uint8_t addr)
{
        uint32_t tmp;
        uint16_t val;
        int n;

        /* clock C once before the first command */
        RT2560_EEPROM_CTL(sc, 0);

        RT2560_EEPROM_CTL(sc, RT2560_S);
        RT2560_EEPROM_CTL(sc, RT2560_S | RT2560_C);
        RT2560_EEPROM_CTL(sc, RT2560_S);

        /* write start bit (1) */
        RT2560_EEPROM_CTL(sc, RT2560_S | RT2560_D);
        RT2560_EEPROM_CTL(sc, RT2560_S | RT2560_D | RT2560_C);

        /* write READ opcode (10) */
        RT2560_EEPROM_CTL(sc, RT2560_S | RT2560_D);
        RT2560_EEPROM_CTL(sc, RT2560_S | RT2560_D | RT2560_C);
        RT2560_EEPROM_CTL(sc, RT2560_S);
        RT2560_EEPROM_CTL(sc, RT2560_S | RT2560_C);

        /* write address (A5-A0 or A7-A0) */
        n = (RAL_READ(sc, RT2560_CSR21) & RT2560_93C46) ? 5 : 7;
        for (; n >= 0; n--) {
                RT2560_EEPROM_CTL(sc, RT2560_S |
                    (((addr >> n) & 1) << RT2560_SHIFT_D));
                RT2560_EEPROM_CTL(sc, RT2560_S |
                    (((addr >> n) & 1) << RT2560_SHIFT_D) | RT2560_C);
        }

        RT2560_EEPROM_CTL(sc, RT2560_S);

        /* read data Q15-Q0 */
        val = 0;
        for (n = 15; n >= 0; n--) {
                RT2560_EEPROM_CTL(sc, RT2560_S | RT2560_C);
                tmp = RAL_READ(sc, RT2560_CSR21);
                val |= ((tmp & RT2560_Q) >> RT2560_SHIFT_Q) << n;
                RT2560_EEPROM_CTL(sc, RT2560_S);
        }

        RT2560_EEPROM_CTL(sc, 0);

        /* clear Chip Select and clock C */
        RT2560_EEPROM_CTL(sc, RT2560_S);
        RT2560_EEPROM_CTL(sc, 0);
        RT2560_EEPROM_CTL(sc, RT2560_C);

        return val;
}

/*
 * Some frames were processed by the hardware cipher engine and are ready for
 * transmission.
 */
void
rt2560_encryption_intr(struct rt2560_softc *sc)
{
        struct rt2560_tx_desc *desc;
        int hw;

        /* retrieve last descriptor index processed by cipher engine */
        hw = (RAL_READ(sc, RT2560_SECCSR1) - sc->txq.physaddr) /
            RT2560_TX_DESC_SIZE;

        for (; sc->txq.next_encrypt != hw;) {
                desc = &sc->txq.desc[sc->txq.next_encrypt];

                bus_dmamap_sync(sc->sc_dmat, sc->txq.map,
                    sc->txq.next_encrypt * RT2560_TX_DESC_SIZE,
                    RT2560_TX_DESC_SIZE, BUS_DMASYNC_POSTREAD);

                if (le32toh(desc->flags) &
                    (RT2560_TX_BUSY | RT2560_TX_CIPHER_BUSY))
                        break;

                /* for TKIP, swap eiv field to fix a bug in ASIC */
                if ((le32toh(desc->flags) & RT2560_TX_CIPHER_MASK) ==
                    RT2560_TX_CIPHER_TKIP)
                        desc->eiv = bswap32(desc->eiv);

                /* mark the frame ready for transmission */
                desc->flags |= htole32(RT2560_TX_BUSY | RT2560_TX_VALID);

                bus_dmamap_sync(sc->sc_dmat, sc->txq.map,
                    sc->txq.next_encrypt * RT2560_TX_DESC_SIZE,
                    RT2560_TX_DESC_SIZE, BUS_DMASYNC_PREWRITE);

                DPRINTFN(15, ("encryption done idx=%u\n",
                    sc->txq.next_encrypt));

                sc->txq.next_encrypt =
                    (sc->txq.next_encrypt + 1) % RT2560_TX_RING_COUNT;
        }

        /* kick Tx */
        RAL_WRITE(sc, RT2560_TXCSR0, RT2560_KICK_TX);
}

void
rt2560_tx_intr(struct rt2560_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct rt2560_tx_desc *desc;
        struct rt2560_tx_data *data;
        struct rt2560_node *rn;
        int s;

        s = splnet();

        for (;;) {
                desc = &sc->txq.desc[sc->txq.next];
                data = &sc->txq.data[sc->txq.next];

                bus_dmamap_sync(sc->sc_dmat, sc->txq.map,
                    sc->txq.next * RT2560_TX_DESC_SIZE, RT2560_TX_DESC_SIZE,
                    BUS_DMASYNC_POSTREAD);

                if ((le32toh(desc->flags) & RT2560_TX_BUSY) ||
                    (le32toh(desc->flags) & RT2560_TX_CIPHER_BUSY) ||
                    !(le32toh(desc->flags) & RT2560_TX_VALID))
                        break;

                rn = (struct rt2560_node *)data->ni;

                switch (le32toh(desc->flags) & RT2560_TX_RESULT_MASK) {
                case RT2560_TX_SUCCESS:
                        DPRINTFN(10, ("data frame sent successfully\n"));
                        if (data->id.id_node != NULL) {
                                ieee80211_rssadapt_raise_rate(ic,
                                    &rn->rssadapt, &data->id);
                        }
                        if_statinc(ifp, if_opackets);
                        break;

                case RT2560_TX_SUCCESS_RETRY:
                        DPRINTFN(9, ("data frame sent after %u retries\n",
                            (le32toh(desc->flags) >> 5) & 0x7));
                        if_statinc(ifp, if_opackets);
                        break;

                case RT2560_TX_FAIL_RETRY:
                        DPRINTFN(9, ("sending data frame failed (too much "
                            "retries)\n"));
                        if (data->id.id_node != NULL) {
                                ieee80211_rssadapt_lower_rate(ic, data->ni,
                                    &rn->rssadapt, &data->id);
                        }
                        if_statinc(ifp, if_oerrors);
                        break;

                case RT2560_TX_FAIL_INVALID:
                case RT2560_TX_FAIL_OTHER:
                default:
                        aprint_error_dev(sc->sc_dev,
                            "sending data frame failed 0x%08x\n",
                            le32toh(desc->flags));
                        if_statinc(ifp, if_oerrors);
                }

                bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                    data->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(sc->sc_dmat, data->map);
                m_freem(data->m);
                data->m = NULL;
                ieee80211_free_node(data->ni);
                data->ni = NULL;

                /* descriptor is no longer valid */
                desc->flags &= ~htole32(RT2560_TX_VALID);

                bus_dmamap_sync(sc->sc_dmat, sc->txq.map,
                    sc->txq.next * RT2560_TX_DESC_SIZE, RT2560_TX_DESC_SIZE,
                    BUS_DMASYNC_PREWRITE);

                DPRINTFN(15, ("tx done idx=%u\n", sc->txq.next));

                sc->txq.queued--;
                sc->txq.next = (sc->txq.next + 1) % RT2560_TX_RING_COUNT;
        }

        sc->sc_tx_timer = 0;
        ifp->if_flags &= ~IFF_OACTIVE;
        rt2560_start(ifp); /* in softint */

        splx(s);
}

void
rt2560_prio_intr(struct rt2560_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct rt2560_tx_desc *desc;
        struct rt2560_tx_data *data;
        int s;

        s = splnet();

        for (;;) {
                desc = &sc->prioq.desc[sc->prioq.next];
                data = &sc->prioq.data[sc->prioq.next];

                bus_dmamap_sync(sc->sc_dmat, sc->prioq.map,
                    sc->prioq.next * RT2560_TX_DESC_SIZE, RT2560_TX_DESC_SIZE,
                    BUS_DMASYNC_POSTREAD);

                if ((le32toh(desc->flags) & RT2560_TX_BUSY) ||
                    !(le32toh(desc->flags) & RT2560_TX_VALID))
                        break;

                switch (le32toh(desc->flags) & RT2560_TX_RESULT_MASK) {
                case RT2560_TX_SUCCESS:
                        DPRINTFN(10, ("mgt frame sent successfully\n"));
                        break;

                case RT2560_TX_SUCCESS_RETRY:
                        DPRINTFN(9, ("mgt frame sent after %u retries\n",
                            (le32toh(desc->flags) >> 5) & 0x7));
                        break;

                case RT2560_TX_FAIL_RETRY:
                        DPRINTFN(9, ("sending mgt frame failed (too much "
                            "retries)\n"));
                        break;

                case RT2560_TX_FAIL_INVALID:
                case RT2560_TX_FAIL_OTHER:
                default:
                        aprint_error_dev(sc->sc_dev, "sending mgt frame failed 0x%08x\n",
                            le32toh(desc->flags));
                }

                bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                    data->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
                bus_dmamap_unload(sc->sc_dmat, data->map);
                m_freem(data->m);
                data->m = NULL;
                ieee80211_free_node(data->ni);
                data->ni = NULL;

                /* descriptor is no longer valid */
                desc->flags &= ~htole32(RT2560_TX_VALID);

                bus_dmamap_sync(sc->sc_dmat, sc->prioq.map,
                    sc->prioq.next * RT2560_TX_DESC_SIZE, RT2560_TX_DESC_SIZE,
                    BUS_DMASYNC_PREWRITE);

                DPRINTFN(15, ("prio done idx=%u\n", sc->prioq.next));

                sc->prioq.queued--;
                sc->prioq.next = (sc->prioq.next + 1) % RT2560_PRIO_RING_COUNT;
        }

        sc->sc_tx_timer = 0;
        ifp->if_flags &= ~IFF_OACTIVE;
        rt2560_start(ifp); /* in softint */

        splx(s);
}

/*
 * Some frames were processed by the hardware cipher engine and are ready for
 * transmission to the IEEE802.11 layer.
 */
void
rt2560_decryption_intr(struct rt2560_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct rt2560_rx_desc *desc;
        struct rt2560_rx_data *data;
        struct rt2560_node *rn;
        struct ieee80211_frame *wh;
        struct ieee80211_node *ni;
        struct mbuf *mnew, *m;
        int hw, error, s;

        /* retrieve last descriptor index processed by cipher engine */
        hw = (RAL_READ(sc, RT2560_SECCSR0) - sc->rxq.physaddr) /
            RT2560_RX_DESC_SIZE;

        for (; sc->rxq.cur_decrypt != hw;) {
                desc = &sc->rxq.desc[sc->rxq.cur_decrypt];
                data = &sc->rxq.data[sc->rxq.cur_decrypt];

                bus_dmamap_sync(sc->sc_dmat, sc->rxq.map,
                    sc->rxq.cur_decrypt * RT2560_TX_DESC_SIZE,
                    RT2560_TX_DESC_SIZE, BUS_DMASYNC_POSTREAD);

                if (le32toh(desc->flags) &
                    (RT2560_RX_BUSY | RT2560_RX_CIPHER_BUSY))
                        break;

                if (data->drop) {
                        if_statinc(ifp, if_ierrors);
                        goto skip;
                }

                if ((le32toh(desc->flags) & RT2560_RX_CIPHER_MASK) != 0 &&
                    (le32toh(desc->flags) & RT2560_RX_ICV_ERROR)) {
                        if_statinc(ifp, if_ierrors);
                        goto skip;
                }

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

                MCLGET(mnew, M_DONTWAIT);
                if (!(mnew->m_flags & M_EXT)) {
                        m_freem(mnew);
                        if_statinc(ifp, if_ierrors);
                        goto skip;
                }

                bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                    data->map->dm_mapsize, BUS_DMASYNC_POSTREAD);
                bus_dmamap_unload(sc->sc_dmat, data->map);

                error = bus_dmamap_load(sc->sc_dmat, data->map,
                    mtod(mnew, void *), MCLBYTES, NULL, BUS_DMA_NOWAIT);
                if (error != 0) {
                        m_freem(mnew);

                        /* try to reload the old mbuf */
                        error = bus_dmamap_load(sc->sc_dmat, data->map,
                            mtod(data->m, void *), MCLBYTES, NULL,
                            BUS_DMA_NOWAIT);
                        if (error != 0) {
                                /* very unlikely that it will fail... */
                                panic("%s: could not load old rx mbuf",
                                    device_xname(sc->sc_dev));
                        }
                        /* physical address may have changed */
                        desc->physaddr = htole32(data->map->dm_segs->ds_addr);
                        if_statinc(ifp, if_ierrors);
                        goto skip;
                }

                /*
                 * New mbuf successfully loaded, update Rx ring and continue
                 * processing.
                 */
                m = data->m;
                data->m = mnew;
                desc->physaddr = htole32(data->map->dm_segs->ds_addr);

                /* finalize mbuf */
                m_set_rcvif(m, ifp);
                m->m_pkthdr.len = m->m_len =
                    (le32toh(desc->flags) >> 16) & 0xfff;

                s = splnet();

                if (sc->sc_drvbpf != NULL) {
                        struct rt2560_rx_radiotap_header *tap = &sc->sc_rxtap;
                        uint32_t tsf_lo, tsf_hi;

                        /* get timestamp (low and high 32 bits) */
                        tsf_hi = RAL_READ(sc, RT2560_CSR17);
                        tsf_lo = RAL_READ(sc, RT2560_CSR16);

                        tap->wr_tsf =
                            htole64(((uint64_t)tsf_hi << 32) | tsf_lo);
                        tap->wr_flags = 0;
                        tap->wr_rate = rt2560_rxrate(desc);
                        tap->wr_chan_freq = htole16(ic->ic_ibss_chan->ic_freq);
                        tap->wr_chan_flags =
                            htole16(ic->ic_ibss_chan->ic_flags);
                        tap->wr_antenna = sc->rx_ant;
                        tap->wr_antsignal = desc->rssi;

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

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

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

                /* give rssi to the rate adaptation algorithm */
                rn = (struct rt2560_node *)ni;
                ieee80211_rssadapt_input(ic, ni, &rn->rssadapt, desc->rssi);

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

                splx(s);

skip:           desc->flags = htole32(RT2560_RX_BUSY);

                bus_dmamap_sync(sc->sc_dmat, sc->rxq.map,
                    sc->rxq.cur_decrypt * RT2560_TX_DESC_SIZE,
                    RT2560_TX_DESC_SIZE, BUS_DMASYNC_PREWRITE);

                DPRINTFN(15, ("decryption done idx=%u\n", sc->rxq.cur_decrypt));

                sc->rxq.cur_decrypt =
                    (sc->rxq.cur_decrypt + 1) % RT2560_RX_RING_COUNT;
        }

        /*
         * In HostAP mode, ieee80211_input() will enqueue packets in if_snd
         * without calling if_start().
         */
        s = splnet();
        if (!IFQ_IS_EMPTY(&ifp->if_snd) && !(ifp->if_flags & IFF_OACTIVE))
                rt2560_start(ifp);
        splx(s);
}

/*
 * Some frames were received. Pass them to the hardware cipher engine before
 * sending them to the 802.11 layer.
 */
void
rt2560_rx_intr(struct rt2560_softc *sc)
{
        struct rt2560_rx_desc *desc;
        struct rt2560_rx_data *data;

        for (;;) {
                desc = &sc->rxq.desc[sc->rxq.cur];
                data = &sc->rxq.data[sc->rxq.cur];

                bus_dmamap_sync(sc->sc_dmat, sc->rxq.map,
                    sc->rxq.cur * RT2560_RX_DESC_SIZE, RT2560_RX_DESC_SIZE,
                    BUS_DMASYNC_POSTREAD);

                if (le32toh(desc->flags) &
                    (RT2560_RX_BUSY | RT2560_RX_CIPHER_BUSY))
                        break;

                data->drop = 0;

                if (le32toh(desc->flags) &
                    (RT2560_RX_PHY_ERROR | RT2560_RX_CRC_ERROR)) {
                        /*
                         * This should not happen since we did not request
                         * to receive those frames when we filled RXCSR0.
                         */
                        DPRINTFN(5, ("PHY or CRC error flags 0x%08x\n",
                            le32toh(desc->flags)));
                        data->drop = 1;
                }

                if (((le32toh(desc->flags) >> 16) & 0xfff) > MCLBYTES) {
                        DPRINTFN(5, ("bad length\n"));
                        data->drop = 1;
                }

                /* mark the frame for decryption */
                desc->flags |= htole32(RT2560_RX_CIPHER_BUSY);

                bus_dmamap_sync(sc->sc_dmat, sc->rxq.map,
                    sc->rxq.cur * RT2560_RX_DESC_SIZE, RT2560_RX_DESC_SIZE,
                    BUS_DMASYNC_PREWRITE);

                DPRINTFN(15, ("rx done idx=%u\n", sc->rxq.cur));

                sc->rxq.cur = (sc->rxq.cur + 1) % RT2560_RX_RING_COUNT;
        }

        /* kick decrypt */
        RAL_WRITE(sc, RT2560_SECCSR0, RT2560_KICK_DECRYPT);
}

/*
 * This function is called periodically in IBSS mode when a new beacon must be
 * sent out.
 */
static void
rt2560_beacon_expire(struct rt2560_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct rt2560_tx_data *data;

        if (ic->ic_opmode != IEEE80211_M_IBSS &&
            ic->ic_opmode != IEEE80211_M_HOSTAP)
                return;

        data = &sc->bcnq.data[sc->bcnq.next];

        bus_dmamap_sync(sc->sc_dmat, data->map, 0,
            data->map->dm_mapsize, BUS_DMASYNC_POSTWRITE);
        bus_dmamap_unload(sc->sc_dmat, data->map);

        ieee80211_beacon_update(ic, data->ni, &sc->sc_bo, data->m, 1);

        bpf_mtap3(ic->ic_rawbpf, data->m, BPF_D_OUT);
        rt2560_tx_bcn(sc, data->m, data->ni);

        DPRINTFN(15, ("beacon expired\n"));

        sc->bcnq.next = (sc->bcnq.next + 1) % RT2560_BEACON_RING_COUNT;
}

static void
rt2560_wakeup_expire(struct rt2560_softc *sc)
{
        DPRINTFN(15, ("wakeup expired\n"));
}

int
rt2560_intr(void *arg)
{
        struct rt2560_softc *sc = arg;
        struct ifnet *ifp = &sc->sc_if;
        uint32_t r;

        if (!device_is_active(sc->sc_dev))
                return 0;

        if ((r = RAL_READ(sc, RT2560_CSR7)) == 0)
                return 0;       /* not for us */

        /* disable interrupts */
        RAL_WRITE(sc, RT2560_CSR8, 0xffffffff);

        /* don't re-enable interrupts if we're shutting down */
        if (!(ifp->if_flags & IFF_RUNNING))
                return 0;

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

static void
rt2560_softintr(void *arg)
{
        struct rt2560_softc *sc = arg;
        struct ifnet *ifp = &sc->sc_if;
        uint32_t r;

        if (!device_is_active(sc->sc_dev) || !(ifp->if_flags & IFF_RUNNING))
                return;

        if ((r = RAL_READ(sc, RT2560_CSR7)) == 0)
                goto out;

        /* acknowledge interrupts */
        RAL_WRITE(sc, RT2560_CSR7, r);

        if (r & RT2560_BEACON_EXPIRE)
                rt2560_beacon_expire(sc);

        if (r & RT2560_WAKEUP_EXPIRE)
                rt2560_wakeup_expire(sc);

        if (r & RT2560_ENCRYPTION_DONE)
                rt2560_encryption_intr(sc);

        if (r & RT2560_TX_DONE)
                rt2560_tx_intr(sc);

        if (r & RT2560_PRIO_DONE)
                rt2560_prio_intr(sc);

        if (r & RT2560_DECRYPTION_DONE)
                rt2560_decryption_intr(sc);

        if (r & RT2560_RX_DONE)
                rt2560_rx_intr(sc);

out:
        /* re-enable interrupts */
        RAL_WRITE(sc, RT2560_CSR8, RT2560_INTR_MASK);
}

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

#define RAL_ACK_SIZE    14      /* 10 + 4(FCS) */
#define RAL_CTS_SIZE    14      /* 10 + 4(FCS) */

#define RAL_SIFS                10      /* us */

#define RT2560_RXTX_TURNAROUND  10      /* us */

/*
 * This function is only used by the Rx radiotap code. It returns the rate at
 * which a given frame was received.
 */
static uint8_t
rt2560_rxrate(struct rt2560_rx_desc *desc)
{
        if (le32toh(desc->flags) & RT2560_RX_OFDM) {
                /* reverse function of rt2560_plcp_signal */
                switch (desc->rate) {
                case 0xb:       return 12;
                case 0xf:       return 18;
                case 0xa:       return 24;
                case 0xe:       return 36;
                case 0x9:       return 48;
                case 0xd:       return 72;
                case 0x8:       return 96;
                case 0xc:       return 108;
                }
        } else {
                if (desc->rate == 10)
                        return 2;
                if (desc->rate == 20)
                        return 4;
                if (desc->rate == 55)
                        return 11;
                if (desc->rate == 110)
                        return 22;
        }
        return 2;       /* should not get there */
}

/*
 * Return the expected ack rate for a frame transmitted at rate `rate'.
 * XXX: this should depend on the destination node basic rate set.
 */
static int
rt2560_ack_rate(struct ieee80211com *ic, int rate)
{
        switch (rate) {
        /* CCK rates */
        case 2:
                return 2;
        case 4:
        case 11:
        case 22:
                return (ic->ic_curmode == IEEE80211_MODE_11B) ? 4 : rate;

        /* OFDM rates */
        case 12:
        case 18:
                return 12;
        case 24:
        case 36:
                return 24;
        case 48:
        case 72:
        case 96:
        case 108:
                return 48;
        }

        /* default to 1Mbps */
        return 2;
}

/*
 * Compute the duration (in us) needed to transmit `len' bytes at rate `rate'.
 * The function automatically determines the operating mode depending on the
 * given rate. `flags' indicates whether short preamble is in use or not.
 */
static uint16_t
rt2560_txtime(int len, int rate, uint32_t flags)
{
        uint16_t txtime;

        if (RAL_RATE_IS_OFDM(rate)) {
                /* IEEE Std 802.11a-1999, pp. 37 */
                txtime = (8 + 4 * len + 3 + rate - 1) / rate;
                txtime = 16 + 4 + 4 * txtime + 6;
        } else {
                /* IEEE Std 802.11b-1999, pp. 28 */
                txtime = (16 * len + rate - 1) / rate;
                if (rate != 2 && (flags & IEEE80211_F_SHPREAMBLE))
                        txtime +=  72 + 24;
                else
                        txtime += 144 + 48;
        }
        return txtime;
}

static uint8_t
rt2560_plcp_signal(int rate)
{
        switch (rate) {
        /* CCK rates (returned values are device-dependent) */
        case 2:         return 0x0;
        case 4:         return 0x1;
        case 11:        return 0x2;
        case 22:        return 0x3;

        /* OFDM rates (cf IEEE Std 802.11a-1999, pp. 14 Table 80) */
        case 12:        return 0xb;
        case 18:        return 0xf;
        case 24:        return 0xa;
        case 36:        return 0xe;
        case 48:        return 0x9;
        case 72:        return 0xd;
        case 96:        return 0x8;
        case 108:       return 0xc;

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

static void
rt2560_setup_tx_desc(struct rt2560_softc *sc, struct rt2560_tx_desc *desc,
    uint32_t flags, int len, int rate, int encrypt, bus_addr_t physaddr)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint16_t plcp_length;
        int remainder;

        desc->flags = htole32(flags);
        desc->flags |= htole32(len << 16);
        desc->flags |= encrypt ? htole32(RT2560_TX_CIPHER_BUSY) :
            htole32(RT2560_TX_BUSY | RT2560_TX_VALID);

        desc->physaddr = htole32(physaddr);
        desc->wme = htole16(
            RT2560_AIFSN(2) |
            RT2560_LOGCWMIN(3) |
            RT2560_LOGCWMAX(8));

        /* setup PLCP fields */
        desc->plcp_signal  = rt2560_plcp_signal(rate);
        desc->plcp_service = 4;

        len += IEEE80211_CRC_LEN;
        if (RAL_RATE_IS_OFDM(rate)) {
                desc->flags |= htole32(RT2560_TX_OFDM);

                plcp_length = len & 0xfff;
                desc->plcp_length_hi = plcp_length >> 6;
                desc->plcp_length_lo = plcp_length & 0x3f;
        } else {
                plcp_length = (16 * len + rate - 1) / rate;
                if (rate == 22) {
                        remainder = (16 * len) % 22;
                        if (remainder != 0 && remainder < 7)
                                desc->plcp_service |= RT2560_PLCP_LENGEXT;
                }
                desc->plcp_length_hi = plcp_length >> 8;
                desc->plcp_length_lo = plcp_length & 0xff;

                if (rate != 2 && (ic->ic_flags & IEEE80211_F_SHPREAMBLE))
                        desc->plcp_signal |= 0x08;
        }
}

static int
rt2560_tx_bcn(struct rt2560_softc *sc, struct mbuf *m0,
    struct ieee80211_node *ni)
{
        struct rt2560_tx_desc *desc;
        struct rt2560_tx_data *data;
        int rate, error;

        desc = &sc->bcnq.desc[sc->bcnq.cur];
        data = &sc->bcnq.data[sc->bcnq.cur];

        rate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 2;

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

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

        rt2560_setup_tx_desc(sc, desc, RT2560_TX_IFS_NEWBACKOFF |
            RT2560_TX_TIMESTAMP, m0->m_pkthdr.len, rate, 0,
            data->map->dm_segs->ds_addr);

        bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
            BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->sc_dmat, sc->bcnq.map,
            sc->bcnq.cur * RT2560_TX_DESC_SIZE, RT2560_TX_DESC_SIZE,
            BUS_DMASYNC_PREWRITE);

        return 0;
}

static int
rt2560_tx_mgt(struct rt2560_softc *sc, struct mbuf *m0,
    struct ieee80211_node *ni)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct rt2560_tx_desc *desc;
        struct rt2560_tx_data *data;
        struct ieee80211_frame *wh;
        struct ieee80211_key *k;
        uint16_t dur;
        uint32_t flags = 0;
        int rate, error;

        desc = &sc->prioq.desc[sc->prioq.cur];
        data = &sc->prioq.data[sc->prioq.cur];

        rate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 2;

        wh = mtod(m0, struct ieee80211_frame *);

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

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

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

        if (sc->sc_drvbpf != NULL) {
                struct rt2560_tx_radiotap_header *tap = &sc->sc_txtap;

                tap->wt_flags = 0;
                tap->wt_rate = rate;
                tap->wt_chan_freq = htole16(ic->ic_ibss_chan->ic_freq);
                tap->wt_chan_flags = htole16(ic->ic_ibss_chan->ic_flags);
                tap->wt_antenna = sc->tx_ant;

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

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

        wh = mtod(m0, struct ieee80211_frame *);

        if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
                flags |= RT2560_TX_ACK;

                dur = rt2560_txtime(RAL_ACK_SIZE, rate, ic->ic_flags) +
                    RAL_SIFS;
                *(uint16_t *)wh->i_dur = htole16(dur);

                /* tell hardware to add timestamp for probe responses */
                if ((wh->i_fc[0] &
                    (IEEE80211_FC0_TYPE_MASK | IEEE80211_FC0_SUBTYPE_MASK)) ==
                    (IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_RESP))
                        flags |= RT2560_TX_TIMESTAMP;
        }

        rt2560_setup_tx_desc(sc, desc, flags, m0->m_pkthdr.len, rate, 0,
            data->map->dm_segs->ds_addr);

        bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
            BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->sc_dmat, sc->prioq.map,
            sc->prioq.cur * RT2560_TX_DESC_SIZE, RT2560_TX_DESC_SIZE,
            BUS_DMASYNC_PREWRITE);

        DPRINTFN(10, ("sending mgt frame len=%u idx=%u rate=%u\n",
            m0->m_pkthdr.len, sc->prioq.cur, rate));

        /* kick prio */
        sc->prioq.queued++;
        sc->prioq.cur = (sc->prioq.cur + 1) % RT2560_PRIO_RING_COUNT;
        RAL_WRITE(sc, RT2560_TXCSR0, RT2560_KICK_PRIO);

        return 0;
}

/*
 * Build a RTS control frame.
 */
static struct mbuf *
rt2560_get_rts(struct rt2560_softc *sc, struct ieee80211_frame *wh,
    uint16_t dur)
{
        struct ieee80211_frame_rts *rts;
        struct mbuf *m;

        MGETHDR(m, M_DONTWAIT, MT_DATA);
        if (m == NULL) {
                sc->sc_ic.ic_stats.is_tx_nobuf++;
                aprint_error_dev(sc->sc_dev, "could not allocate RTS frame\n");
                return NULL;
        }

        rts = mtod(m, struct ieee80211_frame_rts *);

        rts->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_CTL |
            IEEE80211_FC0_SUBTYPE_RTS;
        rts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
        *(uint16_t *)rts->i_dur = htole16(dur);
        IEEE80211_ADDR_COPY(rts->i_ra, wh->i_addr1);
        IEEE80211_ADDR_COPY(rts->i_ta, wh->i_addr2);

        m->m_pkthdr.len = m->m_len = sizeof (struct ieee80211_frame_rts);

        return m;
}

static int
rt2560_tx_data(struct rt2560_softc *sc, struct mbuf *m0,
    struct ieee80211_node *ni)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct rt2560_tx_desc *desc;
        struct rt2560_tx_data *data;
        struct rt2560_node *rn;
        struct ieee80211_rateset *rs;
        struct ieee80211_frame *wh;
        struct ieee80211_key *k;
        struct mbuf *mnew;
        uint16_t dur;
        uint32_t flags = 0;
        int rate, error;

        wh = mtod(m0, struct ieee80211_frame *);

        if (ic->ic_fixed_rate != IEEE80211_FIXED_RATE_NONE) {
                rs = &ic->ic_sup_rates[ic->ic_curmode];
                rate = rs->rs_rates[ic->ic_fixed_rate];
        } else {
                rs = &ni->ni_rates;
                rn = (struct rt2560_node *)ni;
                ni->ni_txrate = ieee80211_rssadapt_choose(&rn->rssadapt, rs,
                    wh, m0->m_pkthdr.len, -1, NULL, 0);
                rate = rs->rs_rates[ni->ni_txrate];
        }
        rate &= IEEE80211_RATE_VAL;

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

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

        /*
         * IEEE Std 802.11-1999, pp 82: "A STA shall use an RTS/CTS exchange
         * for directed frames only when the length of the MPDU is greater
         * than the length threshold indicated by [...]" ic_rtsthreshold.
         */
        if (!IEEE80211_IS_MULTICAST(wh->i_addr1) &&
            m0->m_pkthdr.len > ic->ic_rtsthreshold) {
                struct mbuf *m;
                int rtsrate, ackrate;

                rtsrate = IEEE80211_IS_CHAN_5GHZ(ni->ni_chan) ? 12 : 2;
                ackrate = rt2560_ack_rate(ic, rate);

                dur = rt2560_txtime(m0->m_pkthdr.len + 4, rate, ic->ic_flags) +
                      rt2560_txtime(RAL_CTS_SIZE, rtsrate, ic->ic_flags) +
                      rt2560_txtime(RAL_ACK_SIZE, ackrate, ic->ic_flags) +
                      3 * RAL_SIFS;

                m = rt2560_get_rts(sc, wh, dur);

                desc = &sc->txq.desc[sc->txq.cur_encrypt];
                data = &sc->txq.data[sc->txq.cur_encrypt];

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

                /* avoid multiple free() of the same node for each fragment */
                ieee80211_ref_node(ni);

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

                /* RTS frames are not taken into account for rssadapt */
                data->id.id_node = NULL;

                rt2560_setup_tx_desc(sc, desc, RT2560_TX_ACK |
                    RT2560_TX_MORE_FRAG, m->m_pkthdr.len, rtsrate, 1,
                    data->map->dm_segs->ds_addr);

                bus_dmamap_sync(sc->sc_dmat, data->map, 0,
                    data->map->dm_mapsize, BUS_DMASYNC_PREWRITE);
                bus_dmamap_sync(sc->sc_dmat, sc->txq.map,
                    sc->txq.cur_encrypt * RT2560_TX_DESC_SIZE,
                    RT2560_TX_DESC_SIZE, BUS_DMASYNC_PREWRITE);

                sc->txq.queued++;
                sc->txq.cur_encrypt =
                    (sc->txq.cur_encrypt + 1) % RT2560_TX_RING_COUNT;

                /*
                 * IEEE Std 802.11-1999: when an RTS/CTS exchange is used, the
                 * asynchronous data frame shall be transmitted after the CTS
                 * frame and a SIFS period.
                 */
                flags |= RT2560_TX_LONG_RETRY | RT2560_TX_IFS_SIFS;
        }

        data = &sc->txq.data[sc->txq.cur_encrypt];
        desc = &sc->txq.desc[sc->txq.cur_encrypt];

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

                MGETHDR(mnew, M_DONTWAIT, MT_DATA);
                if (mnew == NULL) {
                        m_freem(m0);
                        return ENOMEM;
                }

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

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

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

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

        if (sc->sc_drvbpf != NULL) {
                struct rt2560_tx_radiotap_header *tap = &sc->sc_txtap;

                tap->wt_flags = 0;
                tap->wt_rate = rate;
                tap->wt_chan_freq = htole16(ic->ic_ibss_chan->ic_freq);
                tap->wt_chan_flags = htole16(ic->ic_ibss_chan->ic_flags);
                tap->wt_antenna = sc->tx_ant;

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

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

        /* remember link conditions for rate adaptation algorithm */
        if (ic->ic_fixed_rate == IEEE80211_FIXED_RATE_NONE) {
                data->id.id_len = m0->m_pkthdr.len;
                data->id.id_rateidx = ni->ni_txrate;
                data->id.id_node = ni;
                data->id.id_rssi = ni->ni_rssi;
        } else
                data->id.id_node = NULL;

        if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
                flags |= RT2560_TX_ACK;

                dur = rt2560_txtime(RAL_ACK_SIZE, rt2560_ack_rate(ic, rate),
                    ic->ic_flags) + RAL_SIFS;
                *(uint16_t *)wh->i_dur = htole16(dur);
        }

        rt2560_setup_tx_desc(sc, desc, flags, m0->m_pkthdr.len, rate, 1,
            data->map->dm_segs->ds_addr);

        bus_dmamap_sync(sc->sc_dmat, data->map, 0, data->map->dm_mapsize,
            BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->sc_dmat, sc->txq.map,
            sc->txq.cur_encrypt * RT2560_TX_DESC_SIZE, RT2560_TX_DESC_SIZE,
            BUS_DMASYNC_PREWRITE);

        DPRINTFN(10, ("sending data frame len=%u idx=%u rate=%u\n",
            m0->m_pkthdr.len, sc->txq.cur_encrypt, rate));

        /* kick encrypt */
        sc->txq.queued++;
        sc->txq.cur_encrypt = (sc->txq.cur_encrypt + 1) % RT2560_TX_RING_COUNT;
        RAL_WRITE(sc, RT2560_SECCSR1, RT2560_KICK_ENCRYPT);

        return 0;
}

static void
rt2560_start(struct ifnet *ifp)
{
        struct rt2560_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        struct mbuf *m0;
        struct ieee80211_node *ni;
        struct ether_header *eh;

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

        for (;;) {
                IF_POLL(&ic->ic_mgtq, m0);
                if (m0 != NULL) {
                        if (sc->prioq.queued >= RT2560_PRIO_RING_COUNT) {
                                ifp->if_flags |= IFF_OACTIVE;
                                break;
                        }
                        IF_DEQUEUE(&ic->ic_mgtq, m0);
                        if (m0 == NULL)
                                break;

                        ni = M_GETCTX(m0, struct ieee80211_node *);
                        M_CLEARCTX(m0);
                        bpf_mtap3(ic->ic_rawbpf, m0, BPF_D_OUT);
                        if (rt2560_tx_mgt(sc, m0, ni) != 0)
                                break;

                } else {
                        if (ic->ic_state != IEEE80211_S_RUN)
                                break;
                        IFQ_DEQUEUE(&ifp->if_snd, m0);
                        if (m0 == NULL)
                                break;
                        if (sc->txq.queued >= RT2560_TX_RING_COUNT - 1) {
                                ifp->if_flags |= IFF_OACTIVE;
                                break;
                        }

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

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

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

                        bpf_mtap3(ic->ic_rawbpf, m0, BPF_D_OUT);

                        if (rt2560_tx_data(sc, m0, ni) != 0) {
                                ieee80211_free_node(ni);
                                if_statinc(ifp, if_oerrors);
                                break;
                        }
                }

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

static void
rt2560_watchdog(struct ifnet *ifp)
{
        struct rt2560_softc *sc = ifp->if_softc;

        ifp->if_timer = 0;

        if (sc->sc_tx_timer > 0) {
                if (--sc->sc_tx_timer == 0) {
                        aprint_error_dev(sc->sc_dev, "device timeout\n");
                        rt2560_init(ifp);
                        if_statinc(ifp, if_oerrors);
                        return;
                }
                ifp->if_timer = 1;
        }

        ieee80211_watchdog(&sc->sc_ic);
}

/*
 * This function allows for fast channel switching in monitor mode (used by
 * net-mgmt/kismet). In IBSS mode, we must explicitly reset the interface to
 * generate a new beacon frame.
 */
static int
rt2560_reset(struct ifnet *ifp)
{
        struct rt2560_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;

        if (ic->ic_opmode != IEEE80211_M_MONITOR)
                return ENETRESET;

        rt2560_set_chan(sc, ic->ic_curchan);

        return 0;
}

int
rt2560_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
        struct rt2560_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        int s, error = 0;

        s = splnet();

        switch (cmd) {
        case SIOCSIFFLAGS:
                if ((error = ifioctl_common(ifp, cmd, data)) != 0)
                        break;
                if (ifp->if_flags & IFF_UP) {
                        if (ifp->if_flags & IFF_RUNNING)
                                rt2560_update_promisc(sc);
                        else
                                rt2560_init(ifp);
                } else {
                        if (ifp->if_flags & IFF_RUNNING)
                                rt2560_stop(ifp, 1);
                }
                break;

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

        case SIOCS80211CHANNEL:
                /*
                 * This allows for fast channel switching in monitor mode
                 * (used by kismet). In IBSS mode, we must explicitly reset
                 * the interface to generate a new beacon frame.
                 */
                error = ieee80211_ioctl(ic, cmd, data);
                if (error == ENETRESET &&
                    ic->ic_opmode == IEEE80211_M_MONITOR) {
                        rt2560_set_chan(sc, ic->ic_ibss_chan);
                        error = 0;
                }
                break;

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

        if (error == ENETRESET) {
                if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) ==
                    (IFF_UP | IFF_RUNNING))
                        rt2560_init(ifp);
                error = 0;
        }

        splx(s);

        return error;
}

static void
rt2560_bbp_write(struct rt2560_softc *sc, uint8_t reg, uint8_t val)
{
        uint32_t tmp;
        int ntries;

        for (ntries = 0; ntries < 100; ntries++) {
                if (!(RAL_READ(sc, RT2560_BBPCSR) & RT2560_BBP_BUSY))
                        break;
                DELAY(1);
        }
        if (ntries == 100) {
                aprint_error_dev(sc->sc_dev, "could not write to BBP\n");
                return;
        }

        tmp = RT2560_BBP_WRITE | RT2560_BBP_BUSY | reg << 8 | val;
        RAL_WRITE(sc, RT2560_BBPCSR, tmp);

        DPRINTFN(15, ("BBP R%u <- 0x%02x\n", reg, val));
}

static uint8_t
rt2560_bbp_read(struct rt2560_softc *sc, uint8_t reg)
{
        uint32_t val;
        int ntries;

        val = RT2560_BBP_BUSY | reg << 8;
        RAL_WRITE(sc, RT2560_BBPCSR, val);

        for (ntries = 0; ntries < 100; ntries++) {
                val = RAL_READ(sc, RT2560_BBPCSR);
                if (!(val & RT2560_BBP_BUSY))
                        return val & 0xff;
                DELAY(1);
        }

        aprint_error_dev(sc->sc_dev, "could not read from BBP\n");
        return 0;
}

static void
rt2560_rf_write(struct rt2560_softc *sc, uint8_t reg, uint32_t val)
{
        uint32_t tmp;
        int ntries;

        for (ntries = 0; ntries < 100; ntries++) {
                if (!(RAL_READ(sc, RT2560_RFCSR) & RT2560_RF_BUSY))
                        break;
                DELAY(1);
        }
        if (ntries == 100) {
                aprint_error_dev(sc->sc_dev, "could not write to RF\n");
                return;
        }

        tmp = RT2560_RF_BUSY | RT2560_RF_20BIT | (val & 0xfffff) << 2 |
            (reg & 0x3);
        RAL_WRITE(sc, RT2560_RFCSR, tmp);

        /* remember last written value in sc */
        sc->rf_regs[reg] = val;

        DPRINTFN(15, ("RF R[%u] <- 0x%05x\n", reg & 0x3, val & 0xfffff));
}

static void
rt2560_set_chan(struct rt2560_softc *sc, struct ieee80211_channel *c)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint8_t power, tmp;
        u_int i, chan;

        chan = ieee80211_chan2ieee(ic, c);
        if (chan == 0 || chan == IEEE80211_CHAN_ANY)
                return;

        if (IEEE80211_IS_CHAN_2GHZ(c))
                power = uimin(sc->txpow[chan - 1], 31);
        else
                power = 31;

        DPRINTFN(2, ("setting channel to %u, txpower to %u\n", chan, power));

        switch (sc->rf_rev) {
        case RT2560_RF_2522:
                rt2560_rf_write(sc, RT2560_RF1, 0x00814);
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2522_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x00040);
                break;

        case RT2560_RF_2523:
                rt2560_rf_write(sc, RT2560_RF1, 0x08804);
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2523_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x38044);
                rt2560_rf_write(sc, RT2560_RF4,
                    (chan == 14) ? 0x00280 : 0x00286);
                break;

        case RT2560_RF_2524:
                rt2560_rf_write(sc, RT2560_RF1, 0x0c808);
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2524_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x00040);
                rt2560_rf_write(sc, RT2560_RF4,
                    (chan == 14) ? 0x00280 : 0x00286);
                break;

        case RT2560_RF_2525:
                rt2560_rf_write(sc, RT2560_RF1, 0x08808);
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2525_hi_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x18044);
                rt2560_rf_write(sc, RT2560_RF4,
                    (chan == 14) ? 0x00280 : 0x00286);

                rt2560_rf_write(sc, RT2560_RF1, 0x08808);
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2525_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x18044);
                rt2560_rf_write(sc, RT2560_RF4,
                    (chan == 14) ? 0x00280 : 0x00286);
                break;

        case RT2560_RF_2525E:
                rt2560_rf_write(sc, RT2560_RF1, 0x08808);
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2525e_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x18044);
                rt2560_rf_write(sc, RT2560_RF4,
                    (chan == 14) ? 0x00286 : 0x00282);
                break;

        case RT2560_RF_2526:
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2526_hi_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF4,
                   (chan & 1) ? 0x00386 : 0x00381);
                rt2560_rf_write(sc, RT2560_RF1, 0x08804);

                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf2526_r2[chan - 1]);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x18044);
                rt2560_rf_write(sc, RT2560_RF4,
                    (chan & 1) ? 0x00386 : 0x00381);
                break;

        /* dual-band RF */
        case RT2560_RF_5222:
                for (i = 0; rt2560_rf5222[i].chan != chan; i++);

                rt2560_rf_write(sc, RT2560_RF1, rt2560_rf5222[i].r1);
                rt2560_rf_write(sc, RT2560_RF2, rt2560_rf5222[i].r2);
                rt2560_rf_write(sc, RT2560_RF3, power << 7 | 0x00040);
                rt2560_rf_write(sc, RT2560_RF4, rt2560_rf5222[i].r4);
                break;
        }

        if (ic->ic_opmode != IEEE80211_M_MONITOR &&
            ic->ic_state != IEEE80211_S_SCAN) {
                /* set Japan filter bit for channel 14 */
                tmp = rt2560_bbp_read(sc, 70);

                tmp &= ~RT2560_JAPAN_FILTER;
                if (chan == 14)
                        tmp |= RT2560_JAPAN_FILTER;

                rt2560_bbp_write(sc, 70, tmp);

                DELAY(1000); /* RF needs a 1ms delay here */
                rt2560_disable_rf_tune(sc);

                /* clear CRC errors */
                RAL_READ(sc, RT2560_CNT0);
        }
}

/*
 * Disable RF auto-tuning.
 */
static void
rt2560_disable_rf_tune(struct rt2560_softc *sc)
{
        uint32_t tmp;

        if (sc->rf_rev != RT2560_RF_2523) {
                tmp = sc->rf_regs[RT2560_RF1] & ~RT2560_RF1_AUTOTUNE;
                rt2560_rf_write(sc, RT2560_RF1, tmp);
        }

        tmp = sc->rf_regs[RT2560_RF3] & ~RT2560_RF3_AUTOTUNE;
        rt2560_rf_write(sc, RT2560_RF3, tmp);

        DPRINTFN(2, ("disabling RF autotune\n"));
}

/*
 * Refer to IEEE Std 802.11-1999 pp. 123 for more information on TSF
 * synchronization.
 */
static void
rt2560_enable_tsf_sync(struct rt2560_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        uint16_t logcwmin, preload;
        uint32_t tmp;

        /* first, disable TSF synchronization */
        RAL_WRITE(sc, RT2560_CSR14, 0);

        tmp = 16 * ic->ic_bss->ni_intval;
        RAL_WRITE(sc, RT2560_CSR12, tmp);

        RAL_WRITE(sc, RT2560_CSR13, 0);

        logcwmin = 5;
        preload = (ic->ic_opmode == IEEE80211_M_STA) ? 384 : 1024;
        tmp = logcwmin << 16 | preload;
        RAL_WRITE(sc, RT2560_BCNOCSR, tmp);

        /* finally, enable TSF synchronization */
        tmp = RT2560_ENABLE_TSF | RT2560_ENABLE_TBCN;
        if (ic->ic_opmode == IEEE80211_M_STA)
                tmp |= RT2560_ENABLE_TSF_SYNC(1);
        else
                tmp |= RT2560_ENABLE_TSF_SYNC(2) |
                       RT2560_ENABLE_BEACON_GENERATOR;
        RAL_WRITE(sc, RT2560_CSR14, tmp);

        DPRINTF(("enabling TSF synchronization\n"));
}

static void
rt2560_update_plcp(struct rt2560_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;

        /* no short preamble for 1Mbps */
        RAL_WRITE(sc, RT2560_PLCP1MCSR, 0x00700400);

        if (!(ic->ic_flags & IEEE80211_F_SHPREAMBLE)) {
                /* values taken from the reference driver */
                RAL_WRITE(sc, RT2560_PLCP2MCSR,   0x00380401);
                RAL_WRITE(sc, RT2560_PLCP5p5MCSR, 0x00150402);
                RAL_WRITE(sc, RT2560_PLCP11MCSR,  0x000b8403);
        } else {
                /* same values as above or'ed 0x8 */
                RAL_WRITE(sc, RT2560_PLCP2MCSR,   0x00380409);
                RAL_WRITE(sc, RT2560_PLCP5p5MCSR, 0x0015040a);
                RAL_WRITE(sc, RT2560_PLCP11MCSR,  0x000b840b);
        }

        DPRINTF(("updating PLCP for %s preamble\n",
            (ic->ic_flags & IEEE80211_F_SHPREAMBLE) ? "short" : "long"));
}

/*
 * IEEE 802.11a uses short slot time. Refer to IEEE Std 802.11-1999 pp. 85 to
 * know how these values are computed.
 */
static void
rt2560_update_slot(struct ifnet *ifp)
{
        struct rt2560_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        uint8_t slottime;
        uint16_t sifs, pifs, difs, eifs;
        uint32_t tmp;

        slottime = (ic->ic_flags & IEEE80211_F_SHSLOT) ? 9 : 20;

        /* define the MAC slot boundaries */
        sifs = RAL_SIFS - RT2560_RXTX_TURNAROUND;
        pifs = sifs + slottime;
        difs = sifs + 2 * slottime;
        eifs = (ic->ic_curmode == IEEE80211_MODE_11B) ? 364 : 60;

        tmp = RAL_READ(sc, RT2560_CSR11);
        tmp = (tmp & ~0x1f00) | slottime << 8;
        RAL_WRITE(sc, RT2560_CSR11, tmp);

        tmp = pifs << 16 | sifs;
        RAL_WRITE(sc, RT2560_CSR18, tmp);

        tmp = eifs << 16 | difs;
        RAL_WRITE(sc, RT2560_CSR19, tmp);

        DPRINTF(("setting slottime to %uus\n", slottime));
}

static void
rt2560_set_basicrates(struct rt2560_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;

        /* update basic rate set */
        if (ic->ic_curmode == IEEE80211_MODE_11B) {
                /* 11b basic rates: 1, 2Mbps */
                RAL_WRITE(sc, RT2560_ARSP_PLCP_1, 0x3);
        } else if (IEEE80211_IS_CHAN_5GHZ(ic->ic_bss->ni_chan)) {
                /* 11a basic rates: 6, 12, 24Mbps */
                RAL_WRITE(sc, RT2560_ARSP_PLCP_1, 0x150);
        } else {
                /* 11g basic rates: 1, 2, 5.5, 11, 6, 12, 24Mbps */
                RAL_WRITE(sc, RT2560_ARSP_PLCP_1, 0x15f);
        }
}

static void
rt2560_update_led(struct rt2560_softc *sc, int led1, int led2)
{
        uint32_t tmp;

        /* set ON period to 70ms and OFF period to 30ms */
        tmp = led1 << 16 | led2 << 17 | 70 << 8 | 30;
        RAL_WRITE(sc, RT2560_LEDCSR, tmp);
}

static void
rt2560_set_bssid(struct rt2560_softc *sc, uint8_t *bssid)
{
        uint32_t tmp;

        tmp = bssid[0] | bssid[1] << 8 | bssid[2] << 16 | bssid[3] << 24;
        RAL_WRITE(sc, RT2560_CSR5, tmp);

        tmp = bssid[4] | bssid[5] << 8;
        RAL_WRITE(sc, RT2560_CSR6, tmp);

        DPRINTF(("setting BSSID to %s\n", ether_sprintf(bssid)));
}

static void
rt2560_set_macaddr(struct rt2560_softc *sc, uint8_t *addr)
{
        uint32_t tmp;

        tmp = addr[0] | addr[1] << 8 | addr[2] << 16 | addr[3] << 24;
        RAL_WRITE(sc, RT2560_CSR3, tmp);

        tmp = addr[4] | addr[5] << 8;
        RAL_WRITE(sc, RT2560_CSR4, tmp);

        DPRINTF(("setting MAC address to %s\n", ether_sprintf(addr)));
}

static void
rt2560_get_macaddr(struct rt2560_softc *sc, uint8_t *addr)
{
        uint32_t tmp;

        tmp = RAL_READ(sc, RT2560_CSR3);
        addr[0] = tmp & 0xff;
        addr[1] = (tmp >>  8) & 0xff;
        addr[2] = (tmp >> 16) & 0xff;
        addr[3] = (tmp >> 24);

        tmp = RAL_READ(sc, RT2560_CSR4);
        addr[4] = tmp & 0xff;
        addr[5] = (tmp >> 8) & 0xff;
}

static void
rt2560_update_promisc(struct rt2560_softc *sc)
{
        struct ifnet *ifp = &sc->sc_if;
        uint32_t tmp;

        tmp = RAL_READ(sc, RT2560_RXCSR0);

        tmp &= ~RT2560_DROP_NOT_TO_ME;
        if (!(ifp->if_flags & IFF_PROMISC))
                tmp |= RT2560_DROP_NOT_TO_ME;

        RAL_WRITE(sc, RT2560_RXCSR0, tmp);

        DPRINTF(("%s promiscuous mode\n", (ifp->if_flags & IFF_PROMISC) ?
            "entering" : "leaving"));
}

static void
rt2560_set_txantenna(struct rt2560_softc *sc, int antenna)
{
        uint32_t tmp;
        uint8_t tx;

        tx = rt2560_bbp_read(sc, RT2560_BBP_TX) & ~RT2560_BBP_ANTMASK;
        if (antenna == 1)
                tx |= RT2560_BBP_ANTA;
        else if (antenna == 2)
                tx |= RT2560_BBP_ANTB;
        else
                tx |= RT2560_BBP_DIVERSITY;

        /* need to force I/Q flip for RF 2525e, 2526 and 5222 */
        if (sc->rf_rev == RT2560_RF_2525E || sc->rf_rev == RT2560_RF_2526 ||
            sc->rf_rev == RT2560_RF_5222)
                tx |= RT2560_BBP_FLIPIQ;

        rt2560_bbp_write(sc, RT2560_BBP_TX, tx);

        /* update values for CCK and OFDM in BBPCSR1 */
        tmp = RAL_READ(sc, RT2560_BBPCSR1) & ~0x00070007;
        tmp |= (tx & 0x7) << 16 | (tx & 0x7);
        RAL_WRITE(sc, RT2560_BBPCSR1, tmp);
}

static void
rt2560_set_rxantenna(struct rt2560_softc *sc, int antenna)
{
        uint8_t rx;

        rx = rt2560_bbp_read(sc, RT2560_BBP_RX) & ~RT2560_BBP_ANTMASK;
        if (antenna == 1)
                rx |= RT2560_BBP_ANTA;
        else if (antenna == 2)
                rx |= RT2560_BBP_ANTB;
        else
                rx |= RT2560_BBP_DIVERSITY;

        /* need to force no I/Q flip for RF 2525e and 2526 */
        if (sc->rf_rev == RT2560_RF_2525E || sc->rf_rev == RT2560_RF_2526)
                rx &= ~RT2560_BBP_FLIPIQ;

        rt2560_bbp_write(sc, RT2560_BBP_RX, rx);
}

static const char *
rt2560_get_rf(int rev)
{
        switch (rev) {
        case RT2560_RF_2522:    return "RT2522";
        case RT2560_RF_2523:    return "RT2523";
        case RT2560_RF_2524:    return "RT2524";
        case RT2560_RF_2525:    return "RT2525";
        case RT2560_RF_2525E:   return "RT2525e";
        case RT2560_RF_2526:    return "RT2526";
        case RT2560_RF_5222:    return "RT5222";
        default:                return "unknown";
        }
}

static void
rt2560_read_eeprom(struct rt2560_softc *sc)
{
        uint16_t val;
        int i;

        val = rt2560_eeprom_read(sc, RT2560_EEPROM_CONFIG0);
        sc->rf_rev =   (val >> 11) & 0x1f;
        sc->hw_radio = (val >> 10) & 0x1;
        sc->led_mode = (val >> 6)  & 0x7;
        sc->rx_ant =   (val >> 4)  & 0x3;
        sc->tx_ant =   (val >> 2)  & 0x3;
        sc->nb_ant =   val & 0x3;

        /* read default values for BBP registers */
        for (i = 0; i < 16; i++) {
                val = rt2560_eeprom_read(sc, RT2560_EEPROM_BBP_BASE + i);
                sc->bbp_prom[i].reg = val >> 8;
                sc->bbp_prom[i].val = val & 0xff;
        }

        /* read Tx power for all b/g channels */
        for (i = 0; i < 14 / 2; i++) {
                val = rt2560_eeprom_read(sc, RT2560_EEPROM_TXPOWER + i);
                sc->txpow[i * 2] = val >> 8;
                sc->txpow[i * 2 + 1] = val & 0xff;
        }
}

static int
rt2560_bbp_init(struct rt2560_softc *sc)
{
#define N(a)    (sizeof (a) / sizeof ((a)[0]))
        int i, ntries;

        /* wait for BBP to be ready */
        for (ntries = 0; ntries < 100; ntries++) {
                if (rt2560_bbp_read(sc, RT2560_BBP_VERSION) != 0)
                        break;
                DELAY(1);
        }
        if (ntries == 100) {
                aprint_error_dev(sc->sc_dev, "timeout waiting for BBP\n");
                return EIO;
        }

        /* initialize BBP registers to default values */
        for (i = 0; i < N(rt2560_def_bbp); i++) {
                rt2560_bbp_write(sc, rt2560_def_bbp[i].reg,
                    rt2560_def_bbp[i].val);
        }
#if 0
        /* initialize BBP registers to values stored in EEPROM */
        for (i = 0; i < 16; i++) {
                if (sc->bbp_prom[i].reg == 0xff)
                        continue;
                rt2560_bbp_write(sc, sc->bbp_prom[i].reg, sc->bbp_prom[i].val);
        }
#endif

        return 0;
#undef N
}

static int
rt2560_init(struct ifnet *ifp)
{
#define N(a)    (sizeof (a) / sizeof ((a)[0]))
        struct rt2560_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        uint32_t tmp;
        int i;

        /* for CardBus, power on the socket */
        if (!(sc->sc_flags & RT2560_ENABLED)) {
                if (sc->sc_enable != NULL && (*sc->sc_enable)(sc) != 0) {
                        aprint_error_dev(sc->sc_dev, "could not enable device\n");
                        return EIO;
                }
                sc->sc_flags |= RT2560_ENABLED;
        }

        rt2560_stop(ifp, 1);

        /* setup tx rings */
        tmp = RT2560_PRIO_RING_COUNT << 24 |
              RT2560_ATIM_RING_COUNT << 16 |
              RT2560_TX_RING_COUNT   <<  8 |
              RT2560_TX_DESC_SIZE;

        /* rings _must_ be initialized in this _exact_ order! */
        RAL_WRITE(sc, RT2560_TXCSR2, tmp);
        RAL_WRITE(sc, RT2560_TXCSR3, sc->txq.physaddr);
        RAL_WRITE(sc, RT2560_TXCSR5, sc->prioq.physaddr);
        RAL_WRITE(sc, RT2560_TXCSR4, sc->atimq.physaddr);
        RAL_WRITE(sc, RT2560_TXCSR6, sc->bcnq.physaddr);

        /* setup rx ring */
        tmp = RT2560_RX_RING_COUNT << 8 | RT2560_RX_DESC_SIZE;

        RAL_WRITE(sc, RT2560_RXCSR1, tmp);
        RAL_WRITE(sc, RT2560_RXCSR2, sc->rxq.physaddr);

        /* initialize MAC registers to default values */
        for (i = 0; i < N(rt2560_def_mac); i++)
                RAL_WRITE(sc, rt2560_def_mac[i].reg, rt2560_def_mac[i].val);

        IEEE80211_ADDR_COPY(ic->ic_myaddr, CLLADDR(ifp->if_sadl));
        rt2560_set_macaddr(sc, ic->ic_myaddr);

        /* set basic rate set (will be updated later) */
        RAL_WRITE(sc, RT2560_ARSP_PLCP_1, 0x153);

        rt2560_update_slot(ifp);
        rt2560_update_plcp(sc);
        rt2560_update_led(sc, 0, 0);

        RAL_WRITE(sc, RT2560_CSR1, RT2560_RESET_ASIC);
        RAL_WRITE(sc, RT2560_CSR1, RT2560_HOST_READY);

        if (rt2560_bbp_init(sc) != 0) {
                rt2560_stop(ifp, 1);
                return EIO;
        }

        rt2560_set_txantenna(sc, 1);
        rt2560_set_rxantenna(sc, 1);

        /* set default BSS channel */
        ic->ic_bss->ni_chan = ic->ic_ibss_chan;
        rt2560_set_chan(sc, ic->ic_bss->ni_chan);

        /* kick Rx */
        tmp = RT2560_DROP_PHY_ERROR | RT2560_DROP_CRC_ERROR;
        if (ic->ic_opmode != IEEE80211_M_MONITOR) {
                tmp |= RT2560_DROP_CTL | RT2560_DROP_VERSION_ERROR;
                if (ic->ic_opmode != IEEE80211_M_HOSTAP)
                        tmp |= RT2560_DROP_TODS;
                if (!(ifp->if_flags & IFF_PROMISC))
                        tmp |= RT2560_DROP_NOT_TO_ME;
        }
        RAL_WRITE(sc, RT2560_RXCSR0, tmp);

        /* clear old FCS and Rx FIFO errors */
        RAL_READ(sc, RT2560_CNT0);
        RAL_READ(sc, RT2560_CNT4);

        /* clear any pending interrupts */
        RAL_WRITE(sc, RT2560_CSR7, 0xffffffff);

        /* enable interrupts */
        RAL_WRITE(sc, RT2560_CSR8, RT2560_INTR_MASK);

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

        if (ic->ic_opmode == IEEE80211_M_MONITOR)
                ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
        else
                ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);

        return 0;
#undef N
}

static void
rt2560_stop(struct ifnet *ifp, int disable)
{
        struct rt2560_softc *sc = ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;

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

        ieee80211_new_state(ic, IEEE80211_S_INIT, -1);  /* free all nodes */

        /* abort Tx */
        RAL_WRITE(sc, RT2560_TXCSR0, RT2560_ABORT_TX);

        /* disable Rx */
        RAL_WRITE(sc, RT2560_RXCSR0, RT2560_DISABLE_RX);

        /* reset ASIC (and thus, BBP) */
        RAL_WRITE(sc, RT2560_CSR1, RT2560_RESET_ASIC);
        RAL_WRITE(sc, RT2560_CSR1, 0);

        /* disable interrupts */
        RAL_WRITE(sc, RT2560_CSR8, 0xffffffff);

        /* clear any pending interrupt */
        RAL_WRITE(sc, RT2560_CSR7, 0xffffffff);

        /* reset Tx and Rx rings */
        rt2560_reset_tx_ring(sc, &sc->txq);
        rt2560_reset_tx_ring(sc, &sc->atimq);
        rt2560_reset_tx_ring(sc, &sc->prioq);
        rt2560_reset_tx_ring(sc, &sc->bcnq);
        rt2560_reset_rx_ring(sc, &sc->rxq);
}