root/sys/dev/ic/rtw.c
/* $NetBSD: rtw.c,v 1.137 2021/11/10 16:17:34 msaitoh Exp $ */
/*-
 * Copyright (c) 2004, 2005, 2006, 2007 David Young.  All rights
 * reserved.
 *
 * Programmed for NetBSD by David Young.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY David Young ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL David
 * Young BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 */
/*
 * Device driver for the Realtek RTL8180 802.11 MAC/BBP.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rtw.c,v 1.137 2021/11/10 16:17:34 msaitoh Exp $");


#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/device.h>
#include <sys/sockio.h>

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

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

#include <net80211/ieee80211_netbsd.h>
#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_radiotap.h>

#include <net/bpf.h>

#include <dev/ic/rtwreg.h>
#include <dev/ic/rtwvar.h>
#include <dev/ic/rtwphyio.h>
#include <dev/ic/rtwphy.h>

#include <dev/ic/smc93cx6var.h>

static int rtw_rfprog_fallback = 0;
static int rtw_host_rfio = 0;

#ifdef RTW_DEBUG
int rtw_debug = 0;
static int rtw_rxbufs_limit = RTW_RXQLEN;
#endif /* RTW_DEBUG */

#define NEXT_ATTACH_STATE(sc, state) do {                       \
        DPRINTF(sc, RTW_DEBUG_ATTACH,                           \
            ("%s: attach state %s\n", __func__, #state));       \
        sc->sc_attach_state = state;                            \
} while (0)

int rtw_dwelltime = 200;        /* milliseconds */
static struct ieee80211_cipher rtw_cipher_wep;

static void rtw_disable_interrupts(struct rtw_regs *);
static void rtw_enable_interrupts(struct rtw_softc *);

static int rtw_init(struct ifnet *);
static void rtw_softintr(void *);

static void rtw_start(struct ifnet *);
static void rtw_reset_oactive(struct rtw_softc *);
static struct mbuf *rtw_beacon_alloc(struct rtw_softc *,
    struct ieee80211_node *);
static u_int rtw_txring_next(struct rtw_regs *, struct rtw_txdesc_blk *);

static void rtw_io_enable(struct rtw_softc *, uint8_t, int);
static int rtw_key_delete(struct ieee80211com *, const struct ieee80211_key *);
static int rtw_key_set(struct ieee80211com *, const struct ieee80211_key *,
    const uint8_t[IEEE80211_ADDR_LEN]);
static void rtw_key_update_end(struct ieee80211com *);
static void rtw_key_update_begin(struct ieee80211com *);
static int rtw_wep_decap(struct ieee80211_key *, struct mbuf *, int);
static void rtw_wep_setkeys(struct rtw_softc *, struct ieee80211_key *, int);

static void rtw_led_attach(struct rtw_led_state *, void *);
static void rtw_led_detach(struct rtw_led_state *);
static void rtw_led_init(struct rtw_regs *);
static void rtw_led_slowblink(void *);
static void rtw_led_fastblink(void *);
static void rtw_led_set(struct rtw_led_state *, struct rtw_regs *, int);

static int rtw_sysctl_verify_rfio(SYSCTLFN_PROTO);
static int rtw_sysctl_verify_rfprog(SYSCTLFN_PROTO);
#ifdef RTW_DEBUG
static void rtw_dump_rings(struct rtw_softc *sc);
static void rtw_print_txdesc(struct rtw_softc *, const char *,
    struct rtw_txsoft *, struct rtw_txdesc_blk *, int);
static int rtw_sysctl_verify_debug(SYSCTLFN_PROTO);
static int rtw_sysctl_verify_rxbufs_limit(SYSCTLFN_PROTO);
#endif /* RTW_DEBUG */
#ifdef RTW_DIAG
static void rtw_txring_fixup(struct rtw_softc *sc, const char *fn, int ln);
#endif /* RTW_DIAG */

/*
 * Setup sysctl(3) MIB, hw.rtw.*
 *
 * TBD condition CTLFLAG_PERMANENT on being a module or not
 */
SYSCTL_SETUP(sysctl_rtw, "sysctl rtw(4) subtree setup")
{
        int rc;
        const struct sysctlnode *cnode, *rnode;

        if ((rc = sysctl_createv(clog, 0, NULL, &rnode,
            CTLFLAG_PERMANENT, CTLTYPE_NODE, "rtw",
            "Realtek RTL818x 802.11 controls",
            NULL, 0, NULL, 0, CTL_HW, CTL_CREATE, CTL_EOL)) != 0)
                goto err;

#ifdef RTW_DEBUG
        /* control debugging printfs */
        if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_INT,
            "debug", SYSCTL_DESCR("Enable RTL818x debugging output"),
            rtw_sysctl_verify_debug, 0, &rtw_debug, 0,
            CTL_CREATE, CTL_EOL)) != 0)
                goto err;

        /* Limit rx buffers, for simulating resource exhaustion. */
        if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_INT,
            "rxbufs_limit",
            SYSCTL_DESCR("Set rx buffers limit"),
            rtw_sysctl_verify_rxbufs_limit, 0, &rtw_rxbufs_limit, 0,
            CTL_CREATE, CTL_EOL)) != 0)
                goto err;

#endif /* RTW_DEBUG */
        /* set fallback RF programming method */
        if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_INT,
            "rfprog_fallback",
            SYSCTL_DESCR("Set fallback RF programming method"),
            rtw_sysctl_verify_rfprog, 0, &rtw_rfprog_fallback, 0,
            CTL_CREATE, CTL_EOL)) != 0)
                goto err;

        /* force host to control RF I/O bus */
        if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
            CTLFLAG_PERMANENT | CTLFLAG_READWRITE, CTLTYPE_INT,
            "host_rfio", SYSCTL_DESCR("Enable host control of RF I/O"),
            rtw_sysctl_verify_rfio, 0, &rtw_host_rfio, 0,
            CTL_CREATE, CTL_EOL)) != 0)
                goto err;

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

static int
rtw_sysctl_verify(SYSCTLFN_ARGS, int lower, int upper)
{
        int error, t;
        struct sysctlnode node;

        node = *rnode;
        t = *(int*)rnode->sysctl_data;
        node.sysctl_data = &t;
        error = sysctl_lookup(SYSCTLFN_CALL(&node));
        if (error || newp == NULL)
                return (error);

        if (t < lower || t > upper)
                return (EINVAL);

        *(int*)rnode->sysctl_data = t;

        return (0);
}

static int
rtw_sysctl_verify_rfprog(SYSCTLFN_ARGS)
{
        return rtw_sysctl_verify(SYSCTLFN_CALL(__UNCONST(rnode)), 0,
            __SHIFTOUT(RTW_CONFIG4_RFTYPE_MASK, RTW_CONFIG4_RFTYPE_MASK));
}

static int
rtw_sysctl_verify_rfio(SYSCTLFN_ARGS)
{
        return rtw_sysctl_verify(SYSCTLFN_CALL(__UNCONST(rnode)), 0, 1);
}

#ifdef RTW_DEBUG
static int
rtw_sysctl_verify_debug(SYSCTLFN_ARGS)
{
        return rtw_sysctl_verify(SYSCTLFN_CALL(__UNCONST(rnode)),
            0, RTW_DEBUG_MAX);
}

static int
rtw_sysctl_verify_rxbufs_limit(SYSCTLFN_ARGS)
{
        return rtw_sysctl_verify(SYSCTLFN_CALL(__UNCONST(rnode)),
            0, RTW_RXQLEN);
}

static void
rtw_print_regs(struct rtw_regs *regs, const char *dvname, const char *where)
{
#define PRINTREG32(sc, reg)                             \
        RTW_DPRINTF(RTW_DEBUG_REGDUMP,                  \
            ("%s: reg[ " #reg " / %03x ] = %08x\n",     \
            dvname, reg, RTW_READ(regs, reg)))

#define PRINTREG16(sc, reg)                             \
        RTW_DPRINTF(RTW_DEBUG_REGDUMP,                  \
            ("%s: reg[ " #reg " / %03x ] = %04x\n",     \
            dvname, reg, RTW_READ16(regs, reg)))

#define PRINTREG8(sc, reg)                              \
        RTW_DPRINTF(RTW_DEBUG_REGDUMP,                  \
            ("%s: reg[ " #reg " / %03x ] = %02x\n",     \
            dvname, reg, RTW_READ8(regs, reg)))

        RTW_DPRINTF(RTW_DEBUG_REGDUMP, ("%s: %s\n", dvname, where));

        PRINTREG32(regs, RTW_IDR0);
        PRINTREG32(regs, RTW_IDR1);
        PRINTREG32(regs, RTW_MAR0);
        PRINTREG32(regs, RTW_MAR1);
        PRINTREG32(regs, RTW_TSFTRL);
        PRINTREG32(regs, RTW_TSFTRH);
        PRINTREG32(regs, RTW_TLPDA);
        PRINTREG32(regs, RTW_TNPDA);
        PRINTREG32(regs, RTW_THPDA);
        PRINTREG32(regs, RTW_TCR);
        PRINTREG32(regs, RTW_RCR);
        PRINTREG32(regs, RTW_TINT);
        PRINTREG32(regs, RTW_TBDA);
        PRINTREG32(regs, RTW_ANAPARM);
        PRINTREG32(regs, RTW_BB);
        PRINTREG32(regs, RTW_PHYCFG);
        PRINTREG32(regs, RTW_WAKEUP0L);
        PRINTREG32(regs, RTW_WAKEUP0H);
        PRINTREG32(regs, RTW_WAKEUP1L);
        PRINTREG32(regs, RTW_WAKEUP1H);
        PRINTREG32(regs, RTW_WAKEUP2LL);
        PRINTREG32(regs, RTW_WAKEUP2LH);
        PRINTREG32(regs, RTW_WAKEUP2HL);
        PRINTREG32(regs, RTW_WAKEUP2HH);
        PRINTREG32(regs, RTW_WAKEUP3LL);
        PRINTREG32(regs, RTW_WAKEUP3LH);
        PRINTREG32(regs, RTW_WAKEUP3HL);
        PRINTREG32(regs, RTW_WAKEUP3HH);
        PRINTREG32(regs, RTW_WAKEUP4LL);
        PRINTREG32(regs, RTW_WAKEUP4LH);
        PRINTREG32(regs, RTW_WAKEUP4HL);
        PRINTREG32(regs, RTW_WAKEUP4HH);
        PRINTREG32(regs, RTW_DK0);
        PRINTREG32(regs, RTW_DK1);
        PRINTREG32(regs, RTW_DK2);
        PRINTREG32(regs, RTW_DK3);
        PRINTREG32(regs, RTW_RETRYCTR);
        PRINTREG32(regs, RTW_RDSAR);
        PRINTREG32(regs, RTW_FER);
        PRINTREG32(regs, RTW_FEMR);
        PRINTREG32(regs, RTW_FPSR);
        PRINTREG32(regs, RTW_FFER);

        /* 16-bit registers */
        PRINTREG16(regs, RTW_BRSR);
        PRINTREG16(regs, RTW_IMR);
        PRINTREG16(regs, RTW_ISR);
        PRINTREG16(regs, RTW_BCNITV);
        PRINTREG16(regs, RTW_ATIMWND);
        PRINTREG16(regs, RTW_BINTRITV);
        PRINTREG16(regs, RTW_ATIMTRITV);
        PRINTREG16(regs, RTW_CRC16ERR);
        PRINTREG16(regs, RTW_CRC0);
        PRINTREG16(regs, RTW_CRC1);
        PRINTREG16(regs, RTW_CRC2);
        PRINTREG16(regs, RTW_CRC3);
        PRINTREG16(regs, RTW_CRC4);
        PRINTREG16(regs, RTW_CWR);

        /* 8-bit registers */
        PRINTREG8(regs, RTW_CR);
        PRINTREG8(regs, RTW_9346CR);
        PRINTREG8(regs, RTW_CONFIG0);
        PRINTREG8(regs, RTW_CONFIG1);
        PRINTREG8(regs, RTW_CONFIG2);
        PRINTREG8(regs, RTW_MSR);
        PRINTREG8(regs, RTW_CONFIG3);
        PRINTREG8(regs, RTW_CONFIG4);
        PRINTREG8(regs, RTW_TESTR);
        PRINTREG8(regs, RTW_PSR);
        PRINTREG8(regs, RTW_SCR);
        PRINTREG8(regs, RTW_PHYDELAY);
        PRINTREG8(regs, RTW_CRCOUNT);
        PRINTREG8(regs, RTW_PHYADDR);
        PRINTREG8(regs, RTW_PHYDATAW);
        PRINTREG8(regs, RTW_PHYDATAR);
        PRINTREG8(regs, RTW_CONFIG5);
        PRINTREG8(regs, RTW_TPPOLL);

        PRINTREG16(regs, RTW_BSSID16);
        PRINTREG32(regs, RTW_BSSID32);
#undef PRINTREG32
#undef PRINTREG16
#undef PRINTREG8
}
#endif /* RTW_DEBUG */

void
rtw_continuous_tx_enable(struct rtw_softc *sc, int enable)
{
        struct rtw_regs *regs = &sc->sc_regs;

        uint32_t tcr;
        tcr = RTW_READ(regs, RTW_TCR);
        tcr &= ~RTW_TCR_LBK_MASK;
        if (enable)
                tcr |= RTW_TCR_LBK_CONT;
        else
                tcr |= RTW_TCR_LBK_NORMAL;
        RTW_WRITE(regs, RTW_TCR, tcr);
        RTW_SYNC(regs, RTW_TCR, RTW_TCR);
        rtw_set_access(regs, RTW_ACCESS_ANAPARM);
        rtw_txdac_enable(sc, !enable);
        rtw_set_access(regs, RTW_ACCESS_ANAPARM);/* XXX Voodoo from Linux. */
        rtw_set_access(regs, RTW_ACCESS_NONE);
}

#ifdef RTW_DEBUG
static const char *
rtw_access_string(enum rtw_access access)
{
        switch (access) {
        case RTW_ACCESS_NONE:
                return "none";
        case RTW_ACCESS_CONFIG:
                return "config";
        case RTW_ACCESS_ANAPARM:
                return "anaparm";
        default:
                return "unknown";
        }
}
#endif /* RTW_DEBUG */

static void
rtw_set_access1(struct rtw_regs *regs, enum rtw_access naccess)
{
        KASSERT(/* naccess >= RTW_ACCESS_NONE && */
            naccess <= RTW_ACCESS_ANAPARM);
        KASSERT(/* regs->r_access >= RTW_ACCESS_NONE && */
            regs->r_access <= RTW_ACCESS_ANAPARM);

        if (naccess == regs->r_access)
                return;

        switch (naccess) {
        case RTW_ACCESS_NONE:
                switch (regs->r_access) {
                case RTW_ACCESS_ANAPARM:
                        rtw_anaparm_enable(regs, 0);
                        /*FALLTHROUGH*/
                case RTW_ACCESS_CONFIG:
                        rtw_config0123_enable(regs, 0);
                        /*FALLTHROUGH*/
                case RTW_ACCESS_NONE:
                        break;
                }
                break;
        case RTW_ACCESS_CONFIG:
                switch (regs->r_access) {
                case RTW_ACCESS_NONE:
                        rtw_config0123_enable(regs, 1);
                        /*FALLTHROUGH*/
                case RTW_ACCESS_CONFIG:
                        break;
                case RTW_ACCESS_ANAPARM:
                        rtw_anaparm_enable(regs, 0);
                        break;
                }
                break;
        case RTW_ACCESS_ANAPARM:
                switch (regs->r_access) {
                case RTW_ACCESS_NONE:
                        rtw_config0123_enable(regs, 1);
                        /*FALLTHROUGH*/
                case RTW_ACCESS_CONFIG:
                        rtw_anaparm_enable(regs, 1);
                        /*FALLTHROUGH*/
                case RTW_ACCESS_ANAPARM:
                        break;
                }
                break;
        }
}

void
rtw_set_access(struct rtw_regs *regs, enum rtw_access access)
{
        rtw_set_access1(regs, access);
        RTW_DPRINTF(RTW_DEBUG_ACCESS,
            ("%s: access %s -> %s\n", __func__,
            rtw_access_string(regs->r_access),
            rtw_access_string(access)));
        regs->r_access = access;
}

/*
 * Enable registers, switch register banks.
 */
void
rtw_config0123_enable(struct rtw_regs *regs, int enable)
{
        uint8_t ecr;
        ecr = RTW_READ8(regs, RTW_9346CR);
        ecr &= ~(RTW_9346CR_EEM_MASK | RTW_9346CR_EECS | RTW_9346CR_EESK);
        if (enable)
                ecr |= RTW_9346CR_EEM_CONFIG;
        else {
                RTW_WBW(regs, RTW_9346CR, MAX(RTW_CONFIG0, RTW_CONFIG3));
                ecr |= RTW_9346CR_EEM_NORMAL;
        }
        RTW_WRITE8(regs, RTW_9346CR, ecr);
        RTW_SYNC(regs, RTW_9346CR, RTW_9346CR);
}

/* requires rtw_config0123_enable(, 1) */
void
rtw_anaparm_enable(struct rtw_regs *regs, int enable)
{
        uint8_t cfg3;

        cfg3 = RTW_READ8(regs, RTW_CONFIG3);
        cfg3 |= RTW_CONFIG3_CLKRUNEN;
        if (enable)
                cfg3 |= RTW_CONFIG3_PARMEN;
        else
                cfg3 &= ~RTW_CONFIG3_PARMEN;
        RTW_WRITE8(regs, RTW_CONFIG3, cfg3);
        RTW_SYNC(regs, RTW_CONFIG3, RTW_CONFIG3);
}

/* requires rtw_anaparm_enable(, 1) */
void
rtw_txdac_enable(struct rtw_softc *sc, int enable)
{
        uint32_t anaparm;
        struct rtw_regs *regs = &sc->sc_regs;

        anaparm = RTW_READ(regs, RTW_ANAPARM);
        if (enable)
                anaparm &= ~RTW_ANAPARM_TXDACOFF;
        else
                anaparm |= RTW_ANAPARM_TXDACOFF;
        RTW_WRITE(regs, RTW_ANAPARM, anaparm);
        RTW_SYNC(regs, RTW_ANAPARM, RTW_ANAPARM);
}

static inline int
rtw_chip_reset1(struct rtw_regs *regs, device_t dev)
{
        uint8_t cr;
        int i;

        RTW_WRITE8(regs, RTW_CR, RTW_CR_RST);

        RTW_WBR(regs, RTW_CR, RTW_CR);

        for (i = 0; i < 1000; i++) {
                if ((cr = RTW_READ8(regs, RTW_CR) & RTW_CR_RST) == 0) {
                        RTW_DPRINTF(RTW_DEBUG_RESET,
                            ("%s: reset in %dus\n", device_xname(dev), i));
                        return 0;
                }
                RTW_RBR(regs, RTW_CR, RTW_CR);
                DELAY(10); /* 10us */
        }

        aprint_error_dev(dev, "reset failed\n");
        return ETIMEDOUT;
}

static inline int
rtw_chip_reset(struct rtw_regs *regs, device_t dev)
{
        uint32_t tcr;

        /* from Linux driver */
        tcr = RTW_TCR_CWMIN | RTW_TCR_MXDMA_2048 |
              __SHIFTIN(7, RTW_TCR_SRL_MASK) | __SHIFTIN(7, RTW_TCR_LRL_MASK);

        RTW_WRITE(regs, RTW_TCR, tcr);

        RTW_WBW(regs, RTW_CR, RTW_TCR);

        return rtw_chip_reset1(regs, dev);
}

static int
rtw_wep_decap(struct ieee80211_key *k, struct mbuf *m, int hdrlen)
{
        struct ieee80211_key keycopy;

        RTW_DPRINTF(RTW_DEBUG_KEY, ("%s:\n", __func__));

        keycopy = *k;
        keycopy.wk_flags &= ~IEEE80211_KEY_SWCRYPT;

        return (*ieee80211_cipher_wep.ic_decap)(&keycopy, m, hdrlen);
}

static int
rtw_key_delete(struct ieee80211com *ic, const struct ieee80211_key *k)
{
        struct rtw_softc *sc = ic->ic_ifp->if_softc;

        DPRINTF(sc, RTW_DEBUG_KEY, ("%s: delete key %u\n", __func__,
            k->wk_keyix));

        KASSERT(k->wk_keyix < IEEE80211_WEP_NKID);

        if (k->wk_keylen != 0 &&
            k->wk_cipher->ic_cipher == IEEE80211_CIPHER_WEP)
                sc->sc_flags &= ~RTW_F_DK_VALID;

        return 1;
}

static int
rtw_key_set(struct ieee80211com *ic, const struct ieee80211_key *k,
    const uint8_t mac[IEEE80211_ADDR_LEN])
{
        struct rtw_softc *sc = ic->ic_ifp->if_softc;

        DPRINTF(sc, RTW_DEBUG_KEY, ("%s: set key %u\n", __func__, k->wk_keyix));

        KASSERT(k->wk_keyix < IEEE80211_WEP_NKID);

        sc->sc_flags &= ~RTW_F_DK_VALID;

        return 1;
}

static void
rtw_key_update_begin(struct ieee80211com *ic)
{
#ifdef RTW_DEBUG
        struct ifnet *ifp = ic->ic_ifp;
        struct rtw_softc *sc = ifp->if_softc;
#endif

        DPRINTF(sc, RTW_DEBUG_KEY, ("%s:\n", __func__));
}

static void
rtw_tx_kick(struct rtw_regs *regs, uint8_t ringsel)
{
        uint8_t tppoll;

        tppoll = RTW_READ8(regs, RTW_TPPOLL);
        tppoll &= ~RTW_TPPOLL_SALL;
        tppoll |= ringsel & RTW_TPPOLL_ALL;
        RTW_WRITE8(regs, RTW_TPPOLL, tppoll);
        RTW_SYNC(regs, RTW_TPPOLL, RTW_TPPOLL);
}

static void
rtw_key_update_end(struct ieee80211com *ic)
{
        struct ifnet *ifp = ic->ic_ifp;
        struct rtw_softc *sc = ifp->if_softc;

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

        if ((sc->sc_flags & RTW_F_DK_VALID) != 0 ||
            !device_is_active(sc->sc_dev))
                return;

        rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 0);
        rtw_wep_setkeys(sc, ic->ic_nw_keys, ic->ic_def_txkey);
        rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE,
            (ifp->if_flags & IFF_RUNNING) != 0);
}

static bool
rtw_key_hwsupp(uint32_t flags, const struct ieee80211_key *k)
{
        if (k->wk_cipher->ic_cipher != IEEE80211_CIPHER_WEP)
                return false;

        return  ((flags & RTW_C_RXWEP_40) != 0 && k->wk_keylen == 5) ||
                ((flags & RTW_C_RXWEP_104) != 0 && k->wk_keylen == 13);
}

static void
rtw_wep_setkeys(struct rtw_softc *sc, struct ieee80211_key *wk, int txkey)
{
        uint8_t psr, scr;
        int i, keylen = 0;
        struct rtw_regs *regs;
        union rtw_keys *rk;

        regs = &sc->sc_regs;
        rk = &sc->sc_keys;

        (void)memset(rk, 0, sizeof(*rk));

        /* Temporarily use software crypto for all keys. */
        for (i = 0; i < IEEE80211_WEP_NKID; i++) {
                if (wk[i].wk_cipher == &rtw_cipher_wep)
                        wk[i].wk_cipher = &ieee80211_cipher_wep;
        }

        rtw_set_access(regs, RTW_ACCESS_CONFIG);

        psr = RTW_READ8(regs, RTW_PSR);
        scr = RTW_READ8(regs, RTW_SCR);
        scr &= ~(RTW_SCR_KM_MASK | RTW_SCR_TXSECON | RTW_SCR_RXSECON);

        if ((sc->sc_ic.ic_flags & IEEE80211_F_PRIVACY) == 0)
                goto out;

        for (i = 0; i < IEEE80211_WEP_NKID; i++) {
                if (!rtw_key_hwsupp(sc->sc_flags, &wk[i]))
                        continue;
                if (i == txkey) {
                        keylen = wk[i].wk_keylen;
                        break;
                }
                keylen = MAX(keylen, wk[i].wk_keylen);
        }

        if (keylen == 5)
                scr |= RTW_SCR_KM_WEP40 | RTW_SCR_RXSECON;
        else if (keylen == 13)
                scr |= RTW_SCR_KM_WEP104 | RTW_SCR_RXSECON;

        for (i = 0; i < IEEE80211_WEP_NKID; i++) {
                if (wk[i].wk_keylen != keylen ||
                    wk[i].wk_cipher->ic_cipher != IEEE80211_CIPHER_WEP)
                        continue;
                /* h/w will decrypt, s/w still strips headers */
                wk[i].wk_cipher = &rtw_cipher_wep;
                (void)memcpy(rk->rk_keys[i], wk[i].wk_key, wk[i].wk_keylen);
        }

out:
        RTW_WRITE8(regs, RTW_PSR, psr & ~RTW_PSR_PSEN);

        bus_space_write_region_stream_4(regs->r_bt, regs->r_bh,
            RTW_DK0, rk->rk_words, __arraycount(rk->rk_words));

        bus_space_barrier(regs->r_bt, regs->r_bh, RTW_DK0, sizeof(rk->rk_words),
            BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);

        RTW_DPRINTF(RTW_DEBUG_KEY,
            ("%s.%d: scr %02" PRIx8 ", keylen %d\n", __func__, __LINE__, scr,
             keylen));

        RTW_WBW(regs, RTW_DK0, RTW_PSR);
        RTW_WRITE8(regs, RTW_PSR, psr);
        RTW_WBW(regs, RTW_PSR, RTW_SCR);
        RTW_WRITE8(regs, RTW_SCR, scr);
        RTW_SYNC(regs, RTW_SCR, RTW_SCR);
        rtw_set_access(regs, RTW_ACCESS_NONE);
        sc->sc_flags |= RTW_F_DK_VALID;
}

static inline int
rtw_recall_eeprom(struct rtw_regs *regs, device_t dev)
{
        int i;
        uint8_t ecr;

        ecr = RTW_READ8(regs, RTW_9346CR);
        ecr = (ecr & ~RTW_9346CR_EEM_MASK) | RTW_9346CR_EEM_AUTOLOAD;
        RTW_WRITE8(regs, RTW_9346CR, ecr);

        RTW_WBR(regs, RTW_9346CR, RTW_9346CR);

        /* wait 25ms for completion */
        for (i = 0; i < 250; i++) {
                ecr = RTW_READ8(regs, RTW_9346CR);
                if ((ecr & RTW_9346CR_EEM_MASK) == RTW_9346CR_EEM_NORMAL) {
                        RTW_DPRINTF(RTW_DEBUG_RESET,
                            ("%s: recall EEPROM in %dus\n", device_xname(dev),
                            i * 100));
                        return 0;
                }
                RTW_RBR(regs, RTW_9346CR, RTW_9346CR);
                DELAY(100);
        }
        aprint_error_dev(dev, "recall EEPROM failed\n");
        return ETIMEDOUT;
}

static inline int
rtw_reset(struct rtw_softc *sc)
{
        int rc;
        uint8_t config1;

        sc->sc_flags &= ~RTW_F_DK_VALID;

        if ((rc = rtw_chip_reset(&sc->sc_regs, sc->sc_dev)) != 0)
                return rc;

        rc = rtw_recall_eeprom(&sc->sc_regs, sc->sc_dev);

        config1 = RTW_READ8(&sc->sc_regs, RTW_CONFIG1);
        RTW_WRITE8(&sc->sc_regs, RTW_CONFIG1, config1 & ~RTW_CONFIG1_PMEN);
        /* TBD turn off maximum power saving? */

        return 0;
}

static inline int
rtw_txdesc_dmamaps_create(bus_dma_tag_t dmat, struct rtw_txsoft *descs,
    u_int ndescs)
{
        int i, rc = 0;
        for (i = 0; i < ndescs; i++) {
                rc = bus_dmamap_create(dmat, MCLBYTES, RTW_MAXPKTSEGS, MCLBYTES,
                    0, 0, &descs[i].ts_dmamap);
                if (rc != 0)
                        break;
        }
        return rc;
}

static inline int
rtw_rxdesc_dmamaps_create(bus_dma_tag_t dmat, struct rtw_rxsoft *descs,
    u_int ndescs)
{
        int i, rc = 0;
        for (i = 0; i < ndescs; i++) {
                rc = bus_dmamap_create(dmat, MCLBYTES, 1, MCLBYTES, 0, 0,
                    &descs[i].rs_dmamap);
                if (rc != 0)
                        break;
        }
        return rc;
}

static inline void
rtw_rxdesc_dmamaps_destroy(bus_dma_tag_t dmat, struct rtw_rxsoft *descs,
    u_int ndescs)
{
        int i;
        for (i = 0; i < ndescs; i++) {
                if (descs[i].rs_dmamap != NULL)
                        bus_dmamap_destroy(dmat, descs[i].rs_dmamap);
        }
}

static inline void
rtw_txdesc_dmamaps_destroy(bus_dma_tag_t dmat, struct rtw_txsoft *descs,
    u_int ndescs)
{
        int i;
        for (i = 0; i < ndescs; i++) {
                if (descs[i].ts_dmamap != NULL)
                        bus_dmamap_destroy(dmat, descs[i].ts_dmamap);
        }
}

static inline void
rtw_srom_free(struct rtw_srom *sr)
{
        sr->sr_size = 0;
        if (sr->sr_content == NULL)
                return;
        free(sr->sr_content, M_DEVBUF);
        sr->sr_content = NULL;
}

static void
rtw_srom_defaults(struct rtw_srom *sr, uint32_t *flags,
    uint8_t *cs_threshold, enum rtw_rfchipid *rfchipid, uint32_t *rcr)
{
        *flags |= (RTW_F_DIGPHY | RTW_F_ANTDIV);
        *cs_threshold = RTW_SR_ENERGYDETTHR_DEFAULT;
        *rcr |= RTW_RCR_ENCS1;
        *rfchipid = RTW_RFCHIPID_PHILIPS;
}

static int
rtw_srom_parse(struct rtw_srom *sr, uint32_t *flags, uint8_t *cs_threshold,
    enum rtw_rfchipid *rfchipid, uint32_t *rcr, enum rtw_locale *locale,
    device_t dev)
{
        int i;
        const char *rfname, *paname;
        char scratch[sizeof("unknown 0xXX")];
        uint16_t srom_version;

        *flags &= ~(RTW_F_DIGPHY | RTW_F_DFLANTB | RTW_F_ANTDIV);
        *rcr &= ~(RTW_RCR_ENCS1 | RTW_RCR_ENCS2);

        srom_version = RTW_SR_GET16(sr, RTW_SR_VERSION);

        if (srom_version <= 0x0101) {
                aprint_error_dev(dev,
                    "SROM version %d.%d is not understood, "
                    "limping along with defaults\n",
                    srom_version >> 8, srom_version & 0xff);
                rtw_srom_defaults(sr, flags, cs_threshold, rfchipid, rcr);
                return 0;
        } else {
                aprint_verbose_dev(dev, "SROM version %d.%d\n",
                    srom_version >> 8, srom_version & 0xff);
        }

        uint8_t mac[IEEE80211_ADDR_LEN];
        for (i = 0; i < IEEE80211_ADDR_LEN; i++)
                mac[i] = RTW_SR_GET(sr, RTW_SR_MAC + i);
        __USE(mac);

        RTW_DPRINTF(RTW_DEBUG_ATTACH,
            ("%s: EEPROM MAC %s\n", device_xname(dev), ether_sprintf(mac)));

        *cs_threshold = RTW_SR_GET(sr, RTW_SR_ENERGYDETTHR);

        if ((RTW_SR_GET(sr, RTW_SR_CONFIG2) & RTW_CONFIG2_ANT) != 0)
                *flags |= RTW_F_ANTDIV;

        /* Note well: the sense of the RTW_SR_RFPARM_DIGPHY bit seems
         * to be reversed.
         */
        if ((RTW_SR_GET(sr, RTW_SR_RFPARM) & RTW_SR_RFPARM_DIGPHY) == 0)
                *flags |= RTW_F_DIGPHY;
        if ((RTW_SR_GET(sr, RTW_SR_RFPARM) & RTW_SR_RFPARM_DFLANTB) != 0)
                *flags |= RTW_F_DFLANTB;

        *rcr |= __SHIFTIN(__SHIFTOUT(RTW_SR_GET(sr, RTW_SR_RFPARM),
            RTW_SR_RFPARM_CS_MASK), RTW_RCR_ENCS1);

        if ((RTW_SR_GET(sr, RTW_SR_CONFIG0) & RTW_CONFIG0_WEP104) != 0)
                *flags |= RTW_C_RXWEP_104;

        *flags |= RTW_C_RXWEP_40;       /* XXX */

        *rfchipid = RTW_SR_GET(sr, RTW_SR_RFCHIPID);
        switch (*rfchipid) {
        case RTW_RFCHIPID_GCT:          /* this combo seen in the wild */
                rfname = "GCT GRF5101";
                paname = "Winspring WS9901";
                break;
        case RTW_RFCHIPID_MAXIM:
                rfname = "Maxim MAX2820";       /* guess */
                paname = "Maxim MAX2422";       /* guess */
                break;
        case RTW_RFCHIPID_INTERSIL:
                rfname = "Intersil HFA3873";    /* guess */
                paname = "Intersil <unknown>";
                break;
        case RTW_RFCHIPID_PHILIPS:      /* this combo seen in the wild */
                rfname = "Philips SA2400A";
                paname = "Philips SA2411";
                break;
        case RTW_RFCHIPID_RFMD:
                /* this is the same front-end as an atw(4)! */
                rfname = "RFMD RF2948B, "       /* mentioned in Realtek docs */
                         "LNA: RFMD RF2494, "   /* mentioned in Realtek docs */
                         "SYN: Silicon Labs Si4126";    /* inferred from
                                                         * reference driver
                                                         */
                paname = "RFMD RF2189";         /* mentioned in Realtek docs */
                break;
        case RTW_RFCHIPID_RESERVED:
                rfname = paname = "reserved";
                break;
        default:
                snprintf(scratch, sizeof(scratch), "unknown 0x%02x", *rfchipid);
                rfname = paname = scratch;
        }
        aprint_normal_dev(dev, "RF: %s, PA: %s\n", rfname, paname);

        switch (RTW_SR_GET(sr, RTW_SR_CONFIG0) & RTW_CONFIG0_GL_MASK) {
        case RTW_CONFIG0_GL_USA:
        case _RTW_CONFIG0_GL_USA:
                *locale = RTW_LOCALE_USA;
                break;
        case RTW_CONFIG0_GL_EUROPE:
                *locale = RTW_LOCALE_EUROPE;
                break;
        case RTW_CONFIG0_GL_JAPAN:
                *locale = RTW_LOCALE_JAPAN;
                break;
        default:
                *locale = RTW_LOCALE_UNKNOWN;
                break;
        }
        return 0;
}

/* Returns -1 on failure. */
static int
rtw_srom_read(struct rtw_regs *regs, uint32_t flags, struct rtw_srom *sr,
    device_t dev)
{
        int rc;
        struct seeprom_descriptor sd;
        uint8_t ecr;

        (void)memset(&sd, 0, sizeof(sd));

        ecr = RTW_READ8(regs, RTW_9346CR);

        if ((flags & RTW_F_9356SROM) != 0) {
                RTW_DPRINTF(RTW_DEBUG_ATTACH, ("%s: 93c56 SROM\n",
                    device_xname(dev)));
                sr->sr_size = 256;
                sd.sd_chip = C56_66;
        } else {
                RTW_DPRINTF(RTW_DEBUG_ATTACH, ("%s: 93c46 SROM\n",
                    device_xname(dev)));
                sr->sr_size = 128;
                sd.sd_chip = C46;
        }

        ecr &= ~(RTW_9346CR_EEDI | RTW_9346CR_EEDO | RTW_9346CR_EESK |
            RTW_9346CR_EEM_MASK | RTW_9346CR_EECS);
        ecr |= RTW_9346CR_EEM_PROGRAM;

        RTW_WRITE8(regs, RTW_9346CR, ecr);

        sr->sr_content = malloc(sr->sr_size, M_DEVBUF, M_WAITOK | M_ZERO);

        /* RTL8180 has a single 8-bit register for controlling the
         * 93cx6 SROM.  There is no "ready" bit. The RTL8180
         * input/output sense is the reverse of read_seeprom's.
         */
        sd.sd_tag = regs->r_bt;
        sd.sd_bsh = regs->r_bh;
        sd.sd_regsize = 1;
        sd.sd_control_offset = RTW_9346CR;
        sd.sd_status_offset = RTW_9346CR;
        sd.sd_dataout_offset = RTW_9346CR;
        sd.sd_CK = RTW_9346CR_EESK;
        sd.sd_CS = RTW_9346CR_EECS;
        sd.sd_DI = RTW_9346CR_EEDO;
        sd.sd_DO = RTW_9346CR_EEDI;
        /* make read_seeprom enter EEPROM read/write mode */
        sd.sd_MS = ecr;
        sd.sd_RDY = 0;

        /* TBD bus barriers */
        if (!read_seeprom(&sd, sr->sr_content, 0, sr->sr_size/2)) {
                aprint_error_dev(dev, "could not read SROM\n");
                free(sr->sr_content, M_DEVBUF);
                sr->sr_content = NULL;
                return -1;      /* XXX */
        }

        /* end EEPROM read/write mode */
        RTW_WRITE8(regs, RTW_9346CR,
            (ecr & ~RTW_9346CR_EEM_MASK) | RTW_9346CR_EEM_NORMAL);
        RTW_WBRW(regs, RTW_9346CR, RTW_9346CR);

        if ((rc = rtw_recall_eeprom(regs, dev)) != 0)
                return rc;

#ifdef RTW_DEBUG
        {
                int i;
                RTW_DPRINTF(RTW_DEBUG_ATTACH,
                    ("\n%s: serial ROM:\n\t", device_xname(dev)));
                for (i = 0; i < sr->sr_size/2; i++) {
                        if (((i % 8) == 0) && (i != 0))
                                RTW_DPRINTF(RTW_DEBUG_ATTACH, ("\n\t"));
                        RTW_DPRINTF(RTW_DEBUG_ATTACH,
                            (" %04x", sr->sr_content[i]));
                }
                RTW_DPRINTF(RTW_DEBUG_ATTACH, ("\n"));
        }
#endif /* RTW_DEBUG */
        return 0;
}

static void
rtw_set_rfprog(struct rtw_regs *regs, enum rtw_rfchipid rfchipid,
    device_t dev)
{
        uint8_t cfg4;
        const char *method;

        cfg4 = RTW_READ8(regs, RTW_CONFIG4) & ~RTW_CONFIG4_RFTYPE_MASK;

        switch (rfchipid) {
        default:
                cfg4 |= __SHIFTIN(rtw_rfprog_fallback, RTW_CONFIG4_RFTYPE_MASK);
                method = "fallback";
                break;
        case RTW_RFCHIPID_INTERSIL:
                cfg4 |= RTW_CONFIG4_RFTYPE_INTERSIL;
                method = "Intersil";
                break;
        case RTW_RFCHIPID_PHILIPS:
                cfg4 |= RTW_CONFIG4_RFTYPE_PHILIPS;
                method = "Philips";
                break;
        case RTW_RFCHIPID_GCT:  /* XXX a guess */
        case RTW_RFCHIPID_RFMD:
                cfg4 |= RTW_CONFIG4_RFTYPE_RFMD;
                method = "RFMD";
                break;
        }

        RTW_WRITE8(regs, RTW_CONFIG4, cfg4);

        RTW_WBR(regs, RTW_CONFIG4, RTW_CONFIG4);

#ifdef RTW_DEBUG
        RTW_DPRINTF(RTW_DEBUG_INIT,
            ("%s: %s RF programming method, %#02x\n", device_xname(dev), method,
            RTW_READ8(regs, RTW_CONFIG4)));
#else
        __USE(method);
#endif
}

static inline void
rtw_init_channels(enum rtw_locale locale,
    struct ieee80211_channel (*chans)[IEEE80211_CHAN_MAX+1], device_t dev)
{
        int i;
        const char *name = NULL;
#define ADD_CHANNEL(_chans, _chan) do {                 \
        (*_chans)[_chan].ic_flags = IEEE80211_CHAN_B;           \
        (*_chans)[_chan].ic_freq =                              \
            ieee80211_ieee2mhz(_chan, (*_chans)[_chan].ic_flags);\
} while (0)

        switch (locale) {
        case RTW_LOCALE_USA:    /* 1-11 */
                name = "USA";
                for (i = 1; i <= 11; i++)
                        ADD_CHANNEL(chans, i);
                break;
        case RTW_LOCALE_JAPAN:  /* 1-14 */
                name = "Japan";
                ADD_CHANNEL(chans, 14);
                for (i = 1; i <= 14; i++)
                        ADD_CHANNEL(chans, i);
                break;
        case RTW_LOCALE_EUROPE: /* 1-13 */
                name = "Europe";
                for (i = 1; i <= 13; i++)
                        ADD_CHANNEL(chans, i);
                break;
        default:                        /* 10-11 allowed by most countries */
                name = "<unknown>";
                for (i = 10; i <= 11; i++)
                        ADD_CHANNEL(chans, i);
                break;
        }
        aprint_normal_dev(dev, "Geographic Location %s\n", name);
#undef ADD_CHANNEL
}


static inline void
rtw_identify_country(struct rtw_regs *regs, enum rtw_locale *locale)
{
        uint8_t cfg0 = RTW_READ8(regs, RTW_CONFIG0);

        switch (cfg0 & RTW_CONFIG0_GL_MASK) {
        case RTW_CONFIG0_GL_USA:
        case _RTW_CONFIG0_GL_USA:
                *locale = RTW_LOCALE_USA;
                break;
        case RTW_CONFIG0_GL_JAPAN:
                *locale = RTW_LOCALE_JAPAN;
                break;
        case RTW_CONFIG0_GL_EUROPE:
                *locale = RTW_LOCALE_EUROPE;
                break;
        default:
                *locale = RTW_LOCALE_UNKNOWN;
                break;
        }
}

static inline int
rtw_identify_sta(struct rtw_regs *regs, uint8_t (*addr)[IEEE80211_ADDR_LEN],
    device_t dev)
{
        static const uint8_t empty_macaddr[IEEE80211_ADDR_LEN] = {
                0x00, 0x00, 0x00, 0x00, 0x00, 0x00
        };
        uint32_t idr0 = RTW_READ(regs, RTW_IDR0),
                 idr1 = RTW_READ(regs, RTW_IDR1);

        (*addr)[0] = __SHIFTOUT(idr0, __BITS(0,  7));
        (*addr)[1] = __SHIFTOUT(idr0, __BITS(8,  15));
        (*addr)[2] = __SHIFTOUT(idr0, __BITS(16, 23));
        (*addr)[3] = __SHIFTOUT(idr0, __BITS(24, 31));

        (*addr)[4] = __SHIFTOUT(idr1, __BITS(0,  7));
        (*addr)[5] = __SHIFTOUT(idr1, __BITS(8, 15));

        if (IEEE80211_ADDR_EQ(addr, empty_macaddr)) {
                aprint_error_dev(dev,
                    "could not get mac address, attach failed\n");
                return ENXIO;
        }

        aprint_normal_dev(dev, "802.11 address %s\n", ether_sprintf(*addr));

        return 0;
}

static uint8_t
rtw_chan2txpower(struct rtw_srom *sr, struct ieee80211com *ic,
    struct ieee80211_channel *chan)
{
        u_int idx = RTW_SR_TXPOWER1 + ieee80211_chan2ieee(ic, chan) - 1;
        KASSERT(idx >= RTW_SR_TXPOWER1 && idx <= RTW_SR_TXPOWER14);
        return RTW_SR_GET(sr, idx);
}

static void
rtw_txdesc_blk_init_all(struct rtw_txdesc_blk *tdb)
{
        int pri;
        /* nfree: the number of free descriptors in each ring.
         * The beacon ring is a special case: I do not let the
         * driver use all of the descriptors on the beacon ring.
         * The reasons are two-fold:
         *
         * (1) A BEACON descriptor's OWN bit is (apparently) not
         * updated, so the driver cannot easily know if the descriptor
         * belongs to it, or if it is racing the NIC.  If the NIC
         * does not OWN every descriptor, then the driver can safely
         * update the descriptors when RTW_TBDA points at tdb_next.
         *
         * (2) I hope that the NIC will process more than one BEACON
         * descriptor in a single beacon interval, since that will
         * enable multiple-BSS support.  Since the NIC does not
         * clear the OWN bit, there is no natural place for it to
         * stop processing BEACON descriptors.  Maybe it will *not*
         * stop processing them!  I do not want to chance the NIC
         * looping around and around a saturated beacon ring, so
         * I will leave one descriptor unOWNed at all times.
         */
        u_int nfree[RTW_NTXPRI] =
            {RTW_NTXDESCLO, RTW_NTXDESCMD, RTW_NTXDESCHI,
             RTW_NTXDESCBCN - 1};

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tdb[pri].tdb_nfree = nfree[pri];
                tdb[pri].tdb_next = 0;
        }
}

static int
rtw_txsoft_blk_init(struct rtw_txsoft_blk *tsb)
{
        int i;
        struct rtw_txsoft *ts;

        SIMPLEQ_INIT(&tsb->tsb_dirtyq);
        SIMPLEQ_INIT(&tsb->tsb_freeq);
        for (i = 0; i < tsb->tsb_ndesc; i++) {
                ts = &tsb->tsb_desc[i];
                ts->ts_mbuf = NULL;
                SIMPLEQ_INSERT_TAIL(&tsb->tsb_freeq, ts, ts_q);
        }
        tsb->tsb_tx_timer = 0;
        return 0;
}

static void
rtw_txsoft_blk_init_all(struct rtw_txsoft_blk *tsb)
{
        int pri;
        for (pri = 0; pri < RTW_NTXPRI; pri++)
                rtw_txsoft_blk_init(&tsb[pri]);
}

static inline void
rtw_rxdescs_sync(struct rtw_rxdesc_blk *rdb, int desc0, int nsync, int ops)
{
        KASSERT(nsync <= rdb->rdb_ndesc);
        /* sync to end of ring */
        if (desc0 + nsync > rdb->rdb_ndesc) {
                bus_dmamap_sync(rdb->rdb_dmat, rdb->rdb_dmamap,
                    offsetof(struct rtw_descs, hd_rx[desc0]),
                    sizeof(struct rtw_rxdesc) * (rdb->rdb_ndesc - desc0), ops);
                nsync -= (rdb->rdb_ndesc - desc0);
                desc0 = 0;
        }

        KASSERT(desc0 < rdb->rdb_ndesc);
        KASSERT(nsync <= rdb->rdb_ndesc);
        KASSERT(desc0 + nsync <= rdb->rdb_ndesc);

        /* sync what remains */
        bus_dmamap_sync(rdb->rdb_dmat, rdb->rdb_dmamap,
            offsetof(struct rtw_descs, hd_rx[desc0]),
            sizeof(struct rtw_rxdesc) * nsync, ops);
}

static void
rtw_txdescs_sync(struct rtw_txdesc_blk *tdb, u_int desc0, u_int nsync, int ops)
{
        /* sync to end of ring */
        if (desc0 + nsync > tdb->tdb_ndesc) {
                bus_dmamap_sync(tdb->tdb_dmat, tdb->tdb_dmamap,
                    tdb->tdb_ofs + sizeof(struct rtw_txdesc) * desc0,
                    sizeof(struct rtw_txdesc) * (tdb->tdb_ndesc - desc0),
                    ops);
                nsync -= (tdb->tdb_ndesc - desc0);
                desc0 = 0;
        }

        /* sync what remains */
        bus_dmamap_sync(tdb->tdb_dmat, tdb->tdb_dmamap,
            tdb->tdb_ofs + sizeof(struct rtw_txdesc) * desc0,
            sizeof(struct rtw_txdesc) * nsync, ops);
}

static void
rtw_txdescs_sync_all(struct rtw_txdesc_blk *tdb)
{
        int pri;
        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                rtw_txdescs_sync(&tdb[pri], 0, tdb[pri].tdb_ndesc,
                    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
        }
}

static void
rtw_rxbufs_release(bus_dma_tag_t dmat, struct rtw_rxsoft *desc)
{
        int i;
        struct rtw_rxsoft *rs;

        for (i = 0; i < RTW_RXQLEN; i++) {
                rs = &desc[i];
                if (rs->rs_mbuf == NULL)
                        continue;
                bus_dmamap_sync(dmat, rs->rs_dmamap, 0,
                    rs->rs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
                bus_dmamap_unload(dmat, rs->rs_dmamap);
                m_freem(rs->rs_mbuf);
                rs->rs_mbuf = NULL;
        }
}

static inline int
rtw_rxsoft_alloc(bus_dma_tag_t dmat, struct rtw_rxsoft *rs)
{
        int rc;
        struct mbuf *m;

        MGETHDR(m, M_DONTWAIT, MT_DATA);
        if (m == NULL)
                return ENOBUFS;

        MCLGET(m, M_DONTWAIT);
        if ((m->m_flags & M_EXT) == 0) {
                m_freem(m);
                return ENOBUFS;
        }

        m->m_pkthdr.len = m->m_len = m->m_ext.ext_size;

        if (rs->rs_mbuf != NULL)
                bus_dmamap_unload(dmat, rs->rs_dmamap);

        rs->rs_mbuf = NULL;

        rc = bus_dmamap_load_mbuf(dmat, rs->rs_dmamap, m, BUS_DMA_NOWAIT);
        if (rc != 0) {
                m_freem(m);
                return -1;
        }

        rs->rs_mbuf = m;

        return 0;
}

static int
rtw_rxsoft_init_all(bus_dma_tag_t dmat, struct rtw_rxsoft *desc,
    int *ndesc, device_t dev)
{
        int i, rc = 0;
        struct rtw_rxsoft *rs;

        for (i = 0; i < RTW_RXQLEN; i++) {
                rs = &desc[i];
                /* we're in rtw_init, so there should be no mbufs allocated */
                KASSERT(rs->rs_mbuf == NULL);
#ifdef RTW_DEBUG
                if (i == rtw_rxbufs_limit) {
                        aprint_error_dev(dev, "TEST hit %d-buffer limit\n", i);
                        rc = ENOBUFS;
                        break;
                }
#endif /* RTW_DEBUG */
                if ((rc = rtw_rxsoft_alloc(dmat, rs)) != 0) {
                        aprint_error_dev(dev,
                            "rtw_rxsoft_alloc failed, %d buffers, rc %d\n",
                            i, rc);
                        break;
                }
        }
        *ndesc = i;
        return rc;
}

static inline void
rtw_rxdesc_init(struct rtw_rxdesc_blk *rdb, struct rtw_rxsoft *rs,
    int idx, int kick)
{
        int is_last = (idx == rdb->rdb_ndesc - 1);
        uint32_t ctl, octl, obuf;
        struct rtw_rxdesc *rd = &rdb->rdb_desc[idx];

        /* sync the mbuf before the descriptor */
        bus_dmamap_sync(rdb->rdb_dmat, rs->rs_dmamap, 0,
            rs->rs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);

        obuf = rd->rd_buf;
        rd->rd_buf = htole32(rs->rs_dmamap->dm_segs[0].ds_addr);

        ctl = __SHIFTIN(rs->rs_mbuf->m_len, RTW_RXCTL_LENGTH_MASK) |
            RTW_RXCTL_OWN | RTW_RXCTL_FS | RTW_RXCTL_LS;

        if (is_last)
                ctl |= RTW_RXCTL_EOR;

        octl = rd->rd_ctl;
        rd->rd_ctl = htole32(ctl);

#ifdef RTW_DEBUG
        RTW_DPRINTF(
            kick ? (RTW_DEBUG_RECV_DESC | RTW_DEBUG_IO_KICK)
                 : RTW_DEBUG_RECV_DESC,
            ("%s: rd %p buf %08x -> %08x ctl %08x -> %08x\n", __func__, rd,
             le32toh(obuf), le32toh(rd->rd_buf), le32toh(octl),
             le32toh(rd->rd_ctl)));
#else
        __USE(octl);
        __USE(obuf);
#endif

        /* sync the descriptor */
        bus_dmamap_sync(rdb->rdb_dmat, rdb->rdb_dmamap,
            RTW_DESC_OFFSET(hd_rx, idx), sizeof(struct rtw_rxdesc),
            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
}

static void
rtw_rxdesc_init_all(struct rtw_rxdesc_blk *rdb, struct rtw_rxsoft *ctl, int kick)
{
        int i;
        struct rtw_rxsoft *rs;

        for (i = 0; i < rdb->rdb_ndesc; i++) {
                rs = &ctl[i];
                rtw_rxdesc_init(rdb, rs, i, kick);
        }
}

static void
rtw_io_enable(struct rtw_softc *sc, uint8_t flags, int enable)
{
        struct rtw_regs *regs = &sc->sc_regs;
        uint8_t cr;

        RTW_DPRINTF(RTW_DEBUG_IOSTATE, ("%s: %s 0x%02x\n", __func__,
            enable ? "enable" : "disable", flags));

        cr = RTW_READ8(regs, RTW_CR);

        /* XXX reference source does not enable MULRW */
        /* enable PCI Read/Write Multiple */
        cr |= RTW_CR_MULRW;

        /* The receive engine will always start at RDSAR.  */
        if (enable && (flags & ~cr & RTW_CR_RE)) {
                struct rtw_rxdesc_blk *rdb;
                rdb = &sc->sc_rxdesc_blk;
                rdb->rdb_next = 0;
        }

        RTW_RBW(regs, RTW_CR, RTW_CR);  /* XXX paranoia? */
        if (enable)
                cr |= flags;
        else
                cr &= ~flags;
        RTW_WRITE8(regs, RTW_CR, cr);
        RTW_SYNC(regs, RTW_CR, RTW_CR);

#ifdef RTW_DIAG
        if (cr & RTW_CR_TE)
                rtw_txring_fixup(sc, __func__, __LINE__);
#endif
        if (cr & RTW_CR_TE) {
                rtw_tx_kick(&sc->sc_regs,
                    RTW_TPPOLL_HPQ | RTW_TPPOLL_NPQ | RTW_TPPOLL_LPQ);
        }
}

static void
rtw_intr_rx(struct rtw_softc *sc, uint16_t isr)
{
#define IS_BEACON(__fc0)                                                \
    ((__fc0 & (IEEE80211_FC0_TYPE_MASK | IEEE80211_FC0_SUBTYPE_MASK)) ==\
     (IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_BEACON))

        static const int ratetbl[4] = {2, 4, 11, 22};   /* convert rates:
                                                         * hardware -> net80211
                                                         */
        u_int next, nproc = 0;
        int hwrate, len, rate, rssi, sq, s;
        uint32_t hrssi, hstat, htsfth, htsftl;
        struct rtw_rxdesc *rd;
        struct rtw_rxsoft *rs;
        struct rtw_rxdesc_blk *rdb;
        struct mbuf *m;
        struct ifnet *ifp = &sc->sc_if;

        struct ieee80211_node *ni;
        struct ieee80211_frame_min *wh;

        rdb = &sc->sc_rxdesc_blk;

        for (next = rdb->rdb_next; ; next = rdb->rdb_next) {
                KASSERT(next < rdb->rdb_ndesc);

                rtw_rxdescs_sync(rdb, next, 1,
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                rd = &rdb->rdb_desc[next];
                rs = &sc->sc_rxsoft[next];

                hstat = le32toh(rd->rd_stat);
                hrssi = le32toh(rd->rd_rssi);
                htsfth = le32toh(rd->rd_tsfth);
                htsftl = le32toh(rd->rd_tsftl);

                RTW_DPRINTF(RTW_DEBUG_RECV_DESC,
                    ("%s: rxdesc[%d] hstat %08x hrssi %08x htsft %08x%08x\n",
                    __func__, next, hstat, hrssi, htsfth, htsftl));

                ++nproc;

                /* still belongs to NIC */
                if ((hstat & RTW_RXSTAT_OWN) != 0) {
                        rtw_rxdescs_sync(rdb, next, 1, BUS_DMASYNC_PREREAD);
                        break;
                }

                /* ieee80211_input() might reset the receive engine
                 * (e.g. by indirectly calling rtw_tune()), so save
                 * the next pointer here and retrieve it again on
                 * the next round.
                 */
                rdb->rdb_next = (next + 1) % rdb->rdb_ndesc;

#ifdef RTW_DEBUG
#define PRINTSTAT(flag) do { \
        if ((hstat & flag) != 0) { \
                printf("%s" #flag, delim); \
                delim = ","; \
        } \
} while (0)
                if ((rtw_debug & RTW_DEBUG_RECV_DESC) != 0) {
                        const char *delim = "<";
                        printf("%s: ", device_xname(sc->sc_dev));
                        if ((hstat & RTW_RXSTAT_DEBUG) != 0) {
                                printf("status %08x", hstat);
                                PRINTSTAT(RTW_RXSTAT_SPLCP);
                                PRINTSTAT(RTW_RXSTAT_MAR);
                                PRINTSTAT(RTW_RXSTAT_PAR);
                                PRINTSTAT(RTW_RXSTAT_BAR);
                                PRINTSTAT(RTW_RXSTAT_PWRMGT);
                                PRINTSTAT(RTW_RXSTAT_CRC32);
                                PRINTSTAT(RTW_RXSTAT_ICV);
                                printf(">, ");
                        }
                }
#endif /* RTW_DEBUG */

                if ((hstat & RTW_RXSTAT_IOERROR) != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "DMA error/FIFO overflow %08" PRIx32 ", "
                            "rx descriptor %d\n", hstat, next);
                        if_statinc(ifp, if_ierrors);
                        goto next;
                }

                len = __SHIFTOUT(hstat, RTW_RXSTAT_LENGTH_MASK);
                if (len < IEEE80211_MIN_LEN) {
                        sc->sc_ic.ic_stats.is_rx_tooshort++;
                        goto next;
                }
                if (len > rs->rs_mbuf->m_len) {
                        aprint_error_dev(sc->sc_dev,
                            "rx frame too long, %d > %d, %08" PRIx32
                            ", desc %d\n",
                            len, rs->rs_mbuf->m_len, hstat, next);
                        if_statinc(ifp, if_ierrors);
                        goto next;
                }

                hwrate = __SHIFTOUT(hstat, RTW_RXSTAT_RATE_MASK);
                if (hwrate >= __arraycount(ratetbl)) {
                        aprint_error_dev(sc->sc_dev,
                            "unknown rate #%" __PRIuBITS "\n",
                            __SHIFTOUT(hstat, RTW_RXSTAT_RATE_MASK));
                        if_statinc(ifp, if_ierrors);
                        goto next;
                }
                rate = ratetbl[hwrate];

#ifdef RTW_DEBUG
                RTW_DPRINTF(RTW_DEBUG_RECV_DESC,
                    ("rate %d.%d Mb/s, time %08x%08x\n", (rate * 5) / 10,
                     (rate * 5) % 10, htsfth, htsftl));
#endif /* RTW_DEBUG */

                /* if bad flags, skip descriptor */
                if ((hstat & RTW_RXSTAT_ONESEG) != RTW_RXSTAT_ONESEG) {
                        aprint_error_dev(sc->sc_dev, "too many rx segments, "
                            "next=%d, %08" PRIx32 "\n", next, hstat);
                        goto next;
                }

                bus_dmamap_sync(sc->sc_dmat, rs->rs_dmamap, 0,
                    rs->rs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);

                m = rs->rs_mbuf;

                /* if temporarily out of memory, re-use mbuf */
                switch (rtw_rxsoft_alloc(sc->sc_dmat, rs)) {
                case 0:
                        break;
                case ENOBUFS:
                        aprint_error_dev(sc->sc_dev,
                            "rtw_rxsoft_alloc(, %d) failed, dropping packet\n",
                            next);
                        goto next;
                default:
                        /* XXX shorten rx ring, instead? */
                        aprint_error_dev(sc->sc_dev,
                            "could not load DMA map\n");
                }

                sq = __SHIFTOUT(hrssi, RTW_RXRSSI_SQ);

                if (sc->sc_rfchipid == RTW_RFCHIPID_PHILIPS)
                        rssi = UINT8_MAX - sq;
                else {
                        rssi = __SHIFTOUT(hrssi, RTW_RXRSSI_IMR_RSSI);
                        /* TBD find out each front-end's LNA gain in the
                         * front-end's units
                         */
                        if ((hrssi & RTW_RXRSSI_IMR_LNA) == 0)
                                rssi |= 0x80;
                }

                /* Note well: now we cannot recycle the rs_mbuf unless
                 * we restore its original length.
                 */
                m_set_rcvif(m, ifp);
                m->m_pkthdr.len = m->m_len = len;

                wh = mtod(m, struct ieee80211_frame_min *);

                s = splnet();

                if (!IS_BEACON(wh->i_fc[0]))
                        sc->sc_led_state.ls_event |= RTW_LED_S_RX;

                sc->sc_tsfth = htsfth;

#ifdef RTW_DEBUG
                if ((ifp->if_flags & (IFF_DEBUG | IFF_LINK2)) ==
                    (IFF_DEBUG | IFF_LINK2)) {
                        ieee80211_dump_pkt(mtod(m, uint8_t *), m->m_pkthdr.len,
                            rate, rssi);
                }
#endif /* RTW_DEBUG */

                if (sc->sc_radiobpf != NULL) {
                        struct rtw_rx_radiotap_header *rr = &sc->sc_rxtap;

                        rr->rr_tsft =
                            htole64(((uint64_t)htsfth << 32) | htsftl);

                        rr->rr_flags = IEEE80211_RADIOTAP_F_FCS;

                        if ((hstat & RTW_RXSTAT_SPLCP) != 0)
                                rr->rr_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
                        if ((hstat & RTW_RXSTAT_CRC32) != 0)
                                rr->rr_flags |= IEEE80211_RADIOTAP_F_BADFCS;

                        rr->rr_rate = rate;

                        if (sc->sc_rfchipid == RTW_RFCHIPID_PHILIPS)
                                rr->rr_u.u_philips.p_antsignal = rssi;
                        else {
                                rr->rr_u.u_other.o_antsignal = rssi;
                                rr->rr_u.u_other.o_barker_lock =
                                    htole16(UINT8_MAX - sq);
                        }

                        bpf_mtap2(sc->sc_radiobpf,
                            rr, sizeof(sc->sc_rxtapu), m, BPF_D_IN);
                }

                if ((hstat & RTW_RXSTAT_RES) != 0) {
                        m_freem(m);
                        splx(s);
                        goto next;
                }

                /* CRC is included with the packet; trim it off. */
                m_adj(m, -IEEE80211_CRC_LEN);

                /* TBD use _MAR, _BAR, _PAR flags as hints to _find_rxnode? */
                ni = ieee80211_find_rxnode(&sc->sc_ic, wh);
                ieee80211_input(&sc->sc_ic, m, ni, rssi, htsftl);
                ieee80211_free_node(ni);
                splx(s);
next:
                rtw_rxdesc_init(rdb, rs, next, 0);
        }
#undef IS_BEACON
}

static void
rtw_txsoft_release(bus_dma_tag_t dmat, struct ieee80211com *ic,
    struct rtw_txsoft *ts)
{
        struct mbuf *m;
        struct ieee80211_node *ni;

        m = ts->ts_mbuf;
        ni = ts->ts_ni;
        KASSERT(m != NULL);
        KASSERT(ni != NULL);
        ts->ts_mbuf = NULL;
        ts->ts_ni = NULL;

        bus_dmamap_sync(dmat, ts->ts_dmamap, 0, ts->ts_dmamap->dm_mapsize,
            BUS_DMASYNC_POSTWRITE);
        bus_dmamap_unload(dmat, ts->ts_dmamap);
        m_freem(m);
        ieee80211_free_node(ni);
}

static void
rtw_txsofts_release(bus_dma_tag_t dmat, struct ieee80211com *ic,
    struct rtw_txsoft_blk *tsb)
{
        struct rtw_txsoft *ts;

        while ((ts = SIMPLEQ_FIRST(&tsb->tsb_dirtyq)) != NULL) {
                rtw_txsoft_release(dmat, ic, ts);
                SIMPLEQ_REMOVE_HEAD(&tsb->tsb_dirtyq, ts_q);
                SIMPLEQ_INSERT_TAIL(&tsb->tsb_freeq, ts, ts_q);
        }
        tsb->tsb_tx_timer = 0;
}

static inline void
rtw_collect_txpkt(struct rtw_softc *sc, struct rtw_txdesc_blk *tdb,
    struct rtw_txsoft *ts, int ndesc)
{
        uint32_t hstat;
        int data_retry, rts_retry;
        struct rtw_txdesc *tdn;
        const char *condstring;
        struct ifnet *ifp = &sc->sc_if;

        rtw_txsoft_release(sc->sc_dmat, &sc->sc_ic, ts);

        tdb->tdb_nfree += ndesc;

        tdn = &tdb->tdb_desc[ts->ts_last];

        hstat = le32toh(tdn->td_stat);
        rts_retry = __SHIFTOUT(hstat, RTW_TXSTAT_RTSRETRY_MASK);
        data_retry = __SHIFTOUT(hstat, RTW_TXSTAT_DRC_MASK);

        if (rts_retry + data_retry)
                if_statadd(ifp, if_collisions, rts_retry + data_retry);

        if ((hstat & RTW_TXSTAT_TOK) != 0)
                condstring = "ok";
        else {
                if_statinc(ifp, if_oerrors);
                condstring = "error";
        }

#ifdef RTW_DEBUG
        DPRINTF(sc, RTW_DEBUG_XMIT_DESC,
            ("%s: ts %p txdesc[%d, %d] %s tries rts %u data %u\n",
            device_xname(sc->sc_dev), ts, ts->ts_first, ts->ts_last,
            condstring, rts_retry, data_retry));
#else
        __USE(condstring);
#endif
}

static void
rtw_reset_oactive(struct rtw_softc *sc)
{
        short oflags;
        int pri;
        struct rtw_txsoft_blk *tsb;
        struct rtw_txdesc_blk *tdb;
        oflags = sc->sc_if.if_flags;
        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tsb = &sc->sc_txsoft_blk[pri];
                tdb = &sc->sc_txdesc_blk[pri];
                if (!SIMPLEQ_EMPTY(&tsb->tsb_freeq) && tdb->tdb_nfree > 0)
                        sc->sc_if.if_flags &= ~IFF_OACTIVE;
        }
        if (oflags != sc->sc_if.if_flags) {
                DPRINTF(sc, RTW_DEBUG_OACTIVE,
                    ("%s: reset OACTIVE\n", __func__));
        }
}

/* Collect transmitted packets. */
static bool
rtw_collect_txring(struct rtw_softc *sc, struct rtw_txsoft_blk *tsb,
    struct rtw_txdesc_blk *tdb, int force)
{
        bool collected = false;
        int ndesc;
        struct rtw_txsoft *ts;

#ifdef RTW_DEBUG
        rtw_dump_rings(sc);
#endif

        while ((ts = SIMPLEQ_FIRST(&tsb->tsb_dirtyq)) != NULL) {
                /* If we're clearing a failed transmission, only clear
                   up to the last packet the hardware has processed.  */
                if (ts->ts_first == rtw_txring_next(&sc->sc_regs, tdb))
                        break;

                ndesc = 1 + ts->ts_last - ts->ts_first;
                if (ts->ts_last < ts->ts_first)
                        ndesc += tdb->tdb_ndesc;

                KASSERT(ndesc > 0);

                rtw_txdescs_sync(tdb, ts->ts_first, ndesc,
                    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);

                if (force) {
                        int next;
#ifdef RTW_DIAG
                        printf("%s: clearing packet, stats", __func__);
#endif
                        for (next = ts->ts_first; ;
                            next = RTW_NEXT_IDX(tdb, next)) {
#ifdef RTW_DIAG
                                printf(" %" PRIx32 "/%" PRIx32 "/%" PRIx32 "/%" PRIu32 "/%" PRIx32, le32toh(tdb->tdb_desc[next].td_stat), le32toh(tdb->tdb_desc[next].td_ctl1), le32toh(tdb->tdb_desc[next].td_buf), le32toh(tdb->tdb_desc[next].td_len), le32toh(tdb->tdb_desc[next].td_next));
#endif
                                tdb->tdb_desc[next].td_stat &=
                                    ~htole32(RTW_TXSTAT_OWN);
                                if (next == ts->ts_last)
                                        break;
                        }
                        rtw_txdescs_sync(tdb, ts->ts_first, ndesc,
                            BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
#ifdef RTW_DIAG
                        next = RTW_NEXT_IDX(tdb, next);
                        printf(" -> end %u stat %" PRIx32 ", was %u\n", next,
                            le32toh(tdb->tdb_desc[next].td_stat),
                            rtw_txring_next(&sc->sc_regs, tdb));
#endif
                } else if ((tdb->tdb_desc[ts->ts_last].td_stat &
                    htole32(RTW_TXSTAT_OWN)) != 0) {
                        rtw_txdescs_sync(tdb, ts->ts_last, 1,
                            BUS_DMASYNC_PREREAD);
                        break;
                }

                collected = true;

                rtw_collect_txpkt(sc, tdb, ts, ndesc);
                SIMPLEQ_REMOVE_HEAD(&tsb->tsb_dirtyq, ts_q);
                SIMPLEQ_INSERT_TAIL(&tsb->tsb_freeq, ts, ts_q);
        }

        /* no more pending transmissions, cancel watchdog */
        if (ts == NULL)
                tsb->tsb_tx_timer = 0;
        rtw_reset_oactive(sc);

        return collected;
}

static void
rtw_intr_tx(struct rtw_softc *sc, uint16_t isr)
{
        int pri, s;
        struct rtw_txsoft_blk   *tsb;
        struct rtw_txdesc_blk   *tdb;
        struct ifnet *ifp = &sc->sc_if;

        s = splnet();

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tsb = &sc->sc_txsoft_blk[pri];
                tdb = &sc->sc_txdesc_blk[pri];
                rtw_collect_txring(sc, tsb, tdb, 0);
        }

        if ((isr & RTW_INTR_TX) != 0)
                rtw_start(ifp); /* in softint */

        splx(s);
}

static void
rtw_intr_beacon(struct rtw_softc *sc, uint16_t isr)
{
        u_int next;
        uint32_t tsfth, tsftl;
        struct ieee80211com *ic;
        struct rtw_txdesc_blk *tdb = &sc->sc_txdesc_blk[RTW_TXPRIBCN];
        struct rtw_txsoft_blk *tsb = &sc->sc_txsoft_blk[RTW_TXPRIBCN];
        struct mbuf *m;
        int s;

        s = splnet();

        tsfth = RTW_READ(&sc->sc_regs, RTW_TSFTRH);
        tsftl = RTW_READ(&sc->sc_regs, RTW_TSFTRL);

        if ((isr & (RTW_INTR_TBDOK | RTW_INTR_TBDER)) != 0) {
                next = rtw_txring_next(&sc->sc_regs, tdb);
#ifdef RTW_DEBUG
                RTW_DPRINTF(RTW_DEBUG_BEACON,
                    ("%s: beacon ring %sprocessed, isr = %#04" PRIx16
                     ", next %u expected %u, %" PRIu64 "\n", __func__,
                     (next == tdb->tdb_next) ? "" : "un", isr, next,
                     tdb->tdb_next, (uint64_t)tsfth << 32 | tsftl));
#else
                __USE(next);
                __USE(tsfth);
                __USE(tsftl);
#endif
                if ((RTW_READ8(&sc->sc_regs, RTW_TPPOLL) & RTW_TPPOLL_BQ) == 0)
                        rtw_collect_txring(sc, tsb, tdb, 1);
        }
        /* Start beacon transmission. */

        if ((isr & RTW_INTR_BCNINT) != 0 &&
            sc->sc_ic.ic_state == IEEE80211_S_RUN &&
            SIMPLEQ_EMPTY(&tsb->tsb_dirtyq)) {
                RTW_DPRINTF(RTW_DEBUG_BEACON,
                    ("%s: beacon prep. time, isr = %#04" PRIx16
                     ", %16" PRIu64 "\n", __func__, isr,
                     (uint64_t)tsfth << 32 | tsftl));
                ic = &sc->sc_ic;
                m = rtw_beacon_alloc(sc, ic->ic_bss);

                if (m == NULL) {
                        aprint_error_dev(sc->sc_dev,
                            "could not allocate beacon\n");
                        splx(s);
                        return;
                }
                M_SETCTX(m, ieee80211_ref_node(ic->ic_bss));
                IF_ENQUEUE(&sc->sc_beaconq, m);
                rtw_start(&sc->sc_if); /* in softint */
        }

        splx(s);
}

static void
rtw_intr_atim(struct rtw_softc *sc)
{
        /* TBD */
        return;
}

#ifdef RTW_DEBUG
static void
rtw_dump_rings(struct rtw_softc *sc)
{
        struct rtw_txdesc_blk *tdb;
        struct rtw_rxdesc *rd;
        struct rtw_rxdesc_blk *rdb;
        int desc, pri;

        if ((rtw_debug & RTW_DEBUG_IO_KICK) == 0)
                return;

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tdb = &sc->sc_txdesc_blk[pri];
                printf("%s: txpri %d ndesc %d nfree %d\n", __func__, pri,
                    tdb->tdb_ndesc, tdb->tdb_nfree);
                for (desc = 0; desc < tdb->tdb_ndesc; desc++)
                        rtw_print_txdesc(sc, ".", NULL, tdb, desc);
        }

        rdb = &sc->sc_rxdesc_blk;

        for (desc = 0; desc < RTW_RXQLEN; desc++) {
                rd = &rdb->rdb_desc[desc];
                printf("%s: %sctl %08x rsvd0/rssi %08x buf/tsftl %08x "
                    "rsvd1/tsfth %08x\n", __func__,
                    (desc >= rdb->rdb_ndesc) ? "UNUSED " : "",
                    le32toh(rd->rd_ctl), le32toh(rd->rd_rssi),
                    le32toh(rd->rd_buf), le32toh(rd->rd_tsfth));
        }
}
#endif /* RTW_DEBUG */

static void
rtw_hwring_setup(struct rtw_softc *sc)
{
        int pri;
        struct rtw_regs *regs = &sc->sc_regs;
        struct rtw_txdesc_blk *tdb;

        sc->sc_txdesc_blk[RTW_TXPRILO].tdb_basereg = RTW_TLPDA;
        sc->sc_txdesc_blk[RTW_TXPRILO].tdb_base = RTW_RING_BASE(sc, hd_txlo);
        sc->sc_txdesc_blk[RTW_TXPRIMD].tdb_basereg = RTW_TNPDA;
        sc->sc_txdesc_blk[RTW_TXPRIMD].tdb_base = RTW_RING_BASE(sc, hd_txmd);
        sc->sc_txdesc_blk[RTW_TXPRIHI].tdb_basereg = RTW_THPDA;
        sc->sc_txdesc_blk[RTW_TXPRIHI].tdb_base = RTW_RING_BASE(sc, hd_txhi);
        sc->sc_txdesc_blk[RTW_TXPRIBCN].tdb_basereg = RTW_TBDA;
        sc->sc_txdesc_blk[RTW_TXPRIBCN].tdb_base = RTW_RING_BASE(sc, hd_bcn);

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tdb = &sc->sc_txdesc_blk[pri];
                RTW_WRITE(regs, tdb->tdb_basereg, tdb->tdb_base);
                RTW_DPRINTF(RTW_DEBUG_XMIT_DESC,
                    ("%s: reg[tdb->tdb_basereg] <- %" PRIxPTR "\n", __func__,
                     (uintptr_t)tdb->tdb_base));
        }

        RTW_WRITE(regs, RTW_RDSAR, RTW_RING_BASE(sc, hd_rx));

        RTW_DPRINTF(RTW_DEBUG_RECV_DESC,
            ("%s: reg[RDSAR] <- %" PRIxPTR "\n", __func__,
             (uintptr_t)RTW_RING_BASE(sc, hd_rx)));

        RTW_SYNC(regs, RTW_TLPDA, RTW_RDSAR);

}

static int
rtw_swring_setup(struct rtw_softc *sc)
{
        int rc;
        struct rtw_rxdesc_blk *rdb;

        rtw_txdesc_blk_init_all(&sc->sc_txdesc_blk[0]);

        rtw_txsoft_blk_init_all(&sc->sc_txsoft_blk[0]);

        rdb = &sc->sc_rxdesc_blk;
        if ((rc = rtw_rxsoft_init_all(sc->sc_dmat, sc->sc_rxsoft, &rdb->rdb_ndesc,
             sc->sc_dev)) != 0 && rdb->rdb_ndesc == 0) {
                aprint_error_dev(sc->sc_dev, "could not allocate rx buffers\n");
                return rc;
        }

        rdb = &sc->sc_rxdesc_blk;
        rtw_rxdescs_sync(rdb, 0, rdb->rdb_ndesc,
            BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
        rtw_rxdesc_init_all(rdb, sc->sc_rxsoft, 1);
        rdb->rdb_next = 0;

        rtw_txdescs_sync_all(&sc->sc_txdesc_blk[0]);
        return 0;
}

static void
rtw_txdesc_blk_init(struct rtw_txdesc_blk *tdb)
{
        int i;

        (void)memset(tdb->tdb_desc, 0,
            sizeof(tdb->tdb_desc[0]) * tdb->tdb_ndesc);
        for (i = 0; i < tdb->tdb_ndesc; i++)
                tdb->tdb_desc[i].td_next = htole32(RTW_NEXT_DESC(tdb, i));
}

static u_int
rtw_txring_next(struct rtw_regs *regs, struct rtw_txdesc_blk *tdb)
{
        return (le32toh(RTW_READ(regs, tdb->tdb_basereg)) - tdb->tdb_base) /
            sizeof(struct rtw_txdesc);
}

#ifdef RTW_DIAG
static void
rtw_txring_fixup(struct rtw_softc *sc, const char *fn, int ln)
{
        int pri;
        u_int next;
        struct rtw_txdesc_blk *tdb;
        struct rtw_regs *regs = &sc->sc_regs;

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                int i;
                tdb = &sc->sc_txdesc_blk[pri];
                next = rtw_txring_next(regs, tdb);
                if (tdb->tdb_next == next)
                        continue;
                for (i = 0; next != tdb->tdb_next;
                    next = RTW_NEXT_IDX(tdb, next), i++) {
                        if ((tdb->tdb_desc[next].td_stat & htole32(RTW_TXSTAT_OWN)) == 0)
                                break;
                }
                printf("%s:%d: tx-ring %d expected next %u, read %u+%d -> %s\n", fn,
                    ln, pri, tdb->tdb_next, next, i, tdb->tdb_next == next ? "okay" : "BAD");
                if (tdb->tdb_next == next)
                        continue;
                tdb->tdb_next = MIN(next, tdb->tdb_ndesc - 1);
        }
}
#endif

static void
rtw_txdescs_reset(struct rtw_softc *sc)
{
        int pri;
        struct rtw_txsoft_blk   *tsb;
        struct rtw_txdesc_blk   *tdb;

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tsb = &sc->sc_txsoft_blk[pri];
                tdb = &sc->sc_txdesc_blk[pri];
                rtw_collect_txring(sc, tsb, tdb, 1);
#ifdef RTW_DIAG
                if (!SIMPLEQ_EMPTY(&tsb->tsb_dirtyq))
                        printf("%s: packets left in ring %d\n", __func__, pri);
#endif
        }
}

static void
rtw_intr_ioerror(struct rtw_softc *sc, uint16_t isr)
{
        int s;

        aprint_error_dev(sc->sc_dev, "tx fifo underflow\n");

        RTW_DPRINTF(RTW_DEBUG_BUGS, ("%s: cleaning up xmit, isr %" PRIx16
            "\n", device_xname(sc->sc_dev), isr));

        s = splnet();

#ifdef RTW_DEBUG
        rtw_dump_rings(sc);
#endif /* RTW_DEBUG */

        /* Collect tx'd packets.  XXX let's hope this stops the transmit
         * timeouts.
         */
        rtw_txdescs_reset(sc);

#ifdef RTW_DEBUG
        rtw_dump_rings(sc);
#endif /* RTW_DEBUG */

        splx(s);
}

static inline void
rtw_suspend_ticks(struct rtw_softc *sc)
{
        RTW_DPRINTF(RTW_DEBUG_TIMEOUT,
            ("%s: suspending ticks\n", device_xname(sc->sc_dev)));
        sc->sc_do_tick = 0;
}

static inline void
rtw_resume_ticks(struct rtw_softc *sc)
{
        uint32_t tsftrl0, tsftrl1, next_tint;

        tsftrl0 = RTW_READ(&sc->sc_regs, RTW_TSFTRL);

        tsftrl1 = RTW_READ(&sc->sc_regs, RTW_TSFTRL);
        next_tint = tsftrl1 + 1000000;
        RTW_WRITE(&sc->sc_regs, RTW_TINT, next_tint);

        sc->sc_do_tick = 1;

#ifdef RTW_DEBUG
        RTW_DPRINTF(RTW_DEBUG_TIMEOUT,
            ("%s: resume ticks delta %#08x now %#08x next %#08x\n",
            device_xname(sc->sc_dev), tsftrl1 - tsftrl0, tsftrl1, next_tint));
#else
        __USE(tsftrl0);
#endif
}

static void
rtw_intr_timeout(struct rtw_softc *sc)
{
        int s;

        s = splnet();
        RTW_DPRINTF(RTW_DEBUG_TIMEOUT, ("%s: timeout\n", device_xname(sc->sc_dev)));
        if (sc->sc_do_tick)
                rtw_resume_ticks(sc);
        splx(s);
}

int
rtw_intr(void *arg)
{
        struct rtw_softc *sc = arg;
        struct rtw_regs *regs = &sc->sc_regs;
        uint16_t isr;
        struct ifnet *ifp = &sc->sc_if;

        /*
         * If the interface isn't running, the interrupt couldn't
         * possibly have come from us.
         */
        if ((ifp->if_flags & IFF_RUNNING) == 0 ||
            !device_activation(sc->sc_dev, DEVACT_LEVEL_DRIVER)) {
                RTW_DPRINTF(RTW_DEBUG_INTR, ("%s: stray interrupt\n",
                    device_xname(sc->sc_dev)));
                return (0);
        }

        isr = RTW_READ16(regs, RTW_ISR);
        if (isr == 0)
                return (0);

        /* Disable interrupts. */
        RTW_WRITE16(regs, RTW_IMR, 0);
        RTW_WBW(regs, RTW_IMR, RTW_IMR);

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

static void
rtw_softintr(void *arg)
{
        int i;
        struct rtw_softc *sc = arg;
        struct rtw_regs *regs = &sc->sc_regs;
        uint16_t isr;
        struct ifnet *ifp = &sc->sc_if;

        if ((ifp->if_flags & IFF_RUNNING) == 0 ||
            !device_activation(sc->sc_dev, DEVACT_LEVEL_DRIVER)) {
                RTW_DPRINTF(RTW_DEBUG_INTR, ("%s: stray interrupt\n",
                    device_xname(sc->sc_dev)));
                return;
        }

        for (i = 0; i < 10; i++) {
                isr = RTW_READ16(regs, RTW_ISR);

                RTW_WRITE16(regs, RTW_ISR, isr);
                RTW_WBR(regs, RTW_ISR, RTW_ISR);

                if (sc->sc_intr_ack != NULL)
                        (*sc->sc_intr_ack)(regs);

                if (isr == 0)
                        break;

#ifdef RTW_DEBUG
#define PRINTINTR(flag) do { \
        if ((isr & flag) != 0) { \
                printf("%s" #flag, delim); \
                delim = ","; \
        } \
} while (0)

                if ((rtw_debug & RTW_DEBUG_INTR) != 0 && isr != 0) {
                        const char *delim = "<";

                        printf("%s: reg[ISR] = %x", device_xname(sc->sc_dev),
                            isr);

                        PRINTINTR(RTW_INTR_TXFOVW);
                        PRINTINTR(RTW_INTR_TIMEOUT);
                        PRINTINTR(RTW_INTR_BCNINT);
                        PRINTINTR(RTW_INTR_ATIMINT);
                        PRINTINTR(RTW_INTR_TBDER);
                        PRINTINTR(RTW_INTR_TBDOK);
                        PRINTINTR(RTW_INTR_THPDER);
                        PRINTINTR(RTW_INTR_THPDOK);
                        PRINTINTR(RTW_INTR_TNPDER);
                        PRINTINTR(RTW_INTR_TNPDOK);
                        PRINTINTR(RTW_INTR_RXFOVW);
                        PRINTINTR(RTW_INTR_RDU);
                        PRINTINTR(RTW_INTR_TLPDER);
                        PRINTINTR(RTW_INTR_TLPDOK);
                        PRINTINTR(RTW_INTR_RER);
                        PRINTINTR(RTW_INTR_ROK);

                        printf(">\n");
                }
#undef PRINTINTR
#endif /* RTW_DEBUG */

                if ((isr & RTW_INTR_RX) != 0)
                        rtw_intr_rx(sc, isr);
                if ((isr & RTW_INTR_TX) != 0)
                        rtw_intr_tx(sc, isr);
                if ((isr & RTW_INTR_BEACON) != 0)
                        rtw_intr_beacon(sc, isr);
                if ((isr & RTW_INTR_ATIMINT) != 0)
                        rtw_intr_atim(sc);
                if ((isr & RTW_INTR_IOERROR) != 0)
                        rtw_intr_ioerror(sc, isr);
                if ((isr & RTW_INTR_TIMEOUT) != 0)
                        rtw_intr_timeout(sc);
        }
        if (i == 10)
                softint_schedule(sc->sc_soft_ih);

        /* Re-enable interrupts */
        RTW_WRITE16(regs, RTW_IMR, sc->sc_inten);
        RTW_WBW(regs, RTW_IMR, RTW_IMR);
}

/* Must be called at splnet. */
static void
rtw_stop(struct ifnet *ifp, int disable)
{
        int pri;
        struct rtw_softc *sc = (struct rtw_softc *)ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        struct rtw_regs *regs = &sc->sc_regs;

        rtw_suspend_ticks(sc);

        ieee80211_new_state(ic, IEEE80211_S_INIT, -1);

        if (device_has_power(sc->sc_dev)) {
                /* Disable interrupts. */
                RTW_WRITE16(regs, RTW_IMR, 0);

                RTW_WBW(regs, RTW_TPPOLL, RTW_IMR);

                /* Stop the transmit and receive processes. First stop DMA,
                 * then disable receiver and transmitter.
                 */
                RTW_WRITE8(regs, RTW_TPPOLL, RTW_TPPOLL_SALL);

                RTW_SYNC(regs, RTW_TPPOLL, RTW_IMR);

                rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 0);
        }

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                rtw_txsofts_release(sc->sc_dmat, &sc->sc_ic,
                    &sc->sc_txsoft_blk[pri]);
        }

        rtw_rxbufs_release(sc->sc_dmat, &sc->sc_rxsoft[0]);

        /* Mark the interface as not running.  Cancel the watchdog timer. */
        ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
        ifp->if_timer = 0;

        if (disable)
                pmf_device_suspend(sc->sc_dev, &sc->sc_qual);

        return;
}

const char *
rtw_pwrstate_string(enum rtw_pwrstate power)
{
        switch (power) {
        case RTW_ON:
                return "on";
        case RTW_SLEEP:
                return "sleep";
        case RTW_OFF:
                return "off";
        default:
                return "unknown";
        }
}

/* XXX For Maxim, I am using the RFMD settings gleaned from the
 * reference driver, plus a magic Maxim "ON" value that comes from
 * the Realtek document "Windows PG for Rtl8180."
 */
static void
rtw_maxim_pwrstate(struct rtw_regs *regs, enum rtw_pwrstate power,
    int before_rf, int digphy)
{
        uint32_t anaparm;

        anaparm = RTW_READ(regs, RTW_ANAPARM);
        anaparm &= ~(RTW_ANAPARM_RFPOW_MASK | RTW_ANAPARM_TXDACOFF);

        switch (power) {
        case RTW_OFF:
                if (before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_MAXIM_OFF;
                anaparm |= RTW_ANAPARM_TXDACOFF;
                break;
        case RTW_SLEEP:
                if (!before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_MAXIM_SLEEP;
                anaparm |= RTW_ANAPARM_TXDACOFF;
                break;
        case RTW_ON:
                if (!before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_MAXIM_ON;
                break;
        }
        RTW_DPRINTF(RTW_DEBUG_PWR,
            ("%s: power state %s, %s RF, reg[ANAPARM] <- %08x\n",
            __func__, rtw_pwrstate_string(power),
            (before_rf) ? "before" : "after", anaparm));

        RTW_WRITE(regs, RTW_ANAPARM, anaparm);
        RTW_SYNC(regs, RTW_ANAPARM, RTW_ANAPARM);
}

/* XXX I am using the RFMD settings gleaned from the reference
 * driver.  They agree
 */
static void
rtw_rfmd_pwrstate(struct rtw_regs *regs, enum rtw_pwrstate power,
    int before_rf, int digphy)
{
        uint32_t anaparm;

        anaparm = RTW_READ(regs, RTW_ANAPARM);
        anaparm &= ~(RTW_ANAPARM_RFPOW_MASK | RTW_ANAPARM_TXDACOFF);

        switch (power) {
        case RTW_OFF:
                if (before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_RFMD_OFF;
                anaparm |= RTW_ANAPARM_TXDACOFF;
                break;
        case RTW_SLEEP:
                if (!before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_RFMD_SLEEP;
                anaparm |= RTW_ANAPARM_TXDACOFF;
                break;
        case RTW_ON:
                if (!before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_RFMD_ON;
                break;
        }
        RTW_DPRINTF(RTW_DEBUG_PWR,
            ("%s: power state %s, %s RF, reg[ANAPARM] <- %08x\n",
            __func__, rtw_pwrstate_string(power),
            (before_rf) ? "before" : "after", anaparm));

        RTW_WRITE(regs, RTW_ANAPARM, anaparm);
        RTW_SYNC(regs, RTW_ANAPARM, RTW_ANAPARM);
}

static void
rtw_philips_pwrstate(struct rtw_regs *regs, enum rtw_pwrstate power,
    int before_rf, int digphy)
{
        uint32_t anaparm;

        anaparm = RTW_READ(regs, RTW_ANAPARM);
        anaparm &= ~(RTW_ANAPARM_RFPOW_MASK | RTW_ANAPARM_TXDACOFF);

        switch (power) {
        case RTW_OFF:
                if (before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_PHILIPS_OFF;
                anaparm |= RTW_ANAPARM_TXDACOFF;
                break;
        case RTW_SLEEP:
                if (!before_rf)
                        return;
                anaparm |= RTW_ANAPARM_RFPOW_PHILIPS_SLEEP;
                anaparm |= RTW_ANAPARM_TXDACOFF;
                break;
        case RTW_ON:
                if (!before_rf)
                        return;
                if (digphy) {
                        anaparm |= RTW_ANAPARM_RFPOW_DIG_PHILIPS_ON;
                        /* XXX guess */
                        anaparm |= RTW_ANAPARM_TXDACOFF;
                } else
                        anaparm |= RTW_ANAPARM_RFPOW_ANA_PHILIPS_ON;
                break;
        }
        RTW_DPRINTF(RTW_DEBUG_PWR,
            ("%s: power state %s, %s RF, reg[ANAPARM] <- %08x\n",
            __func__, rtw_pwrstate_string(power),
            (before_rf) ? "before" : "after", anaparm));

        RTW_WRITE(regs, RTW_ANAPARM, anaparm);
        RTW_SYNC(regs, RTW_ANAPARM, RTW_ANAPARM);
}

static void
rtw_pwrstate0(struct rtw_softc *sc, enum rtw_pwrstate power, int before_rf,
    int digphy)
{
        struct rtw_regs *regs = &sc->sc_regs;

        rtw_set_access(regs, RTW_ACCESS_ANAPARM);

        (*sc->sc_pwrstate_cb)(regs, power, before_rf, digphy);

        rtw_set_access(regs, RTW_ACCESS_NONE);

        return;
}

static int
rtw_pwrstate(struct rtw_softc *sc, enum rtw_pwrstate power)
{
        int rc;

        RTW_DPRINTF(RTW_DEBUG_PWR,
            ("%s: %s->%s\n", __func__,
            rtw_pwrstate_string(sc->sc_pwrstate), rtw_pwrstate_string(power)));

        if (sc->sc_pwrstate == power)
                return 0;

        rtw_pwrstate0(sc, power, 1, sc->sc_flags & RTW_F_DIGPHY);
        rc = rtw_rf_pwrstate(sc->sc_rf, power);
        rtw_pwrstate0(sc, power, 0, sc->sc_flags & RTW_F_DIGPHY);

        switch (power) {
        case RTW_ON:
                /* TBD set LEDs */
                break;
        case RTW_SLEEP:
                /* TBD */
                break;
        case RTW_OFF:
                /* TBD */
                break;
        }
        if (rc == 0)
                sc->sc_pwrstate = power;
        else
                sc->sc_pwrstate = RTW_OFF;
        return rc;
}

static int
rtw_tune(struct rtw_softc *sc)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct rtw_tx_radiotap_header *rt = &sc->sc_txtap;
        struct rtw_rx_radiotap_header *rr = &sc->sc_rxtap;
        u_int chan;
        int rc;
        int antdiv = sc->sc_flags & RTW_F_ANTDIV,
            dflantb = sc->sc_flags & RTW_F_DFLANTB;

        chan = ieee80211_chan2ieee(ic, ic->ic_curchan);
        KASSERT(chan != IEEE80211_CHAN_ANY);

        rt->rt_chan_freq = htole16(ic->ic_curchan->ic_freq);
        rt->rt_chan_flags = htole16(ic->ic_curchan->ic_flags);

        rr->rr_chan_freq = htole16(ic->ic_curchan->ic_freq);
        rr->rr_chan_flags = htole16(ic->ic_curchan->ic_flags);

        if (chan == sc->sc_cur_chan) {
                RTW_DPRINTF(RTW_DEBUG_TUNE,
                    ("%s: already tuned chan #%d\n", __func__, chan));
                return 0;
        }

        rtw_suspend_ticks(sc);

        rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 0);

        /* TBD wait for Tx to complete */

        KASSERT(device_has_power(sc->sc_dev));

        if ((rc = rtw_phy_init(&sc->sc_regs, sc->sc_rf,
            rtw_chan2txpower(&sc->sc_srom, ic, ic->ic_curchan), sc->sc_csthr,
                ic->ic_curchan->ic_freq, antdiv, dflantb, RTW_ON)) != 0) {
                /* XXX condition on powersaving */
                aprint_error_dev(sc->sc_dev, "phy init failed\n");
        }

        sc->sc_cur_chan = chan;

        rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 1);

        rtw_resume_ticks(sc);

        return rc;
}

bool
rtw_suspend(device_t self, const pmf_qual_t *qual)
{
        int rc;
        struct rtw_softc *sc = device_private(self);

        sc->sc_flags &= ~RTW_F_DK_VALID;

        if (!device_has_power(self))
                return false;

        /* turn off PHY */
        if ((rc = rtw_pwrstate(sc, RTW_OFF)) != 0) {
                aprint_error_dev(self, "failed to turn off PHY (%d)\n", rc);
                return false;
        }

        rtw_disable_interrupts(&sc->sc_regs);

        return true;
}

bool
rtw_resume(device_t self, const pmf_qual_t *qual)
{
        struct rtw_softc *sc = device_private(self);

        /* Power may have been removed, resetting WEP keys.
         */
        sc->sc_flags &= ~RTW_F_DK_VALID;
        rtw_enable_interrupts(sc);

        return true;
}

static void
rtw_transmit_config(struct rtw_regs *regs)
{
        uint32_t tcr;

        tcr = RTW_READ(regs, RTW_TCR);

        tcr |= RTW_TCR_CWMIN;
        tcr &= ~RTW_TCR_MXDMA_MASK;
        tcr |= RTW_TCR_MXDMA_256;
        tcr |= RTW_TCR_SAT;             /* send ACK as fast as possible */
        tcr &= ~RTW_TCR_LBK_MASK;
        tcr |= RTW_TCR_LBK_NORMAL;      /* normal operating mode */

        /* set short/long retry limits */
        tcr &= ~(RTW_TCR_SRL_MASK | RTW_TCR_LRL_MASK);
        tcr |= __SHIFTIN(4, RTW_TCR_SRL_MASK) | __SHIFTIN(4, RTW_TCR_LRL_MASK);

        tcr &= ~RTW_TCR_CRC;    /* NIC appends CRC32 */

        RTW_WRITE(regs, RTW_TCR, tcr);
        RTW_SYNC(regs, RTW_TCR, RTW_TCR);
}

static void
rtw_disable_interrupts(struct rtw_regs *regs)
{
        RTW_WRITE16(regs, RTW_IMR, 0);
        RTW_WBW(regs, RTW_IMR, RTW_ISR);
        RTW_WRITE16(regs, RTW_ISR, 0xffff);
        RTW_SYNC(regs, RTW_IMR, RTW_ISR);
}

static void
rtw_enable_interrupts(struct rtw_softc *sc)
{
        struct rtw_regs *regs = &sc->sc_regs;

        sc->sc_inten = RTW_INTR_RX | RTW_INTR_TX | RTW_INTR_BEACON
            | RTW_INTR_ATIMINT;
        sc->sc_inten |= RTW_INTR_IOERROR | RTW_INTR_TIMEOUT;

        RTW_WRITE16(regs, RTW_IMR, sc->sc_inten);
        RTW_WBW(regs, RTW_IMR, RTW_ISR);
        RTW_WRITE16(regs, RTW_ISR, 0xffff);
        RTW_SYNC(regs, RTW_IMR, RTW_ISR);

        /* XXX necessary? */
        if (sc->sc_intr_ack != NULL)
                (*sc->sc_intr_ack)(regs);
}

static void
rtw_set_nettype(struct rtw_softc *sc, enum ieee80211_opmode opmode)
{
        uint8_t msr;

        /* I'm guessing that MSR is protected as CONFIG[0123] are. */
        rtw_set_access(&sc->sc_regs, RTW_ACCESS_CONFIG);

        msr = RTW_READ8(&sc->sc_regs, RTW_MSR) & ~RTW_MSR_NETYPE_MASK;

        switch (opmode) {
        case IEEE80211_M_AHDEMO:
        case IEEE80211_M_IBSS:
                msr |= RTW_MSR_NETYPE_ADHOC_OK;
                break;
        case IEEE80211_M_HOSTAP:
                msr |= RTW_MSR_NETYPE_AP_OK;
                break;
        case IEEE80211_M_MONITOR:
                /* XXX */
                msr |= RTW_MSR_NETYPE_NOLINK;
                break;
        case IEEE80211_M_STA:
                msr |= RTW_MSR_NETYPE_INFRA_OK;
                break;
        }
        RTW_WRITE8(&sc->sc_regs, RTW_MSR, msr);

        rtw_set_access(&sc->sc_regs, RTW_ACCESS_NONE);
}

#define rtw_calchash(addr) \
        (ether_crc32_be((addr), IEEE80211_ADDR_LEN) >> 26)

static void
rtw_pktfilt_load(struct rtw_softc *sc)
{
        struct rtw_regs *regs = &sc->sc_regs;
        struct ieee80211com *ic = &sc->sc_ic;
        struct ethercom *ec = &sc->sc_ec;
        struct ifnet *ifp = &sc->sc_if;
        int hash;
        uint32_t hashes[2] = { 0, 0 };
        struct ether_multi *enm;
        struct ether_multistep step;

        /* XXX might be necessary to stop Rx/Tx engines while setting filters */

        sc->sc_rcr &= ~RTW_RCR_PKTFILTER_MASK;
        sc->sc_rcr &= ~(RTW_RCR_MXDMA_MASK | RTW_RCR_RXFTH_MASK);

        sc->sc_rcr |= RTW_RCR_PKTFILTER_DEFAULT;
        /* MAC auto-reset PHY (huh?) */
        sc->sc_rcr |= RTW_RCR_ENMARP;
        /* DMA whole Rx packets, only.  Set Tx DMA burst size to 1024 bytes. */
        sc->sc_rcr |= RTW_RCR_MXDMA_1024 | RTW_RCR_RXFTH_WHOLE;

        switch (ic->ic_opmode) {
        case IEEE80211_M_MONITOR:
                sc->sc_rcr |= RTW_RCR_MONITOR;
                break;
        case IEEE80211_M_AHDEMO:
        case IEEE80211_M_IBSS:
                /* receive broadcasts in our BSS */
                sc->sc_rcr |= RTW_RCR_ADD3;
                break;
        default:
                break;
        }

        ifp->if_flags &= ~IFF_ALLMULTI;

        /*
         * Program the 64-bit multicast hash filter.
         */
        ETHER_LOCK(ec);
        ETHER_FIRST_MULTI(step, ec, enm);
        while (enm != NULL) {
                /* XXX */
                if (memcmp(enm->enm_addrlo, enm->enm_addrhi,
                    ETHER_ADDR_LEN) != 0) {
                        ifp->if_flags |= IFF_ALLMULTI;
                        break;
                }

                hash = rtw_calchash(enm->enm_addrlo);
                hashes[hash >> 5] |= (1 << (hash & 0x1f));
                ETHER_NEXT_MULTI(step, enm);
        }
        ETHER_UNLOCK(ec);

        /* XXX accept all broadcast if scanning */
        if ((ifp->if_flags & IFF_BROADCAST) != 0)
                sc->sc_rcr |= RTW_RCR_AB;       /* accept all broadcast */

        if (ifp->if_flags & IFF_PROMISC) {
                sc->sc_rcr |= RTW_RCR_AB;       /* accept all broadcast */
                sc->sc_rcr |= RTW_RCR_ACRC32;   /* accept frames failing CRC */
                sc->sc_rcr |= RTW_RCR_AICV;     /* accept frames failing ICV */
                ifp->if_flags |= IFF_ALLMULTI;
        }

        if (ifp->if_flags & IFF_ALLMULTI)
                hashes[0] = hashes[1] = 0xffffffff;

        if ((hashes[0] | hashes[1]) != 0)
                sc->sc_rcr |= RTW_RCR_AM;       /* accept multicast */

        RTW_WRITE(regs, RTW_MAR0, hashes[0]);
        RTW_WRITE(regs, RTW_MAR1, hashes[1]);
        RTW_WRITE(regs, RTW_RCR, sc->sc_rcr);
        RTW_SYNC(regs, RTW_MAR0, RTW_RCR); /* RTW_MAR0 < RTW_MAR1 < RTW_RCR */

        DPRINTF(sc, RTW_DEBUG_PKTFILT,
            ("%s: RTW_MAR0 %08x RTW_MAR1 %08x RTW_RCR %08x\n",
            device_xname(sc->sc_dev), RTW_READ(regs, RTW_MAR0),
            RTW_READ(regs, RTW_MAR1), RTW_READ(regs, RTW_RCR)));
}

static struct mbuf *
rtw_beacon_alloc(struct rtw_softc *sc, struct ieee80211_node *ni)
{
        struct ieee80211com *ic = &sc->sc_ic;
        struct mbuf *m;
        struct ieee80211_beacon_offsets boff;

        if ((m = ieee80211_beacon_alloc(ic, ni, &boff)) != NULL) {
                RTW_DPRINTF(RTW_DEBUG_BEACON,
                    ("%s: m %p len %u\n", __func__, m, m->m_len));
        }
        return m;
}

/* Must be called at splnet. */
static int
rtw_init(struct ifnet *ifp)
{
        struct rtw_softc *sc = (struct rtw_softc *)ifp->if_softc;
        struct ieee80211com *ic = &sc->sc_ic;
        struct rtw_regs *regs = &sc->sc_regs;
        int rc;

        if (device_is_active(sc->sc_dev)) {
                /* Cancel pending I/O and reset. */
                rtw_stop(ifp, 0);
        } else if (!pmf_device_resume(sc->sc_dev, &sc->sc_qual) ||
                   !device_is_active(sc->sc_dev))
                return 0;

        DPRINTF(sc, RTW_DEBUG_TUNE, ("%s: channel %d freq %d flags 0x%04x\n",
            __func__, ieee80211_chan2ieee(ic, ic->ic_curchan),
            ic->ic_curchan->ic_freq, ic->ic_curchan->ic_flags));

        if ((rc = rtw_pwrstate(sc, RTW_OFF)) != 0)
                goto out;

        if ((rc = rtw_swring_setup(sc)) != 0)
                goto out;

        rtw_transmit_config(regs);

        rtw_set_access(regs, RTW_ACCESS_CONFIG);

        RTW_WRITE8(regs, RTW_MSR, 0x0); /* no link */
        RTW_WBW(regs, RTW_MSR, RTW_BRSR);

        /* long PLCP header, 1Mb/2Mb basic rate */
        RTW_WRITE16(regs, RTW_BRSR, RTW_BRSR_MBR8180_2MBPS);
        RTW_SYNC(regs, RTW_BRSR, RTW_BRSR);

        rtw_set_access(regs, RTW_ACCESS_ANAPARM);
        rtw_set_access(regs, RTW_ACCESS_NONE);

        /* XXX from reference sources */
        RTW_WRITE(regs, RTW_FEMR, 0xffff);
        RTW_SYNC(regs, RTW_FEMR, RTW_FEMR);

        rtw_set_rfprog(regs, sc->sc_rfchipid, sc->sc_dev);

        RTW_WRITE8(regs, RTW_PHYDELAY, sc->sc_phydelay);
        /* from Linux driver */
        RTW_WRITE8(regs, RTW_CRCOUNT, RTW_CRCOUNT_MAGIC);

        RTW_SYNC(regs, RTW_PHYDELAY, RTW_CRCOUNT);

        rtw_enable_interrupts(sc);

        rtw_pktfilt_load(sc);

        rtw_hwring_setup(sc);

        rtw_wep_setkeys(sc, ic->ic_nw_keys, ic->ic_def_txkey);

        rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 1);

        ifp->if_flags |= IFF_RUNNING;
        ic->ic_state = IEEE80211_S_INIT;

        RTW_WRITE16(regs, RTW_BSSID16, 0x0);
        RTW_WRITE(regs, RTW_BSSID32, 0x0);

        rtw_resume_ticks(sc);

        rtw_set_nettype(sc, IEEE80211_M_MONITOR);

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

out:
        aprint_error_dev(sc->sc_dev, "interface not running\n");
        return rc;
}

static inline void
rtw_led_init(struct rtw_regs *regs)
{
        uint8_t cfg0, cfg1;

        rtw_set_access(regs, RTW_ACCESS_CONFIG);

        cfg0 = RTW_READ8(regs, RTW_CONFIG0);
        cfg0 |= RTW_CONFIG0_LEDGPOEN;
        RTW_WRITE8(regs, RTW_CONFIG0, cfg0);

        cfg1 = RTW_READ8(regs, RTW_CONFIG1);
        RTW_DPRINTF(RTW_DEBUG_LED,
            ("%s: read %" PRIx8 " from reg[CONFIG1]\n", __func__, cfg1));

        cfg1 &= ~RTW_CONFIG1_LEDS_MASK;
        cfg1 |= RTW_CONFIG1_LEDS_TX_RX;
        RTW_WRITE8(regs, RTW_CONFIG1, cfg1);

        rtw_set_access(regs, RTW_ACCESS_NONE);
}

/*
 * IEEE80211_S_INIT:            LED1 off
 *
 * IEEE80211_S_AUTH,
 * IEEE80211_S_ASSOC,
 * IEEE80211_S_SCAN:            LED1 blinks @ 1 Hz, blinks at 5Hz for tx/rx
 *
 * IEEE80211_S_RUN:             LED1 on, blinks @ 5Hz for tx/rx
 */
static void
rtw_led_newstate(struct rtw_softc *sc, enum ieee80211_state nstate)
{
        struct rtw_led_state *ls;

        ls = &sc->sc_led_state;

        switch (nstate) {
        case IEEE80211_S_INIT:
                rtw_led_init(&sc->sc_regs);
                aprint_debug_dev(sc->sc_dev, "stopping blink\n");
                callout_stop(&ls->ls_slow_ch);
                callout_stop(&ls->ls_fast_ch);
                ls->ls_slowblink = 0;
                ls->ls_actblink = 0;
                ls->ls_default = 0;
                break;
        case IEEE80211_S_SCAN:
                aprint_debug_dev(sc->sc_dev, "scheduling blink\n");
                callout_schedule(&ls->ls_slow_ch, RTW_LED_SLOW_TICKS);
                callout_schedule(&ls->ls_fast_ch, RTW_LED_FAST_TICKS);
                /*FALLTHROUGH*/
        case IEEE80211_S_AUTH:
        case IEEE80211_S_ASSOC:
                ls->ls_default = RTW_LED1;
                ls->ls_actblink = RTW_LED1;
                ls->ls_slowblink = RTW_LED1;
                break;
        case IEEE80211_S_RUN:
                ls->ls_slowblink = 0;
                break;
        }
        rtw_led_set(ls, &sc->sc_regs, sc->sc_hwverid);
}

static void
rtw_led_set(struct rtw_led_state *ls, struct rtw_regs *regs, int hwverid)
{
        uint8_t led_condition;
        bus_size_t ofs;
        uint8_t mask, newval, val;

        led_condition = ls->ls_default;

        if (ls->ls_state & RTW_LED_S_SLOW)
                led_condition ^= ls->ls_slowblink;
        if (ls->ls_state & (RTW_LED_S_RX | RTW_LED_S_TX))
                led_condition ^= ls->ls_actblink;

        RTW_DPRINTF(RTW_DEBUG_LED,
            ("%s: LED condition %" PRIx8 "\n", __func__, led_condition));

        switch (hwverid) {
        default:
        case 'F':
                ofs = RTW_PSR;
                newval = mask = RTW_PSR_LEDGPO0 | RTW_PSR_LEDGPO1;
                if (led_condition & RTW_LED0)
                        newval &= ~RTW_PSR_LEDGPO0;
                if (led_condition & RTW_LED1)
                        newval &= ~RTW_PSR_LEDGPO1;
                break;
        case 'D':
                ofs = RTW_9346CR;
                mask = RTW_9346CR_EEM_MASK | RTW_9346CR_EEDI | RTW_9346CR_EECS;
                newval = RTW_9346CR_EEM_PROGRAM;
                if (led_condition & RTW_LED0)
                        newval |= RTW_9346CR_EEDI;
                if (led_condition & RTW_LED1)
                        newval |= RTW_9346CR_EECS;
                break;
        }
        val = RTW_READ8(regs, ofs);
        RTW_DPRINTF(RTW_DEBUG_LED,
            ("%s: read %" PRIx8 " from reg[%#02" PRIxPTR "]\n", __func__, val,
             (uintptr_t)ofs));
        val &= ~mask;
        val |= newval;
        RTW_WRITE8(regs, ofs, val);
        RTW_DPRINTF(RTW_DEBUG_LED,
            ("%s: wrote %" PRIx8 " to reg[%#02" PRIxPTR "]\n", __func__, val,
             (uintptr_t)ofs));
        RTW_SYNC(regs, ofs, ofs);
}

static void
rtw_led_fastblink(void *arg)
{
        int ostate, s;
        struct rtw_softc *sc = (struct rtw_softc *)arg;
        struct rtw_led_state *ls = &sc->sc_led_state;

        s = splnet();
        ostate = ls->ls_state;
        ls->ls_state ^= ls->ls_event;

        if ((ls->ls_event & RTW_LED_S_TX) == 0)
                ls->ls_state &= ~RTW_LED_S_TX;

        if ((ls->ls_event & RTW_LED_S_RX) == 0)
                ls->ls_state &= ~RTW_LED_S_RX;

        ls->ls_event = 0;

        if (ostate != ls->ls_state)
                rtw_led_set(ls, &sc->sc_regs, sc->sc_hwverid);
        splx(s);

        aprint_debug_dev(sc->sc_dev, "scheduling fast blink\n");
        callout_schedule(&ls->ls_fast_ch, RTW_LED_FAST_TICKS);
}

static void
rtw_led_slowblink(void *arg)
{
        int s;
        struct rtw_softc *sc = (struct rtw_softc *)arg;
        struct rtw_led_state *ls = &sc->sc_led_state;

        s = splnet();
        ls->ls_state ^= RTW_LED_S_SLOW;
        rtw_led_set(ls, &sc->sc_regs, sc->sc_hwverid);
        splx(s);
        aprint_debug_dev(sc->sc_dev, "scheduling slow blink\n");
        callout_schedule(&ls->ls_slow_ch, RTW_LED_SLOW_TICKS);
}

static void
rtw_led_detach(struct rtw_led_state *ls)
{
        callout_destroy(&ls->ls_fast_ch);
        callout_destroy(&ls->ls_slow_ch);
}

static void
rtw_led_attach(struct rtw_led_state *ls, void *arg)
{
        callout_init(&ls->ls_fast_ch, 0);
        callout_init(&ls->ls_slow_ch, 0);
        callout_setfunc(&ls->ls_fast_ch, rtw_led_fastblink, arg);
        callout_setfunc(&ls->ls_slow_ch, rtw_led_slowblink, arg);
}

static int
rtw_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
        int rc = 0, s;
        struct rtw_softc *sc = ifp->if_softc;

        s = splnet();
        if (cmd == SIOCSIFFLAGS) {
                if ((rc = ifioctl_common(ifp, cmd, data)) != 0)
                        ;
                else switch (ifp->if_flags & (IFF_UP | IFF_RUNNING)) {
                case IFF_UP:
                        rc = rtw_init(ifp);
                        RTW_PRINT_REGS(&sc->sc_regs, ifp->if_xname, __func__);
                        break;
                case IFF_UP | IFF_RUNNING:
                        if (device_activation(sc->sc_dev, DEVACT_LEVEL_DRIVER))
                                rtw_pktfilt_load(sc);
                        RTW_PRINT_REGS(&sc->sc_regs, ifp->if_xname, __func__);
                        break;
                case IFF_RUNNING:
                        RTW_PRINT_REGS(&sc->sc_regs, ifp->if_xname, __func__);
                        rtw_stop(ifp, 1);
                        break;
                default:
                        break;
                }
        } else if ((rc = ieee80211_ioctl(&sc->sc_ic, cmd, data)) != ENETRESET)
                ;       /* nothing to do */
        else if (cmd == SIOCADDMULTI || cmd == SIOCDELMULTI) {
                /* reload packet filter if running */
                if (ifp->if_flags & IFF_RUNNING)
                        rtw_pktfilt_load(sc);
                rc = 0;
        } else if ((ifp->if_flags & IFF_UP) != 0)
                rc = rtw_init(ifp);
        else
                rc = 0;
        splx(s);
        return rc;
}

/* Select a transmit ring with at least one h/w and s/w descriptor free.
 * Return 0 on success, -1 on failure.
 */
static inline int
rtw_txring_choose(struct rtw_softc *sc, struct rtw_txsoft_blk **tsbp,
    struct rtw_txdesc_blk **tdbp, int pri)
{
        struct rtw_txsoft_blk *tsb;
        struct rtw_txdesc_blk *tdb;

        KASSERT(pri >= 0 && pri < RTW_NTXPRI);

        tsb = &sc->sc_txsoft_blk[pri];
        tdb = &sc->sc_txdesc_blk[pri];

        if (SIMPLEQ_EMPTY(&tsb->tsb_freeq) || tdb->tdb_nfree == 0) {
                if (tsb->tsb_tx_timer == 0)
                        tsb->tsb_tx_timer = 5;
                *tsbp = NULL;
                *tdbp = NULL;
                return -1;
        }
        *tsbp = tsb;
        *tdbp = tdb;
        return 0;
}

static inline struct mbuf *
rtw_80211_dequeue(struct rtw_softc *sc, struct ifqueue *ifq, int pri,
    struct rtw_txsoft_blk **tsbp, struct rtw_txdesc_blk **tdbp,
    struct ieee80211_node **nip, short *if_flagsp)
{
        struct mbuf *m;

        if (IF_IS_EMPTY(ifq))
                return NULL;
        if (rtw_txring_choose(sc, tsbp, tdbp, pri) == -1) {
                DPRINTF(sc, RTW_DEBUG_XMIT_RSRC, ("%s: no ring %d descriptor\n",
                    __func__, pri));
                *if_flagsp |= IFF_OACTIVE;
                sc->sc_if.if_timer = 1;
                return NULL;
        }
        IF_DEQUEUE(ifq, m);
        *nip = M_GETCTX(m, struct ieee80211_node *);
        M_SETCTX(m, NULL);
        KASSERT(*nip != NULL);
        return m;
}

/* Point *mp at the next 802.11 frame to transmit.  Point *tsbp
 * at the driver's selection of transmit control block for the packet.
 */
static inline int
rtw_dequeue(struct ifnet *ifp, struct rtw_txsoft_blk **tsbp,
    struct rtw_txdesc_blk **tdbp, struct mbuf **mp,
    struct ieee80211_node **nip)
{
        int pri;
        struct ether_header *eh;
        struct mbuf *m0;
        struct rtw_softc *sc;
        short *if_flagsp;

        *mp = NULL;

        sc = (struct rtw_softc *)ifp->if_softc;

        DPRINTF(sc, RTW_DEBUG_XMIT,
            ("%s: enter %s\n", device_xname(sc->sc_dev), __func__));

        if_flagsp = &ifp->if_flags;

        if (sc->sc_ic.ic_state == IEEE80211_S_RUN &&
            (*mp = rtw_80211_dequeue(sc, &sc->sc_beaconq, RTW_TXPRIBCN, tsbp,
                                     tdbp, nip, if_flagsp)) != NULL) {
                DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: dequeue beacon frame\n",
                    __func__));
                return 0;
        }

        if ((*mp = rtw_80211_dequeue(sc, &sc->sc_ic.ic_mgtq, RTW_TXPRIMD, tsbp,
                                     tdbp, nip, if_flagsp)) != NULL) {
                DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: dequeue mgt frame\n",
                    __func__));
                return 0;
        }

        if (sc->sc_ic.ic_state != IEEE80211_S_RUN) {
                DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: not running\n", __func__));
                return 0;
        }

        IFQ_POLL(&ifp->if_snd, m0);
        if (m0 == NULL) {
                DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: no frame ready\n",
                    __func__));
                return 0;
        }

        pri = ((m0->m_flags & M_PWR_SAV) != 0) ? RTW_TXPRIHI : RTW_TXPRIMD;

        if (rtw_txring_choose(sc, tsbp, tdbp, pri) == -1) {
                DPRINTF(sc, RTW_DEBUG_XMIT_RSRC, ("%s: no ring %d descriptor\n",
                    __func__, pri));
                *if_flagsp |= IFF_OACTIVE;
                sc->sc_if.if_timer = 1;
                return 0;
        }

        IFQ_DEQUEUE(&ifp->if_snd, m0);
        if (m0 == NULL) {
                DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: no frame ready\n",
                    __func__));
                return 0;
        }
        DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: dequeue data frame\n", __func__));
        if_statinc(ifp, if_opackets);
        bpf_mtap(ifp, m0, BPF_D_OUT);
        eh = mtod(m0, struct ether_header *);
        *nip = ieee80211_find_txnode(&sc->sc_ic, eh->ether_dhost);
        if (*nip == NULL) {
                /* NB: ieee80211_find_txnode does stat+msg */
                m_freem(m0);
                return -1;
        }
        if ((m0 = ieee80211_encap(&sc->sc_ic, m0, *nip)) == NULL) {
                DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: encap error\n", __func__));
                if_statinc(ifp, if_oerrors);
                return -1;
        }
        DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: leave\n", __func__));
        *mp = m0;
        return 0;
}

static int
rtw_seg_too_short(bus_dmamap_t dmamap)
{
        int i;
        for (i = 0; i < dmamap->dm_nsegs; i++) {
                if (dmamap->dm_segs[i].ds_len < 4)
                        return 1;
        }
        return 0;
}

/* TBD factor with atw_start */
static struct mbuf *
rtw_dmamap_load_txbuf(bus_dma_tag_t dmat, bus_dmamap_t dmam, struct mbuf *chain,
    u_int ndescfree, device_t dev)
{
        int first, rc;
        struct mbuf *m, *m0;

        m0 = chain;

        /*
         * Load the DMA map.  Copy and try (once) again if the packet
         * didn't fit in the alloted number of segments.
         */
        for (first = 1;
             ((rc = bus_dmamap_load_mbuf(dmat, dmam, m0,
                          BUS_DMA_WRITE | BUS_DMA_NOWAIT)) != 0 ||
              dmam->dm_nsegs > ndescfree || rtw_seg_too_short(dmam)) && first;
             first = 0) {
                if (rc == 0) {
#ifdef RTW_DIAGxxx
                        if (rtw_seg_too_short(dmam)) {
                                printf("%s: short segment, mbuf lengths:", __func__);
                                for (m = m0; m; m = m->m_next)
                                        printf(" %d", m->m_len);
                                printf("\n");
                        }
#endif
                        bus_dmamap_unload(dmat, dmam);
                }
                MGETHDR(m, M_DONTWAIT, MT_DATA);
                if (m == NULL) {
                        aprint_error_dev(dev, "unable to allocate Tx mbuf\n");
                        break;
                }
                if (m0->m_pkthdr.len > MHLEN) {
                        MCLGET(m, M_DONTWAIT);
                        if ((m->m_flags & M_EXT) == 0) {
                                aprint_error_dev(dev,
                                    "cannot allocate Tx cluster\n");
                                m_freem(m);
                                break;
                        }
                }
                m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, void *));
                m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
                m_freem(m0);
                m0 = m;
                m = NULL;
        }
        if (rc != 0) {
                aprint_error_dev(dev, "cannot load Tx buffer, rc = %d\n", rc);
                m_freem(m0);
                return NULL;
        } else if (rtw_seg_too_short(dmam)) {
                aprint_error_dev(dev,
                    "cannot load Tx buffer, segment too short\n");
                bus_dmamap_unload(dmat, dmam);
                m_freem(m0);
                return NULL;
        } else if (dmam->dm_nsegs > ndescfree) {
                aprint_error_dev(dev, "too many tx segments\n");
                bus_dmamap_unload(dmat, dmam);
                m_freem(m0);
                return NULL;
        }
        return m0;
}

#ifdef RTW_DEBUG
static void
rtw_print_txdesc(struct rtw_softc *sc, const char *action,
    struct rtw_txsoft *ts, struct rtw_txdesc_blk *tdb, int desc)
{
        struct rtw_txdesc *td = &tdb->tdb_desc[desc];
        DPRINTF(sc, RTW_DEBUG_XMIT_DESC, ("%s: %p %s txdesc[%d] next %#08x "
            "buf %#08x ctl0 %#08x ctl1 %#08x len %#08x\n",
            device_xname(sc->sc_dev), ts, action, desc,
            le32toh(td->td_buf), le32toh(td->td_next),
            le32toh(td->td_ctl0), le32toh(td->td_ctl1),
            le32toh(td->td_len)));
}
#endif /* RTW_DEBUG */

static void
rtw_start(struct ifnet *ifp)
{
        int desc, i, lastdesc, npkt, rate;
        uint32_t proto_ctl0, ctl0, ctl1;
        bus_dmamap_t            dmamap;
        struct ieee80211com     *ic;
        struct ieee80211_duration *d0;
        struct ieee80211_frame_min      *wh;
        struct ieee80211_node   *ni = NULL;     /* XXX: GCC */
        struct mbuf             *m0;
        struct rtw_softc        *sc;
        struct rtw_txsoft_blk   *tsb = NULL;    /* XXX: GCC */
        struct rtw_txdesc_blk   *tdb = NULL;    /* XXX: GCC */
        struct rtw_txsoft       *ts;
        struct rtw_txdesc       *td;
        struct ieee80211_key    *k;

        sc = (struct rtw_softc *)ifp->if_softc;
        ic = &sc->sc_ic;

        DPRINTF(sc, RTW_DEBUG_XMIT,
            ("%s: enter %s\n", device_xname(sc->sc_dev), __func__));

        if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
                goto out;

        /* XXX do real rate control */
        proto_ctl0 = RTW_TXCTL0_RTSRATE_1MBPS;

        if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) != 0)
                proto_ctl0 |= RTW_TXCTL0_SPLCP;

        for (;;) {
                if (rtw_dequeue(ifp, &tsb, &tdb, &m0, &ni) == -1)
                        continue;
                if (m0 == NULL)
                        break;

                wh = mtod(m0, struct ieee80211_frame_min *);

                if ((wh->i_fc[1] & IEEE80211_FC1_WEP) != 0 &&
                    (k = ieee80211_crypto_encap(ic, ni, m0)) == NULL) {
                        m_freem(m0);
                        break;
                } else
                        k = NULL;

                ts = SIMPLEQ_FIRST(&tsb->tsb_freeq);

                dmamap = ts->ts_dmamap;

                m0 = rtw_dmamap_load_txbuf(sc->sc_dmat, dmamap, m0,
                    tdb->tdb_nfree, sc->sc_dev);

                if (m0 == NULL || dmamap->dm_nsegs == 0) {
                        DPRINTF(sc, RTW_DEBUG_XMIT,
                            ("%s: fail dmamap load\n", __func__));
                        goto post_dequeue_err;
                }

                /* Note well: rtw_dmamap_load_txbuf may have created
                 * a new chain, so we must find the header once
                 * more.
                 */
                wh = mtod(m0, struct ieee80211_frame_min *);

                /* XXX do real rate control */
                if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) ==
                    IEEE80211_FC0_TYPE_MGT)
                        rate = 2;
                else
                        rate = MAX(2, ieee80211_get_rate(ni));

#ifdef RTW_DEBUG
                if ((ifp->if_flags & (IFF_DEBUG | IFF_LINK2)) ==
                    (IFF_DEBUG | IFF_LINK2)) {
                        ieee80211_dump_pkt(mtod(m0, uint8_t *),
                            (dmamap->dm_nsegs == 1) ? m0->m_pkthdr.len
                                                    : sizeof(wh),
                            rate, 0);
                }
#endif /* RTW_DEBUG */
                ctl0 = proto_ctl0 |
                    __SHIFTIN(m0->m_pkthdr.len, RTW_TXCTL0_TPKTSIZE_MASK);

                switch (rate) {
                default:
                case 2:
                        ctl0 |= RTW_TXCTL0_RATE_1MBPS;
                        break;
                case 4:
                        ctl0 |= RTW_TXCTL0_RATE_2MBPS;
                        break;
                case 11:
                        ctl0 |= RTW_TXCTL0_RATE_5MBPS;
                        break;
                case 22:
                        ctl0 |= RTW_TXCTL0_RATE_11MBPS;
                        break;
                }
                /* XXX >= ? Compare after fragmentation? */
                if (m0->m_pkthdr.len > ic->ic_rtsthreshold)
                        ctl0 |= RTW_TXCTL0_RTSEN;

                /* XXX Sometimes writes a bogus keyid; h/w doesn't
                 * seem to care, since we don't activate h/w Tx
                 * encryption.
                 */
                if (k != NULL &&
                    k->wk_cipher->ic_cipher == IEEE80211_CIPHER_WEP) {
                        ctl0 |= __SHIFTIN(k->wk_keyix, RTW_TXCTL0_KEYID_MASK) &
                            RTW_TXCTL0_KEYID_MASK;
                }

                if ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) ==
                    IEEE80211_FC0_TYPE_MGT) {
                        ctl0 &= ~(RTW_TXCTL0_SPLCP | RTW_TXCTL0_RTSEN);
                        if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) ==
                            IEEE80211_FC0_SUBTYPE_BEACON)
                                ctl0 |= RTW_TXCTL0_BEACON;
                }

                if (ieee80211_compute_duration(wh, k, m0->m_pkthdr.len,
                    ic->ic_flags, ic->ic_fragthreshold,
                    rate, &ts->ts_d0, &ts->ts_dn, &npkt,
                    (ifp->if_flags & (IFF_DEBUG | IFF_LINK2)) ==
                    (IFF_DEBUG | IFF_LINK2)) == -1) {
                        DPRINTF(sc, RTW_DEBUG_XMIT,
                            ("%s: fail compute duration\n", __func__));
                        goto post_load_err;
                }

                d0 = &ts->ts_d0;

                *(uint16_t*)wh->i_dur = htole16(d0->d_data_dur);

                ctl1 = __SHIFTIN(d0->d_plcp_len, RTW_TXCTL1_LENGTH_MASK) |
                    __SHIFTIN(d0->d_rts_dur, RTW_TXCTL1_RTSDUR_MASK);

                if (d0->d_residue)
                        ctl1 |= RTW_TXCTL1_LENGEXT;

                /* TBD fragmentation */

                ts->ts_first = tdb->tdb_next;

                rtw_txdescs_sync(tdb, ts->ts_first, dmamap->dm_nsegs,
                    BUS_DMASYNC_PREWRITE);

                KASSERT(ts->ts_first < tdb->tdb_ndesc);

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

                if (sc->sc_radiobpf != NULL) {
                        struct rtw_tx_radiotap_header *rt = &sc->sc_txtap;

                        rt->rt_rate = rate;

                        bpf_mtap2(sc->sc_radiobpf, rt, sizeof(sc->sc_txtapu),
                            m0, BPF_D_OUT);
                }

                for (i = 0, lastdesc = desc = ts->ts_first;
                     i < dmamap->dm_nsegs;
                     i++, desc = RTW_NEXT_IDX(tdb, desc)) {
                        if (dmamap->dm_segs[i].ds_len > RTW_TXLEN_LENGTH_MASK) {
                                DPRINTF(sc, RTW_DEBUG_XMIT_DESC,
                                    ("%s: seg too long\n", __func__));
                                goto post_load_err;
                        }
                        td = &tdb->tdb_desc[desc];
                        td->td_ctl0 = htole32(ctl0);
                        td->td_ctl1 = htole32(ctl1);
                        td->td_buf = htole32(dmamap->dm_segs[i].ds_addr);
                        td->td_len = htole32(dmamap->dm_segs[i].ds_len);
                        td->td_next = htole32(RTW_NEXT_DESC(tdb, desc));
                        if (i != 0)
                                td->td_ctl0 |= htole32(RTW_TXCTL0_OWN);
                        lastdesc = desc;
#ifdef RTW_DEBUG
                        rtw_print_txdesc(sc, "load", ts, tdb, desc);
#endif /* RTW_DEBUG */
                }

                KASSERT(desc < tdb->tdb_ndesc);

                ts->ts_ni = ni;
                KASSERT(ni != NULL);
                ts->ts_mbuf = m0;
                ts->ts_last = lastdesc;
                tdb->tdb_desc[ts->ts_last].td_ctl0 |= htole32(RTW_TXCTL0_LS);
                tdb->tdb_desc[ts->ts_first].td_ctl0 |=
                   htole32(RTW_TXCTL0_FS);

#ifdef RTW_DEBUG
                rtw_print_txdesc(sc, "FS on", ts, tdb, ts->ts_first);
                rtw_print_txdesc(sc, "LS on", ts, tdb, ts->ts_last);
#endif /* RTW_DEBUG */

                tdb->tdb_nfree -= dmamap->dm_nsegs;
                tdb->tdb_next = desc;

                rtw_txdescs_sync(tdb, ts->ts_first, dmamap->dm_nsegs,
                    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

                tdb->tdb_desc[ts->ts_first].td_ctl0 |=
                    htole32(RTW_TXCTL0_OWN);

#ifdef RTW_DEBUG
                rtw_print_txdesc(sc, "OWN on", ts, tdb, ts->ts_first);
#endif /* RTW_DEBUG */

                rtw_txdescs_sync(tdb, ts->ts_first, 1,
                    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

                SIMPLEQ_REMOVE_HEAD(&tsb->tsb_freeq, ts_q);
                SIMPLEQ_INSERT_TAIL(&tsb->tsb_dirtyq, ts, ts_q);

                if (tsb != &sc->sc_txsoft_blk[RTW_TXPRIBCN])
                        sc->sc_led_state.ls_event |= RTW_LED_S_TX;
                tsb->tsb_tx_timer = 5;
                ifp->if_timer = 1;
                rtw_tx_kick(&sc->sc_regs, tsb->tsb_poll);
        }
out:
        DPRINTF(sc, RTW_DEBUG_XMIT, ("%s: leave\n", __func__));
        return;
post_load_err:
        bus_dmamap_unload(sc->sc_dmat, dmamap);
        m_freem(m0);
post_dequeue_err:
        ieee80211_free_node(ni);
        return;
}

static void
rtw_idle(struct rtw_regs *regs)
{
        int active;
        uint8_t tppoll;

        /* request stop DMA; wait for packets to stop transmitting. */

        RTW_WRITE8(regs, RTW_TPPOLL, RTW_TPPOLL_SALL);
        RTW_WBR(regs, RTW_TPPOLL, RTW_TPPOLL);

        for (active = 0; active < 300 &&
             (tppoll = RTW_READ8(regs, RTW_TPPOLL) & RTW_TPPOLL_ACTIVE) != 0;
             active++)
                DELAY(10);
        printf("%s: transmit DMA idle in %dus, tppoll %02" PRIx8 "\n", __func__,
            active * 10, tppoll);
}

static void
rtw_watchdog(struct ifnet *ifp)
{
        int pri, tx_timeouts = 0;
        struct rtw_softc *sc;
        struct rtw_txsoft_blk *tsb;

        sc = ifp->if_softc;

        ifp->if_timer = 0;

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

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tsb = &sc->sc_txsoft_blk[pri];

                if (tsb->tsb_tx_timer == 0)
                        continue;
                else if (--tsb->tsb_tx_timer == 0) {
                        if (SIMPLEQ_EMPTY(&tsb->tsb_dirtyq))
                                continue;
                        else if (rtw_collect_txring(sc, tsb,
                            &sc->sc_txdesc_blk[pri], 0))
                                continue;
                        printf("%s: transmit timeout, priority %d\n",
                            ifp->if_xname, pri);
                        if_statinc(ifp, if_oerrors);
                        if (pri != RTW_TXPRIBCN)
                                tx_timeouts++;
                } else
                        ifp->if_timer = 1;
        }

        if (tx_timeouts > 0) {
                /* Stop Tx DMA, disable xmtr, flush Tx rings, enable xmtr,
                 * reset s/w tx-ring pointers, and start transmission.
                 *
                 * TBD Stop/restart just the broken rings?
                 */
                rtw_idle(&sc->sc_regs);
                rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 0);
                rtw_txdescs_reset(sc);
                rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 1);
                rtw_start(ifp);
        }
        ieee80211_watchdog(&sc->sc_ic);
        return;
}

static void
rtw_next_scan(void *arg)
{
        struct ieee80211com *ic = arg;
        int s;

        /* don't call rtw_start w/o network interrupts blocked */
        s = splnet();
        if (ic->ic_state == IEEE80211_S_SCAN)
                ieee80211_next_scan(ic);
        splx(s);
}

static void
rtw_join_bss(struct rtw_softc *sc, uint8_t *bssid, uint16_t intval0)
{
        uint16_t bcnitv, bintritv, intval;
        int i;
        struct rtw_regs *regs = &sc->sc_regs;

        for (i = 0; i < IEEE80211_ADDR_LEN; i++)
                RTW_WRITE8(regs, RTW_BSSID + i, bssid[i]);

        RTW_SYNC(regs, RTW_BSSID16, RTW_BSSID32);

        rtw_set_access(regs, RTW_ACCESS_CONFIG);

        intval = MIN(intval0, __SHIFTOUT_MASK(RTW_BCNITV_BCNITV_MASK));

        bcnitv = RTW_READ16(regs, RTW_BCNITV) & ~RTW_BCNITV_BCNITV_MASK;
        bcnitv |= __SHIFTIN(intval, RTW_BCNITV_BCNITV_MASK);
        RTW_WRITE16(regs, RTW_BCNITV, bcnitv);
        /* interrupt host 1ms before the TBTT */
        bintritv = RTW_READ16(regs, RTW_BINTRITV) & ~RTW_BINTRITV_BINTRITV;
        bintritv |= __SHIFTIN(1000, RTW_BINTRITV_BINTRITV);
        RTW_WRITE16(regs, RTW_BINTRITV, bintritv);
        /* magic from Linux */
        RTW_WRITE16(regs, RTW_ATIMWND, __SHIFTIN(1, RTW_ATIMWND_ATIMWND));
        RTW_WRITE16(regs, RTW_ATIMTRITV, __SHIFTIN(2, RTW_ATIMTRITV_ATIMTRITV));
        rtw_set_access(regs, RTW_ACCESS_NONE);

        rtw_io_enable(sc, RTW_CR_RE | RTW_CR_TE, 1);
}

/* Synchronize the hardware state with the software state. */
static int
rtw_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int arg)
{
        struct ifnet *ifp = ic->ic_ifp;
        struct rtw_softc *sc = (struct rtw_softc *)ifp->if_softc;
        enum ieee80211_state ostate;
        int error;

        ostate = ic->ic_state;

        aprint_debug_dev(sc->sc_dev, "%s: l.%d\n", __func__, __LINE__);
        rtw_led_newstate(sc, nstate);

        aprint_debug_dev(sc->sc_dev, "%s: l.%d\n", __func__, __LINE__);
        if (nstate == IEEE80211_S_INIT) {
                callout_stop(&sc->sc_scan_ch);
                sc->sc_cur_chan = IEEE80211_CHAN_ANY;
                return (*sc->sc_mtbl.mt_newstate)(ic, nstate, arg);
        }

        if (ostate == IEEE80211_S_INIT && nstate != IEEE80211_S_INIT)
                rtw_pwrstate(sc, RTW_ON);

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

        switch (nstate) {
        case IEEE80211_S_INIT:
                panic("%s: unexpected state IEEE80211_S_INIT\n", __func__);
                break;
        case IEEE80211_S_SCAN:
                if (ostate != IEEE80211_S_SCAN) {
                        (void)memset(ic->ic_bss->ni_bssid, 0,
                            IEEE80211_ADDR_LEN);
                        rtw_set_nettype(sc, IEEE80211_M_MONITOR);
                }

                callout_reset(&sc->sc_scan_ch, rtw_dwelltime * hz / 1000,
                    rtw_next_scan, ic);

                break;
        case IEEE80211_S_RUN:
                switch (ic->ic_opmode) {
                case IEEE80211_M_HOSTAP:
                case IEEE80211_M_IBSS:
                        rtw_set_nettype(sc, IEEE80211_M_MONITOR);
                        /*FALLTHROUGH*/
                case IEEE80211_M_AHDEMO:
                case IEEE80211_M_STA:
                        rtw_join_bss(sc, ic->ic_bss->ni_bssid,
                            ic->ic_bss->ni_intval);
                        break;
                case IEEE80211_M_MONITOR:
                        break;
                }
                rtw_set_nettype(sc, ic->ic_opmode);
                break;
        case IEEE80211_S_ASSOC:
        case IEEE80211_S_AUTH:
                break;
        }

        if (nstate != IEEE80211_S_SCAN)
                callout_stop(&sc->sc_scan_ch);

        return (*sc->sc_mtbl.mt_newstate)(ic, nstate, arg);
}

/* Extend a 32-bit TSF timestamp to a 64-bit timestamp. */
static uint64_t
rtw_tsf_extend(struct rtw_regs *regs, uint32_t rstamp)
{
        uint32_t tsftl, tsfth;

        tsfth = RTW_READ(regs, RTW_TSFTRH);
        tsftl = RTW_READ(regs, RTW_TSFTRL);
        if (tsftl < rstamp)     /* Compensate for rollover. */
                tsfth--;
        return ((uint64_t)tsfth << 32) | rstamp;
}

static void
rtw_recv_mgmt(struct ieee80211com *ic, struct mbuf *m,
    struct ieee80211_node *ni, int subtype, int rssi, uint32_t rstamp)
{
        struct ifnet *ifp = ic->ic_ifp;
        struct rtw_softc *sc = (struct rtw_softc *)ifp->if_softc;

        (*sc->sc_mtbl.mt_recv_mgmt)(ic, m, ni, subtype, rssi, rstamp);

        switch (subtype) {
        case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
        case IEEE80211_FC0_SUBTYPE_BEACON:
                if (ic->ic_opmode == IEEE80211_M_IBSS &&
                    ic->ic_state == IEEE80211_S_RUN &&
                    device_is_active(sc->sc_dev)) {
                        uint64_t tsf = rtw_tsf_extend(&sc->sc_regs, rstamp);
                        if (le64toh(ni->ni_tstamp.tsf) >= tsf)
                                (void)ieee80211_ibss_merge(ni);
                }
                break;
        default:
                break;
        }
        return;
}

static struct ieee80211_node *
rtw_node_alloc(struct ieee80211_node_table *nt)
{
        struct ifnet *ifp = nt->nt_ic->ic_ifp;
        struct rtw_softc *sc = (struct rtw_softc *)ifp->if_softc;
        struct ieee80211_node *ni = (*sc->sc_mtbl.mt_node_alloc)(nt);

        DPRINTF(sc, RTW_DEBUG_NODE,
            ("%s: alloc node %p\n", device_xname(sc->sc_dev), ni));
        return ni;
}

static void
rtw_node_free(struct ieee80211_node *ni)
{
        struct ieee80211com *ic = ni->ni_ic;
        struct ifnet *ifp = ic->ic_ifp;
        struct rtw_softc *sc = (struct rtw_softc *)ifp->if_softc;

        DPRINTF(sc, RTW_DEBUG_NODE,
            ("%s: freeing node %p %s\n", device_xname(sc->sc_dev), ni,
            ether_sprintf(ni->ni_bssid)));
        (*sc->sc_mtbl.mt_node_free)(ni);
}

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

        error = ieee80211_media_change(ifp);
        if (error == ENETRESET) {
                if ((ifp->if_flags & (IFF_RUNNING | IFF_UP)) ==
                    (IFF_RUNNING | IFF_UP))
                        rtw_init(ifp);          /* XXX lose error */
                error = 0;
        }
        return error;
}

static void
rtw_media_status(struct ifnet *ifp, struct ifmediareq *imr)
{
        struct rtw_softc *sc = ifp->if_softc;

        if (!device_is_active(sc->sc_dev)) {
                imr->ifm_active = IFM_IEEE80211 | IFM_NONE;
                imr->ifm_status = 0;
                return;
        }
        ieee80211_media_status(ifp, imr);
}

static inline void
rtw_setifprops(struct ifnet *ifp, const char *dvname, void *softc)
{
        (void)strlcpy(ifp->if_xname, dvname, IFNAMSIZ);
        ifp->if_softc = softc;
        ifp->if_flags = IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST;
        ifp->if_ioctl = rtw_ioctl;
        ifp->if_start = rtw_start;
        ifp->if_watchdog = rtw_watchdog;
        ifp->if_init = rtw_init;
        ifp->if_stop = rtw_stop;
}

static inline void
rtw_set80211props(struct ieee80211com *ic)
{
        int nrate;
        ic->ic_phytype = IEEE80211_T_DS;
        ic->ic_opmode = IEEE80211_M_STA;
        ic->ic_caps = IEEE80211_C_PMGT | IEEE80211_C_IBSS |
            IEEE80211_C_HOSTAP | IEEE80211_C_MONITOR | IEEE80211_C_WEP;

        nrate = 0;
        ic->ic_sup_rates[IEEE80211_MODE_11B].rs_rates[nrate++] =
            IEEE80211_RATE_BASIC | 2;
        ic->ic_sup_rates[IEEE80211_MODE_11B].rs_rates[nrate++] =
            IEEE80211_RATE_BASIC | 4;
        ic->ic_sup_rates[IEEE80211_MODE_11B].rs_rates[nrate++] = 11;
        ic->ic_sup_rates[IEEE80211_MODE_11B].rs_rates[nrate++] = 22;
        ic->ic_sup_rates[IEEE80211_MODE_11B].rs_nrates = nrate;
}

static inline void
rtw_set80211methods(struct rtw_mtbl *mtbl, struct ieee80211com *ic)
{
        mtbl->mt_newstate = ic->ic_newstate;
        ic->ic_newstate = rtw_newstate;

        mtbl->mt_recv_mgmt = ic->ic_recv_mgmt;
        ic->ic_recv_mgmt = rtw_recv_mgmt;

        mtbl->mt_node_free = ic->ic_node_free;
        ic->ic_node_free = rtw_node_free;

        mtbl->mt_node_alloc = ic->ic_node_alloc;
        ic->ic_node_alloc = rtw_node_alloc;

        ic->ic_crypto.cs_key_delete = rtw_key_delete;
        ic->ic_crypto.cs_key_set = rtw_key_set;
        ic->ic_crypto.cs_key_update_begin = rtw_key_update_begin;
        ic->ic_crypto.cs_key_update_end = rtw_key_update_end;
}

static inline void
rtw_init_radiotap(struct rtw_softc *sc)
{
        uint32_t present;

        memset(&sc->sc_rxtapu, 0, sizeof(sc->sc_rxtapu));
        sc->sc_rxtap.rr_ihdr.it_len = htole16(sizeof(sc->sc_rxtapu));

        if (sc->sc_rfchipid == RTW_RFCHIPID_PHILIPS)
                present = htole32(RTW_PHILIPS_RX_RADIOTAP_PRESENT);
        else
                present = htole32(RTW_RX_RADIOTAP_PRESENT);
        sc->sc_rxtap.rr_ihdr.it_present = present;

        memset(&sc->sc_txtapu, 0, sizeof(sc->sc_txtapu));
        sc->sc_txtap.rt_ihdr.it_len = htole16(sizeof(sc->sc_txtapu));
        sc->sc_txtap.rt_ihdr.it_present = htole32(RTW_TX_RADIOTAP_PRESENT);
}

static int
rtw_txsoft_blk_setup(struct rtw_txsoft_blk *tsb, u_int qlen)
{
        SIMPLEQ_INIT(&tsb->tsb_dirtyq);
        SIMPLEQ_INIT(&tsb->tsb_freeq);
        tsb->tsb_ndesc = qlen;
        tsb->tsb_desc = malloc(qlen * sizeof(*tsb->tsb_desc), M_DEVBUF,
            M_WAITOK);
        return 0;
}

static void
rtw_txsoft_blk_cleanup_all(struct rtw_softc *sc)
{
        int pri;
        struct rtw_txsoft_blk *tsb;

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tsb = &sc->sc_txsoft_blk[pri];
                free(tsb->tsb_desc, M_DEVBUF);
                tsb->tsb_desc = NULL;
        }
}

static int
rtw_txsoft_blk_setup_all(struct rtw_softc *sc)
{
        int pri, rc = 0;
        int qlen[RTW_NTXPRI] =
             {RTW_TXQLENLO, RTW_TXQLENMD, RTW_TXQLENHI, RTW_TXQLENBCN};
        struct rtw_txsoft_blk *tsbs;

        tsbs = sc->sc_txsoft_blk;

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                rc = rtw_txsoft_blk_setup(&tsbs[pri], qlen[pri]);
                if (rc != 0)
                        break;
        }
        tsbs[RTW_TXPRILO].tsb_poll = RTW_TPPOLL_LPQ | RTW_TPPOLL_SLPQ;
        tsbs[RTW_TXPRIMD].tsb_poll = RTW_TPPOLL_NPQ | RTW_TPPOLL_SNPQ;
        tsbs[RTW_TXPRIHI].tsb_poll = RTW_TPPOLL_HPQ | RTW_TPPOLL_SHPQ;
        tsbs[RTW_TXPRIBCN].tsb_poll = RTW_TPPOLL_BQ | RTW_TPPOLL_SBQ;
        return rc;
}

static void
rtw_txdesc_blk_setup(struct rtw_txdesc_blk *tdb, struct rtw_txdesc *desc,
    u_int ndesc, bus_addr_t ofs, bus_addr_t physbase)
{
        tdb->tdb_ndesc = ndesc;
        tdb->tdb_desc = desc;
        tdb->tdb_physbase = physbase;
        tdb->tdb_ofs = ofs;

        (void)memset(tdb->tdb_desc, 0,
            sizeof(tdb->tdb_desc[0]) * tdb->tdb_ndesc);

        rtw_txdesc_blk_init(tdb);
        tdb->tdb_next = 0;
}

static void
rtw_txdesc_blk_setup_all(struct rtw_softc *sc)
{
        rtw_txdesc_blk_setup(&sc->sc_txdesc_blk[RTW_TXPRILO],
            &sc->sc_descs->hd_txlo[0], RTW_NTXDESCLO,
            RTW_RING_OFFSET(hd_txlo), RTW_RING_BASE(sc, hd_txlo));

        rtw_txdesc_blk_setup(&sc->sc_txdesc_blk[RTW_TXPRIMD],
            &sc->sc_descs->hd_txmd[0], RTW_NTXDESCMD,
            RTW_RING_OFFSET(hd_txmd), RTW_RING_BASE(sc, hd_txmd));

        rtw_txdesc_blk_setup(&sc->sc_txdesc_blk[RTW_TXPRIHI],
            &sc->sc_descs->hd_txhi[0], RTW_NTXDESCHI,
            RTW_RING_OFFSET(hd_txhi), RTW_RING_BASE(sc, hd_txhi));

        rtw_txdesc_blk_setup(&sc->sc_txdesc_blk[RTW_TXPRIBCN],
            &sc->sc_descs->hd_bcn[0], RTW_NTXDESCBCN,
            RTW_RING_OFFSET(hd_bcn), RTW_RING_BASE(sc, hd_bcn));
}

static struct rtw_rf *
rtw_rf_attach(struct rtw_softc *sc, enum rtw_rfchipid rfchipid, int digphy)
{
        rtw_rf_write_t rf_write;
        struct rtw_rf *rf;

        switch (rfchipid) {
        default:
                rf_write = rtw_rf_hostwrite;
                break;
        case RTW_RFCHIPID_INTERSIL:
        case RTW_RFCHIPID_PHILIPS:
        case RTW_RFCHIPID_GCT:  /* XXX a guess */
        case RTW_RFCHIPID_RFMD:
                rf_write = (rtw_host_rfio) ? rtw_rf_hostwrite : rtw_rf_macwrite;
                break;
        }

        switch (rfchipid) {
        case RTW_RFCHIPID_GCT:
                rf = rtw_grf5101_create(&sc->sc_regs, rf_write, 0);
                sc->sc_pwrstate_cb = rtw_maxim_pwrstate;
                break;
        case RTW_RFCHIPID_MAXIM:
                rf = rtw_max2820_create(&sc->sc_regs, rf_write, 0);
                sc->sc_pwrstate_cb = rtw_maxim_pwrstate;
                break;
        case RTW_RFCHIPID_PHILIPS:
                rf = rtw_sa2400_create(&sc->sc_regs, rf_write, digphy);
                sc->sc_pwrstate_cb = rtw_philips_pwrstate;
                break;
        case RTW_RFCHIPID_RFMD:
                /* XXX RFMD has no RF constructor */
                sc->sc_pwrstate_cb = rtw_rfmd_pwrstate;
                /*FALLTHROUGH*/
        default:
                return NULL;
        }
        rf->rf_continuous_tx_cb =
            (rtw_continuous_tx_cb_t)rtw_continuous_tx_enable;
        rf->rf_continuous_tx_arg = (void *)sc;
        return rf;
}

/* Revision C and later use a different PHY delay setting than
 * revisions A and B.
 */
static uint8_t
rtw_check_phydelay(struct rtw_regs *regs, uint32_t old_rcr)
{
#define REVAB (RTW_RCR_MXDMA_UNLIMITED | RTW_RCR_AICV)
#define REVC (REVAB | RTW_RCR_RXFTH_WHOLE)

        uint8_t phydelay = __SHIFTIN(0x6, RTW_PHYDELAY_PHYDELAY);

        RTW_WRITE(regs, RTW_RCR, REVAB);
        RTW_WBW(regs, RTW_RCR, RTW_RCR);
        RTW_WRITE(regs, RTW_RCR, REVC);

        RTW_WBR(regs, RTW_RCR, RTW_RCR);
        if ((RTW_READ(regs, RTW_RCR) & REVC) == REVC)
                phydelay |= RTW_PHYDELAY_REVC_MAGIC;

        RTW_WRITE(regs, RTW_RCR, old_rcr);      /* restore RCR */
        RTW_SYNC(regs, RTW_RCR, RTW_RCR);

        return phydelay;
#undef REVC
}

void
rtw_attach(struct rtw_softc *sc)
{
        struct ifnet *ifp = &sc->sc_if;
        struct ieee80211com *ic = &sc->sc_ic;
        struct rtw_txsoft_blk *tsb;
        int pri, rc;

        pmf_self_suspensor_init(sc->sc_dev, &sc->sc_suspensor, &sc->sc_qual);

        rtw_cipher_wep = ieee80211_cipher_wep;
        rtw_cipher_wep.ic_decap = rtw_wep_decap;

        NEXT_ATTACH_STATE(sc, DETACHED);

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

        switch (RTW_READ(&sc->sc_regs, RTW_TCR) & RTW_TCR_HWVERID_MASK) {
        case RTW_TCR_HWVERID_F:
                sc->sc_hwverid = 'F';
                break;
        case RTW_TCR_HWVERID_D:
                sc->sc_hwverid = 'D';
                break;
        default:
                sc->sc_hwverid = '?';
                break;
        }
        aprint_verbose_dev(sc->sc_dev, "hardware version %c\n",
            sc->sc_hwverid);

        rc = bus_dmamem_alloc(sc->sc_dmat, sizeof(struct rtw_descs),
            RTW_DESC_ALIGNMENT, 0, &sc->sc_desc_segs, 1, &sc->sc_desc_nsegs,
            0);

        if (rc != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not allocate hw descriptors, error %d\n", rc);
                goto err;
        }

        NEXT_ATTACH_STATE(sc, FINISH_DESC_ALLOC);

        rc = bus_dmamem_map(sc->sc_dmat, &sc->sc_desc_segs,
            sc->sc_desc_nsegs, sizeof(struct rtw_descs),
            (void **)&sc->sc_descs, BUS_DMA_COHERENT);

        if (rc != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not map hw descriptors, error %d\n", rc);
                goto err;
        }
        NEXT_ATTACH_STATE(sc, FINISH_DESC_MAP);

        rc = bus_dmamap_create(sc->sc_dmat, sizeof(struct rtw_descs), 1,
            sizeof(struct rtw_descs), 0, 0, &sc->sc_desc_dmamap);

        if (rc != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not create DMA map for hw descriptors, error %d\n",
                    rc);
                goto err;
        }
        NEXT_ATTACH_STATE(sc, FINISH_DESCMAP_CREATE);

        sc->sc_rxdesc_blk.rdb_dmat = sc->sc_dmat;
        sc->sc_rxdesc_blk.rdb_dmamap = sc->sc_desc_dmamap;

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                sc->sc_txdesc_blk[pri].tdb_dmat = sc->sc_dmat;
                sc->sc_txdesc_blk[pri].tdb_dmamap = sc->sc_desc_dmamap;
        }

        rc = bus_dmamap_load(sc->sc_dmat, sc->sc_desc_dmamap, sc->sc_descs,
            sizeof(struct rtw_descs), NULL, 0);

        if (rc != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not load DMA map for hw descriptors, error %d\n",
                    rc);
                goto err;
        }
        NEXT_ATTACH_STATE(sc, FINISH_DESCMAP_LOAD);

        if (rtw_txsoft_blk_setup_all(sc) != 0)
                goto err;
        NEXT_ATTACH_STATE(sc, FINISH_TXCTLBLK_SETUP);

        rtw_txdesc_blk_setup_all(sc);

        NEXT_ATTACH_STATE(sc, FINISH_TXDESCBLK_SETUP);

        sc->sc_rxdesc_blk.rdb_desc = &sc->sc_descs->hd_rx[0];

        for (pri = 0; pri < RTW_NTXPRI; pri++) {
                tsb = &sc->sc_txsoft_blk[pri];

                if ((rc = rtw_txdesc_dmamaps_create(sc->sc_dmat,
                    &tsb->tsb_desc[0], tsb->tsb_ndesc)) != 0) {
                        aprint_error_dev(sc->sc_dev,
                            "could not load DMA map for hw tx descriptors, "
                            "error %d\n", rc);
                        goto err;
                }
        }

        NEXT_ATTACH_STATE(sc, FINISH_TXMAPS_CREATE);
        if ((rc = rtw_rxdesc_dmamaps_create(sc->sc_dmat, &sc->sc_rxsoft[0],
                                            RTW_RXQLEN)) != 0) {
                aprint_error_dev(sc->sc_dev,
                    "could not load DMA map for hw rx descriptors, error %d\n",
                    rc);
                goto err;
        }
        NEXT_ATTACH_STATE(sc, FINISH_RXMAPS_CREATE);

        /* Reset the chip to a known state. */
        if (rtw_reset(sc) != 0)
                goto err;
        NEXT_ATTACH_STATE(sc, FINISH_RESET);

        sc->sc_rcr = RTW_READ(&sc->sc_regs, RTW_RCR);

        if ((sc->sc_rcr & RTW_RCR_9356SEL) != 0)
                sc->sc_flags |= RTW_F_9356SROM;

        if (rtw_srom_read(&sc->sc_regs, sc->sc_flags, &sc->sc_srom,
            sc->sc_dev) != 0)
                goto err;

        NEXT_ATTACH_STATE(sc, FINISH_READ_SROM);

        if (rtw_srom_parse(&sc->sc_srom, &sc->sc_flags, &sc->sc_csthr,
            &sc->sc_rfchipid, &sc->sc_rcr, &sc->sc_locale,
            sc->sc_dev) != 0) {
                aprint_error_dev(sc->sc_dev,
                    "attach failed, malformed serial ROM\n");
                goto err;
        }

        aprint_verbose_dev(sc->sc_dev, "%s PHY\n",
            ((sc->sc_flags & RTW_F_DIGPHY) != 0) ? "digital" : "analog");

        aprint_verbose_dev(sc->sc_dev, "carrier-sense threshold %u\n",
            sc->sc_csthr);

        NEXT_ATTACH_STATE(sc, FINISH_PARSE_SROM);

        sc->sc_rf = rtw_rf_attach(sc, sc->sc_rfchipid,
            sc->sc_flags & RTW_F_DIGPHY);

        if (sc->sc_rf == NULL) {
                aprint_verbose_dev(sc->sc_dev,
                    "attach failed, could not attach RF\n");
                goto err;
        }

        NEXT_ATTACH_STATE(sc, FINISH_RF_ATTACH);

        sc->sc_phydelay = rtw_check_phydelay(&sc->sc_regs, sc->sc_rcr);

        RTW_DPRINTF(RTW_DEBUG_ATTACH,
            ("%s: PHY delay %d\n", device_xname(sc->sc_dev), sc->sc_phydelay));

        if (sc->sc_locale == RTW_LOCALE_UNKNOWN)
                rtw_identify_country(&sc->sc_regs, &sc->sc_locale);

        rtw_init_channels(sc->sc_locale, &sc->sc_ic.ic_channels, sc->sc_dev);

        if (rtw_identify_sta(&sc->sc_regs, &sc->sc_ic.ic_myaddr,
            sc->sc_dev) != 0)
                goto err;
        NEXT_ATTACH_STATE(sc, FINISH_ID_STA);

        rtw_setifprops(ifp, device_xname(sc->sc_dev), (void*)sc);

        IFQ_SET_READY(&ifp->if_snd);

        sc->sc_ic.ic_ifp = ifp;
        rtw_set80211props(&sc->sc_ic);

        rtw_led_attach(&sc->sc_led_state, (void *)sc);
        NEXT_ATTACH_STATE(sc, FINISH_LED_ATTACH);

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

        rtw_set80211methods(&sc->sc_mtbl, &sc->sc_ic);

        /* possibly we should fill in our own sc_send_prresp, since
         * the RTL8180 is probably sending probe responses in ad hoc
         * mode.
         */

        /* complete initialization */
        ieee80211_media_init(&sc->sc_ic, rtw_media_change, rtw_media_status);
        callout_init(&sc->sc_scan_ch, 0);

        rtw_init_radiotap(sc);

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

        NEXT_ATTACH_STATE(sc, FINISHED);

        ieee80211_announce(ic);
        return;
err:
        rtw_detach(sc);
        return;
}

int
rtw_detach(struct rtw_softc *sc)
{
        struct ifnet *ifp = &sc->sc_if;
        int pri, s;

        s = splnet();

        switch (sc->sc_attach_state) {
        case FINISHED:
                rtw_stop(ifp, 1);

                pmf_device_deregister(sc->sc_dev);
                callout_stop(&sc->sc_scan_ch);
                ieee80211_ifdetach(&sc->sc_ic);
                if_detach(ifp);
                /*FALLTHROUGH*/
        case FINISH_LED_ATTACH:
                rtw_led_detach(&sc->sc_led_state);
                /*FALLTHROUGH*/
        case FINISH_ID_STA:
        case FINISH_RF_ATTACH:
                rtw_rf_destroy(sc->sc_rf);
                sc->sc_rf = NULL;
                /*FALLTHROUGH*/
        case FINISH_PARSE_SROM:
        case FINISH_READ_SROM:
                rtw_srom_free(&sc->sc_srom);
                /*FALLTHROUGH*/
        case FINISH_RESET:
        case FINISH_RXMAPS_CREATE:
                rtw_rxdesc_dmamaps_destroy(sc->sc_dmat, &sc->sc_rxsoft[0],
                    RTW_RXQLEN);
                /*FALLTHROUGH*/
        case FINISH_TXMAPS_CREATE:
                for (pri = 0; pri < RTW_NTXPRI; pri++) {
                        rtw_txdesc_dmamaps_destroy(sc->sc_dmat,
                            sc->sc_txsoft_blk[pri].tsb_desc,
                            sc->sc_txsoft_blk[pri].tsb_ndesc);
                }
                /*FALLTHROUGH*/
        case FINISH_TXDESCBLK_SETUP:
        case FINISH_TXCTLBLK_SETUP:
                rtw_txsoft_blk_cleanup_all(sc);
                /*FALLTHROUGH*/
        case FINISH_DESCMAP_LOAD:
                bus_dmamap_unload(sc->sc_dmat, sc->sc_desc_dmamap);
                /*FALLTHROUGH*/
        case FINISH_DESCMAP_CREATE:
                bus_dmamap_destroy(sc->sc_dmat, sc->sc_desc_dmamap);
                /*FALLTHROUGH*/
        case FINISH_DESC_MAP:
                bus_dmamem_unmap(sc->sc_dmat, (void *)sc->sc_descs,
                    sizeof(struct rtw_descs));
                /*FALLTHROUGH*/
        case FINISH_DESC_ALLOC:
                bus_dmamem_free(sc->sc_dmat, &sc->sc_desc_segs,
                    sc->sc_desc_nsegs);
                /*FALLTHROUGH*/
        case DETACHED:
                if (sc->sc_soft_ih != NULL) {
                        softint_disestablish(sc->sc_soft_ih);
                        sc->sc_soft_ih = NULL;
                }
                NEXT_ATTACH_STATE(sc, DETACHED);
                break;
        }
        splx(s);
        return 0;
}