root/sys/dev/rtwn/if_rtwn_beacon.c
/*-
 * Copyright (c) 2010 Damien Bergamini <damien.bergamini@free.fr>
 * Copyright (c) 2014 Kevin Lo <kevlo@FreeBSD.org>
 * Copyright (c) 2015-2016 Andriy Voskoboinyk <avos@FreeBSD.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/queue.h>
#include <sys/taskqueue.h>
#include <sys/bus.h>
#include <sys/endian.h>

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

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

#include <dev/rtwn/if_rtwnvar.h>

#include <dev/rtwn/if_rtwn_beacon.h>
#include <dev/rtwn/if_rtwn_debug.h>
#include <dev/rtwn/if_rtwn_tx.h>

#include <dev/rtwn/rtl8192c/r92c_reg.h>

static void
rtwn_reset_beacon_valid(struct rtwn_softc *sc, int id)
{

        KASSERT (id == 0 || id == 1, ("wrong port id %d\n", id));

        /* XXX cannot be cleared on RTL8188CE */
        rtwn_setbits_1_shift(sc, sc->bcn_status_reg[id],
            R92C_TDECTRL_BCN_VALID, 0, 2);

        RTWN_DPRINTF(sc, RTWN_DEBUG_BEACON,
            "%s: 'beacon valid' bit for vap %d was unset\n",
            __func__, id);
}

static int
rtwn_check_beacon_valid(struct rtwn_softc *sc, int id)
{
        uint16_t reg;
        int ntries;

        if (id == RTWN_VAP_ID_INVALID)
                return (0);

        reg = sc->bcn_status_reg[id];
        for (ntries = 0; ntries < 10; ntries++) {
                if (rtwn_read_4(sc, reg) & R92C_TDECTRL_BCN_VALID) {
                        RTWN_DPRINTF(sc, RTWN_DEBUG_BEACON,
                            "%s: beacon for vap %d was recognized\n",
                            __func__, id);
                        break;
                }
                rtwn_delay(sc, sc->bcn_check_interval);
        }
        if (ntries == 10)
                return (ETIMEDOUT);

        return (0);
}

void
rtwn_switch_bcnq(struct rtwn_softc *sc, int id)
{

        if (sc->cur_bcnq_id != id) {
                /* Wait until any previous transmit completes. */
                (void) rtwn_check_beacon_valid(sc, sc->cur_bcnq_id);

                /* Change current port. */
                rtwn_beacon_select(sc, id);
                sc->cur_bcnq_id = id;
        }

        /* Reset 'beacon valid' bit. */
        rtwn_reset_beacon_valid(sc, id);
}

int
rtwn_setup_beacon(struct rtwn_softc *sc, struct ieee80211_node *ni)
{
        struct ieee80211vap *vap = ni->ni_vap;
        struct rtwn_vap *uvp = RTWN_VAP(vap);
        struct mbuf *m;

        RTWN_ASSERT_LOCKED(sc);

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

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

        if (uvp->bcn_mbuf != NULL) {
                rtwn_beacon_unload(sc, uvp->id);
                m_freem(uvp->bcn_mbuf);
        }

        uvp->bcn_mbuf = m;

        rtwn_beacon_set_rate(sc, &uvp->bcn_desc.txd[0],
            IEEE80211_IS_CHAN_5GHZ(ni->ni_chan));

        return (rtwn_tx_beacon_check(sc, uvp));
}

/*
 * Push a beacon frame into the chip. Beacon will
 * be repeated by the chip every R92C_BCN_INTERVAL.
 */
static int
rtwn_tx_beacon(struct rtwn_softc *sc, struct rtwn_vap *uvp)
{
        int error;

        RTWN_ASSERT_LOCKED(sc);

        RTWN_DPRINTF(sc, RTWN_DEBUG_BEACON,
            "%s: sending beacon for vap %d\n", __func__, uvp->id);

        error = rtwn_tx_start(sc, NULL, uvp->bcn_mbuf, &uvp->bcn_desc.txd[0],
            IEEE80211_FC0_TYPE_MGT, uvp->id);

        return (error);
}

void
rtwn_update_beacon(struct ieee80211vap *vap, int item)
{
        struct ieee80211com *ic = vap->iv_ic;
        struct rtwn_softc *sc = ic->ic_softc;
        struct rtwn_vap *uvp = RTWN_VAP(vap);
        struct ieee80211_beacon_offsets *bo = &vap->iv_bcn_off;
        struct ieee80211_node *ni = vap->iv_bss;
        int mcast = 0;

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

        RTWN_DPRINTF(sc, RTWN_DEBUG_BEACON,
            "%s: vap id %d, iv_csa_count %d, ic_csa_count %d, item %d\n",
            __func__, uvp->id, vap->iv_csa_count, ic->ic_csa_count, item);

        switch (item) {
        case IEEE80211_BEACON_CSA:
                if (vap->iv_csa_count != ic->ic_csa_count) {
                        /*
                         * XXX two APs with different beacon intervals
                         * are not handled properly.
                         */
                        /* XXX check TBTT? */
                        taskqueue_enqueue_timeout(taskqueue_thread,
                            &uvp->tx_beacon_csa,
                            msecs_to_ticks(ni->ni_intval));
                }
                break;
        case IEEE80211_BEACON_TIM:
                mcast = 1;      /* XXX */
                break;
        default:
                break;
        }

        setbit(bo->bo_flags, item);

        rtwn_beacon_update_begin(sc, vap);
        RTWN_UNLOCK(sc);

        ieee80211_beacon_update(ni, uvp->bcn_mbuf, mcast);

        /* XXX clear manually */
        clrbit(bo->bo_flags, IEEE80211_BEACON_CSA);

        RTWN_LOCK(sc);
        rtwn_tx_beacon(sc, uvp);
        rtwn_beacon_update_end(sc, vap);
        RTWN_UNLOCK(sc);
}

void
rtwn_tx_beacon_csa(void *arg, int npending __unused)
{
        struct ieee80211vap *vap = arg;
        struct ieee80211com *ic = vap->iv_ic;
        struct rtwn_softc *sc = ic->ic_softc;
        struct rtwn_vap *rvp = RTWN_VAP(vap);

        KASSERT (rvp->id == 0 || rvp->id == 1,
            ("wrong port id %d\n", rvp->id));

        IEEE80211_LOCK(ic);
        if (ic->ic_flags & IEEE80211_F_CSAPENDING) {
                RTWN_DPRINTF(sc, RTWN_DEBUG_BEACON,
                    "%s: vap id %d, iv_csa_count %d, ic_csa_count %d\n",
                    __func__, rvp->id, vap->iv_csa_count, ic->ic_csa_count);

                rtwn_update_beacon(vap, IEEE80211_BEACON_CSA);
        }
        IEEE80211_UNLOCK(ic);

        (void) rvp;
}

int
rtwn_tx_beacon_check(struct rtwn_softc *sc, struct rtwn_vap *uvp)
{
        int ntries, error;

        for (ntries = 0; ntries < 5; ntries++) {
                rtwn_reset_beacon_valid(sc, uvp->id);

                error = rtwn_tx_beacon(sc, uvp);
                if (error != 0)
                        continue;

                error = rtwn_check_beacon_valid(sc, uvp->id);
                if (error == 0)
                        break;
        }
        if (ntries == 5) {
                device_printf(sc->sc_dev,
                    "%s: cannot push beacon into chip, error %d!\n",
                    __func__, error);
                return (error);
        }

        return (0);
}