ath9k: switch channel context for beaconing

Add a basic state machine for switch channel context
for beacon transmission.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index a0c7279e43642a80818b41757bc2652145a01a80..b657115d1eb76c26541351a8234ca11984b533fe 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -341,6 +341,28 @@ struct ath_chanctx {
        bool stopped;
        bool active;
        bool assigned;
+       bool switch_after_beacon;
+};
+
+enum ath_chanctx_event {
+       ATH_CHANCTX_EVENT_BEACON_PREPARE,
+       ATH_CHANCTX_EVENT_BEACON_SENT,
+       ATH_CHANCTX_EVENT_TSF_TIMER,
+};
+
+enum ath_chanctx_state {
+       ATH_CHANCTX_STATE_IDLE,
+       ATH_CHANCTX_STATE_WAIT_FOR_BEACON,
+       ATH_CHANCTX_STATE_WAIT_FOR_TIMER,
+       ATH_CHANCTX_STATE_SWITCH,
+};
+
+struct ath_chanctx_sched {
+       bool beacon_pending;
+       enum ath_chanctx_state state;
+
+       u32 next_tbtt;
+       unsigned int channel_switch_time;
 };
 
 enum ath_offchannel_state {
@@ -388,6 +410,8 @@ void ath_chanctx_offchan_switch(struct ath_softc *sc,
                                struct ieee80211_channel *chan);
 struct ath_chanctx *ath_chanctx_get_oper_chan(struct ath_softc *sc,
                                              bool active);
+void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif,
+                      enum ath_chanctx_event ev);
 
 int ath_reset_internal(struct ath_softc *sc, struct ath9k_channel *hchan);
 int ath_startrecv(struct ath_softc *sc);
@@ -826,6 +850,7 @@ struct ath_softc {
        struct ath_chanctx *next_chan;
        spinlock_t chan_lock;
        struct ath_offchannel offchannel;
+       struct ath_chanctx_sched sched;
 
 #ifdef CONFIG_MAC80211_LEDS
        bool led_registered;

diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index d3553927c6dddc387fcdaa1587305075a7b0d934..5b1689cf029ad86c033ca08ad1ba89a3d8065d04 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -374,12 +374,19 @@ void ath9k_beacon_tasklet(unsigned long data)
        vif = sc->beacon.bslot[slot];
 
        /* EDMA devices check that in the tx completion function. */
-       if (!edma && ath9k_csa_is_finished(sc, vif))
-               return;
+       if (!edma) {
+               if (sc->sched.beacon_pending)
+                       ath_chanctx_event(sc, NULL,
+                                         ATH_CHANCTX_EVENT_BEACON_SENT);
+
+               if (ath9k_csa_is_finished(sc, vif))
+                       return;
+       }
 
        if (!vif || !vif->bss_conf.enable_beacon)
                return;
 
+       ath_chanctx_event(sc, vif, ATH_CHANCTX_EVENT_BEACON_PREPARE);
        bf = ath9k_beacon_generate(sc->hw, vif);
 
        if (sc->beacon.bmisscnt != 0) {

diff --git a/drivers/net/wireless/ath/ath9k/channel.c b/drivers/net/wireless/ath/ath9k/channel.c
index 156625318d04f456836a2b52d58761553224feb8..503b7766e12e7a4a9ac1a11e0e51ba51293159de 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/channel.c
+++ b/drivers/net/wireless/ath/ath9k/channel.c
@@ -202,10 +202,33 @@ ath_chanctx_send_ps_frame(struct ath_softc *sc, bool powersave)
        return sent;
 }
 
+static bool ath_chanctx_defer_switch(struct ath_softc *sc)
+{
+       if (sc->cur_chan == &sc->offchannel.chan)
+               return false;
+
+       switch (sc->sched.state) {
+       case ATH_CHANCTX_STATE_SWITCH:
+               return false;
+       case ATH_CHANCTX_STATE_IDLE:
+               if (!sc->cur_chan->switch_after_beacon)
+                       return false;
+
+               sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_BEACON;
+               break;
+       default:
+               break;
+       }
+
+       return true;
+}
+
 void ath_chanctx_work(struct work_struct *work)
 {
        struct ath_softc *sc = container_of(work, struct ath_softc,
                                            chanctx_work);
+       struct timespec ts;
+       bool measure_time = false;
        bool send_ps = false;
 
        mutex_lock(&sc->mutex);
@@ -216,10 +239,20 @@ void ath_chanctx_work(struct work_struct *work)
                return;
        }
 
+       if (ath_chanctx_defer_switch(sc)) {
+               spin_unlock_bh(&sc->chan_lock);
+               mutex_unlock(&sc->mutex);
+               return;
+       }
+
        if (sc->cur_chan != sc->next_chan) {
                sc->cur_chan->stopped = true;
                spin_unlock_bh(&sc->chan_lock);
 
+               if (sc->next_chan == &sc->offchannel.chan) {
+                       getrawmonotonic(&ts);
+                       measure_time = true;
+               }
                __ath9k_flush(sc->hw, ~0, true);
 
                if (ath_chanctx_send_ps_frame(sc, true))
@@ -236,13 +269,17 @@ void ath_chanctx_work(struct work_struct *work)
        sc->cur_chan = sc->next_chan;
        sc->cur_chan->stopped = false;
        sc->next_chan = NULL;
+       sc->sched.state = ATH_CHANCTX_STATE_IDLE;
        spin_unlock_bh(&sc->chan_lock);
 
        if (sc->sc_ah->chip_fullsleep ||
            memcmp(&sc->cur_chandef, &sc->cur_chan->chandef,
-                  sizeof(sc->cur_chandef)))
+                  sizeof(sc->cur_chandef))) {
                ath_set_channel(sc);
-
+               if (measure_time)
+                       sc->sched.channel_switch_time =
+                               ath9k_hw_get_tsf_offset(&ts, NULL);
+       }
        if (send_ps)
                ath_chanctx_send_ps_frame(sc, false);
 
@@ -335,3 +372,46 @@ void ath_chanctx_offchan_switch(struct ath_softc *sc,
 
        ath_chanctx_switch(sc, &sc->offchannel.chan, &chandef);
 }
+
+void ath_chanctx_event(struct ath_softc *sc, struct ieee80211_vif *vif,
+                      enum ath_chanctx_event ev)
+{
+       struct ath_hw *ah = sc->sc_ah;
+       u32 tsf_time;
+
+       spin_lock_bh(&sc->chan_lock);
+
+       switch (ev) {
+       case ATH_CHANCTX_EVENT_BEACON_PREPARE:
+               if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
+                       break;
+
+               sc->sched.beacon_pending = true;
+               sc->sched.next_tbtt = REG_READ(ah, AR_NEXT_TBTT_TIMER);
+               break;
+       case ATH_CHANCTX_EVENT_BEACON_SENT:
+               if (!sc->sched.beacon_pending)
+                       break;
+
+               sc->sched.beacon_pending = false;
+               if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_BEACON)
+                       break;
+
+               /* defer channel switch by a quarter beacon interval */
+               tsf_time = TU_TO_USEC(sc->cur_chan->beacon.beacon_interval);
+               tsf_time = sc->sched.next_tbtt + tsf_time / 4;
+               sc->sched.state = ATH_CHANCTX_STATE_WAIT_FOR_TIMER;
+               ath9k_hw_gen_timer_start(ah, sc->p2p_ps_timer, tsf_time,
+                               1000000);
+               break;
+       case ATH_CHANCTX_EVENT_TSF_TIMER:
+               if (sc->sched.state != ATH_CHANCTX_STATE_WAIT_FOR_TIMER)
+                       break;
+
+               sc->sched.state = ATH_CHANCTX_STATE_SWITCH;
+               ieee80211_queue_work(sc->hw, &sc->chanctx_work);
+               break;
+       }
+
+       spin_unlock_bh(&sc->chan_lock);
+}

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 9dfb82077016c05c019f2bc8696e2e9899c65188..2393af058afe143ce1ef513b714b2278262bd5e6 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1047,10 +1047,14 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 
        ath9k_hw_setopmode(ah);
 
+       ctx->switch_after_beacon = false;
        if ((iter_data.nstations + iter_data.nadhocs + iter_data.nmeshes) > 0)
                ah->imask |= ATH9K_INT_TSFOOR;
-       else
+       else {
                ah->imask &= ~ATH9K_INT_TSFOOR;
+               if (iter_data.naps == 1 && iter_data.beacons)
+                       ctx->switch_after_beacon = true;
+       }
 
        ah->imask &= ~ATH9K_INT_SWBA;
        if (ah->opmode == NL80211_IFTYPE_STATION) {
@@ -1664,6 +1668,9 @@ void ath9k_p2p_ps_timer(void *priv)
        struct ath_node *an;
        u32 tsf;
 
+       ath9k_hw_gen_timer_stop(sc->sc_ah, sc->p2p_ps_timer);
+       ath_chanctx_event(sc, NULL, ATH_CHANCTX_EVENT_TSF_TIMER);
+
        if (!avp || avp->chanctx != sc->cur_chan)
                return;
 

diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 7dd6187761c1325de8cc38539115b5f56812b9d1..a422c20fe065716aaf6072116c703c3facfc3fc3 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -2617,6 +2617,8 @@ void ath_tx_edma_tasklet(struct ath_softc *sc)
                        sc->beacon.tx_processed = true;
                        sc->beacon.tx_last = !(ts.ts_status & ATH9K_TXERR_MASK);
 
+                       ath_chanctx_event(sc, NULL,
+                                         ATH_CHANCTX_EVENT_BEACON_SENT);
                        ath9k_csa_update(sc);
                        continue;
                }