[PATCH 1/6] ath9k: Correct TSF adjustment to align the beacon time correctly

[PATCH 1/6] ath9k: Correct TSF adjustment to align the beacon time correctly

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Beacons need to be send out at timestamp % beacon_time == 0.

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/beacon.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 5cf0cd7..800c96b 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -279,17 +279,21 @@ static void ath9k_set_tsfadjust(struct ath_softc *sc, struct ieee80211_vif *vif)
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 	struct ath_vif *avp = (void *)vif->drv_priv;
 	struct ath_beacon_config *cur_conf = &avp->chanctx->beacon;
-	u32 tsfadjust;
+	s64 tsfadjust;
 
 	if (avp->av_bslot == 0)
 		return;
 
+	/* tsf_adjust is added to the TSF value. We send out the beacon late,
+	 * so need to adjust the TSF starting point to be later in time (i.e.
+	 * the theoretical first beacon has a TSF of 0 after correction).
+	 */
 	tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
-	tsfadjust = TU_TO_USEC(tsfadjust) / ATH_BCBUF;
+	tsfadjust = -TU_TO_USEC(tsfadjust) / ATH_BCBUF;
 	avp->tsf_adjust = cpu_to_le64(tsfadjust);
 
-	ath_dbg(common, CONFIG, "tsfadjust is: %llu for bslot: %d\n",
-		(unsigned long long)tsfadjust, avp->av_bslot);
+	ath_dbg(common, CONFIG, "tsfadjust is: %lld for bslot: %d\n",
+		(signed long long)tsfadjust, avp->av_bslot);
 }
 
 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif)
-- 
2.8.1

[ath9k-devel] [PATCH 1/6] ath9k: Correct TSF adjustment to align the beacon time correctly

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Beacons need to be send out at timestamp % beacon_time == 0.

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/beacon.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 5cf0cd7..800c96b 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -279,17 +279,21 @@ static void ath9k_set_tsfadjust(struct ath_softc *sc, struct ieee80211_vif *vif)
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 	struct ath_vif *avp = (void *)vif->drv_priv;
 	struct ath_beacon_config *cur_conf = &avp->chanctx->beacon;
-	u32 tsfadjust;
+	s64 tsfadjust;
 
 	if (avp->av_bslot == 0)
 		return;
 
+	/* tsf_adjust is added to the TSF value. We send out the beacon late,
+	 * so need to adjust the TSF starting point to be later in time (i.e.
+	 * the theoretical first beacon has a TSF of 0 after correction).
+	 */
 	tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
-	tsfadjust = TU_TO_USEC(tsfadjust) / ATH_BCBUF;
+	tsfadjust = -TU_TO_USEC(tsfadjust) / ATH_BCBUF;
 	avp->tsf_adjust = cpu_to_le64(tsfadjust);
 
-	ath_dbg(common, CONFIG, "tsfadjust is: %llu for bslot: %d\n",
-		(unsigned long long)tsfadjust, avp->av_bslot);
+	ath_dbg(common, CONFIG, "tsfadjust is: %lld for bslot: %d\n",
+		(signed long long)tsfadjust, avp->av_bslot);
 }
 
 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif)
-- 
2.8.1

[PATCH 2/6] ath9k: Handle channel context in get_/set_/reset_tsf

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/main.c | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 8b63988..375c2ac 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1823,11 +1823,18 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 static u64 ath9k_get_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 {
 	struct ath_softc *sc = hw->priv;
+	struct ath_vif *avp = (void *)vif->drv_priv;
 	u64 tsf;
 
 	mutex_lock(&sc->mutex);
 	ath9k_ps_wakeup(sc);
-	tsf = ath9k_hw_gettsf64(sc->sc_ah);
+	/* Get current TSF either from HW or kernel time. */
+	if (sc->cur_chan == avp->chanctx) {
+		tsf = ath9k_hw_gettsf64(sc->sc_ah);
+	} else {
+		tsf = sc->cur_chan->tsf_val +
+		      ath9k_hw_get_tsf_offset(&sc->cur_chan->tsf_ts, NULL);
+	}
 	ath9k_ps_restore(sc);
 	mutex_unlock(&sc->mutex);
 
@@ -1839,10 +1846,14 @@ static void ath9k_set_tsf(struct ieee80211_hw *hw,
 			  u64 tsf)
 {
 	struct ath_softc *sc = hw->priv;
+	struct ath_vif *avp = (void *)vif->drv_priv;
 
 	mutex_lock(&sc->mutex);
 	ath9k_ps_wakeup(sc);
-	ath9k_hw_settsf64(sc->sc_ah, tsf);
+	getrawmonotonic(&avp->chanctx->tsf_ts);
+	if (sc->cur_chan == avp->chanctx)
+		ath9k_hw_settsf64(sc->sc_ah, tsf);
+	avp->chanctx->tsf_val = tsf;
 	ath9k_ps_restore(sc);
 	mutex_unlock(&sc->mutex);
 }
@@ -1850,11 +1861,15 @@ static void ath9k_set_tsf(struct ieee80211_hw *hw,
 static void ath9k_reset_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 {
 	struct ath_softc *sc = hw->priv;
+	struct ath_vif *avp = (void *)vif->drv_priv;
 
 	mutex_lock(&sc->mutex);
 
 	ath9k_ps_wakeup(sc);
-	ath9k_hw_reset_tsf(sc->sc_ah);
+	getrawmonotonic(&avp->chanctx->tsf_ts);
+	if (sc->cur_chan == avp->chanctx)
+		ath9k_hw_reset_tsf(sc->sc_ah);
+	avp->chanctx->tsf_val = 0;
 	ath9k_ps_restore(sc);
 
 	mutex_unlock(&sc->mutex);
-- 
2.8.1

[ath9k-devel] [PATCH 2/6] ath9k: Handle channel context in get_/set_/reset_tsf

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/main.c | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 8b63988..375c2ac 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1823,11 +1823,18 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 static u64 ath9k_get_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 {
 	struct ath_softc *sc = hw->priv;
+	struct ath_vif *avp = (void *)vif->drv_priv;
 	u64 tsf;
 
 	mutex_lock(&sc->mutex);
 	ath9k_ps_wakeup(sc);
-	tsf = ath9k_hw_gettsf64(sc->sc_ah);
+	/* Get current TSF either from HW or kernel time. */
+	if (sc->cur_chan == avp->chanctx) {
+		tsf = ath9k_hw_gettsf64(sc->sc_ah);
+	} else {
+		tsf = sc->cur_chan->tsf_val +
+		      ath9k_hw_get_tsf_offset(&sc->cur_chan->tsf_ts, NULL);
+	}
 	ath9k_ps_restore(sc);
 	mutex_unlock(&sc->mutex);
 
@@ -1839,10 +1846,14 @@ static void ath9k_set_tsf(struct ieee80211_hw *hw,
 			  u64 tsf)
 {
 	struct ath_softc *sc = hw->priv;
+	struct ath_vif *avp = (void *)vif->drv_priv;
 
 	mutex_lock(&sc->mutex);
 	ath9k_ps_wakeup(sc);
-	ath9k_hw_settsf64(sc->sc_ah, tsf);
+	getrawmonotonic(&avp->chanctx->tsf_ts);
+	if (sc->cur_chan == avp->chanctx)
+		ath9k_hw_settsf64(sc->sc_ah, tsf);
+	avp->chanctx->tsf_val = tsf;
 	ath9k_ps_restore(sc);
 	mutex_unlock(&sc->mutex);
 }
@@ -1850,11 +1861,15 @@ static void ath9k_set_tsf(struct ieee80211_hw *hw,
 static void ath9k_reset_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 {
 	struct ath_softc *sc = hw->priv;
+	struct ath_vif *avp = (void *)vif->drv_priv;
 
 	mutex_lock(&sc->mutex);
 
 	ath9k_ps_wakeup(sc);
-	ath9k_hw_reset_tsf(sc->sc_ah);
+	getrawmonotonic(&avp->chanctx->tsf_ts);
+	if (sc->cur_chan == avp->chanctx)
+		ath9k_hw_reset_tsf(sc->sc_ah);
+	avp->chanctx->tsf_val = 0;
 	ath9k_ps_restore(sc);
 
 	mutex_unlock(&sc->mutex);
-- 
2.8.1

Re: [PATCH 2/6] ath9k: Handle channel context in get_/set_/reset_tsf

[Kalle Valo]

Benjamin Berg <benjamin@sipsolutions.net> writes:

> From: Benjamin Berg <benjamin.berg@open-mesh.com>
>
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>

Please avoid empty commit logs, it's just unfriendly to everyone. It
doesn't take long for you to answer "Why?" in the log.

-- 
Kalle Valo

[ath9k-devel] [PATCH 2/6] ath9k: Handle channel context in get_/set_/reset_tsf

[Kalle Valo]

Benjamin Berg <benjamin@sipsolutions.net> writes:

> From: Benjamin Berg <benjamin.berg@open-mesh.com>
>
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>

Please avoid empty commit logs, it's just unfriendly to everyone. It
doesn't take long for you to answer "Why?" in the log.

-- 
Kalle Valo

[PATCH 3/6] ath9k: Use tsf offset helper in ath9k_hw_reset

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Not much of a change. Only small fix is that we don't assume that
exactly 1.5ms have passed for the second AR91xx SoC TSF setting.

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/hw.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index 8b2895f..1c27e2d 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1832,8 +1832,9 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	u32 saveLedState;
 	u32 saveDefAntenna;
 	u32 macStaId1;
+	struct timespec tsf_ts;
+	u32 tsf_offset;
 	u64 tsf = 0;
-	s64 usec = 0;
 	int r;
 	bool start_mci_reset = false;
 	bool save_fullsleep = ah->chip_fullsleep;
@@ -1877,8 +1878,8 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	macStaId1 = REG_READ(ah, AR_STA_ID1) & AR_STA_ID1_BASE_RATE_11B;
 
 	/* Save TSF before chip reset, a cold reset clears it */
+	getrawmonotonic(&tsf_ts);
 	tsf = ath9k_hw_gettsf64(ah);
-	usec = ktime_to_us(ktime_get_raw());
 
 	saveLedState = REG_READ(ah, AR_CFG_LED) &
 		(AR_CFG_LED_ASSOC_CTL | AR_CFG_LED_MODE_SEL |
@@ -1911,8 +1912,8 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	}
 
 	/* Restore TSF */
-	usec = ktime_to_us(ktime_get_raw()) - usec;
-	ath9k_hw_settsf64(ah, tsf + usec);
+	tsf_offset = ath9k_hw_get_tsf_offset(&tsf_ts, NULL);
+	ath9k_hw_settsf64(ah, tsf + tsf_offset);
 
 	if (AR_SREV_9280_20_OR_LATER(ah))
 		REG_SET_BIT(ah, AR_GPIO_INPUT_EN_VAL, AR_GPIO_JTAG_DISABLE);
@@ -1932,12 +1933,11 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	/*
 	 * Some AR91xx SoC devices frequently fail to accept TSF writes
 	 * right after the chip reset. When that happens, write a new
-	 * value after the initvals have been applied, with an offset
-	 * based on measured time difference
+	 * value after the initvals have been applied.
 	 */
 	if (AR_SREV_9100(ah) && (ath9k_hw_gettsf64(ah) < tsf)) {
-		tsf += 1500;
-		ath9k_hw_settsf64(ah, tsf);
+		tsf_offset = ath9k_hw_get_tsf_offset(&tsf_ts, NULL);
+		ath9k_hw_settsf64(ah, tsf + tsf_offset);
 	}
 
 	ath9k_hw_init_mfp(ah);
-- 
2.8.1

[ath9k-devel] [PATCH 3/6] ath9k: Use tsf offset helper in ath9k_hw_reset

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Not much of a change. Only small fix is that we don't assume that
exactly 1.5ms have passed for the second AR91xx SoC TSF setting.

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/hw.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index 8b2895f..1c27e2d 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1832,8 +1832,9 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	u32 saveLedState;
 	u32 saveDefAntenna;
 	u32 macStaId1;
+	struct timespec tsf_ts;
+	u32 tsf_offset;
 	u64 tsf = 0;
-	s64 usec = 0;
 	int r;
 	bool start_mci_reset = false;
 	bool save_fullsleep = ah->chip_fullsleep;
@@ -1877,8 +1878,8 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	macStaId1 = REG_READ(ah, AR_STA_ID1) & AR_STA_ID1_BASE_RATE_11B;
 
 	/* Save TSF before chip reset, a cold reset clears it */
+	getrawmonotonic(&tsf_ts);
 	tsf = ath9k_hw_gettsf64(ah);
-	usec = ktime_to_us(ktime_get_raw());
 
 	saveLedState = REG_READ(ah, AR_CFG_LED) &
 		(AR_CFG_LED_ASSOC_CTL | AR_CFG_LED_MODE_SEL |
@@ -1911,8 +1912,8 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	}
 
 	/* Restore TSF */
-	usec = ktime_to_us(ktime_get_raw()) - usec;
-	ath9k_hw_settsf64(ah, tsf + usec);
+	tsf_offset = ath9k_hw_get_tsf_offset(&tsf_ts, NULL);
+	ath9k_hw_settsf64(ah, tsf + tsf_offset);
 
 	if (AR_SREV_9280_20_OR_LATER(ah))
 		REG_SET_BIT(ah, AR_GPIO_INPUT_EN_VAL, AR_GPIO_JTAG_DISABLE);
@@ -1932,12 +1933,11 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
 	/*
 	 * Some AR91xx SoC devices frequently fail to accept TSF writes
 	 * right after the chip reset. When that happens, write a new
-	 * value after the initvals have been applied, with an offset
-	 * based on measured time difference
+	 * value after the initvals have been applied.
 	 */
 	if (AR_SREV_9100(ah) && (ath9k_hw_gettsf64(ah) < tsf)) {
-		tsf += 1500;
-		ath9k_hw_settsf64(ah, tsf);
+		tsf_offset = ath9k_hw_get_tsf_offset(&tsf_ts, NULL);
+		ath9k_hw_settsf64(ah, tsf + tsf_offset);
 	}
 
 	ath9k_hw_init_mfp(ah);
-- 
2.8.1

Re: [PATCH 3/6] ath9k: Use tsf offset helper in ath9k_hw_reset

[Kalle Valo]

Benjamin Berg <benjamin@sipsolutions.net> writes:

> From: Benjamin Berg <benjamin.berg@open-mesh.com>
>
> Not much of a change. Only small fix is that we don't assume that
> exactly 1.5ms have passed for the second AR91xx SoC TSF setting.
>
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>

Why we don't need that 1.5 ms delta anymore? It would be good to
document that in the commit log in case someone else wonders why that
change was made.

-- 
Kalle Valo

[ath9k-devel] [PATCH 3/6] ath9k: Use tsf offset helper in ath9k_hw_reset

[Kalle Valo]

Benjamin Berg <benjamin@sipsolutions.net> writes:

> From: Benjamin Berg <benjamin.berg@open-mesh.com>
>
> Not much of a change. Only small fix is that we don't assume that
> exactly 1.5ms have passed for the second AR91xx SoC TSF setting.
>
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>

Why we don't need that 1.5 ms delta anymore? It would be good to
document that in the commit log in case someone else wonders why that
change was made.

-- 
Kalle Valo

[PATCH 4/6] ath9k: Expose tsf_adjustment in mac80211 tsf getters and setters.

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 375c2ac..f2ebc85 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1835,6 +1835,7 @@ static u64 ath9k_get_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 		tsf = sc->cur_chan->tsf_val +
 		      ath9k_hw_get_tsf_offset(&sc->cur_chan->tsf_ts, NULL);
 	}
+	tsf += le64_to_cpu(avp->tsf_adjust);
 	ath9k_ps_restore(sc);
 	mutex_unlock(&sc->mutex);
 
@@ -1850,6 +1851,7 @@ static void ath9k_set_tsf(struct ieee80211_hw *hw,
 
 	mutex_lock(&sc->mutex);
 	ath9k_ps_wakeup(sc);
+	tsf -= le64_to_cpu(avp->tsf_adjust);
 	getrawmonotonic(&avp->chanctx->tsf_ts);
 	if (sc->cur_chan == avp->chanctx)
 		ath9k_hw_settsf64(sc->sc_ah, tsf);
-- 
2.8.1

[ath9k-devel] [PATCH 4/6] ath9k: Expose tsf_adjustment in mac80211 tsf getters and setters.

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 375c2ac..f2ebc85 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1835,6 +1835,7 @@ static u64 ath9k_get_tsf(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 		tsf = sc->cur_chan->tsf_val +
 		      ath9k_hw_get_tsf_offset(&sc->cur_chan->tsf_ts, NULL);
 	}
+	tsf += le64_to_cpu(avp->tsf_adjust);
 	ath9k_ps_restore(sc);
 	mutex_unlock(&sc->mutex);
 
@@ -1850,6 +1851,7 @@ static void ath9k_set_tsf(struct ieee80211_hw *hw,
 
 	mutex_lock(&sc->mutex);
 	ath9k_ps_wakeup(sc);
+	tsf -= le64_to_cpu(avp->tsf_adjust);
 	getrawmonotonic(&avp->chanctx->tsf_ts);
 	if (sc->cur_chan == avp->chanctx)
 		ath9k_hw_settsf64(sc->sc_ah, tsf);
-- 
2.8.1

Re: [PATCH 4/6] ath9k: Expose tsf_adjustment in mac80211 tsf getters and setters.

[Kalle Valo]

Benjamin Berg <benjamin@sipsolutions.net> writes:

> From: Benjamin Berg <benjamin.berg@open-mesh.com>
>
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>

Why? Does this help with mesh or what?

Remember that the most important part of the commit log is to answer the
question "Why?".

-- 
Kalle Valo

[ath9k-devel] [PATCH 4/6] ath9k: Expose tsf_adjustment in mac80211 tsf getters and setters.

[Kalle Valo]

Benjamin Berg <benjamin@sipsolutions.net> writes:

> From: Benjamin Berg <benjamin.berg@open-mesh.com>
>
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>

Why? Does this help with mesh or what?

Remember that the most important part of the commit log is to answer the
question "Why?".

-- 
Kalle Valo

[PATCH 5/6] ath9k: Use defined constants consistently.

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/main.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index f2ebc85..6a81298 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1785,9 +1785,10 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 	if ((avp->chanctx == sc->cur_chan) &&
 	    (changed & BSS_CHANGED_ERP_SLOT)) {
 		if (bss_conf->use_short_slot)
-			slottime = 9;
+			slottime = ATH9K_SLOT_TIME_9;
 		else
-			slottime = 20;
+			slottime = ATH9K_SLOT_TIME_20;
+
 		if (vif->type == NL80211_IFTYPE_AP) {
 			/*
 			 * Defer update, so that connected stations can adjust
-- 
2.8.1

[ath9k-devel] [PATCH 5/6] ath9k: Use defined constants consistently.

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/main.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index f2ebc85..6a81298 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1785,9 +1785,10 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 	if ((avp->chanctx == sc->cur_chan) &&
 	    (changed & BSS_CHANGED_ERP_SLOT)) {
 		if (bss_conf->use_short_slot)
-			slottime = 9;
+			slottime = ATH9K_SLOT_TIME_9;
 		else
-			slottime = 20;
+			slottime = ATH9K_SLOT_TIME_20;
+
 		if (vif->type == NL80211_IFTYPE_AP) {
 			/*
 			 * Defer update, so that connected stations can adjust
-- 
2.8.1

Re: [PATCH 5/6] ath9k: Use defined constants consistently.

[Felix Fietkau]

On 2016-06-07 15:10, Benjamin Berg wrote:
> From: Benjamin Berg <benjamin.berg@open-mesh.com>
> 
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
> ---
>  drivers/net/wireless/ath/ath9k/main.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
> index f2ebc85..6a81298 100644
> --- a/drivers/net/wireless/ath/ath9k/main.c
> +++ b/drivers/net/wireless/ath/ath9k/main.c
> @@ -1785,9 +1785,10 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
>  	if ((avp->chanctx == sc->cur_chan) &&
>  	    (changed & BSS_CHANGED_ERP_SLOT)) {
>  		if (bss_conf->use_short_slot)
> -			slottime = 9;
> +			slottime = ATH9K_SLOT_TIME_9;
>  		else
> -			slottime = 20;
> +			slottime = ATH9K_SLOT_TIME_20;
Wouldn't it be better to just remove those pointless defines?

- Felix

[ath9k-devel] [PATCH 5/6] ath9k: Use defined constants consistently.

[Felix Fietkau]

On 2016-06-07 15:10, Benjamin Berg wrote:
> From: Benjamin Berg <benjamin.berg@open-mesh.com>
> 
> Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
> ---
>  drivers/net/wireless/ath/ath9k/main.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
> index f2ebc85..6a81298 100644
> --- a/drivers/net/wireless/ath/ath9k/main.c
> +++ b/drivers/net/wireless/ath/ath9k/main.c
> @@ -1785,9 +1785,10 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
>  	if ((avp->chanctx == sc->cur_chan) &&
>  	    (changed & BSS_CHANGED_ERP_SLOT)) {
>  		if (bss_conf->use_short_slot)
> -			slottime = 9;
> +			slottime = ATH9K_SLOT_TIME_9;
>  		else
> -			slottime = 20;
> +			slottime = ATH9K_SLOT_TIME_20;
Wouldn't it be better to just remove those pointless defines?

- Felix

[PATCH 6/6] ath9k: Fix beacon configuration for addition/removal of interfaces

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

This patch fixes some issues with interface reconfiguration. It could
for example happen that an AP interface in beacon slot 0 was removed
leaving an IBSS station in one of the other slots.

This patch approaches these failures by reconfiguring the beacon
configuration from calculate_summary_state instead of trying to
track whether the configuration should be modified.

The issue that a single non-AP interface might not be in beacon
slot 0 and wouldn't be send out is solved by moving it into the
first slot. The TSF value in hardware is adjusted accordingly so
that the timestamp of the beacons stay consistent.

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/ath9k.h  |   7 +-
 drivers/net/wireless/ath/ath9k/beacon.c | 240 ++++++++++++++++++--------------
 drivers/net/wireless/ath/ath9k/common.h |   1 +
 drivers/net/wireless/ath/ath9k/main.c   |  43 +++---
 4 files changed, 165 insertions(+), 126 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 93b3793..26fc8ec 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -637,6 +637,8 @@ struct ath9k_vif_iter_data {
 	int nwds;      /* number of WDS vifs */
 	int nadhocs;   /* number of adhoc vifs */
 	int nocbs;     /* number of OCB vifs */
+	int nbcnvifs;  /* number of beaconing vifs */
+	struct ieee80211_vif *primary_beacon_vif;
 	struct ieee80211_vif *primary_sta;
 };
 
@@ -685,10 +687,11 @@ struct ath_beacon {
 };
 
 void ath9k_beacon_tasklet(unsigned long data);
-void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif,
-			 u32 changed);
+void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *main_vif,
+			 bool beacons);
 void ath9k_beacon_assign_slot(struct ath_softc *sc, struct ieee80211_vif *vif);
 void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif);
+void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc);
 void ath9k_set_beacon(struct ath_softc *sc);
 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif);
 void ath9k_csa_update(struct ath_softc *sc);
diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 800c96b..0fa7ac2 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -209,7 +209,6 @@ void ath9k_beacon_assign_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 	}
 
 	sc->beacon.bslot[avp->av_bslot] = vif;
-	sc->nbcnvifs++;
 
 	ath_dbg(common, CONFIG, "Added interface at beacon slot: %d\n",
 		avp->av_bslot);
@@ -220,15 +219,12 @@ void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 	struct ath_vif *avp = (void *)vif->drv_priv;
 	struct ath_buf *bf = avp->av_bcbuf;
-	struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
 
 	ath_dbg(common, CONFIG, "Removing interface at beacon slot: %d\n",
 		avp->av_bslot);
 
 	tasklet_disable(&sc->bcon_tasklet);
 
-	cur_conf->enable_beacon &= ~BIT(avp->av_bslot);
-
 	if (bf && bf->bf_mpdu) {
 		struct sk_buff *skb = bf->bf_mpdu;
 		dma_unmap_single(sc->dev, bf->bf_buf_addr,
@@ -240,12 +236,73 @@ void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 
 	avp->av_bcbuf = NULL;
 	sc->beacon.bslot[avp->av_bslot] = NULL;
-	sc->nbcnvifs--;
 	list_add_tail(&bf->list, &sc->beacon.bbuf);
 
 	tasklet_enable(&sc->bcon_tasklet);
 }
 
+void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc)
+{
+	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+	struct ieee80211_vif *vif;
+	struct ath_vif *avp;
+	s64 tsfadjust;
+	u32 offset;
+	int first_slot = ATH_BCBUF;
+	int slot;
+
+	tasklet_disable(&sc->bcon_tasklet);
+
+	/* Find first taken slot. */
+	for (slot = 0; slot < ATH_BCBUF; slot++) {
+		if (sc->beacon.bslot[slot]) {
+			first_slot = slot;
+			break;
+		}
+	}
+	if (first_slot == 0)
+		goto out;
+
+	/* Re-enumarate all slots, moving them forward. */
+	for (slot = 0; slot < ATH_BCBUF; slot++) {
+		if (slot + first_slot < ATH_BCBUF) {
+			vif = sc->beacon.bslot[slot + first_slot];
+			sc->beacon.bslot[slot] = vif;
+
+			if (vif) {
+				avp = (void *)vif->drv_priv;
+				avp->av_bslot = slot;
+			}
+		} else {
+			sc->beacon.bslot[slot] = NULL;
+		}
+	}
+
+	vif = sc->beacon.bslot[0];
+	if (WARN_ON(!vif))
+		goto out;
+
+	/* Get the tsf_adjust value for the new first slot. */
+	avp = (void *)vif->drv_priv;
+	tsfadjust = le64_to_cpu(avp->tsf_adjust);
+
+	ath_dbg(common, CONFIG,
+		"Adjusting global TSF after beacon slot reassignment: %lld\n",
+		(signed long long)tsfadjust);
+
+	/* Modify TSF as required and update the HW. */
+	avp->chanctx->tsf_val += tsfadjust;
+	if (sc->cur_chan == avp->chanctx) {
+		offset = ath9k_hw_get_tsf_offset(&avp->chanctx->tsf_ts, NULL);
+		ath9k_hw_settsf64(sc->sc_ah, avp->chanctx->tsf_val + offset);
+	}
+
+	/* The slots tsf_adjust will be updated by ath9k_beacon_config later. */
+
+out:
+	tasklet_enable(&sc->bcon_tasklet);
+}
+
 static int ath9k_beacon_choose_slot(struct ath_softc *sc)
 {
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
@@ -274,26 +331,33 @@ static int ath9k_beacon_choose_slot(struct ath_softc *sc)
 	return slot;
 }
 
-static void ath9k_set_tsfadjust(struct ath_softc *sc, struct ieee80211_vif *vif)
+static void ath9k_set_tsfadjust(struct ath_softc *sc,
+				struct ath_beacon_config *cur_conf)
 {
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
-	struct ath_vif *avp = (void *)vif->drv_priv;
-	struct ath_beacon_config *cur_conf = &avp->chanctx->beacon;
 	s64 tsfadjust;
+	int slot;
 
-	if (avp->av_bslot == 0)
-		return;
+	for (slot = 0; slot < ATH_BCBUF; slot++) {
+		struct ath_vif *avp;
 
-	/* tsf_adjust is added to the TSF value. We send out the beacon late,
-	 * so need to adjust the TSF starting point to be later in time (i.e.
-	 * the theoretical first beacon has a TSF of 0 after correction).
-	 */
-	tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
-	tsfadjust = -TU_TO_USEC(tsfadjust) / ATH_BCBUF;
-	avp->tsf_adjust = cpu_to_le64(tsfadjust);
+		if (!sc->beacon.bslot[slot])
+			continue;
+
+		avp = (void *)sc->beacon.bslot[slot]->drv_priv;
 
-	ath_dbg(common, CONFIG, "tsfadjust is: %lld for bslot: %d\n",
-		(signed long long)tsfadjust, avp->av_bslot);
+		/* tsf_adjust is added to the TSF value. We send out the
+		 * beacon late, so need to adjust the TSF starting point to be
+		 * later in time (i.e. the theoretical first beacon has a TSF
+		 * of 0 after correction).
+		 */
+		tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
+		tsfadjust = -TU_TO_USEC(tsfadjust) / ATH_BCBUF;
+		avp->tsf_adjust = cpu_to_le64(tsfadjust);
+
+		ath_dbg(common, CONFIG, "tsfadjust is: %lld for bslot: %d\n",
+			(signed long long)tsfadjust, avp->av_bslot);
+	}
 }
 
 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif)
@@ -447,20 +511,28 @@ void ath9k_beacon_tasklet(unsigned long data)
  * Both nexttbtt and intval have to be in usecs.
  */
 static void ath9k_beacon_init(struct ath_softc *sc, u32 nexttbtt,
-			      u32 intval, bool reset_tsf)
+			      u32 intval)
 {
 	struct ath_hw *ah = sc->sc_ah;
 
 	ath9k_hw_disable_interrupts(ah);
-	if (reset_tsf)
-		ath9k_hw_reset_tsf(ah);
 	ath9k_beaconq_config(sc);
 	ath9k_hw_beaconinit(ah, nexttbtt, intval);
+	ah->imask |= ATH9K_INT_SWBA;
 	sc->beacon.bmisscnt = 0;
 	ath9k_hw_set_interrupts(ah);
 	ath9k_hw_enable_interrupts(ah);
 }
 
+static void ath9k_beacon_stop(struct ath_softc *sc)
+{
+	ath9k_hw_disable_interrupts(sc->sc_ah);
+	sc->sc_ah->imask &= ~(ATH9K_INT_SWBA | ATH9K_INT_BMISS);
+	sc->beacon.bmisscnt = 0;
+	ath9k_hw_set_interrupts(sc->sc_ah);
+	ath9k_hw_enable_interrupts(sc->sc_ah);
+}
+
 /*
  * For multi-bss ap support beacons are either staggered evenly over N slots or
  * burst together.  For the former arrange for the SWBA to be delivered for each
@@ -472,7 +544,7 @@ static void ath9k_beacon_config_ap(struct ath_softc *sc,
 	struct ath_hw *ah = sc->sc_ah;
 
 	ath9k_cmn_beacon_config_ap(ah, conf, ATH_BCBUF);
-	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, false);
+	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval);
 }
 
 static void ath9k_beacon_config_sta(struct ath_hw *ah,
@@ -501,7 +573,7 @@ static void ath9k_beacon_config_adhoc(struct ath_softc *sc,
 
 	ath9k_cmn_beacon_config_adhoc(ah, conf);
 
-	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, conf->ibss_creator);
+	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval);
 
 	/*
 	 * Set the global 'beacon has been configured' flag for the
@@ -511,44 +583,6 @@ static void ath9k_beacon_config_adhoc(struct ath_softc *sc,
 		set_bit(ATH_OP_BEACONS, &common->op_flags);
 }
 
-static bool ath9k_allow_beacon_config(struct ath_softc *sc,
-				      struct ieee80211_vif *vif)
-{
-	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
-	struct ath_vif *avp = (void *)vif->drv_priv;
-
-	if (ath9k_is_chanctx_enabled()) {
-		/*
-		 * If the VIF is not present in the current channel context,
-		 * then we can't do the usual opmode checks. Allow the
-		 * beacon config for the VIF to be updated in this case and
-		 * return immediately.
-		 */
-		if (sc->cur_chan != avp->chanctx)
-			return true;
-	}
-
-	if (sc->sc_ah->opmode == NL80211_IFTYPE_AP) {
-		if (vif->type != NL80211_IFTYPE_AP) {
-			ath_dbg(common, CONFIG,
-				"An AP interface is already present !\n");
-			return false;
-		}
-	}
-
-	if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
-		if ((vif->type == NL80211_IFTYPE_STATION) &&
-		    test_bit(ATH_OP_BEACONS, &common->op_flags) &&
-		    vif != sc->cur_chan->primary_sta) {
-			ath_dbg(common, CONFIG,
-				"Beacon already configured for a station interface\n");
-			return false;
-		}
-	}
-
-	return true;
-}
-
 static void ath9k_cache_beacon_config(struct ath_softc *sc,
 				      struct ath_chanctx *ctx,
 				      struct ieee80211_bss_conf *bss_conf)
@@ -584,87 +618,79 @@ static void ath9k_cache_beacon_config(struct ath_softc *sc,
 	if (cur_conf->dtim_period == 0)
 		cur_conf->dtim_period = 1;
 
+	ath9k_set_tsfadjust(sc, cur_conf);
 }
 
-void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif,
-			 u32 changed)
+void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *main_vif,
+			 bool beacons)
 {
-	struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
-        struct ath_hw *ah = sc->sc_ah;
-        struct ath_common *common = ath9k_hw_common(ah);
-	struct ath_vif *avp = (void *)vif->drv_priv;
-	struct ath_chanctx *ctx = avp->chanctx;
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_common *common = ath9k_hw_common(ah);
+	struct ath_vif *avp;
+	struct ath_chanctx *ctx;
 	struct ath_beacon_config *cur_conf;
 	unsigned long flags;
+	bool enabled;
 	bool skip_beacon = false;
 
-	if (!ctx)
+	if (!beacons) {
+		clear_bit(ATH_OP_BEACONS, &common->op_flags);
+		ath9k_beacon_stop(sc);
 		return;
+	}
 
-	cur_conf = &avp->chanctx->beacon;
-	if (vif->type == NL80211_IFTYPE_AP)
-		ath9k_set_tsfadjust(sc, vif);
-
-	if (!ath9k_allow_beacon_config(sc, vif))
+	if (WARN_ON(!main_vif))
 		return;
 
-	if (vif->type == NL80211_IFTYPE_STATION) {
-		ath9k_cache_beacon_config(sc, ctx, bss_conf);
-		if (ctx != sc->cur_chan)
-			return;
+	avp = (void *)main_vif->drv_priv;
+	ctx = avp->chanctx;
+	cur_conf = &ctx->beacon;
+	enabled = cur_conf->enable_beacon;
+	cur_conf->enable_beacon = beacons;
+
+	if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
+		ath9k_cache_beacon_config(sc, ctx, &main_vif->bss_conf);
 
 		ath9k_set_beacon(sc);
 		set_bit(ATH_OP_BEACONS, &common->op_flags);
 		return;
 	}
 
-	/*
-	 * Take care of multiple interfaces when
-	 * enabling/disabling SWBA.
-	 */
-	if (changed & BSS_CHANGED_BEACON_ENABLED) {
-		bool enabled = cur_conf->enable_beacon;
-
-		if (!bss_conf->enable_beacon) {
-			cur_conf->enable_beacon &= ~BIT(avp->av_bslot);
-		} else {
-			cur_conf->enable_beacon |= BIT(avp->av_bslot);
-			if (!enabled)
-				ath9k_cache_beacon_config(sc, ctx, bss_conf);
-		}
-	}
-
-	if (ctx != sc->cur_chan)
-		return;
+	/* Update the beacon configuration. */
+	ath9k_cache_beacon_config(sc, ctx, &main_vif->bss_conf);
 
 	/*
 	 * Configure the HW beacon registers only when we have a valid
 	 * beacon interval.
 	 */
 	if (cur_conf->beacon_interval) {
-		/*
-		 * If we are joining an existing IBSS network, start beaconing
-		 * only after a TSF-sync has taken place. Ensure that this
-		 * happens by setting the appropriate flags.
+		/* Special case to sync the TSF when joining an existing IBSS.
+		 * This is only done if no AP interface is active.
+		 * Note that mac80211 always resets the TSF when creating a new
+		 * IBSS interface.
 		 */
-		if ((changed & BSS_CHANGED_IBSS) && !bss_conf->ibss_creator &&
-		    bss_conf->enable_beacon) {
+		if (sc->sc_ah->opmode == NL80211_IFTYPE_ADHOC &&
+		    !enabled && beacons && !main_vif->bss_conf.ibss_creator) {
 			spin_lock_irqsave(&sc->sc_pm_lock, flags);
 			sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
 			spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 			skip_beacon = true;
-		} else {
-			ath9k_set_beacon(sc);
 		}
 
 		/*
 		 * Do not set the ATH_OP_BEACONS flag for IBSS joiner mode
 		 * here, it is done in ath9k_beacon_config_adhoc().
 		 */
-		if (cur_conf->enable_beacon && !skip_beacon)
+		if (beacons && !skip_beacon) {
 			set_bit(ATH_OP_BEACONS, &common->op_flags);
-		else
+			ath9k_set_beacon(sc);
+		} else {
 			clear_bit(ATH_OP_BEACONS, &common->op_flags);
+			ath9k_beacon_stop(sc);
+		}
+	} else {
+		clear_bit(ATH_OP_BEACONS, &common->op_flags);
+		ath9k_beacon_stop(sc);
 	}
 }
 
diff --git a/drivers/net/wireless/ath/ath9k/common.h b/drivers/net/wireless/ath/ath9k/common.h
index d237373..f0ab6f9 100644
--- a/drivers/net/wireless/ath/ath9k/common.h
+++ b/drivers/net/wireless/ath/ath9k/common.h
@@ -50,6 +50,7 @@
 #define IEEE80211_MS_TO_TU(x)   (((x) * 1000) / 1024)
 
 struct ath_beacon_config {
+	struct ieee80211_vif *main_vif;
 	int beacon_interval;
 	u16 dtim_period;
 	u16 bmiss_timeout;
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 6a81298..a8a959d 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -910,6 +910,22 @@ static bool ath9k_uses_beacons(int type)
 	}
 }
 
+static void ath9k_vif_iter_set_beacon(struct ath9k_vif_iter_data *iter_data,
+				      struct ieee80211_vif *vif)
+{
+	/* Use the first (configured) interface, but prefering AP interfaces. */
+	if (!iter_data->primary_beacon_vif) {
+		iter_data->primary_beacon_vif = vif;
+	} else {
+		if (iter_data->primary_beacon_vif->type != NL80211_IFTYPE_AP &&
+		    vif->type == NL80211_IFTYPE_AP)
+		iter_data->primary_beacon_vif = vif;
+	}
+
+	iter_data->beacons = true;
+	iter_data->nbcnvifs += 1;
+}
+
 static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data,
 			   u8 *mac, struct ieee80211_vif *vif)
 {
@@ -931,6 +947,8 @@ static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data,
 	switch (vif->type) {
 	case NL80211_IFTYPE_AP:
 		iter_data->naps++;
+		if (vif->bss_conf.enable_beacon)
+			ath9k_vif_iter_set_beacon(iter_data, vif);
 		break;
 	case NL80211_IFTYPE_STATION:
 		iter_data->nstations++;
@@ -943,12 +961,12 @@ static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data,
 	case NL80211_IFTYPE_ADHOC:
 		iter_data->nadhocs++;
 		if (vif->bss_conf.enable_beacon)
-			iter_data->beacons = true;
+			ath9k_vif_iter_set_beacon(iter_data, vif);
 		break;
 	case NL80211_IFTYPE_MESH_POINT:
 		iter_data->nmeshes++;
 		if (vif->bss_conf.enable_beacon)
-			iter_data->beacons = true;
+			ath9k_vif_iter_set_beacon(iter_data, vif);
 		break;
 	case NL80211_IFTYPE_WDS:
 		iter_data->nwds++;
@@ -1081,7 +1099,6 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
 	struct ath9k_vif_iter_data iter_data;
-	struct ath_beacon_config *cur_conf;
 
 	ath_chanctx_check_active(sc, ctx);
 
@@ -1103,13 +1120,12 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 	ath_hw_setbssidmask(common);
 
 	if (iter_data.naps > 0) {
-		cur_conf = &ctx->beacon;
 		ath9k_hw_set_tsfadjust(ah, true);
 		ah->opmode = NL80211_IFTYPE_AP;
-		if (cur_conf->enable_beacon)
-			iter_data.beacons = true;
 	} else {
 		ath9k_hw_set_tsfadjust(ah, false);
+		if (iter_data.beacons)
+			ath9k_beacon_ensure_primary_slot(sc);
 
 		if (iter_data.nmeshes)
 			ah->opmode = NL80211_IFTYPE_MESH_POINT;
@@ -1134,7 +1150,6 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 			ctx->switch_after_beacon = true;
 	}
 
-	ah->imask &= ~ATH9K_INT_SWBA;
 	if (ah->opmode == NL80211_IFTYPE_STATION) {
 		bool changed = (iter_data.primary_sta != ctx->primary_sta);
 
@@ -1151,16 +1166,12 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 			if (ath9k_hw_mci_is_enabled(sc->sc_ah))
 				ath9k_mci_update_wlan_channels(sc, true);
 		}
-	} else if (iter_data.beacons) {
-		ah->imask |= ATH9K_INT_SWBA;
 	}
+	sc->nbcnvifs = iter_data.nbcnvifs;
+	ath9k_beacon_config(sc, iter_data.primary_beacon_vif,
+			    iter_data.beacons);
 	ath9k_hw_set_interrupts(ah);
 
-	if (iter_data.beacons)
-		set_bit(ATH_OP_BEACONS, &common->op_flags);
-	else
-		clear_bit(ATH_OP_BEACONS, &common->op_flags);
-
 	if (ah->slottime != iter_data.slottime) {
 		ah->slottime = iter_data.slottime;
 		ath9k_hw_init_global_settings(ah);
@@ -1777,9 +1788,7 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 	if ((changed & BSS_CHANGED_BEACON_ENABLED) ||
 	    (changed & BSS_CHANGED_BEACON_INT) ||
 	    (changed & BSS_CHANGED_BEACON_INFO)) {
-		ath9k_beacon_config(sc, vif, changed);
-		if (changed & BSS_CHANGED_BEACON_ENABLED)
-			ath9k_calculate_summary_state(sc, avp->chanctx);
+		ath9k_calculate_summary_state(sc, avp->chanctx);
 	}
 
 	if ((avp->chanctx == sc->cur_chan) &&
-- 
2.8.1

[ath9k-devel] [PATCH 6/6] ath9k: Fix beacon configuration for addition/removal of interfaces

[Benjamin Berg]

From: Benjamin Berg <benjamin.berg@open-mesh.com>

This patch fixes some issues with interface reconfiguration. It could
for example happen that an AP interface in beacon slot 0 was removed
leaving an IBSS station in one of the other slots.

This patch approaches these failures by reconfiguring the beacon
configuration from calculate_summary_state instead of trying to
track whether the configuration should be modified.

The issue that a single non-AP interface might not be in beacon
slot 0 and wouldn't be send out is solved by moving it into the
first slot. The TSF value in hardware is adjusted accordingly so
that the timestamp of the beacons stay consistent.

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
---
 drivers/net/wireless/ath/ath9k/ath9k.h  |   7 +-
 drivers/net/wireless/ath/ath9k/beacon.c | 240 ++++++++++++++++++--------------
 drivers/net/wireless/ath/ath9k/common.h |   1 +
 drivers/net/wireless/ath/ath9k/main.c   |  43 +++---
 4 files changed, 165 insertions(+), 126 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 93b3793..26fc8ec 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -637,6 +637,8 @@ struct ath9k_vif_iter_data {
 	int nwds;      /* number of WDS vifs */
 	int nadhocs;   /* number of adhoc vifs */
 	int nocbs;     /* number of OCB vifs */
+	int nbcnvifs;  /* number of beaconing vifs */
+	struct ieee80211_vif *primary_beacon_vif;
 	struct ieee80211_vif *primary_sta;
 };
 
@@ -685,10 +687,11 @@ struct ath_beacon {
 };
 
 void ath9k_beacon_tasklet(unsigned long data);
-void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif,
-			 u32 changed);
+void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *main_vif,
+			 bool beacons);
 void ath9k_beacon_assign_slot(struct ath_softc *sc, struct ieee80211_vif *vif);
 void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif);
+void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc);
 void ath9k_set_beacon(struct ath_softc *sc);
 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif);
 void ath9k_csa_update(struct ath_softc *sc);
diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 800c96b..0fa7ac2 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -209,7 +209,6 @@ void ath9k_beacon_assign_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 	}
 
 	sc->beacon.bslot[avp->av_bslot] = vif;
-	sc->nbcnvifs++;
 
 	ath_dbg(common, CONFIG, "Added interface at beacon slot: %d\n",
 		avp->av_bslot);
@@ -220,15 +219,12 @@ void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 	struct ath_vif *avp = (void *)vif->drv_priv;
 	struct ath_buf *bf = avp->av_bcbuf;
-	struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
 
 	ath_dbg(common, CONFIG, "Removing interface at beacon slot: %d\n",
 		avp->av_bslot);
 
 	tasklet_disable(&sc->bcon_tasklet);
 
-	cur_conf->enable_beacon &= ~BIT(avp->av_bslot);
-
 	if (bf && bf->bf_mpdu) {
 		struct sk_buff *skb = bf->bf_mpdu;
 		dma_unmap_single(sc->dev, bf->bf_buf_addr,
@@ -240,12 +236,73 @@ void ath9k_beacon_remove_slot(struct ath_softc *sc, struct ieee80211_vif *vif)
 
 	avp->av_bcbuf = NULL;
 	sc->beacon.bslot[avp->av_bslot] = NULL;
-	sc->nbcnvifs--;
 	list_add_tail(&bf->list, &sc->beacon.bbuf);
 
 	tasklet_enable(&sc->bcon_tasklet);
 }
 
+void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc)
+{
+	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+	struct ieee80211_vif *vif;
+	struct ath_vif *avp;
+	s64 tsfadjust;
+	u32 offset;
+	int first_slot = ATH_BCBUF;
+	int slot;
+
+	tasklet_disable(&sc->bcon_tasklet);
+
+	/* Find first taken slot. */
+	for (slot = 0; slot < ATH_BCBUF; slot++) {
+		if (sc->beacon.bslot[slot]) {
+			first_slot = slot;
+			break;
+		}
+	}
+	if (first_slot == 0)
+		goto out;
+
+	/* Re-enumarate all slots, moving them forward. */
+	for (slot = 0; slot < ATH_BCBUF; slot++) {
+		if (slot + first_slot < ATH_BCBUF) {
+			vif = sc->beacon.bslot[slot + first_slot];
+			sc->beacon.bslot[slot] = vif;
+
+			if (vif) {
+				avp = (void *)vif->drv_priv;
+				avp->av_bslot = slot;
+			}
+		} else {
+			sc->beacon.bslot[slot] = NULL;
+		}
+	}
+
+	vif = sc->beacon.bslot[0];
+	if (WARN_ON(!vif))
+		goto out;
+
+	/* Get the tsf_adjust value for the new first slot. */
+	avp = (void *)vif->drv_priv;
+	tsfadjust = le64_to_cpu(avp->tsf_adjust);
+
+	ath_dbg(common, CONFIG,
+		"Adjusting global TSF after beacon slot reassignment: %lld\n",
+		(signed long long)tsfadjust);
+
+	/* Modify TSF as required and update the HW. */
+	avp->chanctx->tsf_val += tsfadjust;
+	if (sc->cur_chan == avp->chanctx) {
+		offset = ath9k_hw_get_tsf_offset(&avp->chanctx->tsf_ts, NULL);
+		ath9k_hw_settsf64(sc->sc_ah, avp->chanctx->tsf_val + offset);
+	}
+
+	/* The slots tsf_adjust will be updated by ath9k_beacon_config later. */
+
+out:
+	tasklet_enable(&sc->bcon_tasklet);
+}
+
 static int ath9k_beacon_choose_slot(struct ath_softc *sc)
 {
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
@@ -274,26 +331,33 @@ static int ath9k_beacon_choose_slot(struct ath_softc *sc)
 	return slot;
 }
 
-static void ath9k_set_tsfadjust(struct ath_softc *sc, struct ieee80211_vif *vif)
+static void ath9k_set_tsfadjust(struct ath_softc *sc,
+				struct ath_beacon_config *cur_conf)
 {
 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
-	struct ath_vif *avp = (void *)vif->drv_priv;
-	struct ath_beacon_config *cur_conf = &avp->chanctx->beacon;
 	s64 tsfadjust;
+	int slot;
 
-	if (avp->av_bslot == 0)
-		return;
+	for (slot = 0; slot < ATH_BCBUF; slot++) {
+		struct ath_vif *avp;
 
-	/* tsf_adjust is added to the TSF value. We send out the beacon late,
-	 * so need to adjust the TSF starting point to be later in time (i.e.
-	 * the theoretical first beacon has a TSF of 0 after correction).
-	 */
-	tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
-	tsfadjust = -TU_TO_USEC(tsfadjust) / ATH_BCBUF;
-	avp->tsf_adjust = cpu_to_le64(tsfadjust);
+		if (!sc->beacon.bslot[slot])
+			continue;
+
+		avp = (void *)sc->beacon.bslot[slot]->drv_priv;
 
-	ath_dbg(common, CONFIG, "tsfadjust is: %lld for bslot: %d\n",
-		(signed long long)tsfadjust, avp->av_bslot);
+		/* tsf_adjust is added to the TSF value. We send out the
+		 * beacon late, so need to adjust the TSF starting point to be
+		 * later in time (i.e. the theoretical first beacon has a TSF
+		 * of 0 after correction).
+		 */
+		tsfadjust = cur_conf->beacon_interval * avp->av_bslot;
+		tsfadjust = -TU_TO_USEC(tsfadjust) / ATH_BCBUF;
+		avp->tsf_adjust = cpu_to_le64(tsfadjust);
+
+		ath_dbg(common, CONFIG, "tsfadjust is: %lld for bslot: %d\n",
+			(signed long long)tsfadjust, avp->av_bslot);
+	}
 }
 
 bool ath9k_csa_is_finished(struct ath_softc *sc, struct ieee80211_vif *vif)
@@ -447,20 +511,28 @@ void ath9k_beacon_tasklet(unsigned long data)
  * Both nexttbtt and intval have to be in usecs.
  */
 static void ath9k_beacon_init(struct ath_softc *sc, u32 nexttbtt,
-			      u32 intval, bool reset_tsf)
+			      u32 intval)
 {
 	struct ath_hw *ah = sc->sc_ah;
 
 	ath9k_hw_disable_interrupts(ah);
-	if (reset_tsf)
-		ath9k_hw_reset_tsf(ah);
 	ath9k_beaconq_config(sc);
 	ath9k_hw_beaconinit(ah, nexttbtt, intval);
+	ah->imask |= ATH9K_INT_SWBA;
 	sc->beacon.bmisscnt = 0;
 	ath9k_hw_set_interrupts(ah);
 	ath9k_hw_enable_interrupts(ah);
 }
 
+static void ath9k_beacon_stop(struct ath_softc *sc)
+{
+	ath9k_hw_disable_interrupts(sc->sc_ah);
+	sc->sc_ah->imask &= ~(ATH9K_INT_SWBA | ATH9K_INT_BMISS);
+	sc->beacon.bmisscnt = 0;
+	ath9k_hw_set_interrupts(sc->sc_ah);
+	ath9k_hw_enable_interrupts(sc->sc_ah);
+}
+
 /*
  * For multi-bss ap support beacons are either staggered evenly over N slots or
  * burst together.  For the former arrange for the SWBA to be delivered for each
@@ -472,7 +544,7 @@ static void ath9k_beacon_config_ap(struct ath_softc *sc,
 	struct ath_hw *ah = sc->sc_ah;
 
 	ath9k_cmn_beacon_config_ap(ah, conf, ATH_BCBUF);
-	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, false);
+	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval);
 }
 
 static void ath9k_beacon_config_sta(struct ath_hw *ah,
@@ -501,7 +573,7 @@ static void ath9k_beacon_config_adhoc(struct ath_softc *sc,
 
 	ath9k_cmn_beacon_config_adhoc(ah, conf);
 
-	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval, conf->ibss_creator);
+	ath9k_beacon_init(sc, conf->nexttbtt, conf->intval);
 
 	/*
 	 * Set the global 'beacon has been configured' flag for the
@@ -511,44 +583,6 @@ static void ath9k_beacon_config_adhoc(struct ath_softc *sc,
 		set_bit(ATH_OP_BEACONS, &common->op_flags);
 }
 
-static bool ath9k_allow_beacon_config(struct ath_softc *sc,
-				      struct ieee80211_vif *vif)
-{
-	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
-	struct ath_vif *avp = (void *)vif->drv_priv;
-
-	if (ath9k_is_chanctx_enabled()) {
-		/*
-		 * If the VIF is not present in the current channel context,
-		 * then we can't do the usual opmode checks. Allow the
-		 * beacon config for the VIF to be updated in this case and
-		 * return immediately.
-		 */
-		if (sc->cur_chan != avp->chanctx)
-			return true;
-	}
-
-	if (sc->sc_ah->opmode == NL80211_IFTYPE_AP) {
-		if (vif->type != NL80211_IFTYPE_AP) {
-			ath_dbg(common, CONFIG,
-				"An AP interface is already present !\n");
-			return false;
-		}
-	}
-
-	if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
-		if ((vif->type == NL80211_IFTYPE_STATION) &&
-		    test_bit(ATH_OP_BEACONS, &common->op_flags) &&
-		    vif != sc->cur_chan->primary_sta) {
-			ath_dbg(common, CONFIG,
-				"Beacon already configured for a station interface\n");
-			return false;
-		}
-	}
-
-	return true;
-}
-
 static void ath9k_cache_beacon_config(struct ath_softc *sc,
 				      struct ath_chanctx *ctx,
 				      struct ieee80211_bss_conf *bss_conf)
@@ -584,87 +618,79 @@ static void ath9k_cache_beacon_config(struct ath_softc *sc,
 	if (cur_conf->dtim_period == 0)
 		cur_conf->dtim_period = 1;
 
+	ath9k_set_tsfadjust(sc, cur_conf);
 }
 
-void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif,
-			 u32 changed)
+void ath9k_beacon_config(struct ath_softc *sc, struct ieee80211_vif *main_vif,
+			 bool beacons)
 {
-	struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
-        struct ath_hw *ah = sc->sc_ah;
-        struct ath_common *common = ath9k_hw_common(ah);
-	struct ath_vif *avp = (void *)vif->drv_priv;
-	struct ath_chanctx *ctx = avp->chanctx;
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_common *common = ath9k_hw_common(ah);
+	struct ath_vif *avp;
+	struct ath_chanctx *ctx;
 	struct ath_beacon_config *cur_conf;
 	unsigned long flags;
+	bool enabled;
 	bool skip_beacon = false;
 
-	if (!ctx)
+	if (!beacons) {
+		clear_bit(ATH_OP_BEACONS, &common->op_flags);
+		ath9k_beacon_stop(sc);
 		return;
+	}
 
-	cur_conf = &avp->chanctx->beacon;
-	if (vif->type == NL80211_IFTYPE_AP)
-		ath9k_set_tsfadjust(sc, vif);
-
-	if (!ath9k_allow_beacon_config(sc, vif))
+	if (WARN_ON(!main_vif))
 		return;
 
-	if (vif->type == NL80211_IFTYPE_STATION) {
-		ath9k_cache_beacon_config(sc, ctx, bss_conf);
-		if (ctx != sc->cur_chan)
-			return;
+	avp = (void *)main_vif->drv_priv;
+	ctx = avp->chanctx;
+	cur_conf = &ctx->beacon;
+	enabled = cur_conf->enable_beacon;
+	cur_conf->enable_beacon = beacons;
+
+	if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION) {
+		ath9k_cache_beacon_config(sc, ctx, &main_vif->bss_conf);
 
 		ath9k_set_beacon(sc);
 		set_bit(ATH_OP_BEACONS, &common->op_flags);
 		return;
 	}
 
-	/*
-	 * Take care of multiple interfaces when
-	 * enabling/disabling SWBA.
-	 */
-	if (changed & BSS_CHANGED_BEACON_ENABLED) {
-		bool enabled = cur_conf->enable_beacon;
-
-		if (!bss_conf->enable_beacon) {
-			cur_conf->enable_beacon &= ~BIT(avp->av_bslot);
-		} else {
-			cur_conf->enable_beacon |= BIT(avp->av_bslot);
-			if (!enabled)
-				ath9k_cache_beacon_config(sc, ctx, bss_conf);
-		}
-	}
-
-	if (ctx != sc->cur_chan)
-		return;
+	/* Update the beacon configuration. */
+	ath9k_cache_beacon_config(sc, ctx, &main_vif->bss_conf);
 
 	/*
 	 * Configure the HW beacon registers only when we have a valid
 	 * beacon interval.
 	 */
 	if (cur_conf->beacon_interval) {
-		/*
-		 * If we are joining an existing IBSS network, start beaconing
-		 * only after a TSF-sync has taken place. Ensure that this
-		 * happens by setting the appropriate flags.
+		/* Special case to sync the TSF when joining an existing IBSS.
+		 * This is only done if no AP interface is active.
+		 * Note that mac80211 always resets the TSF when creating a new
+		 * IBSS interface.
 		 */
-		if ((changed & BSS_CHANGED_IBSS) && !bss_conf->ibss_creator &&
-		    bss_conf->enable_beacon) {
+		if (sc->sc_ah->opmode == NL80211_IFTYPE_ADHOC &&
+		    !enabled && beacons && !main_vif->bss_conf.ibss_creator) {
 			spin_lock_irqsave(&sc->sc_pm_lock, flags);
 			sc->ps_flags |= PS_BEACON_SYNC | PS_WAIT_FOR_BEACON;
 			spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
 			skip_beacon = true;
-		} else {
-			ath9k_set_beacon(sc);
 		}
 
 		/*
 		 * Do not set the ATH_OP_BEACONS flag for IBSS joiner mode
 		 * here, it is done in ath9k_beacon_config_adhoc().
 		 */
-		if (cur_conf->enable_beacon && !skip_beacon)
+		if (beacons && !skip_beacon) {
 			set_bit(ATH_OP_BEACONS, &common->op_flags);
-		else
+			ath9k_set_beacon(sc);
+		} else {
 			clear_bit(ATH_OP_BEACONS, &common->op_flags);
+			ath9k_beacon_stop(sc);
+		}
+	} else {
+		clear_bit(ATH_OP_BEACONS, &common->op_flags);
+		ath9k_beacon_stop(sc);
 	}
 }
 
diff --git a/drivers/net/wireless/ath/ath9k/common.h b/drivers/net/wireless/ath/ath9k/common.h
index d237373..f0ab6f9 100644
--- a/drivers/net/wireless/ath/ath9k/common.h
+++ b/drivers/net/wireless/ath/ath9k/common.h
@@ -50,6 +50,7 @@
 #define IEEE80211_MS_TO_TU(x)   (((x) * 1000) / 1024)
 
 struct ath_beacon_config {
+	struct ieee80211_vif *main_vif;
 	int beacon_interval;
 	u16 dtim_period;
 	u16 bmiss_timeout;
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 6a81298..a8a959d 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -910,6 +910,22 @@ static bool ath9k_uses_beacons(int type)
 	}
 }
 
+static void ath9k_vif_iter_set_beacon(struct ath9k_vif_iter_data *iter_data,
+				      struct ieee80211_vif *vif)
+{
+	/* Use the first (configured) interface, but prefering AP interfaces. */
+	if (!iter_data->primary_beacon_vif) {
+		iter_data->primary_beacon_vif = vif;
+	} else {
+		if (iter_data->primary_beacon_vif->type != NL80211_IFTYPE_AP &&
+		    vif->type == NL80211_IFTYPE_AP)
+		iter_data->primary_beacon_vif = vif;
+	}
+
+	iter_data->beacons = true;
+	iter_data->nbcnvifs += 1;
+}
+
 static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data,
 			   u8 *mac, struct ieee80211_vif *vif)
 {
@@ -931,6 +947,8 @@ static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data,
 	switch (vif->type) {
 	case NL80211_IFTYPE_AP:
 		iter_data->naps++;
+		if (vif->bss_conf.enable_beacon)
+			ath9k_vif_iter_set_beacon(iter_data, vif);
 		break;
 	case NL80211_IFTYPE_STATION:
 		iter_data->nstations++;
@@ -943,12 +961,12 @@ static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data,
 	case NL80211_IFTYPE_ADHOC:
 		iter_data->nadhocs++;
 		if (vif->bss_conf.enable_beacon)
-			iter_data->beacons = true;
+			ath9k_vif_iter_set_beacon(iter_data, vif);
 		break;
 	case NL80211_IFTYPE_MESH_POINT:
 		iter_data->nmeshes++;
 		if (vif->bss_conf.enable_beacon)
-			iter_data->beacons = true;
+			ath9k_vif_iter_set_beacon(iter_data, vif);
 		break;
 	case NL80211_IFTYPE_WDS:
 		iter_data->nwds++;
@@ -1081,7 +1099,6 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
 	struct ath9k_vif_iter_data iter_data;
-	struct ath_beacon_config *cur_conf;
 
 	ath_chanctx_check_active(sc, ctx);
 
@@ -1103,13 +1120,12 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 	ath_hw_setbssidmask(common);
 
 	if (iter_data.naps > 0) {
-		cur_conf = &ctx->beacon;
 		ath9k_hw_set_tsfadjust(ah, true);
 		ah->opmode = NL80211_IFTYPE_AP;
-		if (cur_conf->enable_beacon)
-			iter_data.beacons = true;
 	} else {
 		ath9k_hw_set_tsfadjust(ah, false);
+		if (iter_data.beacons)
+			ath9k_beacon_ensure_primary_slot(sc);
 
 		if (iter_data.nmeshes)
 			ah->opmode = NL80211_IFTYPE_MESH_POINT;
@@ -1134,7 +1150,6 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 			ctx->switch_after_beacon = true;
 	}
 
-	ah->imask &= ~ATH9K_INT_SWBA;
 	if (ah->opmode == NL80211_IFTYPE_STATION) {
 		bool changed = (iter_data.primary_sta != ctx->primary_sta);
 
@@ -1151,16 +1166,12 @@ void ath9k_calculate_summary_state(struct ath_softc *sc,
 			if (ath9k_hw_mci_is_enabled(sc->sc_ah))
 				ath9k_mci_update_wlan_channels(sc, true);
 		}
-	} else if (iter_data.beacons) {
-		ah->imask |= ATH9K_INT_SWBA;
 	}
+	sc->nbcnvifs = iter_data.nbcnvifs;
+	ath9k_beacon_config(sc, iter_data.primary_beacon_vif,
+			    iter_data.beacons);
 	ath9k_hw_set_interrupts(ah);
 
-	if (iter_data.beacons)
-		set_bit(ATH_OP_BEACONS, &common->op_flags);
-	else
-		clear_bit(ATH_OP_BEACONS, &common->op_flags);
-
 	if (ah->slottime != iter_data.slottime) {
 		ah->slottime = iter_data.slottime;
 		ath9k_hw_init_global_settings(ah);
@@ -1777,9 +1788,7 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
 	if ((changed & BSS_CHANGED_BEACON_ENABLED) ||
 	    (changed & BSS_CHANGED_BEACON_INT) ||
 	    (changed & BSS_CHANGED_BEACON_INFO)) {
-		ath9k_beacon_config(sc, vif, changed);
-		if (changed & BSS_CHANGED_BEACON_ENABLED)
-			ath9k_calculate_summary_state(sc, avp->chanctx);
+		ath9k_calculate_summary_state(sc, avp->chanctx);
 	}
 
 	if ((avp->chanctx == sc->cur_chan) &&
-- 
2.8.1