2016-07-04 12:38:06

by Benjamin Berg

[permalink] [raw]
Subject: [PATCH v2 1/6] ath9k: Correct TSF adjustment to align the beacon time correctly

From: Benjamin Berg <[email protected]>

Beacons were not send out at (timestamp % beacon_time == 0) for interfaces
other than the primary one. To send out beacons with the correct timestamp
according to 10.1.3.2 of the 802.11 standard the tsf_adjustment has to be
set to the negative time difference instead of positive. This way the
later beacons get corrected to have a lower (and similar) timestamp with
regard to the beacon from slot 0.

I am not aware about any issues that have been caused by this.

Signed-off-by: Benjamin Berg <[email protected]>
---
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



2016-07-04 12:38:04

by Benjamin Berg

[permalink] [raw]
Subject: [PATCH v2 2/6] ath9k: Handle channel context in get_/set_/reset_tsf

From: Benjamin Berg <[email protected]>

The ath9k TSF handling routines need to be aware of the channel context that
is being modified. With this change the TSF related values that are stored
in each channel context will be correctly tracked and the harware will only
be updated if the modified context is currently the active one.

Without this change the TSF modifications done using these routines would
for example be lost during a hardware reset as done by ath_complete_reset.

Signed-off-by: Benjamin Berg <[email protected]>
---
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


2016-07-04 12:38:04

by Benjamin Berg

[permalink] [raw]
Subject: [PATCH v2 4/6] ath9k: Expose tsf_adjustment in mac80211 tsf getters and setters.

From: Benjamin Berg <[email protected]>

The ath9k driver modifies the TSF for VIFs for the purpose of sending
beacons in a staggered fashion. This patch exposes this VIF specific
adjustment of the TSF value to mac80211. Without the change the TSF
routines handle the hardware TSF value instead of the actual TSF value as
seen on the air.

Signed-off-by: Benjamin Berg <[email protected]>
---
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


2016-07-04 12:38:05

by Benjamin Berg

[permalink] [raw]
Subject: [PATCH v2 3/6] ath9k: Use tsf offset helper in ath9k_hw_reset

From: Benjamin Berg <[email protected]>

These changes make ath9k_hw_reset more consistent with other places that
handle the TSF value by using the same helper routine.

A slight improvement is to not assume that a fixed time of 1.5ms has
passed for the initval writes when compared to the first write attempt.
Instead the TSF value is re-calculated which will yield a higher accuracy
of the restored TSF timer.

Signed-off-by: Benjamin Berg <[email protected]>
---
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


2016-07-04 12:38:05

by Benjamin Berg

[permalink] [raw]
Subject: [PATCH v2 5/6] ath9k: Remove some #defined constants to decrease verbosity

From: Benjamin Berg <[email protected]>

The removed ATH9K_SLOT_TIME_X constants simply map the value in microseconds
to the same integer. These constants were not used consistently, so fix the
inconsistency issue by replacing all occurances with the integer equivalent.

Signed-off-by: Benjamin Berg <[email protected]>
---
drivers/net/wireless/ath/ath9k/beacon.c | 2 +-
drivers/net/wireless/ath/ath9k/dynack.c | 4 ++--
drivers/net/wireless/ath/ath9k/htc_drv_beacon.c | 2 +-
drivers/net/wireless/ath/ath9k/htc_drv_init.c | 2 +-
drivers/net/wireless/ath/ath9k/hw.c | 2 +-
drivers/net/wireless/ath/ath9k/init.c | 2 +-
drivers/net/wireless/ath/ath9k/mac.h | 4 ----
drivers/net/wireless/ath/ath9k/main.c | 7 ++++---
8 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 800c96b..d8b4971 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -50,7 +50,7 @@ static void ath9k_beaconq_config(struct ath_softc *sc)
txq = sc->tx.txq_map[IEEE80211_AC_BE];
ath9k_hw_get_txq_props(ah, txq->axq_qnum, &qi_be);
qi.tqi_aifs = qi_be.tqi_aifs;
- if (ah->slottime == ATH9K_SLOT_TIME_20)
+ if (ah->slottime == 20)
qi.tqi_cwmin = 2*qi_be.tqi_cwmin;
else
qi.tqi_cwmin = 4*qi_be.tqi_cwmin;
diff --git a/drivers/net/wireless/ath/ath9k/dynack.c b/drivers/net/wireless/ath/ath9k/dynack.c
index d2ff0fc..7334c9b0 100644
--- a/drivers/net/wireless/ath/ath9k/dynack.c
+++ b/drivers/net/wireless/ath/ath9k/dynack.c
@@ -280,7 +280,7 @@ EXPORT_SYMBOL(ath_dynack_sample_ack_ts);
void ath_dynack_node_init(struct ath_hw *ah, struct ath_node *an)
{
/* ackto = slottime + sifs + air delay */
- u32 ackto = ATH9K_SLOT_TIME_9 + 16 + 64;
+ u32 ackto = 9 + 16 + 64;
struct ath_dynack *da = &ah->dynack;

an->ackto = ackto;
@@ -315,7 +315,7 @@ EXPORT_SYMBOL(ath_dynack_node_deinit);
void ath_dynack_reset(struct ath_hw *ah)
{
/* ackto = slottime + sifs + air delay */
- u32 ackto = ATH9K_SLOT_TIME_9 + 16 + 64;
+ u32 ackto = 9 + 16 + 64;
struct ath_dynack *da = &ah->dynack;

da->lto = jiffies;
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c b/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c
index e6bcb4c..2c0e4d2 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_beacon.c
@@ -45,7 +45,7 @@ void ath9k_htc_beaconq_config(struct ath9k_htc_priv *priv)
* Long slot time : 2x cwmin
* Short slot time : 4x cwmin
*/
- if (ah->slottime == ATH9K_SLOT_TIME_20)
+ if (ah->slottime == 20)
qi.tqi_cwmin = 2*qi_be.tqi_cwmin;
else
qi.tqi_cwmin = 4*qi_be.tqi_cwmin;
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_init.c b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
index c148c6c..b65c1b6 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_init.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
@@ -678,7 +678,7 @@ static int ath9k_init_priv(struct ath9k_htc_priv *priv,

for (i = 0; i < ATH9K_HTC_MAX_BCN_VIF; i++)
priv->beacon.bslot[i] = NULL;
- priv->beacon.slottime = ATH9K_SLOT_TIME_9;
+ priv->beacon.slottime = 9;

ath9k_cmn_init_channels_rates(common);
ath9k_cmn_init_crypto(ah);
diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index 1c27e2d..f091599 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -454,7 +454,7 @@ static void ath9k_hw_init_defaults(struct ath_hw *ah)
if (AR_SREV_9100(ah))
ah->sta_id1_defaults |= AR_STA_ID1_AR9100_BA_FIX;

- ah->slottime = ATH9K_SLOT_TIME_9;
+ ah->slottime = 9;
ah->globaltxtimeout = (u32) -1;
ah->power_mode = ATH9K_PM_UNDEFINED;
ah->htc_reset_init = true;
diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index 2ee8624..89654d5 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -372,7 +372,7 @@ static void ath9k_init_misc(struct ath_softc *sc)

common->last_rssi = ATH_RSSI_DUMMY_MARKER;
memcpy(common->bssidmask, ath_bcast_mac, ETH_ALEN);
- sc->beacon.slottime = ATH9K_SLOT_TIME_9;
+ sc->beacon.slottime = 9;

for (i = 0; i < ARRAY_SIZE(sc->beacon.bslot); i++)
sc->beacon.bslot[i] = NULL;
diff --git a/drivers/net/wireless/ath/ath9k/mac.h b/drivers/net/wireless/ath/ath9k/mac.h
index 7fbf7f9..3bab014 100644
--- a/drivers/net/wireless/ath/ath9k/mac.h
+++ b/drivers/net/wireless/ath/ath9k/mac.h
@@ -65,10 +65,6 @@
#define INIT_SSH_RETRY 32
#define INIT_SLG_RETRY 32

-#define ATH9K_SLOT_TIME_6 6
-#define ATH9K_SLOT_TIME_9 9
-#define ATH9K_SLOT_TIME_20 20
-
#define ATH9K_TXERR_XRETRY 0x01
#define ATH9K_TXERR_FILT 0x02
#define ATH9K_TXERR_FIFO 0x04
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index f2ebc85..820df45 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -926,7 +926,7 @@ static void ath9k_vif_iter(struct ath9k_vif_iter_data *iter_data,
}

if (!vif->bss_conf.use_short_slot)
- iter_data->slottime = ATH9K_SLOT_TIME_20;
+ iter_data->slottime = 20;

switch (vif->type) {
case NL80211_IFTYPE_AP:
@@ -999,7 +999,7 @@ void ath9k_calculate_iter_data(struct ath_softc *sc,
*/
memset(iter_data, 0, sizeof(*iter_data));
eth_broadcast_addr(iter_data->mask);
- iter_data->slottime = ATH9K_SLOT_TIME_9;
+ iter_data->slottime = 9;

list_for_each_entry(avp, &ctx->vifs, list)
ath9k_vif_iter(iter_data, avp->vif->addr, avp->vif);
@@ -1061,7 +1061,7 @@ static void ath9k_set_offchannel_state(struct ath_softc *sc)
ah->opmode = vif->type;
ah->imask &= ~ATH9K_INT_SWBA;
ah->imask &= ~ATH9K_INT_TSFOOR;
- ah->slottime = ATH9K_SLOT_TIME_9;
+ ah->slottime = 9;

ath_hw_setbssidmask(common);
ath9k_hw_setopmode(ah);
@@ -1788,6 +1788,7 @@ static void ath9k_bss_info_changed(struct ieee80211_hw *hw,
slottime = 9;
else
slottime = 20;
+
if (vif->type == NL80211_IFTYPE_AP) {
/*
* Defer update, so that connected stations can adjust
--
2.8.1


2016-07-04 12:38:05

by Benjamin Berg

[permalink] [raw]
Subject: [PATCH v2 6/6] ath9k: Fix beacon configuration for addition/removal of interfaces

From: Benjamin Berg <[email protected]>

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. When this happens
the driver never sends out the beacon as it only tries to send a beacon
from slot 0.

Appart from that the tracking of required changes to the beacon config is
relatively complicated and prone to errors.

The approach taken here is to solve reconfiguration issues is to
reconfigure the beacons when any interface changes. This means that
the complexity of deciding whether an interface change may modify the
beacon configuration is gone. It also means that the beacon config will
be reliably updated when an interface is removed.

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 <[email protected]>
---
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 d8b4971..e36f947 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 820df45..7594650 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


2016-07-08 14:04:21

by Kalle Valo

[permalink] [raw]
Subject: Re: [v2, 1/6] ath9k: Correct TSF adjustment to align the beacon time correctly

Benjamin Berg <[email protected]> wrote:
> From: Benjamin Berg <[email protected]>
>
> Beacons were not send out at (timestamp % beacon_time == 0) for interfaces
> other than the primary one. To send out beacons with the correct timestamp
> according to 10.1.3.2 of the 802.11 standard the tsf_adjustment has to be
> set to the negative time difference instead of positive. This way the
> later beacons get corrected to have a lower (and similar) timestamp with
> regard to the beacon from slot 0.
>
> I am not aware about any issues that have been caused by this.
>
> Signed-off-by: Benjamin Berg <[email protected]>

Thanks, 6 patches applied to ath-next branch of ath.git:

fa5106e1d793 ath9k: Correct TSF adjustment to align the beacon time correctly
9580cb889f35 ath9k: Handle channel context in get_/set_/reset_tsf
bec9a94bc4e2 ath9k: Use tsf offset helper in ath9k_hw_reset
7fde51227aed ath9k: Expose tsf_adjustment in mac80211 tsf getters and setters.
11b0ac2e0c1c ath9k: Remove some #defined constants to decrease verbosity
cfda2d8e2314 ath9k: Fix beacon configuration for addition/removal of interfaces

--
Sent by pwcli
https://patchwork.kernel.org/patch/9212535/