From dcfcbd590d91e8385eb554aaed419bdebaf4c72a Mon Sep 17 00:00:00 2001 From: Rajkumar Manoharan Date: Thu, 23 Jun 2011 13:39:13 +0530 Subject: ath9k_hw: Fix false tx hung detection in AR9003 chips The edma based (AR9003 family) chips update tx status descriptors in a common ring buffer for all transmitted frames. Whenever tx interrupt is raised, the descriptors are processed and tx status index is moved. The complete tx stauts ring are updated with beacons tx status when there are no data frames to be sent for a period of time. In this state, transmitting data frames causes the driver to wait for the tx status on an incorrect tx status index though the status was updated by hw properly. The driver detects this condition as a h/w hang and does unnecessary chip resets. This issue was orginally reported in adhoc mode while sending frames after an idle time. Signed-off-by: Rajkumar Manoharan Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/beacon.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/net/wireless/ath/ath9k/beacon.c') diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c index 0174cdb65a8..0b6e3b65bb0 100644 --- a/drivers/net/wireless/ath/ath9k/beacon.c +++ b/drivers/net/wireless/ath/ath9k/beacon.c @@ -360,6 +360,7 @@ void ath_beacon_tasklet(unsigned long data) struct ath_common *common = ath9k_hw_common(ah); struct ath_buf *bf = NULL; struct ieee80211_vif *vif; + struct ath_tx_status ts; int slot; u32 bfaddr, bc = 0; @@ -464,6 +465,11 @@ void ath_beacon_tasklet(unsigned long data) ath9k_hw_txstart(ah, sc->beacon.beaconq); sc->beacon.ast_be_xmit += bc; /* XXX per-vif? */ + if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) { + spin_lock_bh(&sc->sc_pcu_lock); + ath9k_hw_txprocdesc(ah, bf->bf_desc, (void *)&ts); + spin_unlock_bh(&sc->sc_pcu_lock); + } } } -- cgit v1.2.3-70-g09d2 From f6b4e4d476b890e1ddebbed8ec4924f9c2750a31 Mon Sep 17 00:00:00 2001 From: Rajkumar Manoharan Date: Fri, 24 Jun 2011 17:38:13 +0530 Subject: ath9k: Fix locking issue during tx completion The received tx status of aggregated frame without BlockAck may cause deaf state in AR5416 cards. So the driver does a reset to recover. When this happens, we release the pcu_lock before doing a reset as ath_rest acquires pcu_lock. This is ugly and also not atomic. Fixing this addresses the TX DMA failure also. ath_tx_complete_aggr can be called from different paths which takes different variants of spin_lock. This patch also addresses the following warning. WARNING: at kernel/timer.c:1011 del_timer_sync+0x4e/0x50() Call Trace: [] warn_slowpath_common+0x7a/0xb0 [] warn_slowpath_null+0x15/0x20 [] del_timer_sync+0x4e/0x50 [] ath_reset+0x3e/0x210 [ath9k] [] ? _raw_spin_unlock_bh+0x1f/0x30 [] ath_tx_complete_aggr.isra.26+0x54a/0xa40 [ath9k] Signed-off-by: Rajkumar Manoharan Signed-off-by: John W. Linville --- drivers/net/wireless/ath/ath9k/beacon.c | 2 ++ drivers/net/wireless/ath/ath9k/main.c | 13 +++++++++---- drivers/net/wireless/ath/ath9k/xmit.c | 7 +++---- 3 files changed, 14 insertions(+), 8 deletions(-) (limited to 'drivers/net/wireless/ath/ath9k/beacon.c') diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c index 0b6e3b65bb0..e19a230dfff 100644 --- a/drivers/net/wireless/ath/ath9k/beacon.c +++ b/drivers/net/wireless/ath/ath9k/beacon.c @@ -385,7 +385,9 @@ void ath_beacon_tasklet(unsigned long data) ath_dbg(common, ATH_DBG_BSTUCK, "beacon is officially stuck\n"); sc->sc_flags |= SC_OP_TSF_RESET; + spin_lock(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock(&sc->sc_pcu_lock); } return; diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index 5ae303b11e6..9098aaad97a 100644 --- a/drivers/net/wireless/ath/ath9k/main.c +++ b/drivers/net/wireless/ath/ath9k/main.c @@ -617,8 +617,11 @@ void ath_hw_check(struct work_struct *work) ath_dbg(common, ATH_DBG_RESET, "Possible baseband hang, " "busy=%d (try %d)\n", busy, sc->hw_busy_count + 1); if (busy >= 99) { - if (++sc->hw_busy_count >= 3) + if (++sc->hw_busy_count >= 3) { + spin_lock_bh(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock_bh(&sc->sc_pcu_lock); + } } else if (busy >= 0) sc->hw_busy_count = 0; @@ -637,7 +640,9 @@ static void ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum) /* Rx is hung for more than 500ms. Reset it */ ath_dbg(common, ATH_DBG_RESET, "Possible RX hang, resetting"); + spin_lock_bh(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock_bh(&sc->sc_pcu_lock); count = 0; } } else @@ -674,7 +679,9 @@ void ath9k_tasklet(unsigned long data) if ((status & ATH9K_INT_FATAL) || (status & ATH9K_INT_BB_WATCHDOG)) { + spin_lock(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock(&sc->sc_pcu_lock); return; } @@ -980,7 +987,6 @@ int ath_reset(struct ath_softc *sc, bool retry_tx) del_timer_sync(&common->ani.timer); ath9k_ps_wakeup(sc); - spin_lock_bh(&sc->sc_pcu_lock); ieee80211_stop_queues(hw); @@ -1023,7 +1029,6 @@ int ath_reset(struct ath_softc *sc, bool retry_tx) } ieee80211_wake_queues(hw); - spin_unlock_bh(&sc->sc_pcu_lock); /* Start ANI */ if (!common->disable_ani) @@ -2326,9 +2331,9 @@ static void ath9k_flush(struct ieee80211_hw *hw, bool drop) ath9k_ps_wakeup(sc); spin_lock_bh(&sc->sc_pcu_lock); drain_txq = ath_drain_all_txq(sc, false); - spin_unlock_bh(&sc->sc_pcu_lock); if (!drain_txq) ath_reset(sc, false); + spin_unlock_bh(&sc->sc_pcu_lock); ath9k_ps_restore(sc); ieee80211_wake_queues(hw); diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index ec012b4317a..a1fed6c8ff9 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -565,11 +565,8 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq, rcu_read_unlock(); - if (needreset) { - spin_unlock_bh(&sc->sc_pcu_lock); + if (needreset) ath_reset(sc, false); - spin_lock_bh(&sc->sc_pcu_lock); - } } static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf, @@ -2169,7 +2166,9 @@ static void ath_tx_complete_poll_work(struct work_struct *work) if (needreset) { ath_dbg(ath9k_hw_common(sc->sc_ah), ATH_DBG_RESET, "tx hung, resetting the chip\n"); + spin_lock_bh(&sc->sc_pcu_lock); ath_reset(sc, true); + spin_unlock_bh(&sc->sc_pcu_lock); } ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work, -- cgit v1.2.3-70-g09d2