This is a note to let you know that I've just added the patch titled ath9k: Fix interrupt handling for the AR9002 family to the 3.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ath9k-fix-interrupt-handling-for-the-ar9002-family.patch and it can be found in the queue-3.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 73f0b56a1ff64e7fb6c3a62088804bab93bcedc2 Mon Sep 17 00:00:00 2001 From: Sujith Manoharan <c_manoha@xxxxxxxxxxxxxxxx> Date: Mon, 16 Dec 2013 07:04:59 +0530 Subject: ath9k: Fix interrupt handling for the AR9002 family From: Sujith Manoharan <c_manoha@xxxxxxxxxxxxxxxx> commit 73f0b56a1ff64e7fb6c3a62088804bab93bcedc2 upstream. This patch adds a driver workaround for a HW issue. A race condition in the HW results in missing interrupts, which can be avoided by a read/write with the ISR register. All chips in the AR9002 series are affected by this bug - AR9003 and above do not have this problem. Cc: Felix Fietkau <nbd@xxxxxxxxxxx> Signed-off-by: Sujith Manoharan <c_manoha@xxxxxxxxxxxxxxxx> Signed-off-by: John W. Linville <linville@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/ath/ath9k/ar9002_mac.c | 52 +++++++++++++++++++++++----- 1 file changed, 43 insertions(+), 9 deletions(-) --- a/drivers/net/wireless/ath/ath9k/ar9002_mac.c +++ b/drivers/net/wireless/ath/ath9k/ar9002_mac.c @@ -76,9 +76,16 @@ static bool ar9002_hw_get_isr(struct ath mask2 |= ATH9K_INT_CST; if (isr2 & AR_ISR_S2_TSFOOR) mask2 |= ATH9K_INT_TSFOOR; + + if (!(pCap->hw_caps & ATH9K_HW_CAP_RAC_SUPPORTED)) { + REG_WRITE(ah, AR_ISR_S2, isr2); + isr &= ~AR_ISR_BCNMISC; + } } - isr = REG_READ(ah, AR_ISR_RAC); + if (pCap->hw_caps & ATH9K_HW_CAP_RAC_SUPPORTED) + isr = REG_READ(ah, AR_ISR_RAC); + if (isr == 0xffffffff) { *masked = 0; return false; @@ -97,11 +104,23 @@ static bool ar9002_hw_get_isr(struct ath *masked |= ATH9K_INT_TX; - s0_s = REG_READ(ah, AR_ISR_S0_S); + if (pCap->hw_caps & ATH9K_HW_CAP_RAC_SUPPORTED) { + s0_s = REG_READ(ah, AR_ISR_S0_S); + s1_s = REG_READ(ah, AR_ISR_S1_S); + } else { + s0_s = REG_READ(ah, AR_ISR_S0); + REG_WRITE(ah, AR_ISR_S0, s0_s); + s1_s = REG_READ(ah, AR_ISR_S1); + REG_WRITE(ah, AR_ISR_S1, s1_s); + + isr &= ~(AR_ISR_TXOK | + AR_ISR_TXDESC | + AR_ISR_TXERR | + AR_ISR_TXEOL); + } + ah->intr_txqs |= MS(s0_s, AR_ISR_S0_QCU_TXOK); ah->intr_txqs |= MS(s0_s, AR_ISR_S0_QCU_TXDESC); - - s1_s = REG_READ(ah, AR_ISR_S1_S); ah->intr_txqs |= MS(s1_s, AR_ISR_S1_QCU_TXERR); ah->intr_txqs |= MS(s1_s, AR_ISR_S1_QCU_TXEOL); } @@ -114,13 +133,15 @@ static bool ar9002_hw_get_isr(struct ath *masked |= mask2; } - if (AR_SREV_9100(ah)) - return true; - - if (isr & AR_ISR_GENTMR) { + if (!AR_SREV_9100(ah) && (isr & AR_ISR_GENTMR)) { u32 s5_s; - s5_s = REG_READ(ah, AR_ISR_S5_S); + if (pCap->hw_caps & ATH9K_HW_CAP_RAC_SUPPORTED) { + s5_s = REG_READ(ah, AR_ISR_S5_S); + } else { + s5_s = REG_READ(ah, AR_ISR_S5); + } + ah->intr_gen_timer_trigger = MS(s5_s, AR_ISR_S5_GENTIMER_TRIG); @@ -133,8 +154,21 @@ static bool ar9002_hw_get_isr(struct ath if ((s5_s & AR_ISR_S5_TIM_TIMER) && !(pCap->hw_caps & ATH9K_HW_CAP_AUTOSLEEP)) *masked |= ATH9K_INT_TIM_TIMER; + + if (!(pCap->hw_caps & ATH9K_HW_CAP_RAC_SUPPORTED)) { + REG_WRITE(ah, AR_ISR_S5, s5_s); + isr &= ~AR_ISR_GENTMR; + } + } + + if (!(pCap->hw_caps & ATH9K_HW_CAP_RAC_SUPPORTED)) { + REG_WRITE(ah, AR_ISR, isr); + REG_READ(ah, AR_ISR); } + if (AR_SREV_9100(ah)) + return true; + if (sync_cause) { fatal_int = (sync_cause & Patches currently in stable-queue which might be from c_manoha@xxxxxxxxxxxxxxxx are queue-3.4/ath9k-fix-interrupt-handling-for-the-ar9002-family.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html