3.10-stable review patch. If anyone has any objections, please let me know.
------------------
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) {
ath9k_debug_sync_cause(common, sync_cause);
fatal_int =
--
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