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[3.8.y.z,extended,stable] Patch "ath9k: Fix interrupt handling for the AR9002 family" has been added to staging queue

Message ID 1389641056-20092-1-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa Jan. 13, 2014, 7:24 p.m. UTC
This is a note to let you know that I have just added a patch titled

    ath9k: Fix interrupt handling for the AR9002 family

to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue

This patch is scheduled to be released in version 3.8.13.16.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.8.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

From ae60a6740bf9155d23e9aa06f3095d27f61323a0 Mon Sep 17 00:00:00 2001
From: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Date: Mon, 16 Dec 2013 07:04:59 +0530
Subject: ath9k: Fix interrupt handling for the AR9002 family

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@openwrt.org>
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 drivers/net/wireless/ath/ath9k/ar9002_mac.c | 52 ++++++++++++++++++++++++-----
 1 file changed, 43 insertions(+), 9 deletions(-)

--
1.8.3.2
diff mbox

Patch

diff --git a/drivers/net/wireless/ath/ath9k/ar9002_mac.c b/drivers/net/wireless/ath/ath9k/ar9002_mac.c
index 8d78253..a366d6b 100644
--- 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_hw *ah, enum ath9k_int *masked)
 				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_hw *ah, enum ath9k_int *masked)

 			*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_hw *ah, enum ath9k_int *masked)
 		*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_hw *ah, enum ath9k_int *masked)
 		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 =