ath9k: use external reset on AR91xx and QCA955x to improve stability

Signed-off-by: Felix Fietkau <nbd@nbd.name>

1 files changed, 125 insertions, 0 deletions

diff --git a/package/kernel/mac80211/patches/322-ath9k_hw-issue-external-reset-for-QCA9550.patch b/package/kernel/mac80211/patches/322-ath9k_hw-issue-external-reset-for-QCA9550.patch
new file mode 100644
index 0000000000..5d4e849b7f
--- /dev/null
+++ b/package/kernel/mac80211/patches/322-ath9k_hw-issue-external-reset-for-QCA9550.patch
@@ -0,0 +1,125 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sat, 9 Jul 2016 15:26:44 +0200
+Subject: [PATCH] ath9k_hw: issue external reset for QCA9550
+
+The RTC interface on the SoC needs to be reset along with the rest of
+the WMAC.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/drivers/net/wireless/ath/ath9k/hw.c
++++ b/drivers/net/wireless/ath/ath9k/hw.c
+@@ -1275,39 +1275,56 @@ void ath9k_hw_get_delta_slope_vals(struc
+ 	*coef_exponent = coef_exp - 16;
+ }
+ 
+-/* AR9330 WAR:
+- * call external reset function to reset WMAC if:
+- * - doing a cold reset
+- * - we have pending frames in the TX queues.
+- */
+-static bool ath9k_hw_ar9330_reset_war(struct ath_hw *ah, int type)
++static bool ath9k_hw_need_external_reset(struct ath_hw *ah, int type)
+ {
+-	int i, npend = 0;
++	int i;
+ 
+-	for (i = 0; i < AR_NUM_QCU; i++) {
+-		npend = ath9k_hw_numtxpending(ah, i);
+-		if (npend)
+-			break;
++	if (type == ATH9K_RESET_COLD)
++		return true;
++
++	if (AR_SREV_9550(ah))
++		return true;
++
++	/* AR9330 WAR:
++	 * call external reset function to reset WMAC if:
++	 * - doing a cold reset
++	 * - we have pending frames in the TX queues.
++	 */
++	if (AR_SREV_9330(ah)) {
++		for (i = 0; i < AR_NUM_QCU; i++) {
++			if (ath9k_hw_numtxpending(ah, i))
++				return true;
++		}
+ 	}
+ 
+-	if (ah->external_reset &&
+-	    (npend || type == ATH9K_RESET_COLD)) {
+-		int reset_err = 0;
++	return false;
++}
+ 
+-		ath_dbg(ath9k_hw_common(ah), RESET,
+-			"reset MAC via external reset\n");
++static bool ath9k_hw_external_reset(struct ath_hw *ah, int type)
++{
++	int err;
+ 
+-		reset_err = ah->external_reset();
+-		if (reset_err) {
+-			ath_err(ath9k_hw_common(ah),
+-				"External reset failed, err=%d\n",
+-				reset_err);
+-			return false;
+-		}
++	if (!ah->external_reset || !ath9k_hw_need_external_reset(ah, type))
++		return true;
+ 
+-		REG_WRITE(ah, AR_RTC_RESET, 1);
++	ath_dbg(ath9k_hw_common(ah), RESET,
++		"reset MAC via external reset\n");
++
++	err = ah->external_reset();
++	if (err) {
++		ath_err(ath9k_hw_common(ah),
++			"External reset failed, err=%d\n", err);
++		return false;
++	}
++
++	if (AR_SREV_9550(ah)) {
++		REG_WRITE(ah, AR_RTC_RESET, 0);
++		udelay(10);
+ 	}
+ 
++	REG_WRITE(ah, AR_RTC_RESET, 1);
++	udelay(10);
++
+ 	return true;
+ }
+ 
+@@ -1360,24 +1377,23 @@ static bool ath9k_hw_set_reset(struct at
+ 			rst_flags |= AR_RTC_RC_MAC_COLD;
+ 	}
+ 
+-	if (AR_SREV_9330(ah)) {
+-		if (!ath9k_hw_ar9330_reset_war(ah, type))
+-			return false;
+-	}
+-
+ 	if (ath9k_hw_mci_is_enabled(ah))
+ 		ar9003_mci_check_gpm_offset(ah);
+ 
+ 	/* DMA HALT added to resolve ar9300 and ar9580 bus error during
+-	 * RTC_RC reg read
++	 * RTC_RC reg read. Also needed for AR9550 external reset
+ 	 */
+-	if (AR_SREV_9300(ah) || AR_SREV_9580(ah)) {
++	if (AR_SREV_9300(ah) || AR_SREV_9580(ah) || AR_SREV_9550(ah)) {
+ 		REG_SET_BIT(ah, AR_CFG, AR_CFG_HALT_REQ);
+ 		ath9k_hw_wait(ah, AR_CFG, AR_CFG_HALT_ACK, AR_CFG_HALT_ACK,
+ 			      20 * AH_WAIT_TIMEOUT);
+-		REG_CLR_BIT(ah, AR_CFG, AR_CFG_HALT_REQ);
+ 	}
+ 
++	ath9k_hw_external_reset(ah, type);
++
++	if (AR_SREV_9300(ah) || AR_SREV_9580(ah))
++		REG_CLR_BIT(ah, AR_CFG, AR_CFG_HALT_REQ);
++
+ 	REG_WRITE(ah, AR_RTC_RC, rst_flags);
+ 
+ 	REGWRITE_BUFFER_FLUSH(ah);