ath9k: improve noise immunity behavior for older chipsets (ar92xx and earlier), should improve stability

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

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39767 3c298f89-4303-0410-b956-a3cf2f4a3e73
master
Felix Fietkau 2014-02-28 18:08:23 +00:00
parent e6fbcf4df8
commit 44de5c8d01
2 changed files with 117 additions and 1 deletions

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@ -1,3 +1,41 @@
commit 1abdeca3c6fb9cf1f84f85e78ed8d1c33bd69db0
Author: Felix Fietkau <nbd@openwrt.org>
Date: Fri Feb 28 18:52:56 2014 +0100
ath9k_hw: tweak noise immunity thresholds for older chipsets
Older chipsets are more sensitive to high PHY error counts, and the
current noise immunity thresholds were based on tests run at QCA with
newer chipsets.
This patch brings back the values from the old ANI implementation for
old chipsets, and it also disables weak signal detection on an earlier
noise immunity level, to improve overall radio stability on affected
devices.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
commit 431e506da5953adc3b65af25f4b90873d528c115
Author: Felix Fietkau <nbd@openwrt.org>
Date: Fri Feb 28 18:44:13 2014 +0100
ath9k_hw: toggle weak signal detection in AP mode on older chipsets
The commit 80b4205b "ath9k: Fix OFDM weak signal detection for AP mode"
prevented weak signal detection changes from taking effect in AP mode on
all chipsets, claiming it is "not allowed".
The main reason for not disabling weak signal detection in AP mode is
that typically beacon RSSI is used to track whether it is needed to
boost range, and this is unavailable in AP mode for obvious reasons.
The problem with not disabling weak signal detection is that older
chipsets are very sensitive to high PHY error counts. When faced with
heavy noise, this can lead to an excessive amount of "Failed to stop
TX DMA" errors in the field.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
commit 98d1a6c5b14688ed030e81b889f607be308e0df9
Author: Felix Fietkau <nbd@openwrt.org>
Date: Mon Feb 24 22:20:32 2014 +0100
@ -3591,3 +3629,81 @@ Date: Thu Jan 23 20:06:34 2014 +0100
}
static void ath9k_rx_skb_postprocess(struct ath_common *common,
--- a/drivers/net/wireless/ath/ath9k/ani.c
+++ b/drivers/net/wireless/ath/ath9k/ani.c
@@ -176,16 +176,26 @@ static void ath9k_hw_set_ofdm_nil(struct
if (ah->opmode == NL80211_IFTYPE_STATION &&
BEACON_RSSI(ah) <= ATH9K_ANI_RSSI_THR_HIGH)
weak_sig = true;
-
/*
- * OFDM Weak signal detection is always enabled for AP mode.
+ * Newer chipsets are better at dealing with high PHY error counts -
+ * keep weak signal detection enabled when no RSSI threshold is
+ * available to determine if it is needed (mode != STA)
*/
- if (ah->opmode != NL80211_IFTYPE_AP &&
- aniState->ofdmWeakSigDetect != weak_sig) {
- ath9k_hw_ani_control(ah,
- ATH9K_ANI_OFDM_WEAK_SIGNAL_DETECTION,
- entry_ofdm->ofdm_weak_signal_on);
- }
+ else if (AR_SREV_9300_20_OR_LATER(ah) &&
+ ah->opmode != NL80211_IFTYPE_STATION)
+ weak_sig = true;
+
+ /* Older chipsets are more sensitive to high PHY error counts */
+ else if (!AR_SREV_9300_20_OR_LATER(ah) &&
+ aniState->ofdmNoiseImmunityLevel >= 8)
+ weak_sig = false;
+
+ if (aniState->ofdmWeakSigDetect != weak_sig)
+ ath9k_hw_ani_control(ah, ATH9K_ANI_OFDM_WEAK_SIGNAL_DETECTION,
+ weak_sig);
+
+ if (!AR_SREV_9300_20_OR_LATER(ah))
+ return;
if (aniState->ofdmNoiseImmunityLevel >= ATH9K_ANI_OFDM_DEF_LEVEL) {
ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH;
@@ -483,10 +493,17 @@ void ath9k_hw_ani_init(struct ath_hw *ah
ath_dbg(common, ANI, "Initialize ANI\n");
- ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH;
- ah->config.ofdm_trig_low = ATH9K_ANI_OFDM_TRIG_LOW;
- ah->config.cck_trig_high = ATH9K_ANI_CCK_TRIG_HIGH;
- ah->config.cck_trig_low = ATH9K_ANI_CCK_TRIG_LOW;
+ if (AR_SREV_9300_20_OR_LATER(ah)) {
+ ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH;
+ ah->config.ofdm_trig_low = ATH9K_ANI_OFDM_TRIG_LOW;
+ ah->config.cck_trig_high = ATH9K_ANI_CCK_TRIG_HIGH;
+ ah->config.cck_trig_low = ATH9K_ANI_CCK_TRIG_LOW;
+ } else {
+ ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH_OLD;
+ ah->config.ofdm_trig_low = ATH9K_ANI_OFDM_TRIG_LOW_OLD;
+ ah->config.cck_trig_high = ATH9K_ANI_CCK_TRIG_HIGH_OLD;
+ ah->config.cck_trig_low = ATH9K_ANI_CCK_TRIG_LOW_OLD;
+ }
ani->spurImmunityLevel = ATH9K_ANI_SPUR_IMMUNE_LVL;
ani->firstepLevel = ATH9K_ANI_FIRSTEP_LVL;
--- a/drivers/net/wireless/ath/ath9k/ani.h
+++ b/drivers/net/wireless/ath/ath9k/ani.h
@@ -22,12 +22,16 @@
/* units are errors per second */
#define ATH9K_ANI_OFDM_TRIG_HIGH 3500
#define ATH9K_ANI_OFDM_TRIG_HIGH_BELOW_INI 1000
+#define ATH9K_ANI_OFDM_TRIG_HIGH_OLD 500
#define ATH9K_ANI_OFDM_TRIG_LOW 400
#define ATH9K_ANI_OFDM_TRIG_LOW_ABOVE_INI 900
+#define ATH9K_ANI_OFDM_TRIG_LOW_OLD 200
#define ATH9K_ANI_CCK_TRIG_HIGH 600
+#define ATH9K_ANI_CCK_TRIG_HIGH_OLD 200
#define ATH9K_ANI_CCK_TRIG_LOW 300
+#define ATH9K_ANI_CCK_TRIG_LOW_OLD 100
#define ATH9K_ANI_SPUR_IMMUNE_LVL 3
#define ATH9K_ANI_FIRSTEP_LVL 2

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@ -1,6 +1,6 @@
--- a/drivers/net/wireless/ath/ath9k/ani.h
+++ b/drivers/net/wireless/ath/ath9k/ani.h
@@ -38,7 +38,7 @@
@@ -42,7 +42,7 @@
#define ATH9K_ANI_PERIOD 300
/* in ms */