ath9k_hw: improve ANI processing and rx desensitizing parameters

This patch improves ANI operations by switching among the immunity
levels based on PHY errors and beacon rssi which will adjust receiver
desensitizing parameters. The changes are

* Configure the Weak Signal Detection based on current immunity value.
* At highest OFDM immunity level poor performance was observed with
  strong interference. By tuning the FIR step and spur immunity levels
  and not changing any weak signal detection thresholds at any level
  helped to improve the performance.
* ANI took long time to recover back to lower immunity levels on heavy
  data load. As the listen time got reset to zero before reaching to
  the 5x of aniperiod, the immunity level is not lowering back even
  without any interference. This patch fix that.

Cc: Paul Stewart <pstew@google.com>
Cc: Susinder Gulasekaran <susinder@qca.qualcomm.com>
Signed-off-by: Suresh Chandrasekaran <csuresh@qca.qualcomm.com>
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 23 insertions, 26 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ani.c b/drivers/net/wireless/ath/ath9k/ani.c
index 7e0ea4e98334..47a9fb4a116a 100644
--- a/drivers/net/wireless/ath/ath9k/ani.c
+++ b/drivers/net/wireless/ath/ath9k/ani.c
@@ -46,8 +46,8 @@ static const struct ani_ofdm_level_entry ofdm_level_table[] = {
 	{  5,  4,  1  }, /* lvl 5 */
 	{  6,  5,  1  }, /* lvl 6 */
 	{  7,  6,  1  }, /* lvl 7 */
-	{  7,  7,  1  }, /* lvl 8 */
-	{  7,  8,  0  }  /* lvl 9 */
+	{  7,  6,  0  }, /* lvl 8 */
+	{  7,  7,  0  }  /* lvl 9 */
 };
 #define ATH9K_ANI_OFDM_NUM_LEVEL \
 	ARRAY_SIZE(ofdm_level_table)
@@ -91,8 +91,8 @@ static const struct ani_cck_level_entry cck_level_table[] = {
 	{  4,  0  }, /* lvl 4 */
 	{  5,  0  }, /* lvl 5 */
 	{  6,  0  }, /* lvl 6 */
-	{  7,  0  }, /* lvl 7 (only for high rssi) */
-	{  8,  0  }  /* lvl 8 (only for high rssi) */
+	{  6,  0  }, /* lvl 7 (only for high rssi) */
+	{  7,  0  }  /* lvl 8 (only for high rssi) */
 };
 
 #define ATH9K_ANI_CCK_NUM_LEVEL \
@@ -290,16 +290,9 @@ static void ath9k_hw_set_ofdm_nil(struct ath_hw *ah, u8 immunityLevel)
 				     ATH9K_ANI_FIRSTEP_LEVEL,
 				     entry_ofdm->fir_step_level);
 
-	if ((ah->opmode != NL80211_IFTYPE_STATION &&
-	     ah->opmode != NL80211_IFTYPE_ADHOC) ||
-	    aniState->noiseFloor <= aniState->rssiThrHigh) {
-		if (aniState->ofdmWeakSigDetectOff)
-			/* force on ofdm weak sig detect */
-			ath9k_hw_ani_control(ah,
-				ATH9K_ANI_OFDM_WEAK_SIGNAL_DETECTION,
-					     true);
-		else if (aniState->ofdmWeakSigDetectOff ==
-			 entry_ofdm->ofdm_weak_signal_on)
+	if ((aniState->noiseFloor >= aniState->rssiThrHigh) &&
+	    (!aniState->ofdmWeakSigDetectOff !=
+	     entry_ofdm->ofdm_weak_signal_on)) {
 			ath9k_hw_ani_control(ah,
 				ATH9K_ANI_OFDM_WEAK_SIGNAL_DETECTION,
 				entry_ofdm->ofdm_weak_signal_on);
@@ -717,26 +710,30 @@ void ath9k_hw_ani_monitor(struct ath_hw *ah, struct ath9k_channel *chan)
 		ofdmPhyErrRate, aniState->cckNoiseImmunityLevel,
 		cckPhyErrRate, aniState->ofdmsTurn);
 
-	if (aniState->listenTime > 5 * ah->aniperiod) {
-		if (ofdmPhyErrRate <= ah->config.ofdm_trig_low &&
-		    cckPhyErrRate <= ah->config.cck_trig_low) {
+	if (aniState->listenTime > ah->aniperiod) {
+		if (cckPhyErrRate < ah->config.cck_trig_low &&
+		    ((ofdmPhyErrRate < ah->config.ofdm_trig_low &&
+		      aniState->ofdmNoiseImmunityLevel <
+		      ATH9K_ANI_OFDM_DEF_LEVEL) ||
+		     (ofdmPhyErrRate < ATH9K_ANI_OFDM_TRIG_LOW_ABOVE_INI &&
+		      aniState->ofdmNoiseImmunityLevel >=
+		      ATH9K_ANI_OFDM_DEF_LEVEL))) {
 			ath9k_hw_ani_lower_immunity(ah);
 			aniState->ofdmsTurn = !aniState->ofdmsTurn;
-		}
-		ath9k_ani_restart(ah);
-	} else if (aniState->listenTime > ah->aniperiod) {
-		/* check to see if need to raise immunity */
-		if (ofdmPhyErrRate > ah->config.ofdm_trig_high &&
-		    (cckPhyErrRate <= ah->config.cck_trig_high ||
-		     aniState->ofdmsTurn)) {
+		} else if ((ofdmPhyErrRate > ah->config.ofdm_trig_high &&
+			    aniState->ofdmNoiseImmunityLevel >=
+			    ATH9K_ANI_OFDM_DEF_LEVEL) ||
+			   (ofdmPhyErrRate >
+			    ATH9K_ANI_OFDM_TRIG_HIGH_BELOW_INI &&
+			    aniState->ofdmNoiseImmunityLevel <
+			    ATH9K_ANI_OFDM_DEF_LEVEL)) {
 			ath9k_hw_ani_ofdm_err_trigger(ah);
-			ath9k_ani_restart(ah);
 			aniState->ofdmsTurn = false;
 		} else if (cckPhyErrRate > ah->config.cck_trig_high) {
 			ath9k_hw_ani_cck_err_trigger(ah);
-			ath9k_ani_restart(ah);
 			aniState->ofdmsTurn = true;
 		}
+		ath9k_ani_restart(ah);
 	}
 }
 EXPORT_SYMBOL(ath9k_hw_ani_monitor);