1 files changed, 153 insertions, 71 deletions

diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c
index 45208690c0e..278365b8a89 100644
--- a/drivers/net/wireless/ath/ath9k/calib.c
+++ b/drivers/net/wireless/ath/ath9k/calib.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008-2009 Atheros Communications Inc.
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -16,11 +16,10 @@
 
 #include "hw.h"
 #include "hw-ops.h"
+#include <linux/export.h>
 
 /* Common calibration code */
 
-/* We can tune this as we go by monitoring really low values */
-#define ATH9K_NF_TOO_LOW	-60
 
 static int16_t ath9k_hw_get_nf_hist_mid(int16_t *nfCalBuffer)
 {
@@ -45,12 +44,59 @@ static int16_t ath9k_hw_get_nf_hist_mid(int16_t *nfCalBuffer)
 	return nfval;
 }
 
-static void ath9k_hw_update_nfcal_hist_buffer(struct ath9k_nfcal_hist *h,
+static struct ath_nf_limits *ath9k_hw_get_nf_limits(struct ath_hw *ah,
+						    struct ath9k_channel *chan)
+{
+	struct ath_nf_limits *limit;
+
+	if (!chan || IS_CHAN_2GHZ(chan))
+		limit = &ah->nf_2g;
+	else
+		limit = &ah->nf_5g;
+
+	return limit;
+}
+
+static s16 ath9k_hw_get_default_nf(struct ath_hw *ah,
+				   struct ath9k_channel *chan)
+{
+	return ath9k_hw_get_nf_limits(ah, chan)->nominal;
+}
+
+s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan,
+			   s16 nf)
+{
+	s8 noise = ATH_DEFAULT_NOISE_FLOOR;
+
+	if (nf) {
+		s8 delta = nf - ATH9K_NF_CAL_NOISE_THRESH -
+			   ath9k_hw_get_default_nf(ah, chan);
+		if (delta > 0)
+			noise += delta;
+	}
+	return noise;
+}
+EXPORT_SYMBOL(ath9k_hw_getchan_noise);
+
+static void ath9k_hw_update_nfcal_hist_buffer(struct ath_hw *ah,
+					      struct ath9k_hw_cal_data *cal,
 					      int16_t *nfarray)
 {
+	struct ath_common *common = ath9k_hw_common(ah);
+	struct ath_nf_limits *limit;
+	struct ath9k_nfcal_hist *h;
+	bool high_nf_mid = false;
+	u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
 	int i;
 
+	h = cal->nfCalHist;
+	limit = ath9k_hw_get_nf_limits(ah, ah->curchan);
+
 	for (i = 0; i < NUM_NF_READINGS; i++) {
+		if (!(chainmask & (1 << i)) ||
+		    ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(ah->curchan)))
+			continue;
+
 		h[i].nfCalBuffer[h[i].currIndex] = nfarray[i];
 
 		if (++h[i].currIndex >= ATH9K_NF_CAL_HIST_MAX)
@@ -63,7 +109,39 @@ static void ath9k_hw_update_nfcal_hist_buffer(struct ath9k_nfcal_hist *h,
 			h[i].privNF =
 				ath9k_hw_get_nf_hist_mid(h[i].nfCalBuffer);
 		}
+
+		if (!h[i].privNF)
+			continue;
+
+		if (h[i].privNF > limit->max) {
+			high_nf_mid = true;
+
+			ath_dbg(common, CALIBRATE,
+				"NFmid[%d] (%d) > MAX (%d), %s\n",
+				i, h[i].privNF, limit->max,
+				(test_bit(NFCAL_INTF, &cal->cal_flags) ?
+				 "not corrected (due to interference)" :
+				 "correcting to MAX"));
+
+			/*
+			 * Normally we limit the average noise floor by the
+			 * hardware specific maximum here. However if we have
+			 * encountered stuck beacons because of interference,
+			 * we bypass this limit here in order to better deal
+			 * with our environment.
+			 */
+			if (!test_bit(NFCAL_INTF, &cal->cal_flags))
+				h[i].privNF = limit->max;
+		}
 	}
+
+	/*
+	 * If the noise floor seems normal for all chains, assume that
+	 * there is no significant interference in the environment anymore.
+	 * Re-enable the enforcement of the NF maximum again.
+	 */
+	if (!high_nf_mid)
+		clear_bit(NFCAL_INTF, &cal->cal_flags);
 }
 
 static bool ath9k_hw_get_nf_thresh(struct ath_hw *ah,
@@ -104,24 +182,10 @@ void ath9k_hw_reset_calibration(struct ath_hw *ah,
 	ah->cal_samples = 0;
 }
 
-static s16 ath9k_hw_get_default_nf(struct ath_hw *ah,
-				   struct ath9k_channel *chan)
-{
-	struct ath_nf_limits *limit;
-
-	if (!chan || IS_CHAN_2GHZ(chan))
-		limit = &ah->nf_2g;
-	else
-		limit = &ah->nf_5g;
-
-	return limit->nominal;
-}
-
 /* This is done for the currently configured channel */
 bool ath9k_hw_reset_calvalid(struct ath_hw *ah)
 {
 	struct ath_common *common = ath9k_hw_common(ah);
-	struct ieee80211_conf *conf = &common->hw->conf;
 	struct ath9k_cal_list *currCal = ah->cal_list_curr;
 
 	if (!ah->caldata)
@@ -134,18 +198,16 @@ bool ath9k_hw_reset_calvalid(struct ath_hw *ah)
 		return true;
 
 	if (currCal->calState != CAL_DONE) {
-		ath_print(common, ATH_DBG_CALIBRATE,
-			  "Calibration state incorrect, %d\n",
-			  currCal->calState);
+		ath_dbg(common, CALIBRATE, "Calibration state incorrect, %d\n",
+			currCal->calState);
 		return true;
 	}
 
-	if (!ath9k_hw_iscal_supported(ah, currCal->calData->calType))
+	if (!(ah->supp_cals & currCal->calData->calType))
 		return true;
 
-	ath_print(common, ATH_DBG_CALIBRATE,
-		  "Resetting Cal %d state for channel %u\n",
-		  currCal->calData->calType, conf->channel->center_freq);
+	ath_dbg(common, CALIBRATE, "Resetting Cal %d state for channel %u\n",
+		currCal->calData->calType, ah->curchan->chan->center_freq);
 
 	ah->caldata->CalValid &= ~currCal->calData->calType;
 	currCal->calState = CAL_WAITING;
@@ -157,7 +219,7 @@ EXPORT_SYMBOL(ath9k_hw_reset_calvalid);
 void ath9k_hw_start_nfcal(struct ath_hw *ah, bool update)
 {
 	if (ah->caldata)
-		ah->caldata->nfcal_pending = true;
+		set_bit(NFCAL_PENDING, &ah->caldata->cal_flags);
 
 	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
 		    AR_PHY_AGC_CONTROL_ENABLE_NF);
@@ -188,6 +250,9 @@ void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
 		if (chainmask & (1 << i)) {
 			s16 nfval;
 
+			if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan))
+				continue;
+
 			if (h)
 				nfval = h[i].privNF;
 			else
@@ -216,7 +281,7 @@ void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
 	 * since 250us often results in NF load timeout and causes deaf
 	 * condition during stress testing 12/12/2009
 	 */
-	for (j = 0; j < 1000; j++) {
+	for (j = 0; j < 10000; j++) {
 		if ((REG_READ(ah, AR_PHY_AGC_CONTROL) &
 		     AR_PHY_AGC_CONTROL_NF) == 0)
 			break;
@@ -232,10 +297,10 @@ void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
 	 * here, the baseband nf cal will just be capped by our present
 	 * noisefloor until the next calibration timer.
 	 */
-	if (j == 1000) {
-		ath_print(common, ATH_DBG_ANY, "Timeout while waiting for nf "
-			  "to load: AR_PHY_AGC_CONTROL=0x%x\n",
-			  REG_READ(ah, AR_PHY_AGC_CONTROL));
+	if (j == 10000) {
+		ath_dbg(common, ANY,
+			"Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x%x\n",
+			REG_READ(ah, AR_PHY_AGC_CONTROL));
 		return;
 	}
 
@@ -247,6 +312,9 @@ void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
 	ENABLE_REGWRITE_BUFFER(ah);
 	for (i = 0; i < NUM_NF_READINGS; i++) {
 		if (chainmask & (1 << i)) {
+			if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan))
+				continue;
+
 			val = REG_READ(ah, ah->nf_regs[i]);
 			val &= 0xFFFFFE00;
 			val |= (((u32) (-50) << 1) & 0x1ff);
@@ -254,7 +322,6 @@ void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
 		}
 	}
 	REGWRITE_BUFFER_FLUSH(ah);
-	DISABLE_REGWRITE_BUFFER(ah);
 }
 
 
@@ -273,19 +340,19 @@ static void ath9k_hw_nf_sanitize(struct ath_hw *ah, s16 *nf)
 		if (!nf[i])
 			continue;
 
-		ath_print(common, ATH_DBG_CALIBRATE,
-			  "NF calibrated [%s] [chain %d] is %d\n",
-			  (i >= 3 ? "ext" : "ctl"), i % 3, nf[i]);
+		ath_dbg(common, CALIBRATE,
+			"NF calibrated [%s] [chain %d] is %d\n",
+			(i >= 3 ? "ext" : "ctl"), i % 3, nf[i]);
 
 		if (nf[i] > limit->max) {
-			ath_print(common, ATH_DBG_CALIBRATE,
-				  "NF[%d] (%d) > MAX (%d), correcting to MAX",
-				  i, nf[i], limit->max);
+			ath_dbg(common, CALIBRATE,
+				"NF[%d] (%d) > MAX (%d), correcting to MAX\n",
+				i, nf[i], limit->max);
 			nf[i] = limit->max;
 		} else if (nf[i] < limit->min) {
-			ath_print(common, ATH_DBG_CALIBRATE,
-				  "NF[%d] (%d) < MIN (%d), correcting to NOM",
-				  i, nf[i], limit->min);
+			ath_dbg(common, CALIBRATE,
+				"NF[%d] (%d) < MIN (%d), correcting to NOM\n",
+				i, nf[i], limit->min);
 			nf[i] = limit->nominal;
 		}
 	}
@@ -300,36 +367,35 @@ bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan)
 	struct ieee80211_channel *c = chan->chan;
 	struct ath9k_hw_cal_data *caldata = ah->caldata;
 
-	if (!caldata)
+	if (REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF) {
+		ath_dbg(common, CALIBRATE,
+			"NF did not complete in calibration window\n");
 		return false;
+	}
 
-	chan->channelFlags &= (~CHANNEL_CW_INT);
-	if (REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF) {
-		ath_print(common, ATH_DBG_CALIBRATE,
-			  "NF did not complete in calibration window\n");
-		nf = 0;
-		caldata->rawNoiseFloor = nf;
+	ath9k_hw_do_getnf(ah, nfarray);
+	ath9k_hw_nf_sanitize(ah, nfarray);
+	nf = nfarray[0];
+	if (ath9k_hw_get_nf_thresh(ah, c->band, &nfThresh)
+	    && nf > nfThresh) {
+		ath_dbg(common, CALIBRATE,
+			"noise floor failed detected; detected %d, threshold %d\n",
+			nf, nfThresh);
+	}
+
+	if (!caldata) {
+		chan->noisefloor = nf;
 		return false;
-	} else {
-		ath9k_hw_do_getnf(ah, nfarray);
-		ath9k_hw_nf_sanitize(ah, nfarray);
-		nf = nfarray[0];
-		if (ath9k_hw_get_nf_thresh(ah, c->band, &nfThresh)
-		    && nf > nfThresh) {
-			ath_print(common, ATH_DBG_CALIBRATE,
-				  "noise floor failed detected; "
-				  "detected %d, threshold %d\n",
-				  nf, nfThresh);
-			chan->channelFlags |= CHANNEL_CW_INT;
-		}
 	}
 
 	h = caldata->nfCalHist;
-	caldata->nfcal_pending = false;
-	ath9k_hw_update_nfcal_hist_buffer(h, nfarray);
-	caldata->rawNoiseFloor = h[0].privNF;
+	clear_bit(NFCAL_PENDING, &caldata->cal_flags);
+	ath9k_hw_update_nfcal_hist_buffer(ah, caldata, nfarray);
+	chan->noisefloor = h[0].privNF;
+	ah->noise = ath9k_hw_getchan_noise(ah, chan, chan->noisefloor);
 	return true;
 }
+EXPORT_SYMBOL(ath9k_hw_getnf);
 
 void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
 				  struct ath9k_channel *chan)
@@ -338,9 +404,8 @@ void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
 	s16 default_nf;
 	int i, j;
 
-	if (!ah->caldata)
-		return;
-
+	ah->caldata->channel = chan->channel;
+	ah->caldata->channelFlags = chan->channelFlags;
 	h = ah->caldata->nfCalHist;
 	default_nf = ath9k_hw_get_default_nf(ah, chan);
 	for (i = 0; i < NUM_NF_READINGS; i++) {
@@ -353,11 +418,28 @@ void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
 	}
 }
 
-s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan)
+
+void ath9k_hw_bstuck_nfcal(struct ath_hw *ah)
 {
-	if (!ah->caldata || !ah->caldata->rawNoiseFloor)
-		return ath9k_hw_get_default_nf(ah, chan);
+	struct ath9k_hw_cal_data *caldata = ah->caldata;
+
+	if (unlikely(!caldata))
+		return;
+
+	/*
+	 * If beacons are stuck, the most likely cause is interference.
+	 * Triggering a noise floor calibration at this point helps the
+	 * hardware adapt to a noisy environment much faster.
+	 * To ensure that we recover from stuck beacons quickly, let
+	 * the baseband update the internal NF value itself, similar to
+	 * what is being done after a full reset.
+	 */
+	if (!test_bit(NFCAL_PENDING, &caldata->cal_flags))
+		ath9k_hw_start_nfcal(ah, true);
+	else if (!(REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF))
+		ath9k_hw_getnf(ah, ah->curchan);
 
-	return ah->caldata->rawNoiseFloor;
+	set_bit(NFCAL_INTF, &caldata->cal_flags);
 }
-EXPORT_SYMBOL(ath9k_hw_getchan_noise);
+EXPORT_SYMBOL(ath9k_hw_bstuck_nfcal);
+