drivers/net/wireless/ath/ath9k/calib.c - kernel/skids - Git at Google

 /*
  * Copyright (c) 2008-2009 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
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */

 #include "hw.h"
 #include "hw-ops.h"

 /* Common calibration code */

 /* We can tune this as we go by monitoring really low values */
 #define ATH9K_NF_TOO_LOW	-60

 /* AR5416 may return very high value (like -31 dBm), in those cases the nf
  * is incorrect and we should use the static NF value. Later we can try to
  * find out why they are reporting these values */

 static bool ath9k_hw_nf_in_range(struct ath_hw *ah, s16 nf)
 {
 	if (nf > ATH9K_NF_TOO_LOW) {
 		ath_print(ath9k_hw_common(ah), ATH_DBG_CALIBRATE,
 			  "noise floor value detected (%d) is "
 			  "lower than what we think is a "
 			  "reasonable value (%d)\n",
 			  nf, ATH9K_NF_TOO_LOW);
 		return false;
 	}
 	return true;
 }

 static int16_t ath9k_hw_get_nf_hist_mid(int16_t *nfCalBuffer)
 {
 	int16_t nfval;
 	int16_t sort[ATH9K_NF_CAL_HIST_MAX];
 	int i, j;

 	for (i = 0; i < ATH9K_NF_CAL_HIST_MAX; i++)
 		sort[i] = nfCalBuffer[i];

 	for (i = 0; i < ATH9K_NF_CAL_HIST_MAX - 1; i++) {
 		for (j = 1; j < ATH9K_NF_CAL_HIST_MAX - i; j++) {
 			if (sort[j] > sort[j - 1]) {
 				nfval = sort[j];
 				sort[j] = sort[j - 1];
 				sort[j - 1] = nfval;
 			}
 		}
 	}
 	nfval = sort[(ATH9K_NF_CAL_HIST_MAX - 1) >> 1];

 	return nfval;
 }

 static void ath9k_hw_update_nfcal_hist_buffer(struct ath9k_nfcal_hist *h,
 					      int16_t *nfarray)
 {
 	int i;

 	for (i = 0; i < NUM_NF_READINGS; i++) {
 		h[i].nfCalBuffer[h[i].currIndex] = nfarray[i];

 		if (++h[i].currIndex >= ATH9K_NF_CAL_HIST_MAX)
 			h[i].currIndex = 0;

 		if (h[i].invalidNFcount > 0) {
 			if (nfarray[i] < AR_PHY_CCA_MIN_BAD_VALUE ||
 			    nfarray[i] > AR_PHY_CCA_MAX_HIGH_VALUE) {
 				h[i].invalidNFcount = ATH9K_NF_CAL_HIST_MAX;
 			} else {
 				h[i].invalidNFcount--;
 				h[i].privNF = nfarray[i];
 			}
 		} else {
 			h[i].privNF =
 				ath9k_hw_get_nf_hist_mid(h[i].nfCalBuffer);
 		}
 	}
 }

 static bool ath9k_hw_get_nf_thresh(struct ath_hw *ah,
 				   enum ieee80211_band band,
 				   int16_t *nft)
 {
 	switch (band) {
 	case IEEE80211_BAND_5GHZ:
 		*nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_5);
 		break;
 	case IEEE80211_BAND_2GHZ:
 		*nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_2);
 		break;
 	default:
 		BUG_ON(1);
 		return false;
 	}

 	return true;
 }

 void ath9k_hw_reset_calibration(struct ath_hw *ah,
 				struct ath9k_cal_list *currCal)
 {
 	int i;

 	ath9k_hw_setup_calibration(ah, currCal);

 	currCal->calState = CAL_RUNNING;

 	for (i = 0; i < AR5416_MAX_CHAINS; i++) {
 		ah->meas0.sign[i] = 0;
 		ah->meas1.sign[i] = 0;
 		ah->meas2.sign[i] = 0;
 		ah->meas3.sign[i] = 0;
 	}

 	ah->cal_samples = 0;
 }

 /* 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->curchan)
 		return true;

 	if (!AR_SREV_9100(ah) && !AR_SREV_9160_10_OR_LATER(ah))
 		return true;

 	if (currCal == NULL)
 		return true;

 	if (currCal->calState != CAL_DONE) {
 		ath_print(common, ATH_DBG_CALIBRATE,
 			  "Calibration state incorrect, %d\n",
 			  currCal->calState);
 		return true;
 	}

 	if (!ath9k_hw_iscal_supported(ah, 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);

 	ah->curchan->CalValid &= ~currCal->calData->calType;
 	currCal->calState = CAL_WAITING;

 	return false;
 }
 EXPORT_SYMBOL(ath9k_hw_reset_calvalid);

 void ath9k_hw_start_nfcal(struct ath_hw *ah)
 {
 	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
 		    AR_PHY_AGC_CONTROL_ENABLE_NF);
 	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
 		    AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
 	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF);
 }

 int16_t ath9k_hw_getnf(struct ath_hw *ah,
 		       struct ath9k_channel *chan)
 {
 	struct ath_common *common = ath9k_hw_common(ah);
 	int16_t nf, nfThresh;
 	int16_t nfarray[NUM_NF_READINGS] = { 0 };
 	struct ath9k_nfcal_hist *h;
 	struct ieee80211_channel *c = chan->chan;

 	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;
 		chan->rawNoiseFloor = nf;
 		return chan->rawNoiseFloor;
 	} else {
 		ath9k_hw_do_getnf(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 = ah->nfCalHist;

 	ath9k_hw_update_nfcal_hist_buffer(h, nfarray);
 	chan->rawNoiseFloor = h[0].privNF;

 	return chan->rawNoiseFloor;
 }

 void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah)
 {
 	int i, j;
 	s16 noise_floor;

 	if (AR_SREV_9280(ah))
 		noise_floor = AR_PHY_CCA_MAX_AR9280_GOOD_VALUE;
 	else if (AR_SREV_9285(ah) || AR_SREV_9271(ah))
 		noise_floor = AR_PHY_CCA_MAX_AR9285_GOOD_VALUE;
 	else if (AR_SREV_9287(ah))
 		noise_floor = AR_PHY_CCA_MAX_AR9287_GOOD_VALUE;
 	else
 		noise_floor = AR_PHY_CCA_MAX_AR5416_GOOD_VALUE;

 	for (i = 0; i < NUM_NF_READINGS; i++) {
 		ah->nfCalHist[i].currIndex = 0;
 		ah->nfCalHist[i].privNF = noise_floor;
 		ah->nfCalHist[i].invalidNFcount =
 			AR_PHY_CCA_FILTERWINDOW_LENGTH;
 		for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++) {
 			ah->nfCalHist[i].nfCalBuffer[j] = noise_floor;
 		}
 	}
 }

 s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan)
 {
 	s16 nf;

 	if (chan->rawNoiseFloor == 0)
 		nf = -96;
 	else
 		nf = chan->rawNoiseFloor;

 	if (!ath9k_hw_nf_in_range(ah, nf))
 		nf = ATH_DEFAULT_NOISE_FLOOR;

 	return nf;
 }
 EXPORT_SYMBOL(ath9k_hw_getchan_noise);
	/*
	* Copyright (c) 2008-2009 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
	* copyright notice and this permission notice appear in all copies.
	*
	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	*/

	#include "hw.h"
	#include "hw-ops.h"

	/* Common calibration code */

	/* We can tune this as we go by monitoring really low values */
	#define ATH9K_NF_TOO_LOW -60

	/* AR5416 may return very high value (like -31 dBm), in those cases the nf
	* is incorrect and we should use the static NF value. Later we can try to
	* find out why they are reporting these values */

	static bool ath9k_hw_nf_in_range(struct ath_hw *ah, s16 nf)
	{
	if (nf > ATH9K_NF_TOO_LOW) {
	ath_print(ath9k_hw_common(ah), ATH_DBG_CALIBRATE,
	"noise floor value detected (%d) is "
	"lower than what we think is a "
	"reasonable value (%d)\n",
	nf, ATH9K_NF_TOO_LOW);
	return false;
	}
	return true;
	}

	static int16_t ath9k_hw_get_nf_hist_mid(int16_t *nfCalBuffer)
	{
	int16_t nfval;
	int16_t sort[ATH9K_NF_CAL_HIST_MAX];
	int i, j;

	for (i = 0; i < ATH9K_NF_CAL_HIST_MAX; i++)
	sort[i] = nfCalBuffer[i];

	for (i = 0; i < ATH9K_NF_CAL_HIST_MAX - 1; i++) {
	for (j = 1; j < ATH9K_NF_CAL_HIST_MAX - i; j++) {
	if (sort[j] > sort[j - 1]) {
	nfval = sort[j];
	sort[j] = sort[j - 1];
	sort[j - 1] = nfval;
	}
	}
	}
	nfval = sort[(ATH9K_NF_CAL_HIST_MAX - 1) >> 1];

	return nfval;
	}

	static void ath9k_hw_update_nfcal_hist_buffer(struct ath9k_nfcal_hist *h,
	int16_t *nfarray)
	{
	int i;

	for (i = 0; i < NUM_NF_READINGS; i++) {
	h[i].nfCalBuffer[h[i].currIndex] = nfarray[i];

	if (++h[i].currIndex >= ATH9K_NF_CAL_HIST_MAX)
	h[i].currIndex = 0;

	if (h[i].invalidNFcount > 0) {
	if (nfarray[i] < AR_PHY_CCA_MIN_BAD_VALUE \|\|
	nfarray[i] > AR_PHY_CCA_MAX_HIGH_VALUE) {
	h[i].invalidNFcount = ATH9K_NF_CAL_HIST_MAX;
	} else {
	h[i].invalidNFcount--;
	h[i].privNF = nfarray[i];
	}
	} else {
	h[i].privNF =
	ath9k_hw_get_nf_hist_mid(h[i].nfCalBuffer);
	}
	}
	}

	static bool ath9k_hw_get_nf_thresh(struct ath_hw *ah,
	enum ieee80211_band band,
	int16_t *nft)
	{
	switch (band) {
	case IEEE80211_BAND_5GHZ:
	*nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_5);
	break;
	case IEEE80211_BAND_2GHZ:
	*nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_2);
	break;
	default:
	BUG_ON(1);
	return false;
	}

	return true;
	}

	void ath9k_hw_reset_calibration(struct ath_hw *ah,
	struct ath9k_cal_list *currCal)
	{
	int i;

	ath9k_hw_setup_calibration(ah, currCal);

	currCal->calState = CAL_RUNNING;

	for (i = 0; i < AR5416_MAX_CHAINS; i++) {
	ah->meas0.sign[i] = 0;
	ah->meas1.sign[i] = 0;
	ah->meas2.sign[i] = 0;
	ah->meas3.sign[i] = 0;
	}

	ah->cal_samples = 0;
	}

	/* 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->curchan)
	return true;

	if (!AR_SREV_9100(ah) && !AR_SREV_9160_10_OR_LATER(ah))
	return true;

	if (currCal == NULL)
	return true;

	if (currCal->calState != CAL_DONE) {
	ath_print(common, ATH_DBG_CALIBRATE,
	"Calibration state incorrect, %d\n",
	currCal->calState);
	return true;
	}

	if (!ath9k_hw_iscal_supported(ah, 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);

	ah->curchan->CalValid &= ~currCal->calData->calType;
	currCal->calState = CAL_WAITING;

	return false;
	}
	EXPORT_SYMBOL(ath9k_hw_reset_calvalid);

	void ath9k_hw_start_nfcal(struct ath_hw *ah)
	{
	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
	AR_PHY_AGC_CONTROL_ENABLE_NF);
	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
	AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF);
	}

	int16_t ath9k_hw_getnf(struct ath_hw *ah,
	struct ath9k_channel *chan)
	{
	struct ath_common *common = ath9k_hw_common(ah);
	int16_t nf, nfThresh;
	int16_t nfarray[NUM_NF_READINGS] = { 0 };
	struct ath9k_nfcal_hist *h;
	struct ieee80211_channel *c = chan->chan;

	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;
	chan->rawNoiseFloor = nf;
	return chan->rawNoiseFloor;
	} else {
	ath9k_hw_do_getnf(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 = ah->nfCalHist;

	ath9k_hw_update_nfcal_hist_buffer(h, nfarray);
	chan->rawNoiseFloor = h[0].privNF;

	return chan->rawNoiseFloor;
	}

	void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah)
	{
	int i, j;
	s16 noise_floor;

	if (AR_SREV_9280(ah))
	noise_floor = AR_PHY_CCA_MAX_AR9280_GOOD_VALUE;
	else if (AR_SREV_9285(ah) \|\| AR_SREV_9271(ah))
	noise_floor = AR_PHY_CCA_MAX_AR9285_GOOD_VALUE;
	else if (AR_SREV_9287(ah))
	noise_floor = AR_PHY_CCA_MAX_AR9287_GOOD_VALUE;
	else
	noise_floor = AR_PHY_CCA_MAX_AR5416_GOOD_VALUE;

	for (i = 0; i < NUM_NF_READINGS; i++) {
	ah->nfCalHist[i].currIndex = 0;
	ah->nfCalHist[i].privNF = noise_floor;
	ah->nfCalHist[i].invalidNFcount =
	AR_PHY_CCA_FILTERWINDOW_LENGTH;
	for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++) {
	ah->nfCalHist[i].nfCalBuffer[j] = noise_floor;
	}
	}
	}

	s16 ath9k_hw_getchan_noise(struct ath_hw ah, struct ath9k_channel chan)
	{
	s16 nf;

	if (chan->rawNoiseFloor == 0)
	nf = -96;
	else
	nf = chan->rawNoiseFloor;

	if (!ath9k_hw_nf_in_range(ah, nf))
	nf = ATH_DEFAULT_NOISE_FLOOR;

	return nf;
	}
	EXPORT_SYMBOL(ath9k_hw_getchan_noise);