/*
* 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);
}
}
return;
}
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);
