- 根目录:
- drivers
- net
- wireless
- ath
- ath9k
- calib.c
/*
* 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
* 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"
#include <linux/export.h>
/* Common calibration code */
#define ATH9K_NF_TOO_HIGH -60
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 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)
{
s8 noise = ATH_DEFAULT_NOISE_FLOOR;
if (chan && chan->noisefloor) {
s8 delta = chan->noisefloor -
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)
h[i].currIndex = 0;
if (h[i].invalidNFcount > 0) {
h[i].invalidNFcount--;
h[i].privNF = nfarray[i];
} else {
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,
(cal->nfcal_interference ?
"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 (!cal->nfcal_interference)
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)
cal->nfcal_interference = false;
}
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->caldata)
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_dbg(common, CALIBRATE, "Calibration state incorrect, %d\n",
currCal->calState);
return true;
}
if (!(ah->supp_cals & currCal->calData->calType))
return true;
ath_dbg(common, CALIBRATE, "Resetting Cal %d state for channel %u\n",
currCal->calData->calType, conf->channel->center_freq);
ah->caldata->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, bool update)
{
if (ah->caldata)
ah->caldata->nfcal_pending = true;
REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
AR_PHY_AGC_CONTROL_ENABLE_NF);
if (update)
REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL,
AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
else
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);
}
void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
{
struct ath9k_nfcal_hist *h = NULL;
unsigned i, j;
int32_t val;
u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
struct ath_common *common = ath9k_hw_common(ah);
struct ieee80211_conf *conf = &common->hw->conf;
s16 default_nf = ath9k_hw_get_default_nf(ah, chan);
if (ah->caldata)
h = ah->caldata->nfCalHist;
for (i = 0; i < NUM_NF_READINGS; i++) {
if (chainmask & (1 << i)) {
s16 nfval;
if ((i >= AR5416_MAX_CHAINS) && !conf_is_ht40(conf))
continue;
if (h)
nfval = h[i].privNF;
else
nfval = default_nf;
val = REG_READ(ah, ah->nf_regs[i]);
val &= 0xFFFFFE00;
val |= (((u32) nfval << 1) & 0x1ff);
REG_WRITE(ah, ah->nf_regs[i], val);
}
}
/*
* Load software filtered NF value into baseband internal minCCApwr
* variable.
*/
REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL,
AR_PHY_AGC_CONTROL_ENABLE_NF);
REG_CLR_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);
/*
* Wait for load to complete, should be fast, a few 10s of us.
* The max delay was changed from an original 250us to 10000us
* since 250us often results in NF load timeout and causes deaf
* condition during stress testing 12/12/2009
*/
for (j = 0; j < 10000; j++) {
if ((REG_READ(ah, AR_PHY_AGC_CONTROL) &
AR_PHY_AGC_CONTROL_NF) == 0)
break;
udelay(10);
}
/*
* We timed out waiting for the noisefloor to load, probably due to an
* in-progress rx. Simply return here and allow the load plenty of time
* to complete before the next calibration interval. We need to avoid
* trying to load -50 (which happens below) while the previous load is
* still in progress as this can cause rx deafness. Instead by returning
* here, the baseband nf cal will just be capped by our present
* noisefloor until the next calibration timer.
*/
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;
}
/*
* Restore maxCCAPower register parameter again so that we're not capped
* by the median we just loaded. This will be initial (and max) value
* of next noise floor calibration the baseband does.
*/
ENABLE_REGWRITE_BUFFER(ah);
for (i = 0; i < NUM_NF_READINGS; i++) {
if (chainmask & (1 << i)) {
if ((i >= AR5416_MAX_CHAINS) && !conf_is_ht40(conf))
continue;
val = REG_READ(ah, ah->nf_regs[i]);
val &= 0xFFFFFE00;
val |= (((u32) (-50) << 1) & 0x1ff);
REG_WRITE(ah, ah->nf_regs[i], val);
}
}
REGWRITE_BUFFER_FLUSH(ah);
}
static void ath9k_hw_nf_sanitize(struct ath_hw *ah, s16 *nf)
{
struct ath_common *common = ath9k_hw_common(ah);
struct ath_nf_limits *limit;
int i;
if (IS_CHAN_2GHZ(ah->curchan))
limit = &ah->nf_2g;
else
limit = &ah->nf_5g;
for (i = 0; i < NUM_NF_READINGS; i++) {
if (!nf[i])
continue;
ath_dbg(common, CALIBRATE,
"NF calibrated [%s] [chain %d] is %d\n",
(i >= 3 ? "ext" : "ctl"), i % 3, nf[i]);
if (nf[i] > ATH9K_NF_TOO_HIGH) {
ath_dbg(common, CALIBRATE,
"NF[%d] (%d) > MAX (%d), correcting to MAX\n",
i, nf[i], ATH9K_NF_TOO_HIGH);
nf[i] = limit->max;
} else if (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;
}
}
}
bool 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;
struct ath9k_hw_cal_data *caldata = ah->caldata;
chan->channelFlags &= (~CHANNEL_CW_INT);
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;
}
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);
chan->channelFlags |= CHANNEL_CW_INT;
}
if (!caldata) {
chan->noisefloor = nf;
ah->noise = ath9k_hw_getchan_noise(ah, chan);
return false;
}
h = caldata->nfCalHist;
caldata->nfcal_pending = false;
ath9k_hw_update_nfcal_hist_buffer(ah, caldata, nfarray);
chan->noisefloor = h[0].privNF;
ah->noise = ath9k_hw_getchan_noise(ah, chan);
return true;
}
EXPORT_SYMBOL(ath9k_hw_getnf);
void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
struct ath9k_channel *chan)
{
struct ath9k_nfcal_hist *h;
s16 default_nf;
int i, j;
ah->caldata->channel = chan->channel;
ah->caldata->channelFlags = chan->channelFlags & ~CHANNEL_CW_INT;
h = ah->caldata->nfCalHist;
default_nf = ath9k_hw_get_default_nf(ah, chan);
for (i = 0; i < NUM_NF_READINGS; i++) {
h[i].currIndex = 0;
h[i].privNF = default_nf;
h[i].invalidNFcount = AR_PHY_CCA_FILTERWINDOW_LENGTH;
for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++) {
h[i].nfCalBuffer[j] = default_nf;
}
}
}
void ath9k_hw_bstuck_nfcal(struct ath_hw *ah)
{
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 (!caldata->nfcal_pending)
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);
caldata->nfcal_interference = true;
}
EXPORT_SYMBOL(ath9k_hw_bstuck_nfcal);