/*
* 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 <linux/kernel.h>
#include <linux/export.h>
#include "hw.h"
#include "hw-ops.h"
struct ani_ofdm_level_entry {
int spur_immunity_level;
int fir_step_level;
int ofdm_weak_signal_on;
};
/* values here are relative to the INI */
/*
* Legend:
*
* SI: Spur immunity
* FS: FIR Step
* WS: OFDM / CCK Weak Signal detection
* MRC-CCK: Maximal Ratio Combining for CCK
*/
static const struct ani_ofdm_level_entry ofdm_level_table[] = {
/* SI FS WS */
{ 0, 0, 1 }, /* lvl 0 */
{ 1, 1, 1 }, /* lvl 1 */
{ 2, 2, 1 }, /* lvl 2 */
{ 3, 2, 1 }, /* lvl 3 (default) */
{ 4, 3, 1 }, /* lvl 4 */
{ 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 */
};
#define ATH9K_ANI_OFDM_NUM_LEVEL \
ARRAY_SIZE(ofdm_level_table)
#define ATH9K_ANI_OFDM_MAX_LEVEL \
(ATH9K_ANI_OFDM_NUM_LEVEL-1)
#define ATH9K_ANI_OFDM_DEF_LEVEL \
3 /* default level - matches the INI settings */
/*
* MRC (Maximal Ratio Combining) has always been used with multi-antenna ofdm.
* With OFDM for single stream you just add up all antenna inputs, you're
* only interested in what you get after FFT. Signal alignment is also not
* required for OFDM because any phase difference adds up in the frequency
* domain.
*
* MRC requires extra work for use with CCK. You need to align the antenna
* signals from the different antenna before you can add the signals together.
* You need alignment of signals as CCK is in time domain, so addition can cancel
* your signal completely if phase is 180 degrees (think of adding sine waves).
* You also need to remove noise before the addition and this is where ANI
* MRC CCK comes into play. One of the antenna inputs may be stronger but
* lower SNR, so just adding after alignment can be dangerous.
*
* Regardless of alignment in time, the antenna signals add constructively after
* FFT and improve your reception. For more information:
*
* http://en.wikipedia.org/wiki/Maximal-ratio_combining
*/
struct ani_cck_level_entry {
int fir_step_level;
int mrc_cck_on;
};
static const struct ani_cck_level_entry cck_level_table[] = {
/* FS MRC-CCK */
{ 0, 1 }, /* lvl 0 */
{ 1, 1 }, /* lvl 1 */
{ 2, 1 }, /* lvl 2 (default) */
{ 3, 1 }, /* lvl 3 */
{ 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) */
};
#define ATH9K_ANI_CCK_NUM_LEVEL \
ARRAY_SIZE(cck_level_table)
#define ATH9K_ANI_CCK_MAX_LEVEL \
(ATH9K_ANI_CCK_NUM_LEVEL-1)
#define ATH9K_ANI_CCK_MAX_LEVEL_LOW_RSSI \
(ATH9K_ANI_CCK_NUM_LEVEL-3)
#define ATH9K_ANI_CCK_DEF_LEVEL \
2 /* default level - matches the INI settings */
static void ath9k_hw_update_mibstats(struct ath_hw *ah,
struct ath9k_mib_stats *stats)
{
u32 addr[5] = {AR_RTS_OK, AR_RTS_FAIL, AR_ACK_FAIL,
AR_FCS_FAIL, AR_BEACON_CNT};
u32 data[5];
REG_READ_MULTI(ah, &addr[0], &data[0], 5);
/* AR_RTS_OK */
stats->rts_good += data[0];
/* AR_RTS_FAIL */
stats->rts_bad += data[1];
/* AR_ACK_FAIL */
stats->ackrcv_bad += data[2];
/* AR_FCS_FAIL */
stats->fcs_bad += data[3];
/* AR_BEACON_CNT */
stats->beacons += data[4];
}
static void ath9k_ani_restart(struct ath_hw *ah)
{
struct ar5416AniState *aniState = &ah->ani;
aniState->listenTime = 0;
ENABLE_REGWRITE_BUFFER(ah);
REG_WRITE(ah, AR_PHY_ERR_1, 0);
REG_WRITE(ah, AR_PHY_ERR_2, 0);
REG_WRITE(ah, AR_PHY_ERR_MASK_1, AR_PHY_ERR_OFDM_TIMING);
REG_WRITE(ah, AR_PHY_ERR_MASK_2, AR_PHY_ERR_CCK_TIMING);
REGWRITE_BUFFER_FLUSH(ah);
ath9k_hw_update_mibstats(ah, &ah->ah_mibStats);
aniState->ofdmPhyErrCount = 0;
aniState->cckPhyErrCount = 0;
}
/* Adjust the OFDM Noise Immunity Level */
static void ath9k_hw_set_ofdm_nil(struct ath_hw *ah, u8 immunityLevel,
bool scan)
{
struct ar5416AniState *aniState = &ah->ani;
struct ath_common *common = ath9k_hw_common(ah);
const struct ani_ofdm_level_entry *entry_ofdm;
const struct ani_cck_level_entry *entry_cck;
bool weak_sig;
ath_dbg(common, ANI, "**** ofdmlevel %d=>%d, rssi=%d[lo=%d hi=%d]\n",
aniState->ofdmNoiseImmunityLevel,
immunityLevel, BEACON_RSSI(ah),
ATH9K_ANI_RSSI_THR_LOW,
ATH9K_ANI_RSSI_THR_HIGH);
if (AR_SREV_9100(ah) && immunityLevel < ATH9K_ANI_OFDM_DEF_LEVEL)
immunityLevel = ATH9K_ANI_OFDM_DEF_LEVEL;
if (!scan)
aniState->ofdmNoiseImmunityLevel = immunityLevel;
entry_ofdm = &ofdm_level_table[aniState->ofdmNoiseImmunityLevel];
entry_cck = &cck_level_table[aniState->cckNoiseImmunityLevel];
if (aniState->spurImmunityLevel != entry_ofdm->spur_immunity_level)
ath9k_hw_ani_control(ah,
ATH9K_ANI_SPUR_IMMUNITY_LEVEL,
entry_ofdm->spur_immunity_level);
if (aniState->firstepLevel != entry_ofdm->fir_step_level &&
entry_ofdm->fir_step_level >= entry_cck->fir_step_level)
ath9k_hw_ani_control(ah,
ATH9K_ANI_FIRSTEP_LEVEL,
entry_ofdm->fir_step_level);
weak_sig = entry_ofdm->ofdm_weak_signal_on;
if (ah->opmode == NL80211_IFTYPE_STATION &&
BEACON_RSSI(ah) <= ATH9K_ANI_RSSI_THR_HIGH)
weak_sig = true;
/*
* Newer chipsets are better at dealing with high PHY error counts -
* keep weak signal detection enabled when no RSSI threshold is
* available to determine if it is needed (mode != STA)
*/
else if (AR_SREV_9300_20_OR_LATER(ah) &&
ah->opmode != NL80211_IFTYPE_STATION)
weak_sig = true;
/* Older chipsets are more sensitive to high PHY error counts */
else if (!AR_SREV_9300_20_OR_LATER(ah) &&
aniState->ofdmNoiseImmunityLevel >= 8)
weak_sig = false;
if (aniState->ofdmWeakSigDetect != weak_sig)
ath9k_hw_ani_control(ah, ATH9K_ANI_OFDM_WEAK_SIGNAL_DETECTION,
weak_sig);
if (!AR_SREV_9300_20_OR_LATER(ah))
return;
if (aniState->ofdmNoiseImmunityLevel >= ATH9K_ANI_OFDM_DEF_LEVEL) {
ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH;
ah->config.ofdm_trig_low = ATH9K_ANI_OFDM_TRIG_LOW_ABOVE_INI;
} else {
ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH_BELOW_INI;
ah->config.ofdm_trig_low = ATH9K_ANI_OFDM_TRIG_LOW;
}
}
static void ath9k_hw_ani_ofdm_err_trigger(struct ath_hw *ah)
{
struct ar5416AniState *aniState = &ah->ani;
if (aniState->ofdmNoiseImmunityLevel < ATH9K_ANI_OFDM_MAX_LEVEL)
ath9k_hw_set_ofdm_nil(ah, aniState->ofdmNoiseImmunityLevel + 1, false);
}
/*
* Set the ANI settings to match an CCK level.
*/
static void ath9k_hw_set_cck_nil(struct ath_hw *ah, u_int8_t immunityLevel,
bool scan)
{
struct ar5416AniState *aniState = &ah->ani;
struct ath_common *common = ath9k_hw_common(ah);
const struct ani_ofdm_level_entry *entry_ofdm;
const struct ani_cck_level_entry *entry_cck;
ath_dbg(common, ANI, "**** ccklevel %d=>%d, rssi=%d[lo=%d hi=%d]\n",
aniState->cckNoiseImmunityLevel, immunityLevel,
BEACON_RSSI(ah), ATH9K_ANI_RSSI_THR_LOW,
ATH9K_ANI_RSSI_THR_HIGH);
if (AR_SREV_9100(ah) && immunityLevel < ATH9K_ANI_CCK_DEF_LEVEL)
immunityLevel = ATH9K_ANI_CCK_DEF_LEVEL;
if (ah->opmode == NL80211_IFTYPE_STATION &&
BEACON_RSSI(ah) <= ATH9K_ANI_RSSI_THR_LOW &&
immunityLevel > ATH9K_ANI_CCK_MAX_LEVEL_LOW_RSSI)
immunityLevel = ATH9K_ANI_CCK_MAX_LEVEL_LOW_RSSI;
if (!scan)
aniState->cckNoiseImmunityLevel = immunityLevel;
entry_ofdm = &ofdm_level_table[aniState->ofdmNoiseImmunityLevel];
entry_cck = &cck_level_table[aniState->cckNoiseImmunityLevel];
if (aniState->firstepLevel != entry_cck->fir_step_level &&
entry_cck->fir_step_level >= entry_ofdm->fir_step_level)
ath9k_hw_ani_control(ah,
ATH9K_ANI_FIRSTEP_LEVEL,
entry_cck->fir_step_level);
/* Skip MRC CCK for pre AR9003 families */
if (!AR_SREV_9300_20_OR_LATER(ah) || AR_SREV_9485(ah) ||
AR_SREV_9565(ah) || AR_SREV_9561(ah))
return;
if (aniState->mrcCCK != entry_cck->mrc_cck_on)
ath9k_hw_ani_control(ah,
ATH9K_ANI_MRC_CCK,
entry_cck->mrc_cck_on);
}
static void ath9k_hw_ani_cck_err_trigger(struct ath_hw *ah)
{
struct ar5416AniState *aniState = &ah->ani;
if (aniState->cckNoiseImmunityLevel < ATH9K_ANI_CCK_MAX_LEVEL)
ath9k_hw_set_cck_nil(ah, aniState->cckNoiseImmunityLevel + 1,
false);
}
/*
* only lower either OFDM or CCK errors per turn
* we lower the other one next time
*/
static void ath9k_hw_ani_lower_immunity(struct ath_hw *ah)
{
struct ar5416AniState *aniState = &ah->ani;
/* lower OFDM noise immunity */
if (aniState->ofdmNoiseImmunityLevel > 0 &&
(aniState->ofdmsTurn || aniState->cckNoiseImmunityLevel == 0)) {
ath9k_hw_set_ofdm_nil(ah, aniState->ofdmNoiseImmunityLevel - 1,
false);
return;
}
/* lower CCK noise immunity */
if (aniState->cckNoiseImmunityLevel > 0)
ath9k_hw_set_cck_nil(ah, aniState->cckNoiseImmunityLevel - 1,
false);
}
/*
* Restore the ANI parameters in the HAL and reset the statistics.
* This routine should be called for every hardware reset and for
* every channel change.
*/
void ath9k_ani_reset(struct ath_hw *ah, bool is_scanning)
{
struct ar5416AniState *aniState = &ah->ani;
struct ath9k_channel *chan = ah->curchan;
struct ath_common *common = ath9k_hw_common(ah);
int ofdm_nil, cck_nil;
if (!chan)
return;
BUG_ON(aniState == NULL);
ah->stats.ast_ani_reset++;
ofdm_nil = max_t(int, ATH9K_ANI_OFDM_DEF_LEVEL,
aniState->ofdmNoiseImmunityLevel);
cck_nil = max_t(int, ATH9K_ANI_CCK_DEF_LEVEL,
aniState->cckNoiseImmunityLevel);
if (is_scanning ||
(ah->opmode != NL80211_IFTYPE_STATION &&
ah->opmode != NL80211_IFTYPE_ADHOC)) {
/*
* If we're scanning or in AP mode, the defaults (ini)
* should be in place. For an AP we assume the historical
* levels for this channel are probably outdated so start
* from defaults instead.
*/
if (aniState->ofdmNoiseImmunityLevel !=
ATH9K_ANI_OFDM_DEF_LEVEL ||
aniState->cckNoiseImmunityLevel !=
ATH9K_ANI_CCK_DEF_LEVEL) {
ath_dbg(common, ANI,
"Restore defaults: opmode %u chan %d Mhz is_scanning=%d ofdm:%d cck:%d\n",
ah->opmode,
chan->channel,
is_scanning,
aniState->ofdmNoiseImmunityLevel,
aniState->cckNoiseImmunityLevel);
ofdm_nil = ATH9K_ANI_OFDM_DEF_LEVEL;
cck_nil = ATH9K_ANI_CCK_DEF_LEVEL;
}
} else {
/*
* restore historical levels for this channel
*/
ath_dbg(common, ANI,
"Restore history: opmode %u chan %d Mhz is_scanning=%d ofdm:%d cck:%d\n",
ah->opmode,
chan->channel,
is_scanning,
aniState->ofdmNoiseImmunityLevel,
aniState->cckNoiseImmunityLevel);
}
ath9k_hw_set_ofdm_nil(ah, ofdm_nil, is_scanning);
ath9k_hw_set_cck_nil(ah, cck_nil, is_scanning);
ath9k_ani_restart(ah);
}
static bool ath9k_hw_ani_read_counters(struct ath_hw *ah)
{
struct ath_common *common = ath9k_hw_common(ah);
struct ar5416AniState *aniState = &ah->ani;
u32 phyCnt1, phyCnt2;
int32_t listenTime;
ath_hw_cycle_counters_update(common);
listenTime = ath_hw_get_listen_time(common);
if (listenTime <= 0) {
ah->stats.ast_ani_lneg_or_lzero++;
ath9k_ani_restart(ah);
return false;
}
aniState->listenTime += listenTime;
ath9k_hw_update_mibstats(ah, &ah->ah_mibStats);
phyCnt1 = REG_READ(ah, AR_PHY_ERR_1);
phyCnt2 = REG_READ(ah, AR_PHY_ERR_2);
ah->stats.ast_ani_ofdmerrs += phyCnt1 - aniState->ofdmPhyErrCount;
aniState->ofdmPhyErrCount = phyCnt1;
ah->stats.ast_ani_cckerrs += phyCnt2 - aniState->cckPhyErrCount;
aniState->cckPhyErrCount = phyCnt2;
return true;
}
void ath9k_hw_ani_monitor(struct ath_hw *ah, struct ath9k_channel *chan)
{
struct ar5416AniState *aniState = &ah->ani;
struct ath_common *common = ath9k_hw_common(ah);
u32 ofdmPhyErrRate, cckPhyErrRate;
if (!ath9k_hw_ani_read_counters(ah))
return;
ofdmPhyErrRate = aniState->ofdmPhyErrCount * 1000 /
aniState->listenTime;
cckPhyErrRate = aniState->cckPhyErrCount * 1000 /
aniState->listenTime;
ath_dbg(common, ANI,
"listenTime=%d OFDM:%d errs=%d/s CCK:%d errs=%d/s ofdm_turn=%d\n",
aniState->listenTime,
aniState->ofdmNoiseImmunityLevel,
ofdmPhyErrRate, aniState->cckNoiseImmunityLevel,
cckPhyErrRate, aniState->ofdmsTurn);
if (aniState->listenTime > ah->aniperiod) {
if (cckPhyErrRate < ah->config.cck_trig_low &&
ofdmPhyErrRate < ah->config.ofdm_trig_low) {
ath9k_hw_ani_lower_immunity(ah);
aniState->ofdmsTurn = !aniState->ofdmsTurn;
} else if (ofdmPhyErrRate > ah->config.ofdm_trig_high) {
ath9k_hw_ani_ofdm_err_trigger(ah);
aniState->ofdmsTurn = false;
} else if (cckPhyErrRate > ah->config.cck_trig_high) {
ath9k_hw_ani_cck_err_trigger(ah);
aniState->ofdmsTurn = true;
} else
return;
ath9k_ani_restart(ah);
}
}
EXPORT_SYMBOL(ath9k_hw_ani_monitor);
void ath9k_enable_mib_counters(struct ath_hw *ah)
{
struct ath_common *common = ath9k_hw_common(ah);
ath_dbg(common, ANI, "Enable MIB counters\n");
ath9k_hw_update_mibstats(ah, &ah->ah_mibStats);
ENABLE_REGWRITE_BUFFER(ah);
REG_WRITE(ah, AR_FILT_OFDM, 0);
REG_WRITE(ah, AR_FILT_CCK, 0);
REG_WRITE(ah, AR_MIBC,
~(AR_MIBC_COW | AR_MIBC_FMC | AR_MIBC_CMC | AR_MIBC_MCS)
& 0x0f);
REG_WRITE(ah, AR_PHY_ERR_MASK_1, AR_PHY_ERR_OFDM_TIMING);
REG_WRITE(ah, AR_PHY_ERR_MASK_2, AR_PHY_ERR_CCK_TIMING);
REGWRITE_BUFFER_FLUSH(ah);
}
/* Freeze the MIB counters, get the stats and then clear them */
void ath9k_hw_disable_mib_counters(struct ath_hw *ah)
{
struct ath_common *common = ath9k_hw_common(ah);
ath_dbg(common, ANI, "Disable MIB counters\n");
REG_WRITE(ah, AR_MIBC, AR_MIBC_FMC);
ath9k_hw_update_mibstats(ah, &ah->ah_mibStats);
REG_WRITE(ah, AR_MIBC, AR_MIBC_CMC);
REG_WRITE(ah, AR_FILT_OFDM, 0);
REG_WRITE(ah, AR_FILT_CCK, 0);
}
EXPORT_SYMBOL(ath9k_hw_disable_mib_counters);
void ath9k_hw_ani_init(struct ath_hw *ah)
{
struct ath_common *common = ath9k_hw_common(ah);
struct ar5416AniState *ani = &ah->ani;
ath_dbg(common, ANI, "Initialize ANI\n");
if (AR_SREV_9300_20_OR_LATER(ah)) {
ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH;
ah->config.ofdm_trig_low = ATH9K_ANI_OFDM_TRIG_LOW;
ah->config.cck_trig_high = ATH9K_ANI_CCK_TRIG_HIGH;
ah->config.cck_trig_low = ATH9K_ANI_CCK_TRIG_LOW;
} else {
ah->config.ofdm_trig_high = ATH9K_ANI_OFDM_TRIG_HIGH_OLD;
ah->config.ofdm_trig_low = ATH9K_ANI_OFDM_TRIG_LOW_OLD;
ah->config.cck_trig_high = ATH9K_ANI_CCK_TRIG_HIGH_OLD;
ah->config.cck_trig_low = ATH9K_ANI_CCK_TRIG_LOW_OLD;
}
ani->spurImmunityLevel = ATH9K_ANI_SPUR_IMMUNE_LVL;
ani->firstepLevel = ATH9K_ANI_FIRSTEP_LVL;
ani->mrcCCK = AR_SREV_9300_20_OR_LATER(ah) ? true : false;
ani->ofdmsTurn = true;
ani->ofdmWeakSigDetect = true;
ani->cckNoiseImmunityLevel = ATH9K_ANI_CCK_DEF_LEVEL;
ani->ofdmNoiseImmunityLevel = ATH9K_ANI_OFDM_DEF_LEVEL;
/*
* since we expect some ongoing maintenance on the tables, let's sanity
* check here default level should not modify INI setting.
*/
ah->aniperiod = ATH9K_ANI_PERIOD;
ah->config.ani_poll_interval = ATH9K_ANI_POLLINTERVAL;
ath9k_ani_restart(ah);
ath9k_enable_mib_counters(ah);
}
