From 6f255425ac3b10c3352c926e7b53e5ea1c364ca4 Mon Sep 17 00:00:00 2001 From: "Luis R. Rodriguez" Date: Fri, 3 Oct 2008 15:45:27 -0700 Subject: ath9k: enable ANI to help with noisy environments This enables Adaptive Noise Immunity (ANI) on ath9k. ANI is as algorithm designed to minimize the detrimental effects of time-varying interferences. This should help with throughput in noisy environments. To use ANI we re-enable the MIB interrupt. Since ANI works on a timer and updates the noise floor we take advantage of this and also report a non-static noise floor now to mac80211. Signed-off-by: Sujith Manoharan Signed-off-by: Jouni Malinen Signed-off-by: Luis R. Rodriguez Signed-off-by: John W. Linville --- drivers/net/wireless/ath9k/ath9k.h | 2 +- drivers/net/wireless/ath9k/core.c | 129 +++++++++++++++++++++++++++++++++++-- drivers/net/wireless/ath9k/core.h | 25 +++++++ drivers/net/wireless/ath9k/hw.c | 35 ++++++++-- drivers/net/wireless/ath9k/main.c | 18 +++++- drivers/net/wireless/ath9k/recv.c | 13 +--- 6 files changed, 197 insertions(+), 25 deletions(-) (limited to 'drivers/net/wireless/ath9k') diff --git a/drivers/net/wireless/ath9k/ath9k.h b/drivers/net/wireless/ath9k/ath9k.h index 0e897c27685..accace5f7ef 100644 --- a/drivers/net/wireless/ath9k/ath9k.h +++ b/drivers/net/wireless/ath9k/ath9k.h @@ -854,7 +854,7 @@ bool ath9k_hw_calibrate(struct ath_hal *ah, u8 rxchainmask, bool longcal, bool *isCalDone); -int16_t ath9k_hw_getchan_noise(struct ath_hal *ah, +s16 ath9k_hw_getchan_noise(struct ath_hal *ah, struct ath9k_channel *chan); void ath9k_hw_write_associd(struct ath_hal *ah, const u8 *bssid, u16 assocId); diff --git a/drivers/net/wireless/ath9k/core.c b/drivers/net/wireless/ath9k/core.c index 5af7dfbd423..c5033f6f42a 100644 --- a/drivers/net/wireless/ath9k/core.c +++ b/drivers/net/wireless/ath9k/core.c @@ -490,6 +490,122 @@ void ath_update_chainmask(struct ath_softc *sc, int is_ht) __func__, sc->sc_tx_chainmask, sc->sc_rx_chainmask); } +/*******/ +/* ANI */ +/*******/ + +/* + * This routine performs the periodic noise floor calibration function + * that is used to adjust and optimize the chip performance. This + * takes environmental changes (location, temperature) into account. + * When the task is complete, it reschedules itself depending on the + * appropriate interval that was calculated. + */ + +static void ath_ani_calibrate(unsigned long data) +{ + struct ath_softc *sc; + struct ath_hal *ah; + bool longcal = false; + bool shortcal = false; + bool aniflag = false; + unsigned int timestamp = jiffies_to_msecs(jiffies); + u32 cal_interval; + + sc = (struct ath_softc *)data; + ah = sc->sc_ah; + + /* + * don't calibrate when we're scanning. + * we are most likely not on our home channel. + */ + if (sc->rx_filter & FIF_BCN_PRBRESP_PROMISC) + return; + + /* Long calibration runs independently of short calibration. */ + if ((timestamp - sc->sc_ani.sc_longcal_timer) >= ATH_LONG_CALINTERVAL) { + longcal = true; + DPRINTF(sc, ATH_DBG_ANI, "%s: longcal @%lu\n", + __func__, jiffies); + sc->sc_ani.sc_longcal_timer = timestamp; + } + + /* Short calibration applies only while sc_caldone is false */ + if (!sc->sc_ani.sc_caldone) { + if ((timestamp - sc->sc_ani.sc_shortcal_timer) >= + ATH_SHORT_CALINTERVAL) { + shortcal = true; + DPRINTF(sc, ATH_DBG_ANI, "%s: shortcal @%lu\n", + __func__, jiffies); + sc->sc_ani.sc_shortcal_timer = timestamp; + sc->sc_ani.sc_resetcal_timer = timestamp; + } + } else { + if ((timestamp - sc->sc_ani.sc_resetcal_timer) >= + ATH_RESTART_CALINTERVAL) { + ath9k_hw_reset_calvalid(ah, ah->ah_curchan, + &sc->sc_ani.sc_caldone); + if (sc->sc_ani.sc_caldone) + sc->sc_ani.sc_resetcal_timer = timestamp; + } + } + + /* Verify whether we must check ANI */ + if ((timestamp - sc->sc_ani.sc_checkani_timer) >= + ATH_ANI_POLLINTERVAL) { + aniflag = true; + sc->sc_ani.sc_checkani_timer = timestamp; + } + + /* Skip all processing if there's nothing to do. */ + if (longcal || shortcal || aniflag) { + /* Call ANI routine if necessary */ + if (aniflag) + ath9k_hw_ani_monitor(ah, &sc->sc_halstats, + ah->ah_curchan); + + /* Perform calibration if necessary */ + if (longcal || shortcal) { + bool iscaldone = false; + + if (ath9k_hw_calibrate(ah, ah->ah_curchan, + sc->sc_rx_chainmask, longcal, + &iscaldone)) { + if (longcal) + sc->sc_ani.sc_noise_floor = + ath9k_hw_getchan_noise(ah, + ah->ah_curchan); + + DPRINTF(sc, ATH_DBG_ANI, + "%s: calibrate chan %u/%x nf: %d\n", + __func__, + ah->ah_curchan->channel, + ah->ah_curchan->channelFlags, + sc->sc_ani.sc_noise_floor); + } else { + DPRINTF(sc, ATH_DBG_ANY, + "%s: calibrate chan %u/%x failed\n", + __func__, + ah->ah_curchan->channel, + ah->ah_curchan->channelFlags); + } + sc->sc_ani.sc_caldone = iscaldone; + } + } + + /* + * Set timer interval based on previous results. + * The interval must be the shortest necessary to satisfy ANI, + * short calibration and long calibration. + */ + + cal_interval = ATH_ANI_POLLINTERVAL; + if (!sc->sc_ani.sc_caldone) + cal_interval = min(cal_interval, (u32)ATH_SHORT_CALINTERVAL); + + mod_timer(&sc->sc_ani.timer, jiffies + msecs_to_jiffies(cal_interval)); +} + /******************/ /* VAP management */ /******************/ @@ -676,12 +792,6 @@ int ath_open(struct ath_softc *sc, struct ath9k_channel *initial_chan) if (ah->ah_caps.hw_caps & ATH9K_HW_CAP_HT) sc->sc_imask |= ATH9K_INT_CST; - /* Note: We disable MIB interrupts for now as we don't yet - * handle processing ANI, otherwise you will get an interrupt - * storm after about 7 hours of usage making the system unusable - * with huge latency. Once we do have ANI processing included - * we can re-enable this interrupt. */ -#if 0 /* * Enable MIB interrupts when there are hardware phy counters. * Note we only do this (at the moment) for station mode. @@ -690,7 +800,6 @@ int ath_open(struct ath_softc *sc, struct ath9k_channel *initial_chan) ((sc->sc_ah->ah_opmode == ATH9K_M_STA) || (sc->sc_ah->ah_opmode == ATH9K_M_IBSS))) sc->sc_imask |= ATH9K_INT_MIB; -#endif /* * Some hardware processes the TIM IE and fires an * interrupt when the TIM bit is set. For hardware @@ -991,6 +1100,10 @@ int ath_init(u16 devid, struct ath_softc *sc) } sc->sc_ah = ah; + /* Initializes the noise floor to a reasonable default value. + * Later on this will be updated during ANI processing. */ + sc->sc_ani.sc_noise_floor = ATH_DEFAULT_NOISE_FLOOR; + /* Get the hardware key cache size. */ sc->sc_keymax = ah->ah_caps.keycache_size; if (sc->sc_keymax > ATH_KEYMAX) { @@ -1098,6 +1211,8 @@ int ath_init(u16 devid, struct ath_softc *sc) goto bad2; } + setup_timer(&sc->sc_ani.timer, ath_ani_calibrate, (unsigned long)sc); + sc->sc_rc = ath_rate_attach(ah); if (sc->sc_rc == NULL) { error = -EIO; diff --git a/drivers/net/wireless/ath9k/core.h b/drivers/net/wireless/ath9k/core.h index 5b4f1c48a61..cb3e61e57c4 100644 --- a/drivers/net/wireless/ath9k/core.h +++ b/drivers/net/wireless/ath9k/core.h @@ -800,6 +800,28 @@ void ath_slow_ant_div(struct ath_antdiv *antdiv, struct ath_rx_status *rx_stats); void ath_setdefantenna(void *sc, u32 antenna); +/*******/ +/* ANI */ +/*******/ + +/* ANI values for STA only. + FIXME: Add appropriate values for AP later */ + +#define ATH_ANI_POLLINTERVAL 100 /* 100 milliseconds between ANI poll */ +#define ATH_SHORT_CALINTERVAL 1000 /* 1 second between calibrations */ +#define ATH_LONG_CALINTERVAL 30000 /* 30 seconds between calibrations */ +#define ATH_RESTART_CALINTERVAL 1200000 /* 20 minutes between calibrations */ + +struct ath_ani { + bool sc_caldone; + int16_t sc_noise_floor; + unsigned int sc_longcal_timer; + unsigned int sc_shortcal_timer; + unsigned int sc_resetcal_timer; + unsigned int sc_checkani_timer; + struct timer_list timer; +}; + /********************/ /* LED Control */ /********************/ @@ -1028,6 +1050,9 @@ struct ath_softc { /* Rfkill */ struct ath_rfkill rf_kill; + + /* ANI */ + struct ath_ani sc_ani; }; int ath_init(u16 devid, struct ath_softc *sc); diff --git a/drivers/net/wireless/ath9k/hw.c b/drivers/net/wireless/ath9k/hw.c index 272c7581660..62e44a0ef99 100644 --- a/drivers/net/wireless/ath9k/hw.c +++ b/drivers/net/wireless/ath9k/hw.c @@ -329,7 +329,7 @@ static void ath9k_hw_set_defaults(struct ath_hal *ah) ah->ah_config.ofdm_trig_high = 500; ah->ah_config.cck_trig_high = 200; ah->ah_config.cck_trig_low = 100; - ah->ah_config.enable_ani = 0; + ah->ah_config.enable_ani = 1; ah->ah_config.noise_immunity_level = 4; ah->ah_config.ofdm_weaksignal_det = 1; ah->ah_config.cck_weaksignal_thr = 0; @@ -8405,23 +8405,48 @@ u32 ath9k_hw_mhz2ieee(struct ath_hal *ah, u32 freq, u32 flags) } } -int16_t +/* 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_hal *ah, s16 nf) +{ + if (nf > ATH9K_NF_TOO_LOW) { + DPRINTF(ah->ah_sc, ATH_DBG_NF_CAL, + "%s: noise floor value detected (%d) is " + "lower than what we think is a " + "reasonable value (%d)\n", + __func__, nf, ATH9K_NF_TOO_LOW); + return false; + } + return true; +} + +s16 ath9k_hw_getchan_noise(struct ath_hal *ah, struct ath9k_channel *chan) { struct ath9k_channel *ichan; + s16 nf; ichan = ath9k_regd_check_channel(ah, chan); if (ichan == NULL) { DPRINTF(ah->ah_sc, ATH_DBG_NF_CAL, "%s: invalid channel %u/0x%x; no mapping\n", __func__, chan->channel, chan->channelFlags); - return 0; + return ATH_DEFAULT_NOISE_FLOOR; } if (ichan->rawNoiseFloor == 0) { enum wireless_mode mode = ath9k_hw_chan2wmode(ah, chan); - return NOISE_FLOOR[mode]; + nf = NOISE_FLOOR[mode]; } else - return ichan->rawNoiseFloor; + nf = ichan->rawNoiseFloor; + + if (!ath9k_hw_nf_in_range(ah, nf)) + nf = ATH_DEFAULT_NOISE_FLOOR; + + return nf; } bool ath9k_hw_set_tsfadjust(struct ath_hal *ah, u32 setting) diff --git a/drivers/net/wireless/ath9k/main.c b/drivers/net/wireless/ath9k/main.c index 2caba440316..74726990d59 100644 --- a/drivers/net/wireless/ath9k/main.c +++ b/drivers/net/wireless/ath9k/main.c @@ -274,10 +274,12 @@ static void ath9k_rx_prepare(struct ath_softc *sc, rx_status->mactime = status->tsf; rx_status->band = curchan->band; rx_status->freq = curchan->center_freq; - rx_status->noise = ATH_DEFAULT_NOISE_FLOOR; + rx_status->noise = sc->sc_ani.sc_noise_floor; rx_status->signal = rx_status->noise + status->rssi; rx_status->rate_idx = ath_rate2idx(sc, (status->rateKbps / 100)); rx_status->antenna = status->antenna; + + /* XXX Fix me, 64 cannot be the max rssi value, rigure it out */ rx_status->qual = status->rssi * 100 / 64; if (status->flags & ATH_RX_MIC_ERROR) @@ -427,6 +429,11 @@ static void ath9k_bss_assoc_info(struct ath_softc *sc, ath_rate_newstate(sc, avp); /* Update ratectrl about the new state */ ath_rc_node_update(hw, avp->rc_node); + + /* Start ANI */ + mod_timer(&sc->sc_ani.timer, + jiffies + msecs_to_jiffies(ATH_ANI_POLLINTERVAL)); + } else { DPRINTF(sc, ATH_DBG_CONFIG, "%s: Bss Info DISSOC\n", __func__); @@ -1173,6 +1180,13 @@ static int ath9k_add_interface(struct ieee80211_hw *hw, return error; } + if (conf->type == NL80211_IFTYPE_AP) { + /* TODO: is this a suitable place to start ANI for AP mode? */ + /* Start ANI */ + mod_timer(&sc->sc_ani.timer, + jiffies + msecs_to_jiffies(ATH_ANI_POLLINTERVAL)); + } + return 0; } @@ -1195,6 +1209,8 @@ static void ath9k_remove_interface(struct ieee80211_hw *hw, #ifdef CONFIG_SLOW_ANT_DIV ath_slow_ant_div_stop(&sc->sc_antdiv); #endif + /* Stop ANI */ + del_timer_sync(&sc->sc_ani.timer); /* Update ratectrl */ ath_rate_newstate(sc, avp); diff --git a/drivers/net/wireless/ath9k/recv.c b/drivers/net/wireless/ath9k/recv.c index f4be5d11c9d..4983402af55 100644 --- a/drivers/net/wireless/ath9k/recv.c +++ b/drivers/net/wireless/ath9k/recv.c @@ -999,20 +999,11 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush) rx_status.flags |= ATH_RX_SHORT_GI; } - /* sc->sc_noise_floor is only available when the station + /* sc_noise_floor is only available when the station attaches to an AP, so we use a default value if we are not yet attached. */ - - /* XXX we should use either sc->sc_noise_floor or - * ath_hal_getChanNoise(ah, &sc->sc_curchan) - * to calculate the noise floor. - * However, the value returned by ath_hal_getChanNoise - * seems to be incorrect (-31dBm on the last test), - * so we will use a hard-coded value until we - * figure out what is going on. - */ rx_status.abs_rssi = - ds->ds_rxstat.rs_rssi + ATH_DEFAULT_NOISE_FLOOR; + ds->ds_rxstat.rs_rssi + sc->sc_ani.sc_noise_floor; pci_dma_sync_single_for_cpu(sc->pdev, bf->bf_buf_addr, -- cgit v1.2.3