From 8da58553cc63f6e9afcab0db033c79e554334c13 Mon Sep 17 00:00:00 2001 From: Wojciech Dubowik Date: Wed, 24 Jan 2018 09:02:18 +0100 Subject: [PATCH] ath9k: Use calibrated noise floor value when available AR9003 series allows to calibrate noise floor for different frequency bins. Once it's done it's possible to get more accurate rssi/signal values over whole frequency band at a given temperature. The RSSI/signal accuracy reported by calibrated RF cards improves from 6 to up to 2dB. This could be interesting for application which require good signal accuracy like roaming or mesh protocols. Signed-off-by: Wojciech Dubowik Signed-off-by: Kalle Valo --- drivers/net/wireless/ath/ath9k/calib.c | 38 +++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 14 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c index 13ab6bc..3d9447e 100644 --- a/drivers/net/wireless/ath/ath9k/calib.c +++ b/drivers/net/wireless/ath/ath9k/calib.c @@ -58,19 +58,25 @@ static struct ath_nf_limits *ath9k_hw_get_nf_limits(struct ath_hw *ah, } static s16 ath9k_hw_get_default_nf(struct ath_hw *ah, - struct ath9k_channel *chan) + struct ath9k_channel *chan, + int chain) { - return ath9k_hw_get_nf_limits(ah, chan)->nominal; + s16 calib_nf = ath9k_hw_get_nf_limits(ah, chan)->cal[chain]; + + if (calib_nf) + return calib_nf; + else + return ath9k_hw_get_nf_limits(ah, chan)->nominal; } s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan, s16 nf) { - s8 noise = ATH_DEFAULT_NOISE_FLOOR; + s8 noise = ath9k_hw_get_default_nf(ah, chan, 0); if (nf) { s8 delta = nf - ATH9K_NF_CAL_NOISE_THRESH - - ath9k_hw_get_default_nf(ah, chan); + ath9k_hw_get_default_nf(ah, chan, 0); if (delta > 0) noise += delta; } @@ -240,7 +246,7 @@ int ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan) unsigned i, j; u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask; struct ath_common *common = ath9k_hw_common(ah); - s16 default_nf = ath9k_hw_get_default_nf(ah, chan); + s16 default_nf = ath9k_hw_get_nf_limits(ah, chan)->nominal; u32 bb_agc_ctl = REG_READ(ah, AR_PHY_AGC_CONTROL); if (ah->caldata) @@ -258,8 +264,13 @@ int ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan) nfval = ah->nf_override; else if (h) nfval = h[i].privNF; - else - nfval = default_nf; + else { + /* Try to get calibrated noise floor value */ + nfval = + ath9k_hw_get_nf_limits(ah, chan)->cal[i]; + if (nfval > -60 || nfval < -127) + nfval = default_nf; + } REG_RMW(ah, ah->nf_regs[i], (((u32) nfval << 1) & 0x1ff), 0x1ff); @@ -429,20 +440,19 @@ 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; + int i, j, k = 0; ah->caldata->channel = chan->channel; ah->caldata->channelFlags = chan->channelFlags; 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].privNF = ath9k_hw_get_default_nf(ah, chan, k); h[i].invalidNFcount = AR_PHY_CCA_FILTERWINDOW_LENGTH; - for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++) { - h[i].nfCalBuffer[j] = default_nf; - } + for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++) + h[i].nfCalBuffer[j] = h[i].privNF; + if (++k >= AR5416_MAX_CHAINS) + k = 0; } } -- 2.7.4