diff options
Diffstat (limited to 'drivers/net/wireless/ath/ath5k/phy.c')
| -rw-r--r-- | drivers/net/wireless/ath/ath5k/phy.c | 197 |
1 files changed, 133 insertions, 64 deletions
diff --git a/drivers/net/wireless/ath/ath5k/phy.c b/drivers/net/wireless/ath/ath5k/phy.c index 1a039f2bd732..72474c0ccaff 100644 --- a/drivers/net/wireless/ath/ath5k/phy.c +++ b/drivers/net/wireless/ath/ath5k/phy.c @@ -117,7 +117,7 @@ static unsigned int ath5k_hw_rfb_op(struct ath5k_hw *ah, /* * This code is used to optimize rf gain on different environments - * (temprature mostly) based on feedback from a power detector. + * (temperature mostly) based on feedback from a power detector. * * It's only used on RF5111 and RF5112, later RF chips seem to have * auto adjustment on hw -notice they have a much smaller BANK 7 and @@ -1124,77 +1124,148 @@ ath5k_hw_calibration_poll(struct ath5k_hw *ah) ah->ah_swi_mask = AR5K_SWI_FULL_CALIBRATION; AR5K_REG_ENABLE_BITS(ah, AR5K_CR, AR5K_CR_SWI); } +} +static int sign_extend(int val, const int nbits) +{ + int order = BIT(nbits-1); + return (val ^ order) - order; } -/** - * ath5k_hw_noise_floor_calibration - perform PHY noise floor calibration - * - * @ah: struct ath5k_hw pointer we are operating on - * @freq: the channel frequency, just used for error logging - * - * This function performs a noise floor calibration of the PHY and waits for - * it to complete. Then the noise floor value is compared to some maximum - * noise floor we consider valid. - * - * Note that this is different from what the madwifi HAL does: it reads the - * noise floor and afterwards initiates the calibration. Since the noise floor - * calibration can take some time to finish, depending on the current channel - * use, that avoids the occasional timeout warnings we are seeing now. - * - * See the following link for an Atheros patent on noise floor calibration: - * http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL \ - * &p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7245893.PN.&OS=PN/7 +static s32 ath5k_hw_read_measured_noise_floor(struct ath5k_hw *ah) +{ + s32 val; + + val = ath5k_hw_reg_read(ah, AR5K_PHY_NF); + return sign_extend(AR5K_REG_MS(val, AR5K_PHY_NF_MINCCA_PWR), 9); +} + +void ath5k_hw_init_nfcal_hist(struct ath5k_hw *ah) +{ + int i; + + ah->ah_nfcal_hist.index = 0; + for (i = 0; i < ATH5K_NF_CAL_HIST_MAX; i++) + ah->ah_nfcal_hist.nfval[i] = AR5K_TUNE_CCA_MAX_GOOD_VALUE; +} + +static void ath5k_hw_update_nfcal_hist(struct ath5k_hw *ah, s16 noise_floor) +{ + struct ath5k_nfcal_hist *hist = &ah->ah_nfcal_hist; + hist->index = (hist->index + 1) & (ATH5K_NF_CAL_HIST_MAX-1); + hist->nfval[hist->index] = noise_floor; +} + +static s16 ath5k_hw_get_median_noise_floor(struct ath5k_hw *ah) +{ + s16 sort[ATH5K_NF_CAL_HIST_MAX]; + s16 tmp; + int i, j; + + memcpy(sort, ah->ah_nfcal_hist.nfval, sizeof(sort)); + for (i = 0; i < ATH5K_NF_CAL_HIST_MAX - 1; i++) { + for (j = 1; j < ATH5K_NF_CAL_HIST_MAX - i; j++) { + if (sort[j] > sort[j-1]) { + tmp = sort[j]; + sort[j] = sort[j-1]; + sort[j-1] = tmp; + } + } + } + for (i = 0; i < ATH5K_NF_CAL_HIST_MAX; i++) { + ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE, + "cal %d:%d\n", i, sort[i]); + } + return sort[(ATH5K_NF_CAL_HIST_MAX-1) / 2]; +} + +/* + * When we tell the hardware to perform a noise floor calibration + * by setting the AR5K_PHY_AGCCTL_NF bit, it will periodically + * sample-and-hold the minimum noise level seen at the antennas. + * This value is then stored in a ring buffer of recently measured + * noise floor values so we have a moving window of the last few + * samples. * - * XXX: Since during noise floor calibration antennas are detached according to - * the patent, we should stop tx queues here. + * The median of the values in the history is then loaded into the + * hardware for its own use for RSSI and CCA measurements. */ -int -ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq) +void ath5k_hw_update_noise_floor(struct ath5k_hw *ah) { - int ret; - unsigned int i; - s32 noise_floor; + struct ath5k_eeprom_info *ee = &ah->ah_capabilities.cap_eeprom; + u32 val; + s16 nf, threshold; + u8 ee_mode; - /* - * Enable noise floor calibration - */ - AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL, - AR5K_PHY_AGCCTL_NF); + /* keep last value if calibration hasn't completed */ + if (ath5k_hw_reg_read(ah, AR5K_PHY_AGCCTL) & AR5K_PHY_AGCCTL_NF) { + ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE, + "NF did not complete in calibration window\n"); - ret = ath5k_hw_register_timeout(ah, AR5K_PHY_AGCCTL, - AR5K_PHY_AGCCTL_NF, 0, false); - if (ret) { - ATH5K_ERR(ah->ah_sc, - "noise floor calibration timeout (%uMHz)\n", freq); - return -EAGAIN; + return; } - /* Wait until the noise floor is calibrated and read the value */ - for (i = 20; i > 0; i--) { - mdelay(1); - noise_floor = ath5k_hw_reg_read(ah, AR5K_PHY_NF); - noise_floor = AR5K_PHY_NF_RVAL(noise_floor); - if (noise_floor & AR5K_PHY_NF_ACTIVE) { - noise_floor = AR5K_PHY_NF_AVAL(noise_floor); - - if (noise_floor <= AR5K_TUNE_NOISE_FLOOR) - break; - } + switch (ah->ah_current_channel->hw_value & CHANNEL_MODES) { + case CHANNEL_A: + case CHANNEL_T: + case CHANNEL_XR: + ee_mode = AR5K_EEPROM_MODE_11A; + break; + case CHANNEL_G: + case CHANNEL_TG: + ee_mode = AR5K_EEPROM_MODE_11G; + break; + default: + case CHANNEL_B: + ee_mode = AR5K_EEPROM_MODE_11B; + break; } - ATH5K_DBG_UNLIMIT(ah->ah_sc, ATH5K_DEBUG_CALIBRATE, - "noise floor %d\n", noise_floor); - if (noise_floor > AR5K_TUNE_NOISE_FLOOR) { - ATH5K_ERR(ah->ah_sc, - "noise floor calibration failed (%uMHz)\n", freq); - return -EAGAIN; + /* completed NF calibration, test threshold */ + nf = ath5k_hw_read_measured_noise_floor(ah); + threshold = ee->ee_noise_floor_thr[ee_mode]; + + if (nf > threshold) { + ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE, + "noise floor failure detected; " + "read %d, threshold %d\n", + nf, threshold); + + nf = AR5K_TUNE_CCA_MAX_GOOD_VALUE; } - ah->ah_noise_floor = noise_floor; + ath5k_hw_update_nfcal_hist(ah, nf); + nf = ath5k_hw_get_median_noise_floor(ah); - return 0; + /* load noise floor (in .5 dBm) so the hardware will use it */ + val = ath5k_hw_reg_read(ah, AR5K_PHY_NF) & ~AR5K_PHY_NF_M; + val |= (nf * 2) & AR5K_PHY_NF_M; + ath5k_hw_reg_write(ah, val, AR5K_PHY_NF); + + AR5K_REG_MASKED_BITS(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_NF, + ~(AR5K_PHY_AGCCTL_NF_EN | AR5K_PHY_AGCCTL_NF_NOUPDATE)); + + ath5k_hw_register_timeout(ah, AR5K_PHY_AGCCTL, AR5K_PHY_AGCCTL_NF, + 0, false); + + /* + * Load a high max CCA Power value (-50 dBm in .5 dBm units) + * so that we're not capped by the median we just loaded. + * This will be used as the initial value for the next noise + * floor calibration. + */ + val = (val & ~AR5K_PHY_NF_M) | ((-50 * 2) & AR5K_PHY_NF_M); + ath5k_hw_reg_write(ah, val, AR5K_PHY_NF); + AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_AGCCTL, + AR5K_PHY_AGCCTL_NF_EN | + AR5K_PHY_AGCCTL_NF_NOUPDATE | + AR5K_PHY_AGCCTL_NF); + + ah->ah_noise_floor = nf; + + ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_CALIBRATE, + "noise floor calibrated: %d\n", nf); } /* @@ -1287,7 +1358,7 @@ static int ath5k_hw_rf5110_calibrate(struct ath5k_hw *ah, return ret; } - ath5k_hw_noise_floor_calibration(ah, channel->center_freq); + ath5k_hw_update_noise_floor(ah); /* * Re-enable RX/TX and beacons @@ -1328,7 +1399,7 @@ static int ath5k_hw_rf511x_calibrate(struct ath5k_hw *ah, if (i_coffd == 0 || q_coffd == 0) goto done; - i_coff = ((-iq_corr) / i_coffd) & 0x3f; + i_coff = ((-iq_corr) / i_coffd); /* Boundary check */ if (i_coff > 31) @@ -1336,7 +1407,7 @@ static int ath5k_hw_rf511x_calibrate(struct ath5k_hw *ah, if (i_coff < -32) i_coff = -32; - q_coff = (((s32)i_pwr / q_coffd) - 128) & 0x1f; + q_coff = (((s32)i_pwr / q_coffd) - 128); /* Boundary check */ if (q_coff > 15) @@ -1360,7 +1431,7 @@ done: * since noise floor calibration interrupts rx path while I/Q * calibration doesn't. We don't need to run noise floor calibration * as often as I/Q calibration.*/ - ath5k_hw_noise_floor_calibration(ah, channel->center_freq); + ath5k_hw_update_noise_floor(ah); /* Initiate a gain_F calibration */ ath5k_hw_request_rfgain_probe(ah); @@ -2675,7 +2746,7 @@ ath5k_setup_channel_powertable(struct ath5k_hw *ah, /* Fill curves in reverse order * from lower power (max gain) * to higher power. Use curve -> idx - * backmaping we did on eeprom init */ + * backmapping we did on eeprom init */ u8 idx = pdg_curve_to_idx[pdg]; /* Grab the needed curves by index */ @@ -2777,7 +2848,7 @@ ath5k_setup_channel_powertable(struct ath5k_hw *ah, /* Now we have a set of curves for this * channel on tmpL (x range is table_max - table_min * and y values are tmpL[pdg][]) sorted in the same - * order as EEPROM (because we've used the backmaping). + * order as EEPROM (because we've used the backmapping). * So for RF5112 it's from higher power to lower power * and for RF2413 it's from lower power to higher power. * For RF5111 we only have one curve. */ @@ -2954,8 +3025,6 @@ ath5k_hw_txpower(struct ath5k_hw *ah, struct ieee80211_channel *channel, ATH5K_ERR(ah->ah_sc, "invalid tx power: %u\n", txpower); return -EINVAL; } - if (txpower == 0) - txpower = AR5K_TUNE_DEFAULT_TXPOWER; /* Reset TX power values */ memset(&ah->ah_txpower, 0, sizeof(ah->ah_txpower)); |