diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-calib.c')
-rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-calib.c | 778 |
1 files changed, 778 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-calib.c b/drivers/net/wireless/iwlwifi/iwl-calib.c new file mode 100644 index 00000000000..16213b05ed9 --- /dev/null +++ b/drivers/net/wireless/iwlwifi/iwl-calib.c @@ -0,0 +1,778 @@ +/****************************************************************************** + * + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2008 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, + * USA + * + * The full GNU General Public License is included in this distribution + * in the file called LICENSE.GPL. + * + * Contact Information: + * Tomas Winkler <tomas.winkler@intel.com> + * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 + * + * BSD LICENSE + * + * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + *****************************************************************************/ + +#include <linux/kernel.h> +#include <net/mac80211.h> + +#include "iwl-4965.h" +#include "iwl-core.h" +#include "iwl-calib.h" +#include "iwl-eeprom.h" + +/* "false alarms" are signals that our DSP tries to lock onto, + * but then determines that they are either noise, or transmissions + * from a distant wireless network (also "noise", really) that get + * "stepped on" by stronger transmissions within our own network. + * This algorithm attempts to set a sensitivity level that is high + * enough to receive all of our own network traffic, but not so + * high that our DSP gets too busy trying to lock onto non-network + * activity/noise. */ +static int iwl_sens_energy_cck(struct iwl_priv *priv, + u32 norm_fa, + u32 rx_enable_time, + struct statistics_general_data *rx_info) +{ + u32 max_nrg_cck = 0; + int i = 0; + u8 max_silence_rssi = 0; + u32 silence_ref = 0; + u8 silence_rssi_a = 0; + u8 silence_rssi_b = 0; + u8 silence_rssi_c = 0; + u32 val; + + /* "false_alarms" values below are cross-multiplications to assess the + * numbers of false alarms within the measured period of actual Rx + * (Rx is off when we're txing), vs the min/max expected false alarms + * (some should be expected if rx is sensitive enough) in a + * hypothetical listening period of 200 time units (TU), 204.8 msec: + * + * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time + * + * */ + u32 false_alarms = norm_fa * 200 * 1024; + u32 max_false_alarms = MAX_FA_CCK * rx_enable_time; + u32 min_false_alarms = MIN_FA_CCK * rx_enable_time; + struct iwl_sensitivity_data *data = NULL; + const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens; + + data = &(priv->sensitivity_data); + + data->nrg_auto_corr_silence_diff = 0; + + /* Find max silence rssi among all 3 receivers. + * This is background noise, which may include transmissions from other + * networks, measured during silence before our network's beacon */ + silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a & + ALL_BAND_FILTER) >> 8); + silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b & + ALL_BAND_FILTER) >> 8); + silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c & + ALL_BAND_FILTER) >> 8); + + val = max(silence_rssi_b, silence_rssi_c); + max_silence_rssi = max(silence_rssi_a, (u8) val); + + /* Store silence rssi in 20-beacon history table */ + data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi; + data->nrg_silence_idx++; + if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L) + data->nrg_silence_idx = 0; + + /* Find max silence rssi across 20 beacon history */ + for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) { + val = data->nrg_silence_rssi[i]; + silence_ref = max(silence_ref, val); + } + IWL_DEBUG_CALIB("silence a %u, b %u, c %u, 20-bcn max %u\n", + silence_rssi_a, silence_rssi_b, silence_rssi_c, + silence_ref); + + /* Find max rx energy (min value!) among all 3 receivers, + * measured during beacon frame. + * Save it in 10-beacon history table. */ + i = data->nrg_energy_idx; + val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c); + data->nrg_value[i] = min(rx_info->beacon_energy_a, val); + + data->nrg_energy_idx++; + if (data->nrg_energy_idx >= 10) + data->nrg_energy_idx = 0; + + /* Find min rx energy (max value) across 10 beacon history. + * This is the minimum signal level that we want to receive well. + * Add backoff (margin so we don't miss slightly lower energy frames). + * This establishes an upper bound (min value) for energy threshold. */ + max_nrg_cck = data->nrg_value[0]; + for (i = 1; i < 10; i++) + max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i])); + max_nrg_cck += 6; + + IWL_DEBUG_CALIB("rx energy a %u, b %u, c %u, 10-bcn max/min %u\n", + rx_info->beacon_energy_a, rx_info->beacon_energy_b, + rx_info->beacon_energy_c, max_nrg_cck - 6); + + /* Count number of consecutive beacons with fewer-than-desired + * false alarms. */ + if (false_alarms < min_false_alarms) + data->num_in_cck_no_fa++; + else + data->num_in_cck_no_fa = 0; + IWL_DEBUG_CALIB("consecutive bcns with few false alarms = %u\n", + data->num_in_cck_no_fa); + + /* If we got too many false alarms this time, reduce sensitivity */ + if ((false_alarms > max_false_alarms) && + (data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) { + IWL_DEBUG_CALIB("norm FA %u > max FA %u\n", + false_alarms, max_false_alarms); + IWL_DEBUG_CALIB("... reducing sensitivity\n"); + data->nrg_curr_state = IWL_FA_TOO_MANY; + /* Store for "fewer than desired" on later beacon */ + data->nrg_silence_ref = silence_ref; + + /* increase energy threshold (reduce nrg value) + * to decrease sensitivity */ + if (data->nrg_th_cck > + (ranges->max_nrg_cck + NRG_STEP_CCK)) + data->nrg_th_cck = data->nrg_th_cck + - NRG_STEP_CCK; + else + data->nrg_th_cck = ranges->max_nrg_cck; + /* Else if we got fewer than desired, increase sensitivity */ + } else if (false_alarms < min_false_alarms) { + data->nrg_curr_state = IWL_FA_TOO_FEW; + + /* Compare silence level with silence level for most recent + * healthy number or too many false alarms */ + data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref - + (s32)silence_ref; + + IWL_DEBUG_CALIB("norm FA %u < min FA %u, silence diff %d\n", + false_alarms, min_false_alarms, + data->nrg_auto_corr_silence_diff); + + /* Increase value to increase sensitivity, but only if: + * 1a) previous beacon did *not* have *too many* false alarms + * 1b) AND there's a significant difference in Rx levels + * from a previous beacon with too many, or healthy # FAs + * OR 2) We've seen a lot of beacons (100) with too few + * false alarms */ + if ((data->nrg_prev_state != IWL_FA_TOO_MANY) && + ((data->nrg_auto_corr_silence_diff > NRG_DIFF) || + (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) { + + IWL_DEBUG_CALIB("... increasing sensitivity\n"); + /* Increase nrg value to increase sensitivity */ + val = data->nrg_th_cck + NRG_STEP_CCK; + data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val); + } else { + IWL_DEBUG_CALIB("... but not changing sensitivity\n"); + } + + /* Else we got a healthy number of false alarms, keep status quo */ + } else { + IWL_DEBUG_CALIB(" FA in safe zone\n"); + data->nrg_curr_state = IWL_FA_GOOD_RANGE; + + /* Store for use in "fewer than desired" with later beacon */ + data->nrg_silence_ref = silence_ref; + + /* If previous beacon had too many false alarms, + * give it some extra margin by reducing sensitivity again + * (but don't go below measured energy of desired Rx) */ + if (IWL_FA_TOO_MANY == data->nrg_prev_state) { + IWL_DEBUG_CALIB("... increasing margin\n"); + if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN)) + data->nrg_th_cck -= NRG_MARGIN; + else + data->nrg_th_cck = max_nrg_cck; + } + } + + /* Make sure the energy threshold does not go above the measured + * energy of the desired Rx signals (reduced by backoff margin), + * or else we might start missing Rx frames. + * Lower value is higher energy, so we use max()! + */ + data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck); + IWL_DEBUG_CALIB("new nrg_th_cck %u\n", data->nrg_th_cck); + + data->nrg_prev_state = data->nrg_curr_state; + + /* Auto-correlation CCK algorithm */ + if (false_alarms > min_false_alarms) { + + /* increase auto_corr values to decrease sensitivity + * so the DSP won't be disturbed by the noise + */ + if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK) + data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1; + else { + val = data->auto_corr_cck + AUTO_CORR_STEP_CCK; + data->auto_corr_cck = + min((u32)ranges->auto_corr_max_cck, val); + } + val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK; + data->auto_corr_cck_mrc = + min((u32)ranges->auto_corr_max_cck_mrc, val); + } else if ((false_alarms < min_false_alarms) && + ((data->nrg_auto_corr_silence_diff > NRG_DIFF) || + (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) { + + /* Decrease auto_corr values to increase sensitivity */ + val = data->auto_corr_cck - AUTO_CORR_STEP_CCK; + data->auto_corr_cck = + max((u32)ranges->auto_corr_min_cck, val); + val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK; + data->auto_corr_cck_mrc = + max((u32)ranges->auto_corr_min_cck_mrc, val); + } + + return 0; +} + + +static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv, + u32 norm_fa, + u32 rx_enable_time) +{ + u32 val; + u32 false_alarms = norm_fa * 200 * 1024; + u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time; + u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time; + struct iwl_sensitivity_data *data = NULL; + const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens; + + data = &(priv->sensitivity_data); + + /* If we got too many false alarms this time, reduce sensitivity */ + if (false_alarms > max_false_alarms) { + + IWL_DEBUG_CALIB("norm FA %u > max FA %u)\n", + false_alarms, max_false_alarms); + + val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm = + min((u32)ranges->auto_corr_max_ofdm, val); + + val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm_mrc = + min((u32)ranges->auto_corr_max_ofdm_mrc, val); + + val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm_x1 = + min((u32)ranges->auto_corr_max_ofdm_x1, val); + + val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm_mrc_x1 = + min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val); + } + + /* Else if we got fewer than desired, increase sensitivity */ + else if (false_alarms < min_false_alarms) { + + IWL_DEBUG_CALIB("norm FA %u < min FA %u\n", + false_alarms, min_false_alarms); + + val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm = + max((u32)ranges->auto_corr_min_ofdm, val); + + val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm_mrc = + max((u32)ranges->auto_corr_min_ofdm_mrc, val); + + val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm_x1 = + max((u32)ranges->auto_corr_min_ofdm_x1, val); + + val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM; + data->auto_corr_ofdm_mrc_x1 = + max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val); + } else { + IWL_DEBUG_CALIB("min FA %u < norm FA %u < max FA %u OK\n", + min_false_alarms, false_alarms, max_false_alarms); + } + return 0; +} + +/* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */ +static int iwl_sensitivity_write(struct iwl_priv *priv) +{ + int ret = 0; + struct iwl_sensitivity_cmd cmd ; + struct iwl_sensitivity_data *data = NULL; + struct iwl_host_cmd cmd_out = { + .id = SENSITIVITY_CMD, + .len = sizeof(struct iwl_sensitivity_cmd), + .meta.flags = CMD_ASYNC, + .data = &cmd, + }; + + data = &(priv->sensitivity_data); + + memset(&cmd, 0, sizeof(cmd)); + + cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] = + cpu_to_le16((u16)data->auto_corr_ofdm); + cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] = + cpu_to_le16((u16)data->auto_corr_ofdm_mrc); + cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] = + cpu_to_le16((u16)data->auto_corr_ofdm_x1); + cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] = + cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1); + + cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] = + cpu_to_le16((u16)data->auto_corr_cck); + cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] = + cpu_to_le16((u16)data->auto_corr_cck_mrc); + + cmd.table[HD_MIN_ENERGY_CCK_DET_INDEX] = + cpu_to_le16((u16)data->nrg_th_cck); + cmd.table[HD_MIN_ENERGY_OFDM_DET_INDEX] = + cpu_to_le16((u16)data->nrg_th_ofdm); + + cmd.table[HD_BARKER_CORR_TH_ADD_MIN_INDEX] = + __constant_cpu_to_le16(190); + cmd.table[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] = + __constant_cpu_to_le16(390); + cmd.table[HD_OFDM_ENERGY_TH_IN_INDEX] = + __constant_cpu_to_le16(62); + + IWL_DEBUG_CALIB("ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n", + data->auto_corr_ofdm, data->auto_corr_ofdm_mrc, + data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1, + data->nrg_th_ofdm); + + IWL_DEBUG_CALIB("cck: ac %u mrc %u thresh %u\n", + data->auto_corr_cck, data->auto_corr_cck_mrc, + data->nrg_th_cck); + + /* Update uCode's "work" table, and copy it to DSP */ + cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE; + + /* Don't send command to uCode if nothing has changed */ + if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]), + sizeof(u16)*HD_TABLE_SIZE)) { + IWL_DEBUG_CALIB("No change in SENSITIVITY_CMD\n"); + return 0; + } + + /* Copy table for comparison next time */ + memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]), + sizeof(u16)*HD_TABLE_SIZE); + + ret = iwl_send_cmd(priv, &cmd_out); + if (ret) + IWL_ERROR("SENSITIVITY_CMD failed\n"); + + return ret; +} + +void iwl_init_sensitivity(struct iwl_priv *priv) +{ + int ret = 0; + int i; + struct iwl_sensitivity_data *data = NULL; + const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens; + + IWL_DEBUG_CALIB("Start iwl_init_sensitivity\n"); + + /* Clear driver's sensitivity algo data */ + data = &(priv->sensitivity_data); + + if (ranges == NULL) + /* can happen if IWLWIFI_RUN_TIME_CALIB is selected + * but no IWLXXXX_RUN_TIME_CALIB for specific is selected */ + return; + + memset(data, 0, sizeof(struct iwl_sensitivity_data)); + + data->num_in_cck_no_fa = 0; + data->nrg_curr_state = IWL_FA_TOO_MANY; + data->nrg_prev_state = IWL_FA_TOO_MANY; + data->nrg_silence_ref = 0; + data->nrg_silence_idx = 0; + data->nrg_energy_idx = 0; + + for (i = 0; i < 10; i++) + data->nrg_value[i] = 0; + + for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) + data->nrg_silence_rssi[i] = 0; + + data->auto_corr_ofdm = 90; + data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc; + data->auto_corr_ofdm_x1 = ranges->auto_corr_min_ofdm_x1; + data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1; + data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF; + data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc; + data->nrg_th_cck = ranges->nrg_th_cck; + data->nrg_th_ofdm = ranges->nrg_th_ofdm; + + data->last_bad_plcp_cnt_ofdm = 0; + data->last_fa_cnt_ofdm = 0; + data->last_bad_plcp_cnt_cck = 0; + data->last_fa_cnt_cck = 0; + + ret |= iwl_sensitivity_write(priv); + IWL_DEBUG_CALIB("<<return 0x%X\n", ret); +} +EXPORT_SYMBOL(iwl_init_sensitivity); + +void iwl_sensitivity_calibration(struct iwl_priv *priv, + struct iwl4965_notif_statistics *resp) +{ + u32 rx_enable_time; + u32 fa_cck; + u32 fa_ofdm; + u32 bad_plcp_cck; + u32 bad_plcp_ofdm; + u32 norm_fa_ofdm; + u32 norm_fa_cck; + struct iwl_sensitivity_data *data = NULL; + struct statistics_rx_non_phy *rx_info = &(resp->rx.general); + struct statistics_rx *statistics = &(resp->rx); + unsigned long flags; + struct statistics_general_data statis; + + data = &(priv->sensitivity_data); + + if (!iwl_is_associated(priv)) { + IWL_DEBUG_CALIB("<< - not associated\n"); + return; + } + + spin_lock_irqsave(&priv->lock, flags); + if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) { + IWL_DEBUG_CALIB("<< invalid data.\n"); + spin_unlock_irqrestore(&priv->lock, flags); + return; + } + + /* Extract Statistics: */ + rx_enable_time = le32_to_cpu(rx_info->channel_load); + fa_cck = le32_to_cpu(statistics->cck.false_alarm_cnt); + fa_ofdm = le32_to_cpu(statistics->ofdm.false_alarm_cnt); + bad_plcp_cck = le32_to_cpu(statistics->cck.plcp_err); + bad_plcp_ofdm = le32_to_cpu(statistics->ofdm.plcp_err); + + statis.beacon_silence_rssi_a = + le32_to_cpu(statistics->general.beacon_silence_rssi_a); + statis.beacon_silence_rssi_b = + le32_to_cpu(statistics->general.beacon_silence_rssi_b); + statis.beacon_silence_rssi_c = + le32_to_cpu(statistics->general.beacon_silence_rssi_c); + statis.beacon_energy_a = + le32_to_cpu(statistics->general.beacon_energy_a); + statis.beacon_energy_b = + le32_to_cpu(statistics->general.beacon_energy_b); + statis.beacon_energy_c = + le32_to_cpu(statistics->general.beacon_energy_c); + + spin_unlock_irqrestore(&priv->lock, flags); + + IWL_DEBUG_CALIB("rx_enable_time = %u usecs\n", rx_enable_time); + + if (!rx_enable_time) { + IWL_DEBUG_CALIB("<< RX Enable Time == 0! \n"); + return; + } + + /* These statistics increase monotonically, and do not reset + * at each beacon. Calculate difference from last value, or just + * use the new statistics value if it has reset or wrapped around. */ + if (data->last_bad_plcp_cnt_cck > bad_plcp_cck) + data->last_bad_plcp_cnt_cck = bad_plcp_cck; + else { + bad_plcp_cck -= data->last_bad_plcp_cnt_cck; + data->last_bad_plcp_cnt_cck += bad_plcp_cck; + } + + if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm) + data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm; + else { + bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm; + data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm; + } + + if (data->last_fa_cnt_ofdm > fa_ofdm) + data->last_fa_cnt_ofdm = fa_ofdm; + else { + fa_ofdm -= data->last_fa_cnt_ofdm; + data->last_fa_cnt_ofdm += fa_ofdm; + } + + if (data->last_fa_cnt_cck > fa_cck) + data->last_fa_cnt_cck = fa_cck; + else { + fa_cck -= data->last_fa_cnt_cck; + data->last_fa_cnt_cck += fa_cck; + } + + /* Total aborted signal locks */ + norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm; + norm_fa_cck = fa_cck + bad_plcp_cck; + + IWL_DEBUG_CALIB("cck: fa %u badp %u ofdm: fa %u badp %u\n", fa_cck, + bad_plcp_cck, fa_ofdm, bad_plcp_ofdm); + + iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time); + iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis); + iwl_sensitivity_write(priv); + + return; +} +EXPORT_SYMBOL(iwl_sensitivity_calibration); + +/* + * Accumulate 20 beacons of signal and noise statistics for each of + * 3 receivers/antennas/rx-chains, then figure out: + * 1) Which antennas are connected. + * 2) Differential rx gain settings to balance the 3 receivers. + */ +void iwl_chain_noise_calibration(struct iwl_priv *priv, + struct iwl4965_notif_statistics *stat_resp) +{ + struct iwl_chain_noise_data *data = NULL; + + u32 chain_noise_a; + u32 chain_noise_b; + u32 chain_noise_c; + u32 chain_sig_a; + u32 chain_sig_b; + u32 chain_sig_c; + u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE}; + u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE}; + u32 max_average_sig; + u16 max_average_sig_antenna_i; + u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE; + u16 min_average_noise_antenna_i = INITIALIZATION_VALUE; + u16 i = 0; + u16 rxon_chnum = INITIALIZATION_VALUE; + u16 stat_chnum = INITIALIZATION_VALUE; + u8 rxon_band24; + u8 stat_band24; + u32 active_chains = 0; + u8 num_tx_chains; + unsigned long flags; + struct statistics_rx_non_phy *rx_info = &(stat_resp->rx.general); + + data = &(priv->chain_noise_data); + + /* Accumulate just the first 20 beacons after the first association, + * then we're done forever. */ + if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) { + if (data->state == IWL_CHAIN_NOISE_ALIVE) + IWL_DEBUG_CALIB("Wait for noise calib reset\n"); + return; + } + + spin_lock_irqsave(&priv->lock, flags); + if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) { + IWL_DEBUG_CALIB(" << Interference data unavailable\n"); + spin_unlock_irqrestore(&priv->lock, flags); + return; + } + + rxon_band24 = !!(priv->staging_rxon.flags & RXON_FLG_BAND_24G_MSK); + rxon_chnum = le16_to_cpu(priv->staging_rxon.channel); + stat_band24 = !!(stat_resp->flag & STATISTICS_REPLY_FLG_BAND_24G_MSK); + stat_chnum = le32_to_cpu(stat_resp->flag) >> 16; + + /* Make sure we accumulate data for just the associated channel + * (even if scanning). */ + if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) { + IWL_DEBUG_CALIB("Stats not from chan=%d, band24=%d\n", + rxon_chnum, rxon_band24); + spin_unlock_irqrestore(&priv->lock, flags); + return; + } + + /* Accumulate beacon statistics values across 20 beacons */ + chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) & + IN_BAND_FILTER; + chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) & + IN_BAND_FILTER; + chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) & + IN_BAND_FILTER; + + chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER; + chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER; + chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER; + + spin_unlock_irqrestore(&priv->lock, flags); + + data->beacon_count++; + + data->chain_noise_a = (chain_noise_a + data->chain_noise_a); + data->chain_noise_b = (chain_noise_b + data->chain_noise_b); + data->chain_noise_c = (chain_noise_c + data->chain_noise_c); + + data->chain_signal_a = (chain_sig_a + data->chain_signal_a); + data->chain_signal_b = (chain_sig_b + data->chain_signal_b); + data->chain_signal_c = (chain_sig_c + data->chain_signal_c); + + IWL_DEBUG_CALIB("chan=%d, band24=%d, beacon=%d\n", + rxon_chnum, rxon_band24, data->beacon_count); + IWL_DEBUG_CALIB("chain_sig: a %d b %d c %d\n", + chain_sig_a, chain_sig_b, chain_sig_c); + IWL_DEBUG_CALIB("chain_noise: a %d b %d c %d\n", + chain_noise_a, chain_noise_b, chain_noise_c); + + /* If this is the 20th beacon, determine: + * 1) Disconnected antennas (using signal strengths) + * 2) Differential gain (using silence noise) to balance receivers */ + if (data->beacon_count != CAL_NUM_OF_BEACONS) + return; + + /* Analyze signal for disconnected antenna */ + average_sig[0] = (data->chain_signal_a) / CAL_NUM_OF_BEACONS; + average_sig[1] = (data->chain_signal_b) / CAL_NUM_OF_BEACONS; + average_sig[2] = (data->chain_signal_c) / CAL_NUM_OF_BEACONS; + + if (average_sig[0] >= average_sig[1]) { + max_average_sig = average_sig[0]; + max_average_sig_antenna_i = 0; + active_chains = (1 << max_average_sig_antenna_i); + } else { + max_average_sig = average_sig[1]; + max_average_sig_antenna_i = 1; + active_chains = (1 << max_average_sig_antenna_i); + } + + if (average_sig[2] >= max_average_sig) { + max_average_sig = average_sig[2]; + max_average_sig_antenna_i = 2; + active_chains = (1 << max_average_sig_antenna_i); + } + + IWL_DEBUG_CALIB("average_sig: a %d b %d c %d\n", + average_sig[0], average_sig[1], average_sig[2]); + IWL_DEBUG_CALIB("max_average_sig = %d, antenna %d\n", + max_average_sig, max_average_sig_antenna_i); + + /* Compare signal strengths for all 3 receivers. */ + for (i = 0; i < NUM_RX_CHAINS; i++) { + if (i != max_average_sig_antenna_i) { + s32 rssi_delta = (max_average_sig - average_sig[i]); + + /* If signal is very weak, compared with + * strongest, mark it as disconnected. */ + if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS) + data->disconn_array[i] = 1; + else + active_chains |= (1 << i); + IWL_DEBUG_CALIB("i = %d rssiDelta = %d " + "disconn_array[i] = %d\n", + i, rssi_delta, data->disconn_array[i]); + } + } + + num_tx_chains = 0; + for (i = 0; i < NUM_RX_CHAINS; i++) { + /* loops on all the bits of + * priv->hw_setting.valid_tx_ant */ + u8 ant_msk = (1 << i); + if (!(priv->hw_params.valid_tx_ant & ant_msk)) + continue; + + num_tx_chains++; + if (data->disconn_array[i] == 0) + /* there is a Tx antenna connected */ + break; + if (num_tx_chains == priv->hw_params.tx_chains_num && + data->disconn_array[i]) { + /* This is the last TX antenna and is also + * disconnected connect it anyway */ + data->disconn_array[i] = 0; + active_chains |= ant_msk; + IWL_DEBUG_CALIB("All Tx chains are disconnected W/A - " + "declare %d as connected\n", i); + break; + } + } + + IWL_DEBUG_CALIB("active_chains (bitwise) = 0x%x\n", + active_chains); + + /* Save for use within RXON, TX, SCAN commands, etc. */ + priv->valid_antenna = active_chains; + + /* Analyze noise for rx balance */ + average_noise[0] = ((data->chain_noise_a)/CAL_NUM_OF_BEACONS); + average_noise[1] = ((data->chain_noise_b)/CAL_NUM_OF_BEACONS); + average_noise[2] = ((data->chain_noise_c)/CAL_NUM_OF_BEACONS); + + for (i = 0; i < NUM_RX_CHAINS; i++) { + if (!(data->disconn_array[i]) && + (average_noise[i] <= min_average_noise)) { + /* This means that chain i is active and has + * lower noise values so far: */ + min_average_noise = average_noise[i]; + min_average_noise_antenna_i = i; + } + } + + IWL_DEBUG_CALIB("average_noise: a %d b %d c %d\n", + average_noise[0], average_noise[1], + average_noise[2]); + + IWL_DEBUG_CALIB("min_average_noise = %d, antenna %d\n", + min_average_noise, min_average_noise_antenna_i); + + priv->cfg->ops->utils->gain_computation(priv, average_noise, + min_average_noise_antenna_i, min_average_noise); +} +EXPORT_SYMBOL(iwl_chain_noise_calibration); + |