/****************************************************************************** * * 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 * 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 #include #include "iwl-dev.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; if (priv->disable_sens_cal) return; 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("<rx.general); struct statistics_rx *statistics = &(resp->rx); unsigned long flags; struct statistics_general_data statis; if (priv->disable_sens_cal) return; 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); if (priv->disable_chain_noise_cal) return; 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;*/ /*FIXME: should be reflected in RX chains in RXON */ /* 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);