drivers/net/wireless/iwlwifi/iwl-calib.c

   1 /******************************************************************************
   2  *
   3  * This file is provided under a dual BSD/GPLv2 license.  When using or
   4  * redistributing this file, you may do so under either license.
   5  *
   6  * GPL LICENSE SUMMARY
   7  *
   8  * Copyright(c) 2008 Intel Corporation. All rights reserved.
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of version 2 of the GNU General Public License as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
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  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
  22  * USA
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  25  * in the file called LICENSE.GPL.
  26  *
  27  * Contact Information:
  28  * Tomas Winkler <tomas.winkler@intel.com>
  29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  30  *
  31  * BSD LICENSE
  32  *
  33  * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
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  37  * modification, are permitted provided that the following conditions
  38  * are met:
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  41  *    notice, this list of conditions and the following disclaimer.
  42  *  * Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in
  44  *    the documentation and/or other materials provided with the
  45  *    distribution.
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  47  *    contributors may be used to endorse or promote products derived
  48  *    from this software without specific prior written permission.
  49  *
  50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  54  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  55  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  56  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  60  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  *****************************************************************************/
  62
  63 #include <net/mac80211.h>
  64
  65 #include "iwl-dev.h"
  66 #include "iwl-core.h"
  67 #include "iwl-calib.h"
  68
  69 /* "false alarms" are signals that our DSP tries to lock onto,
  70  *   but then determines that they are either noise, or transmissions
  71  *   from a distant wireless network (also "noise", really) that get
  72  *   "stepped on" by stronger transmissions within our own network.
  73  * This algorithm attempts to set a sensitivity level that is high
  74  *   enough to receive all of our own network traffic, but not so
  75  *   high that our DSP gets too busy trying to lock onto non-network
  76  *   activity/noise. */
  77 static int iwl_sens_energy_cck(struct iwl_priv *priv,
  78                                    u32 norm_fa,
  79                                    u32 rx_enable_time,
  80                                    struct statistics_general_data *rx_info)
  81 {
  82         u32 max_nrg_cck = 0;
  83         int i = 0;
  84         u8 max_silence_rssi = 0;
  85         u32 silence_ref = 0;
  86         u8 silence_rssi_a = 0;
  87         u8 silence_rssi_b = 0;
  88         u8 silence_rssi_c = 0;
  89         u32 val;
  90
  91         /* "false_alarms" values below are cross-multiplications to assess the
  92          *   numbers of false alarms within the measured period of actual Rx
  93          *   (Rx is off when we're txing), vs the min/max expected false alarms
  94          *   (some should be expected if rx is sensitive enough) in a
  95          *   hypothetical listening period of 200 time units (TU), 204.8 msec:
  96          *
  97          * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
  98          *
  99          * */
 100         u32 false_alarms = norm_fa * 200 * 1024;
 101         u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
 102         u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
 103         struct iwl_sensitivity_data *data = NULL;
 104         const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
 105
 106         data = &(priv->sensitivity_data);
 107
 108         data->nrg_auto_corr_silence_diff = 0;
 109
 110         /* Find max silence rssi among all 3 receivers.
 111          * This is background noise, which may include transmissions from other
 112          *    networks, measured during silence before our network's beacon */
 113         silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
 114                             ALL_BAND_FILTER) >> 8);
 115         silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
 116                             ALL_BAND_FILTER) >> 8);
 117         silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
 118                             ALL_BAND_FILTER) >> 8);
 119
 120         val = max(silence_rssi_b, silence_rssi_c);
 121         max_silence_rssi = max(silence_rssi_a, (u8) val);
 122
 123         /* Store silence rssi in 20-beacon history table */
 124         data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
 125         data->nrg_silence_idx++;
 126         if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
 127                 data->nrg_silence_idx = 0;
 128
 129         /* Find max silence rssi across 20 beacon history */
 130         for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
 131                 val = data->nrg_silence_rssi[i];
 132                 silence_ref = max(silence_ref, val);
 133         }
 134         IWL_DEBUG_CALIB("silence a %u, b %u, c %u, 20-bcn max %u\n",
 135                         silence_rssi_a, silence_rssi_b, silence_rssi_c,
 136                         silence_ref);
 137
 138         /* Find max rx energy (min value!) among all 3 receivers,
 139          *   measured during beacon frame.
 140          * Save it in 10-beacon history table. */
 141         i = data->nrg_energy_idx;
 142         val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
 143         data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
 144
 145         data->nrg_energy_idx++;
 146         if (data->nrg_energy_idx >= 10)
 147                 data->nrg_energy_idx = 0;
 148
 149         /* Find min rx energy (max value) across 10 beacon history.
 150          * This is the minimum signal level that we want to receive well.
 151          * Add backoff (margin so we don't miss slightly lower energy frames).
 152          * This establishes an upper bound (min value) for energy threshold. */
 153         max_nrg_cck = data->nrg_value[0];
 154         for (i = 1; i < 10; i++)
 155                 max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
 156         max_nrg_cck += 6;
 157
 158         IWL_DEBUG_CALIB("rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
 159                         rx_info->beacon_energy_a, rx_info->beacon_energy_b,
 160                         rx_info->beacon_energy_c, max_nrg_cck - 6);
 161
 162         /* Count number of consecutive beacons with fewer-than-desired
 163          *   false alarms. */
 164         if (false_alarms < min_false_alarms)
 165                 data->num_in_cck_no_fa++;
 166         else
 167                 data->num_in_cck_no_fa = 0;
 168         IWL_DEBUG_CALIB("consecutive bcns with few false alarms = %u\n",
 169                         data->num_in_cck_no_fa);
 170
 171         /* If we got too many false alarms this time, reduce sensitivity */
 172         if ((false_alarms > max_false_alarms) &&
 173                 (data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) {
 174                 IWL_DEBUG_CALIB("norm FA %u > max FA %u\n",
 175                      false_alarms, max_false_alarms);
 176                 IWL_DEBUG_CALIB("... reducing sensitivity\n");
 177                 data->nrg_curr_state = IWL_FA_TOO_MANY;
 178                 /* Store for "fewer than desired" on later beacon */
 179                 data->nrg_silence_ref = silence_ref;
 180
 181                 /* increase energy threshold (reduce nrg value)
 182                  *   to decrease sensitivity */
 183                 if (data->nrg_th_cck >
 184                         (ranges->max_nrg_cck + NRG_STEP_CCK))
 185                         data->nrg_th_cck = data->nrg_th_cck
 186                                                  - NRG_STEP_CCK;
 187                 else
 188                         data->nrg_th_cck = ranges->max_nrg_cck;
 189         /* Else if we got fewer than desired, increase sensitivity */
 190         } else if (false_alarms < min_false_alarms) {
 191                 data->nrg_curr_state = IWL_FA_TOO_FEW;
 192
 193                 /* Compare silence level with silence level for most recent
 194                  *   healthy number or too many false alarms */
 195                 data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
 196                                                    (s32)silence_ref;
 197
 198                 IWL_DEBUG_CALIB("norm FA %u < min FA %u, silence diff %d\n",
 199                          false_alarms, min_false_alarms,
 200                          data->nrg_auto_corr_silence_diff);
 201
 202                 /* Increase value to increase sensitivity, but only if:
 203                  * 1a) previous beacon did *not* have *too many* false alarms
 204                  * 1b) AND there's a significant difference in Rx levels
 205                  *      from a previous beacon with too many, or healthy # FAs
 206                  * OR 2) We've seen a lot of beacons (100) with too few
 207                  *       false alarms */
 208                 if ((data->nrg_prev_state != IWL_FA_TOO_MANY) &&
 209                         ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
 210                         (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
 211
 212                         IWL_DEBUG_CALIB("... increasing sensitivity\n");
 213                         /* Increase nrg value to increase sensitivity */
 214                         val = data->nrg_th_cck + NRG_STEP_CCK;
 215                         data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
 216                 } else {
 217                         IWL_DEBUG_CALIB("... but not changing sensitivity\n");
 218                 }
 219
 220         /* Else we got a healthy number of false alarms, keep status quo */
 221         } else {
 222                 IWL_DEBUG_CALIB(" FA in safe zone\n");
 223                 data->nrg_curr_state = IWL_FA_GOOD_RANGE;
 224
 225                 /* Store for use in "fewer than desired" with later beacon */
 226                 data->nrg_silence_ref = silence_ref;
 227
 228                 /* If previous beacon had too many false alarms,
 229                  *   give it some extra margin by reducing sensitivity again
 230                  *   (but don't go below measured energy of desired Rx) */
 231                 if (IWL_FA_TOO_MANY == data->nrg_prev_state) {
 232                         IWL_DEBUG_CALIB("... increasing margin\n");
 233                         if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
 234                                 data->nrg_th_cck -= NRG_MARGIN;
 235                         else
 236                                 data->nrg_th_cck = max_nrg_cck;
 237                 }
 238         }
 239
 240         /* Make sure the energy threshold does not go above the measured
 241          * energy of the desired Rx signals (reduced by backoff margin),
 242          * or else we might start missing Rx frames.
 243          * Lower value is higher energy, so we use max()!
 244          */
 245         data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
 246         IWL_DEBUG_CALIB("new nrg_th_cck %u\n", data->nrg_th_cck);
 247
 248         data->nrg_prev_state = data->nrg_curr_state;
 249
 250         /* Auto-correlation CCK algorithm */
 251         if (false_alarms > min_false_alarms) {
 252
 253                 /* increase auto_corr values to decrease sensitivity
 254                  * so the DSP won't be disturbed by the noise
 255                  */
 256                 if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
 257                         data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
 258                 else {
 259                         val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
 260                         data->auto_corr_cck =
 261                                 min((u32)ranges->auto_corr_max_cck, val);
 262                 }
 263                 val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
 264                 data->auto_corr_cck_mrc =
 265                         min((u32)ranges->auto_corr_max_cck_mrc, val);
 266         } else if ((false_alarms < min_false_alarms) &&
 267            ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
 268            (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
 269
 270                 /* Decrease auto_corr values to increase sensitivity */
 271                 val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
 272                 data->auto_corr_cck =
 273                         max((u32)ranges->auto_corr_min_cck, val);
 274                 val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
 275                 data->auto_corr_cck_mrc =
 276                         max((u32)ranges->auto_corr_min_cck_mrc, val);
 277         }
 278
 279         return 0;
 280 }
 281
 282
 283 static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv,
 284                                        u32 norm_fa,
 285                                        u32 rx_enable_time)
 286 {
 287         u32 val;
 288         u32 false_alarms = norm_fa * 200 * 1024;
 289         u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
 290         u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
 291         struct iwl_sensitivity_data *data = NULL;
 292         const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
 293
 294         data = &(priv->sensitivity_data);
 295
 296         /* If we got too many false alarms this time, reduce sensitivity */
 297         if (false_alarms > max_false_alarms) {
 298
 299                 IWL_DEBUG_CALIB("norm FA %u > max FA %u)\n",
 300                              false_alarms, max_false_alarms);
 301
 302                 val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
 303                 data->auto_corr_ofdm =
 304                         min((u32)ranges->auto_corr_max_ofdm, val);
 305
 306                 val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
 307                 data->auto_corr_ofdm_mrc =
 308                         min((u32)ranges->auto_corr_max_ofdm_mrc, val);
 309
 310                 val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
 311                 data->auto_corr_ofdm_x1 =
 312                         min((u32)ranges->auto_corr_max_ofdm_x1, val);
 313
 314                 val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
 315                 data->auto_corr_ofdm_mrc_x1 =
 316                         min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
 317         }
 318
 319         /* Else if we got fewer than desired, increase sensitivity */
 320         else if (false_alarms < min_false_alarms) {
 321
 322                 IWL_DEBUG_CALIB("norm FA %u < min FA %u\n",
 323                              false_alarms, min_false_alarms);
 324
 325                 val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
 326                 data->auto_corr_ofdm =
 327                         max((u32)ranges->auto_corr_min_ofdm, val);
 328
 329                 val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
 330                 data->auto_corr_ofdm_mrc =
 331                         max((u32)ranges->auto_corr_min_ofdm_mrc, val);
 332
 333                 val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
 334                 data->auto_corr_ofdm_x1 =
 335                         max((u32)ranges->auto_corr_min_ofdm_x1, val);
 336
 337                 val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
 338                 data->auto_corr_ofdm_mrc_x1 =
 339                         max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
 340         } else {
 341                 IWL_DEBUG_CALIB("min FA %u < norm FA %u < max FA %u OK\n",
 342                          min_false_alarms, false_alarms, max_false_alarms);
 343         }
 344         return 0;
 345 }
 346
 347 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
 348 static int iwl_sensitivity_write(struct iwl_priv *priv)
 349 {
 350         int ret = 0;
 351         struct iwl_sensitivity_cmd cmd ;
 352         struct iwl_sensitivity_data *data = NULL;
 353         struct iwl_host_cmd cmd_out = {
 354                 .id = SENSITIVITY_CMD,
 355                 .len = sizeof(struct iwl_sensitivity_cmd),
 356                 .meta.flags = CMD_ASYNC,
 357                 .data = &cmd,
 358         };
 359
 360         data = &(priv->sensitivity_data);
 361
 362         memset(&cmd, 0, sizeof(cmd));
 363
 364         cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] =
 365                                 cpu_to_le16((u16)data->auto_corr_ofdm);
 366         cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] =
 367                                 cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
 368         cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] =
 369                                 cpu_to_le16((u16)data->auto_corr_ofdm_x1);
 370         cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] =
 371                                 cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);
 372
 373         cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] =
 374                                 cpu_to_le16((u16)data->auto_corr_cck);
 375         cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] =
 376                                 cpu_to_le16((u16)data->auto_corr_cck_mrc);
 377
 378         cmd.table[HD_MIN_ENERGY_CCK_DET_INDEX] =
 379                                 cpu_to_le16((u16)data->nrg_th_cck);
 380         cmd.table[HD_MIN_ENERGY_OFDM_DET_INDEX] =
 381                                 cpu_to_le16((u16)data->nrg_th_ofdm);
 382
 383         cmd.table[HD_BARKER_CORR_TH_ADD_MIN_INDEX] =
 384                                 __constant_cpu_to_le16(190);
 385         cmd.table[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] =
 386                                 __constant_cpu_to_le16(390);
 387         cmd.table[HD_OFDM_ENERGY_TH_IN_INDEX] =
 388                                 __constant_cpu_to_le16(62);
 389
 390         IWL_DEBUG_CALIB("ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
 391                         data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
 392                         data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
 393                         data->nrg_th_ofdm);
 394
 395         IWL_DEBUG_CALIB("cck: ac %u mrc %u thresh %u\n",
 396                         data->auto_corr_cck, data->auto_corr_cck_mrc,
 397                         data->nrg_th_cck);
 398
 399         /* Update uCode's "work" table, and copy it to DSP */
 400         cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
 401
 402         /* Don't send command to uCode if nothing has changed */
 403         if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]),
 404                     sizeof(u16)*HD_TABLE_SIZE)) {
 405                 IWL_DEBUG_CALIB("No change in SENSITIVITY_CMD\n");
 406                 return 0;
 407         }
 408
 409         /* Copy table for comparison next time */
 410         memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]),
 411                sizeof(u16)*HD_TABLE_SIZE);
 412
 413         ret = iwl_send_cmd(priv, &cmd_out);
 414         if (ret)
 415                 IWL_ERROR("SENSITIVITY_CMD failed\n");
 416
 417         return ret;
 418 }
 419
 420 void iwl_init_sensitivity(struct iwl_priv *priv)
 421 {
 422         int ret = 0;
 423         int i;
 424         struct iwl_sensitivity_data *data = NULL;
 425         const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
 426
 427         if (priv->disable_sens_cal)
 428                 return;
 429
 430         IWL_DEBUG_CALIB("Start iwl_init_sensitivity\n");
 431
 432         /* Clear driver's sensitivity algo data */
 433         data = &(priv->sensitivity_data);
 434
 435         if (ranges == NULL)
 436                 return;
 437
 438         memset(data, 0, sizeof(struct iwl_sensitivity_data));
 439
 440         data->num_in_cck_no_fa = 0;
 441         data->nrg_curr_state = IWL_FA_TOO_MANY;
 442         data->nrg_prev_state = IWL_FA_TOO_MANY;
 443         data->nrg_silence_ref = 0;
 444         data->nrg_silence_idx = 0;
 445         data->nrg_energy_idx = 0;
 446
 447         for (i = 0; i < 10; i++)
 448                 data->nrg_value[i] = 0;
 449
 450         for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
 451                 data->nrg_silence_rssi[i] = 0;
 452
 453         data->auto_corr_ofdm = 90;
 454         data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
 455         data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
 456         data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
 457         data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
 458         data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
 459         data->nrg_th_cck = ranges->nrg_th_cck;
 460         data->nrg_th_ofdm = ranges->nrg_th_ofdm;
 461
 462         data->last_bad_plcp_cnt_ofdm = 0;
 463         data->last_fa_cnt_ofdm = 0;
 464         data->last_bad_plcp_cnt_cck = 0;
 465         data->last_fa_cnt_cck = 0;
 466
 467         ret |= iwl_sensitivity_write(priv);
 468         IWL_DEBUG_CALIB("<<return 0x%X\n", ret);
 469 }
 470 EXPORT_SYMBOL(iwl_init_sensitivity);
 471
 472 void iwl_sensitivity_calibration(struct iwl_priv *priv,
 473                                     struct iwl_notif_statistics *resp)
 474 {
 475         u32 rx_enable_time;
 476         u32 fa_cck;
 477         u32 fa_ofdm;
 478         u32 bad_plcp_cck;
 479         u32 bad_plcp_ofdm;
 480         u32 norm_fa_ofdm;
 481         u32 norm_fa_cck;
 482         struct iwl_sensitivity_data *data = NULL;
 483         struct statistics_rx_non_phy *rx_info = &(resp->rx.general);
 484         struct statistics_rx *statistics = &(resp->rx);
 485         unsigned long flags;
 486         struct statistics_general_data statis;
 487
 488         if (priv->disable_sens_cal)
 489                 return;
 490
 491         data = &(priv->sensitivity_data);
 492
 493         if (!iwl_is_associated(priv)) {
 494                 IWL_DEBUG_CALIB("<< - not associated\n");
 495                 return;
 496         }
 497
 498         spin_lock_irqsave(&priv->lock, flags);
 499         if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
 500                 IWL_DEBUG_CALIB("<< invalid data.\n");
 501                 spin_unlock_irqrestore(&priv->lock, flags);
 502                 return;
 503         }
 504
 505         /* Extract Statistics: */
 506         rx_enable_time = le32_to_cpu(rx_info->channel_load);
 507         fa_cck = le32_to_cpu(statistics->cck.false_alarm_cnt);
 508         fa_ofdm = le32_to_cpu(statistics->ofdm.false_alarm_cnt);
 509         bad_plcp_cck = le32_to_cpu(statistics->cck.plcp_err);
 510         bad_plcp_ofdm = le32_to_cpu(statistics->ofdm.plcp_err);
 511
 512         statis.beacon_silence_rssi_a =
 513                         le32_to_cpu(statistics->general.beacon_silence_rssi_a);
 514         statis.beacon_silence_rssi_b =
 515                         le32_to_cpu(statistics->general.beacon_silence_rssi_b);
 516         statis.beacon_silence_rssi_c =
 517                         le32_to_cpu(statistics->general.beacon_silence_rssi_c);
 518         statis.beacon_energy_a =
 519                         le32_to_cpu(statistics->general.beacon_energy_a);
 520         statis.beacon_energy_b =
 521                         le32_to_cpu(statistics->general.beacon_energy_b);
 522         statis.beacon_energy_c =
 523                         le32_to_cpu(statistics->general.beacon_energy_c);
 524
 525         spin_unlock_irqrestore(&priv->lock, flags);
 526
 527         IWL_DEBUG_CALIB("rx_enable_time = %u usecs\n", rx_enable_time);
 528
 529         if (!rx_enable_time) {
 530                 IWL_DEBUG_CALIB("<< RX Enable Time == 0! \n");
 531                 return;
 532         }
 533
 534         /* These statistics increase monotonically, and do not reset
 535          *   at each beacon.  Calculate difference from last value, or just
 536          *   use the new statistics value if it has reset or wrapped around. */
 537         if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
 538                 data->last_bad_plcp_cnt_cck = bad_plcp_cck;
 539         else {
 540                 bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
 541                 data->last_bad_plcp_cnt_cck += bad_plcp_cck;
 542         }
 543
 544         if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
 545                 data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
 546         else {
 547                 bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
 548                 data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
 549         }
 550
 551         if (data->last_fa_cnt_ofdm > fa_ofdm)
 552                 data->last_fa_cnt_ofdm = fa_ofdm;
 553         else {
 554                 fa_ofdm -= data->last_fa_cnt_ofdm;
 555                 data->last_fa_cnt_ofdm += fa_ofdm;
 556         }
 557
 558         if (data->last_fa_cnt_cck > fa_cck)
 559                 data->last_fa_cnt_cck = fa_cck;
 560         else {
 561                 fa_cck -= data->last_fa_cnt_cck;
 562                 data->last_fa_cnt_cck += fa_cck;
 563         }
 564
 565         /* Total aborted signal locks */
 566         norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
 567         norm_fa_cck = fa_cck + bad_plcp_cck;
 568
 569         IWL_DEBUG_CALIB("cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
 570                         bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
 571
 572         iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time);
 573         iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis);
 574         iwl_sensitivity_write(priv);
 575
 576         return;
 577 }
 578 EXPORT_SYMBOL(iwl_sensitivity_calibration);
 579
 580 /*
 581  * Accumulate 20 beacons of signal and noise statistics for each of
 582  *   3 receivers/antennas/rx-chains, then figure out:
 583  * 1)  Which antennas are connected.
 584  * 2)  Differential rx gain settings to balance the 3 receivers.
 585  */
 586 void iwl_chain_noise_calibration(struct iwl_priv *priv,
 587                                  struct iwl_notif_statistics *stat_resp)
 588 {
 589         struct iwl_chain_noise_data *data = NULL;
 590
 591         u32 chain_noise_a;
 592         u32 chain_noise_b;
 593         u32 chain_noise_c;
 594         u32 chain_sig_a;
 595         u32 chain_sig_b;
 596         u32 chain_sig_c;
 597         u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
 598         u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
 599         u32 max_average_sig;
 600         u16 max_average_sig_antenna_i;
 601         u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
 602         u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
 603         u16 i = 0;
 604         u16 rxon_chnum = INITIALIZATION_VALUE;
 605         u16 stat_chnum = INITIALIZATION_VALUE;
 606         u8 rxon_band24;
 607         u8 stat_band24;
 608         u32 active_chains = 0;
 609         u8 num_tx_chains;
 610         unsigned long flags;
 611         struct statistics_rx_non_phy *rx_info = &(stat_resp->rx.general);
 612
 613         if (priv->disable_chain_noise_cal)
 614                 return;
 615
 616         data = &(priv->chain_noise_data);
 617
 618         /* Accumulate just the first 20 beacons after the first association,
 619          *   then we're done forever. */
 620         if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) {
 621                 if (data->state == IWL_CHAIN_NOISE_ALIVE)
 622                         IWL_DEBUG_CALIB("Wait for noise calib reset\n");
 623                 return;
 624         }
 625
 626         spin_lock_irqsave(&priv->lock, flags);
 627         if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
 628                 IWL_DEBUG_CALIB(" << Interference data unavailable\n");
 629                 spin_unlock_irqrestore(&priv->lock, flags);
 630                 return;
 631         }
 632
 633         rxon_band24 = !!(priv->staging_rxon.flags & RXON_FLG_BAND_24G_MSK);
 634         rxon_chnum = le16_to_cpu(priv->staging_rxon.channel);
 635         stat_band24 = !!(stat_resp->flag & STATISTICS_REPLY_FLG_BAND_24G_MSK);
 636         stat_chnum = le32_to_cpu(stat_resp->flag) >> 16;
 637
 638         /* Make sure we accumulate data for just the associated channel
 639          *   (even if scanning). */
 640         if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) {
 641                 IWL_DEBUG_CALIB("Stats not from chan=%d, band24=%d\n",
 642                                 rxon_chnum, rxon_band24);
 643                 spin_unlock_irqrestore(&priv->lock, flags);
 644                 return;
 645         }
 646
 647         /* Accumulate beacon statistics values across 20 beacons */
 648         chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
 649                                 IN_BAND_FILTER;
 650         chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
 651                                 IN_BAND_FILTER;
 652         chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
 653                                 IN_BAND_FILTER;
 654
 655         chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
 656         chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
 657         chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
 658
 659         spin_unlock_irqrestore(&priv->lock, flags);
 660
 661         data->beacon_count++;
 662
 663         data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
 664         data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
 665         data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
 666
 667         data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
 668         data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
 669         data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
 670
 671         IWL_DEBUG_CALIB("chan=%d, band24=%d, beacon=%d\n",
 672                         rxon_chnum, rxon_band24, data->beacon_count);
 673         IWL_DEBUG_CALIB("chain_sig: a %d b %d c %d\n",
 674                         chain_sig_a, chain_sig_b, chain_sig_c);
 675         IWL_DEBUG_CALIB("chain_noise: a %d b %d c %d\n",
 676                         chain_noise_a, chain_noise_b, chain_noise_c);
 677
 678         /* If this is the 20th beacon, determine:
 679          * 1)  Disconnected antennas (using signal strengths)
 680          * 2)  Differential gain (using silence noise) to balance receivers */
 681         if (data->beacon_count != CAL_NUM_OF_BEACONS)
 682                 return;
 683
 684         /* Analyze signal for disconnected antenna */
 685         average_sig[0] = (data->chain_signal_a) / CAL_NUM_OF_BEACONS;
 686         average_sig[1] = (data->chain_signal_b) / CAL_NUM_OF_BEACONS;
 687         average_sig[2] = (data->chain_signal_c) / CAL_NUM_OF_BEACONS;
 688
 689         if (average_sig[0] >= average_sig[1]) {
 690                 max_average_sig = average_sig[0];
 691                 max_average_sig_antenna_i = 0;
 692                 active_chains = (1 << max_average_sig_antenna_i);
 693         } else {
 694                 max_average_sig = average_sig[1];
 695                 max_average_sig_antenna_i = 1;
 696                 active_chains = (1 << max_average_sig_antenna_i);
 697         }
 698
 699         if (average_sig[2] >= max_average_sig) {
 700                 max_average_sig = average_sig[2];
 701                 max_average_sig_antenna_i = 2;
 702                 active_chains = (1 << max_average_sig_antenna_i);
 703         }
 704
 705         IWL_DEBUG_CALIB("average_sig: a %d b %d c %d\n",
 706                      average_sig[0], average_sig[1], average_sig[2]);
 707         IWL_DEBUG_CALIB("max_average_sig = %d, antenna %d\n",
 708                      max_average_sig, max_average_sig_antenna_i);
 709
 710         /* Compare signal strengths for all 3 receivers. */
 711         for (i = 0; i < NUM_RX_CHAINS; i++) {
 712                 if (i != max_average_sig_antenna_i) {
 713                         s32 rssi_delta = (max_average_sig - average_sig[i]);
 714
 715                         /* If signal is very weak, compared with
 716                          * strongest, mark it as disconnected. */
 717                         if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
 718                                 data->disconn_array[i] = 1;
 719                         else
 720                                 active_chains |= (1 << i);
 721                         IWL_DEBUG_CALIB("i = %d  rssiDelta = %d  "
 722                              "disconn_array[i] = %d\n",
 723                              i, rssi_delta, data->disconn_array[i]);
 724                 }
 725         }
 726
 727         num_tx_chains = 0;
 728         for (i = 0; i < NUM_RX_CHAINS; i++) {
 729                 /* loops on all the bits of
 730                  * priv->hw_setting.valid_tx_ant */
 731                 u8 ant_msk = (1 << i);
 732                 if (!(priv->hw_params.valid_tx_ant & ant_msk))
 733                         continue;
 734
 735                 num_tx_chains++;
 736                 if (data->disconn_array[i] == 0)
 737                         /* there is a Tx antenna connected */
 738                         break;
 739                 if (num_tx_chains == priv->hw_params.tx_chains_num &&
 740                 data->disconn_array[i]) {
 741                         /* This is the last TX antenna and is also
 742                          * disconnected connect it anyway */
 743                         data->disconn_array[i] = 0;
 744                         active_chains |= ant_msk;
 745                         IWL_DEBUG_CALIB("All Tx chains are disconnected W/A - "
 746                                 "declare %d as connected\n", i);
 747                         break;
 748                 }
 749         }
 750
 751         IWL_DEBUG_CALIB("active_chains (bitwise) = 0x%x\n",
 752                         active_chains);
 753
 754         /* Save for use within RXON, TX, SCAN commands, etc. */
 755         /*priv->valid_antenna = active_chains;*/
 756         /*FIXME: should be reflected in RX chains in RXON */
 757
 758         /* Analyze noise for rx balance */
 759         average_noise[0] = ((data->chain_noise_a)/CAL_NUM_OF_BEACONS);
 760         average_noise[1] = ((data->chain_noise_b)/CAL_NUM_OF_BEACONS);
 761         average_noise[2] = ((data->chain_noise_c)/CAL_NUM_OF_BEACONS);
 762
 763         for (i = 0; i < NUM_RX_CHAINS; i++) {
 764                 if (!(data->disconn_array[i]) &&
 765                    (average_noise[i] <= min_average_noise)) {
 766                         /* This means that chain i is active and has
 767                          * lower noise values so far: */
 768                         min_average_noise = average_noise[i];
 769                         min_average_noise_antenna_i = i;
 770                 }
 771         }
 772
 773         IWL_DEBUG_CALIB("average_noise: a %d b %d c %d\n",
 774                         average_noise[0], average_noise[1],
 775                         average_noise[2]);
 776
 777         IWL_DEBUG_CALIB("min_average_noise = %d, antenna %d\n",
 778                         min_average_noise, min_average_noise_antenna_i);
 779
 780         priv->cfg->ops->utils->gain_computation(priv, average_noise,
 781                 min_average_noise_antenna_i, min_average_noise);
 782 }
 783 EXPORT_SYMBOL(iwl_chain_noise_calibration);
 784
 785
 786 void iwl_reset_run_time_calib(struct iwl_priv *priv)
 787 {
 788         int i;
 789         memset(&(priv->sensitivity_data), 0,
 790                sizeof(struct iwl_sensitivity_data));
 791         memset(&(priv->chain_noise_data), 0,
 792                sizeof(struct iwl_chain_noise_data));
 793         for (i = 0; i < NUM_RX_CHAINS; i++)
 794                 priv->chain_noise_data.delta_gain_code[i] =
 795                                 CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
 796
 797         /* Ask for statistics now, the uCode will send notification
 798          * periodically after association */
 799         iwl_send_statistics_request(priv, CMD_ASYNC);
 800 }
 801 EXPORT_SYMBOL(iwl_reset_run_time_calib);
 802