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 - 2010 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
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  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
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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  *  Intel Linux Wireless <ilw@linux.intel.com>
  29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  30  *
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  32  *
  33  * Copyright(c) 2005 - 2010 Intel Corporation. All rights reserved.
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  37  * modification, are permitted provided that the following conditions
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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 /*****************************************************************************
  70  * INIT calibrations framework
  71  *****************************************************************************/
  72
  73 struct statistics_general_data {
  74         u32 beacon_silence_rssi_a;
  75         u32 beacon_silence_rssi_b;
  76         u32 beacon_silence_rssi_c;
  77         u32 beacon_energy_a;
  78         u32 beacon_energy_b;
  79         u32 beacon_energy_c;
  80 };
  81
  82 int iwl_send_calib_results(struct iwl_priv *priv)
  83 {
  84         int ret = 0;
  85         int i = 0;
  86
  87         struct iwl_host_cmd hcmd = {
  88                 .id = REPLY_PHY_CALIBRATION_CMD,
  89                 .flags = CMD_SIZE_HUGE,
  90         };
  91
  92         for (i = 0; i < IWL_CALIB_MAX; i++) {
  93                 if ((BIT(i) & priv->hw_params.calib_init_cfg) &&
  94                     priv->calib_results[i].buf) {
  95                         hcmd.len = priv->calib_results[i].buf_len;
  96                         hcmd.data = priv->calib_results[i].buf;
  97                         ret = iwl_send_cmd_sync(priv, &hcmd);
  98                         if (ret)
  99                                 goto err;
 100                 }
 101         }
 102
 103         return 0;
 104 err:
 105         IWL_ERR(priv, "Error %d iteration %d\n", ret, i);
 106         return ret;
 107 }
 108 EXPORT_SYMBOL(iwl_send_calib_results);
 109
 110 int iwl_calib_set(struct iwl_calib_result *res, const u8 *buf, int len)
 111 {
 112         if (res->buf_len != len) {
 113                 kfree(res->buf);
 114                 res->buf = kzalloc(len, GFP_ATOMIC);
 115         }
 116         if (unlikely(res->buf == NULL))
 117                 return -ENOMEM;
 118
 119         res->buf_len = len;
 120         memcpy(res->buf, buf, len);
 121         return 0;
 122 }
 123 EXPORT_SYMBOL(iwl_calib_set);
 124
 125 void iwl_calib_free_results(struct iwl_priv *priv)
 126 {
 127         int i;
 128
 129         for (i = 0; i < IWL_CALIB_MAX; i++) {
 130                 kfree(priv->calib_results[i].buf);
 131                 priv->calib_results[i].buf = NULL;
 132                 priv->calib_results[i].buf_len = 0;
 133         }
 134 }
 135 EXPORT_SYMBOL(iwl_calib_free_results);
 136
 137 /*****************************************************************************
 138  * RUNTIME calibrations framework
 139  *****************************************************************************/
 140
 141 /* "false alarms" are signals that our DSP tries to lock onto,
 142  *   but then determines that they are either noise, or transmissions
 143  *   from a distant wireless network (also "noise", really) that get
 144  *   "stepped on" by stronger transmissions within our own network.
 145  * This algorithm attempts to set a sensitivity level that is high
 146  *   enough to receive all of our own network traffic, but not so
 147  *   high that our DSP gets too busy trying to lock onto non-network
 148  *   activity/noise. */
 149 static int iwl_sens_energy_cck(struct iwl_priv *priv,
 150                                    u32 norm_fa,
 151                                    u32 rx_enable_time,
 152                                    struct statistics_general_data *rx_info)
 153 {
 154         u32 max_nrg_cck = 0;
 155         int i = 0;
 156         u8 max_silence_rssi = 0;
 157         u32 silence_ref = 0;
 158         u8 silence_rssi_a = 0;
 159         u8 silence_rssi_b = 0;
 160         u8 silence_rssi_c = 0;
 161         u32 val;
 162
 163         /* "false_alarms" values below are cross-multiplications to assess the
 164          *   numbers of false alarms within the measured period of actual Rx
 165          *   (Rx is off when we're txing), vs the min/max expected false alarms
 166          *   (some should be expected if rx is sensitive enough) in a
 167          *   hypothetical listening period of 200 time units (TU), 204.8 msec:
 168          *
 169          * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
 170          *
 171          * */
 172         u32 false_alarms = norm_fa * 200 * 1024;
 173         u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
 174         u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
 175         struct iwl_sensitivity_data *data = NULL;
 176         const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
 177
 178         data = &(priv->sensitivity_data);
 179
 180         data->nrg_auto_corr_silence_diff = 0;
 181
 182         /* Find max silence rssi among all 3 receivers.
 183          * This is background noise, which may include transmissions from other
 184          *    networks, measured during silence before our network's beacon */
 185         silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
 186                             ALL_BAND_FILTER) >> 8);
 187         silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
 188                             ALL_BAND_FILTER) >> 8);
 189         silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
 190                             ALL_BAND_FILTER) >> 8);
 191
 192         val = max(silence_rssi_b, silence_rssi_c);
 193         max_silence_rssi = max(silence_rssi_a, (u8) val);
 194
 195         /* Store silence rssi in 20-beacon history table */
 196         data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
 197         data->nrg_silence_idx++;
 198         if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
 199                 data->nrg_silence_idx = 0;
 200
 201         /* Find max silence rssi across 20 beacon history */
 202         for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
 203                 val = data->nrg_silence_rssi[i];
 204                 silence_ref = max(silence_ref, val);
 205         }
 206         IWL_DEBUG_CALIB(priv, "silence a %u, b %u, c %u, 20-bcn max %u\n",
 207                         silence_rssi_a, silence_rssi_b, silence_rssi_c,
 208                         silence_ref);
 209
 210         /* Find max rx energy (min value!) among all 3 receivers,
 211          *   measured during beacon frame.
 212          * Save it in 10-beacon history table. */
 213         i = data->nrg_energy_idx;
 214         val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
 215         data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
 216
 217         data->nrg_energy_idx++;
 218         if (data->nrg_energy_idx >= 10)
 219                 data->nrg_energy_idx = 0;
 220
 221         /* Find min rx energy (max value) across 10 beacon history.
 222          * This is the minimum signal level that we want to receive well.
 223          * Add backoff (margin so we don't miss slightly lower energy frames).
 224          * This establishes an upper bound (min value) for energy threshold. */
 225         max_nrg_cck = data->nrg_value[0];
 226         for (i = 1; i < 10; i++)
 227                 max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
 228         max_nrg_cck += 6;
 229
 230         IWL_DEBUG_CALIB(priv, "rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
 231                         rx_info->beacon_energy_a, rx_info->beacon_energy_b,
 232                         rx_info->beacon_energy_c, max_nrg_cck - 6);
 233
 234         /* Count number of consecutive beacons with fewer-than-desired
 235          *   false alarms. */
 236         if (false_alarms < min_false_alarms)
 237                 data->num_in_cck_no_fa++;
 238         else
 239                 data->num_in_cck_no_fa = 0;
 240         IWL_DEBUG_CALIB(priv, "consecutive bcns with few false alarms = %u\n",
 241                         data->num_in_cck_no_fa);
 242
 243         /* If we got too many false alarms this time, reduce sensitivity */
 244         if ((false_alarms > max_false_alarms) &&
 245                 (data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) {
 246                 IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u\n",
 247                      false_alarms, max_false_alarms);
 248                 IWL_DEBUG_CALIB(priv, "... reducing sensitivity\n");
 249                 data->nrg_curr_state = IWL_FA_TOO_MANY;
 250                 /* Store for "fewer than desired" on later beacon */
 251                 data->nrg_silence_ref = silence_ref;
 252
 253                 /* increase energy threshold (reduce nrg value)
 254                  *   to decrease sensitivity */
 255                 data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
 256         /* Else if we got fewer than desired, increase sensitivity */
 257         } else if (false_alarms < min_false_alarms) {
 258                 data->nrg_curr_state = IWL_FA_TOO_FEW;
 259
 260                 /* Compare silence level with silence level for most recent
 261                  *   healthy number or too many false alarms */
 262                 data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
 263                                                    (s32)silence_ref;
 264
 265                 IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u, silence diff %d\n",
 266                          false_alarms, min_false_alarms,
 267                          data->nrg_auto_corr_silence_diff);
 268
 269                 /* Increase value to increase sensitivity, but only if:
 270                  * 1a) previous beacon did *not* have *too many* false alarms
 271                  * 1b) AND there's a significant difference in Rx levels
 272                  *      from a previous beacon with too many, or healthy # FAs
 273                  * OR 2) We've seen a lot of beacons (100) with too few
 274                  *       false alarms */
 275                 if ((data->nrg_prev_state != IWL_FA_TOO_MANY) &&
 276                         ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
 277                         (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
 278
 279                         IWL_DEBUG_CALIB(priv, "... increasing sensitivity\n");
 280                         /* Increase nrg value to increase sensitivity */
 281                         val = data->nrg_th_cck + NRG_STEP_CCK;
 282                         data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
 283                 } else {
 284                         IWL_DEBUG_CALIB(priv, "... but not changing sensitivity\n");
 285                 }
 286
 287         /* Else we got a healthy number of false alarms, keep status quo */
 288         } else {
 289                 IWL_DEBUG_CALIB(priv, " FA in safe zone\n");
 290                 data->nrg_curr_state = IWL_FA_GOOD_RANGE;
 291
 292                 /* Store for use in "fewer than desired" with later beacon */
 293                 data->nrg_silence_ref = silence_ref;
 294
 295                 /* If previous beacon had too many false alarms,
 296                  *   give it some extra margin by reducing sensitivity again
 297                  *   (but don't go below measured energy of desired Rx) */
 298                 if (IWL_FA_TOO_MANY == data->nrg_prev_state) {
 299                         IWL_DEBUG_CALIB(priv, "... increasing margin\n");
 300                         if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
 301                                 data->nrg_th_cck -= NRG_MARGIN;
 302                         else
 303                                 data->nrg_th_cck = max_nrg_cck;
 304                 }
 305         }
 306
 307         /* Make sure the energy threshold does not go above the measured
 308          * energy of the desired Rx signals (reduced by backoff margin),
 309          * or else we might start missing Rx frames.
 310          * Lower value is higher energy, so we use max()!
 311          */
 312         data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
 313         IWL_DEBUG_CALIB(priv, "new nrg_th_cck %u\n", data->nrg_th_cck);
 314
 315         data->nrg_prev_state = data->nrg_curr_state;
 316
 317         /* Auto-correlation CCK algorithm */
 318         if (false_alarms > min_false_alarms) {
 319
 320                 /* increase auto_corr values to decrease sensitivity
 321                  * so the DSP won't be disturbed by the noise
 322                  */
 323                 if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
 324                         data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
 325                 else {
 326                         val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
 327                         data->auto_corr_cck =
 328                                 min((u32)ranges->auto_corr_max_cck, val);
 329                 }
 330                 val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
 331                 data->auto_corr_cck_mrc =
 332                         min((u32)ranges->auto_corr_max_cck_mrc, val);
 333         } else if ((false_alarms < min_false_alarms) &&
 334            ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
 335            (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
 336
 337                 /* Decrease auto_corr values to increase sensitivity */
 338                 val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
 339                 data->auto_corr_cck =
 340                         max((u32)ranges->auto_corr_min_cck, val);
 341                 val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
 342                 data->auto_corr_cck_mrc =
 343                         max((u32)ranges->auto_corr_min_cck_mrc, val);
 344         }
 345
 346         return 0;
 347 }
 348
 349
 350 static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv,
 351                                        u32 norm_fa,
 352                                        u32 rx_enable_time)
 353 {
 354         u32 val;
 355         u32 false_alarms = norm_fa * 200 * 1024;
 356         u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
 357         u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
 358         struct iwl_sensitivity_data *data = NULL;
 359         const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
 360
 361         data = &(priv->sensitivity_data);
 362
 363         /* If we got too many false alarms this time, reduce sensitivity */
 364         if (false_alarms > max_false_alarms) {
 365
 366                 IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u)\n",
 367                              false_alarms, max_false_alarms);
 368
 369                 val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
 370                 data->auto_corr_ofdm =
 371                         min((u32)ranges->auto_corr_max_ofdm, val);
 372
 373                 val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
 374                 data->auto_corr_ofdm_mrc =
 375                         min((u32)ranges->auto_corr_max_ofdm_mrc, val);
 376
 377                 val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
 378                 data->auto_corr_ofdm_x1 =
 379                         min((u32)ranges->auto_corr_max_ofdm_x1, val);
 380
 381                 val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
 382                 data->auto_corr_ofdm_mrc_x1 =
 383                         min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
 384         }
 385
 386         /* Else if we got fewer than desired, increase sensitivity */
 387         else if (false_alarms < min_false_alarms) {
 388
 389                 IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u\n",
 390                              false_alarms, min_false_alarms);
 391
 392                 val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
 393                 data->auto_corr_ofdm =
 394                         max((u32)ranges->auto_corr_min_ofdm, val);
 395
 396                 val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
 397                 data->auto_corr_ofdm_mrc =
 398                         max((u32)ranges->auto_corr_min_ofdm_mrc, val);
 399
 400                 val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
 401                 data->auto_corr_ofdm_x1 =
 402                         max((u32)ranges->auto_corr_min_ofdm_x1, val);
 403
 404                 val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
 405                 data->auto_corr_ofdm_mrc_x1 =
 406                         max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
 407         } else {
 408                 IWL_DEBUG_CALIB(priv, "min FA %u < norm FA %u < max FA %u OK\n",
 409                          min_false_alarms, false_alarms, max_false_alarms);
 410         }
 411         return 0;
 412 }
 413
 414 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
 415 static int iwl_sensitivity_write(struct iwl_priv *priv)
 416 {
 417         struct iwl_sensitivity_cmd cmd ;
 418         struct iwl_sensitivity_data *data = NULL;
 419         struct iwl_host_cmd cmd_out = {
 420                 .id = SENSITIVITY_CMD,
 421                 .len = sizeof(struct iwl_sensitivity_cmd),
 422                 .flags = CMD_ASYNC,
 423                 .data = &cmd,
 424         };
 425
 426         data = &(priv->sensitivity_data);
 427
 428         memset(&cmd, 0, sizeof(cmd));
 429
 430         cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] =
 431                                 cpu_to_le16((u16)data->auto_corr_ofdm);
 432         cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] =
 433                                 cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
 434         cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] =
 435                                 cpu_to_le16((u16)data->auto_corr_ofdm_x1);
 436         cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] =
 437                                 cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);
 438
 439         cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] =
 440                                 cpu_to_le16((u16)data->auto_corr_cck);
 441         cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] =
 442                                 cpu_to_le16((u16)data->auto_corr_cck_mrc);
 443
 444         cmd.table[HD_MIN_ENERGY_CCK_DET_INDEX] =
 445                                 cpu_to_le16((u16)data->nrg_th_cck);
 446         cmd.table[HD_MIN_ENERGY_OFDM_DET_INDEX] =
 447                                 cpu_to_le16((u16)data->nrg_th_ofdm);
 448
 449         cmd.table[HD_BARKER_CORR_TH_ADD_MIN_INDEX] =
 450                                 cpu_to_le16(data->barker_corr_th_min);
 451         cmd.table[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] =
 452                                 cpu_to_le16(data->barker_corr_th_min_mrc);
 453         cmd.table[HD_OFDM_ENERGY_TH_IN_INDEX] =
 454                                 cpu_to_le16(data->nrg_th_cca);
 455
 456         IWL_DEBUG_CALIB(priv, "ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
 457                         data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
 458                         data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
 459                         data->nrg_th_ofdm);
 460
 461         IWL_DEBUG_CALIB(priv, "cck: ac %u mrc %u thresh %u\n",
 462                         data->auto_corr_cck, data->auto_corr_cck_mrc,
 463                         data->nrg_th_cck);
 464
 465         /* Update uCode's "work" table, and copy it to DSP */
 466         cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
 467
 468         /* Don't send command to uCode if nothing has changed */
 469         if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]),
 470                     sizeof(u16)*HD_TABLE_SIZE)) {
 471                 IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
 472                 return 0;
 473         }
 474
 475         /* Copy table for comparison next time */
 476         memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]),
 477                sizeof(u16)*HD_TABLE_SIZE);
 478
 479         return iwl_send_cmd(priv, &cmd_out);
 480 }
 481
 482 void iwl_init_sensitivity(struct iwl_priv *priv)
 483 {
 484         int ret = 0;
 485         int i;
 486         struct iwl_sensitivity_data *data = NULL;
 487         const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
 488
 489         if (priv->disable_sens_cal)
 490                 return;
 491
 492         IWL_DEBUG_CALIB(priv, "Start iwl_init_sensitivity\n");
 493
 494         /* Clear driver's sensitivity algo data */
 495         data = &(priv->sensitivity_data);
 496
 497         if (ranges == NULL)
 498                 return;
 499
 500         memset(data, 0, sizeof(struct iwl_sensitivity_data));
 501
 502         data->num_in_cck_no_fa = 0;
 503         data->nrg_curr_state = IWL_FA_TOO_MANY;
 504         data->nrg_prev_state = IWL_FA_TOO_MANY;
 505         data->nrg_silence_ref = 0;
 506         data->nrg_silence_idx = 0;
 507         data->nrg_energy_idx = 0;
 508
 509         for (i = 0; i < 10; i++)
 510                 data->nrg_value[i] = 0;
 511
 512         for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
 513                 data->nrg_silence_rssi[i] = 0;
 514
 515         data->auto_corr_ofdm =  ranges->auto_corr_min_ofdm;
 516         data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
 517         data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
 518         data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
 519         data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
 520         data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
 521         data->nrg_th_cck = ranges->nrg_th_cck;
 522         data->nrg_th_ofdm = ranges->nrg_th_ofdm;
 523         data->barker_corr_th_min = ranges->barker_corr_th_min;
 524         data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
 525         data->nrg_th_cca = ranges->nrg_th_cca;
 526
 527         data->last_bad_plcp_cnt_ofdm = 0;
 528         data->last_fa_cnt_ofdm = 0;
 529         data->last_bad_plcp_cnt_cck = 0;
 530         data->last_fa_cnt_cck = 0;
 531
 532         ret |= iwl_sensitivity_write(priv);
 533         IWL_DEBUG_CALIB(priv, "<<return 0x%X\n", ret);
 534 }
 535 EXPORT_SYMBOL(iwl_init_sensitivity);
 536
 537 void iwl_sensitivity_calibration(struct iwl_priv *priv,
 538                                     struct iwl_notif_statistics *resp)
 539 {
 540         u32 rx_enable_time;
 541         u32 fa_cck;
 542         u32 fa_ofdm;
 543         u32 bad_plcp_cck;
 544         u32 bad_plcp_ofdm;
 545         u32 norm_fa_ofdm;
 546         u32 norm_fa_cck;
 547         struct iwl_sensitivity_data *data = NULL;
 548         struct statistics_rx_non_phy *rx_info = &(resp->rx.general);
 549         struct statistics_rx *statistics = &(resp->rx);
 550         unsigned long flags;
 551         struct statistics_general_data statis;
 552
 553         if (priv->disable_sens_cal)
 554                 return;
 555
 556         data = &(priv->sensitivity_data);
 557
 558         if (!iwl_is_associated(priv)) {
 559                 IWL_DEBUG_CALIB(priv, "<< - not associated\n");
 560                 return;
 561         }
 562
 563         spin_lock_irqsave(&priv->lock, flags);
 564         if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
 565                 IWL_DEBUG_CALIB(priv, "<< invalid data.\n");
 566                 spin_unlock_irqrestore(&priv->lock, flags);
 567                 return;
 568         }
 569
 570         /* Extract Statistics: */
 571         rx_enable_time = le32_to_cpu(rx_info->channel_load);
 572         fa_cck = le32_to_cpu(statistics->cck.false_alarm_cnt);
 573         fa_ofdm = le32_to_cpu(statistics->ofdm.false_alarm_cnt);
 574         bad_plcp_cck = le32_to_cpu(statistics->cck.plcp_err);
 575         bad_plcp_ofdm = le32_to_cpu(statistics->ofdm.plcp_err);
 576
 577         statis.beacon_silence_rssi_a =
 578                         le32_to_cpu(statistics->general.beacon_silence_rssi_a);
 579         statis.beacon_silence_rssi_b =
 580                         le32_to_cpu(statistics->general.beacon_silence_rssi_b);
 581         statis.beacon_silence_rssi_c =
 582                         le32_to_cpu(statistics->general.beacon_silence_rssi_c);
 583         statis.beacon_energy_a =
 584                         le32_to_cpu(statistics->general.beacon_energy_a);
 585         statis.beacon_energy_b =
 586                         le32_to_cpu(statistics->general.beacon_energy_b);
 587         statis.beacon_energy_c =
 588                         le32_to_cpu(statistics->general.beacon_energy_c);
 589
 590         spin_unlock_irqrestore(&priv->lock, flags);
 591
 592         IWL_DEBUG_CALIB(priv, "rx_enable_time = %u usecs\n", rx_enable_time);
 593
 594         if (!rx_enable_time) {
 595                 IWL_DEBUG_CALIB(priv, "<< RX Enable Time == 0! \n");
 596                 return;
 597         }
 598
 599         /* These statistics increase monotonically, and do not reset
 600          *   at each beacon.  Calculate difference from last value, or just
 601          *   use the new statistics value if it has reset or wrapped around. */
 602         if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
 603                 data->last_bad_plcp_cnt_cck = bad_plcp_cck;
 604         else {
 605                 bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
 606                 data->last_bad_plcp_cnt_cck += bad_plcp_cck;
 607         }
 608
 609         if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
 610                 data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
 611         else {
 612                 bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
 613                 data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
 614         }
 615
 616         if (data->last_fa_cnt_ofdm > fa_ofdm)
 617                 data->last_fa_cnt_ofdm = fa_ofdm;
 618         else {
 619                 fa_ofdm -= data->last_fa_cnt_ofdm;
 620                 data->last_fa_cnt_ofdm += fa_ofdm;
 621         }
 622
 623         if (data->last_fa_cnt_cck > fa_cck)
 624                 data->last_fa_cnt_cck = fa_cck;
 625         else {
 626                 fa_cck -= data->last_fa_cnt_cck;
 627                 data->last_fa_cnt_cck += fa_cck;
 628         }
 629
 630         /* Total aborted signal locks */
 631         norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
 632         norm_fa_cck = fa_cck + bad_plcp_cck;
 633
 634         IWL_DEBUG_CALIB(priv, "cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
 635                         bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
 636
 637         iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time);
 638         iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis);
 639         iwl_sensitivity_write(priv);
 640
 641         return;
 642 }
 643 EXPORT_SYMBOL(iwl_sensitivity_calibration);
 644
 645 static inline u8 find_first_chain(u8 mask)
 646 {
 647         if (mask & ANT_A)
 648                 return CHAIN_A;
 649         if (mask & ANT_B)
 650                 return CHAIN_B;
 651         return CHAIN_C;
 652 }
 653
 654 /*
 655  * Accumulate 20 beacons of signal and noise statistics for each of
 656  *   3 receivers/antennas/rx-chains, then figure out:
 657  * 1)  Which antennas are connected.
 658  * 2)  Differential rx gain settings to balance the 3 receivers.
 659  */
 660 void iwl_chain_noise_calibration(struct iwl_priv *priv,
 661                                  struct iwl_notif_statistics *stat_resp)
 662 {
 663         struct iwl_chain_noise_data *data = NULL;
 664
 665         u32 chain_noise_a;
 666         u32 chain_noise_b;
 667         u32 chain_noise_c;
 668         u32 chain_sig_a;
 669         u32 chain_sig_b;
 670         u32 chain_sig_c;
 671         u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
 672         u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
 673         u32 max_average_sig;
 674         u16 max_average_sig_antenna_i;
 675         u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
 676         u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
 677         u16 i = 0;
 678         u16 rxon_chnum = INITIALIZATION_VALUE;
 679         u16 stat_chnum = INITIALIZATION_VALUE;
 680         u8 rxon_band24;
 681         u8 stat_band24;
 682         u32 active_chains = 0;
 683         u8 num_tx_chains;
 684         unsigned long flags;
 685         struct statistics_rx_non_phy *rx_info = &(stat_resp->rx.general);
 686         u8 first_chain;
 687
 688         if (priv->disable_chain_noise_cal)
 689                 return;
 690
 691         data = &(priv->chain_noise_data);
 692
 693         /*
 694          * Accumulate just the first "chain_noise_num_beacons" after
 695          * the first association, then we're done forever.
 696          */
 697         if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) {
 698                 if (data->state == IWL_CHAIN_NOISE_ALIVE)
 699                         IWL_DEBUG_CALIB(priv, "Wait for noise calib reset\n");
 700                 return;
 701         }
 702
 703         spin_lock_irqsave(&priv->lock, flags);
 704         if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
 705                 IWL_DEBUG_CALIB(priv, " << Interference data unavailable\n");
 706                 spin_unlock_irqrestore(&priv->lock, flags);
 707                 return;
 708         }
 709
 710         rxon_band24 = !!(priv->staging_rxon.flags & RXON_FLG_BAND_24G_MSK);
 711         rxon_chnum = le16_to_cpu(priv->staging_rxon.channel);
 712         stat_band24 = !!(stat_resp->flag & STATISTICS_REPLY_FLG_BAND_24G_MSK);
 713         stat_chnum = le32_to_cpu(stat_resp->flag) >> 16;
 714
 715         /* Make sure we accumulate data for just the associated channel
 716          *   (even if scanning). */
 717         if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) {
 718                 IWL_DEBUG_CALIB(priv, "Stats not from chan=%d, band24=%d\n",
 719                                 rxon_chnum, rxon_band24);
 720                 spin_unlock_irqrestore(&priv->lock, flags);
 721                 return;
 722         }
 723
 724         /*
 725          *  Accumulate beacon statistics values across
 726          * "chain_noise_num_beacons"
 727          */
 728         chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
 729                                 IN_BAND_FILTER;
 730         chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
 731                                 IN_BAND_FILTER;
 732         chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
 733                                 IN_BAND_FILTER;
 734
 735         chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
 736         chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
 737         chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
 738
 739         spin_unlock_irqrestore(&priv->lock, flags);
 740
 741         data->beacon_count++;
 742
 743         data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
 744         data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
 745         data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
 746
 747         data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
 748         data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
 749         data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
 750
 751         IWL_DEBUG_CALIB(priv, "chan=%d, band24=%d, beacon=%d\n",
 752                         rxon_chnum, rxon_band24, data->beacon_count);
 753         IWL_DEBUG_CALIB(priv, "chain_sig: a %d b %d c %d\n",
 754                         chain_sig_a, chain_sig_b, chain_sig_c);
 755         IWL_DEBUG_CALIB(priv, "chain_noise: a %d b %d c %d\n",
 756                         chain_noise_a, chain_noise_b, chain_noise_c);
 757
 758         /* If this is the "chain_noise_num_beacons", determine:
 759          * 1)  Disconnected antennas (using signal strengths)
 760          * 2)  Differential gain (using silence noise) to balance receivers */
 761         if (data->beacon_count != priv->cfg->chain_noise_num_beacons)
 762                 return;
 763
 764         /* Analyze signal for disconnected antenna */
 765         average_sig[0] =
 766                 (data->chain_signal_a) / priv->cfg->chain_noise_num_beacons;
 767         average_sig[1] =
 768                 (data->chain_signal_b) / priv->cfg->chain_noise_num_beacons;
 769         average_sig[2] =
 770                 (data->chain_signal_c) / priv->cfg->chain_noise_num_beacons;
 771
 772         if (average_sig[0] >= average_sig[1]) {
 773                 max_average_sig = average_sig[0];
 774                 max_average_sig_antenna_i = 0;
 775                 active_chains = (1 << max_average_sig_antenna_i);
 776         } else {
 777                 max_average_sig = average_sig[1];
 778                 max_average_sig_antenna_i = 1;
 779                 active_chains = (1 << max_average_sig_antenna_i);
 780         }
 781
 782         if (average_sig[2] >= max_average_sig) {
 783                 max_average_sig = average_sig[2];
 784                 max_average_sig_antenna_i = 2;
 785                 active_chains = (1 << max_average_sig_antenna_i);
 786         }
 787
 788         IWL_DEBUG_CALIB(priv, "average_sig: a %d b %d c %d\n",
 789                      average_sig[0], average_sig[1], average_sig[2]);
 790         IWL_DEBUG_CALIB(priv, "max_average_sig = %d, antenna %d\n",
 791                      max_average_sig, max_average_sig_antenna_i);
 792
 793         /* Compare signal strengths for all 3 receivers. */
 794         for (i = 0; i < NUM_RX_CHAINS; i++) {
 795                 if (i != max_average_sig_antenna_i) {
 796                         s32 rssi_delta = (max_average_sig - average_sig[i]);
 797
 798                         /* If signal is very weak, compared with
 799                          * strongest, mark it as disconnected. */
 800                         if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
 801                                 data->disconn_array[i] = 1;
 802                         else
 803                                 active_chains |= (1 << i);
 804                         IWL_DEBUG_CALIB(priv, "i = %d  rssiDelta = %d  "
 805                              "disconn_array[i] = %d\n",
 806                              i, rssi_delta, data->disconn_array[i]);
 807                 }
 808         }
 809
 810         num_tx_chains = 0;
 811         for (i = 0; i < NUM_RX_CHAINS; i++) {
 812                 /* loops on all the bits of
 813                  * priv->hw_setting.valid_tx_ant */
 814                 u8 ant_msk = (1 << i);
 815                 if (!(priv->hw_params.valid_tx_ant & ant_msk))
 816                         continue;
 817
 818                 num_tx_chains++;
 819                 if (data->disconn_array[i] == 0)
 820                         /* there is a Tx antenna connected */
 821                         break;
 822                 if (num_tx_chains == priv->hw_params.tx_chains_num &&
 823                     data->disconn_array[i]) {
 824                         /*
 825                          * If all chains are disconnected
 826                          * connect the first valid tx chain
 827                          */
 828                         first_chain =
 829                                 find_first_chain(priv->cfg->valid_tx_ant);
 830                         data->disconn_array[first_chain] = 0;
 831                         active_chains |= BIT(first_chain);
 832                         IWL_DEBUG_CALIB(priv, "All Tx chains are disconnected W/A - declare %d as connected\n",
 833                                         first_chain);
 834                         break;
 835                 }
 836         }
 837
 838         /* Save for use within RXON, TX, SCAN commands, etc. */
 839         priv->chain_noise_data.active_chains = active_chains;
 840         IWL_DEBUG_CALIB(priv, "active_chains (bitwise) = 0x%x\n",
 841                         active_chains);
 842
 843         /* Analyze noise for rx balance */
 844         average_noise[0] =
 845                 ((data->chain_noise_a) / priv->cfg->chain_noise_num_beacons);
 846         average_noise[1] =
 847                 ((data->chain_noise_b) / priv->cfg->chain_noise_num_beacons);
 848         average_noise[2] =
 849                 ((data->chain_noise_c) / priv->cfg->chain_noise_num_beacons);
 850
 851         for (i = 0; i < NUM_RX_CHAINS; i++) {
 852                 if (!(data->disconn_array[i]) &&
 853                    (average_noise[i] <= min_average_noise)) {
 854                         /* This means that chain i is active and has
 855                          * lower noise values so far: */
 856                         min_average_noise = average_noise[i];
 857                         min_average_noise_antenna_i = i;
 858                 }
 859         }
 860
 861         IWL_DEBUG_CALIB(priv, "average_noise: a %d b %d c %d\n",
 862                         average_noise[0], average_noise[1],
 863                         average_noise[2]);
 864
 865         IWL_DEBUG_CALIB(priv, "min_average_noise = %d, antenna %d\n",
 866                         min_average_noise, min_average_noise_antenna_i);
 867
 868         if (priv->cfg->ops->utils->gain_computation)
 869                 priv->cfg->ops->utils->gain_computation(priv, average_noise,
 870                                 min_average_noise_antenna_i, min_average_noise,
 871                                 find_first_chain(priv->cfg->valid_rx_ant));
 872
 873         /* Some power changes may have been made during the calibration.
 874          * Update and commit the RXON
 875          */
 876         if (priv->cfg->ops->lib->update_chain_flags)
 877                 priv->cfg->ops->lib->update_chain_flags(priv);
 878
 879         data->state = IWL_CHAIN_NOISE_DONE;
 880         iwl_power_update_mode(priv, false);
 881 }
 882 EXPORT_SYMBOL(iwl_chain_noise_calibration);
 883
 884
 885 void iwl_reset_run_time_calib(struct iwl_priv *priv)
 886 {
 887         int i;
 888         memset(&(priv->sensitivity_data), 0,
 889                sizeof(struct iwl_sensitivity_data));
 890         memset(&(priv->chain_noise_data), 0,
 891                sizeof(struct iwl_chain_noise_data));
 892         for (i = 0; i < NUM_RX_CHAINS; i++)
 893                 priv->chain_noise_data.delta_gain_code[i] =
 894                                 CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
 895
 896         /* Ask for statistics now, the uCode will send notification
 897          * periodically after association */
 898         iwl_send_statistics_request(priv, CMD_ASYNC, true);
 899 }
 900 EXPORT_SYMBOL(iwl_reset_run_time_calib);
 901