drivers/net/wireless/iwlegacy/4965-calib.c

   1 /******************************************************************************
   2  *
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   6  * GPL LICENSE SUMMARY
   7  *
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  10  * This program is free software; you can redistribute it and/or modify
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  13  *
  14  * This program is distributed in the hope that it will be useful, but
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  20  * along with this program; if not, write to the Free Software
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  44  *    the documentation and/or other materials provided with the
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  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,
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  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 <linux/slab.h>
  64 #include <net/mac80211.h>
  65
  66 #include "common.h"
  67 #include "4965.h"
  68
  69 /*****************************************************************************
  70  * INIT calibrations framework
  71  *****************************************************************************/
  72
  73 struct stats_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 void il4965_calib_free_results(struct il_priv *il)
  83 {
  84         int i;
  85
  86         for (i = 0; i < IL_CALIB_MAX; i++) {
  87                 kfree(il->calib_results[i].buf);
  88                 il->calib_results[i].buf = NULL;
  89                 il->calib_results[i].buf_len = 0;
  90         }
  91 }
  92
  93 /*****************************************************************************
  94  * RUNTIME calibrations framework
  95  *****************************************************************************/
  96
  97 /* "false alarms" are signals that our DSP tries to lock onto,
  98  *   but then determines that they are either noise, or transmissions
  99  *   from a distant wireless network (also "noise", really) that get
 100  *   "stepped on" by stronger transmissions within our own network.
 101  * This algorithm attempts to set a sensitivity level that is high
 102  *   enough to receive all of our own network traffic, but not so
 103  *   high that our DSP gets too busy trying to lock onto non-network
 104  *   activity/noise. */
 105 static int il4965_sens_energy_cck(struct il_priv *il,
 106                                    u32 norm_fa,
 107                                    u32 rx_enable_time,
 108                                    struct stats_general_data *rx_info)
 109 {
 110         u32 max_nrg_cck = 0;
 111         int i = 0;
 112         u8 max_silence_rssi = 0;
 113         u32 silence_ref = 0;
 114         u8 silence_rssi_a = 0;
 115         u8 silence_rssi_b = 0;
 116         u8 silence_rssi_c = 0;
 117         u32 val;
 118
 119         /* "false_alarms" values below are cross-multiplications to assess the
 120          *   numbers of false alarms within the measured period of actual Rx
 121          *   (Rx is off when we're txing), vs the min/max expected false alarms
 122          *   (some should be expected if rx is sensitive enough) in a
 123          *   hypothetical listening period of 200 time units (TU), 204.8 msec:
 124          *
 125          * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
 126          *
 127          * */
 128         u32 false_alarms = norm_fa * 200 * 1024;
 129         u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
 130         u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
 131         struct il_sensitivity_data *data = NULL;
 132         const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
 133
 134         data = &(il->sensitivity_data);
 135
 136         data->nrg_auto_corr_silence_diff = 0;
 137
 138         /* Find max silence rssi among all 3 receivers.
 139          * This is background noise, which may include transmissions from other
 140          *    networks, measured during silence before our network's beacon */
 141         silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
 142                             ALL_BAND_FILTER) >> 8);
 143         silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
 144                             ALL_BAND_FILTER) >> 8);
 145         silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
 146                             ALL_BAND_FILTER) >> 8);
 147
 148         val = max(silence_rssi_b, silence_rssi_c);
 149         max_silence_rssi = max(silence_rssi_a, (u8) val);
 150
 151         /* Store silence rssi in 20-beacon history table */
 152         data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
 153         data->nrg_silence_idx++;
 154         if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
 155                 data->nrg_silence_idx = 0;
 156
 157         /* Find max silence rssi across 20 beacon history */
 158         for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
 159                 val = data->nrg_silence_rssi[i];
 160                 silence_ref = max(silence_ref, val);
 161         }
 162         D_CALIB("silence a %u, b %u, c %u, 20-bcn max %u\n",
 163                         silence_rssi_a, silence_rssi_b, silence_rssi_c,
 164                         silence_ref);
 165
 166         /* Find max rx energy (min value!) among all 3 receivers,
 167          *   measured during beacon frame.
 168          * Save it in 10-beacon history table. */
 169         i = data->nrg_energy_idx;
 170         val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
 171         data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
 172
 173         data->nrg_energy_idx++;
 174         if (data->nrg_energy_idx >= 10)
 175                 data->nrg_energy_idx = 0;
 176
 177         /* Find min rx energy (max value) across 10 beacon history.
 178          * This is the minimum signal level that we want to receive well.
 179          * Add backoff (margin so we don't miss slightly lower energy frames).
 180          * This establishes an upper bound (min value) for energy threshold. */
 181         max_nrg_cck = data->nrg_value[0];
 182         for (i = 1; i < 10; i++)
 183                 max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
 184         max_nrg_cck += 6;
 185
 186         D_CALIB("rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
 187                         rx_info->beacon_energy_a, rx_info->beacon_energy_b,
 188                         rx_info->beacon_energy_c, max_nrg_cck - 6);
 189
 190         /* Count number of consecutive beacons with fewer-than-desired
 191          *   false alarms. */
 192         if (false_alarms < min_false_alarms)
 193                 data->num_in_cck_no_fa++;
 194         else
 195                 data->num_in_cck_no_fa = 0;
 196         D_CALIB("consecutive bcns with few false alarms = %u\n",
 197                         data->num_in_cck_no_fa);
 198
 199         /* If we got too many false alarms this time, reduce sensitivity */
 200         if (false_alarms > max_false_alarms &&
 201             data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK) {
 202                 D_CALIB("norm FA %u > max FA %u\n",
 203                      false_alarms, max_false_alarms);
 204                 D_CALIB("... reducing sensitivity\n");
 205                 data->nrg_curr_state = IL_FA_TOO_MANY;
 206                 /* Store for "fewer than desired" on later beacon */
 207                 data->nrg_silence_ref = silence_ref;
 208
 209                 /* increase energy threshold (reduce nrg value)
 210                  *   to decrease sensitivity */
 211                 data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
 212         /* Else if we got fewer than desired, increase sensitivity */
 213         } else if (false_alarms < min_false_alarms) {
 214                 data->nrg_curr_state = IL_FA_TOO_FEW;
 215
 216                 /* Compare silence level with silence level for most recent
 217                  *   healthy number or too many false alarms */
 218                 data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
 219                                                    (s32)silence_ref;
 220
 221                 D_CALIB(
 222                          "norm FA %u < min FA %u, silence diff %d\n",
 223                          false_alarms, min_false_alarms,
 224                          data->nrg_auto_corr_silence_diff);
 225
 226                 /* Increase value to increase sensitivity, but only if:
 227                  * 1a) previous beacon did *not* have *too many* false alarms
 228                  * 1b) AND there's a significant difference in Rx levels
 229                  *      from a previous beacon with too many, or healthy # FAs
 230                  * OR 2) We've seen a lot of beacons (100) with too few
 231                  *       false alarms */
 232                 if (data->nrg_prev_state != IL_FA_TOO_MANY &&
 233                     (data->nrg_auto_corr_silence_diff > NRG_DIFF ||
 234                      data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA)) {
 235
 236                         D_CALIB("... increasing sensitivity\n");
 237                         /* Increase nrg value to increase sensitivity */
 238                         val = data->nrg_th_cck + NRG_STEP_CCK;
 239                         data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
 240                 } else {
 241                         D_CALIB(
 242                                          "... but not changing sensitivity\n");
 243                 }
 244
 245         /* Else we got a healthy number of false alarms, keep status quo */
 246         } else {
 247                 D_CALIB(" FA in safe zone\n");
 248                 data->nrg_curr_state = IL_FA_GOOD_RANGE;
 249
 250                 /* Store for use in "fewer than desired" with later beacon */
 251                 data->nrg_silence_ref = silence_ref;
 252
 253                 /* If previous beacon had too many false alarms,
 254                  *   give it some extra margin by reducing sensitivity again
 255                  *   (but don't go below measured energy of desired Rx) */
 256                 if (IL_FA_TOO_MANY == data->nrg_prev_state) {
 257                         D_CALIB("... increasing margin\n");
 258                         if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
 259                                 data->nrg_th_cck -= NRG_MARGIN;
 260                         else
 261                                 data->nrg_th_cck = max_nrg_cck;
 262                 }
 263         }
 264
 265         /* Make sure the energy threshold does not go above the measured
 266          * energy of the desired Rx signals (reduced by backoff margin),
 267          * or else we might start missing Rx frames.
 268          * Lower value is higher energy, so we use max()!
 269          */
 270         data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
 271         D_CALIB("new nrg_th_cck %u\n", data->nrg_th_cck);
 272
 273         data->nrg_prev_state = data->nrg_curr_state;
 274
 275         /* Auto-correlation CCK algorithm */
 276         if (false_alarms > min_false_alarms) {
 277
 278                 /* increase auto_corr values to decrease sensitivity
 279                  * so the DSP won't be disturbed by the noise
 280                  */
 281                 if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
 282                         data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
 283                 else {
 284                         val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
 285                         data->auto_corr_cck =
 286                                 min((u32)ranges->auto_corr_max_cck, val);
 287                 }
 288                 val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
 289                 data->auto_corr_cck_mrc =
 290                         min((u32)ranges->auto_corr_max_cck_mrc, val);
 291         } else if (false_alarms < min_false_alarms &&
 292                    (data->nrg_auto_corr_silence_diff > NRG_DIFF ||
 293                     data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA)) {
 294
 295                 /* Decrease auto_corr values to increase sensitivity */
 296                 val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
 297                 data->auto_corr_cck =
 298                         max((u32)ranges->auto_corr_min_cck, val);
 299                 val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
 300                 data->auto_corr_cck_mrc =
 301                         max((u32)ranges->auto_corr_min_cck_mrc, val);
 302         }
 303
 304         return 0;
 305 }
 306
 307
 308 static int il4965_sens_auto_corr_ofdm(struct il_priv *il,
 309                                        u32 norm_fa,
 310                                        u32 rx_enable_time)
 311 {
 312         u32 val;
 313         u32 false_alarms = norm_fa * 200 * 1024;
 314         u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
 315         u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
 316         struct il_sensitivity_data *data = NULL;
 317         const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
 318
 319         data = &(il->sensitivity_data);
 320
 321         /* If we got too many false alarms this time, reduce sensitivity */
 322         if (false_alarms > max_false_alarms) {
 323
 324                 D_CALIB("norm FA %u > max FA %u)\n",
 325                              false_alarms, max_false_alarms);
 326
 327                 val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
 328                 data->auto_corr_ofdm =
 329                         min((u32)ranges->auto_corr_max_ofdm, val);
 330
 331                 val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
 332                 data->auto_corr_ofdm_mrc =
 333                         min((u32)ranges->auto_corr_max_ofdm_mrc, val);
 334
 335                 val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
 336                 data->auto_corr_ofdm_x1 =
 337                         min((u32)ranges->auto_corr_max_ofdm_x1, val);
 338
 339                 val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
 340                 data->auto_corr_ofdm_mrc_x1 =
 341                         min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
 342         }
 343
 344         /* Else if we got fewer than desired, increase sensitivity */
 345         else if (false_alarms < min_false_alarms) {
 346
 347                 D_CALIB("norm FA %u < min FA %u\n",
 348                              false_alarms, min_false_alarms);
 349
 350                 val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
 351                 data->auto_corr_ofdm =
 352                         max((u32)ranges->auto_corr_min_ofdm, val);
 353
 354                 val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
 355                 data->auto_corr_ofdm_mrc =
 356                         max((u32)ranges->auto_corr_min_ofdm_mrc, val);
 357
 358                 val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
 359                 data->auto_corr_ofdm_x1 =
 360                         max((u32)ranges->auto_corr_min_ofdm_x1, val);
 361
 362                 val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
 363                 data->auto_corr_ofdm_mrc_x1 =
 364                         max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
 365         } else {
 366                 D_CALIB("min FA %u < norm FA %u < max FA %u OK\n",
 367                          min_false_alarms, false_alarms, max_false_alarms);
 368         }
 369         return 0;
 370 }
 371
 372 static void il4965_prepare_legacy_sensitivity_tbl(struct il_priv *il,
 373                                 struct il_sensitivity_data *data,
 374                                 __le16 *tbl)
 375 {
 376         tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_IDX] =
 377                                 cpu_to_le16((u16)data->auto_corr_ofdm);
 378         tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_IDX] =
 379                                 cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
 380         tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_IDX] =
 381                                 cpu_to_le16((u16)data->auto_corr_ofdm_x1);
 382         tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_IDX] =
 383                                 cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);
 384
 385         tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_IDX] =
 386                                 cpu_to_le16((u16)data->auto_corr_cck);
 387         tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_IDX] =
 388                                 cpu_to_le16((u16)data->auto_corr_cck_mrc);
 389
 390         tbl[HD_MIN_ENERGY_CCK_DET_IDX] =
 391                                 cpu_to_le16((u16)data->nrg_th_cck);
 392         tbl[HD_MIN_ENERGY_OFDM_DET_IDX] =
 393                                 cpu_to_le16((u16)data->nrg_th_ofdm);
 394
 395         tbl[HD_BARKER_CORR_TH_ADD_MIN_IDX] =
 396                                 cpu_to_le16(data->barker_corr_th_min);
 397         tbl[HD_BARKER_CORR_TH_ADD_MIN_MRC_IDX] =
 398                                 cpu_to_le16(data->barker_corr_th_min_mrc);
 399         tbl[HD_OFDM_ENERGY_TH_IN_IDX] =
 400                                 cpu_to_le16(data->nrg_th_cca);
 401
 402         D_CALIB("ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
 403                         data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
 404                         data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
 405                         data->nrg_th_ofdm);
 406
 407         D_CALIB("cck: ac %u mrc %u thresh %u\n",
 408                         data->auto_corr_cck, data->auto_corr_cck_mrc,
 409                         data->nrg_th_cck);
 410 }
 411
 412 /* Prepare a C_SENSITIVITY, send to uCode if values have changed */
 413 static int il4965_sensitivity_write(struct il_priv *il)
 414 {
 415         struct il_sensitivity_cmd cmd;
 416         struct il_sensitivity_data *data = NULL;
 417         struct il_host_cmd cmd_out = {
 418                 .id = C_SENSITIVITY,
 419                 .len = sizeof(struct il_sensitivity_cmd),
 420                 .flags = CMD_ASYNC,
 421                 .data = &cmd,
 422         };
 423
 424         data = &(il->sensitivity_data);
 425
 426         memset(&cmd, 0, sizeof(cmd));
 427
 428         il4965_prepare_legacy_sensitivity_tbl(il, data, &cmd.table[0]);
 429
 430         /* Update uCode's "work" table, and copy it to DSP */
 431         cmd.control = C_SENSITIVITY_CONTROL_WORK_TBL;
 432
 433         /* Don't send command to uCode if nothing has changed */
 434         if (!memcmp(&cmd.table[0], &(il->sensitivity_tbl[0]),
 435                     sizeof(u16)*HD_TBL_SIZE)) {
 436                 D_CALIB("No change in C_SENSITIVITY\n");
 437                 return 0;
 438         }
 439
 440         /* Copy table for comparison next time */
 441         memcpy(&(il->sensitivity_tbl[0]), &(cmd.table[0]),
 442                sizeof(u16)*HD_TBL_SIZE);
 443
 444         return il_send_cmd(il, &cmd_out);
 445 }
 446
 447 void il4965_init_sensitivity(struct il_priv *il)
 448 {
 449         int ret = 0;
 450         int i;
 451         struct il_sensitivity_data *data = NULL;
 452         const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
 453
 454         if (il->disable_sens_cal)
 455                 return;
 456
 457         D_CALIB("Start il4965_init_sensitivity\n");
 458
 459         /* Clear driver's sensitivity algo data */
 460         data = &(il->sensitivity_data);
 461
 462         if (ranges == NULL)
 463                 return;
 464
 465         memset(data, 0, sizeof(struct il_sensitivity_data));
 466
 467         data->num_in_cck_no_fa = 0;
 468         data->nrg_curr_state = IL_FA_TOO_MANY;
 469         data->nrg_prev_state = IL_FA_TOO_MANY;
 470         data->nrg_silence_ref = 0;
 471         data->nrg_silence_idx = 0;
 472         data->nrg_energy_idx = 0;
 473
 474         for (i = 0; i < 10; i++)
 475                 data->nrg_value[i] = 0;
 476
 477         for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
 478                 data->nrg_silence_rssi[i] = 0;
 479
 480         data->auto_corr_ofdm =  ranges->auto_corr_min_ofdm;
 481         data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
 482         data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
 483         data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
 484         data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
 485         data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
 486         data->nrg_th_cck = ranges->nrg_th_cck;
 487         data->nrg_th_ofdm = ranges->nrg_th_ofdm;
 488         data->barker_corr_th_min = ranges->barker_corr_th_min;
 489         data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
 490         data->nrg_th_cca = ranges->nrg_th_cca;
 491
 492         data->last_bad_plcp_cnt_ofdm = 0;
 493         data->last_fa_cnt_ofdm = 0;
 494         data->last_bad_plcp_cnt_cck = 0;
 495         data->last_fa_cnt_cck = 0;
 496
 497         ret |= il4965_sensitivity_write(il);
 498         D_CALIB("<<return 0x%X\n", ret);
 499 }
 500
 501 void il4965_sensitivity_calibration(struct il_priv *il, void *resp)
 502 {
 503         u32 rx_enable_time;
 504         u32 fa_cck;
 505         u32 fa_ofdm;
 506         u32 bad_plcp_cck;
 507         u32 bad_plcp_ofdm;
 508         u32 norm_fa_ofdm;
 509         u32 norm_fa_cck;
 510         struct il_sensitivity_data *data = NULL;
 511         struct stats_rx_non_phy *rx_info;
 512         struct stats_rx_phy *ofdm, *cck;
 513         unsigned long flags;
 514         struct stats_general_data statis;
 515
 516         if (il->disable_sens_cal)
 517                 return;
 518
 519         data = &(il->sensitivity_data);
 520
 521         if (!il_is_any_associated(il)) {
 522                 D_CALIB("<< - not associated\n");
 523                 return;
 524         }
 525
 526         spin_lock_irqsave(&il->lock, flags);
 527
 528         rx_info = &(((struct il_notif_stats *)resp)->rx.general);
 529         ofdm = &(((struct il_notif_stats *)resp)->rx.ofdm);
 530         cck = &(((struct il_notif_stats *)resp)->rx.cck);
 531
 532         if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
 533                 D_CALIB("<< invalid data.\n");
 534                 spin_unlock_irqrestore(&il->lock, flags);
 535                 return;
 536         }
 537
 538         /* Extract Statistics: */
 539         rx_enable_time = le32_to_cpu(rx_info->channel_load);
 540         fa_cck = le32_to_cpu(cck->false_alarm_cnt);
 541         fa_ofdm = le32_to_cpu(ofdm->false_alarm_cnt);
 542         bad_plcp_cck = le32_to_cpu(cck->plcp_err);
 543         bad_plcp_ofdm = le32_to_cpu(ofdm->plcp_err);
 544
 545         statis.beacon_silence_rssi_a =
 546                         le32_to_cpu(rx_info->beacon_silence_rssi_a);
 547         statis.beacon_silence_rssi_b =
 548                         le32_to_cpu(rx_info->beacon_silence_rssi_b);
 549         statis.beacon_silence_rssi_c =
 550                         le32_to_cpu(rx_info->beacon_silence_rssi_c);
 551         statis.beacon_energy_a =
 552                         le32_to_cpu(rx_info->beacon_energy_a);
 553         statis.beacon_energy_b =
 554                         le32_to_cpu(rx_info->beacon_energy_b);
 555         statis.beacon_energy_c =
 556                         le32_to_cpu(rx_info->beacon_energy_c);
 557
 558         spin_unlock_irqrestore(&il->lock, flags);
 559
 560         D_CALIB("rx_enable_time = %u usecs\n", rx_enable_time);
 561
 562         if (!rx_enable_time) {
 563                 D_CALIB("<< RX Enable Time == 0!\n");
 564                 return;
 565         }
 566
 567         /* These stats increase monotonically, and do not reset
 568          *   at each beacon.  Calculate difference from last value, or just
 569          *   use the new stats value if it has reset or wrapped around. */
 570         if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
 571                 data->last_bad_plcp_cnt_cck = bad_plcp_cck;
 572         else {
 573                 bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
 574                 data->last_bad_plcp_cnt_cck += bad_plcp_cck;
 575         }
 576
 577         if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
 578                 data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
 579         else {
 580                 bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
 581                 data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
 582         }
 583
 584         if (data->last_fa_cnt_ofdm > fa_ofdm)
 585                 data->last_fa_cnt_ofdm = fa_ofdm;
 586         else {
 587                 fa_ofdm -= data->last_fa_cnt_ofdm;
 588                 data->last_fa_cnt_ofdm += fa_ofdm;
 589         }
 590
 591         if (data->last_fa_cnt_cck > fa_cck)
 592                 data->last_fa_cnt_cck = fa_cck;
 593         else {
 594                 fa_cck -= data->last_fa_cnt_cck;
 595                 data->last_fa_cnt_cck += fa_cck;
 596         }
 597
 598         /* Total aborted signal locks */
 599         norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
 600         norm_fa_cck = fa_cck + bad_plcp_cck;
 601
 602         D_CALIB(
 603                          "cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
 604                         bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
 605
 606         il4965_sens_auto_corr_ofdm(il, norm_fa_ofdm, rx_enable_time);
 607         il4965_sens_energy_cck(il, norm_fa_cck, rx_enable_time, &statis);
 608
 609         il4965_sensitivity_write(il);
 610 }
 611
 612 static inline u8 il4965_find_first_chain(u8 mask)
 613 {
 614         if (mask & ANT_A)
 615                 return CHAIN_A;
 616         if (mask & ANT_B)
 617                 return CHAIN_B;
 618         return CHAIN_C;
 619 }
 620
 621 /**
 622  * Run disconnected antenna algorithm to find out which antennas are
 623  * disconnected.
 624  */
 625 static void
 626 il4965_find_disconn_antenna(struct il_priv *il, u32* average_sig,
 627                                      struct il_chain_noise_data *data)
 628 {
 629         u32 active_chains = 0;
 630         u32 max_average_sig;
 631         u16 max_average_sig_antenna_i;
 632         u8 num_tx_chains;
 633         u8 first_chain;
 634         u16 i = 0;
 635
 636         average_sig[0] = data->chain_signal_a /
 637                          il->cfg->base_params->chain_noise_num_beacons;
 638         average_sig[1] = data->chain_signal_b /
 639                          il->cfg->base_params->chain_noise_num_beacons;
 640         average_sig[2] = data->chain_signal_c /
 641                          il->cfg->base_params->chain_noise_num_beacons;
 642
 643         if (average_sig[0] >= average_sig[1]) {
 644                 max_average_sig = average_sig[0];
 645                 max_average_sig_antenna_i = 0;
 646                 active_chains = (1 << max_average_sig_antenna_i);
 647         } else {
 648                 max_average_sig = average_sig[1];
 649                 max_average_sig_antenna_i = 1;
 650                 active_chains = (1 << max_average_sig_antenna_i);
 651         }
 652
 653         if (average_sig[2] >= max_average_sig) {
 654                 max_average_sig = average_sig[2];
 655                 max_average_sig_antenna_i = 2;
 656                 active_chains = (1 << max_average_sig_antenna_i);
 657         }
 658
 659         D_CALIB("average_sig: a %d b %d c %d\n",
 660                      average_sig[0], average_sig[1], average_sig[2]);
 661         D_CALIB("max_average_sig = %d, antenna %d\n",
 662                      max_average_sig, max_average_sig_antenna_i);
 663
 664         /* Compare signal strengths for all 3 receivers. */
 665         for (i = 0; i < NUM_RX_CHAINS; i++) {
 666                 if (i != max_average_sig_antenna_i) {
 667                         s32 rssi_delta = (max_average_sig - average_sig[i]);
 668
 669                         /* If signal is very weak, compared with
 670                          * strongest, mark it as disconnected. */
 671                         if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
 672                                 data->disconn_array[i] = 1;
 673                         else
 674                                 active_chains |= (1 << i);
 675                         D_CALIB("i = %d  rssiDelta = %d  "
 676                              "disconn_array[i] = %d\n",
 677                              i, rssi_delta, data->disconn_array[i]);
 678                 }
 679         }
 680
 681         /*
 682          * The above algorithm sometimes fails when the ucode
 683          * reports 0 for all chains. It's not clear why that
 684          * happens to start with, but it is then causing trouble
 685          * because this can make us enable more chains than the
 686          * hardware really has.
 687          *
 688          * To be safe, simply mask out any chains that we know
 689          * are not on the device.
 690          */
 691         active_chains &= il->hw_params.valid_rx_ant;
 692
 693         num_tx_chains = 0;
 694         for (i = 0; i < NUM_RX_CHAINS; i++) {
 695                 /* loops on all the bits of
 696                  * il->hw_setting.valid_tx_ant */
 697                 u8 ant_msk = (1 << i);
 698                 if (!(il->hw_params.valid_tx_ant & ant_msk))
 699                         continue;
 700
 701                 num_tx_chains++;
 702                 if (data->disconn_array[i] == 0)
 703                         /* there is a Tx antenna connected */
 704                         break;
 705                 if (num_tx_chains == il->hw_params.tx_chains_num &&
 706                     data->disconn_array[i]) {
 707                         /*
 708                          * If all chains are disconnected
 709                          * connect the first valid tx chain
 710                          */
 711                         first_chain =
 712                         il4965_find_first_chain(il->cfg->valid_tx_ant);
 713                         data->disconn_array[first_chain] = 0;
 714                         active_chains |= BIT(first_chain);
 715                         D_CALIB(
 716                                         "All Tx chains are disconnected W/A - declare %d as connected\n",
 717                                         first_chain);
 718                         break;
 719                 }
 720         }
 721
 722         if (active_chains != il->hw_params.valid_rx_ant &&
 723             active_chains != il->chain_noise_data.active_chains)
 724                 D_CALIB(
 725                                 "Detected that not all antennas are connected! "
 726                                 "Connected: %#x, valid: %#x.\n",
 727                                 active_chains, il->hw_params.valid_rx_ant);
 728
 729         /* Save for use within RXON, TX, SCAN commands, etc. */
 730         data->active_chains = active_chains;
 731         D_CALIB("active_chains (bitwise) = 0x%x\n",
 732                         active_chains);
 733 }
 734
 735 static void il4965_gain_computation(struct il_priv *il,
 736                 u32 *average_noise,
 737                 u16 min_average_noise_antenna_i,
 738                 u32 min_average_noise,
 739                 u8 default_chain)
 740 {
 741         int i, ret;
 742         struct il_chain_noise_data *data = &il->chain_noise_data;
 743
 744         data->delta_gain_code[min_average_noise_antenna_i] = 0;
 745
 746         for (i = default_chain; i < NUM_RX_CHAINS; i++) {
 747                 s32 delta_g = 0;
 748
 749                 if (!data->disconn_array[i] &&
 750                     data->delta_gain_code[i] == CHAIN_NOISE_DELTA_GAIN_INIT_VAL) {
 751                         delta_g = average_noise[i] - min_average_noise;
 752                         data->delta_gain_code[i] = (u8)((delta_g * 10) / 15);
 753                         data->delta_gain_code[i] =
 754                                 min(data->delta_gain_code[i],
 755                                 (u8) CHAIN_NOISE_MAX_DELTA_GAIN_CODE);
 756
 757                         data->delta_gain_code[i] =
 758                                 (data->delta_gain_code[i] | (1 << 2));
 759                 } else {
 760                         data->delta_gain_code[i] = 0;
 761                 }
 762         }
 763         D_CALIB("delta_gain_codes: a %d b %d c %d\n",
 764                      data->delta_gain_code[0],
 765                      data->delta_gain_code[1],
 766                      data->delta_gain_code[2]);
 767
 768         /* Differential gain gets sent to uCode only once */
 769         if (!data->radio_write) {
 770                 struct il_calib_diff_gain_cmd cmd;
 771                 data->radio_write = 1;
 772
 773                 memset(&cmd, 0, sizeof(cmd));
 774                 cmd.hdr.op_code = IL_PHY_CALIBRATE_DIFF_GAIN_CMD;
 775                 cmd.diff_gain_a = data->delta_gain_code[0];
 776                 cmd.diff_gain_b = data->delta_gain_code[1];
 777                 cmd.diff_gain_c = data->delta_gain_code[2];
 778                 ret = il_send_cmd_pdu(il, C_PHY_CALIBRATION,
 779                                       sizeof(cmd), &cmd);
 780                 if (ret)
 781                         D_CALIB("fail sending cmd "
 782                                      "C_PHY_CALIBRATION\n");
 783
 784                 /* TODO we might want recalculate
 785                  * rx_chain in rxon cmd */
 786
 787                 /* Mark so we run this algo only once! */
 788                 data->state = IL_CHAIN_NOISE_CALIBRATED;
 789         }
 790 }
 791
 792
 793
 794 /*
 795  * Accumulate 16 beacons of signal and noise stats for each of
 796  *   3 receivers/antennas/rx-chains, then figure out:
 797  * 1)  Which antennas are connected.
 798  * 2)  Differential rx gain settings to balance the 3 receivers.
 799  */
 800 void il4965_chain_noise_calibration(struct il_priv *il, void *stat_resp)
 801 {
 802         struct il_chain_noise_data *data = NULL;
 803
 804         u32 chain_noise_a;
 805         u32 chain_noise_b;
 806         u32 chain_noise_c;
 807         u32 chain_sig_a;
 808         u32 chain_sig_b;
 809         u32 chain_sig_c;
 810         u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
 811         u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
 812         u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
 813         u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
 814         u16 i = 0;
 815         u16 rxon_chnum = INITIALIZATION_VALUE;
 816         u16 stat_chnum = INITIALIZATION_VALUE;
 817         u8 rxon_band24;
 818         u8 stat_band24;
 819         unsigned long flags;
 820         struct stats_rx_non_phy *rx_info;
 821
 822         struct il_rxon_context *ctx = &il->ctx;
 823
 824         if (il->disable_chain_noise_cal)
 825                 return;
 826
 827         data = &(il->chain_noise_data);
 828
 829         /*
 830          * Accumulate just the first "chain_noise_num_beacons" after
 831          * the first association, then we're done forever.
 832          */
 833         if (data->state != IL_CHAIN_NOISE_ACCUMULATE) {
 834                 if (data->state == IL_CHAIN_NOISE_ALIVE)
 835                         D_CALIB("Wait for noise calib reset\n");
 836                 return;
 837         }
 838
 839         spin_lock_irqsave(&il->lock, flags);
 840
 841         rx_info = &(((struct il_notif_stats *)stat_resp)->
 842                       rx.general);
 843
 844         if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
 845                 D_CALIB(" << Interference data unavailable\n");
 846                 spin_unlock_irqrestore(&il->lock, flags);
 847                 return;
 848         }
 849
 850         rxon_band24 = !!(ctx->staging.flags & RXON_FLG_BAND_24G_MSK);
 851         rxon_chnum = le16_to_cpu(ctx->staging.channel);
 852
 853         stat_band24 = !!(((struct il_notif_stats *)
 854                          stat_resp)->flag &
 855                          STATS_REPLY_FLG_BAND_24G_MSK);
 856         stat_chnum = le32_to_cpu(((struct il_notif_stats *)
 857                                  stat_resp)->flag) >> 16;
 858
 859         /* Make sure we accumulate data for just the associated channel
 860          *   (even if scanning). */
 861         if (rxon_chnum != stat_chnum || rxon_band24 != stat_band24) {
 862                 D_CALIB("Stats not from chan=%d, band24=%d\n",
 863                                 rxon_chnum, rxon_band24);
 864                 spin_unlock_irqrestore(&il->lock, flags);
 865                 return;
 866         }
 867
 868         /*
 869          *  Accumulate beacon stats values across
 870          * "chain_noise_num_beacons"
 871          */
 872         chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
 873                                 IN_BAND_FILTER;
 874         chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
 875                                 IN_BAND_FILTER;
 876         chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
 877                                 IN_BAND_FILTER;
 878
 879         chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
 880         chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
 881         chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
 882
 883         spin_unlock_irqrestore(&il->lock, flags);
 884
 885         data->beacon_count++;
 886
 887         data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
 888         data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
 889         data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
 890
 891         data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
 892         data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
 893         data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
 894
 895         D_CALIB("chan=%d, band24=%d, beacon=%d\n",
 896                         rxon_chnum, rxon_band24, data->beacon_count);
 897         D_CALIB("chain_sig: a %d b %d c %d\n",
 898                         chain_sig_a, chain_sig_b, chain_sig_c);
 899         D_CALIB("chain_noise: a %d b %d c %d\n",
 900                         chain_noise_a, chain_noise_b, chain_noise_c);
 901
 902         /* If this is the "chain_noise_num_beacons", determine:
 903          * 1)  Disconnected antennas (using signal strengths)
 904          * 2)  Differential gain (using silence noise) to balance receivers */
 905         if (data->beacon_count !=
 906                 il->cfg->base_params->chain_noise_num_beacons)
 907                 return;
 908
 909         /* Analyze signal for disconnected antenna */
 910         il4965_find_disconn_antenna(il, average_sig, data);
 911
 912         /* Analyze noise for rx balance */
 913         average_noise[0] = data->chain_noise_a /
 914                            il->cfg->base_params->chain_noise_num_beacons;
 915         average_noise[1] = data->chain_noise_b /
 916                            il->cfg->base_params->chain_noise_num_beacons;
 917         average_noise[2] = data->chain_noise_c /
 918                            il->cfg->base_params->chain_noise_num_beacons;
 919
 920         for (i = 0; i < NUM_RX_CHAINS; i++) {
 921                 if (!data->disconn_array[i] &&
 922                     average_noise[i] <= min_average_noise) {
 923                         /* This means that chain i is active and has
 924                          * lower noise values so far: */
 925                         min_average_noise = average_noise[i];
 926                         min_average_noise_antenna_i = i;
 927                 }
 928         }
 929
 930         D_CALIB("average_noise: a %d b %d c %d\n",
 931                         average_noise[0], average_noise[1],
 932                         average_noise[2]);
 933
 934         D_CALIB("min_average_noise = %d, antenna %d\n",
 935                         min_average_noise, min_average_noise_antenna_i);
 936
 937         il4965_gain_computation(il, average_noise,
 938                         min_average_noise_antenna_i, min_average_noise,
 939                         il4965_find_first_chain(il->cfg->valid_rx_ant));
 940
 941         /* Some power changes may have been made during the calibration.
 942          * Update and commit the RXON
 943          */
 944         if (il->cfg->ops->lib->update_chain_flags)
 945                 il->cfg->ops->lib->update_chain_flags(il);
 946
 947         data->state = IL_CHAIN_NOISE_DONE;
 948         il_power_update_mode(il, false);
 949 }
 950
 951 void il4965_reset_run_time_calib(struct il_priv *il)
 952 {
 953         int i;
 954         memset(&(il->sensitivity_data), 0,
 955                sizeof(struct il_sensitivity_data));
 956         memset(&(il->chain_noise_data), 0,
 957                sizeof(struct il_chain_noise_data));
 958         for (i = 0; i < NUM_RX_CHAINS; i++)
 959                 il->chain_noise_data.delta_gain_code[i] =
 960                                 CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
 961
 962         /* Ask for stats now, the uCode will send notification
 963          * periodically after association */
 964         il_send_stats_request(il, CMD_ASYNC, true);
 965 }