SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/net/wireless/iwlwifi/iwl-agn-rs.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2005 - 2010 Intel Corporation. All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  * Contact Information:
  22  *  Intel Linux Wireless <ilw@linux.intel.com>
  23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  24  *
  25  *****************************************************************************/
  26 #include <linux/kernel.h>
  27 #include <linux/init.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/wireless.h>
  30 #include <net/mac80211.h>
  31
  32 #include <linux/netdevice.h>
  33 #include <linux/etherdevice.h>
  34 #include <linux/delay.h>
  35
  36 #include <linux/workqueue.h>
  37
  38 #include "iwl-dev.h"
  39 #include "iwl-sta.h"
  40 #include "iwl-core.h"
  41
  42 #define RS_NAME "iwl-agn-rs"
  43
  44 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
  45 #define IWL_NUMBER_TRY      1
  46 #define IWL_HT_NUMBER_TRY   3
  47
  48 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
  49 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
  50 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
  51
  52 /* max allowed rate miss before sync LQ cmd */
  53 #define IWL_MISSED_RATE_MAX             15
  54 /* max time to accum history 2 seconds */
  55 #define IWL_RATE_SCALE_FLUSH_INTVL   (3*HZ)
  56
  57 static u8 rs_ht_to_legacy[] = {
  58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  60         IWL_RATE_6M_INDEX,
  61         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
  62         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
  63         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
  64         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
  65 };
  66
  67 static const u8 ant_toggle_lookup[] = {
  68         /*ANT_NONE -> */ ANT_NONE,
  69         /*ANT_A    -> */ ANT_B,
  70         /*ANT_B    -> */ ANT_C,
  71         /*ANT_AB   -> */ ANT_BC,
  72         /*ANT_C    -> */ ANT_A,
  73         /*ANT_AC   -> */ ANT_AB,
  74         /*ANT_BC   -> */ ANT_AC,
  75         /*ANT_ABC  -> */ ANT_ABC,
  76 };
  77
  78 static void rs_rate_scale_perform(struct iwl_priv *priv,
  79                                    struct sk_buff *skb,
  80                                    struct ieee80211_sta *sta,
  81                                    struct iwl_lq_sta *lq_sta);
  82 static void rs_fill_link_cmd(struct iwl_priv *priv,
  83                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
  84
  85
  86 #ifdef CONFIG_MAC80211_DEBUGFS
  87 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
  88                              u32 *rate_n_flags, int index);
  89 #else
  90 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
  91                              u32 *rate_n_flags, int index)
  92 {}
  93 #endif
  94
  95 /**
  96  * The following tables contain the expected throughput metrics for all rates
  97  *
  98  *      1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
  99  *
 100  * where invalid entries are zeros.
 101  *
 102  * CCK rates are only valid in legacy table and will only be used in G
 103  * (2.4 GHz) band.
 104  */
 105
 106 static s32 expected_tpt_legacy[IWL_RATE_COUNT] = {
 107         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 0
 108 };
 109
 110 static s32 expected_tpt_siso20MHz[4][IWL_RATE_COUNT] = {
 111         {0, 0, 0, 0, 42, 0,  76, 102, 124, 158, 183, 193, 202}, /* Norm */
 112         {0, 0, 0, 0, 46, 0,  82, 110, 132, 167, 192, 202, 210}, /* SGI */
 113         {0, 0, 0, 0, 48, 0,  93, 135, 176, 251, 319, 351, 381}, /* AGG */
 114         {0, 0, 0, 0, 53, 0, 102, 149, 193, 275, 348, 381, 413}, /* AGG+SGI */
 115 };
 116
 117 static s32 expected_tpt_siso40MHz[4][IWL_RATE_COUNT] = {
 118         {0, 0, 0, 0,  77, 0, 127, 160, 184, 220, 242, 250, 257}, /* Norm */
 119         {0, 0, 0, 0,  83, 0, 135, 169, 193, 229, 250, 257, 264}, /* SGI */
 120         {0, 0, 0, 0,  96, 0, 182, 259, 328, 451, 553, 598, 640}, /* AGG */
 121         {0, 0, 0, 0, 106, 0, 199, 282, 357, 487, 593, 640, 683}, /* AGG+SGI */
 122 };
 123
 124 static s32 expected_tpt_mimo2_20MHz[4][IWL_RATE_COUNT] = {
 125         {0, 0, 0, 0,  74, 0, 123, 155, 179, 213, 235, 243, 250}, /* Norm */
 126         {0, 0, 0, 0,  81, 0, 131, 164, 187, 221, 242, 250, 256}, /* SGI */
 127         {0, 0, 0, 0,  92, 0, 175, 250, 317, 436, 534, 578, 619}, /* AGG */
 128         {0, 0, 0, 0, 102, 0, 192, 273, 344, 470, 573, 619, 660}, /* AGG+SGI*/
 129 };
 130
 131 static s32 expected_tpt_mimo2_40MHz[4][IWL_RATE_COUNT] = {
 132         {0, 0, 0, 0, 123, 0, 182, 214, 235, 264, 279, 285, 289}, /* Norm */
 133         {0, 0, 0, 0, 131, 0, 191, 222, 242, 270, 284, 289, 293}, /* SGI */
 134         {0, 0, 0, 0, 180, 0, 327, 446, 545, 708, 828, 878, 922}, /* AGG */
 135         {0, 0, 0, 0, 197, 0, 355, 481, 584, 752, 872, 922, 966}, /* AGG+SGI */
 136 };
 137
 138 static s32 expected_tpt_mimo3_20MHz[4][IWL_RATE_COUNT] = {
 139         {0, 0, 0, 0,  99, 0, 153, 186, 208, 239, 256, 263, 268}, /* Norm */
 140         {0, 0, 0, 0, 106, 0, 162, 194, 215, 246, 262, 268, 273}, /* SGI */
 141         {0, 0, 0, 0, 134, 0, 249, 346, 431, 574, 685, 732, 775}, /* AGG */
 142         {0, 0, 0, 0, 148, 0, 272, 376, 465, 614, 727, 775, 818}, /* AGG+SGI */
 143 };
 144
 145 static s32 expected_tpt_mimo3_40MHz[4][IWL_RATE_COUNT] = {
 146         {0, 0, 0, 0, 152, 0, 211, 239, 255, 279,  290,  294,  297}, /* Norm */
 147         {0, 0, 0, 0, 160, 0, 219, 245, 261, 284,  294,  297,  300}, /* SGI */
 148         {0, 0, 0, 0, 254, 0, 443, 584, 695, 868,  984, 1030, 1070}, /* AGG */
 149         {0, 0, 0, 0, 277, 0, 478, 624, 737, 911, 1026, 1070, 1109}, /* AGG+SGI */
 150 };
 151
 152 /* mbps, mcs */
 153 static const struct iwl_rate_mcs_info iwl_rate_mcs[IWL_RATE_COUNT] = {
 154         {  "1", "BPSK DSSS"},
 155         {  "2", "QPSK DSSS"},
 156         {"5.5", "BPSK CCK"},
 157         { "11", "QPSK CCK"},
 158         {  "6", "BPSK 1/2"},
 159         {  "9", "BPSK 1/2"},
 160         { "12", "QPSK 1/2"},
 161         { "18", "QPSK 3/4"},
 162         { "24", "16QAM 1/2"},
 163         { "36", "16QAM 3/4"},
 164         { "48", "64QAM 2/3"},
 165         { "54", "64QAM 3/4"},
 166         { "60", "64QAM 5/6"},
 167 };
 168
 169 #define MCS_INDEX_PER_STREAM    (8)
 170
 171 static inline u8 rs_extract_rate(u32 rate_n_flags)
 172 {
 173         return (u8)(rate_n_flags & 0xFF);
 174 }
 175
 176 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
 177 {
 178         window->data = 0;
 179         window->success_counter = 0;
 180         window->success_ratio = IWL_INVALID_VALUE;
 181         window->counter = 0;
 182         window->average_tpt = IWL_INVALID_VALUE;
 183         window->stamp = 0;
 184 }
 185
 186 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
 187 {
 188         return (ant_type & valid_antenna) == ant_type;
 189 }
 190
 191 /*
 192  *      removes the old data from the statistics. All data that is older than
 193  *      TID_MAX_TIME_DIFF, will be deleted.
 194  */
 195 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
 196 {
 197         /* The oldest age we want to keep */
 198         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
 199
 200         while (tl->queue_count &&
 201                (tl->time_stamp < oldest_time)) {
 202                 tl->total -= tl->packet_count[tl->head];
 203                 tl->packet_count[tl->head] = 0;
 204                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
 205                 tl->queue_count--;
 206                 tl->head++;
 207                 if (tl->head >= TID_QUEUE_MAX_SIZE)
 208                         tl->head = 0;
 209         }
 210 }
 211
 212 /*
 213  *      increment traffic load value for tid and also remove
 214  *      any old values if passed the certain time period
 215  */
 216 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
 217                            struct ieee80211_hdr *hdr)
 218 {
 219         u32 curr_time = jiffies_to_msecs(jiffies);
 220         u32 time_diff;
 221         s32 index;
 222         struct iwl_traffic_load *tl = NULL;
 223         u8 tid;
 224
 225         if (ieee80211_is_data_qos(hdr->frame_control)) {
 226                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 227                 tid = qc[0] & 0xf;
 228         } else
 229                 return MAX_TID_COUNT;
 230
 231         if (unlikely(tid >= TID_MAX_LOAD_COUNT))
 232                 return MAX_TID_COUNT;
 233
 234         tl = &lq_data->load[tid];
 235
 236         curr_time -= curr_time % TID_ROUND_VALUE;
 237
 238         /* Happens only for the first packet. Initialize the data */
 239         if (!(tl->queue_count)) {
 240                 tl->total = 1;
 241                 tl->time_stamp = curr_time;
 242                 tl->queue_count = 1;
 243                 tl->head = 0;
 244                 tl->packet_count[0] = 1;
 245                 return MAX_TID_COUNT;
 246         }
 247
 248         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 249         index = time_diff / TID_QUEUE_CELL_SPACING;
 250
 251         /* The history is too long: remove data that is older than */
 252         /* TID_MAX_TIME_DIFF */
 253         if (index >= TID_QUEUE_MAX_SIZE)
 254                 rs_tl_rm_old_stats(tl, curr_time);
 255
 256         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
 257         tl->packet_count[index] = tl->packet_count[index] + 1;
 258         tl->total = tl->total + 1;
 259
 260         if ((index + 1) > tl->queue_count)
 261                 tl->queue_count = index + 1;
 262
 263         return tid;
 264 }
 265
 266 /*
 267         get the traffic load value for tid
 268 */
 269 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
 270 {
 271         u32 curr_time = jiffies_to_msecs(jiffies);
 272         u32 time_diff;
 273         s32 index;
 274         struct iwl_traffic_load *tl = NULL;
 275
 276         if (tid >= TID_MAX_LOAD_COUNT)
 277                 return 0;
 278
 279         tl = &(lq_data->load[tid]);
 280
 281         curr_time -= curr_time % TID_ROUND_VALUE;
 282
 283         if (!(tl->queue_count))
 284                 return 0;
 285
 286         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 287         index = time_diff / TID_QUEUE_CELL_SPACING;
 288
 289         /* The history is too long: remove data that is older than */
 290         /* TID_MAX_TIME_DIFF */
 291         if (index >= TID_QUEUE_MAX_SIZE)
 292                 rs_tl_rm_old_stats(tl, curr_time);
 293
 294         return tl->total;
 295 }
 296
 297 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
 298                                       struct iwl_lq_sta *lq_data, u8 tid,
 299                                       struct ieee80211_sta *sta)
 300 {
 301         int ret;
 302
 303         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
 304                 IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n",
 305                                 sta->addr, tid);
 306                 ret = ieee80211_start_tx_ba_session(sta, tid);
 307                 if (ret == -EAGAIN) {
 308                         /*
 309                          * driver and mac80211 is out of sync
 310                          * this might be cause by reloading firmware
 311                          * stop the tx ba session here
 312                          */
 313                         IWL_DEBUG_HT(priv, "Fail start Tx agg on tid: %d\n",
 314                                 tid);
 315                         ret = ieee80211_stop_tx_ba_session(sta, tid,
 316                                                 WLAN_BACK_INITIATOR);
 317                 }
 318         }
 319 }
 320
 321 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
 322                               struct iwl_lq_sta *lq_data,
 323                               struct ieee80211_sta *sta)
 324 {
 325         if ((tid < TID_MAX_LOAD_COUNT))
 326                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 327         else if (tid == IWL_AGG_ALL_TID)
 328                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
 329                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 330         if (priv->cfg->use_rts_for_ht) {
 331                 /*
 332                  * switch to RTS/CTS if it is the prefer protection method
 333                  * for HT traffic
 334                  */
 335                 IWL_DEBUG_HT(priv, "use RTS/CTS protection for HT\n");
 336                 priv->staging_rxon.flags &= ~RXON_FLG_SELF_CTS_EN;
 337                 iwlcore_commit_rxon(priv);
 338         }
 339 }
 340
 341 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
 342 {
 343         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
 344                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
 345                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
 346 }
 347
 348 /*
 349  * Static function to get the expected throughput from an iwl_scale_tbl_info
 350  * that wraps a NULL pointer check
 351  */
 352 static s32 get_expected_tpt(struct iwl_scale_tbl_info *tbl, int rs_index)
 353 {
 354         if (tbl->expected_tpt)
 355                 return tbl->expected_tpt[rs_index];
 356         return 0;
 357 }
 358
 359 /**
 360  * rs_collect_tx_data - Update the success/failure sliding window
 361  *
 362  * We keep a sliding window of the last 62 packets transmitted
 363  * at this rate.  window->data contains the bitmask of successful
 364  * packets.
 365  */
 366 static int rs_collect_tx_data(struct iwl_scale_tbl_info *tbl,
 367                               int scale_index, int attempts, int successes)
 368 {
 369         struct iwl_rate_scale_data *window = NULL;
 370         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 371         s32 fail_count, tpt;
 372
 373         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 374                 return -EINVAL;
 375
 376         /* Select window for current tx bit rate */
 377         window = &(tbl->win[scale_index]);
 378
 379         /* Get expected throughput */
 380         tpt = get_expected_tpt(tbl, scale_index);
 381
 382         /*
 383          * Keep track of only the latest 62 tx frame attempts in this rate's
 384          * history window; anything older isn't really relevant any more.
 385          * If we have filled up the sliding window, drop the oldest attempt;
 386          * if the oldest attempt (highest bit in bitmap) shows "success",
 387          * subtract "1" from the success counter (this is the main reason
 388          * we keep these bitmaps!).
 389          */
 390         while (attempts > 0) {
 391                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 392
 393                         /* remove earliest */
 394                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 395
 396                         if (window->data & mask) {
 397                                 window->data &= ~mask;
 398                                 window->success_counter--;
 399                         }
 400                 }
 401
 402                 /* Increment frames-attempted counter */
 403                 window->counter++;
 404
 405                 /* Shift bitmap by one frame to throw away oldest history */
 406                 window->data <<= 1;
 407
 408                 /* Mark the most recent #successes attempts as successful */
 409                 if (successes > 0) {
 410                         window->success_counter++;
 411                         window->data |= 0x1;
 412                         successes--;
 413                 }
 414
 415                 attempts--;
 416         }
 417
 418         /* Calculate current success ratio, avoid divide-by-0! */
 419         if (window->counter > 0)
 420                 window->success_ratio = 128 * (100 * window->success_counter)
 421                                         / window->counter;
 422         else
 423                 window->success_ratio = IWL_INVALID_VALUE;
 424
 425         fail_count = window->counter - window->success_counter;
 426
 427         /* Calculate average throughput, if we have enough history. */
 428         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 429             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 430                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 431         else
 432                 window->average_tpt = IWL_INVALID_VALUE;
 433
 434         /* Tag this window as having been updated */
 435         window->stamp = jiffies;
 436
 437         return 0;
 438 }
 439
 440 /*
 441  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 442  */
 443 /* FIXME:RS:remove this function and put the flags statically in the table */
 444 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 445                                  struct iwl_scale_tbl_info *tbl,
 446                                  int index, u8 use_green)
 447 {
 448         u32 rate_n_flags = 0;
 449
 450         if (is_legacy(tbl->lq_type)) {
 451                 rate_n_flags = iwl_rates[index].plcp;
 452                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 453                         rate_n_flags |= RATE_MCS_CCK_MSK;
 454
 455         } else if (is_Ht(tbl->lq_type)) {
 456                 if (index > IWL_LAST_OFDM_RATE) {
 457                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 458                         index = IWL_LAST_OFDM_RATE;
 459                 }
 460                 rate_n_flags = RATE_MCS_HT_MSK;
 461
 462                 if (is_siso(tbl->lq_type))
 463                         rate_n_flags |= iwl_rates[index].plcp_siso;
 464                 else if (is_mimo2(tbl->lq_type))
 465                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 466                 else
 467                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 468         } else {
 469                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 470         }
 471
 472         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 473                                                      RATE_MCS_ANT_ABC_MSK);
 474
 475         if (is_Ht(tbl->lq_type)) {
 476                 if (tbl->is_ht40) {
 477                         if (tbl->is_dup)
 478                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 479                         else
 480                                 rate_n_flags |= RATE_MCS_HT40_MSK;
 481                 }
 482                 if (tbl->is_SGI)
 483                         rate_n_flags |= RATE_MCS_SGI_MSK;
 484
 485                 if (use_green) {
 486                         rate_n_flags |= RATE_MCS_GF_MSK;
 487                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 488                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 489                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 490                         }
 491                 }
 492         }
 493         return rate_n_flags;
 494 }
 495
 496 /*
 497  * Interpret uCode API's rate_n_flags format,
 498  * fill "search" or "active" tx mode table.
 499  */
 500 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 501                                     enum ieee80211_band band,
 502                                     struct iwl_scale_tbl_info *tbl,
 503                                     int *rate_idx)
 504 {
 505         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 506         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 507         u8 mcs;
 508
 509         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 510
 511         if (*rate_idx  == IWL_RATE_INVALID) {
 512                 *rate_idx = -1;
 513                 return -EINVAL;
 514         }
 515         tbl->is_SGI = 0;        /* default legacy setup */
 516         tbl->is_ht40 = 0;
 517         tbl->is_dup = 0;
 518         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 519         tbl->lq_type = LQ_NONE;
 520         tbl->max_search = IWL_MAX_SEARCH;
 521
 522         /* legacy rate format */
 523         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 524                 if (num_of_ant == 1) {
 525                         if (band == IEEE80211_BAND_5GHZ)
 526                                 tbl->lq_type = LQ_A;
 527                         else
 528                                 tbl->lq_type = LQ_G;
 529                 }
 530         /* HT rate format */
 531         } else {
 532                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 533                         tbl->is_SGI = 1;
 534
 535                 if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
 536                     (rate_n_flags & RATE_MCS_DUP_MSK))
 537                         tbl->is_ht40 = 1;
 538
 539                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 540                         tbl->is_dup = 1;
 541
 542                 mcs = rs_extract_rate(rate_n_flags);
 543
 544                 /* SISO */
 545                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 546                         if (num_of_ant == 1)
 547                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 548                 /* MIMO2 */
 549                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 550                         if (num_of_ant == 2)
 551                                 tbl->lq_type = LQ_MIMO2;
 552                 /* MIMO3 */
 553                 } else {
 554                         if (num_of_ant == 3) {
 555                                 tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
 556                                 tbl->lq_type = LQ_MIMO3;
 557                         }
 558                 }
 559         }
 560         return 0;
 561 }
 562
 563 /* switch to another antenna/antennas and return 1 */
 564 /* if no other valid antenna found, return 0 */
 565 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 566                              struct iwl_scale_tbl_info *tbl)
 567 {
 568         u8 new_ant_type;
 569
 570         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 571                 return 0;
 572
 573         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 574                 return 0;
 575
 576         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 577
 578         while ((new_ant_type != tbl->ant_type) &&
 579                !rs_is_valid_ant(valid_ant, new_ant_type))
 580                 new_ant_type = ant_toggle_lookup[new_ant_type];
 581
 582         if (new_ant_type == tbl->ant_type)
 583                 return 0;
 584
 585         tbl->ant_type = new_ant_type;
 586         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 587         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 588         return 1;
 589 }
 590
 591 /**
 592  * Green-field mode is valid if the station supports it and
 593  * there are no non-GF stations present in the BSS.
 594  */
 595 static inline u8 rs_use_green(struct ieee80211_sta *sta,
 596                               struct iwl_ht_config *ht_conf)
 597 {
 598         return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
 599                 !(ht_conf->non_GF_STA_present);
 600 }
 601
 602 /**
 603  * rs_get_supported_rates - get the available rates
 604  *
 605  * if management frame or broadcast frame only return
 606  * basic available rates.
 607  *
 608  */
 609 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 610                                   struct ieee80211_hdr *hdr,
 611                                   enum iwl_table_type rate_type)
 612 {
 613         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 614             lq_sta->active_rate_basic)
 615                 return lq_sta->active_rate_basic;
 616
 617         if (is_legacy(rate_type)) {
 618                 return lq_sta->active_legacy_rate;
 619         } else {
 620                 if (is_siso(rate_type))
 621                         return lq_sta->active_siso_rate;
 622                 else if (is_mimo2(rate_type))
 623                         return lq_sta->active_mimo2_rate;
 624                 else
 625                         return lq_sta->active_mimo3_rate;
 626         }
 627 }
 628
 629 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 630                                 int rate_type)
 631 {
 632         u8 high = IWL_RATE_INVALID;
 633         u8 low = IWL_RATE_INVALID;
 634
 635         /* 802.11A or ht walks to the next literal adjacent rate in
 636          * the rate table */
 637         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 638                 int i;
 639                 u32 mask;
 640
 641                 /* Find the previous rate that is in the rate mask */
 642                 i = index - 1;
 643                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 644                         if (rate_mask & mask) {
 645                                 low = i;
 646                                 break;
 647                         }
 648                 }
 649
 650                 /* Find the next rate that is in the rate mask */
 651                 i = index + 1;
 652                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 653                         if (rate_mask & mask) {
 654                                 high = i;
 655                                 break;
 656                         }
 657                 }
 658
 659                 return (high << 8) | low;
 660         }
 661
 662         low = index;
 663         while (low != IWL_RATE_INVALID) {
 664                 low = iwl_rates[low].prev_rs;
 665                 if (low == IWL_RATE_INVALID)
 666                         break;
 667                 if (rate_mask & (1 << low))
 668                         break;
 669                 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
 670         }
 671
 672         high = index;
 673         while (high != IWL_RATE_INVALID) {
 674                 high = iwl_rates[high].next_rs;
 675                 if (high == IWL_RATE_INVALID)
 676                         break;
 677                 if (rate_mask & (1 << high))
 678                         break;
 679                 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
 680         }
 681
 682         return (high << 8) | low;
 683 }
 684
 685 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 686                              struct iwl_scale_tbl_info *tbl,
 687                              u8 scale_index, u8 ht_possible)
 688 {
 689         s32 low;
 690         u16 rate_mask;
 691         u16 high_low;
 692         u8 switch_to_legacy = 0;
 693         u8 is_green = lq_sta->is_green;
 694         struct iwl_priv *priv = lq_sta->drv;
 695
 696         /* check if we need to switch from HT to legacy rates.
 697          * assumption is that mandatory rates (1Mbps or 6Mbps)
 698          * are always supported (spec demand) */
 699         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 700                 switch_to_legacy = 1;
 701                 scale_index = rs_ht_to_legacy[scale_index];
 702                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 703                         tbl->lq_type = LQ_A;
 704                 else
 705                         tbl->lq_type = LQ_G;
 706
 707                 if (num_of_ant(tbl->ant_type) > 1)
 708                         tbl->ant_type =
 709                                 first_antenna(priv->hw_params.valid_tx_ant);
 710
 711                 tbl->is_ht40 = 0;
 712                 tbl->is_SGI = 0;
 713                 tbl->max_search = IWL_MAX_SEARCH;
 714         }
 715
 716         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 717
 718         /* Mask with station rate restriction */
 719         if (is_legacy(tbl->lq_type)) {
 720                 /* supp_rates has no CCK bits in A mode */
 721                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 722                         rate_mask  = (u16)(rate_mask &
 723                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 724                 else
 725                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 726         }
 727
 728         /* If we switched from HT to legacy, check current rate */
 729         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 730                 low = scale_index;
 731                 goto out;
 732         }
 733
 734         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 735                                         tbl->lq_type);
 736         low = high_low & 0xff;
 737
 738         if (low == IWL_RATE_INVALID)
 739                 low = scale_index;
 740
 741 out:
 742         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 743 }
 744
 745 /*
 746  * Simple function to compare two rate scale table types
 747  */
 748 static bool table_type_matches(struct iwl_scale_tbl_info *a,
 749                                struct iwl_scale_tbl_info *b)
 750 {
 751         return (a->lq_type == b->lq_type) && (a->ant_type == b->ant_type) &&
 752                 (a->is_SGI == b->is_SGI);
 753 }
 754
 755 /*
 756  * mac80211 sends us Tx status
 757  */
 758 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 759                          struct ieee80211_sta *sta, void *priv_sta,
 760                          struct sk_buff *skb)
 761 {
 762         int legacy_success;
 763         int retries;
 764         int rs_index, mac_index, i;
 765         struct iwl_lq_sta *lq_sta = priv_sta;
 766         struct iwl_link_quality_cmd *table;
 767         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 768         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 769         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 770         enum mac80211_rate_control_flags mac_flags;
 771         u32 tx_rate;
 772         struct iwl_scale_tbl_info tbl_type;
 773         struct iwl_scale_tbl_info *curr_tbl, *other_tbl, *tmp_tbl;
 774
 775         IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 776
 777         if (!ieee80211_is_data(hdr->frame_control) ||
 778             info->flags & IEEE80211_TX_CTL_NO_ACK)
 779                 return;
 780
 781         /* This packet was aggregated but doesn't carry status info */
 782         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 783             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 784                 return;
 785
 786         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 787             !lq_sta->ibss_sta_added)
 788                 return;
 789
 790         /*
 791          * Ignore this Tx frame response if its initial rate doesn't match
 792          * that of latest Link Quality command.  There may be stragglers
 793          * from a previous Link Quality command, but we're no longer interested
 794          * in those; they're either from the "active" mode while we're trying
 795          * to check "search" mode, or a prior "search" mode after we've moved
 796          * to a new "search" mode (which might become the new "active" mode).
 797          */
 798         table = &lq_sta->lq;
 799         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 800         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 801         if (priv->band == IEEE80211_BAND_5GHZ)
 802                 rs_index -= IWL_FIRST_OFDM_RATE;
 803         mac_flags = info->status.rates[0].flags;
 804         mac_index = info->status.rates[0].idx;
 805         /* For HT packets, map MCS to PLCP */
 806         if (mac_flags & IEEE80211_TX_RC_MCS) {
 807                 mac_index &= RATE_MCS_CODE_MSK; /* Remove # of streams */
 808                 if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE))
 809                         mac_index++;
 810                 /*
 811                  * mac80211 HT index is always zero-indexed; we need to move
 812                  * HT OFDM rates after CCK rates in 2.4 GHz band
 813                  */
 814                 if (priv->band == IEEE80211_BAND_2GHZ)
 815                         mac_index += IWL_FIRST_OFDM_RATE;
 816         }
 817         /* Here we actually compare this rate to the latest LQ command */
 818         if ((mac_index < 0) ||
 819             (tbl_type.is_SGI != !!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) ||
 820             (tbl_type.is_ht40 != !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 821             (tbl_type.is_dup != !!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) ||
 822             (tbl_type.ant_type != info->antenna_sel_tx) ||
 823             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(mac_flags & IEEE80211_TX_RC_MCS)) ||
 824             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 825             (rs_index != mac_index)) {
 826                 IWL_DEBUG_RATE(priv, "initial rate %d does not match %d (0x%x)\n", mac_index, rs_index, tx_rate);
 827                 /*
 828                  * Since rates mis-match, the last LQ command may have failed.
 829                  * After IWL_MISSED_RATE_MAX mis-matches, resync the uCode with
 830                  * ... driver.
 831                  */
 832                 lq_sta->missed_rate_counter++;
 833                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 834                         lq_sta->missed_rate_counter = 0;
 835                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 836                 }
 837                 /* Regardless, ignore this status info for outdated rate */
 838                 return;
 839         } else
 840                 /* Rate did match, so reset the missed_rate_counter */
 841                 lq_sta->missed_rate_counter = 0;
 842
 843         /* Figure out if rate scale algorithm is in active or search table */
 844         if (table_type_matches(&tbl_type,
 845                                 &(lq_sta->lq_info[lq_sta->active_tbl]))) {
 846                 curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 847                 other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 848         } else if (table_type_matches(&tbl_type,
 849                                 &lq_sta->lq_info[1 - lq_sta->active_tbl])) {
 850                 curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 851                 other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 852         } else {
 853                 IWL_DEBUG_RATE(priv, "Neither active nor search matches tx rate\n");
 854                 return;
 855         }
 856
 857         /*
 858          * Updating the frame history depends on whether packets were
 859          * aggregated.
 860          *
 861          * For aggregation, all packets were transmitted at the same rate, the
 862          * first index into rate scale table.
 863          */
 864         if (info->flags & IEEE80211_TX_STAT_AMPDU) {
 865                 tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 866                 rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type,
 867                                 &rs_index);
 868                 rs_collect_tx_data(curr_tbl, rs_index,
 869                                    info->status.ampdu_ack_len,
 870                                    info->status.ampdu_ack_map);
 871
 872                 /* Update success/fail counts if not searching for new mode */
 873                 if (lq_sta->stay_in_tbl) {
 874                         lq_sta->total_success += info->status.ampdu_ack_map;
 875                         lq_sta->total_failed += (info->status.ampdu_ack_len -
 876                                         info->status.ampdu_ack_map);
 877                 }
 878         } else {
 879         /*
 880          * For legacy, update frame history with for each Tx retry.
 881          */
 882                 retries = info->status.rates[0].count - 1;
 883                 /* HW doesn't send more than 15 retries */
 884                 retries = min(retries, 15);
 885
 886                 /* The last transmission may have been successful */
 887                 legacy_success = !!(info->flags & IEEE80211_TX_STAT_ACK);
 888                 /* Collect data for each rate used during failed TX attempts */
 889                 for (i = 0; i <= retries; ++i) {
 890                         tx_rate = le32_to_cpu(table->rs_table[i].rate_n_flags);
 891                         rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 892                                         &tbl_type, &rs_index);
 893                         /*
 894                          * Only collect stats if retried rate is in the same RS
 895                          * table as active/search.
 896                          */
 897                         if (table_type_matches(&tbl_type, curr_tbl))
 898                                 tmp_tbl = curr_tbl;
 899                         else if (table_type_matches(&tbl_type, other_tbl))
 900                                 tmp_tbl = other_tbl;
 901                         else
 902                                 continue;
 903                         rs_collect_tx_data(tmp_tbl, rs_index, 1,
 904                                            i < retries ? 0 : legacy_success);
 905                 }
 906
 907                 /* Update success/fail counts if not searching for new mode */
 908                 if (lq_sta->stay_in_tbl) {
 909                         lq_sta->total_success += legacy_success;
 910                         lq_sta->total_failed += retries + (1 - legacy_success);
 911                 }
 912         }
 913         /* The last TX rate is cached in lq_sta; it's set in if/else above */
 914         lq_sta->last_rate_n_flags = tx_rate;
 915
 916         /* See if there's a better rate or modulation mode to try. */
 917         if (sta && sta->supp_rates[sband->band])
 918                 rs_rate_scale_perform(priv, skb, sta, lq_sta);
 919 }
 920
 921 /*
 922  * Begin a period of staying with a selected modulation mode.
 923  * Set "stay_in_tbl" flag to prevent any mode switches.
 924  * Set frame tx success limits according to legacy vs. high-throughput,
 925  * and reset overall (spanning all rates) tx success history statistics.
 926  * These control how long we stay using same modulation mode before
 927  * searching for a new mode.
 928  */
 929 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
 930                                  struct iwl_lq_sta *lq_sta)
 931 {
 932         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
 933         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
 934         if (is_legacy) {
 935                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
 936                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
 937                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
 938         } else {
 939                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
 940                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
 941                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
 942         }
 943         lq_sta->table_count = 0;
 944         lq_sta->total_failed = 0;
 945         lq_sta->total_success = 0;
 946         lq_sta->flush_timer = jiffies;
 947         lq_sta->action_counter = 0;
 948 }
 949
 950 /*
 951  * Find correct throughput table for given mode of modulation
 952  */
 953 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
 954                                       struct iwl_scale_tbl_info *tbl)
 955 {
 956         /* Used to choose among HT tables */
 957         s32 (*ht_tbl_pointer)[IWL_RATE_COUNT];
 958
 959         /* Check for invalid LQ type */
 960         if (WARN_ON_ONCE(!is_legacy(tbl->lq_type) && !is_Ht(tbl->lq_type))) {
 961                 tbl->expected_tpt = expected_tpt_legacy;
 962                 return;
 963         }
 964
 965         /* Legacy rates have only one table */
 966         if (is_legacy(tbl->lq_type)) {
 967                 tbl->expected_tpt = expected_tpt_legacy;
 968                 return;
 969         }
 970
 971         /* Choose among many HT tables depending on number of streams
 972          * (SISO/MIMO2/MIMO3), channel width (20/40), SGI, and aggregation
 973          * status */
 974         if (is_siso(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 975                 ht_tbl_pointer = expected_tpt_siso20MHz;
 976         else if (is_siso(tbl->lq_type))
 977                 ht_tbl_pointer = expected_tpt_siso40MHz;
 978         else if (is_mimo2(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 979                 ht_tbl_pointer = expected_tpt_mimo2_20MHz;
 980         else if (is_mimo2(tbl->lq_type))
 981                 ht_tbl_pointer = expected_tpt_mimo2_40MHz;
 982         else if (is_mimo3(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 983                 ht_tbl_pointer = expected_tpt_mimo3_20MHz;
 984         else /* if (is_mimo3(tbl->lq_type)) <-- must be true */
 985                 ht_tbl_pointer = expected_tpt_mimo3_40MHz;
 986
 987         if (!tbl->is_SGI && !lq_sta->is_agg)            /* Normal */
 988                 tbl->expected_tpt = ht_tbl_pointer[0];
 989         else if (tbl->is_SGI && !lq_sta->is_agg)        /* SGI */
 990                 tbl->expected_tpt = ht_tbl_pointer[1];
 991         else if (!tbl->is_SGI && lq_sta->is_agg)        /* AGG */
 992                 tbl->expected_tpt = ht_tbl_pointer[2];
 993         else                                            /* AGG+SGI */
 994                 tbl->expected_tpt = ht_tbl_pointer[3];
 995 }
 996
 997 /*
 998  * Find starting rate for new "search" high-throughput mode of modulation.
 999  * Goal is to find lowest expected rate (under perfect conditions) that is
1000  * above the current measured throughput of "active" mode, to give new mode
1001  * a fair chance to prove itself without too many challenges.
1002  *
1003  * This gets called when transitioning to more aggressive modulation
1004  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1005  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1006  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1007  * bit rate will typically need to increase, but not if performance was bad.
1008  */
1009 static s32 rs_get_best_rate(struct iwl_priv *priv,
1010                             struct iwl_lq_sta *lq_sta,
1011                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1012                             u16 rate_mask, s8 index)
1013 {
1014         /* "active" values */
1015         struct iwl_scale_tbl_info *active_tbl =
1016             &(lq_sta->lq_info[lq_sta->active_tbl]);
1017         s32 active_sr = active_tbl->win[index].success_ratio;
1018         s32 active_tpt = active_tbl->expected_tpt[index];
1019
1020         /* expected "search" throughput */
1021         s32 *tpt_tbl = tbl->expected_tpt;
1022
1023         s32 new_rate, high, low, start_hi;
1024         u16 high_low;
1025         s8 rate = index;
1026
1027         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1028
1029         for (; ;) {
1030                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1031                                                 tbl->lq_type);
1032
1033                 low = high_low & 0xff;
1034                 high = (high_low >> 8) & 0xff;
1035
1036                 /*
1037                  * Lower the "search" bit rate, to give new "search" mode
1038                  * approximately the same throughput as "active" if:
1039                  *
1040                  * 1) "Active" mode has been working modestly well (but not
1041                  *    great), and expected "search" throughput (under perfect
1042                  *    conditions) at candidate rate is above the actual
1043                  *    measured "active" throughput (but less than expected
1044                  *    "active" throughput under perfect conditions).
1045                  * OR
1046                  * 2) "Active" mode has been working perfectly or very well
1047                  *    and expected "search" throughput (under perfect
1048                  *    conditions) at candidate rate is above expected
1049                  *    "active" throughput (under perfect conditions).
1050                  */
1051                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1052                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1053                       (active_sr <= IWL_RATE_HIGH_TH) &&
1054                       (tpt_tbl[rate] <= active_tpt))) ||
1055                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1056                      (tpt_tbl[rate] > active_tpt))) {
1057
1058                         /* (2nd or later pass)
1059                          * If we've already tried to raise the rate, and are
1060                          * now trying to lower it, use the higher rate. */
1061                         if (start_hi != IWL_RATE_INVALID) {
1062                                 new_rate = start_hi;
1063                                 break;
1064                         }
1065
1066                         new_rate = rate;
1067
1068                         /* Loop again with lower rate */
1069                         if (low != IWL_RATE_INVALID)
1070                                 rate = low;
1071
1072                         /* Lower rate not available, use the original */
1073                         else
1074                                 break;
1075
1076                 /* Else try to raise the "search" rate to match "active" */
1077                 } else {
1078                         /* (2nd or later pass)
1079                          * If we've already tried to lower the rate, and are
1080                          * now trying to raise it, use the lower rate. */
1081                         if (new_rate != IWL_RATE_INVALID)
1082                                 break;
1083
1084                         /* Loop again with higher rate */
1085                         else if (high != IWL_RATE_INVALID) {
1086                                 start_hi = high;
1087                                 rate = high;
1088
1089                         /* Higher rate not available, use the original */
1090                         } else {
1091                                 new_rate = rate;
1092                                 break;
1093                         }
1094                 }
1095         }
1096
1097         return new_rate;
1098 }
1099
1100 /*
1101  * Set up search table for MIMO2
1102  */
1103 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1104                              struct iwl_lq_sta *lq_sta,
1105                              struct ieee80211_conf *conf,
1106                              struct ieee80211_sta *sta,
1107                              struct iwl_scale_tbl_info *tbl, int index)
1108 {
1109         u16 rate_mask;
1110         s32 rate;
1111         s8 is_green = lq_sta->is_green;
1112
1113         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1114                 return -1;
1115
1116         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1117                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1118                 return -1;
1119
1120         /* Need both Tx chains/antennas to support MIMO */
1121         if (priv->hw_params.tx_chains_num < 2)
1122                 return -1;
1123
1124         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1125
1126         tbl->lq_type = LQ_MIMO2;
1127         tbl->is_dup = lq_sta->is_dup;
1128         tbl->action = 0;
1129         tbl->max_search = IWL_MAX_SEARCH;
1130         rate_mask = lq_sta->active_mimo2_rate;
1131
1132         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1133                 tbl->is_ht40 = 1;
1134         else
1135                 tbl->is_ht40 = 0;
1136
1137         rs_set_expected_tpt_table(lq_sta, tbl);
1138
1139         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1140
1141         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1142         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1143                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1144                                                 rate, rate_mask);
1145                 return -1;
1146         }
1147         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1148
1149         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1150                      tbl->current_rate, is_green);
1151         return 0;
1152 }
1153
1154 /*
1155  * Set up search table for MIMO3
1156  */
1157 static int rs_switch_to_mimo3(struct iwl_priv *priv,
1158                              struct iwl_lq_sta *lq_sta,
1159                              struct ieee80211_conf *conf,
1160                              struct ieee80211_sta *sta,
1161                              struct iwl_scale_tbl_info *tbl, int index)
1162 {
1163         u16 rate_mask;
1164         s32 rate;
1165         s8 is_green = lq_sta->is_green;
1166
1167         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1168                 return -1;
1169
1170         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1171                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1172                 return -1;
1173
1174         /* Need both Tx chains/antennas to support MIMO */
1175         if (priv->hw_params.tx_chains_num < 3)
1176                 return -1;
1177
1178         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO3\n");
1179
1180         tbl->lq_type = LQ_MIMO3;
1181         tbl->is_dup = lq_sta->is_dup;
1182         tbl->action = 0;
1183         tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
1184         rate_mask = lq_sta->active_mimo3_rate;
1185
1186         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1187                 tbl->is_ht40 = 1;
1188         else
1189                 tbl->is_ht40 = 0;
1190
1191         rs_set_expected_tpt_table(lq_sta, tbl);
1192
1193         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1194
1195         IWL_DEBUG_RATE(priv, "LQ: MIMO3 best rate %d mask %X\n",
1196                 rate, rate_mask);
1197         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1198                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1199                                                 rate, rate_mask);
1200                 return -1;
1201         }
1202         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1203
1204         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1205                      tbl->current_rate, is_green);
1206         return 0;
1207 }
1208
1209 /*
1210  * Set up search table for SISO
1211  */
1212 static int rs_switch_to_siso(struct iwl_priv *priv,
1213                              struct iwl_lq_sta *lq_sta,
1214                              struct ieee80211_conf *conf,
1215                              struct ieee80211_sta *sta,
1216                              struct iwl_scale_tbl_info *tbl, int index)
1217 {
1218         u16 rate_mask;
1219         u8 is_green = lq_sta->is_green;
1220         s32 rate;
1221
1222         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1223                 return -1;
1224
1225         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1226
1227         tbl->is_dup = lq_sta->is_dup;
1228         tbl->lq_type = LQ_SISO;
1229         tbl->action = 0;
1230         tbl->max_search = IWL_MAX_SEARCH;
1231         rate_mask = lq_sta->active_siso_rate;
1232
1233         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1234                 tbl->is_ht40 = 1;
1235         else
1236                 tbl->is_ht40 = 0;
1237
1238         if (is_green)
1239                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1240
1241         rs_set_expected_tpt_table(lq_sta, tbl);
1242         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1243
1244         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1245         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1246                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1247                              rate, rate_mask);
1248                 return -1;
1249         }
1250         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1251         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1252                      tbl->current_rate, is_green);
1253         return 0;
1254 }
1255
1256 /*
1257  * Try to switch to new modulation mode from legacy
1258  */
1259 static int rs_move_legacy_other(struct iwl_priv *priv,
1260                                 struct iwl_lq_sta *lq_sta,
1261                                 struct ieee80211_conf *conf,
1262                                 struct ieee80211_sta *sta,
1263                                 int index)
1264 {
1265         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1266         struct iwl_scale_tbl_info *search_tbl =
1267                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1268         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1269         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1270                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1271         u8 start_action = tbl->action;
1272         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1273         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1274         int ret = 0;
1275         u8 update_search_tbl_counter = 0;
1276
1277         if (!iwl_ht_enabled(priv))
1278                 /* stay in Legacy */
1279                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1280         else if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1281                    tbl->action > IWL_LEGACY_SWITCH_SISO)
1282                 tbl->action = IWL_LEGACY_SWITCH_SISO;
1283         for (; ;) {
1284                 lq_sta->action_counter++;
1285                 switch (tbl->action) {
1286                 case IWL_LEGACY_SWITCH_ANTENNA1:
1287                 case IWL_LEGACY_SWITCH_ANTENNA2:
1288                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1289
1290                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1291                                                         tx_chains_num <= 1) ||
1292                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1293                                                         tx_chains_num <= 2))
1294                                 break;
1295
1296                         /* Don't change antenna if success has been great */
1297                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1298                                 break;
1299
1300                         /* Set up search table to try other antenna */
1301                         memcpy(search_tbl, tbl, sz);
1302
1303                         if (rs_toggle_antenna(valid_tx_ant,
1304                                 &search_tbl->current_rate, search_tbl)) {
1305                                 update_search_tbl_counter = 1;
1306                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1307                                 goto out;
1308                         }
1309                         break;
1310                 case IWL_LEGACY_SWITCH_SISO:
1311                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1312
1313                         /* Set up search table to try SISO */
1314                         memcpy(search_tbl, tbl, sz);
1315                         search_tbl->is_SGI = 0;
1316                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1317                                                  search_tbl, index);
1318                         if (!ret) {
1319                                 lq_sta->action_counter = 0;
1320                                 goto out;
1321                         }
1322
1323                         break;
1324                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1325                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1326                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1327                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1328
1329                         /* Set up search table to try MIMO */
1330                         memcpy(search_tbl, tbl, sz);
1331                         search_tbl->is_SGI = 0;
1332
1333                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1334                                 search_tbl->ant_type = ANT_AB;
1335                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1336                                 search_tbl->ant_type = ANT_AC;
1337                         else
1338                                 search_tbl->ant_type = ANT_BC;
1339
1340                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1341                                 break;
1342
1343                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1344                                                  search_tbl, index);
1345                         if (!ret) {
1346                                 lq_sta->action_counter = 0;
1347                                 goto out;
1348                         }
1349                         break;
1350
1351                 case IWL_LEGACY_SWITCH_MIMO3_ABC:
1352                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO3\n");
1353
1354                         /* Set up search table to try MIMO3 */
1355                         memcpy(search_tbl, tbl, sz);
1356                         search_tbl->is_SGI = 0;
1357
1358                         search_tbl->ant_type = ANT_ABC;
1359
1360                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1361                                 break;
1362
1363                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1364                                                  search_tbl, index);
1365                         if (!ret) {
1366                                 lq_sta->action_counter = 0;
1367                                 goto out;
1368                         }
1369                         break;
1370                 }
1371                 tbl->action++;
1372                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1373                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1374
1375                 if (tbl->action == start_action)
1376                         break;
1377
1378         }
1379         search_tbl->lq_type = LQ_NONE;
1380         return 0;
1381
1382 out:
1383         lq_sta->search_better_tbl = 1;
1384         tbl->action++;
1385         if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1386                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1387         if (update_search_tbl_counter)
1388                 search_tbl->action = tbl->action;
1389         return 0;
1390
1391 }
1392
1393 /*
1394  * Try to switch to new modulation mode from SISO
1395  */
1396 static int rs_move_siso_to_other(struct iwl_priv *priv,
1397                                  struct iwl_lq_sta *lq_sta,
1398                                  struct ieee80211_conf *conf,
1399                                  struct ieee80211_sta *sta, int index)
1400 {
1401         u8 is_green = lq_sta->is_green;
1402         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1403         struct iwl_scale_tbl_info *search_tbl =
1404                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1405         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1406         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1407         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1408                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1409         u8 start_action = tbl->action;
1410         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1411         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1412         u8 update_search_tbl_counter = 0;
1413         int ret;
1414
1415         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1416             tbl->action > IWL_SISO_SWITCH_ANTENNA2) {
1417                 /* stay in SISO */
1418                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1419         }
1420         for (;;) {
1421                 lq_sta->action_counter++;
1422                 switch (tbl->action) {
1423                 case IWL_SISO_SWITCH_ANTENNA1:
1424                 case IWL_SISO_SWITCH_ANTENNA2:
1425                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1426
1427                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1428                                                         tx_chains_num <= 1) ||
1429                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1430                                                         tx_chains_num <= 2))
1431                                 break;
1432
1433                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1434                                 break;
1435
1436                         memcpy(search_tbl, tbl, sz);
1437                         if (rs_toggle_antenna(valid_tx_ant,
1438                                        &search_tbl->current_rate, search_tbl)) {
1439                                 update_search_tbl_counter = 1;
1440                                 goto out;
1441                         }
1442                         break;
1443                 case IWL_SISO_SWITCH_MIMO2_AB:
1444                 case IWL_SISO_SWITCH_MIMO2_AC:
1445                 case IWL_SISO_SWITCH_MIMO2_BC:
1446                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1447                         memcpy(search_tbl, tbl, sz);
1448                         search_tbl->is_SGI = 0;
1449
1450                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1451                                 search_tbl->ant_type = ANT_AB;
1452                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1453                                 search_tbl->ant_type = ANT_AC;
1454                         else
1455                                 search_tbl->ant_type = ANT_BC;
1456
1457                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1458                                 break;
1459
1460                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1461                                                  search_tbl, index);
1462                         if (!ret)
1463                                 goto out;
1464                         break;
1465                 case IWL_SISO_SWITCH_GI:
1466                         if (!tbl->is_ht40 && !(ht_cap->cap &
1467                                                 IEEE80211_HT_CAP_SGI_20))
1468                                 break;
1469                         if (tbl->is_ht40 && !(ht_cap->cap &
1470                                                 IEEE80211_HT_CAP_SGI_40))
1471                                 break;
1472
1473                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1474
1475                         memcpy(search_tbl, tbl, sz);
1476                         if (is_green) {
1477                                 if (!tbl->is_SGI)
1478                                         break;
1479                                 else
1480                                         IWL_ERR(priv,
1481                                                 "SGI was set in GF+SISO\n");
1482                         }
1483                         search_tbl->is_SGI = !tbl->is_SGI;
1484                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1485                         if (tbl->is_SGI) {
1486                                 s32 tpt = lq_sta->last_tpt / 100;
1487                                 if (tpt >= search_tbl->expected_tpt[index])
1488                                         break;
1489                         }
1490                         search_tbl->current_rate =
1491                                 rate_n_flags_from_tbl(priv, search_tbl,
1492                                                       index, is_green);
1493                         update_search_tbl_counter = 1;
1494                         goto out;
1495                 case IWL_SISO_SWITCH_MIMO3_ABC:
1496                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO3\n");
1497                         memcpy(search_tbl, tbl, sz);
1498                         search_tbl->is_SGI = 0;
1499                         search_tbl->ant_type = ANT_ABC;
1500
1501                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1502                                 break;
1503
1504                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1505                                                  search_tbl, index);
1506                         if (!ret)
1507                                 goto out;
1508                         break;
1509                 }
1510                 tbl->action++;
1511                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1512                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1513
1514                 if (tbl->action == start_action)
1515                         break;
1516         }
1517         search_tbl->lq_type = LQ_NONE;
1518         return 0;
1519
1520  out:
1521         lq_sta->search_better_tbl = 1;
1522         tbl->action++;
1523         if (tbl->action > IWL_SISO_SWITCH_MIMO3_ABC)
1524                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1525         if (update_search_tbl_counter)
1526                 search_tbl->action = tbl->action;
1527
1528         return 0;
1529 }
1530
1531 /*
1532  * Try to switch to new modulation mode from MIMO2
1533  */
1534 static int rs_move_mimo2_to_other(struct iwl_priv *priv,
1535                                  struct iwl_lq_sta *lq_sta,
1536                                  struct ieee80211_conf *conf,
1537                                  struct ieee80211_sta *sta, int index)
1538 {
1539         s8 is_green = lq_sta->is_green;
1540         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1541         struct iwl_scale_tbl_info *search_tbl =
1542                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1543         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1544         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1545         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1546                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1547         u8 start_action = tbl->action;
1548         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1549         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1550         u8 update_search_tbl_counter = 0;
1551         int ret;
1552
1553         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1554             (tbl->action < IWL_MIMO2_SWITCH_SISO_A ||
1555              tbl->action > IWL_MIMO2_SWITCH_SISO_C)) {
1556                 /* switch in SISO */
1557                 tbl->action = IWL_MIMO2_SWITCH_SISO_A;
1558         }
1559         for (;;) {
1560                 lq_sta->action_counter++;
1561                 switch (tbl->action) {
1562                 case IWL_MIMO2_SWITCH_ANTENNA1:
1563                 case IWL_MIMO2_SWITCH_ANTENNA2:
1564                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1565
1566                         if (tx_chains_num <= 2)
1567                                 break;
1568
1569                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1570                                 break;
1571
1572                         memcpy(search_tbl, tbl, sz);
1573                         if (rs_toggle_antenna(valid_tx_ant,
1574                                        &search_tbl->current_rate, search_tbl)) {
1575                                 update_search_tbl_counter = 1;
1576                                 goto out;
1577                         }
1578                         break;
1579                 case IWL_MIMO2_SWITCH_SISO_A:
1580                 case IWL_MIMO2_SWITCH_SISO_B:
1581                 case IWL_MIMO2_SWITCH_SISO_C:
1582                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1583
1584                         /* Set up new search table for SISO */
1585                         memcpy(search_tbl, tbl, sz);
1586
1587                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1588                                 search_tbl->ant_type = ANT_A;
1589                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1590                                 search_tbl->ant_type = ANT_B;
1591                         else
1592                                 search_tbl->ant_type = ANT_C;
1593
1594                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1595                                 break;
1596
1597                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1598                                                  search_tbl, index);
1599                         if (!ret)
1600                                 goto out;
1601
1602                         break;
1603
1604                 case IWL_MIMO2_SWITCH_GI:
1605                         if (!tbl->is_ht40 && !(ht_cap->cap &
1606                                                 IEEE80211_HT_CAP_SGI_20))
1607                                 break;
1608                         if (tbl->is_ht40 && !(ht_cap->cap &
1609                                                 IEEE80211_HT_CAP_SGI_40))
1610                                 break;
1611
1612                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1613
1614                         /* Set up new search table for MIMO2 */
1615                         memcpy(search_tbl, tbl, sz);
1616                         search_tbl->is_SGI = !tbl->is_SGI;
1617                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1618                         /*
1619                          * If active table already uses the fastest possible
1620                          * modulation (dual stream with short guard interval),
1621                          * and it's working well, there's no need to look
1622                          * for a better type of modulation!
1623                          */
1624                         if (tbl->is_SGI) {
1625                                 s32 tpt = lq_sta->last_tpt / 100;
1626                                 if (tpt >= search_tbl->expected_tpt[index])
1627                                         break;
1628                         }
1629                         search_tbl->current_rate =
1630                                 rate_n_flags_from_tbl(priv, search_tbl,
1631                                                       index, is_green);
1632                         update_search_tbl_counter = 1;
1633                         goto out;
1634
1635                 case IWL_MIMO2_SWITCH_MIMO3_ABC:
1636                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to MIMO3\n");
1637                         memcpy(search_tbl, tbl, sz);
1638                         search_tbl->is_SGI = 0;
1639                         search_tbl->ant_type = ANT_ABC;
1640
1641                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1642                                 break;
1643
1644                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1645                                                  search_tbl, index);
1646                         if (!ret)
1647                                 goto out;
1648
1649                         break;
1650                 }
1651                 tbl->action++;
1652                 if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1653                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1654
1655                 if (tbl->action == start_action)
1656                         break;
1657         }
1658         search_tbl->lq_type = LQ_NONE;
1659         return 0;
1660  out:
1661         lq_sta->search_better_tbl = 1;
1662         tbl->action++;
1663         if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1664                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1665         if (update_search_tbl_counter)
1666                 search_tbl->action = tbl->action;
1667
1668         return 0;
1669
1670 }
1671
1672 /*
1673  * Try to switch to new modulation mode from MIMO3
1674  */
1675 static int rs_move_mimo3_to_other(struct iwl_priv *priv,
1676                                  struct iwl_lq_sta *lq_sta,
1677                                  struct ieee80211_conf *conf,
1678                                  struct ieee80211_sta *sta, int index)
1679 {
1680         s8 is_green = lq_sta->is_green;
1681         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1682         struct iwl_scale_tbl_info *search_tbl =
1683                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1684         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1685         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1686         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1687                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1688         u8 start_action = tbl->action;
1689         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1690         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1691         int ret;
1692         u8 update_search_tbl_counter = 0;
1693
1694         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1695             (tbl->action < IWL_MIMO3_SWITCH_SISO_A ||
1696              tbl->action > IWL_MIMO3_SWITCH_SISO_C)) {
1697                 /* switch in SISO */
1698                 tbl->action = IWL_MIMO3_SWITCH_SISO_A;
1699         }
1700         for (;;) {
1701                 lq_sta->action_counter++;
1702                 switch (tbl->action) {
1703                 case IWL_MIMO3_SWITCH_ANTENNA1:
1704                 case IWL_MIMO3_SWITCH_ANTENNA2:
1705                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle Antennas\n");
1706
1707                         if (tx_chains_num <= 3)
1708                                 break;
1709
1710                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1711                                 break;
1712
1713                         memcpy(search_tbl, tbl, sz);
1714                         if (rs_toggle_antenna(valid_tx_ant,
1715                                        &search_tbl->current_rate, search_tbl))
1716                                 goto out;
1717                         break;
1718                 case IWL_MIMO3_SWITCH_SISO_A:
1719                 case IWL_MIMO3_SWITCH_SISO_B:
1720                 case IWL_MIMO3_SWITCH_SISO_C:
1721                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to SISO\n");
1722
1723                         /* Set up new search table for SISO */
1724                         memcpy(search_tbl, tbl, sz);
1725
1726                         if (tbl->action == IWL_MIMO3_SWITCH_SISO_A)
1727                                 search_tbl->ant_type = ANT_A;
1728                         else if (tbl->action == IWL_MIMO3_SWITCH_SISO_B)
1729                                 search_tbl->ant_type = ANT_B;
1730                         else
1731                                 search_tbl->ant_type = ANT_C;
1732
1733                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1734                                 break;
1735
1736                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1737                                                  search_tbl, index);
1738                         if (!ret)
1739                                 goto out;
1740
1741                         break;
1742
1743                 case IWL_MIMO3_SWITCH_MIMO2_AB:
1744                 case IWL_MIMO3_SWITCH_MIMO2_AC:
1745                 case IWL_MIMO3_SWITCH_MIMO2_BC:
1746                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to MIMO2\n");
1747
1748                         memcpy(search_tbl, tbl, sz);
1749                         search_tbl->is_SGI = 0;
1750                         if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AB)
1751                                 search_tbl->ant_type = ANT_AB;
1752                         else if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AC)
1753                                 search_tbl->ant_type = ANT_AC;
1754                         else
1755                                 search_tbl->ant_type = ANT_BC;
1756
1757                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1758                                 break;
1759
1760                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1761                                                  search_tbl, index);
1762                         if (!ret)
1763                                 goto out;
1764
1765                         break;
1766
1767                 case IWL_MIMO3_SWITCH_GI:
1768                         if (!tbl->is_ht40 && !(ht_cap->cap &
1769                                                 IEEE80211_HT_CAP_SGI_20))
1770                                 break;
1771                         if (tbl->is_ht40 && !(ht_cap->cap &
1772                                                 IEEE80211_HT_CAP_SGI_40))
1773                                 break;
1774
1775                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle SGI/NGI\n");
1776
1777                         /* Set up new search table for MIMO */
1778                         memcpy(search_tbl, tbl, sz);
1779                         search_tbl->is_SGI = !tbl->is_SGI;
1780                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1781                         /*
1782                          * If active table already uses the fastest possible
1783                          * modulation (dual stream with short guard interval),
1784                          * and it's working well, there's no need to look
1785                          * for a better type of modulation!
1786                          */
1787                         if (tbl->is_SGI) {
1788                                 s32 tpt = lq_sta->last_tpt / 100;
1789                                 if (tpt >= search_tbl->expected_tpt[index])
1790                                         break;
1791                         }
1792                         search_tbl->current_rate =
1793                                 rate_n_flags_from_tbl(priv, search_tbl,
1794                                                       index, is_green);
1795                         update_search_tbl_counter = 1;
1796                         goto out;
1797                 }
1798                 tbl->action++;
1799                 if (tbl->action > IWL_MIMO3_SWITCH_GI)
1800                         tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1801
1802                 if (tbl->action == start_action)
1803                         break;
1804         }
1805         search_tbl->lq_type = LQ_NONE;
1806         return 0;
1807  out:
1808         lq_sta->search_better_tbl = 1;
1809         tbl->action++;
1810         if (tbl->action > IWL_MIMO3_SWITCH_GI)
1811                 tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1812         if (update_search_tbl_counter)
1813                 search_tbl->action = tbl->action;
1814
1815         return 0;
1816
1817 }
1818
1819 /*
1820  * Check whether we should continue using same modulation mode, or
1821  * begin search for a new mode, based on:
1822  * 1) # tx successes or failures while using this mode
1823  * 2) # times calling this function
1824  * 3) elapsed time in this mode (not used, for now)
1825  */
1826 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1827 {
1828         struct iwl_scale_tbl_info *tbl;
1829         int i;
1830         int active_tbl;
1831         int flush_interval_passed = 0;
1832         struct iwl_priv *priv;
1833
1834         priv = lq_sta->drv;
1835         active_tbl = lq_sta->active_tbl;
1836
1837         tbl = &(lq_sta->lq_info[active_tbl]);
1838
1839         /* If we've been disallowing search, see if we should now allow it */
1840         if (lq_sta->stay_in_tbl) {
1841
1842                 /* Elapsed time using current modulation mode */
1843                 if (lq_sta->flush_timer)
1844                         flush_interval_passed =
1845                         time_after(jiffies,
1846                                         (unsigned long)(lq_sta->flush_timer +
1847                                         IWL_RATE_SCALE_FLUSH_INTVL));
1848
1849                 /*
1850                  * Check if we should allow search for new modulation mode.
1851                  * If many frames have failed or succeeded, or we've used
1852                  * this same modulation for a long time, allow search, and
1853                  * reset history stats that keep track of whether we should
1854                  * allow a new search.  Also (below) reset all bitmaps and
1855                  * stats in active history.
1856                  */
1857                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1858                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1859                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1860                      && (flush_interval_passed))) {
1861                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1862                                      lq_sta->total_failed,
1863                                      lq_sta->total_success,
1864                                      flush_interval_passed);
1865
1866                         /* Allow search for new mode */
1867                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1868                         lq_sta->total_failed = 0;
1869                         lq_sta->total_success = 0;
1870                         lq_sta->flush_timer = 0;
1871
1872                 /*
1873                  * Else if we've used this modulation mode enough repetitions
1874                  * (regardless of elapsed time or success/failure), reset
1875                  * history bitmaps and rate-specific stats for all rates in
1876                  * active table.
1877                  */
1878                 } else {
1879                         lq_sta->table_count++;
1880                         if (lq_sta->table_count >=
1881                             lq_sta->table_count_limit) {
1882                                 lq_sta->table_count = 0;
1883
1884                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
1885                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1886                                         rs_rate_scale_clear_window(
1887                                                 &(tbl->win[i]));
1888                         }
1889                 }
1890
1891                 /* If transitioning to allow "search", reset all history
1892                  * bitmaps and stats in active table (this will become the new
1893                  * "search" table). */
1894                 if (!lq_sta->stay_in_tbl) {
1895                         for (i = 0; i < IWL_RATE_COUNT; i++)
1896                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1897                 }
1898         }
1899 }
1900
1901 /*
1902  * setup rate table in uCode
1903  * return rate_n_flags as used in the table
1904  */
1905 static u32 rs_update_rate_tbl(struct iwl_priv *priv,
1906                                 struct iwl_lq_sta *lq_sta,
1907                                 struct iwl_scale_tbl_info *tbl,
1908                                 int index, u8 is_green)
1909 {
1910         u32 rate;
1911
1912         /* Update uCode's rate table. */
1913         rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
1914         rs_fill_link_cmd(priv, lq_sta, rate);
1915         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1916
1917         return rate;
1918 }
1919
1920 /*
1921  * Do rate scaling and search for new modulation mode.
1922  */
1923 static void rs_rate_scale_perform(struct iwl_priv *priv,
1924                                   struct sk_buff *skb,
1925                                   struct ieee80211_sta *sta,
1926                                   struct iwl_lq_sta *lq_sta)
1927 {
1928         struct ieee80211_hw *hw = priv->hw;
1929         struct ieee80211_conf *conf = &hw->conf;
1930         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1931         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1932         int low = IWL_RATE_INVALID;
1933         int high = IWL_RATE_INVALID;
1934         int index;
1935         int i;
1936         struct iwl_rate_scale_data *window = NULL;
1937         int current_tpt = IWL_INVALID_VALUE;
1938         int low_tpt = IWL_INVALID_VALUE;
1939         int high_tpt = IWL_INVALID_VALUE;
1940         u32 fail_count;
1941         s8 scale_action = 0;
1942         u16 rate_mask;
1943         u8 update_lq = 0;
1944         struct iwl_scale_tbl_info *tbl, *tbl1;
1945         u16 rate_scale_index_msk = 0;
1946         u32 rate;
1947         u8 is_green = 0;
1948         u8 active_tbl = 0;
1949         u8 done_search = 0;
1950         u16 high_low;
1951         s32 sr;
1952         u8 tid = MAX_TID_COUNT;
1953         struct iwl_tid_data *tid_data;
1954
1955         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
1956
1957         /* Send management frames and NO_ACK data using lowest rate. */
1958         /* TODO: this could probably be improved.. */
1959         if (!ieee80211_is_data(hdr->frame_control) ||
1960             info->flags & IEEE80211_TX_CTL_NO_ACK)
1961                 return;
1962
1963         if (!sta || !lq_sta)
1964                 return;
1965
1966         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1967
1968         tid = rs_tl_add_packet(lq_sta, hdr);
1969         if ((tid != MAX_TID_COUNT) && (lq_sta->tx_agg_tid_en & (1 << tid))) {
1970                 tid_data = &priv->stations[lq_sta->lq.sta_id].tid[tid];
1971                 if (tid_data->agg.state == IWL_AGG_OFF)
1972                         lq_sta->is_agg = 0;
1973                 else
1974                         lq_sta->is_agg = 1;
1975         } else
1976                 lq_sta->is_agg = 0;
1977
1978         /*
1979          * Select rate-scale / modulation-mode table to work with in
1980          * the rest of this function:  "search" if searching for better
1981          * modulation mode, or "active" if doing rate scaling within a mode.
1982          */
1983         if (!lq_sta->search_better_tbl)
1984                 active_tbl = lq_sta->active_tbl;
1985         else
1986                 active_tbl = 1 - lq_sta->active_tbl;
1987
1988         tbl = &(lq_sta->lq_info[active_tbl]);
1989         if (is_legacy(tbl->lq_type))
1990                 lq_sta->is_green = 0;
1991         else
1992                 lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
1993         is_green = lq_sta->is_green;
1994
1995         /* current tx rate */
1996         index = lq_sta->last_txrate_idx;
1997
1998         IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
1999                        tbl->lq_type);
2000
2001         /* rates available for this association, and for modulation mode */
2002         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
2003
2004         IWL_DEBUG_RATE(priv, "mask 0x%04X \n", rate_mask);
2005
2006         /* mask with station rate restriction */
2007         if (is_legacy(tbl->lq_type)) {
2008                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
2009                         /* supp_rates has no CCK bits in A mode */
2010                         rate_scale_index_msk = (u16) (rate_mask &
2011                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
2012                 else
2013                         rate_scale_index_msk = (u16) (rate_mask &
2014                                                       lq_sta->supp_rates);
2015
2016         } else
2017                 rate_scale_index_msk = rate_mask;
2018
2019         if (!rate_scale_index_msk)
2020                 rate_scale_index_msk = rate_mask;
2021
2022         if (!((1 << index) & rate_scale_index_msk)) {
2023                 IWL_ERR(priv, "Current Rate is not valid\n");
2024                 if (lq_sta->search_better_tbl) {
2025                         /* revert to active table if search table is not valid*/
2026                         tbl->lq_type = LQ_NONE;
2027                         lq_sta->search_better_tbl = 0;
2028                         tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2029                         /* get "active" rate info */
2030                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2031                         rate = rs_update_rate_tbl(priv, lq_sta,
2032                                                   tbl, index, is_green);
2033                 }
2034                 return;
2035         }
2036
2037         /* Get expected throughput table and history window for current rate */
2038         if (!tbl->expected_tpt) {
2039                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
2040                 return;
2041         }
2042
2043         /* force user max rate if set by user */
2044         if ((lq_sta->max_rate_idx != -1) &&
2045             (lq_sta->max_rate_idx < index)) {
2046                 index = lq_sta->max_rate_idx;
2047                 update_lq = 1;
2048                 window = &(tbl->win[index]);
2049                 goto lq_update;
2050         }
2051
2052         window = &(tbl->win[index]);
2053
2054         /*
2055          * If there is not enough history to calculate actual average
2056          * throughput, keep analyzing results of more tx frames, without
2057          * changing rate or mode (bypass most of the rest of this function).
2058          * Set up new rate table in uCode only if old rate is not supported
2059          * in current association (use new rate found above).
2060          */
2061         fail_count = window->counter - window->success_counter;
2062         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
2063                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
2064                 IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
2065                                "for index %d\n",
2066                                window->success_counter, window->counter, index);
2067
2068                 /* Can't calculate this yet; not enough history */
2069                 window->average_tpt = IWL_INVALID_VALUE;
2070
2071                 /* Should we stay with this modulation mode,
2072                  * or search for a new one? */
2073                 rs_stay_in_table(lq_sta);
2074
2075                 goto out;
2076         }
2077         /* Else we have enough samples; calculate estimate of
2078          * actual average throughput */
2079
2080         /* Sanity-check TPT calculations */
2081         BUG_ON(window->average_tpt != ((window->success_ratio *
2082                         tbl->expected_tpt[index] + 64) / 128));
2083
2084         /* If we are searching for better modulation mode, check success. */
2085         if (lq_sta->search_better_tbl &&
2086             (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI)) {
2087                 /* If good success, continue using the "search" mode;
2088                  * no need to send new link quality command, since we're
2089                  * continuing to use the setup that we've been trying. */
2090                 if (window->average_tpt > lq_sta->last_tpt) {
2091
2092                         IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
2093                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2094                                         window->success_ratio,
2095                                         window->average_tpt,
2096                                         lq_sta->last_tpt);
2097
2098                         if (!is_legacy(tbl->lq_type))
2099                                 lq_sta->enable_counter = 1;
2100
2101                         /* Swap tables; "search" becomes "active" */
2102                         lq_sta->active_tbl = active_tbl;
2103                         current_tpt = window->average_tpt;
2104
2105                 /* Else poor success; go back to mode in "active" table */
2106                 } else {
2107
2108                         IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
2109                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2110                                         window->success_ratio,
2111                                         window->average_tpt,
2112                                         lq_sta->last_tpt);
2113
2114                         /* Nullify "search" table */
2115                         tbl->lq_type = LQ_NONE;
2116
2117                         /* Revert to "active" table */
2118                         active_tbl = lq_sta->active_tbl;
2119                         tbl = &(lq_sta->lq_info[active_tbl]);
2120
2121                         /* Revert to "active" rate and throughput info */
2122                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2123                         current_tpt = lq_sta->last_tpt;
2124
2125                         /* Need to set up a new rate table in uCode */
2126                         update_lq = 1;
2127                 }
2128
2129                 /* Either way, we've made a decision; modulation mode
2130                  * search is done, allow rate adjustment next time. */
2131                 lq_sta->search_better_tbl = 0;
2132                 done_search = 1;        /* Don't switch modes below! */
2133                 goto lq_update;
2134         }
2135
2136         /* (Else) not in search of better modulation mode, try for better
2137          * starting rate, while staying in this mode. */
2138         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
2139                                         tbl->lq_type);
2140         low = high_low & 0xff;
2141         high = (high_low >> 8) & 0xff;
2142
2143         /* If user set max rate, dont allow higher than user constrain */
2144         if ((lq_sta->max_rate_idx != -1) &&
2145             (lq_sta->max_rate_idx < high))
2146                 high = IWL_RATE_INVALID;
2147
2148         sr = window->success_ratio;
2149
2150         /* Collect measured throughputs for current and adjacent rates */
2151         current_tpt = window->average_tpt;
2152         if (low != IWL_RATE_INVALID)
2153                 low_tpt = tbl->win[low].average_tpt;
2154         if (high != IWL_RATE_INVALID)
2155                 high_tpt = tbl->win[high].average_tpt;
2156
2157         scale_action = 0;
2158
2159         /* Too many failures, decrease rate */
2160         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
2161                 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
2162                 scale_action = -1;
2163
2164         /* No throughput measured yet for adjacent rates; try increase. */
2165         } else if ((low_tpt == IWL_INVALID_VALUE) &&
2166                    (high_tpt == IWL_INVALID_VALUE)) {
2167
2168                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
2169                         scale_action = 1;
2170                 else if (low != IWL_RATE_INVALID)
2171                         scale_action = 0;
2172         }
2173
2174         /* Both adjacent throughputs are measured, but neither one has better
2175          * throughput; we're using the best rate, don't change it! */
2176         else if ((low_tpt != IWL_INVALID_VALUE) &&
2177                  (high_tpt != IWL_INVALID_VALUE) &&
2178                  (low_tpt < current_tpt) &&
2179                  (high_tpt < current_tpt))
2180                 scale_action = 0;
2181
2182         /* At least one adjacent rate's throughput is measured,
2183          * and may have better performance. */
2184         else {
2185                 /* Higher adjacent rate's throughput is measured */
2186                 if (high_tpt != IWL_INVALID_VALUE) {
2187                         /* Higher rate has better throughput */
2188                         if (high_tpt > current_tpt &&
2189                                         sr >= IWL_RATE_INCREASE_TH) {
2190                                 scale_action = 1;
2191                         } else {
2192                                 scale_action = 0;
2193                         }
2194
2195                 /* Lower adjacent rate's throughput is measured */
2196                 } else if (low_tpt != IWL_INVALID_VALUE) {
2197                         /* Lower rate has better throughput */
2198                         if (low_tpt > current_tpt) {
2199                                 IWL_DEBUG_RATE(priv,
2200                                     "decrease rate because of low tpt\n");
2201                                 scale_action = -1;
2202                         } else if (sr >= IWL_RATE_INCREASE_TH) {
2203                                 scale_action = 1;
2204                         }
2205                 }
2206         }
2207
2208         /* Sanity check; asked for decrease, but success rate or throughput
2209          * has been good at old rate.  Don't change it. */
2210         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
2211                     ((sr > IWL_RATE_HIGH_TH) ||
2212                      (current_tpt > (100 * tbl->expected_tpt[low]))))
2213                 scale_action = 0;
2214         if (!iwl_ht_enabled(priv) && !is_legacy(tbl->lq_type))
2215                 scale_action = -1;
2216         if (iwl_tx_ant_restriction(priv) != IWL_ANT_OK_MULTI &&
2217                 (is_mimo2(tbl->lq_type) || is_mimo3(tbl->lq_type)))
2218                 scale_action = -1;
2219         switch (scale_action) {
2220         case -1:
2221                 /* Decrease starting rate, update uCode's rate table */
2222                 if (low != IWL_RATE_INVALID) {
2223                         update_lq = 1;
2224                         index = low;
2225                 }
2226
2227                 break;
2228         case 1:
2229                 /* Increase starting rate, update uCode's rate table */
2230                 if (high != IWL_RATE_INVALID) {
2231                         update_lq = 1;
2232                         index = high;
2233                 }
2234
2235                 break;
2236         case 0:
2237                 /* No change */
2238         default:
2239                 break;
2240         }
2241
2242         IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
2243                     "high %d type %d\n",
2244                      index, scale_action, low, high, tbl->lq_type);
2245
2246 lq_update:
2247         /* Replace uCode's rate table for the destination station. */
2248         if (update_lq)
2249                 rate = rs_update_rate_tbl(priv, lq_sta,
2250                                           tbl, index, is_green);
2251
2252         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI) {
2253                 /* Should we stay with this modulation mode,
2254                  * or search for a new one? */
2255                 rs_stay_in_table(lq_sta);
2256         }
2257         /*
2258          * Search for new modulation mode if we're:
2259          * 1)  Not changing rates right now
2260          * 2)  Not just finishing up a search
2261          * 3)  Allowing a new search
2262          */
2263         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
2264                 /* Save current throughput to compare with "search" throughput*/
2265                 lq_sta->last_tpt = current_tpt;
2266
2267                 /* Select a new "search" modulation mode to try.
2268                  * If one is found, set up the new "search" table. */
2269                 if (is_legacy(tbl->lq_type))
2270                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
2271                 else if (is_siso(tbl->lq_type))
2272                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2273                 else if (is_mimo2(tbl->lq_type))
2274                         rs_move_mimo2_to_other(priv, lq_sta, conf, sta, index);
2275                 else
2276                         rs_move_mimo3_to_other(priv, lq_sta, conf, sta, index);
2277
2278                 /* If new "search" mode was selected, set up in uCode table */
2279                 if (lq_sta->search_better_tbl) {
2280                         /* Access the "search" table, clear its history. */
2281                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2282                         for (i = 0; i < IWL_RATE_COUNT; i++)
2283                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2284
2285                         /* Use new "search" start rate */
2286                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2287
2288                         IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
2289                                      tbl->current_rate, index);
2290                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
2291                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2292                 } else
2293                         done_search = 1;
2294         }
2295
2296         if (done_search && !lq_sta->stay_in_tbl) {
2297                 /* If the "active" (non-search) mode was legacy,
2298                  * and we've tried switching antennas,
2299                  * but we haven't been able to try HT modes (not available),
2300                  * stay with best antenna legacy modulation for a while
2301                  * before next round of mode comparisons. */
2302                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2303                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2304                     lq_sta->action_counter > tbl1->max_search) {
2305                         IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2306                         rs_set_stay_in_table(priv, 1, lq_sta);
2307                 }
2308
2309                 /* If we're in an HT mode, and all 3 mode switch actions
2310                  * have been tried and compared, stay in this best modulation
2311                  * mode for a while before next round of mode comparisons. */
2312                 if (lq_sta->enable_counter &&
2313                     (lq_sta->action_counter >= tbl1->max_search) &&
2314                     iwl_ht_enabled(priv)) {
2315                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2316                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2317                             (tid != MAX_TID_COUNT)) {
2318                                 tid_data =
2319                                    &priv->stations[lq_sta->lq.sta_id].tid[tid];
2320                                 if (tid_data->agg.state == IWL_AGG_OFF) {
2321                                         IWL_DEBUG_RATE(priv,
2322                                                        "try to aggregate tid %d\n",
2323                                                        tid);
2324                                         rs_tl_turn_on_agg(priv, tid,
2325                                                           lq_sta, sta);
2326                                 }
2327                         }
2328                         rs_set_stay_in_table(priv, 0, lq_sta);
2329                 }
2330         }
2331
2332 out:
2333         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2334         i = index;
2335         lq_sta->last_txrate_idx = i;
2336
2337         return;
2338 }
2339
2340
2341 static void rs_initialize_lq(struct iwl_priv *priv,
2342                              struct ieee80211_conf *conf,
2343                              struct ieee80211_sta *sta,
2344                              struct iwl_lq_sta *lq_sta)
2345 {
2346         struct iwl_scale_tbl_info *tbl;
2347         int rate_idx;
2348         int i;
2349         u32 rate;
2350         u8 use_green = rs_use_green(sta, &priv->current_ht_config);
2351         u8 active_tbl = 0;
2352         u8 valid_tx_ant;
2353
2354         if (!sta || !lq_sta)
2355                 goto out;
2356
2357         i = lq_sta->last_txrate_idx;
2358
2359         if ((lq_sta->lq.sta_id == 0xff) &&
2360             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2361                 goto out;
2362
2363         valid_tx_ant = priv->hw_params.valid_tx_ant;
2364
2365         if (!lq_sta->search_better_tbl)
2366                 active_tbl = lq_sta->active_tbl;
2367         else
2368                 active_tbl = 1 - lq_sta->active_tbl;
2369
2370         tbl = &(lq_sta->lq_info[active_tbl]);
2371
2372         if ((i < 0) || (i >= IWL_RATE_COUNT))
2373                 i = 0;
2374
2375         rate = iwl_rates[i].plcp;
2376         tbl->ant_type = first_antenna(valid_tx_ant);
2377         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2378
2379         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2380                 rate |= RATE_MCS_CCK_MSK;
2381
2382         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2383         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2384             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2385
2386         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2387         tbl->current_rate = rate;
2388         rs_set_expected_tpt_table(lq_sta, tbl);
2389         rs_fill_link_cmd(NULL, lq_sta, rate);
2390         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2391  out:
2392         return;
2393 }
2394
2395 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2396                         struct ieee80211_tx_rate_control *txrc)
2397 {
2398
2399         struct sk_buff *skb = txrc->skb;
2400         struct ieee80211_supported_band *sband = txrc->sband;
2401         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2402         struct ieee80211_conf *conf = &priv->hw->conf;
2403         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2404         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2405         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2406         struct iwl_lq_sta *lq_sta = priv_sta;
2407         int rate_idx;
2408
2409         IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2410
2411         /* Get max rate if user set max rate */
2412         if (lq_sta) {
2413                 lq_sta->max_rate_idx = txrc->max_rate_idx;
2414                 if ((sband->band == IEEE80211_BAND_5GHZ) &&
2415                     (lq_sta->max_rate_idx != -1))
2416                         lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2417                 if ((lq_sta->max_rate_idx < 0) ||
2418                     (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2419                         lq_sta->max_rate_idx = -1;
2420         }
2421
2422         /* Send management frames and NO_ACK data using lowest rate. */
2423         if (rate_control_send_low(sta, priv_sta, txrc))
2424                 return;
2425
2426         rate_idx  = lq_sta->last_txrate_idx;
2427
2428         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2429             !lq_sta->ibss_sta_added) {
2430                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2431
2432                 if (sta_id == IWL_INVALID_STATION) {
2433                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
2434                                        hdr->addr1);
2435                         sta_id = iwl_add_station(priv, hdr->addr1,
2436                                                 false, CMD_ASYNC, ht_cap);
2437                 }
2438                 if ((sta_id != IWL_INVALID_STATION)) {
2439                         lq_sta->lq.sta_id = sta_id;
2440                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2441                         lq_sta->ibss_sta_added = 1;
2442                         rs_initialize_lq(priv, conf, sta, lq_sta);
2443                 }
2444         }
2445
2446         if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2447                 rate_idx -= IWL_FIRST_OFDM_RATE;
2448                 /* 6M and 9M shared same MCS index */
2449                 rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2450                 if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2451                     IWL_RATE_MIMO3_6M_PLCP)
2452                         rate_idx = rate_idx + (2 * MCS_INDEX_PER_STREAM);
2453                 else if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2454                          IWL_RATE_MIMO2_6M_PLCP)
2455                         rate_idx = rate_idx + MCS_INDEX_PER_STREAM;
2456                 info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2457                 if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2458                         info->control.rates[0].flags |= IEEE80211_TX_RC_SHORT_GI;
2459                 if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2460                         info->control.rates[0].flags |= IEEE80211_TX_RC_DUP_DATA;
2461                 if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2462                         info->control.rates[0].flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
2463                 if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2464                         info->control.rates[0].flags |= IEEE80211_TX_RC_GREEN_FIELD;
2465         } else {
2466                 /* Check for invalid rates */
2467                 if ((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT_LEGACY) ||
2468                                 ((sband->band == IEEE80211_BAND_5GHZ) &&
2469                                  (rate_idx < IWL_FIRST_OFDM_RATE)))
2470                         rate_idx = rate_lowest_index(sband, sta);
2471                 /* On valid 5 GHz rate, adjust index */
2472                 else if (sband->band == IEEE80211_BAND_5GHZ)
2473                         rate_idx -= IWL_FIRST_OFDM_RATE;
2474                 info->control.rates[0].flags = 0;
2475         }
2476         info->control.rates[0].idx = rate_idx;
2477
2478 }
2479
2480 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2481                           gfp_t gfp)
2482 {
2483         struct iwl_lq_sta *lq_sta;
2484         struct iwl_station_priv *sta_priv = (struct iwl_station_priv *) sta->drv_priv;
2485         struct iwl_priv *priv;
2486
2487         priv = (struct iwl_priv *)priv_rate;
2488         IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2489
2490         lq_sta = &sta_priv->lq_sta;
2491
2492         return lq_sta;
2493 }
2494
2495 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2496                          struct ieee80211_sta *sta, void *priv_sta)
2497 {
2498         int i, j;
2499         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2500         struct ieee80211_conf *conf = &priv->hw->conf;
2501         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2502         struct iwl_lq_sta *lq_sta = priv_sta;
2503
2504         lq_sta->lq.sta_id = 0xff;
2505
2506         for (j = 0; j < LQ_SIZE; j++)
2507                 for (i = 0; i < IWL_RATE_COUNT; i++)
2508                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2509
2510         lq_sta->flush_timer = 0;
2511         lq_sta->supp_rates = sta->supp_rates[sband->band];
2512         for (j = 0; j < LQ_SIZE; j++)
2513                 for (i = 0; i < IWL_RATE_COUNT; i++)
2514                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2515
2516         IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init ***\n");
2517         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2518          * the lowest or the highest rate.. Could consider using RSSI from
2519          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2520          * after assoc.. */
2521
2522         lq_sta->ibss_sta_added = 0;
2523         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2524                 u8 sta_id = iwl_find_station(priv,
2525                                                                 sta->addr);
2526
2527                 /* for IBSS the call are from tasklet */
2528                 IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2529
2530                 if (sta_id == IWL_INVALID_STATION) {
2531                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2532                         sta_id = iwl_add_station(priv, sta->addr, false,
2533                                                 CMD_ASYNC, ht_cap);
2534                 }
2535                 if ((sta_id != IWL_INVALID_STATION)) {
2536                         lq_sta->lq.sta_id = sta_id;
2537                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2538                 }
2539                 /* FIXME: this is w/a remove it later */
2540                 priv->assoc_station_added = 1;
2541         }
2542
2543         lq_sta->is_dup = 0;
2544         lq_sta->max_rate_idx = -1;
2545         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2546         lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2547         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2548         lq_sta->active_rate_basic = priv->active_rate_basic;
2549         lq_sta->band = priv->band;
2550         /*
2551          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2552          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2553          */
2554         lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
2555         lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
2556         lq_sta->active_siso_rate &= ~((u16)0x2);
2557         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2558
2559         /* Same here */
2560         lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
2561         lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
2562         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2563         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2564
2565         lq_sta->active_mimo3_rate = ht_cap->mcs.rx_mask[2] << 1;
2566         lq_sta->active_mimo3_rate |= ht_cap->mcs.rx_mask[2] & 0x1;
2567         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2568         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2569
2570         IWL_DEBUG_RATE(priv, "SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2571                      lq_sta->active_siso_rate,
2572                      lq_sta->active_mimo2_rate,
2573                      lq_sta->active_mimo3_rate);
2574
2575         /* These values will be overridden later */
2576         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2577         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2578
2579         /* as default allow aggregation for all tids */
2580         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2581         lq_sta->drv = priv;
2582
2583         /* Set last_txrate_idx to lowest rate */
2584         lq_sta->last_txrate_idx = rate_lowest_index(sband, sta);
2585         if (sband->band == IEEE80211_BAND_5GHZ)
2586                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2587         lq_sta->is_agg = 0;
2588
2589         rs_initialize_lq(priv, conf, sta, lq_sta);
2590 }
2591
2592 static void rs_fill_link_cmd(struct iwl_priv *priv,
2593                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2594 {
2595         struct iwl_scale_tbl_info tbl_type;
2596         int index = 0;
2597         int rate_idx;
2598         int repeat_rate = 0;
2599         u8 ant_toggle_cnt = 0;
2600         u8 use_ht_possible = 1;
2601         u8 valid_tx_ant = 0;
2602         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2603
2604         /* Override starting rate (index 0) if needed for debug purposes */
2605         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2606
2607         /* Interpret new_rate (rate_n_flags) */
2608         memset(&tbl_type, 0, sizeof(tbl_type));
2609         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2610                                   &tbl_type, &rate_idx);
2611
2612         /* How many times should we repeat the initial rate? */
2613         if (is_legacy(tbl_type.lq_type)) {
2614                 ant_toggle_cnt = 1;
2615                 repeat_rate = IWL_NUMBER_TRY;
2616         } else {
2617                 repeat_rate = IWL_HT_NUMBER_TRY;
2618         }
2619
2620         lq_cmd->general_params.mimo_delimiter =
2621                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2622
2623         /* Fill 1st table entry (index 0) */
2624         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2625
2626         if (num_of_ant(tbl_type.ant_type) == 1) {
2627                 lq_cmd->general_params.single_stream_ant_msk =
2628                                                 tbl_type.ant_type;
2629         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2630                 lq_cmd->general_params.dual_stream_ant_msk =
2631                                                 tbl_type.ant_type;
2632         } /* otherwise we don't modify the existing value */
2633
2634         index++;
2635         repeat_rate--;
2636
2637         if (priv)
2638                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2639
2640         /* Fill rest of rate table */
2641         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2642                 /* Repeat initial/next rate.
2643                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2644                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2645                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2646                         if (is_legacy(tbl_type.lq_type)) {
2647                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2648                                         ant_toggle_cnt++;
2649                                 else if (priv &&
2650                                          rs_toggle_antenna(valid_tx_ant,
2651                                                         &new_rate, &tbl_type))
2652                                         ant_toggle_cnt = 1;
2653 }
2654
2655                         /* Override next rate if needed for debug purposes */
2656                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2657
2658                         /* Fill next table entry */
2659                         lq_cmd->rs_table[index].rate_n_flags =
2660                                         cpu_to_le32(new_rate);
2661                         repeat_rate--;
2662                         index++;
2663                 }
2664
2665                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2666                                                 &rate_idx);
2667
2668                 /* Indicate to uCode which entries might be MIMO.
2669                  * If initial rate was MIMO, this will finally end up
2670                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2671                 if (is_mimo(tbl_type.lq_type))
2672                         lq_cmd->general_params.mimo_delimiter = index;
2673
2674                 /* Get next rate */
2675                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2676                                              use_ht_possible);
2677
2678                 /* How many times should we repeat the next rate? */
2679                 if (is_legacy(tbl_type.lq_type)) {
2680                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2681                                 ant_toggle_cnt++;
2682                         else if (priv &&
2683                                  rs_toggle_antenna(valid_tx_ant,
2684                                                    &new_rate, &tbl_type))
2685                                 ant_toggle_cnt = 1;
2686
2687                         repeat_rate = IWL_NUMBER_TRY;
2688                 } else {
2689                         repeat_rate = IWL_HT_NUMBER_TRY;
2690                 }
2691
2692                 /* Don't allow HT rates after next pass.
2693                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2694                 use_ht_possible = 0;
2695
2696                 /* Override next rate if needed for debug purposes */
2697                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2698
2699                 /* Fill next table entry */
2700                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2701
2702                 index++;
2703                 repeat_rate--;
2704         }
2705
2706         lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
2707         lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2708         lq_cmd->agg_params.agg_time_limit =
2709                 cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2710 }
2711
2712 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2713 {
2714         return hw->priv;
2715 }
2716 /* rate scale requires free function to be implemented */
2717 static void rs_free(void *priv_rate)
2718 {
2719         return;
2720 }
2721
2722 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2723                         void *priv_sta)
2724 {
2725         struct iwl_priv *priv __maybe_unused = priv_r;
2726
2727         IWL_DEBUG_RATE(priv, "enter\n");
2728         IWL_DEBUG_RATE(priv, "leave\n");
2729 }
2730
2731
2732 #ifdef CONFIG_MAC80211_DEBUGFS
2733 static int open_file_generic(struct inode *inode, struct file *file)
2734 {
2735         file->private_data = inode->i_private;
2736         return 0;
2737 }
2738 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2739                              u32 *rate_n_flags, int index)
2740 {
2741         struct iwl_priv *priv;
2742         u8 valid_tx_ant;
2743         u8 ant_sel_tx;
2744
2745         priv = lq_sta->drv;
2746         valid_tx_ant = priv->hw_params.valid_tx_ant;
2747         if (lq_sta->dbg_fixed_rate) {
2748                 ant_sel_tx =
2749                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2750                   >> RATE_MCS_ANT_POS);
2751                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2752                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2753                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2754                 } else {
2755                         lq_sta->dbg_fixed_rate = 0;
2756                         IWL_ERR(priv,
2757                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2758                             ant_sel_tx, valid_tx_ant);
2759                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2760                 }
2761         } else {
2762                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2763         }
2764 }
2765
2766 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2767                         const char __user *user_buf, size_t count, loff_t *ppos)
2768 {
2769         struct iwl_lq_sta *lq_sta = file->private_data;
2770         struct iwl_priv *priv;
2771         char buf[64];
2772         int buf_size;
2773         u32 parsed_rate;
2774
2775         priv = lq_sta->drv;
2776         memset(buf, 0, sizeof(buf));
2777         buf_size = min(count, sizeof(buf) -  1);
2778         if (copy_from_user(buf, user_buf, buf_size))
2779                 return -EFAULT;
2780
2781         if (sscanf(buf, "%x", &parsed_rate) == 1)
2782                 lq_sta->dbg_fixed_rate = parsed_rate;
2783         else
2784                 lq_sta->dbg_fixed_rate = 0;
2785
2786         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2787         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2788         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2789         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2790
2791         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2792                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2793
2794         if (lq_sta->dbg_fixed_rate) {
2795                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2796                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2797         }
2798
2799         return count;
2800 }
2801
2802 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2803                         char __user *user_buf, size_t count, loff_t *ppos)
2804 {
2805         char *buff;
2806         int desc = 0;
2807         int i = 0;
2808         int index = 0;
2809         ssize_t ret;
2810
2811         struct iwl_lq_sta *lq_sta = file->private_data;
2812         struct iwl_priv *priv;
2813         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2814
2815         priv = lq_sta->drv;
2816         buff = kmalloc(1024, GFP_KERNEL);
2817         if (!buff)
2818                 return -ENOMEM;
2819
2820         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2821         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2822                         lq_sta->total_failed, lq_sta->total_success,
2823                         lq_sta->active_legacy_rate);
2824         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2825                         lq_sta->dbg_fixed_rate);
2826         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2827             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2828             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2829             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2830         desc += sprintf(buff+desc, "lq type %s\n",
2831            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2832         if (is_Ht(tbl->lq_type)) {
2833                 desc += sprintf(buff+desc, " %s",
2834                    (is_siso(tbl->lq_type)) ? "SISO" :
2835                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2836                    desc += sprintf(buff+desc, " %s",
2837                    (tbl->is_ht40) ? "40MHz" : "20MHz");
2838                    desc += sprintf(buff+desc, " %s %s %s\n", (tbl->is_SGI) ? "SGI" : "",
2839                    (lq_sta->is_green) ? "GF enabled" : "",
2840                    (lq_sta->is_agg) ? "AGG on" : "");
2841         }
2842         desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2843                 lq_sta->last_rate_n_flags);
2844         desc += sprintf(buff+desc, "general:"
2845                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2846                 lq_sta->lq.general_params.flags,
2847                 lq_sta->lq.general_params.mimo_delimiter,
2848                 lq_sta->lq.general_params.single_stream_ant_msk,
2849                 lq_sta->lq.general_params.dual_stream_ant_msk);
2850
2851         desc += sprintf(buff+desc, "agg:"
2852                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2853                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2854                         lq_sta->lq.agg_params.agg_dis_start_th,
2855                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2856
2857         desc += sprintf(buff+desc,
2858                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2859                         lq_sta->lq.general_params.start_rate_index[0],
2860                         lq_sta->lq.general_params.start_rate_index[1],
2861                         lq_sta->lq.general_params.start_rate_index[2],
2862                         lq_sta->lq.general_params.start_rate_index[3]);
2863
2864         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2865                 index = iwl_hwrate_to_plcp_idx(
2866                         le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2867                 if (is_legacy(tbl->lq_type)) {
2868                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2869                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2870                                 iwl_rate_mcs[index].mbps);
2871                 } else {
2872                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps (%s)\n",
2873                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2874                                 iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
2875                 }
2876         }
2877
2878         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2879         kfree(buff);
2880         return ret;
2881 }
2882
2883 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2884         .write = rs_sta_dbgfs_scale_table_write,
2885         .read = rs_sta_dbgfs_scale_table_read,
2886         .open = open_file_generic,
2887 };
2888 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2889                         char __user *user_buf, size_t count, loff_t *ppos)
2890 {
2891         char *buff;
2892         int desc = 0;
2893         int i, j;
2894         ssize_t ret;
2895
2896         struct iwl_lq_sta *lq_sta = file->private_data;
2897
2898         buff = kmalloc(1024, GFP_KERNEL);
2899         if (!buff)
2900                 return -ENOMEM;
2901
2902         for (i = 0; i < LQ_SIZE; i++) {
2903                 desc += sprintf(buff+desc,
2904                                 "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
2905                                 "rate=0x%X\n",
2906                                 lq_sta->active_tbl == i ? "*" : "x",
2907                                 lq_sta->lq_info[i].lq_type,
2908                                 lq_sta->lq_info[i].is_SGI,
2909                                 lq_sta->lq_info[i].is_ht40,
2910                                 lq_sta->lq_info[i].is_dup,
2911                                 lq_sta->is_green,
2912                                 lq_sta->lq_info[i].current_rate);
2913                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2914                         desc += sprintf(buff+desc,
2915                                 "counter=%d success=%d %%=%d\n",
2916                                 lq_sta->lq_info[i].win[j].counter,
2917                                 lq_sta->lq_info[i].win[j].success_counter,
2918                                 lq_sta->lq_info[i].win[j].success_ratio);
2919                 }
2920         }
2921         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2922         kfree(buff);
2923         return ret;
2924 }
2925
2926 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2927         .read = rs_sta_dbgfs_stats_table_read,
2928         .open = open_file_generic,
2929 };
2930
2931 static ssize_t rs_sta_dbgfs_rate_scale_data_read(struct file *file,
2932                         char __user *user_buf, size_t count, loff_t *ppos)
2933 {
2934         char buff[120];
2935         int desc = 0;
2936         ssize_t ret;
2937
2938         struct iwl_lq_sta *lq_sta = file->private_data;
2939         struct iwl_priv *priv;
2940         struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
2941
2942         priv = lq_sta->drv;
2943
2944         if (is_Ht(tbl->lq_type))
2945                 desc += sprintf(buff+desc,
2946                                 "Bit Rate= %d Mb/s\n",
2947                                 tbl->expected_tpt[lq_sta->last_txrate_idx]);
2948         else
2949                 desc += sprintf(buff+desc,
2950                                 "Bit Rate= %d Mb/s\n",
2951                                 iwl_rates[lq_sta->last_txrate_idx].ieee >> 1);
2952         desc += sprintf(buff+desc,
2953                         "Signal Level= %d dBm\tNoise Level= %d dBm\n",
2954                         priv->last_rx_rssi, priv->last_rx_noise);
2955         desc += sprintf(buff+desc,
2956                         "Tsf= 0x%llx\tBeacon time= 0x%08X\n",
2957                         priv->last_tsf, priv->last_beacon_time);
2958
2959         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2960         return ret;
2961 }
2962
2963 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
2964         .read = rs_sta_dbgfs_rate_scale_data_read,
2965         .open = open_file_generic,
2966 };
2967
2968 static void rs_add_debugfs(void *priv, void *priv_sta,
2969                                         struct dentry *dir)
2970 {
2971         struct iwl_lq_sta *lq_sta = priv_sta;
2972         lq_sta->rs_sta_dbgfs_scale_table_file =
2973                 debugfs_create_file("rate_scale_table", S_IRUSR | S_IWUSR, dir,
2974                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2975         lq_sta->rs_sta_dbgfs_stats_table_file =
2976                 debugfs_create_file("rate_stats_table", S_IRUSR, dir,
2977                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2978         lq_sta->rs_sta_dbgfs_rate_scale_data_file =
2979                 debugfs_create_file("rate_scale_data", S_IRUSR, dir,
2980                         lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
2981         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2982                 debugfs_create_u8("tx_agg_tid_enable", S_IRUSR | S_IWUSR, dir,
2983                 &lq_sta->tx_agg_tid_en);
2984
2985 }
2986
2987 static void rs_remove_debugfs(void *priv, void *priv_sta)
2988 {
2989         struct iwl_lq_sta *lq_sta = priv_sta;
2990         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2991         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2992         debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
2993         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2994 }
2995 #endif
2996
2997 static struct rate_control_ops rs_ops = {
2998         .module = NULL,
2999         .name = RS_NAME,
3000         .tx_status = rs_tx_status,
3001         .get_rate = rs_get_rate,
3002         .rate_init = rs_rate_init,
3003         .alloc = rs_alloc,
3004         .free = rs_free,
3005         .alloc_sta = rs_alloc_sta,
3006         .free_sta = rs_free_sta,
3007 #ifdef CONFIG_MAC80211_DEBUGFS
3008         .add_sta_debugfs = rs_add_debugfs,
3009         .remove_sta_debugfs = rs_remove_debugfs,
3010 #endif
3011 };
3012
3013 int iwlagn_rate_control_register(void)
3014 {
3015         return ieee80211_rate_control_register(&rs_ops);
3016 }
3017
3018 void iwlagn_rate_control_unregister(void)
3019 {
3020         ieee80211_rate_control_unregister(&rs_ops);
3021 }
3022