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  * rs_collect_tx_data - Update the success/failure sliding window
 350  *
 351  * We keep a sliding window of the last 62 packets transmitted
 352  * at this rate.  window->data contains the bitmask of successful
 353  * packets.
 354  */
 355 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
 356                               int scale_index, s32 tpt, int attempts,
 357                               int successes)
 358 {
 359         struct iwl_rate_scale_data *window = NULL;
 360         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 361         s32 fail_count;
 362
 363         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 364                 return -EINVAL;
 365
 366         /* Select window for current tx bit rate */
 367         window = &(windows[scale_index]);
 368
 369         /*
 370          * Keep track of only the latest 62 tx frame attempts in this rate's
 371          * history window; anything older isn't really relevant any more.
 372          * If we have filled up the sliding window, drop the oldest attempt;
 373          * if the oldest attempt (highest bit in bitmap) shows "success",
 374          * subtract "1" from the success counter (this is the main reason
 375          * we keep these bitmaps!).
 376          */
 377         while (attempts > 0) {
 378                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 379
 380                         /* remove earliest */
 381                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 382
 383                         if (window->data & mask) {
 384                                 window->data &= ~mask;
 385                                 window->success_counter--;
 386                         }
 387                 }
 388
 389                 /* Increment frames-attempted counter */
 390                 window->counter++;
 391
 392                 /* Shift bitmap by one frame to throw away oldest history */
 393                 window->data <<= 1;
 394
 395                 /* Mark the most recent #successes attempts as successful */
 396                 if (successes > 0) {
 397                         window->success_counter++;
 398                         window->data |= 0x1;
 399                         successes--;
 400                 }
 401
 402                 attempts--;
 403         }
 404
 405         /* Calculate current success ratio, avoid divide-by-0! */
 406         if (window->counter > 0)
 407                 window->success_ratio = 128 * (100 * window->success_counter)
 408                                         / window->counter;
 409         else
 410                 window->success_ratio = IWL_INVALID_VALUE;
 411
 412         fail_count = window->counter - window->success_counter;
 413
 414         /* Calculate average throughput, if we have enough history. */
 415         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 416             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 417                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 418         else
 419                 window->average_tpt = IWL_INVALID_VALUE;
 420
 421         /* Tag this window as having been updated */
 422         window->stamp = jiffies;
 423
 424         return 0;
 425 }
 426
 427 /*
 428  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 429  */
 430 /* FIXME:RS:remove this function and put the flags statically in the table */
 431 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 432                                  struct iwl_scale_tbl_info *tbl,
 433                                  int index, u8 use_green)
 434 {
 435         u32 rate_n_flags = 0;
 436
 437         if (is_legacy(tbl->lq_type)) {
 438                 rate_n_flags = iwl_rates[index].plcp;
 439                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 440                         rate_n_flags |= RATE_MCS_CCK_MSK;
 441
 442         } else if (is_Ht(tbl->lq_type)) {
 443                 if (index > IWL_LAST_OFDM_RATE) {
 444                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 445                         index = IWL_LAST_OFDM_RATE;
 446                 }
 447                 rate_n_flags = RATE_MCS_HT_MSK;
 448
 449                 if (is_siso(tbl->lq_type))
 450                         rate_n_flags |= iwl_rates[index].plcp_siso;
 451                 else if (is_mimo2(tbl->lq_type))
 452                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 453                 else
 454                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 455         } else {
 456                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 457         }
 458
 459         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 460                                                      RATE_MCS_ANT_ABC_MSK);
 461
 462         if (is_Ht(tbl->lq_type)) {
 463                 if (tbl->is_ht40) {
 464                         if (tbl->is_dup)
 465                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 466                         else
 467                                 rate_n_flags |= RATE_MCS_HT40_MSK;
 468                 }
 469                 if (tbl->is_SGI)
 470                         rate_n_flags |= RATE_MCS_SGI_MSK;
 471
 472                 if (use_green) {
 473                         rate_n_flags |= RATE_MCS_GF_MSK;
 474                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 475                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 476                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 477                         }
 478                 }
 479         }
 480         return rate_n_flags;
 481 }
 482
 483 /*
 484  * Interpret uCode API's rate_n_flags format,
 485  * fill "search" or "active" tx mode table.
 486  */
 487 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 488                                     enum ieee80211_band band,
 489                                     struct iwl_scale_tbl_info *tbl,
 490                                     int *rate_idx)
 491 {
 492         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 493         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 494         u8 mcs;
 495
 496         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 497
 498         if (*rate_idx  == IWL_RATE_INVALID) {
 499                 *rate_idx = -1;
 500                 return -EINVAL;
 501         }
 502         tbl->is_SGI = 0;        /* default legacy setup */
 503         tbl->is_ht40 = 0;
 504         tbl->is_dup = 0;
 505         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 506         tbl->lq_type = LQ_NONE;
 507         tbl->max_search = IWL_MAX_SEARCH;
 508
 509         /* legacy rate format */
 510         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 511                 if (num_of_ant == 1) {
 512                         if (band == IEEE80211_BAND_5GHZ)
 513                                 tbl->lq_type = LQ_A;
 514                         else
 515                                 tbl->lq_type = LQ_G;
 516                 }
 517         /* HT rate format */
 518         } else {
 519                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 520                         tbl->is_SGI = 1;
 521
 522                 if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
 523                     (rate_n_flags & RATE_MCS_DUP_MSK))
 524                         tbl->is_ht40 = 1;
 525
 526                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 527                         tbl->is_dup = 1;
 528
 529                 mcs = rs_extract_rate(rate_n_flags);
 530
 531                 /* SISO */
 532                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 533                         if (num_of_ant == 1)
 534                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 535                 /* MIMO2 */
 536                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 537                         if (num_of_ant == 2)
 538                                 tbl->lq_type = LQ_MIMO2;
 539                 /* MIMO3 */
 540                 } else {
 541                         if (num_of_ant == 3) {
 542                                 tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
 543                                 tbl->lq_type = LQ_MIMO3;
 544                         }
 545                 }
 546         }
 547         return 0;
 548 }
 549
 550 /* switch to another antenna/antennas and return 1 */
 551 /* if no other valid antenna found, return 0 */
 552 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 553                              struct iwl_scale_tbl_info *tbl)
 554 {
 555         u8 new_ant_type;
 556
 557         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 558                 return 0;
 559
 560         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 561                 return 0;
 562
 563         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 564
 565         while ((new_ant_type != tbl->ant_type) &&
 566                !rs_is_valid_ant(valid_ant, new_ant_type))
 567                 new_ant_type = ant_toggle_lookup[new_ant_type];
 568
 569         if (new_ant_type == tbl->ant_type)
 570                 return 0;
 571
 572         tbl->ant_type = new_ant_type;
 573         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 574         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 575         return 1;
 576 }
 577
 578 /**
 579  * Green-field mode is valid if the station supports it and
 580  * there are no non-GF stations present in the BSS.
 581  */
 582 static inline u8 rs_use_green(struct ieee80211_sta *sta,
 583                               struct iwl_ht_config *ht_conf)
 584 {
 585         return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
 586                 !(ht_conf->non_GF_STA_present);
 587 }
 588
 589 /**
 590  * rs_get_supported_rates - get the available rates
 591  *
 592  * if management frame or broadcast frame only return
 593  * basic available rates.
 594  *
 595  */
 596 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 597                                   struct ieee80211_hdr *hdr,
 598                                   enum iwl_table_type rate_type)
 599 {
 600         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 601             lq_sta->active_rate_basic)
 602                 return lq_sta->active_rate_basic;
 603
 604         if (is_legacy(rate_type)) {
 605                 return lq_sta->active_legacy_rate;
 606         } else {
 607                 if (is_siso(rate_type))
 608                         return lq_sta->active_siso_rate;
 609                 else if (is_mimo2(rate_type))
 610                         return lq_sta->active_mimo2_rate;
 611                 else
 612                         return lq_sta->active_mimo3_rate;
 613         }
 614 }
 615
 616 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 617                                 int rate_type)
 618 {
 619         u8 high = IWL_RATE_INVALID;
 620         u8 low = IWL_RATE_INVALID;
 621
 622         /* 802.11A or ht walks to the next literal adjacent rate in
 623          * the rate table */
 624         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 625                 int i;
 626                 u32 mask;
 627
 628                 /* Find the previous rate that is in the rate mask */
 629                 i = index - 1;
 630                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 631                         if (rate_mask & mask) {
 632                                 low = i;
 633                                 break;
 634                         }
 635                 }
 636
 637                 /* Find the next rate that is in the rate mask */
 638                 i = index + 1;
 639                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 640                         if (rate_mask & mask) {
 641                                 high = i;
 642                                 break;
 643                         }
 644                 }
 645
 646                 return (high << 8) | low;
 647         }
 648
 649         low = index;
 650         while (low != IWL_RATE_INVALID) {
 651                 low = iwl_rates[low].prev_rs;
 652                 if (low == IWL_RATE_INVALID)
 653                         break;
 654                 if (rate_mask & (1 << low))
 655                         break;
 656                 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
 657         }
 658
 659         high = index;
 660         while (high != IWL_RATE_INVALID) {
 661                 high = iwl_rates[high].next_rs;
 662                 if (high == IWL_RATE_INVALID)
 663                         break;
 664                 if (rate_mask & (1 << high))
 665                         break;
 666                 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
 667         }
 668
 669         return (high << 8) | low;
 670 }
 671
 672 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 673                              struct iwl_scale_tbl_info *tbl,
 674                              u8 scale_index, u8 ht_possible)
 675 {
 676         s32 low;
 677         u16 rate_mask;
 678         u16 high_low;
 679         u8 switch_to_legacy = 0;
 680         u8 is_green = lq_sta->is_green;
 681         struct iwl_priv *priv = lq_sta->drv;
 682
 683         /* check if we need to switch from HT to legacy rates.
 684          * assumption is that mandatory rates (1Mbps or 6Mbps)
 685          * are always supported (spec demand) */
 686         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 687                 switch_to_legacy = 1;
 688                 scale_index = rs_ht_to_legacy[scale_index];
 689                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 690                         tbl->lq_type = LQ_A;
 691                 else
 692                         tbl->lq_type = LQ_G;
 693
 694                 if (num_of_ant(tbl->ant_type) > 1)
 695                         tbl->ant_type =
 696                                 first_antenna(priv->hw_params.valid_tx_ant);
 697
 698                 tbl->is_ht40 = 0;
 699                 tbl->is_SGI = 0;
 700                 tbl->max_search = IWL_MAX_SEARCH;
 701         }
 702
 703         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 704
 705         /* Mask with station rate restriction */
 706         if (is_legacy(tbl->lq_type)) {
 707                 /* supp_rates has no CCK bits in A mode */
 708                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 709                         rate_mask  = (u16)(rate_mask &
 710                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 711                 else
 712                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 713         }
 714
 715         /* If we switched from HT to legacy, check current rate */
 716         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 717                 low = scale_index;
 718                 goto out;
 719         }
 720
 721         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 722                                         tbl->lq_type);
 723         low = high_low & 0xff;
 724
 725         if (low == IWL_RATE_INVALID)
 726                 low = scale_index;
 727
 728 out:
 729         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 730 }
 731
 732 /*
 733  * Simple function to compare two rate scale table types
 734  */
 735 static bool table_type_matches(struct iwl_scale_tbl_info *a,
 736                                struct iwl_scale_tbl_info *b)
 737 {
 738         return (a->lq_type == b->lq_type) && (a->ant_type == b->ant_type) &&
 739                 (a->is_SGI == b->is_SGI);
 740 }
 741 /*
 742  * Static function to get the expected throughput from an iwl_scale_tbl_info
 743  * that wraps a NULL pointer check
 744  */
 745 static s32 get_expected_tpt(struct iwl_scale_tbl_info *tbl, int rs_index)
 746 {
 747         if (tbl->expected_tpt)
 748                 return tbl->expected_tpt[rs_index];
 749         return 0;
 750 }
 751
 752 /*
 753  * mac80211 sends us Tx status
 754  */
 755 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 756                          struct ieee80211_sta *sta, void *priv_sta,
 757                          struct sk_buff *skb)
 758 {
 759         int legacy_success;
 760         int retries;
 761         int rs_index, mac_index, i;
 762         struct iwl_lq_sta *lq_sta = priv_sta;
 763         struct iwl_link_quality_cmd *table;
 764         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 765         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 766         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 767         struct iwl_rate_scale_data *window = NULL;
 768         enum mac80211_rate_control_flags mac_flags;
 769         u32 tx_rate;
 770         struct iwl_scale_tbl_info tbl_type;
 771         struct iwl_scale_tbl_info *curr_tbl, *other_tbl;
 772         s32 tpt = 0;
 773
 774         IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 775
 776         if (!ieee80211_is_data(hdr->frame_control) ||
 777             info->flags & IEEE80211_TX_CTL_NO_ACK)
 778                 return;
 779
 780         /* This packet was aggregated but doesn't carry status info */
 781         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 782             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 783                 return;
 784
 785         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 786             !lq_sta->ibss_sta_added)
 787                 return;
 788
 789         /*
 790          * Ignore this Tx frame response if its initial rate doesn't match
 791          * that of latest Link Quality command.  There may be stragglers
 792          * from a previous Link Quality command, but we're no longer interested
 793          * in those; they're either from the "active" mode while we're trying
 794          * to check "search" mode, or a prior "search" mode after we've moved
 795          * to a new "search" mode (which might become the new "active" mode).
 796          */
 797         table = &lq_sta->lq;
 798         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 799         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 800         if (priv->band == IEEE80211_BAND_5GHZ)
 801                 rs_index -= IWL_FIRST_OFDM_RATE;
 802         mac_flags = info->status.rates[0].flags;
 803         mac_index = info->status.rates[0].idx;
 804         /* For HT packets, map MCS to PLCP */
 805         if (mac_flags & IEEE80211_TX_RC_MCS) {
 806                 mac_index &= RATE_MCS_CODE_MSK; /* Remove # of streams */
 807                 if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE))
 808                         mac_index++;
 809                 /*
 810                  * mac80211 HT index is always zero-indexed; we need to move
 811                  * HT OFDM rates after CCK rates in 2.4 GHz band
 812                  */
 813                 if (priv->band == IEEE80211_BAND_2GHZ)
 814                         mac_index += IWL_FIRST_OFDM_RATE;
 815         }
 816         /* Here we actually compare this rate to the latest LQ command */
 817         if ((mac_index < 0) ||
 818             (tbl_type.is_SGI != !!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) ||
 819             (tbl_type.is_ht40 != !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 820             (tbl_type.is_dup != !!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) ||
 821             (tbl_type.ant_type != info->antenna_sel_tx) ||
 822             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(mac_flags & IEEE80211_TX_RC_MCS)) ||
 823             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 824             (rs_index != mac_index)) {
 825                 IWL_DEBUG_RATE(priv, "initial rate %d does not match %d (0x%x)\n", mac_index, rs_index, tx_rate);
 826                 /*
 827                  * Since rates mis-match, the last LQ command may have failed.
 828                  * After IWL_MISSED_RATE_MAX mis-matches, resync the uCode with
 829                  * ... driver.
 830                  */
 831                 lq_sta->missed_rate_counter++;
 832                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 833                         lq_sta->missed_rate_counter = 0;
 834                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 835                 }
 836                 /* Regardless, ignore this status info for outdated rate */
 837                 return;
 838         } else
 839                 /* Rate did match, so reset the missed_rate_counter */
 840                 lq_sta->missed_rate_counter = 0;
 841
 842         /* Figure out if rate scale algorithm is in active or search table */
 843         if (table_type_matches(&tbl_type,
 844                                 &(lq_sta->lq_info[lq_sta->active_tbl]))) {
 845                 curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 846                 other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 847         } else if (table_type_matches(&tbl_type,
 848                                 &lq_sta->lq_info[1 - lq_sta->active_tbl])) {
 849                 curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 850                 other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 851         } else {
 852                 IWL_DEBUG_RATE(priv, "Neither active nor search matches tx rate\n");
 853                 return;
 854         }
 855         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 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                 tpt = get_expected_tpt(curr_tbl, rs_index);
 869                 rs_collect_tx_data(window, rs_index, tpt,
 870                                    info->status.ampdu_ack_len,
 871                                    info->status.ampdu_ack_map);
 872
 873                 /* Update success/fail counts if not searching for new mode */
 874                 if (lq_sta->stay_in_tbl) {
 875                         lq_sta->total_success += info->status.ampdu_ack_map;
 876                         lq_sta->total_failed += (info->status.ampdu_ack_len -
 877                                         info->status.ampdu_ack_map);
 878                 }
 879         } else {
 880         /*
 881          * For legacy, update frame history with for each Tx retry.
 882          */
 883                 retries = info->status.rates[0].count - 1;
 884                 /* HW doesn't send more than 15 retries */
 885                 retries = min(retries, 15);
 886
 887                 /* The last transmission may have been successful */
 888                 legacy_success = !!(info->flags & IEEE80211_TX_STAT_ACK);
 889                 /* Collect data for each rate used during failed TX attempts */
 890                 for (i = 0; i <= retries; ++i) {
 891                         tx_rate = le32_to_cpu(table->rs_table[i].rate_n_flags);
 892                         rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 893                                         &tbl_type, &rs_index);
 894                         /*
 895                          * Only collect stats if retried rate is in the same RS
 896                          * table as active/search.
 897                          */
 898                         if (table_type_matches(&tbl_type, curr_tbl))
 899                                 tpt = get_expected_tpt(curr_tbl, rs_index);
 900                         else if (table_type_matches(&tbl_type, other_tbl))
 901                                 tpt = get_expected_tpt(other_tbl, rs_index);
 902                         else
 903                                 continue;
 904
 905                         /* Constants mean 1 transmission, 0 successes */
 906                         if (i < retries)
 907                                 rs_collect_tx_data(window, rs_index, tpt, 1,
 908                                                 0);
 909                         else
 910                                 rs_collect_tx_data(window, rs_index, tpt, 1,
 911                                                 legacy_success);
 912                 }
 913
 914                 /* Update success/fail counts if not searching for new mode */
 915                 if (lq_sta->stay_in_tbl) {
 916                         lq_sta->total_success += legacy_success;
 917                         lq_sta->total_failed += retries + (1 - legacy_success);
 918                 }
 919         }
 920         /* The last TX rate is cached in lq_sta; it's set in if/else above */
 921         lq_sta->last_rate_n_flags = tx_rate;
 922
 923         /* See if there's a better rate or modulation mode to try. */
 924         if (sta && sta->supp_rates[sband->band])
 925                 rs_rate_scale_perform(priv, skb, sta, lq_sta);
 926 }
 927
 928 /*
 929  * Begin a period of staying with a selected modulation mode.
 930  * Set "stay_in_tbl" flag to prevent any mode switches.
 931  * Set frame tx success limits according to legacy vs. high-throughput,
 932  * and reset overall (spanning all rates) tx success history statistics.
 933  * These control how long we stay using same modulation mode before
 934  * searching for a new mode.
 935  */
 936 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
 937                                  struct iwl_lq_sta *lq_sta)
 938 {
 939         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
 940         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
 941         if (is_legacy) {
 942                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
 943                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
 944                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
 945         } else {
 946                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
 947                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
 948                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
 949         }
 950         lq_sta->table_count = 0;
 951         lq_sta->total_failed = 0;
 952         lq_sta->total_success = 0;
 953         lq_sta->flush_timer = jiffies;
 954         lq_sta->action_counter = 0;
 955 }
 956
 957 /*
 958  * Find correct throughput table for given mode of modulation
 959  */
 960 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
 961                                       struct iwl_scale_tbl_info *tbl)
 962 {
 963         /* Used to choose among HT tables */
 964         s32 (*ht_tbl_pointer)[IWL_RATE_COUNT];
 965
 966         /* Check for invalid LQ type */
 967         if (WARN_ON_ONCE(!is_legacy(tbl->lq_type) && !is_Ht(tbl->lq_type))) {
 968                 tbl->expected_tpt = expected_tpt_legacy;
 969                 return;
 970         }
 971
 972         /* Legacy rates have only one table */
 973         if (is_legacy(tbl->lq_type)) {
 974                 tbl->expected_tpt = expected_tpt_legacy;
 975                 return;
 976         }
 977
 978         /* Choose among many HT tables depending on number of streams
 979          * (SISO/MIMO2/MIMO3), channel width (20/40), SGI, and aggregation
 980          * status */
 981         if (is_siso(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 982                 ht_tbl_pointer = expected_tpt_siso20MHz;
 983         else if (is_siso(tbl->lq_type))
 984                 ht_tbl_pointer = expected_tpt_siso40MHz;
 985         else if (is_mimo2(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 986                 ht_tbl_pointer = expected_tpt_mimo2_20MHz;
 987         else if (is_mimo2(tbl->lq_type))
 988                 ht_tbl_pointer = expected_tpt_mimo2_40MHz;
 989         else if (is_mimo3(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 990                 ht_tbl_pointer = expected_tpt_mimo3_20MHz;
 991         else /* if (is_mimo3(tbl->lq_type)) <-- must be true */
 992                 ht_tbl_pointer = expected_tpt_mimo3_40MHz;
 993
 994         if (!tbl->is_SGI && !lq_sta->is_agg)            /* Normal */
 995                 tbl->expected_tpt = ht_tbl_pointer[0];
 996         else if (tbl->is_SGI && !lq_sta->is_agg)        /* SGI */
 997                 tbl->expected_tpt = ht_tbl_pointer[1];
 998         else if (!tbl->is_SGI && lq_sta->is_agg)        /* AGG */
 999                 tbl->expected_tpt = ht_tbl_pointer[2];
1000         else                                            /* AGG+SGI */
1001                 tbl->expected_tpt = ht_tbl_pointer[3];
1002 }
1003
1004 /*
1005  * Find starting rate for new "search" high-throughput mode of modulation.
1006  * Goal is to find lowest expected rate (under perfect conditions) that is
1007  * above the current measured throughput of "active" mode, to give new mode
1008  * a fair chance to prove itself without too many challenges.
1009  *
1010  * This gets called when transitioning to more aggressive modulation
1011  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1012  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1013  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1014  * bit rate will typically need to increase, but not if performance was bad.
1015  */
1016 static s32 rs_get_best_rate(struct iwl_priv *priv,
1017                             struct iwl_lq_sta *lq_sta,
1018                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1019                             u16 rate_mask, s8 index)
1020 {
1021         /* "active" values */
1022         struct iwl_scale_tbl_info *active_tbl =
1023             &(lq_sta->lq_info[lq_sta->active_tbl]);
1024         s32 active_sr = active_tbl->win[index].success_ratio;
1025         s32 active_tpt = active_tbl->expected_tpt[index];
1026
1027         /* expected "search" throughput */
1028         s32 *tpt_tbl = tbl->expected_tpt;
1029
1030         s32 new_rate, high, low, start_hi;
1031         u16 high_low;
1032         s8 rate = index;
1033
1034         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1035
1036         for (; ;) {
1037                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1038                                                 tbl->lq_type);
1039
1040                 low = high_low & 0xff;
1041                 high = (high_low >> 8) & 0xff;
1042
1043                 /*
1044                  * Lower the "search" bit rate, to give new "search" mode
1045                  * approximately the same throughput as "active" if:
1046                  *
1047                  * 1) "Active" mode has been working modestly well (but not
1048                  *    great), and expected "search" throughput (under perfect
1049                  *    conditions) at candidate rate is above the actual
1050                  *    measured "active" throughput (but less than expected
1051                  *    "active" throughput under perfect conditions).
1052                  * OR
1053                  * 2) "Active" mode has been working perfectly or very well
1054                  *    and expected "search" throughput (under perfect
1055                  *    conditions) at candidate rate is above expected
1056                  *    "active" throughput (under perfect conditions).
1057                  */
1058                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1059                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1060                       (active_sr <= IWL_RATE_HIGH_TH) &&
1061                       (tpt_tbl[rate] <= active_tpt))) ||
1062                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1063                      (tpt_tbl[rate] > active_tpt))) {
1064
1065                         /* (2nd or later pass)
1066                          * If we've already tried to raise the rate, and are
1067                          * now trying to lower it, use the higher rate. */
1068                         if (start_hi != IWL_RATE_INVALID) {
1069                                 new_rate = start_hi;
1070                                 break;
1071                         }
1072
1073                         new_rate = rate;
1074
1075                         /* Loop again with lower rate */
1076                         if (low != IWL_RATE_INVALID)
1077                                 rate = low;
1078
1079                         /* Lower rate not available, use the original */
1080                         else
1081                                 break;
1082
1083                 /* Else try to raise the "search" rate to match "active" */
1084                 } else {
1085                         /* (2nd or later pass)
1086                          * If we've already tried to lower the rate, and are
1087                          * now trying to raise it, use the lower rate. */
1088                         if (new_rate != IWL_RATE_INVALID)
1089                                 break;
1090
1091                         /* Loop again with higher rate */
1092                         else if (high != IWL_RATE_INVALID) {
1093                                 start_hi = high;
1094                                 rate = high;
1095
1096                         /* Higher rate not available, use the original */
1097                         } else {
1098                                 new_rate = rate;
1099                                 break;
1100                         }
1101                 }
1102         }
1103
1104         return new_rate;
1105 }
1106
1107 /*
1108  * Set up search table for MIMO2
1109  */
1110 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1111                              struct iwl_lq_sta *lq_sta,
1112                              struct ieee80211_conf *conf,
1113                              struct ieee80211_sta *sta,
1114                              struct iwl_scale_tbl_info *tbl, int index)
1115 {
1116         u16 rate_mask;
1117         s32 rate;
1118         s8 is_green = lq_sta->is_green;
1119
1120         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1121                 return -1;
1122
1123         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1124                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1125                 return -1;
1126
1127         /* Need both Tx chains/antennas to support MIMO */
1128         if (priv->hw_params.tx_chains_num < 2)
1129                 return -1;
1130
1131         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1132
1133         tbl->lq_type = LQ_MIMO2;
1134         tbl->is_dup = lq_sta->is_dup;
1135         tbl->action = 0;
1136         tbl->max_search = IWL_MAX_SEARCH;
1137         rate_mask = lq_sta->active_mimo2_rate;
1138
1139         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1140                 tbl->is_ht40 = 1;
1141         else
1142                 tbl->is_ht40 = 0;
1143
1144         rs_set_expected_tpt_table(lq_sta, tbl);
1145
1146         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1147
1148         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1149         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1150                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1151                                                 rate, rate_mask);
1152                 return -1;
1153         }
1154         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1155
1156         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1157                      tbl->current_rate, is_green);
1158         return 0;
1159 }
1160
1161 /*
1162  * Set up search table for MIMO3
1163  */
1164 static int rs_switch_to_mimo3(struct iwl_priv *priv,
1165                              struct iwl_lq_sta *lq_sta,
1166                              struct ieee80211_conf *conf,
1167                              struct ieee80211_sta *sta,
1168                              struct iwl_scale_tbl_info *tbl, int index)
1169 {
1170         u16 rate_mask;
1171         s32 rate;
1172         s8 is_green = lq_sta->is_green;
1173
1174         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1175                 return -1;
1176
1177         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1178                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1179                 return -1;
1180
1181         /* Need both Tx chains/antennas to support MIMO */
1182         if (priv->hw_params.tx_chains_num < 3)
1183                 return -1;
1184
1185         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO3\n");
1186
1187         tbl->lq_type = LQ_MIMO3;
1188         tbl->is_dup = lq_sta->is_dup;
1189         tbl->action = 0;
1190         tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
1191         rate_mask = lq_sta->active_mimo3_rate;
1192
1193         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1194                 tbl->is_ht40 = 1;
1195         else
1196                 tbl->is_ht40 = 0;
1197
1198         rs_set_expected_tpt_table(lq_sta, tbl);
1199
1200         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1201
1202         IWL_DEBUG_RATE(priv, "LQ: MIMO3 best rate %d mask %X\n",
1203                 rate, rate_mask);
1204         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1205                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1206                                                 rate, rate_mask);
1207                 return -1;
1208         }
1209         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1210
1211         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1212                      tbl->current_rate, is_green);
1213         return 0;
1214 }
1215
1216 /*
1217  * Set up search table for SISO
1218  */
1219 static int rs_switch_to_siso(struct iwl_priv *priv,
1220                              struct iwl_lq_sta *lq_sta,
1221                              struct ieee80211_conf *conf,
1222                              struct ieee80211_sta *sta,
1223                              struct iwl_scale_tbl_info *tbl, int index)
1224 {
1225         u16 rate_mask;
1226         u8 is_green = lq_sta->is_green;
1227         s32 rate;
1228
1229         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1230                 return -1;
1231
1232         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1233
1234         tbl->is_dup = lq_sta->is_dup;
1235         tbl->lq_type = LQ_SISO;
1236         tbl->action = 0;
1237         tbl->max_search = IWL_MAX_SEARCH;
1238         rate_mask = lq_sta->active_siso_rate;
1239
1240         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1241                 tbl->is_ht40 = 1;
1242         else
1243                 tbl->is_ht40 = 0;
1244
1245         if (is_green)
1246                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1247
1248         rs_set_expected_tpt_table(lq_sta, tbl);
1249         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1250
1251         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1252         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1253                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1254                              rate, rate_mask);
1255                 return -1;
1256         }
1257         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1258         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1259                      tbl->current_rate, is_green);
1260         return 0;
1261 }
1262
1263 /*
1264  * Try to switch to new modulation mode from legacy
1265  */
1266 static int rs_move_legacy_other(struct iwl_priv *priv,
1267                                 struct iwl_lq_sta *lq_sta,
1268                                 struct ieee80211_conf *conf,
1269                                 struct ieee80211_sta *sta,
1270                                 int index)
1271 {
1272         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1273         struct iwl_scale_tbl_info *search_tbl =
1274                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1275         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1276         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1277                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1278         u8 start_action = tbl->action;
1279         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1280         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1281         int ret = 0;
1282         u8 update_search_tbl_counter = 0;
1283
1284         if (!iwl_ht_enabled(priv))
1285                 /* stay in Legacy */
1286                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1287         else if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1288                    tbl->action > IWL_LEGACY_SWITCH_SISO)
1289                 tbl->action = IWL_LEGACY_SWITCH_SISO;
1290         for (; ;) {
1291                 lq_sta->action_counter++;
1292                 switch (tbl->action) {
1293                 case IWL_LEGACY_SWITCH_ANTENNA1:
1294                 case IWL_LEGACY_SWITCH_ANTENNA2:
1295                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1296
1297                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1298                                                         tx_chains_num <= 1) ||
1299                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1300                                                         tx_chains_num <= 2))
1301                                 break;
1302
1303                         /* Don't change antenna if success has been great */
1304                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1305                                 break;
1306
1307                         /* Set up search table to try other antenna */
1308                         memcpy(search_tbl, tbl, sz);
1309
1310                         if (rs_toggle_antenna(valid_tx_ant,
1311                                 &search_tbl->current_rate, search_tbl)) {
1312                                 update_search_tbl_counter = 1;
1313                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1314                                 goto out;
1315                         }
1316                         break;
1317                 case IWL_LEGACY_SWITCH_SISO:
1318                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1319
1320                         /* Set up search table to try SISO */
1321                         memcpy(search_tbl, tbl, sz);
1322                         search_tbl->is_SGI = 0;
1323                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1324                                                  search_tbl, index);
1325                         if (!ret) {
1326                                 lq_sta->action_counter = 0;
1327                                 goto out;
1328                         }
1329
1330                         break;
1331                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1332                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1333                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1334                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1335
1336                         /* Set up search table to try MIMO */
1337                         memcpy(search_tbl, tbl, sz);
1338                         search_tbl->is_SGI = 0;
1339
1340                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1341                                 search_tbl->ant_type = ANT_AB;
1342                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1343                                 search_tbl->ant_type = ANT_AC;
1344                         else
1345                                 search_tbl->ant_type = ANT_BC;
1346
1347                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1348                                 break;
1349
1350                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1351                                                  search_tbl, index);
1352                         if (!ret) {
1353                                 lq_sta->action_counter = 0;
1354                                 goto out;
1355                         }
1356                         break;
1357
1358                 case IWL_LEGACY_SWITCH_MIMO3_ABC:
1359                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO3\n");
1360
1361                         /* Set up search table to try MIMO3 */
1362                         memcpy(search_tbl, tbl, sz);
1363                         search_tbl->is_SGI = 0;
1364
1365                         search_tbl->ant_type = ANT_ABC;
1366
1367                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1368                                 break;
1369
1370                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1371                                                  search_tbl, index);
1372                         if (!ret) {
1373                                 lq_sta->action_counter = 0;
1374                                 goto out;
1375                         }
1376                         break;
1377                 }
1378                 tbl->action++;
1379                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1380                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1381
1382                 if (tbl->action == start_action)
1383                         break;
1384
1385         }
1386         search_tbl->lq_type = LQ_NONE;
1387         return 0;
1388
1389 out:
1390         lq_sta->search_better_tbl = 1;
1391         tbl->action++;
1392         if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1393                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1394         if (update_search_tbl_counter)
1395                 search_tbl->action = tbl->action;
1396         return 0;
1397
1398 }
1399
1400 /*
1401  * Try to switch to new modulation mode from SISO
1402  */
1403 static int rs_move_siso_to_other(struct iwl_priv *priv,
1404                                  struct iwl_lq_sta *lq_sta,
1405                                  struct ieee80211_conf *conf,
1406                                  struct ieee80211_sta *sta, int index)
1407 {
1408         u8 is_green = lq_sta->is_green;
1409         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1410         struct iwl_scale_tbl_info *search_tbl =
1411                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1412         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1413         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1414         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1415                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1416         u8 start_action = tbl->action;
1417         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1418         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1419         u8 update_search_tbl_counter = 0;
1420         int ret;
1421
1422         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1423             tbl->action > IWL_SISO_SWITCH_ANTENNA2) {
1424                 /* stay in SISO */
1425                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1426         }
1427         for (;;) {
1428                 lq_sta->action_counter++;
1429                 switch (tbl->action) {
1430                 case IWL_SISO_SWITCH_ANTENNA1:
1431                 case IWL_SISO_SWITCH_ANTENNA2:
1432                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1433
1434                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1435                                                         tx_chains_num <= 1) ||
1436                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1437                                                         tx_chains_num <= 2))
1438                                 break;
1439
1440                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1441                                 break;
1442
1443                         memcpy(search_tbl, tbl, sz);
1444                         if (rs_toggle_antenna(valid_tx_ant,
1445                                        &search_tbl->current_rate, search_tbl)) {
1446                                 update_search_tbl_counter = 1;
1447                                 goto out;
1448                         }
1449                         break;
1450                 case IWL_SISO_SWITCH_MIMO2_AB:
1451                 case IWL_SISO_SWITCH_MIMO2_AC:
1452                 case IWL_SISO_SWITCH_MIMO2_BC:
1453                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1454                         memcpy(search_tbl, tbl, sz);
1455                         search_tbl->is_SGI = 0;
1456
1457                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1458                                 search_tbl->ant_type = ANT_AB;
1459                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1460                                 search_tbl->ant_type = ANT_AC;
1461                         else
1462                                 search_tbl->ant_type = ANT_BC;
1463
1464                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1465                                 break;
1466
1467                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1468                                                  search_tbl, index);
1469                         if (!ret)
1470                                 goto out;
1471                         break;
1472                 case IWL_SISO_SWITCH_GI:
1473                         if (!tbl->is_ht40 && !(ht_cap->cap &
1474                                                 IEEE80211_HT_CAP_SGI_20))
1475                                 break;
1476                         if (tbl->is_ht40 && !(ht_cap->cap &
1477                                                 IEEE80211_HT_CAP_SGI_40))
1478                                 break;
1479
1480                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1481
1482                         memcpy(search_tbl, tbl, sz);
1483                         if (is_green) {
1484                                 if (!tbl->is_SGI)
1485                                         break;
1486                                 else
1487                                         IWL_ERR(priv,
1488                                                 "SGI was set in GF+SISO\n");
1489                         }
1490                         search_tbl->is_SGI = !tbl->is_SGI;
1491                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1492                         if (tbl->is_SGI) {
1493                                 s32 tpt = lq_sta->last_tpt / 100;
1494                                 if (tpt >= search_tbl->expected_tpt[index])
1495                                         break;
1496                         }
1497                         search_tbl->current_rate =
1498                                 rate_n_flags_from_tbl(priv, search_tbl,
1499                                                       index, is_green);
1500                         update_search_tbl_counter = 1;
1501                         goto out;
1502                 case IWL_SISO_SWITCH_MIMO3_ABC:
1503                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO3\n");
1504                         memcpy(search_tbl, tbl, sz);
1505                         search_tbl->is_SGI = 0;
1506                         search_tbl->ant_type = ANT_ABC;
1507
1508                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1509                                 break;
1510
1511                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1512                                                  search_tbl, index);
1513                         if (!ret)
1514                                 goto out;
1515                         break;
1516                 }
1517                 tbl->action++;
1518                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1519                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1520
1521                 if (tbl->action == start_action)
1522                         break;
1523         }
1524         search_tbl->lq_type = LQ_NONE;
1525         return 0;
1526
1527  out:
1528         lq_sta->search_better_tbl = 1;
1529         tbl->action++;
1530         if (tbl->action > IWL_SISO_SWITCH_MIMO3_ABC)
1531                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1532         if (update_search_tbl_counter)
1533                 search_tbl->action = tbl->action;
1534
1535         return 0;
1536 }
1537
1538 /*
1539  * Try to switch to new modulation mode from MIMO2
1540  */
1541 static int rs_move_mimo2_to_other(struct iwl_priv *priv,
1542                                  struct iwl_lq_sta *lq_sta,
1543                                  struct ieee80211_conf *conf,
1544                                  struct ieee80211_sta *sta, int index)
1545 {
1546         s8 is_green = lq_sta->is_green;
1547         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1548         struct iwl_scale_tbl_info *search_tbl =
1549                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1550         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1551         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1552         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1553                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1554         u8 start_action = tbl->action;
1555         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1556         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1557         u8 update_search_tbl_counter = 0;
1558         int ret;
1559
1560         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1561             (tbl->action < IWL_MIMO2_SWITCH_SISO_A ||
1562              tbl->action > IWL_MIMO2_SWITCH_SISO_C)) {
1563                 /* switch in SISO */
1564                 tbl->action = IWL_MIMO2_SWITCH_SISO_A;
1565         }
1566         for (;;) {
1567                 lq_sta->action_counter++;
1568                 switch (tbl->action) {
1569                 case IWL_MIMO2_SWITCH_ANTENNA1:
1570                 case IWL_MIMO2_SWITCH_ANTENNA2:
1571                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1572
1573                         if (tx_chains_num <= 2)
1574                                 break;
1575
1576                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1577                                 break;
1578
1579                         memcpy(search_tbl, tbl, sz);
1580                         if (rs_toggle_antenna(valid_tx_ant,
1581                                        &search_tbl->current_rate, search_tbl)) {
1582                                 update_search_tbl_counter = 1;
1583                                 goto out;
1584                         }
1585                         break;
1586                 case IWL_MIMO2_SWITCH_SISO_A:
1587                 case IWL_MIMO2_SWITCH_SISO_B:
1588                 case IWL_MIMO2_SWITCH_SISO_C:
1589                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1590
1591                         /* Set up new search table for SISO */
1592                         memcpy(search_tbl, tbl, sz);
1593
1594                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1595                                 search_tbl->ant_type = ANT_A;
1596                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1597                                 search_tbl->ant_type = ANT_B;
1598                         else
1599                                 search_tbl->ant_type = ANT_C;
1600
1601                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1602                                 break;
1603
1604                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1605                                                  search_tbl, index);
1606                         if (!ret)
1607                                 goto out;
1608
1609                         break;
1610
1611                 case IWL_MIMO2_SWITCH_GI:
1612                         if (!tbl->is_ht40 && !(ht_cap->cap &
1613                                                 IEEE80211_HT_CAP_SGI_20))
1614                                 break;
1615                         if (tbl->is_ht40 && !(ht_cap->cap &
1616                                                 IEEE80211_HT_CAP_SGI_40))
1617                                 break;
1618
1619                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1620
1621                         /* Set up new search table for MIMO2 */
1622                         memcpy(search_tbl, tbl, sz);
1623                         search_tbl->is_SGI = !tbl->is_SGI;
1624                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1625                         /*
1626                          * If active table already uses the fastest possible
1627                          * modulation (dual stream with short guard interval),
1628                          * and it's working well, there's no need to look
1629                          * for a better type of modulation!
1630                          */
1631                         if (tbl->is_SGI) {
1632                                 s32 tpt = lq_sta->last_tpt / 100;
1633                                 if (tpt >= search_tbl->expected_tpt[index])
1634                                         break;
1635                         }
1636                         search_tbl->current_rate =
1637                                 rate_n_flags_from_tbl(priv, search_tbl,
1638                                                       index, is_green);
1639                         update_search_tbl_counter = 1;
1640                         goto out;
1641
1642                 case IWL_MIMO2_SWITCH_MIMO3_ABC:
1643                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to MIMO3\n");
1644                         memcpy(search_tbl, tbl, sz);
1645                         search_tbl->is_SGI = 0;
1646                         search_tbl->ant_type = ANT_ABC;
1647
1648                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1649                                 break;
1650
1651                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1652                                                  search_tbl, index);
1653                         if (!ret)
1654                                 goto out;
1655
1656                         break;
1657                 }
1658                 tbl->action++;
1659                 if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1660                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1661
1662                 if (tbl->action == start_action)
1663                         break;
1664         }
1665         search_tbl->lq_type = LQ_NONE;
1666         return 0;
1667  out:
1668         lq_sta->search_better_tbl = 1;
1669         tbl->action++;
1670         if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1671                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1672         if (update_search_tbl_counter)
1673                 search_tbl->action = tbl->action;
1674
1675         return 0;
1676
1677 }
1678
1679 /*
1680  * Try to switch to new modulation mode from MIMO3
1681  */
1682 static int rs_move_mimo3_to_other(struct iwl_priv *priv,
1683                                  struct iwl_lq_sta *lq_sta,
1684                                  struct ieee80211_conf *conf,
1685                                  struct ieee80211_sta *sta, int index)
1686 {
1687         s8 is_green = lq_sta->is_green;
1688         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1689         struct iwl_scale_tbl_info *search_tbl =
1690                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1691         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1692         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1693         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1694                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1695         u8 start_action = tbl->action;
1696         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1697         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1698         int ret;
1699         u8 update_search_tbl_counter = 0;
1700
1701         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1702             (tbl->action < IWL_MIMO3_SWITCH_SISO_A ||
1703              tbl->action > IWL_MIMO3_SWITCH_SISO_C)) {
1704                 /* switch in SISO */
1705                 tbl->action = IWL_MIMO3_SWITCH_SISO_A;
1706         }
1707         for (;;) {
1708                 lq_sta->action_counter++;
1709                 switch (tbl->action) {
1710                 case IWL_MIMO3_SWITCH_ANTENNA1:
1711                 case IWL_MIMO3_SWITCH_ANTENNA2:
1712                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle Antennas\n");
1713
1714                         if (tx_chains_num <= 3)
1715                                 break;
1716
1717                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1718                                 break;
1719
1720                         memcpy(search_tbl, tbl, sz);
1721                         if (rs_toggle_antenna(valid_tx_ant,
1722                                        &search_tbl->current_rate, search_tbl))
1723                                 goto out;
1724                         break;
1725                 case IWL_MIMO3_SWITCH_SISO_A:
1726                 case IWL_MIMO3_SWITCH_SISO_B:
1727                 case IWL_MIMO3_SWITCH_SISO_C:
1728                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to SISO\n");
1729
1730                         /* Set up new search table for SISO */
1731                         memcpy(search_tbl, tbl, sz);
1732
1733                         if (tbl->action == IWL_MIMO3_SWITCH_SISO_A)
1734                                 search_tbl->ant_type = ANT_A;
1735                         else if (tbl->action == IWL_MIMO3_SWITCH_SISO_B)
1736                                 search_tbl->ant_type = ANT_B;
1737                         else
1738                                 search_tbl->ant_type = ANT_C;
1739
1740                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1741                                 break;
1742
1743                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1744                                                  search_tbl, index);
1745                         if (!ret)
1746                                 goto out;
1747
1748                         break;
1749
1750                 case IWL_MIMO3_SWITCH_MIMO2_AB:
1751                 case IWL_MIMO3_SWITCH_MIMO2_AC:
1752                 case IWL_MIMO3_SWITCH_MIMO2_BC:
1753                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to MIMO2\n");
1754
1755                         memcpy(search_tbl, tbl, sz);
1756                         search_tbl->is_SGI = 0;
1757                         if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AB)
1758                                 search_tbl->ant_type = ANT_AB;
1759                         else if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AC)
1760                                 search_tbl->ant_type = ANT_AC;
1761                         else
1762                                 search_tbl->ant_type = ANT_BC;
1763
1764                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1765                                 break;
1766
1767                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1768                                                  search_tbl, index);
1769                         if (!ret)
1770                                 goto out;
1771
1772                         break;
1773
1774                 case IWL_MIMO3_SWITCH_GI:
1775                         if (!tbl->is_ht40 && !(ht_cap->cap &
1776                                                 IEEE80211_HT_CAP_SGI_20))
1777                                 break;
1778                         if (tbl->is_ht40 && !(ht_cap->cap &
1779                                                 IEEE80211_HT_CAP_SGI_40))
1780                                 break;
1781
1782                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle SGI/NGI\n");
1783
1784                         /* Set up new search table for MIMO */
1785                         memcpy(search_tbl, tbl, sz);
1786                         search_tbl->is_SGI = !tbl->is_SGI;
1787                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1788                         /*
1789                          * If active table already uses the fastest possible
1790                          * modulation (dual stream with short guard interval),
1791                          * and it's working well, there's no need to look
1792                          * for a better type of modulation!
1793                          */
1794                         if (tbl->is_SGI) {
1795                                 s32 tpt = lq_sta->last_tpt / 100;
1796                                 if (tpt >= search_tbl->expected_tpt[index])
1797                                         break;
1798                         }
1799                         search_tbl->current_rate =
1800                                 rate_n_flags_from_tbl(priv, search_tbl,
1801                                                       index, is_green);
1802                         update_search_tbl_counter = 1;
1803                         goto out;
1804                 }
1805                 tbl->action++;
1806                 if (tbl->action > IWL_MIMO3_SWITCH_GI)
1807                         tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1808
1809                 if (tbl->action == start_action)
1810                         break;
1811         }
1812         search_tbl->lq_type = LQ_NONE;
1813         return 0;
1814  out:
1815         lq_sta->search_better_tbl = 1;
1816         tbl->action++;
1817         if (tbl->action > IWL_MIMO3_SWITCH_GI)
1818                 tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1819         if (update_search_tbl_counter)
1820                 search_tbl->action = tbl->action;
1821
1822         return 0;
1823
1824 }
1825
1826 /*
1827  * Check whether we should continue using same modulation mode, or
1828  * begin search for a new mode, based on:
1829  * 1) # tx successes or failures while using this mode
1830  * 2) # times calling this function
1831  * 3) elapsed time in this mode (not used, for now)
1832  */
1833 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1834 {
1835         struct iwl_scale_tbl_info *tbl;
1836         int i;
1837         int active_tbl;
1838         int flush_interval_passed = 0;
1839         struct iwl_priv *priv;
1840
1841         priv = lq_sta->drv;
1842         active_tbl = lq_sta->active_tbl;
1843
1844         tbl = &(lq_sta->lq_info[active_tbl]);
1845
1846         /* If we've been disallowing search, see if we should now allow it */
1847         if (lq_sta->stay_in_tbl) {
1848
1849                 /* Elapsed time using current modulation mode */
1850                 if (lq_sta->flush_timer)
1851                         flush_interval_passed =
1852                         time_after(jiffies,
1853                                         (unsigned long)(lq_sta->flush_timer +
1854                                         IWL_RATE_SCALE_FLUSH_INTVL));
1855
1856                 /*
1857                  * Check if we should allow search for new modulation mode.
1858                  * If many frames have failed or succeeded, or we've used
1859                  * this same modulation for a long time, allow search, and
1860                  * reset history stats that keep track of whether we should
1861                  * allow a new search.  Also (below) reset all bitmaps and
1862                  * stats in active history.
1863                  */
1864                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1865                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1866                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1867                      && (flush_interval_passed))) {
1868                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1869                                      lq_sta->total_failed,
1870                                      lq_sta->total_success,
1871                                      flush_interval_passed);
1872
1873                         /* Allow search for new mode */
1874                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1875                         lq_sta->total_failed = 0;
1876                         lq_sta->total_success = 0;
1877                         lq_sta->flush_timer = 0;
1878
1879                 /*
1880                  * Else if we've used this modulation mode enough repetitions
1881                  * (regardless of elapsed time or success/failure), reset
1882                  * history bitmaps and rate-specific stats for all rates in
1883                  * active table.
1884                  */
1885                 } else {
1886                         lq_sta->table_count++;
1887                         if (lq_sta->table_count >=
1888                             lq_sta->table_count_limit) {
1889                                 lq_sta->table_count = 0;
1890
1891                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
1892                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1893                                         rs_rate_scale_clear_window(
1894                                                 &(tbl->win[i]));
1895                         }
1896                 }
1897
1898                 /* If transitioning to allow "search", reset all history
1899                  * bitmaps and stats in active table (this will become the new
1900                  * "search" table). */
1901                 if (!lq_sta->stay_in_tbl) {
1902                         for (i = 0; i < IWL_RATE_COUNT; i++)
1903                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1904                 }
1905         }
1906 }
1907
1908 /*
1909  * setup rate table in uCode
1910  * return rate_n_flags as used in the table
1911  */
1912 static u32 rs_update_rate_tbl(struct iwl_priv *priv,
1913                                 struct iwl_lq_sta *lq_sta,
1914                                 struct iwl_scale_tbl_info *tbl,
1915                                 int index, u8 is_green)
1916 {
1917         u32 rate;
1918
1919         /* Update uCode's rate table. */
1920         rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
1921         rs_fill_link_cmd(priv, lq_sta, rate);
1922         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1923
1924         return rate;
1925 }
1926
1927 /*
1928  * Do rate scaling and search for new modulation mode.
1929  */
1930 static void rs_rate_scale_perform(struct iwl_priv *priv,
1931                                   struct sk_buff *skb,
1932                                   struct ieee80211_sta *sta,
1933                                   struct iwl_lq_sta *lq_sta)
1934 {
1935         struct ieee80211_hw *hw = priv->hw;
1936         struct ieee80211_conf *conf = &hw->conf;
1937         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1938         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1939         int low = IWL_RATE_INVALID;
1940         int high = IWL_RATE_INVALID;
1941         int index;
1942         int i;
1943         struct iwl_rate_scale_data *window = NULL;
1944         int current_tpt = IWL_INVALID_VALUE;
1945         int low_tpt = IWL_INVALID_VALUE;
1946         int high_tpt = IWL_INVALID_VALUE;
1947         u32 fail_count;
1948         s8 scale_action = 0;
1949         u16 rate_mask;
1950         u8 update_lq = 0;
1951         struct iwl_scale_tbl_info *tbl, *tbl1;
1952         u16 rate_scale_index_msk = 0;
1953         u32 rate;
1954         u8 is_green = 0;
1955         u8 active_tbl = 0;
1956         u8 done_search = 0;
1957         u16 high_low;
1958         s32 sr;
1959         u8 tid = MAX_TID_COUNT;
1960         struct iwl_tid_data *tid_data;
1961
1962         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
1963
1964         /* Send management frames and NO_ACK data using lowest rate. */
1965         /* TODO: this could probably be improved.. */
1966         if (!ieee80211_is_data(hdr->frame_control) ||
1967             info->flags & IEEE80211_TX_CTL_NO_ACK)
1968                 return;
1969
1970         if (!sta || !lq_sta)
1971                 return;
1972
1973         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1974
1975         tid = rs_tl_add_packet(lq_sta, hdr);
1976         if ((tid != MAX_TID_COUNT) && (lq_sta->tx_agg_tid_en & (1 << tid))) {
1977                 tid_data = &priv->stations[lq_sta->lq.sta_id].tid[tid];
1978                 if (tid_data->agg.state == IWL_AGG_OFF)
1979                         lq_sta->is_agg = 0;
1980                 else
1981                         lq_sta->is_agg = 1;
1982         } else
1983                 lq_sta->is_agg = 0;
1984
1985         /*
1986          * Select rate-scale / modulation-mode table to work with in
1987          * the rest of this function:  "search" if searching for better
1988          * modulation mode, or "active" if doing rate scaling within a mode.
1989          */
1990         if (!lq_sta->search_better_tbl)
1991                 active_tbl = lq_sta->active_tbl;
1992         else
1993                 active_tbl = 1 - lq_sta->active_tbl;
1994
1995         tbl = &(lq_sta->lq_info[active_tbl]);
1996         if (is_legacy(tbl->lq_type))
1997                 lq_sta->is_green = 0;
1998         else
1999                 lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2000         is_green = lq_sta->is_green;
2001
2002         /* current tx rate */
2003         index = lq_sta->last_txrate_idx;
2004
2005         IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
2006                        tbl->lq_type);
2007
2008         /* rates available for this association, and for modulation mode */
2009         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
2010
2011         IWL_DEBUG_RATE(priv, "mask 0x%04X \n", rate_mask);
2012
2013         /* mask with station rate restriction */
2014         if (is_legacy(tbl->lq_type)) {
2015                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
2016                         /* supp_rates has no CCK bits in A mode */
2017                         rate_scale_index_msk = (u16) (rate_mask &
2018                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
2019                 else
2020                         rate_scale_index_msk = (u16) (rate_mask &
2021                                                       lq_sta->supp_rates);
2022
2023         } else
2024                 rate_scale_index_msk = rate_mask;
2025
2026         if (!rate_scale_index_msk)
2027                 rate_scale_index_msk = rate_mask;
2028
2029         if (!((1 << index) & rate_scale_index_msk)) {
2030                 IWL_ERR(priv, "Current Rate is not valid\n");
2031                 if (lq_sta->search_better_tbl) {
2032                         /* revert to active table if search table is not valid*/
2033                         tbl->lq_type = LQ_NONE;
2034                         lq_sta->search_better_tbl = 0;
2035                         tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2036                         /* get "active" rate info */
2037                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2038                         rate = rs_update_rate_tbl(priv, lq_sta,
2039                                                   tbl, index, is_green);
2040                 }
2041                 return;
2042         }
2043
2044         /* Get expected throughput table and history window for current rate */
2045         if (!tbl->expected_tpt) {
2046                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
2047                 return;
2048         }
2049
2050         /* force user max rate if set by user */
2051         if ((lq_sta->max_rate_idx != -1) &&
2052             (lq_sta->max_rate_idx < index)) {
2053                 index = lq_sta->max_rate_idx;
2054                 update_lq = 1;
2055                 window = &(tbl->win[index]);
2056                 goto lq_update;
2057         }
2058
2059         window = &(tbl->win[index]);
2060
2061         /*
2062          * If there is not enough history to calculate actual average
2063          * throughput, keep analyzing results of more tx frames, without
2064          * changing rate or mode (bypass most of the rest of this function).
2065          * Set up new rate table in uCode only if old rate is not supported
2066          * in current association (use new rate found above).
2067          */
2068         fail_count = window->counter - window->success_counter;
2069         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
2070                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
2071                 IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
2072                                "for index %d\n",
2073                                window->success_counter, window->counter, index);
2074
2075                 /* Can't calculate this yet; not enough history */
2076                 window->average_tpt = IWL_INVALID_VALUE;
2077
2078                 /* Should we stay with this modulation mode,
2079                  * or search for a new one? */
2080                 rs_stay_in_table(lq_sta);
2081
2082                 goto out;
2083         }
2084         /* Else we have enough samples; calculate estimate of
2085          * actual average throughput */
2086
2087         /* Sanity-check TPT calculations */
2088         BUG_ON(window->average_tpt != ((window->success_ratio *
2089                         tbl->expected_tpt[index] + 64) / 128));
2090
2091         /* If we are searching for better modulation mode, check success. */
2092         if (lq_sta->search_better_tbl &&
2093             (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI)) {
2094                 /* If good success, continue using the "search" mode;
2095                  * no need to send new link quality command, since we're
2096                  * continuing to use the setup that we've been trying. */
2097                 if (window->average_tpt > lq_sta->last_tpt) {
2098
2099                         IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
2100                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2101                                         window->success_ratio,
2102                                         window->average_tpt,
2103                                         lq_sta->last_tpt);
2104
2105                         if (!is_legacy(tbl->lq_type))
2106                                 lq_sta->enable_counter = 1;
2107
2108                         /* Swap tables; "search" becomes "active" */
2109                         lq_sta->active_tbl = active_tbl;
2110                         current_tpt = window->average_tpt;
2111
2112                 /* Else poor success; go back to mode in "active" table */
2113                 } else {
2114
2115                         IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
2116                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2117                                         window->success_ratio,
2118                                         window->average_tpt,
2119                                         lq_sta->last_tpt);
2120
2121                         /* Nullify "search" table */
2122                         tbl->lq_type = LQ_NONE;
2123
2124                         /* Revert to "active" table */
2125                         active_tbl = lq_sta->active_tbl;
2126                         tbl = &(lq_sta->lq_info[active_tbl]);
2127
2128                         /* Revert to "active" rate and throughput info */
2129                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2130                         current_tpt = lq_sta->last_tpt;
2131
2132                         /* Need to set up a new rate table in uCode */
2133                         update_lq = 1;
2134                 }
2135
2136                 /* Either way, we've made a decision; modulation mode
2137                  * search is done, allow rate adjustment next time. */
2138                 lq_sta->search_better_tbl = 0;
2139                 done_search = 1;        /* Don't switch modes below! */
2140                 goto lq_update;
2141         }
2142
2143         /* (Else) not in search of better modulation mode, try for better
2144          * starting rate, while staying in this mode. */
2145         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
2146                                         tbl->lq_type);
2147         low = high_low & 0xff;
2148         high = (high_low >> 8) & 0xff;
2149
2150         /* If user set max rate, dont allow higher than user constrain */
2151         if ((lq_sta->max_rate_idx != -1) &&
2152             (lq_sta->max_rate_idx < high))
2153                 high = IWL_RATE_INVALID;
2154
2155         sr = window->success_ratio;
2156
2157         /* Collect measured throughputs for current and adjacent rates */
2158         current_tpt = window->average_tpt;
2159         if (low != IWL_RATE_INVALID)
2160                 low_tpt = tbl->win[low].average_tpt;
2161         if (high != IWL_RATE_INVALID)
2162                 high_tpt = tbl->win[high].average_tpt;
2163
2164         scale_action = 0;
2165
2166         /* Too many failures, decrease rate */
2167         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
2168                 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
2169                 scale_action = -1;
2170
2171         /* No throughput measured yet for adjacent rates; try increase. */
2172         } else if ((low_tpt == IWL_INVALID_VALUE) &&
2173                    (high_tpt == IWL_INVALID_VALUE)) {
2174
2175                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
2176                         scale_action = 1;
2177                 else if (low != IWL_RATE_INVALID)
2178                         scale_action = 0;
2179         }
2180
2181         /* Both adjacent throughputs are measured, but neither one has better
2182          * throughput; we're using the best rate, don't change it! */
2183         else if ((low_tpt != IWL_INVALID_VALUE) &&
2184                  (high_tpt != IWL_INVALID_VALUE) &&
2185                  (low_tpt < current_tpt) &&
2186                  (high_tpt < current_tpt))
2187                 scale_action = 0;
2188
2189         /* At least one adjacent rate's throughput is measured,
2190          * and may have better performance. */
2191         else {
2192                 /* Higher adjacent rate's throughput is measured */
2193                 if (high_tpt != IWL_INVALID_VALUE) {
2194                         /* Higher rate has better throughput */
2195                         if (high_tpt > current_tpt &&
2196                                         sr >= IWL_RATE_INCREASE_TH) {
2197                                 scale_action = 1;
2198                         } else {
2199                                 scale_action = 0;
2200                         }
2201
2202                 /* Lower adjacent rate's throughput is measured */
2203                 } else if (low_tpt != IWL_INVALID_VALUE) {
2204                         /* Lower rate has better throughput */
2205                         if (low_tpt > current_tpt) {
2206                                 IWL_DEBUG_RATE(priv,
2207                                     "decrease rate because of low tpt\n");
2208                                 scale_action = -1;
2209                         } else if (sr >= IWL_RATE_INCREASE_TH) {
2210                                 scale_action = 1;
2211                         }
2212                 }
2213         }
2214
2215         /* Sanity check; asked for decrease, but success rate or throughput
2216          * has been good at old rate.  Don't change it. */
2217         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
2218                     ((sr > IWL_RATE_HIGH_TH) ||
2219                      (current_tpt > (100 * tbl->expected_tpt[low]))))
2220                 scale_action = 0;
2221         if (!iwl_ht_enabled(priv) && !is_legacy(tbl->lq_type))
2222                 scale_action = -1;
2223         if (iwl_tx_ant_restriction(priv) != IWL_ANT_OK_MULTI &&
2224                 (is_mimo2(tbl->lq_type) || is_mimo3(tbl->lq_type)))
2225                 scale_action = -1;
2226         switch (scale_action) {
2227         case -1:
2228                 /* Decrease starting rate, update uCode's rate table */
2229                 if (low != IWL_RATE_INVALID) {
2230                         update_lq = 1;
2231                         index = low;
2232                 }
2233
2234                 break;
2235         case 1:
2236                 /* Increase starting rate, update uCode's rate table */
2237                 if (high != IWL_RATE_INVALID) {
2238                         update_lq = 1;
2239                         index = high;
2240                 }
2241
2242                 break;
2243         case 0:
2244                 /* No change */
2245         default:
2246                 break;
2247         }
2248
2249         IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
2250                     "high %d type %d\n",
2251                      index, scale_action, low, high, tbl->lq_type);
2252
2253 lq_update:
2254         /* Replace uCode's rate table for the destination station. */
2255         if (update_lq)
2256                 rate = rs_update_rate_tbl(priv, lq_sta,
2257                                           tbl, index, is_green);
2258
2259         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI) {
2260                 /* Should we stay with this modulation mode,
2261                  * or search for a new one? */
2262                 rs_stay_in_table(lq_sta);
2263         }
2264         /*
2265          * Search for new modulation mode if we're:
2266          * 1)  Not changing rates right now
2267          * 2)  Not just finishing up a search
2268          * 3)  Allowing a new search
2269          */
2270         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
2271                 /* Save current throughput to compare with "search" throughput*/
2272                 lq_sta->last_tpt = current_tpt;
2273
2274                 /* Select a new "search" modulation mode to try.
2275                  * If one is found, set up the new "search" table. */
2276                 if (is_legacy(tbl->lq_type))
2277                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
2278                 else if (is_siso(tbl->lq_type))
2279                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2280                 else if (is_mimo2(tbl->lq_type))
2281                         rs_move_mimo2_to_other(priv, lq_sta, conf, sta, index);
2282                 else
2283                         rs_move_mimo3_to_other(priv, lq_sta, conf, sta, index);
2284
2285                 /* If new "search" mode was selected, set up in uCode table */
2286                 if (lq_sta->search_better_tbl) {
2287                         /* Access the "search" table, clear its history. */
2288                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2289                         for (i = 0; i < IWL_RATE_COUNT; i++)
2290                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2291
2292                         /* Use new "search" start rate */
2293                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2294
2295                         IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
2296                                      tbl->current_rate, index);
2297                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
2298                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2299                 } else
2300                         done_search = 1;
2301         }
2302
2303         if (done_search && !lq_sta->stay_in_tbl) {
2304                 /* If the "active" (non-search) mode was legacy,
2305                  * and we've tried switching antennas,
2306                  * but we haven't been able to try HT modes (not available),
2307                  * stay with best antenna legacy modulation for a while
2308                  * before next round of mode comparisons. */
2309                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2310                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2311                     lq_sta->action_counter > tbl1->max_search) {
2312                         IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2313                         rs_set_stay_in_table(priv, 1, lq_sta);
2314                 }
2315
2316                 /* If we're in an HT mode, and all 3 mode switch actions
2317                  * have been tried and compared, stay in this best modulation
2318                  * mode for a while before next round of mode comparisons. */
2319                 if (lq_sta->enable_counter &&
2320                     (lq_sta->action_counter >= tbl1->max_search) &&
2321                     iwl_ht_enabled(priv)) {
2322                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2323                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2324                             (tid != MAX_TID_COUNT)) {
2325                                 tid_data =
2326                                    &priv->stations[lq_sta->lq.sta_id].tid[tid];
2327                                 if (tid_data->agg.state == IWL_AGG_OFF) {
2328                                         IWL_DEBUG_RATE(priv,
2329                                                        "try to aggregate tid %d\n",
2330                                                        tid);
2331                                         rs_tl_turn_on_agg(priv, tid,
2332                                                           lq_sta, sta);
2333                                 }
2334                         }
2335                         rs_set_stay_in_table(priv, 0, lq_sta);
2336                 }
2337         }
2338
2339 out:
2340         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2341         i = index;
2342         lq_sta->last_txrate_idx = i;
2343
2344         return;
2345 }
2346
2347
2348 static void rs_initialize_lq(struct iwl_priv *priv,
2349                              struct ieee80211_conf *conf,
2350                              struct ieee80211_sta *sta,
2351                              struct iwl_lq_sta *lq_sta)
2352 {
2353         struct iwl_scale_tbl_info *tbl;
2354         int rate_idx;
2355         int i;
2356         u32 rate;
2357         u8 use_green = rs_use_green(sta, &priv->current_ht_config);
2358         u8 active_tbl = 0;
2359         u8 valid_tx_ant;
2360
2361         if (!sta || !lq_sta)
2362                 goto out;
2363
2364         i = lq_sta->last_txrate_idx;
2365
2366         if ((lq_sta->lq.sta_id == 0xff) &&
2367             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2368                 goto out;
2369
2370         valid_tx_ant = priv->hw_params.valid_tx_ant;
2371
2372         if (!lq_sta->search_better_tbl)
2373                 active_tbl = lq_sta->active_tbl;
2374         else
2375                 active_tbl = 1 - lq_sta->active_tbl;
2376
2377         tbl = &(lq_sta->lq_info[active_tbl]);
2378
2379         if ((i < 0) || (i >= IWL_RATE_COUNT))
2380                 i = 0;
2381
2382         rate = iwl_rates[i].plcp;
2383         tbl->ant_type = first_antenna(valid_tx_ant);
2384         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2385
2386         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2387                 rate |= RATE_MCS_CCK_MSK;
2388
2389         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2390         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2391             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2392
2393         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2394         tbl->current_rate = rate;
2395         rs_set_expected_tpt_table(lq_sta, tbl);
2396         rs_fill_link_cmd(NULL, lq_sta, rate);
2397         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2398  out:
2399         return;
2400 }
2401
2402 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2403                         struct ieee80211_tx_rate_control *txrc)
2404 {
2405
2406         struct sk_buff *skb = txrc->skb;
2407         struct ieee80211_supported_band *sband = txrc->sband;
2408         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2409         struct ieee80211_conf *conf = &priv->hw->conf;
2410         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2411         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2412         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2413         struct iwl_lq_sta *lq_sta = priv_sta;
2414         int rate_idx;
2415
2416         IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2417
2418         /* Get max rate if user set max rate */
2419         if (lq_sta) {
2420                 lq_sta->max_rate_idx = txrc->max_rate_idx;
2421                 if ((sband->band == IEEE80211_BAND_5GHZ) &&
2422                     (lq_sta->max_rate_idx != -1))
2423                         lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2424                 if ((lq_sta->max_rate_idx < 0) ||
2425                     (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2426                         lq_sta->max_rate_idx = -1;
2427         }
2428
2429         /* Send management frames and NO_ACK data using lowest rate. */
2430         if (rate_control_send_low(sta, priv_sta, txrc))
2431                 return;
2432
2433         rate_idx  = lq_sta->last_txrate_idx;
2434
2435         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2436             !lq_sta->ibss_sta_added) {
2437                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2438
2439                 if (sta_id == IWL_INVALID_STATION) {
2440                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
2441                                        hdr->addr1);
2442                         sta_id = iwl_add_station(priv, hdr->addr1,
2443                                                 false, CMD_ASYNC, ht_cap);
2444                 }
2445                 if ((sta_id != IWL_INVALID_STATION)) {
2446                         lq_sta->lq.sta_id = sta_id;
2447                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2448                         lq_sta->ibss_sta_added = 1;
2449                         rs_initialize_lq(priv, conf, sta, lq_sta);
2450                 }
2451         }
2452
2453         if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2454                 rate_idx -= IWL_FIRST_OFDM_RATE;
2455                 /* 6M and 9M shared same MCS index */
2456                 rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2457                 if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2458                     IWL_RATE_MIMO3_6M_PLCP)
2459                         rate_idx = rate_idx + (2 * MCS_INDEX_PER_STREAM);
2460                 else if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2461                          IWL_RATE_MIMO2_6M_PLCP)
2462                         rate_idx = rate_idx + MCS_INDEX_PER_STREAM;
2463                 info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2464                 if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2465                         info->control.rates[0].flags |= IEEE80211_TX_RC_SHORT_GI;
2466                 if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2467                         info->control.rates[0].flags |= IEEE80211_TX_RC_DUP_DATA;
2468                 if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2469                         info->control.rates[0].flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
2470                 if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2471                         info->control.rates[0].flags |= IEEE80211_TX_RC_GREEN_FIELD;
2472         } else {
2473                 /* Check for invalid rates */
2474                 if ((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT_LEGACY) ||
2475                                 ((sband->band == IEEE80211_BAND_5GHZ) &&
2476                                  (rate_idx < IWL_FIRST_OFDM_RATE)))
2477                         rate_idx = rate_lowest_index(sband, sta);
2478                 /* On valid 5 GHz rate, adjust index */
2479                 else if (sband->band == IEEE80211_BAND_5GHZ)
2480                         rate_idx -= IWL_FIRST_OFDM_RATE;
2481                 info->control.rates[0].flags = 0;
2482         }
2483         info->control.rates[0].idx = rate_idx;
2484
2485 }
2486
2487 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2488                           gfp_t gfp)
2489 {
2490         struct iwl_lq_sta *lq_sta;
2491         struct iwl_station_priv *sta_priv = (struct iwl_station_priv *) sta->drv_priv;
2492         struct iwl_priv *priv;
2493
2494         priv = (struct iwl_priv *)priv_rate;
2495         IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2496
2497         lq_sta = &sta_priv->lq_sta;
2498
2499         return lq_sta;
2500 }
2501
2502 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2503                          struct ieee80211_sta *sta, void *priv_sta)
2504 {
2505         int i, j;
2506         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2507         struct ieee80211_conf *conf = &priv->hw->conf;
2508         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2509         struct iwl_lq_sta *lq_sta = priv_sta;
2510
2511         lq_sta->lq.sta_id = 0xff;
2512
2513         for (j = 0; j < LQ_SIZE; j++)
2514                 for (i = 0; i < IWL_RATE_COUNT; i++)
2515                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2516
2517         lq_sta->flush_timer = 0;
2518         lq_sta->supp_rates = sta->supp_rates[sband->band];
2519         for (j = 0; j < LQ_SIZE; j++)
2520                 for (i = 0; i < IWL_RATE_COUNT; i++)
2521                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2522
2523         IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init ***\n");
2524         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2525          * the lowest or the highest rate.. Could consider using RSSI from
2526          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2527          * after assoc.. */
2528
2529         lq_sta->ibss_sta_added = 0;
2530         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2531                 u8 sta_id = iwl_find_station(priv,
2532                                                                 sta->addr);
2533
2534                 /* for IBSS the call are from tasklet */
2535                 IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2536
2537                 if (sta_id == IWL_INVALID_STATION) {
2538                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2539                         sta_id = iwl_add_station(priv, sta->addr, false,
2540                                                 CMD_ASYNC, ht_cap);
2541                 }
2542                 if ((sta_id != IWL_INVALID_STATION)) {
2543                         lq_sta->lq.sta_id = sta_id;
2544                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2545                 }
2546                 /* FIXME: this is w/a remove it later */
2547                 priv->assoc_station_added = 1;
2548         }
2549
2550         lq_sta->is_dup = 0;
2551         lq_sta->max_rate_idx = -1;
2552         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2553         lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2554         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2555         lq_sta->active_rate_basic = priv->active_rate_basic;
2556         lq_sta->band = priv->band;
2557         /*
2558          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2559          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2560          */
2561         lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
2562         lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
2563         lq_sta->active_siso_rate &= ~((u16)0x2);
2564         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2565
2566         /* Same here */
2567         lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
2568         lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
2569         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2570         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2571
2572         lq_sta->active_mimo3_rate = ht_cap->mcs.rx_mask[2] << 1;
2573         lq_sta->active_mimo3_rate |= ht_cap->mcs.rx_mask[2] & 0x1;
2574         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2575         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2576
2577         IWL_DEBUG_RATE(priv, "SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2578                      lq_sta->active_siso_rate,
2579                      lq_sta->active_mimo2_rate,
2580                      lq_sta->active_mimo3_rate);
2581
2582         /* These values will be overridden later */
2583         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2584         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2585
2586         /* as default allow aggregation for all tids */
2587         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2588         lq_sta->drv = priv;
2589
2590         /* Set last_txrate_idx to lowest rate */
2591         lq_sta->last_txrate_idx = rate_lowest_index(sband, sta);
2592         if (sband->band == IEEE80211_BAND_5GHZ)
2593                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2594         lq_sta->is_agg = 0;
2595
2596         rs_initialize_lq(priv, conf, sta, lq_sta);
2597 }
2598
2599 static void rs_fill_link_cmd(struct iwl_priv *priv,
2600                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2601 {
2602         struct iwl_scale_tbl_info tbl_type;
2603         int index = 0;
2604         int rate_idx;
2605         int repeat_rate = 0;
2606         u8 ant_toggle_cnt = 0;
2607         u8 use_ht_possible = 1;
2608         u8 valid_tx_ant = 0;
2609         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2610
2611         /* Override starting rate (index 0) if needed for debug purposes */
2612         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2613
2614         /* Interpret new_rate (rate_n_flags) */
2615         memset(&tbl_type, 0, sizeof(tbl_type));
2616         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2617                                   &tbl_type, &rate_idx);
2618
2619         /* How many times should we repeat the initial rate? */
2620         if (is_legacy(tbl_type.lq_type)) {
2621                 ant_toggle_cnt = 1;
2622                 repeat_rate = IWL_NUMBER_TRY;
2623         } else {
2624                 repeat_rate = IWL_HT_NUMBER_TRY;
2625         }
2626
2627         lq_cmd->general_params.mimo_delimiter =
2628                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2629
2630         /* Fill 1st table entry (index 0) */
2631         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2632
2633         if (num_of_ant(tbl_type.ant_type) == 1) {
2634                 lq_cmd->general_params.single_stream_ant_msk =
2635                                                 tbl_type.ant_type;
2636         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2637                 lq_cmd->general_params.dual_stream_ant_msk =
2638                                                 tbl_type.ant_type;
2639         } /* otherwise we don't modify the existing value */
2640
2641         index++;
2642         repeat_rate--;
2643
2644         if (priv)
2645                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2646
2647         /* Fill rest of rate table */
2648         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2649                 /* Repeat initial/next rate.
2650                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2651                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2652                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2653                         if (is_legacy(tbl_type.lq_type)) {
2654                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2655                                         ant_toggle_cnt++;
2656                                 else if (priv &&
2657                                          rs_toggle_antenna(valid_tx_ant,
2658                                                         &new_rate, &tbl_type))
2659                                         ant_toggle_cnt = 1;
2660 }
2661
2662                         /* Override next rate if needed for debug purposes */
2663                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2664
2665                         /* Fill next table entry */
2666                         lq_cmd->rs_table[index].rate_n_flags =
2667                                         cpu_to_le32(new_rate);
2668                         repeat_rate--;
2669                         index++;
2670                 }
2671
2672                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2673                                                 &rate_idx);
2674
2675                 /* Indicate to uCode which entries might be MIMO.
2676                  * If initial rate was MIMO, this will finally end up
2677                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2678                 if (is_mimo(tbl_type.lq_type))
2679                         lq_cmd->general_params.mimo_delimiter = index;
2680
2681                 /* Get next rate */
2682                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2683                                              use_ht_possible);
2684
2685                 /* How many times should we repeat the next rate? */
2686                 if (is_legacy(tbl_type.lq_type)) {
2687                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2688                                 ant_toggle_cnt++;
2689                         else if (priv &&
2690                                  rs_toggle_antenna(valid_tx_ant,
2691                                                    &new_rate, &tbl_type))
2692                                 ant_toggle_cnt = 1;
2693
2694                         repeat_rate = IWL_NUMBER_TRY;
2695                 } else {
2696                         repeat_rate = IWL_HT_NUMBER_TRY;
2697                 }
2698
2699                 /* Don't allow HT rates after next pass.
2700                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2701                 use_ht_possible = 0;
2702
2703                 /* Override next rate if needed for debug purposes */
2704                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2705
2706                 /* Fill next table entry */
2707                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2708
2709                 index++;
2710                 repeat_rate--;
2711         }
2712
2713         lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
2714         lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2715         lq_cmd->agg_params.agg_time_limit =
2716                 cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2717 }
2718
2719 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2720 {
2721         return hw->priv;
2722 }
2723 /* rate scale requires free function to be implemented */
2724 static void rs_free(void *priv_rate)
2725 {
2726         return;
2727 }
2728
2729 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2730                         void *priv_sta)
2731 {
2732         struct iwl_priv *priv __maybe_unused = priv_r;
2733
2734         IWL_DEBUG_RATE(priv, "enter\n");
2735         IWL_DEBUG_RATE(priv, "leave\n");
2736 }
2737
2738
2739 #ifdef CONFIG_MAC80211_DEBUGFS
2740 static int open_file_generic(struct inode *inode, struct file *file)
2741 {
2742         file->private_data = inode->i_private;
2743         return 0;
2744 }
2745 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2746                              u32 *rate_n_flags, int index)
2747 {
2748         struct iwl_priv *priv;
2749         u8 valid_tx_ant;
2750         u8 ant_sel_tx;
2751
2752         priv = lq_sta->drv;
2753         valid_tx_ant = priv->hw_params.valid_tx_ant;
2754         if (lq_sta->dbg_fixed_rate) {
2755                 ant_sel_tx =
2756                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2757                   >> RATE_MCS_ANT_POS);
2758                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2759                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2760                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2761                 } else {
2762                         lq_sta->dbg_fixed_rate = 0;
2763                         IWL_ERR(priv,
2764                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2765                             ant_sel_tx, valid_tx_ant);
2766                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2767                 }
2768         } else {
2769                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2770         }
2771 }
2772
2773 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2774                         const char __user *user_buf, size_t count, loff_t *ppos)
2775 {
2776         struct iwl_lq_sta *lq_sta = file->private_data;
2777         struct iwl_priv *priv;
2778         char buf[64];
2779         int buf_size;
2780         u32 parsed_rate;
2781
2782         priv = lq_sta->drv;
2783         memset(buf, 0, sizeof(buf));
2784         buf_size = min(count, sizeof(buf) -  1);
2785         if (copy_from_user(buf, user_buf, buf_size))
2786                 return -EFAULT;
2787
2788         if (sscanf(buf, "%x", &parsed_rate) == 1)
2789                 lq_sta->dbg_fixed_rate = parsed_rate;
2790         else
2791                 lq_sta->dbg_fixed_rate = 0;
2792
2793         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2794         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2795         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2796         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2797
2798         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2799                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2800
2801         if (lq_sta->dbg_fixed_rate) {
2802                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2803                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2804         }
2805
2806         return count;
2807 }
2808
2809 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2810                         char __user *user_buf, size_t count, loff_t *ppos)
2811 {
2812         char *buff;
2813         int desc = 0;
2814         int i = 0;
2815         int index = 0;
2816         ssize_t ret;
2817
2818         struct iwl_lq_sta *lq_sta = file->private_data;
2819         struct iwl_priv *priv;
2820         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2821
2822         priv = lq_sta->drv;
2823         buff = kmalloc(1024, GFP_KERNEL);
2824         if (!buff)
2825                 return -ENOMEM;
2826
2827         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2828         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2829                         lq_sta->total_failed, lq_sta->total_success,
2830                         lq_sta->active_legacy_rate);
2831         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2832                         lq_sta->dbg_fixed_rate);
2833         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2834             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2835             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2836             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2837         desc += sprintf(buff+desc, "lq type %s\n",
2838            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2839         if (is_Ht(tbl->lq_type)) {
2840                 desc += sprintf(buff+desc, " %s",
2841                    (is_siso(tbl->lq_type)) ? "SISO" :
2842                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2843                    desc += sprintf(buff+desc, " %s",
2844                    (tbl->is_ht40) ? "40MHz" : "20MHz");
2845                    desc += sprintf(buff+desc, " %s %s %s\n", (tbl->is_SGI) ? "SGI" : "",
2846                    (lq_sta->is_green) ? "GF enabled" : "",
2847                    (lq_sta->is_agg) ? "AGG on" : "");
2848         }
2849         desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2850                 lq_sta->last_rate_n_flags);
2851         desc += sprintf(buff+desc, "general:"
2852                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2853                 lq_sta->lq.general_params.flags,
2854                 lq_sta->lq.general_params.mimo_delimiter,
2855                 lq_sta->lq.general_params.single_stream_ant_msk,
2856                 lq_sta->lq.general_params.dual_stream_ant_msk);
2857
2858         desc += sprintf(buff+desc, "agg:"
2859                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2860                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2861                         lq_sta->lq.agg_params.agg_dis_start_th,
2862                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2863
2864         desc += sprintf(buff+desc,
2865                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2866                         lq_sta->lq.general_params.start_rate_index[0],
2867                         lq_sta->lq.general_params.start_rate_index[1],
2868                         lq_sta->lq.general_params.start_rate_index[2],
2869                         lq_sta->lq.general_params.start_rate_index[3]);
2870
2871         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2872                 index = iwl_hwrate_to_plcp_idx(
2873                         le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2874                 if (is_legacy(tbl->lq_type)) {
2875                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2876                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2877                                 iwl_rate_mcs[index].mbps);
2878                 } else {
2879                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps (%s)\n",
2880                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2881                                 iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
2882                 }
2883         }
2884
2885         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2886         kfree(buff);
2887         return ret;
2888 }
2889
2890 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2891         .write = rs_sta_dbgfs_scale_table_write,
2892         .read = rs_sta_dbgfs_scale_table_read,
2893         .open = open_file_generic,
2894 };
2895 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2896                         char __user *user_buf, size_t count, loff_t *ppos)
2897 {
2898         char *buff;
2899         int desc = 0;
2900         int i, j;
2901         ssize_t ret;
2902
2903         struct iwl_lq_sta *lq_sta = file->private_data;
2904
2905         buff = kmalloc(1024, GFP_KERNEL);
2906         if (!buff)
2907                 return -ENOMEM;
2908
2909         for (i = 0; i < LQ_SIZE; i++) {
2910                 desc += sprintf(buff+desc,
2911                                 "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
2912                                 "rate=0x%X\n",
2913                                 lq_sta->active_tbl == i ? "*" : "x",
2914                                 lq_sta->lq_info[i].lq_type,
2915                                 lq_sta->lq_info[i].is_SGI,
2916                                 lq_sta->lq_info[i].is_ht40,
2917                                 lq_sta->lq_info[i].is_dup,
2918                                 lq_sta->is_green,
2919                                 lq_sta->lq_info[i].current_rate);
2920                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2921                         desc += sprintf(buff+desc,
2922                                 "counter=%d success=%d %%=%d\n",
2923                                 lq_sta->lq_info[i].win[j].counter,
2924                                 lq_sta->lq_info[i].win[j].success_counter,
2925                                 lq_sta->lq_info[i].win[j].success_ratio);
2926                 }
2927         }
2928         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2929         kfree(buff);
2930         return ret;
2931 }
2932
2933 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2934         .read = rs_sta_dbgfs_stats_table_read,
2935         .open = open_file_generic,
2936 };
2937
2938 static ssize_t rs_sta_dbgfs_rate_scale_data_read(struct file *file,
2939                         char __user *user_buf, size_t count, loff_t *ppos)
2940 {
2941         char buff[120];
2942         int desc = 0;
2943         ssize_t ret;
2944
2945         struct iwl_lq_sta *lq_sta = file->private_data;
2946         struct iwl_priv *priv;
2947         struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
2948
2949         priv = lq_sta->drv;
2950
2951         if (is_Ht(tbl->lq_type))
2952                 desc += sprintf(buff+desc,
2953                                 "Bit Rate= %d Mb/s\n",
2954                                 tbl->expected_tpt[lq_sta->last_txrate_idx]);
2955         else
2956                 desc += sprintf(buff+desc,
2957                                 "Bit Rate= %d Mb/s\n",
2958                                 iwl_rates[lq_sta->last_txrate_idx].ieee >> 1);
2959         desc += sprintf(buff+desc,
2960                         "Signal Level= %d dBm\tNoise Level= %d dBm\n",
2961                         priv->last_rx_rssi, priv->last_rx_noise);
2962         desc += sprintf(buff+desc,
2963                         "Tsf= 0x%llx\tBeacon time= 0x%08X\n",
2964                         priv->last_tsf, priv->last_beacon_time);
2965
2966         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2967         return ret;
2968 }
2969
2970 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
2971         .read = rs_sta_dbgfs_rate_scale_data_read,
2972         .open = open_file_generic,
2973 };
2974
2975 static void rs_add_debugfs(void *priv, void *priv_sta,
2976                                         struct dentry *dir)
2977 {
2978         struct iwl_lq_sta *lq_sta = priv_sta;
2979         lq_sta->rs_sta_dbgfs_scale_table_file =
2980                 debugfs_create_file("rate_scale_table", S_IRUSR | S_IWUSR, dir,
2981                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2982         lq_sta->rs_sta_dbgfs_stats_table_file =
2983                 debugfs_create_file("rate_stats_table", S_IRUSR, dir,
2984                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2985         lq_sta->rs_sta_dbgfs_rate_scale_data_file =
2986                 debugfs_create_file("rate_scale_data", S_IRUSR, dir,
2987                         lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
2988         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2989                 debugfs_create_u8("tx_agg_tid_enable", S_IRUSR | S_IWUSR, dir,
2990                 &lq_sta->tx_agg_tid_en);
2991
2992 }
2993
2994 static void rs_remove_debugfs(void *priv, void *priv_sta)
2995 {
2996         struct iwl_lq_sta *lq_sta = priv_sta;
2997         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2998         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2999         debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
3000         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
3001 }
3002 #endif
3003
3004 static struct rate_control_ops rs_ops = {
3005         .module = NULL,
3006         .name = RS_NAME,
3007         .tx_status = rs_tx_status,
3008         .get_rate = rs_get_rate,
3009         .rate_init = rs_rate_init,
3010         .alloc = rs_alloc,
3011         .free = rs_free,
3012         .alloc_sta = rs_alloc_sta,
3013         .free_sta = rs_free_sta,
3014 #ifdef CONFIG_MAC80211_DEBUGFS
3015         .add_sta_debugfs = rs_add_debugfs,
3016         .remove_sta_debugfs = rs_remove_debugfs,
3017 #endif
3018 };
3019
3020 int iwlagn_rate_control_register(void)
3021 {
3022         return ieee80211_rate_control_register(&rs_ops);
3023 }
3024
3025 void iwlagn_rate_control_unregister(void)
3026 {
3027         ieee80211_rate_control_unregister(&rs_ops);
3028 }
3029