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