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 <[email protected]>
  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         /* Treat uninitialized rate scaling data same as non-existing. */
 773         if (!lq_sta) {
 774                 IWL_DEBUG_RATE(priv, "Station rate scaling not created yet.\n");
 775                 return;
 776         } else if (!lq_sta->drv) {
 777                 IWL_DEBUG_RATE(priv, "Rate scaling not initialized yet.\n");
 778                 return;
 779         }
 780
 781         if (!ieee80211_is_data(hdr->frame_control) ||
 782             info->flags & IEEE80211_TX_CTL_NO_ACK)
 783                 return;
 784
 785         /* This packet was aggregated but doesn't carry status info */
 786         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 787             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 788                 return;
 789
 790         /*
 791          * Ignore this Tx frame response if its initial rate doesn't match
 792          * that of latest Link Quality command.  There may be stragglers
 793          * from a previous Link Quality command, but we're no longer interested
 794          * in those; they're either from the "active" mode while we're trying
 795          * to check "search" mode, or a prior "search" mode after we've moved
 796          * to a new "search" mode (which might become the new "active" mode).
 797          */
 798         table = &lq_sta->lq;
 799         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 800         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 801         if (priv->band == IEEE80211_BAND_5GHZ)
 802                 rs_index -= IWL_FIRST_OFDM_RATE;
 803         mac_flags = info->status.rates[0].flags;
 804         mac_index = info->status.rates[0].idx;
 805         /* For HT packets, map MCS to PLCP */
 806         if (mac_flags & IEEE80211_TX_RC_MCS) {
 807                 mac_index &= RATE_MCS_CODE_MSK; /* Remove # of streams */
 808                 if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE))
 809                         mac_index++;
 810                 /*
 811                  * mac80211 HT index is always zero-indexed; we need to move
 812                  * HT OFDM rates after CCK rates in 2.4 GHz band
 813                  */
 814                 if (priv->band == IEEE80211_BAND_2GHZ)
 815                         mac_index += IWL_FIRST_OFDM_RATE;
 816         }
 817         /* Here we actually compare this rate to the latest LQ command */
 818         if ((mac_index < 0) ||
 819             (tbl_type.is_SGI != !!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) ||
 820             (tbl_type.is_ht40 != !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 821             (tbl_type.is_dup != !!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) ||
 822             (tbl_type.ant_type != info->antenna_sel_tx) ||
 823             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(mac_flags & IEEE80211_TX_RC_MCS)) ||
 824             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 825             (rs_index != mac_index)) {
 826                 IWL_DEBUG_RATE(priv, "initial rate %d does not match %d (0x%x)\n", mac_index, rs_index, tx_rate);
 827                 /*
 828                  * Since rates mis-match, the last LQ command may have failed.
 829                  * After IWL_MISSED_RATE_MAX mis-matches, resync the uCode with
 830                  * ... driver.
 831                  */
 832                 lq_sta->missed_rate_counter++;
 833                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 834                         lq_sta->missed_rate_counter = 0;
 835                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC, false);
 836                 }
 837                 /* Regardless, ignore this status info for outdated rate */
 838                 return;
 839         } else
 840                 /* Rate did match, so reset the missed_rate_counter */
 841                 lq_sta->missed_rate_counter = 0;
 842
 843         /* Figure out if rate scale algorithm is in active or search table */
 844         if (table_type_matches(&tbl_type,
 845                                 &(lq_sta->lq_info[lq_sta->active_tbl]))) {
 846                 curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 847                 other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 848         } else if (table_type_matches(&tbl_type,
 849                                 &lq_sta->lq_info[1 - lq_sta->active_tbl])) {
 850                 curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 851                 other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 852         } else {
 853                 IWL_DEBUG_RATE(priv, "Neither active nor search matches tx rate\n");
 854                 return;
 855         }
 856         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 857
 858         /*
 859          * Updating the frame history depends on whether packets were
 860          * aggregated.
 861          *
 862          * For aggregation, all packets were transmitted at the same rate, the
 863          * first index into rate scale table.
 864          */
 865         if (info->flags & IEEE80211_TX_STAT_AMPDU) {
 866                 tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 867                 rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type,
 868                                 &rs_index);
 869                 tpt = get_expected_tpt(curr_tbl, rs_index);
 870                 rs_collect_tx_data(window, rs_index, tpt,
 871                                    info->status.ampdu_ack_len,
 872                                    info->status.ampdu_ack_map);
 873
 874                 /* Update success/fail counts if not searching for new mode */
 875                 if (lq_sta->stay_in_tbl) {
 876                         lq_sta->total_success += info->status.ampdu_ack_map;
 877                         lq_sta->total_failed += (info->status.ampdu_ack_len -
 878                                         info->status.ampdu_ack_map);
 879                 }
 880         } else {
 881         /*
 882          * For legacy, update frame history with for each Tx retry.
 883          */
 884                 retries = info->status.rates[0].count - 1;
 885                 /* HW doesn't send more than 15 retries */
 886                 retries = min(retries, 15);
 887
 888                 /* The last transmission may have been successful */
 889                 legacy_success = !!(info->flags & IEEE80211_TX_STAT_ACK);
 890                 /* Collect data for each rate used during failed TX attempts */
 891                 for (i = 0; i <= retries; ++i) {
 892                         tx_rate = le32_to_cpu(table->rs_table[i].rate_n_flags);
 893                         rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 894                                         &tbl_type, &rs_index);
 895                         /*
 896                          * Only collect stats if retried rate is in the same RS
 897                          * table as active/search.
 898                          */
 899                         if (table_type_matches(&tbl_type, curr_tbl))
 900                                 tpt = get_expected_tpt(curr_tbl, rs_index);
 901                         else if (table_type_matches(&tbl_type, other_tbl))
 902                                 tpt = get_expected_tpt(other_tbl, rs_index);
 903                         else
 904                                 continue;
 905
 906                         /* Constants mean 1 transmission, 0 successes */
 907                         if (i < retries)
 908                                 rs_collect_tx_data(window, rs_index, tpt, 1,
 909                                                 0);
 910                         else
 911                                 rs_collect_tx_data(window, rs_index, tpt, 1,
 912                                                 legacy_success);
 913                 }
 914
 915                 /* Update success/fail counts if not searching for new mode */
 916                 if (lq_sta->stay_in_tbl) {
 917                         lq_sta->total_success += legacy_success;
 918                         lq_sta->total_failed += retries + (1 - legacy_success);
 919                 }
 920         }
 921         /* The last TX rate is cached in lq_sta; it's set in if/else above */
 922         lq_sta->last_rate_n_flags = tx_rate;
 923
 924         /* See if there's a better rate or modulation mode to try. */
 925         if (sta && sta->supp_rates[sband->band])
 926                 rs_rate_scale_perform(priv, skb, sta, lq_sta);
 927 }
 928
 929 /*
 930  * Begin a period of staying with a selected modulation mode.
 931  * Set "stay_in_tbl" flag to prevent any mode switches.
 932  * Set frame tx success limits according to legacy vs. high-throughput,
 933  * and reset overall (spanning all rates) tx success history statistics.
 934  * These control how long we stay using same modulation mode before
 935  * searching for a new mode.
 936  */
 937 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
 938                                  struct iwl_lq_sta *lq_sta)
 939 {
 940         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
 941         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
 942         if (is_legacy) {
 943                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
 944                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
 945                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
 946         } else {
 947                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
 948                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
 949                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
 950         }
 951         lq_sta->table_count = 0;
 952         lq_sta->total_failed = 0;
 953         lq_sta->total_success = 0;
 954         lq_sta->flush_timer = jiffies;
 955         lq_sta->action_counter = 0;
 956 }
 957
 958 /*
 959  * Find correct throughput table for given mode of modulation
 960  */
 961 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
 962                                       struct iwl_scale_tbl_info *tbl)
 963 {
 964         /* Used to choose among HT tables */
 965         s32 (*ht_tbl_pointer)[IWL_RATE_COUNT];
 966
 967         /* Check for invalid LQ type */
 968         if (WARN_ON_ONCE(!is_legacy(tbl->lq_type) && !is_Ht(tbl->lq_type))) {
 969                 tbl->expected_tpt = expected_tpt_legacy;
 970                 return;
 971         }
 972
 973         /* Legacy rates have only one table */
 974         if (is_legacy(tbl->lq_type)) {
 975                 tbl->expected_tpt = expected_tpt_legacy;
 976                 return;
 977         }
 978
 979         /* Choose among many HT tables depending on number of streams
 980          * (SISO/MIMO2/MIMO3), channel width (20/40), SGI, and aggregation
 981          * status */
 982         if (is_siso(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 983                 ht_tbl_pointer = expected_tpt_siso20MHz;
 984         else if (is_siso(tbl->lq_type))
 985                 ht_tbl_pointer = expected_tpt_siso40MHz;
 986         else if (is_mimo2(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 987                 ht_tbl_pointer = expected_tpt_mimo2_20MHz;
 988         else if (is_mimo2(tbl->lq_type))
 989                 ht_tbl_pointer = expected_tpt_mimo2_40MHz;
 990         else if (is_mimo3(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
 991                 ht_tbl_pointer = expected_tpt_mimo3_20MHz;
 992         else /* if (is_mimo3(tbl->lq_type)) <-- must be true */
 993                 ht_tbl_pointer = expected_tpt_mimo3_40MHz;
 994
 995         if (!tbl->is_SGI && !lq_sta->is_agg)            /* Normal */
 996                 tbl->expected_tpt = ht_tbl_pointer[0];
 997         else if (tbl->is_SGI && !lq_sta->is_agg)        /* SGI */
 998                 tbl->expected_tpt = ht_tbl_pointer[1];
 999         else if (!tbl->is_SGI && lq_sta->is_agg)        /* AGG */
1000                 tbl->expected_tpt = ht_tbl_pointer[2];
1001         else                                            /* AGG+SGI */
1002                 tbl->expected_tpt = ht_tbl_pointer[3];
1003 }
1004
1005 /*
1006  * Find starting rate for new "search" high-throughput mode of modulation.
1007  * Goal is to find lowest expected rate (under perfect conditions) that is
1008  * above the current measured throughput of "active" mode, to give new mode
1009  * a fair chance to prove itself without too many challenges.
1010  *
1011  * This gets called when transitioning to more aggressive modulation
1012  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1013  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1014  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1015  * bit rate will typically need to increase, but not if performance was bad.
1016  */
1017 static s32 rs_get_best_rate(struct iwl_priv *priv,
1018                             struct iwl_lq_sta *lq_sta,
1019                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1020                             u16 rate_mask, s8 index)
1021 {
1022         /* "active" values */
1023         struct iwl_scale_tbl_info *active_tbl =
1024             &(lq_sta->lq_info[lq_sta->active_tbl]);
1025         s32 active_sr = active_tbl->win[index].success_ratio;
1026         s32 active_tpt = active_tbl->expected_tpt[index];
1027
1028         /* expected "search" throughput */
1029         s32 *tpt_tbl = tbl->expected_tpt;
1030
1031         s32 new_rate, high, low, start_hi;
1032         u16 high_low;
1033         s8 rate = index;
1034
1035         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1036
1037         for (; ;) {
1038                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1039                                                 tbl->lq_type);
1040
1041                 low = high_low & 0xff;
1042                 high = (high_low >> 8) & 0xff;
1043
1044                 /*
1045                  * Lower the "search" bit rate, to give new "search" mode
1046                  * approximately the same throughput as "active" if:
1047                  *
1048                  * 1) "Active" mode has been working modestly well (but not
1049                  *    great), and expected "search" throughput (under perfect
1050                  *    conditions) at candidate rate is above the actual
1051                  *    measured "active" throughput (but less than expected
1052                  *    "active" throughput under perfect conditions).
1053                  * OR
1054                  * 2) "Active" mode has been working perfectly or very well
1055                  *    and expected "search" throughput (under perfect
1056                  *    conditions) at candidate rate is above expected
1057                  *    "active" throughput (under perfect conditions).
1058                  */
1059                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1060                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1061                       (active_sr <= IWL_RATE_HIGH_TH) &&
1062                       (tpt_tbl[rate] <= active_tpt))) ||
1063                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1064                      (tpt_tbl[rate] > active_tpt))) {
1065
1066                         /* (2nd or later pass)
1067                          * If we've already tried to raise the rate, and are
1068                          * now trying to lower it, use the higher rate. */
1069                         if (start_hi != IWL_RATE_INVALID) {
1070                                 new_rate = start_hi;
1071                                 break;
1072                         }
1073
1074                         new_rate = rate;
1075
1076                         /* Loop again with lower rate */
1077                         if (low != IWL_RATE_INVALID)
1078                                 rate = low;
1079
1080                         /* Lower rate not available, use the original */
1081                         else
1082                                 break;
1083
1084                 /* Else try to raise the "search" rate to match "active" */
1085                 } else {
1086                         /* (2nd or later pass)
1087                          * If we've already tried to lower the rate, and are
1088                          * now trying to raise it, use the lower rate. */
1089                         if (new_rate != IWL_RATE_INVALID)
1090                                 break;
1091
1092                         /* Loop again with higher rate */
1093                         else if (high != IWL_RATE_INVALID) {
1094                                 start_hi = high;
1095                                 rate = high;
1096
1097                         /* Higher rate not available, use the original */
1098                         } else {
1099                                 new_rate = rate;
1100                                 break;
1101                         }
1102                 }
1103         }
1104
1105         return new_rate;
1106 }
1107
1108 /*
1109  * Set up search table for MIMO2
1110  */
1111 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1112                              struct iwl_lq_sta *lq_sta,
1113                              struct ieee80211_conf *conf,
1114                              struct ieee80211_sta *sta,
1115                              struct iwl_scale_tbl_info *tbl, int index)
1116 {
1117         u16 rate_mask;
1118         s32 rate;
1119         s8 is_green = lq_sta->is_green;
1120
1121         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1122                 return -1;
1123
1124         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1125                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1126                 return -1;
1127
1128         /* Need both Tx chains/antennas to support MIMO */
1129         if (priv->hw_params.tx_chains_num < 2)
1130                 return -1;
1131
1132         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1133
1134         tbl->lq_type = LQ_MIMO2;
1135         tbl->is_dup = lq_sta->is_dup;
1136         tbl->action = 0;
1137         tbl->max_search = IWL_MAX_SEARCH;
1138         rate_mask = lq_sta->active_mimo2_rate;
1139
1140         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1141                 tbl->is_ht40 = 1;
1142         else
1143                 tbl->is_ht40 = 0;
1144
1145         rs_set_expected_tpt_table(lq_sta, tbl);
1146
1147         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1148
1149         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1150         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1151                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1152                                                 rate, rate_mask);
1153                 return -1;
1154         }
1155         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1156
1157         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1158                      tbl->current_rate, is_green);
1159         return 0;
1160 }
1161
1162 /*
1163  * Set up search table for MIMO3
1164  */
1165 static int rs_switch_to_mimo3(struct iwl_priv *priv,
1166                              struct iwl_lq_sta *lq_sta,
1167                              struct ieee80211_conf *conf,
1168                              struct ieee80211_sta *sta,
1169                              struct iwl_scale_tbl_info *tbl, int index)
1170 {
1171         u16 rate_mask;
1172         s32 rate;
1173         s8 is_green = lq_sta->is_green;
1174
1175         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1176                 return -1;
1177
1178         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1179                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1180                 return -1;
1181
1182         /* Need both Tx chains/antennas to support MIMO */
1183         if (priv->hw_params.tx_chains_num < 3)
1184                 return -1;
1185
1186         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO3\n");
1187
1188         tbl->lq_type = LQ_MIMO3;
1189         tbl->is_dup = lq_sta->is_dup;
1190         tbl->action = 0;
1191         tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
1192         rate_mask = lq_sta->active_mimo3_rate;
1193
1194         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1195                 tbl->is_ht40 = 1;
1196         else
1197                 tbl->is_ht40 = 0;
1198
1199         rs_set_expected_tpt_table(lq_sta, tbl);
1200
1201         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1202
1203         IWL_DEBUG_RATE(priv, "LQ: MIMO3 best rate %d mask %X\n",
1204                 rate, rate_mask);
1205         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1206                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1207                                                 rate, rate_mask);
1208                 return -1;
1209         }
1210         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1211
1212         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1213                      tbl->current_rate, is_green);
1214         return 0;
1215 }
1216
1217 /*
1218  * Set up search table for SISO
1219  */
1220 static int rs_switch_to_siso(struct iwl_priv *priv,
1221                              struct iwl_lq_sta *lq_sta,
1222                              struct ieee80211_conf *conf,
1223                              struct ieee80211_sta *sta,
1224                              struct iwl_scale_tbl_info *tbl, int index)
1225 {
1226         u16 rate_mask;
1227         u8 is_green = lq_sta->is_green;
1228         s32 rate;
1229
1230         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1231                 return -1;
1232
1233         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1234
1235         tbl->is_dup = lq_sta->is_dup;
1236         tbl->lq_type = LQ_SISO;
1237         tbl->action = 0;
1238         tbl->max_search = IWL_MAX_SEARCH;
1239         rate_mask = lq_sta->active_siso_rate;
1240
1241         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1242                 tbl->is_ht40 = 1;
1243         else
1244                 tbl->is_ht40 = 0;
1245
1246         if (is_green)
1247                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1248
1249         rs_set_expected_tpt_table(lq_sta, tbl);
1250         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1251
1252         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1253         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1254                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1255                              rate, rate_mask);
1256                 return -1;
1257         }
1258         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1259         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1260                      tbl->current_rate, is_green);
1261         return 0;
1262 }
1263
1264 /*
1265  * Try to switch to new modulation mode from legacy
1266  */
1267 static int rs_move_legacy_other(struct iwl_priv *priv,
1268                                 struct iwl_lq_sta *lq_sta,
1269                                 struct ieee80211_conf *conf,
1270                                 struct ieee80211_sta *sta,
1271                                 int index)
1272 {
1273         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1274         struct iwl_scale_tbl_info *search_tbl =
1275                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1276         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1277         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1278                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1279         u8 start_action = tbl->action;
1280         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1281         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1282         int ret = 0;
1283         u8 update_search_tbl_counter = 0;
1284
1285         if (!iwl_ht_enabled(priv))
1286                 /* stay in Legacy */
1287                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1288         else if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1289                    tbl->action > IWL_LEGACY_SWITCH_SISO)
1290                 tbl->action = IWL_LEGACY_SWITCH_SISO;
1291         for (; ;) {
1292                 lq_sta->action_counter++;
1293                 switch (tbl->action) {
1294                 case IWL_LEGACY_SWITCH_ANTENNA1:
1295                 case IWL_LEGACY_SWITCH_ANTENNA2:
1296                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1297
1298                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1299                                                         tx_chains_num <= 1) ||
1300                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1301                                                         tx_chains_num <= 2))
1302                                 break;
1303
1304                         /* Don't change antenna if success has been great */
1305                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1306                                 break;
1307
1308                         /* Set up search table to try other antenna */
1309                         memcpy(search_tbl, tbl, sz);
1310
1311                         if (rs_toggle_antenna(valid_tx_ant,
1312                                 &search_tbl->current_rate, search_tbl)) {
1313                                 update_search_tbl_counter = 1;
1314                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1315                                 goto out;
1316                         }
1317                         break;
1318                 case IWL_LEGACY_SWITCH_SISO:
1319                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1320
1321                         /* Set up search table to try SISO */
1322                         memcpy(search_tbl, tbl, sz);
1323                         search_tbl->is_SGI = 0;
1324                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1325                                                  search_tbl, index);
1326                         if (!ret) {
1327                                 lq_sta->action_counter = 0;
1328                                 goto out;
1329                         }
1330
1331                         break;
1332                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1333                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1334                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1335                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1336
1337                         /* Set up search table to try MIMO */
1338                         memcpy(search_tbl, tbl, sz);
1339                         search_tbl->is_SGI = 0;
1340
1341                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1342                                 search_tbl->ant_type = ANT_AB;
1343                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1344                                 search_tbl->ant_type = ANT_AC;
1345                         else
1346                                 search_tbl->ant_type = ANT_BC;
1347
1348                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1349                                 break;
1350
1351                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1352                                                  search_tbl, index);
1353                         if (!ret) {
1354                                 lq_sta->action_counter = 0;
1355                                 goto out;
1356                         }
1357                         break;
1358
1359                 case IWL_LEGACY_SWITCH_MIMO3_ABC:
1360                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO3\n");
1361
1362                         /* Set up search table to try MIMO3 */
1363                         memcpy(search_tbl, tbl, sz);
1364                         search_tbl->is_SGI = 0;
1365
1366                         search_tbl->ant_type = ANT_ABC;
1367
1368                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1369                                 break;
1370
1371                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1372                                                  search_tbl, index);
1373                         if (!ret) {
1374                                 lq_sta->action_counter = 0;
1375                                 goto out;
1376                         }
1377                         break;
1378                 }
1379                 tbl->action++;
1380                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1381                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1382
1383                 if (tbl->action == start_action)
1384                         break;
1385
1386         }
1387         search_tbl->lq_type = LQ_NONE;
1388         return 0;
1389
1390 out:
1391         lq_sta->search_better_tbl = 1;
1392         tbl->action++;
1393         if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1394                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1395         if (update_search_tbl_counter)
1396                 search_tbl->action = tbl->action;
1397         return 0;
1398
1399 }
1400
1401 /*
1402  * Try to switch to new modulation mode from SISO
1403  */
1404 static int rs_move_siso_to_other(struct iwl_priv *priv,
1405                                  struct iwl_lq_sta *lq_sta,
1406                                  struct ieee80211_conf *conf,
1407                                  struct ieee80211_sta *sta, int index)
1408 {
1409         u8 is_green = lq_sta->is_green;
1410         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1411         struct iwl_scale_tbl_info *search_tbl =
1412                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1413         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1414         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1415         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1416                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1417         u8 start_action = tbl->action;
1418         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1419         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1420         u8 update_search_tbl_counter = 0;
1421         int ret;
1422
1423         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1424             tbl->action > IWL_SISO_SWITCH_ANTENNA2) {
1425                 /* stay in SISO */
1426                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1427         }
1428         for (;;) {
1429                 lq_sta->action_counter++;
1430                 switch (tbl->action) {
1431                 case IWL_SISO_SWITCH_ANTENNA1:
1432                 case IWL_SISO_SWITCH_ANTENNA2:
1433                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1434
1435                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1436                                                         tx_chains_num <= 1) ||
1437                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1438                                                         tx_chains_num <= 2))
1439                                 break;
1440
1441                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1442                                 break;
1443
1444                         memcpy(search_tbl, tbl, sz);
1445                         if (rs_toggle_antenna(valid_tx_ant,
1446                                        &search_tbl->current_rate, search_tbl)) {
1447                                 update_search_tbl_counter = 1;
1448                                 goto out;
1449                         }
1450                         break;
1451                 case IWL_SISO_SWITCH_MIMO2_AB:
1452                 case IWL_SISO_SWITCH_MIMO2_AC:
1453                 case IWL_SISO_SWITCH_MIMO2_BC:
1454                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1455                         memcpy(search_tbl, tbl, sz);
1456                         search_tbl->is_SGI = 0;
1457
1458                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1459                                 search_tbl->ant_type = ANT_AB;
1460                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1461                                 search_tbl->ant_type = ANT_AC;
1462                         else
1463                                 search_tbl->ant_type = ANT_BC;
1464
1465                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1466                                 break;
1467
1468                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1469                                                  search_tbl, index);
1470                         if (!ret)
1471                                 goto out;
1472                         break;
1473                 case IWL_SISO_SWITCH_GI:
1474                         if (!tbl->is_ht40 && !(ht_cap->cap &
1475                                                 IEEE80211_HT_CAP_SGI_20))
1476                                 break;
1477                         if (tbl->is_ht40 && !(ht_cap->cap &
1478                                                 IEEE80211_HT_CAP_SGI_40))
1479                                 break;
1480
1481                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1482
1483                         memcpy(search_tbl, tbl, sz);
1484                         if (is_green) {
1485                                 if (!tbl->is_SGI)
1486                                         break;
1487                                 else
1488                                         IWL_ERR(priv,
1489                                                 "SGI was set in GF+SISO\n");
1490                         }
1491                         search_tbl->is_SGI = !tbl->is_SGI;
1492                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1493                         if (tbl->is_SGI) {
1494                                 s32 tpt = lq_sta->last_tpt / 100;
1495                                 if (tpt >= search_tbl->expected_tpt[index])
1496                                         break;
1497                         }
1498                         search_tbl->current_rate =
1499                                 rate_n_flags_from_tbl(priv, search_tbl,
1500                                                       index, is_green);
1501                         update_search_tbl_counter = 1;
1502                         goto out;
1503                 case IWL_SISO_SWITCH_MIMO3_ABC:
1504                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO3\n");
1505                         memcpy(search_tbl, tbl, sz);
1506                         search_tbl->is_SGI = 0;
1507                         search_tbl->ant_type = ANT_ABC;
1508
1509                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1510                                 break;
1511
1512                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1513                                                  search_tbl, index);
1514                         if (!ret)
1515                                 goto out;
1516                         break;
1517                 }
1518                 tbl->action++;
1519                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1520                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1521
1522                 if (tbl->action == start_action)
1523                         break;
1524         }
1525         search_tbl->lq_type = LQ_NONE;
1526         return 0;
1527
1528  out:
1529         lq_sta->search_better_tbl = 1;
1530         tbl->action++;
1531         if (tbl->action > IWL_SISO_SWITCH_MIMO3_ABC)
1532                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1533         if (update_search_tbl_counter)
1534                 search_tbl->action = tbl->action;
1535
1536         return 0;
1537 }
1538
1539 /*
1540  * Try to switch to new modulation mode from MIMO2
1541  */
1542 static int rs_move_mimo2_to_other(struct iwl_priv *priv,
1543                                  struct iwl_lq_sta *lq_sta,
1544                                  struct ieee80211_conf *conf,
1545                                  struct ieee80211_sta *sta, int index)
1546 {
1547         s8 is_green = lq_sta->is_green;
1548         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1549         struct iwl_scale_tbl_info *search_tbl =
1550                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1551         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1552         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1553         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1554                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1555         u8 start_action = tbl->action;
1556         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1557         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1558         u8 update_search_tbl_counter = 0;
1559         int ret;
1560
1561         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1562             (tbl->action < IWL_MIMO2_SWITCH_SISO_A ||
1563              tbl->action > IWL_MIMO2_SWITCH_SISO_C)) {
1564                 /* switch in SISO */
1565                 tbl->action = IWL_MIMO2_SWITCH_SISO_A;
1566         }
1567         for (;;) {
1568                 lq_sta->action_counter++;
1569                 switch (tbl->action) {
1570                 case IWL_MIMO2_SWITCH_ANTENNA1:
1571                 case IWL_MIMO2_SWITCH_ANTENNA2:
1572                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1573
1574                         if (tx_chains_num <= 2)
1575                                 break;
1576
1577                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1578                                 break;
1579
1580                         memcpy(search_tbl, tbl, sz);
1581                         if (rs_toggle_antenna(valid_tx_ant,
1582                                        &search_tbl->current_rate, search_tbl)) {
1583                                 update_search_tbl_counter = 1;
1584                                 goto out;
1585                         }
1586                         break;
1587                 case IWL_MIMO2_SWITCH_SISO_A:
1588                 case IWL_MIMO2_SWITCH_SISO_B:
1589                 case IWL_MIMO2_SWITCH_SISO_C:
1590                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1591
1592                         /* Set up new search table for SISO */
1593                         memcpy(search_tbl, tbl, sz);
1594
1595                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1596                                 search_tbl->ant_type = ANT_A;
1597                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1598                                 search_tbl->ant_type = ANT_B;
1599                         else
1600                                 search_tbl->ant_type = ANT_C;
1601
1602                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1603                                 break;
1604
1605                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1606                                                  search_tbl, index);
1607                         if (!ret)
1608                                 goto out;
1609
1610                         break;
1611
1612                 case IWL_MIMO2_SWITCH_GI:
1613                         if (!tbl->is_ht40 && !(ht_cap->cap &
1614                                                 IEEE80211_HT_CAP_SGI_20))
1615                                 break;
1616                         if (tbl->is_ht40 && !(ht_cap->cap &
1617                                                 IEEE80211_HT_CAP_SGI_40))
1618                                 break;
1619
1620                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1621
1622                         /* Set up new search table for MIMO2 */
1623                         memcpy(search_tbl, tbl, sz);
1624                         search_tbl->is_SGI = !tbl->is_SGI;
1625                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1626                         /*
1627                          * If active table already uses the fastest possible
1628                          * modulation (dual stream with short guard interval),
1629                          * and it's working well, there's no need to look
1630                          * for a better type of modulation!
1631                          */
1632                         if (tbl->is_SGI) {
1633                                 s32 tpt = lq_sta->last_tpt / 100;
1634                                 if (tpt >= search_tbl->expected_tpt[index])
1635                                         break;
1636                         }
1637                         search_tbl->current_rate =
1638                                 rate_n_flags_from_tbl(priv, search_tbl,
1639                                                       index, is_green);
1640                         update_search_tbl_counter = 1;
1641                         goto out;
1642
1643                 case IWL_MIMO2_SWITCH_MIMO3_ABC:
1644                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to MIMO3\n");
1645                         memcpy(search_tbl, tbl, sz);
1646                         search_tbl->is_SGI = 0;
1647                         search_tbl->ant_type = ANT_ABC;
1648
1649                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1650                                 break;
1651
1652                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1653                                                  search_tbl, index);
1654                         if (!ret)
1655                                 goto out;
1656
1657                         break;
1658                 }
1659                 tbl->action++;
1660                 if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1661                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1662
1663                 if (tbl->action == start_action)
1664                         break;
1665         }
1666         search_tbl->lq_type = LQ_NONE;
1667         return 0;
1668  out:
1669         lq_sta->search_better_tbl = 1;
1670         tbl->action++;
1671         if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1672                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1673         if (update_search_tbl_counter)
1674                 search_tbl->action = tbl->action;
1675
1676         return 0;
1677
1678 }
1679
1680 /*
1681  * Try to switch to new modulation mode from MIMO3
1682  */
1683 static int rs_move_mimo3_to_other(struct iwl_priv *priv,
1684                                  struct iwl_lq_sta *lq_sta,
1685                                  struct ieee80211_conf *conf,
1686                                  struct ieee80211_sta *sta, int index)
1687 {
1688         s8 is_green = lq_sta->is_green;
1689         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1690         struct iwl_scale_tbl_info *search_tbl =
1691                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1692         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1693         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1694         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1695                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1696         u8 start_action = tbl->action;
1697         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1698         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1699         int ret;
1700         u8 update_search_tbl_counter = 0;
1701
1702         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1703             (tbl->action < IWL_MIMO3_SWITCH_SISO_A ||
1704              tbl->action > IWL_MIMO3_SWITCH_SISO_C)) {
1705                 /* switch in SISO */
1706                 tbl->action = IWL_MIMO3_SWITCH_SISO_A;
1707         }
1708         for (;;) {
1709                 lq_sta->action_counter++;
1710                 switch (tbl->action) {
1711                 case IWL_MIMO3_SWITCH_ANTENNA1:
1712                 case IWL_MIMO3_SWITCH_ANTENNA2:
1713                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle Antennas\n");
1714
1715                         if (tx_chains_num <= 3)
1716                                 break;
1717
1718                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1719                                 break;
1720
1721                         memcpy(search_tbl, tbl, sz);
1722                         if (rs_toggle_antenna(valid_tx_ant,
1723                                        &search_tbl->current_rate, search_tbl))
1724                                 goto out;
1725                         break;
1726                 case IWL_MIMO3_SWITCH_SISO_A:
1727                 case IWL_MIMO3_SWITCH_SISO_B:
1728                 case IWL_MIMO3_SWITCH_SISO_C:
1729                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to SISO\n");
1730
1731                         /* Set up new search table for SISO */
1732                         memcpy(search_tbl, tbl, sz);
1733
1734                         if (tbl->action == IWL_MIMO3_SWITCH_SISO_A)
1735                                 search_tbl->ant_type = ANT_A;
1736                         else if (tbl->action == IWL_MIMO3_SWITCH_SISO_B)
1737                                 search_tbl->ant_type = ANT_B;
1738                         else
1739                                 search_tbl->ant_type = ANT_C;
1740
1741                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1742                                 break;
1743
1744                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1745                                                  search_tbl, index);
1746                         if (!ret)
1747                                 goto out;
1748
1749                         break;
1750
1751                 case IWL_MIMO3_SWITCH_MIMO2_AB:
1752                 case IWL_MIMO3_SWITCH_MIMO2_AC:
1753                 case IWL_MIMO3_SWITCH_MIMO2_BC:
1754                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to MIMO2\n");
1755
1756                         memcpy(search_tbl, tbl, sz);
1757                         search_tbl->is_SGI = 0;
1758                         if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AB)
1759                                 search_tbl->ant_type = ANT_AB;
1760                         else if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AC)
1761                                 search_tbl->ant_type = ANT_AC;
1762                         else
1763                                 search_tbl->ant_type = ANT_BC;
1764
1765                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1766                                 break;
1767
1768                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1769                                                  search_tbl, index);
1770                         if (!ret)
1771                                 goto out;
1772
1773                         break;
1774
1775                 case IWL_MIMO3_SWITCH_GI:
1776                         if (!tbl->is_ht40 && !(ht_cap->cap &
1777                                                 IEEE80211_HT_CAP_SGI_20))
1778                                 break;
1779                         if (tbl->is_ht40 && !(ht_cap->cap &
1780                                                 IEEE80211_HT_CAP_SGI_40))
1781                                 break;
1782
1783                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle SGI/NGI\n");
1784
1785                         /* Set up new search table for MIMO */
1786                         memcpy(search_tbl, tbl, sz);
1787                         search_tbl->is_SGI = !tbl->is_SGI;
1788                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1789                         /*
1790                          * If active table already uses the fastest possible
1791                          * modulation (dual stream with short guard interval),
1792                          * and it's working well, there's no need to look
1793                          * for a better type of modulation!
1794                          */
1795                         if (tbl->is_SGI) {
1796                                 s32 tpt = lq_sta->last_tpt / 100;
1797                                 if (tpt >= search_tbl->expected_tpt[index])
1798                                         break;
1799                         }
1800                         search_tbl->current_rate =
1801                                 rate_n_flags_from_tbl(priv, search_tbl,
1802                                                       index, is_green);
1803                         update_search_tbl_counter = 1;
1804                         goto out;
1805                 }
1806                 tbl->action++;
1807                 if (tbl->action > IWL_MIMO3_SWITCH_GI)
1808                         tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1809
1810                 if (tbl->action == start_action)
1811                         break;
1812         }
1813         search_tbl->lq_type = LQ_NONE;
1814         return 0;
1815  out:
1816         lq_sta->search_better_tbl = 1;
1817         tbl->action++;
1818         if (tbl->action > IWL_MIMO3_SWITCH_GI)
1819                 tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1820         if (update_search_tbl_counter)
1821                 search_tbl->action = tbl->action;
1822
1823         return 0;
1824
1825 }
1826
1827 /*
1828  * Check whether we should continue using same modulation mode, or
1829  * begin search for a new mode, based on:
1830  * 1) # tx successes or failures while using this mode
1831  * 2) # times calling this function
1832  * 3) elapsed time in this mode (not used, for now)
1833  */
1834 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1835 {
1836         struct iwl_scale_tbl_info *tbl;
1837         int i;
1838         int active_tbl;
1839         int flush_interval_passed = 0;
1840         struct iwl_priv *priv;
1841
1842         priv = lq_sta->drv;
1843         active_tbl = lq_sta->active_tbl;
1844
1845         tbl = &(lq_sta->lq_info[active_tbl]);
1846
1847         /* If we've been disallowing search, see if we should now allow it */
1848         if (lq_sta->stay_in_tbl) {
1849
1850                 /* Elapsed time using current modulation mode */
1851                 if (lq_sta->flush_timer)
1852                         flush_interval_passed =
1853                         time_after(jiffies,
1854                                         (unsigned long)(lq_sta->flush_timer +
1855                                         IWL_RATE_SCALE_FLUSH_INTVL));
1856
1857                 /*
1858                  * Check if we should allow search for new modulation mode.
1859                  * If many frames have failed or succeeded, or we've used
1860                  * this same modulation for a long time, allow search, and
1861                  * reset history stats that keep track of whether we should
1862                  * allow a new search.  Also (below) reset all bitmaps and
1863                  * stats in active history.
1864                  */
1865                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1866                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1867                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1868                      && (flush_interval_passed))) {
1869                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1870                                      lq_sta->total_failed,
1871                                      lq_sta->total_success,
1872                                      flush_interval_passed);
1873
1874                         /* Allow search for new mode */
1875                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1876                         lq_sta->total_failed = 0;
1877                         lq_sta->total_success = 0;
1878                         lq_sta->flush_timer = 0;
1879
1880                 /*
1881                  * Else if we've used this modulation mode enough repetitions
1882                  * (regardless of elapsed time or success/failure), reset
1883                  * history bitmaps and rate-specific stats for all rates in
1884                  * active table.
1885                  */
1886                 } else {
1887                         lq_sta->table_count++;
1888                         if (lq_sta->table_count >=
1889                             lq_sta->table_count_limit) {
1890                                 lq_sta->table_count = 0;
1891
1892                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
1893                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1894                                         rs_rate_scale_clear_window(
1895                                                 &(tbl->win[i]));
1896                         }
1897                 }
1898
1899                 /* If transitioning to allow "search", reset all history
1900                  * bitmaps and stats in active table (this will become the new
1901                  * "search" table). */
1902                 if (!lq_sta->stay_in_tbl) {
1903                         for (i = 0; i < IWL_RATE_COUNT; i++)
1904                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1905                 }
1906         }
1907 }
1908
1909 /*
1910  * setup rate table in uCode
1911  * return rate_n_flags as used in the table
1912  */
1913 static u32 rs_update_rate_tbl(struct iwl_priv *priv,
1914                                 struct iwl_lq_sta *lq_sta,
1915                                 struct iwl_scale_tbl_info *tbl,
1916                                 int index, u8 is_green)
1917 {
1918         u32 rate;
1919
1920         /* Update uCode's rate table. */
1921         rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
1922         rs_fill_link_cmd(priv, lq_sta, rate);
1923         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC, false);
1924
1925         return rate;
1926 }
1927
1928 /*
1929  * Do rate scaling and search for new modulation mode.
1930  */
1931 static void rs_rate_scale_perform(struct iwl_priv *priv,
1932                                   struct sk_buff *skb,
1933                                   struct ieee80211_sta *sta,
1934                                   struct iwl_lq_sta *lq_sta)
1935 {
1936         struct ieee80211_hw *hw = priv->hw;
1937         struct ieee80211_conf *conf = &hw->conf;
1938         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1939         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1940         int low = IWL_RATE_INVALID;
1941         int high = IWL_RATE_INVALID;
1942         int index;
1943         int i;
1944         struct iwl_rate_scale_data *window = NULL;
1945         int current_tpt = IWL_INVALID_VALUE;
1946         int low_tpt = IWL_INVALID_VALUE;
1947         int high_tpt = IWL_INVALID_VALUE;
1948         u32 fail_count;
1949         s8 scale_action = 0;
1950         u16 rate_mask;
1951         u8 update_lq = 0;
1952         struct iwl_scale_tbl_info *tbl, *tbl1;
1953         u16 rate_scale_index_msk = 0;
1954         u32 rate;
1955         u8 is_green = 0;
1956         u8 active_tbl = 0;
1957         u8 done_search = 0;
1958         u16 high_low;
1959         s32 sr;
1960         u8 tid = MAX_TID_COUNT;
1961         struct iwl_tid_data *tid_data;
1962
1963         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
1964
1965         /* Send management frames and NO_ACK data using lowest rate. */
1966         /* TODO: this could probably be improved.. */
1967         if (!ieee80211_is_data(hdr->frame_control) ||
1968             info->flags & IEEE80211_TX_CTL_NO_ACK)
1969                 return;
1970
1971         if (!sta || !lq_sta)
1972                 return;
1973
1974         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1975
1976         tid = rs_tl_add_packet(lq_sta, hdr);
1977         if ((tid != MAX_TID_COUNT) && (lq_sta->tx_agg_tid_en & (1 << tid))) {
1978                 tid_data = &priv->stations[lq_sta->lq.sta_id].tid[tid];
1979                 if (tid_data->agg.state == IWL_AGG_OFF)
1980                         lq_sta->is_agg = 0;
1981                 else
1982                         lq_sta->is_agg = 1;
1983         } else
1984                 lq_sta->is_agg = 0;
1985
1986         /*
1987          * Select rate-scale / modulation-mode table to work with in
1988          * the rest of this function:  "search" if searching for better
1989          * modulation mode, or "active" if doing rate scaling within a mode.
1990          */
1991         if (!lq_sta->search_better_tbl)
1992                 active_tbl = lq_sta->active_tbl;
1993         else
1994                 active_tbl = 1 - lq_sta->active_tbl;
1995
1996         tbl = &(lq_sta->lq_info[active_tbl]);
1997         if (is_legacy(tbl->lq_type))
1998                 lq_sta->is_green = 0;
1999         else
2000                 lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2001         is_green = lq_sta->is_green;
2002
2003         /* current tx rate */
2004         index = lq_sta->last_txrate_idx;
2005
2006         IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
2007                        tbl->lq_type);
2008
2009         /* rates available for this association, and for modulation mode */
2010         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
2011
2012         IWL_DEBUG_RATE(priv, "mask 0x%04X \n", rate_mask);
2013
2014         /* mask with station rate restriction */
2015         if (is_legacy(tbl->lq_type)) {
2016                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
2017                         /* supp_rates has no CCK bits in A mode */
2018                         rate_scale_index_msk = (u16) (rate_mask &
2019                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
2020                 else
2021                         rate_scale_index_msk = (u16) (rate_mask &
2022                                                       lq_sta->supp_rates);
2023
2024         } else
2025                 rate_scale_index_msk = rate_mask;
2026
2027         if (!rate_scale_index_msk)
2028                 rate_scale_index_msk = rate_mask;
2029
2030         if (!((1 << index) & rate_scale_index_msk)) {
2031                 IWL_ERR(priv, "Current Rate is not valid\n");
2032                 if (lq_sta->search_better_tbl) {
2033                         /* revert to active table if search table is not valid*/
2034                         tbl->lq_type = LQ_NONE;
2035                         lq_sta->search_better_tbl = 0;
2036                         tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2037                         /* get "active" rate info */
2038                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2039                         rate = rs_update_rate_tbl(priv, lq_sta,
2040                                                   tbl, index, is_green);
2041                 }
2042                 return;
2043         }
2044
2045         /* Get expected throughput table and history window for current rate */
2046         if (!tbl->expected_tpt) {
2047                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
2048                 return;
2049         }
2050
2051         /* force user max rate if set by user */
2052         if ((lq_sta->max_rate_idx != -1) &&
2053             (lq_sta->max_rate_idx < index)) {
2054                 index = lq_sta->max_rate_idx;
2055                 update_lq = 1;
2056                 window = &(tbl->win[index]);
2057                 goto lq_update;
2058         }
2059
2060         window = &(tbl->win[index]);
2061
2062         /*
2063          * If there is not enough history to calculate actual average
2064          * throughput, keep analyzing results of more tx frames, without
2065          * changing rate or mode (bypass most of the rest of this function).
2066          * Set up new rate table in uCode only if old rate is not supported
2067          * in current association (use new rate found above).
2068          */
2069         fail_count = window->counter - window->success_counter;
2070         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
2071                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
2072                 IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
2073                                "for index %d\n",
2074                                window->success_counter, window->counter, index);
2075
2076                 /* Can't calculate this yet; not enough history */
2077                 window->average_tpt = IWL_INVALID_VALUE;
2078
2079                 /* Should we stay with this modulation mode,
2080                  * or search for a new one? */
2081                 rs_stay_in_table(lq_sta);
2082
2083                 goto out;
2084         }
2085         /* Else we have enough samples; calculate estimate of
2086          * actual average throughput */
2087
2088         /* Sanity-check TPT calculations */
2089         BUG_ON(window->average_tpt != ((window->success_ratio *
2090                         tbl->expected_tpt[index] + 64) / 128));
2091
2092         /* If we are searching for better modulation mode, check success. */
2093         if (lq_sta->search_better_tbl &&
2094             (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI)) {
2095                 /* If good success, continue using the "search" mode;
2096                  * no need to send new link quality command, since we're
2097                  * continuing to use the setup that we've been trying. */
2098                 if (window->average_tpt > lq_sta->last_tpt) {
2099
2100                         IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
2101                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2102                                         window->success_ratio,
2103                                         window->average_tpt,
2104                                         lq_sta->last_tpt);
2105
2106                         if (!is_legacy(tbl->lq_type))
2107                                 lq_sta->enable_counter = 1;
2108
2109                         /* Swap tables; "search" becomes "active" */
2110                         lq_sta->active_tbl = active_tbl;
2111                         current_tpt = window->average_tpt;
2112
2113                 /* Else poor success; go back to mode in "active" table */
2114                 } else {
2115
2116                         IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
2117                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2118                                         window->success_ratio,
2119                                         window->average_tpt,
2120                                         lq_sta->last_tpt);
2121
2122                         /* Nullify "search" table */
2123                         tbl->lq_type = LQ_NONE;
2124
2125                         /* Revert to "active" table */
2126                         active_tbl = lq_sta->active_tbl;
2127                         tbl = &(lq_sta->lq_info[active_tbl]);
2128
2129                         /* Revert to "active" rate and throughput info */
2130                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2131                         current_tpt = lq_sta->last_tpt;
2132
2133                         /* Need to set up a new rate table in uCode */
2134                         update_lq = 1;
2135                 }
2136
2137                 /* Either way, we've made a decision; modulation mode
2138                  * search is done, allow rate adjustment next time. */
2139                 lq_sta->search_better_tbl = 0;
2140                 done_search = 1;        /* Don't switch modes below! */
2141                 goto lq_update;
2142         }
2143
2144         /* (Else) not in search of better modulation mode, try for better
2145          * starting rate, while staying in this mode. */
2146         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
2147                                         tbl->lq_type);
2148         low = high_low & 0xff;
2149         high = (high_low >> 8) & 0xff;
2150
2151         /* If user set max rate, dont allow higher than user constrain */
2152         if ((lq_sta->max_rate_idx != -1) &&
2153             (lq_sta->max_rate_idx < high))
2154                 high = IWL_RATE_INVALID;
2155
2156         sr = window->success_ratio;
2157
2158         /* Collect measured throughputs for current and adjacent rates */
2159         current_tpt = window->average_tpt;
2160         if (low != IWL_RATE_INVALID)
2161                 low_tpt = tbl->win[low].average_tpt;
2162         if (high != IWL_RATE_INVALID)
2163                 high_tpt = tbl->win[high].average_tpt;
2164
2165         scale_action = 0;
2166
2167         /* Too many failures, decrease rate */
2168         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
2169                 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
2170                 scale_action = -1;
2171
2172         /* No throughput measured yet for adjacent rates; try increase. */
2173         } else if ((low_tpt == IWL_INVALID_VALUE) &&
2174                    (high_tpt == IWL_INVALID_VALUE)) {
2175
2176                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
2177                         scale_action = 1;
2178                 else if (low != IWL_RATE_INVALID)
2179                         scale_action = 0;
2180         }
2181
2182         /* Both adjacent throughputs are measured, but neither one has better
2183          * throughput; we're using the best rate, don't change it! */
2184         else if ((low_tpt != IWL_INVALID_VALUE) &&
2185                  (high_tpt != IWL_INVALID_VALUE) &&
2186                  (low_tpt < current_tpt) &&
2187                  (high_tpt < current_tpt))
2188                 scale_action = 0;
2189
2190         /* At least one adjacent rate's throughput is measured,
2191          * and may have better performance. */
2192         else {
2193                 /* Higher adjacent rate's throughput is measured */
2194                 if (high_tpt != IWL_INVALID_VALUE) {
2195                         /* Higher rate has better throughput */
2196                         if (high_tpt > current_tpt &&
2197                                         sr >= IWL_RATE_INCREASE_TH) {
2198                                 scale_action = 1;
2199                         } else {
2200                                 scale_action = 0;
2201                         }
2202
2203                 /* Lower adjacent rate's throughput is measured */
2204                 } else if (low_tpt != IWL_INVALID_VALUE) {
2205                         /* Lower rate has better throughput */
2206                         if (low_tpt > current_tpt) {
2207                                 IWL_DEBUG_RATE(priv,
2208                                     "decrease rate because of low tpt\n");
2209                                 scale_action = -1;
2210                         } else if (sr >= IWL_RATE_INCREASE_TH) {
2211                                 scale_action = 1;
2212                         }
2213                 }
2214         }
2215
2216         /* Sanity check; asked for decrease, but success rate or throughput
2217          * has been good at old rate.  Don't change it. */
2218         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
2219                     ((sr > IWL_RATE_HIGH_TH) ||
2220                      (current_tpt > (100 * tbl->expected_tpt[low]))))
2221                 scale_action = 0;
2222         if (!iwl_ht_enabled(priv) && !is_legacy(tbl->lq_type))
2223                 scale_action = -1;
2224         if (iwl_tx_ant_restriction(priv) != IWL_ANT_OK_MULTI &&
2225                 (is_mimo2(tbl->lq_type) || is_mimo3(tbl->lq_type)))
2226                 scale_action = -1;
2227         switch (scale_action) {
2228         case -1:
2229                 /* Decrease starting rate, update uCode's rate table */
2230                 if (low != IWL_RATE_INVALID) {
2231                         update_lq = 1;
2232                         index = low;
2233                 }
2234
2235                 break;
2236         case 1:
2237                 /* Increase starting rate, update uCode's rate table */
2238                 if (high != IWL_RATE_INVALID) {
2239                         update_lq = 1;
2240                         index = high;
2241                 }
2242
2243                 break;
2244         case 0:
2245                 /* No change */
2246         default:
2247                 break;
2248         }
2249
2250         IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
2251                     "high %d type %d\n",
2252                      index, scale_action, low, high, tbl->lq_type);
2253
2254 lq_update:
2255         /* Replace uCode's rate table for the destination station. */
2256         if (update_lq)
2257                 rate = rs_update_rate_tbl(priv, lq_sta,
2258                                           tbl, index, is_green);
2259
2260         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI) {
2261                 /* Should we stay with this modulation mode,
2262                  * or search for a new one? */
2263                 rs_stay_in_table(lq_sta);
2264         }
2265         /*
2266          * Search for new modulation mode if we're:
2267          * 1)  Not changing rates right now
2268          * 2)  Not just finishing up a search
2269          * 3)  Allowing a new search
2270          */
2271         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
2272                 /* Save current throughput to compare with "search" throughput*/
2273                 lq_sta->last_tpt = current_tpt;
2274
2275                 /* Select a new "search" modulation mode to try.
2276                  * If one is found, set up the new "search" table. */
2277                 if (is_legacy(tbl->lq_type))
2278                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
2279                 else if (is_siso(tbl->lq_type))
2280                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2281                 else if (is_mimo2(tbl->lq_type))
2282                         rs_move_mimo2_to_other(priv, lq_sta, conf, sta, index);
2283                 else
2284                         rs_move_mimo3_to_other(priv, lq_sta, conf, sta, index);
2285
2286                 /* If new "search" mode was selected, set up in uCode table */
2287                 if (lq_sta->search_better_tbl) {
2288                         /* Access the "search" table, clear its history. */
2289                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2290                         for (i = 0; i < IWL_RATE_COUNT; i++)
2291                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2292
2293                         /* Use new "search" start rate */
2294                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2295
2296                         IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
2297                                      tbl->current_rate, index);
2298                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
2299                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC, false);
2300                 } else
2301                         done_search = 1;
2302         }
2303
2304         if (done_search && !lq_sta->stay_in_tbl) {
2305                 /* If the "active" (non-search) mode was legacy,
2306                  * and we've tried switching antennas,
2307                  * but we haven't been able to try HT modes (not available),
2308                  * stay with best antenna legacy modulation for a while
2309                  * before next round of mode comparisons. */
2310                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2311                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2312                     lq_sta->action_counter > tbl1->max_search) {
2313                         IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2314                         rs_set_stay_in_table(priv, 1, lq_sta);
2315                 }
2316
2317                 /* If we're in an HT mode, and all 3 mode switch actions
2318                  * have been tried and compared, stay in this best modulation
2319                  * mode for a while before next round of mode comparisons. */
2320                 if (lq_sta->enable_counter &&
2321                     (lq_sta->action_counter >= tbl1->max_search) &&
2322                     iwl_ht_enabled(priv)) {
2323                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2324                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2325                             (tid != MAX_TID_COUNT)) {
2326                                 tid_data =
2327                                    &priv->stations[lq_sta->lq.sta_id].tid[tid];
2328                                 if (tid_data->agg.state == IWL_AGG_OFF) {
2329                                         IWL_DEBUG_RATE(priv,
2330                                                        "try to aggregate tid %d\n",
2331                                                        tid);
2332                                         rs_tl_turn_on_agg(priv, tid,
2333                                                           lq_sta, sta);
2334                                 }
2335                         }
2336                         rs_set_stay_in_table(priv, 0, lq_sta);
2337                 }
2338         }
2339
2340 out:
2341         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2342         i = index;
2343         lq_sta->last_txrate_idx = i;
2344
2345         return;
2346 }
2347
2348 /**
2349  * rs_initialize_lq - Initialize a station's hardware rate table
2350  *
2351  * The uCode's station table contains a table of fallback rates
2352  * for automatic fallback during transmission.
2353  *
2354  * NOTE: This sets up a default set of values.  These will be replaced later
2355  *       if the driver's iwl-agn-rs rate scaling algorithm is used, instead of
2356  *       rc80211_simple.
2357  *
2358  * NOTE: Run REPLY_ADD_STA command to set up station table entry, before
2359  *       calling this function (which runs REPLY_TX_LINK_QUALITY_CMD,
2360  *       which requires station table entry to exist).
2361  */
2362 static void rs_initialize_lq(struct iwl_priv *priv,
2363                              struct ieee80211_conf *conf,
2364                              struct ieee80211_sta *sta,
2365                              struct iwl_lq_sta *lq_sta)
2366 {
2367         struct iwl_scale_tbl_info *tbl;
2368         int rate_idx;
2369         int i;
2370         u32 rate;
2371         u8 use_green = rs_use_green(sta, &priv->current_ht_config);
2372         u8 active_tbl = 0;
2373         u8 valid_tx_ant;
2374
2375         if (!sta || !lq_sta)
2376                 goto out;
2377
2378         i = lq_sta->last_txrate_idx;
2379
2380         if ((lq_sta->lq.sta_id == 0xff) &&
2381             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2382                 goto out;
2383
2384         valid_tx_ant = priv->hw_params.valid_tx_ant;
2385
2386         if (!lq_sta->search_better_tbl)
2387                 active_tbl = lq_sta->active_tbl;
2388         else
2389                 active_tbl = 1 - lq_sta->active_tbl;
2390
2391         tbl = &(lq_sta->lq_info[active_tbl]);
2392
2393         if ((i < 0) || (i >= IWL_RATE_COUNT))
2394                 i = 0;
2395
2396         rate = iwl_rates[i].plcp;
2397         tbl->ant_type = first_antenna(valid_tx_ant);
2398         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2399
2400         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2401                 rate |= RATE_MCS_CCK_MSK;
2402
2403         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2404         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2405             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2406
2407         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2408         tbl->current_rate = rate;
2409         rs_set_expected_tpt_table(lq_sta, tbl);
2410         rs_fill_link_cmd(NULL, lq_sta, rate);
2411         priv->stations[lq_sta->lq.sta_id].lq = &lq_sta->lq;
2412         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_SYNC, true);
2413  out:
2414         return;
2415 }
2416
2417 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2418                         struct ieee80211_tx_rate_control *txrc)
2419 {
2420
2421         struct sk_buff *skb = txrc->skb;
2422         struct ieee80211_supported_band *sband = txrc->sband;
2423         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2424         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2425         struct iwl_lq_sta *lq_sta = priv_sta;
2426         int rate_idx;
2427
2428         IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2429
2430         /* Get max rate if user set max rate */
2431         if (lq_sta) {
2432                 lq_sta->max_rate_idx = txrc->max_rate_idx;
2433                 if ((sband->band == IEEE80211_BAND_5GHZ) &&
2434                     (lq_sta->max_rate_idx != -1))
2435                         lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2436                 if ((lq_sta->max_rate_idx < 0) ||
2437                     (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2438                         lq_sta->max_rate_idx = -1;
2439         }
2440
2441         /* Treat uninitialized rate scaling data same as non-existing. */
2442         if (lq_sta && !lq_sta->drv) {
2443                 IWL_DEBUG_RATE(priv, "Rate scaling not initialized yet.\n");
2444                 priv_sta = NULL;
2445         }
2446
2447         /* Send management frames and NO_ACK data using lowest rate. */
2448         if (rate_control_send_low(sta, priv_sta, txrc))
2449                 return;
2450
2451         rate_idx  = lq_sta->last_txrate_idx;
2452
2453         if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2454                 rate_idx -= IWL_FIRST_OFDM_RATE;
2455                 /* 6M and 9M shared same MCS index */
2456                 rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2457                 if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2458                     IWL_RATE_MIMO3_6M_PLCP)
2459                         rate_idx = rate_idx + (2 * MCS_INDEX_PER_STREAM);
2460                 else if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2461                          IWL_RATE_MIMO2_6M_PLCP)
2462                         rate_idx = rate_idx + MCS_INDEX_PER_STREAM;
2463                 info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2464                 if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2465                         info->control.rates[0].flags |= IEEE80211_TX_RC_SHORT_GI;
2466                 if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2467                         info->control.rates[0].flags |= IEEE80211_TX_RC_DUP_DATA;
2468                 if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2469                         info->control.rates[0].flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
2470                 if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2471                         info->control.rates[0].flags |= IEEE80211_TX_RC_GREEN_FIELD;
2472         } else {
2473                 /* Check for invalid rates */
2474                 if ((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT_LEGACY) ||
2475                                 ((sband->band == IEEE80211_BAND_5GHZ) &&
2476                                  (rate_idx < IWL_FIRST_OFDM_RATE)))
2477                         rate_idx = rate_lowest_index(sband, sta);
2478                 /* On valid 5 GHz rate, adjust index */
2479                 else if (sband->band == IEEE80211_BAND_5GHZ)
2480                         rate_idx -= IWL_FIRST_OFDM_RATE;
2481                 info->control.rates[0].flags = 0;
2482         }
2483         info->control.rates[0].idx = rate_idx;
2484
2485 }
2486
2487 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2488                           gfp_t gfp)
2489 {
2490         struct iwl_lq_sta *lq_sta;
2491         struct iwl_station_priv *sta_priv = (struct iwl_station_priv *) sta->drv_priv;
2492         struct iwl_priv *priv;
2493
2494         priv = (struct iwl_priv *)priv_rate;
2495         IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2496
2497         lq_sta = &sta_priv->lq_sta;
2498
2499         return lq_sta;
2500 }
2501
2502 /*
2503  * Called after adding a new station to initialize rate scaling
2504  */
2505 void iwl_rs_rate_init(struct iwl_priv *priv, struct ieee80211_sta *sta, u8 sta_id)
2506 {
2507         int i, j;
2508         struct ieee80211_hw *hw = priv->hw;
2509         struct ieee80211_conf *conf = &priv->hw->conf;
2510         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2511         struct iwl_station_priv *sta_priv;
2512         struct iwl_lq_sta *lq_sta;
2513         struct ieee80211_supported_band *sband;
2514
2515         sta_priv = (struct iwl_station_priv *) sta->drv_priv;
2516         lq_sta = &sta_priv->lq_sta;
2517         sband = hw->wiphy->bands[conf->channel->band];
2518
2519
2520         lq_sta->lq.sta_id = sta_id;
2521
2522         for (j = 0; j < LQ_SIZE; j++)
2523                 for (i = 0; i < IWL_RATE_COUNT; i++)
2524                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2525
2526         lq_sta->flush_timer = 0;
2527         lq_sta->supp_rates = sta->supp_rates[sband->band];
2528         for (j = 0; j < LQ_SIZE; j++)
2529                 for (i = 0; i < IWL_RATE_COUNT; i++)
2530                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2531
2532         IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init for station %d ***\n",
2533                        sta_id);
2534         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2535          * the lowest or the highest rate.. Could consider using RSSI from
2536          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2537          * after assoc.. */
2538
2539         lq_sta->is_dup = 0;
2540         lq_sta->max_rate_idx = -1;
2541         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2542         lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2543         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2544         lq_sta->band = priv->band;
2545         /*
2546          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2547          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2548          */
2549         lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
2550         lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
2551         lq_sta->active_siso_rate &= ~((u16)0x2);
2552         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2553
2554         /* Same here */
2555         lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
2556         lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
2557         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2558         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2559
2560         lq_sta->active_mimo3_rate = ht_cap->mcs.rx_mask[2] << 1;
2561         lq_sta->active_mimo3_rate |= ht_cap->mcs.rx_mask[2] & 0x1;
2562         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2563         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2564
2565         IWL_DEBUG_RATE(priv, "SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2566                      lq_sta->active_siso_rate,
2567                      lq_sta->active_mimo2_rate,
2568                      lq_sta->active_mimo3_rate);
2569
2570         /* These values will be overridden later */
2571         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2572         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2573
2574         /* as default allow aggregation for all tids */
2575         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2576         lq_sta->drv = priv;
2577
2578         /* Set last_txrate_idx to lowest rate */
2579         lq_sta->last_txrate_idx = rate_lowest_index(sband, sta);
2580         if (sband->band == IEEE80211_BAND_5GHZ)
2581                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2582         lq_sta->is_agg = 0;
2583
2584         rs_initialize_lq(priv, conf, sta, lq_sta);
2585 }
2586
2587 static void rs_fill_link_cmd(struct iwl_priv *priv,
2588                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2589 {
2590         struct iwl_scale_tbl_info tbl_type;
2591         int index = 0;
2592         int rate_idx;
2593         int repeat_rate = 0;
2594         u8 ant_toggle_cnt = 0;
2595         u8 use_ht_possible = 1;
2596         u8 valid_tx_ant = 0;
2597         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2598
2599         /* Override starting rate (index 0) if needed for debug purposes */
2600         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2601
2602         /* Interpret new_rate (rate_n_flags) */
2603         memset(&tbl_type, 0, sizeof(tbl_type));
2604         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2605                                   &tbl_type, &rate_idx);
2606
2607         /* How many times should we repeat the initial rate? */
2608         if (is_legacy(tbl_type.lq_type)) {
2609                 ant_toggle_cnt = 1;
2610                 repeat_rate = IWL_NUMBER_TRY;
2611         } else {
2612                 repeat_rate = IWL_HT_NUMBER_TRY;
2613         }
2614
2615         lq_cmd->general_params.mimo_delimiter =
2616                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2617
2618         /* Fill 1st table entry (index 0) */
2619         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2620
2621         if (num_of_ant(tbl_type.ant_type) == 1) {
2622                 lq_cmd->general_params.single_stream_ant_msk =
2623                                                 tbl_type.ant_type;
2624         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2625                 lq_cmd->general_params.dual_stream_ant_msk =
2626                                                 tbl_type.ant_type;
2627         } /* otherwise we don't modify the existing value */
2628
2629         index++;
2630         repeat_rate--;
2631
2632         if (priv)
2633                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2634
2635         /* Fill rest of rate table */
2636         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2637                 /* Repeat initial/next rate.
2638                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2639                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2640                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2641                         if (is_legacy(tbl_type.lq_type)) {
2642                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2643                                         ant_toggle_cnt++;
2644                                 else if (priv &&
2645                                          rs_toggle_antenna(valid_tx_ant,
2646                                                         &new_rate, &tbl_type))
2647                                         ant_toggle_cnt = 1;
2648 }
2649
2650                         /* Override next rate if needed for debug purposes */
2651                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2652
2653                         /* Fill next table entry */
2654                         lq_cmd->rs_table[index].rate_n_flags =
2655                                         cpu_to_le32(new_rate);
2656                         repeat_rate--;
2657                         index++;
2658                 }
2659
2660                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2661                                                 &rate_idx);
2662
2663                 /* Indicate to uCode which entries might be MIMO.
2664                  * If initial rate was MIMO, this will finally end up
2665                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2666                 if (is_mimo(tbl_type.lq_type))
2667                         lq_cmd->general_params.mimo_delimiter = index;
2668
2669                 /* Get next rate */
2670                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2671                                              use_ht_possible);
2672
2673                 /* How many times should we repeat the next rate? */
2674                 if (is_legacy(tbl_type.lq_type)) {
2675                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2676                                 ant_toggle_cnt++;
2677                         else if (priv &&
2678                                  rs_toggle_antenna(valid_tx_ant,
2679                                                    &new_rate, &tbl_type))
2680                                 ant_toggle_cnt = 1;
2681
2682                         repeat_rate = IWL_NUMBER_TRY;
2683                 } else {
2684                         repeat_rate = IWL_HT_NUMBER_TRY;
2685                 }
2686
2687                 /* Don't allow HT rates after next pass.
2688                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2689                 use_ht_possible = 0;
2690
2691                 /* Override next rate if needed for debug purposes */
2692                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2693
2694                 /* Fill next table entry */
2695                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2696
2697                 index++;
2698                 repeat_rate--;
2699         }
2700
2701         lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
2702         lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2703         lq_cmd->agg_params.agg_time_limit =
2704                 cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2705 }
2706
2707 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2708 {
2709         return hw->priv;
2710 }
2711 /* rate scale requires free function to be implemented */
2712 static void rs_free(void *priv_rate)
2713 {
2714         return;
2715 }
2716
2717 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2718                         void *priv_sta)
2719 {
2720         struct iwl_priv *priv __maybe_unused = priv_r;
2721
2722         IWL_DEBUG_RATE(priv, "enter\n");
2723         IWL_DEBUG_RATE(priv, "leave\n");
2724 }
2725
2726
2727 #ifdef CONFIG_MAC80211_DEBUGFS
2728 static int open_file_generic(struct inode *inode, struct file *file)
2729 {
2730         file->private_data = inode->i_private;
2731         return 0;
2732 }
2733 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2734                              u32 *rate_n_flags, int index)
2735 {
2736         struct iwl_priv *priv;
2737         u8 valid_tx_ant;
2738         u8 ant_sel_tx;
2739
2740         priv = lq_sta->drv;
2741         valid_tx_ant = priv->hw_params.valid_tx_ant;
2742         if (lq_sta->dbg_fixed_rate) {
2743                 ant_sel_tx =
2744                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2745                   >> RATE_MCS_ANT_POS);
2746                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2747                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2748                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2749                 } else {
2750                         lq_sta->dbg_fixed_rate = 0;
2751                         IWL_ERR(priv,
2752                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2753                             ant_sel_tx, valid_tx_ant);
2754                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2755                 }
2756         } else {
2757                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2758         }
2759 }
2760
2761 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2762                         const char __user *user_buf, size_t count, loff_t *ppos)
2763 {
2764         struct iwl_lq_sta *lq_sta = file->private_data;
2765         struct iwl_priv *priv;
2766         char buf[64];
2767         int buf_size;
2768         u32 parsed_rate;
2769
2770         priv = lq_sta->drv;
2771         memset(buf, 0, sizeof(buf));
2772         buf_size = min(count, sizeof(buf) -  1);
2773         if (copy_from_user(buf, user_buf, buf_size))
2774                 return -EFAULT;
2775
2776         if (sscanf(buf, "%x", &parsed_rate) == 1)
2777                 lq_sta->dbg_fixed_rate = parsed_rate;
2778         else
2779                 lq_sta->dbg_fixed_rate = 0;
2780
2781         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2782         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2783         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2784         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2785
2786         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2787                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2788
2789         if (lq_sta->dbg_fixed_rate) {
2790                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2791                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC, false);
2792         }
2793
2794         return count;
2795 }
2796
2797 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2798                         char __user *user_buf, size_t count, loff_t *ppos)
2799 {
2800         char *buff;
2801         int desc = 0;
2802         int i = 0;
2803         int index = 0;
2804         ssize_t ret;
2805
2806         struct iwl_lq_sta *lq_sta = file->private_data;
2807         struct iwl_priv *priv;
2808         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2809
2810         priv = lq_sta->drv;
2811         buff = kmalloc(1024, GFP_KERNEL);
2812         if (!buff)
2813                 return -ENOMEM;
2814
2815         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2816         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2817                         lq_sta->total_failed, lq_sta->total_success,
2818                         lq_sta->active_legacy_rate);
2819         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2820                         lq_sta->dbg_fixed_rate);
2821         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2822             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2823             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2824             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2825         desc += sprintf(buff+desc, "lq type %s\n",
2826            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2827         if (is_Ht(tbl->lq_type)) {
2828                 desc += sprintf(buff+desc, " %s",
2829                    (is_siso(tbl->lq_type)) ? "SISO" :
2830                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2831                    desc += sprintf(buff+desc, " %s",
2832                    (tbl->is_ht40) ? "40MHz" : "20MHz");
2833                    desc += sprintf(buff+desc, " %s %s %s\n", (tbl->is_SGI) ? "SGI" : "",
2834                    (lq_sta->is_green) ? "GF enabled" : "",
2835                    (lq_sta->is_agg) ? "AGG on" : "");
2836         }
2837         desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2838                 lq_sta->last_rate_n_flags);
2839         desc += sprintf(buff+desc, "general:"
2840                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2841                 lq_sta->lq.general_params.flags,
2842                 lq_sta->lq.general_params.mimo_delimiter,
2843                 lq_sta->lq.general_params.single_stream_ant_msk,
2844                 lq_sta->lq.general_params.dual_stream_ant_msk);
2845
2846         desc += sprintf(buff+desc, "agg:"
2847                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2848                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2849                         lq_sta->lq.agg_params.agg_dis_start_th,
2850                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2851
2852         desc += sprintf(buff+desc,
2853                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2854                         lq_sta->lq.general_params.start_rate_index[0],
2855                         lq_sta->lq.general_params.start_rate_index[1],
2856                         lq_sta->lq.general_params.start_rate_index[2],
2857                         lq_sta->lq.general_params.start_rate_index[3]);
2858
2859         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2860                 index = iwl_hwrate_to_plcp_idx(
2861                         le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2862                 if (is_legacy(tbl->lq_type)) {
2863                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2864                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2865                                 iwl_rate_mcs[index].mbps);
2866                 } else {
2867                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps (%s)\n",
2868                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2869                                 iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
2870                 }
2871         }
2872
2873         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2874         kfree(buff);
2875         return ret;
2876 }
2877
2878 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2879         .write = rs_sta_dbgfs_scale_table_write,
2880         .read = rs_sta_dbgfs_scale_table_read,
2881         .open = open_file_generic,
2882 };
2883 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2884                         char __user *user_buf, size_t count, loff_t *ppos)
2885 {
2886         char *buff;
2887         int desc = 0;
2888         int i, j;
2889         ssize_t ret;
2890
2891         struct iwl_lq_sta *lq_sta = file->private_data;
2892
2893         buff = kmalloc(1024, GFP_KERNEL);
2894         if (!buff)
2895                 return -ENOMEM;
2896
2897         for (i = 0; i < LQ_SIZE; i++) {
2898                 desc += sprintf(buff+desc,
2899                                 "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
2900                                 "rate=0x%X\n",
2901                                 lq_sta->active_tbl == i ? "*" : "x",
2902                                 lq_sta->lq_info[i].lq_type,
2903                                 lq_sta->lq_info[i].is_SGI,
2904                                 lq_sta->lq_info[i].is_ht40,
2905                                 lq_sta->lq_info[i].is_dup,
2906                                 lq_sta->is_green,
2907                                 lq_sta->lq_info[i].current_rate);
2908                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2909                         desc += sprintf(buff+desc,
2910                                 "counter=%d success=%d %%=%d\n",
2911                                 lq_sta->lq_info[i].win[j].counter,
2912                                 lq_sta->lq_info[i].win[j].success_counter,
2913                                 lq_sta->lq_info[i].win[j].success_ratio);
2914                 }
2915         }
2916         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2917         kfree(buff);
2918         return ret;
2919 }
2920
2921 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2922         .read = rs_sta_dbgfs_stats_table_read,
2923         .open = open_file_generic,
2924 };
2925
2926 static ssize_t rs_sta_dbgfs_rate_scale_data_read(struct file *file,
2927                         char __user *user_buf, size_t count, loff_t *ppos)
2928 {
2929         char buff[120];
2930         int desc = 0;
2931         ssize_t ret;
2932
2933         struct iwl_lq_sta *lq_sta = file->private_data;
2934         struct iwl_priv *priv;
2935         struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
2936
2937         priv = lq_sta->drv;
2938
2939         if (is_Ht(tbl->lq_type))
2940                 desc += sprintf(buff+desc,
2941                                 "Bit Rate= %d Mb/s\n",
2942                                 tbl->expected_tpt[lq_sta->last_txrate_idx]);
2943         else
2944                 desc += sprintf(buff+desc,
2945                                 "Bit Rate= %d Mb/s\n",
2946                                 iwl_rates[lq_sta->last_txrate_idx].ieee >> 1);
2947         desc += sprintf(buff+desc, "Noise Level= %d dBm\n",
2948                         priv->last_rx_noise);
2949
2950         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2951         return ret;
2952 }
2953
2954 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
2955         .read = rs_sta_dbgfs_rate_scale_data_read,
2956         .open = open_file_generic,
2957 };
2958
2959 static void rs_add_debugfs(void *priv, void *priv_sta,
2960                                         struct dentry *dir)
2961 {
2962         struct iwl_lq_sta *lq_sta = priv_sta;
2963         lq_sta->rs_sta_dbgfs_scale_table_file =
2964                 debugfs_create_file("rate_scale_table", S_IRUSR | S_IWUSR, dir,
2965                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2966         lq_sta->rs_sta_dbgfs_stats_table_file =
2967                 debugfs_create_file("rate_stats_table", S_IRUSR, dir,
2968                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2969         lq_sta->rs_sta_dbgfs_rate_scale_data_file =
2970                 debugfs_create_file("rate_scale_data", S_IRUSR, dir,
2971                         lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
2972         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2973                 debugfs_create_u8("tx_agg_tid_enable", S_IRUSR | S_IWUSR, dir,
2974                 &lq_sta->tx_agg_tid_en);
2975
2976 }
2977
2978 static void rs_remove_debugfs(void *priv, void *priv_sta)
2979 {
2980         struct iwl_lq_sta *lq_sta = priv_sta;
2981         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2982         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2983         debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
2984         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2985 }
2986 #endif
2987
2988 /*
2989  * Initialization of rate scaling information is done by driver after
2990  * the station is added. Since mac80211 calls this function before a
2991  * station is added we ignore it.
2992  */
2993 static void rs_rate_init_stub(void *priv_r, struct ieee80211_supported_band *sband,
2994                          struct ieee80211_sta *sta, void *priv_sta)
2995 {
2996 }
2997 static struct rate_control_ops rs_ops = {
2998         .module = NULL,
2999         .name = RS_NAME,
3000         .tx_status = rs_tx_status,
3001         .get_rate = rs_get_rate,
3002         .rate_init = rs_rate_init_stub,
3003         .alloc = rs_alloc,
3004         .free = rs_free,
3005         .alloc_sta = rs_alloc_sta,
3006         .free_sta = rs_free_sta,
3007 #ifdef CONFIG_MAC80211_DEBUGFS
3008         .add_sta_debugfs = rs_add_debugfs,
3009         .remove_sta_debugfs = rs_remove_debugfs,
3010 #endif
3011 };
3012
3013 int iwlagn_rate_control_register(void)
3014 {
3015         return ieee80211_rate_control_register(&rs_ops);
3016 }
3017
3018 void iwlagn_rate_control_unregister(void)
3019 {
3020         ieee80211_rate_control_unregister(&rs_ops);
3021 }
3022