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

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2005 - 2009 Intel Corporation. All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  * Contact Information:
  22  *  Intel Linux Wireless <ilw@linux.intel.com>
  23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  24  *
  25  *****************************************************************************/
  26 #include <linux/kernel.h>
  27 #include <linux/init.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/wireless.h>
  30 #include <net/mac80211.h>
  31
  32 #include <linux/netdevice.h>
  33 #include <linux/etherdevice.h>
  34 #include <linux/delay.h>
  35
  36 #include <linux/workqueue.h>
  37
  38 #include "iwl-dev.h"
  39 #include "iwl-sta.h"
  40 #include "iwl-core.h"
  41
  42 #define RS_NAME "iwl-agn-rs"
  43
  44 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
  45 #define IWL_NUMBER_TRY      1
  46 #define IWL_HT_NUMBER_TRY   3
  47
  48 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
  49 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
  50 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
  51
  52 /* max allowed rate miss before sync LQ cmd */
  53 #define IWL_MISSED_RATE_MAX             15
  54 /* max time to accum history 2 seconds */
  55 #define IWL_RATE_SCALE_FLUSH_INTVL   (3*HZ)
  56
  57 static u8 rs_ht_to_legacy[] = {
  58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  60         IWL_RATE_6M_INDEX,
  61         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
  62         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
  63         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
  64         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
  65 };
  66
  67 static const u8 ant_toggle_lookup[] = {
  68         /*ANT_NONE -> */ ANT_NONE,
  69         /*ANT_A    -> */ ANT_B,
  70         /*ANT_B    -> */ ANT_C,
  71         /*ANT_AB   -> */ ANT_BC,
  72         /*ANT_C    -> */ ANT_A,
  73         /*ANT_AC   -> */ ANT_AB,
  74         /*ANT_BC   -> */ ANT_AC,
  75         /*ANT_ABC  -> */ ANT_ABC,
  76 };
  77
  78 /**
  79  * struct iwl_rate_scale_data -- tx success history for one rate
  80  */
  81 struct iwl_rate_scale_data {
  82         u64 data;               /* bitmap of successful frames */
  83         s32 success_counter;    /* number of frames successful */
  84         s32 success_ratio;      /* per-cent * 128  */
  85         s32 counter;            /* number of frames attempted */
  86         s32 average_tpt;        /* success ratio * expected throughput */
  87         unsigned long stamp;
  88 };
  89
  90 /**
  91  * struct iwl_scale_tbl_info -- tx params and success history for all rates
  92  *
  93  * There are two of these in struct iwl_lq_sta,
  94  * one for "active", and one for "search".
  95  */
  96 struct iwl_scale_tbl_info {
  97         enum iwl_table_type lq_type;
  98         u8 ant_type;
  99         u8 is_SGI;      /* 1 = short guard interval */
 100         u8 is_ht40;     /* 1 = 40 MHz channel width */
 101         u8 is_dup;      /* 1 = duplicated data streams */
 102         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
 103         u8 max_search;  /* maximun number of tables we can search */
 104         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
 105         u32 current_rate;  /* rate_n_flags, uCode API format */
 106         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
 107 };
 108
 109 struct iwl_traffic_load {
 110         unsigned long time_stamp;       /* age of the oldest statistics */
 111         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
 112                                                  * slice */
 113         u32 total;                      /* total num of packets during the
 114                                          * last TID_MAX_TIME_DIFF */
 115         u8 queue_count;                 /* number of queues that has
 116                                          * been used since the last cleanup */
 117         u8 head;                        /* start of the circular buffer */
 118 };
 119
 120 /**
 121  * struct iwl_lq_sta -- driver's rate scaling private structure
 122  *
 123  * Pointer to this gets passed back and forth between driver and mac80211.
 124  */
 125 struct iwl_lq_sta {
 126         u8 active_tbl;          /* index of active table, range 0-1 */
 127         u8 enable_counter;      /* indicates HT mode */
 128         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
 129         u8 search_better_tbl;   /* 1: currently trying alternate mode */
 130         s32 last_tpt;
 131
 132         /* The following determine when to search for a new mode */
 133         u32 table_count_limit;
 134         u32 max_failure_limit;  /* # failed frames before new search */
 135         u32 max_success_limit;  /* # successful frames before new search */
 136         u32 table_count;
 137         u32 total_failed;       /* total failed frames, any/all rates */
 138         u32 total_success;      /* total successful frames, any/all rates */
 139         u64 flush_timer;        /* time staying in mode before new search */
 140
 141         u8 action_counter;      /* # mode-switch actions tried */
 142         u8 is_green;
 143         u8 is_dup;
 144         enum ieee80211_band band;
 145         u8 ibss_sta_added;
 146
 147         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
 148         u32 supp_rates;
 149         u16 active_legacy_rate;
 150         u16 active_siso_rate;
 151         u16 active_mimo2_rate;
 152         u16 active_mimo3_rate;
 153         u16 active_rate_basic;
 154         s8 max_rate_idx;     /* Max rate set by user */
 155         u8 missed_rate_counter;
 156
 157         struct iwl_link_quality_cmd lq;
 158         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
 159         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
 160         u8 tx_agg_tid_en;
 161 #ifdef CONFIG_MAC80211_DEBUGFS
 162         struct dentry *rs_sta_dbgfs_scale_table_file;
 163         struct dentry *rs_sta_dbgfs_stats_table_file;
 164         struct dentry *rs_sta_dbgfs_rate_scale_data_file;
 165         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
 166         u32 dbg_fixed_rate;
 167 #endif
 168         struct iwl_priv *drv;
 169
 170         /* used to be in sta_info */
 171         int last_txrate_idx;
 172         /* last tx rate_n_flags */
 173         u32 last_rate_n_flags;
 174         /* packets destined for this STA are aggregated */
 175         u8 is_agg;
 176 };
 177
 178 static void rs_rate_scale_perform(struct iwl_priv *priv,
 179                                    struct sk_buff *skb,
 180                                    struct ieee80211_sta *sta,
 181                                    struct iwl_lq_sta *lq_sta);
 182 static void rs_fill_link_cmd(struct iwl_priv *priv,
 183                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
 184
 185
 186 #ifdef CONFIG_MAC80211_DEBUGFS
 187 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 188                              u32 *rate_n_flags, int index);
 189 #else
 190 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 191                              u32 *rate_n_flags, int index)
 192 {}
 193 #endif
 194
 195 /**
 196  * The following tables contain the expected throughput metrics for all rates
 197  *
 198  *      1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
 199  *
 200  * where invalid entries are zeros.
 201  *
 202  * CCK rates are only valid in legacy table and will only be used in G
 203  * (2.4 GHz) band.
 204  */
 205
 206 static s32 expected_tpt_legacy[IWL_RATE_COUNT] = {
 207         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 0
 208 };
 209
 210 static s32 expected_tpt_siso20MHz[4][IWL_RATE_COUNT] = {
 211         {0, 0, 0, 0, 42, 0,  76, 102, 124, 158, 183, 193, 202}, /* Norm */
 212         {0, 0, 0, 0, 46, 0,  82, 110, 132, 167, 192, 202, 210}, /* SGI */
 213         {0, 0, 0, 0, 48, 0,  93, 135, 176, 251, 319, 351, 381}, /* AGG */
 214         {0, 0, 0, 0, 53, 0, 102, 149, 193, 275, 348, 381, 413}, /* AGG+SGI */
 215 };
 216
 217 static s32 expected_tpt_siso40MHz[4][IWL_RATE_COUNT] = {
 218         {0, 0, 0, 0,  77, 0, 127, 160, 184, 220, 242, 250, 257}, /* Norm */
 219         {0, 0, 0, 0,  83, 0, 135, 169, 193, 229, 250, 257, 264}, /* SGI */
 220         {0, 0, 0, 0,  96, 0, 182, 259, 328, 451, 553, 598, 640}, /* AGG */
 221         {0, 0, 0, 0, 106, 0, 199, 282, 357, 487, 593, 640, 683}, /* AGG+SGI */
 222 };
 223
 224 static s32 expected_tpt_mimo2_20MHz[4][IWL_RATE_COUNT] = {
 225         {0, 0, 0, 0,  74, 0, 123, 155, 179, 213, 235, 243, 250}, /* Norm */
 226         {0, 0, 0, 0,  81, 0, 131, 164, 187, 221, 242, 250, 256}, /* SGI */
 227         {0, 0, 0, 0,  92, 0, 175, 250, 317, 436, 534, 578, 619}, /* AGG */
 228         {0, 0, 0, 0, 102, 0, 192, 273, 344, 470, 573, 619, 660}, /* AGG+SGI*/
 229 };
 230
 231 static s32 expected_tpt_mimo2_40MHz[4][IWL_RATE_COUNT] = {
 232         {0, 0, 0, 0, 123, 0, 182, 214, 235, 264, 279, 285, 289}, /* Norm */
 233         {0, 0, 0, 0, 131, 0, 191, 222, 242, 270, 284, 289, 293}, /* SGI */
 234         {0, 0, 0, 0, 180, 0, 327, 446, 545, 708, 828, 878, 922}, /* AGG */
 235         {0, 0, 0, 0, 197, 0, 355, 481, 584, 752, 872, 922, 966}, /* AGG+SGI */
 236 };
 237
 238 static s32 expected_tpt_mimo3_20MHz[4][IWL_RATE_COUNT] = {
 239         {0, 0, 0, 0,  99, 0, 153, 186, 208, 239, 256, 263, 268}, /* Norm */
 240         {0, 0, 0, 0, 106, 0, 162, 194, 215, 246, 262, 268, 273}, /* SGI */
 241         {0, 0, 0, 0, 134, 0, 249, 346, 431, 574, 685, 732, 775}, /* AGG */
 242         {0, 0, 0, 0, 148, 0, 272, 376, 465, 614, 727, 775, 818}, /* AGG+SGI */
 243 };
 244
 245 static s32 expected_tpt_mimo3_40MHz[4][IWL_RATE_COUNT] = {
 246         {0, 0, 0, 0, 152, 0, 211, 239, 255, 279,  290,  294,  297}, /* Norm */
 247         {0, 0, 0, 0, 160, 0, 219, 245, 261, 284,  294,  297,  300}, /* SGI */
 248         {0, 0, 0, 0, 254, 0, 443, 584, 695, 868,  984, 1030, 1070}, /* AGG */
 249         {0, 0, 0, 0, 277, 0, 478, 624, 737, 911, 1026, 1070, 1109}, /* AGG+SGI */
 250 };
 251
 252 /* mbps, mcs */
 253 const static struct iwl_rate_mcs_info iwl_rate_mcs[IWL_RATE_COUNT] = {
 254         {  "1", "BPSK DSSS"},
 255         {  "2", "QPSK DSSS"},
 256         {"5.5", "BPSK CCK"},
 257         { "11", "QPSK CCK"},
 258         {  "6", "BPSK 1/2"},
 259         {  "9", "BPSK 1/2"},
 260         { "12", "QPSK 1/2"},
 261         { "18", "QPSK 3/4"},
 262         { "24", "16QAM 1/2"},
 263         { "36", "16QAM 3/4"},
 264         { "48", "64QAM 2/3"},
 265         { "54", "64QAM 3/4"},
 266         { "60", "64QAM 5/6"},
 267 };
 268
 269 #define MCS_INDEX_PER_STREAM    (8)
 270
 271 static inline u8 rs_extract_rate(u32 rate_n_flags)
 272 {
 273         return (u8)(rate_n_flags & 0xFF);
 274 }
 275
 276 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
 277 {
 278         window->data = 0;
 279         window->success_counter = 0;
 280         window->success_ratio = IWL_INVALID_VALUE;
 281         window->counter = 0;
 282         window->average_tpt = IWL_INVALID_VALUE;
 283         window->stamp = 0;
 284 }
 285
 286 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
 287 {
 288         return (ant_type & valid_antenna) == ant_type;
 289 }
 290
 291 /*
 292  *      removes the old data from the statistics. All data that is older than
 293  *      TID_MAX_TIME_DIFF, will be deleted.
 294  */
 295 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
 296 {
 297         /* The oldest age we want to keep */
 298         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
 299
 300         while (tl->queue_count &&
 301                (tl->time_stamp < oldest_time)) {
 302                 tl->total -= tl->packet_count[tl->head];
 303                 tl->packet_count[tl->head] = 0;
 304                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
 305                 tl->queue_count--;
 306                 tl->head++;
 307                 if (tl->head >= TID_QUEUE_MAX_SIZE)
 308                         tl->head = 0;
 309         }
 310 }
 311
 312 /*
 313  *      increment traffic load value for tid and also remove
 314  *      any old values if passed the certain time period
 315  */
 316 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
 317                            struct ieee80211_hdr *hdr)
 318 {
 319         u32 curr_time = jiffies_to_msecs(jiffies);
 320         u32 time_diff;
 321         s32 index;
 322         struct iwl_traffic_load *tl = NULL;
 323         u8 tid;
 324
 325         if (ieee80211_is_data_qos(hdr->frame_control)) {
 326                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 327                 tid = qc[0] & 0xf;
 328         } else
 329                 return MAX_TID_COUNT;
 330
 331         if (unlikely(tid >= TID_MAX_LOAD_COUNT))
 332                 return MAX_TID_COUNT;
 333
 334         tl = &lq_data->load[tid];
 335
 336         curr_time -= curr_time % TID_ROUND_VALUE;
 337
 338         /* Happens only for the first packet. Initialize the data */
 339         if (!(tl->queue_count)) {
 340                 tl->total = 1;
 341                 tl->time_stamp = curr_time;
 342                 tl->queue_count = 1;
 343                 tl->head = 0;
 344                 tl->packet_count[0] = 1;
 345                 return MAX_TID_COUNT;
 346         }
 347
 348         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 349         index = time_diff / TID_QUEUE_CELL_SPACING;
 350
 351         /* The history is too long: remove data that is older than */
 352         /* TID_MAX_TIME_DIFF */
 353         if (index >= TID_QUEUE_MAX_SIZE)
 354                 rs_tl_rm_old_stats(tl, curr_time);
 355
 356         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
 357         tl->packet_count[index] = tl->packet_count[index] + 1;
 358         tl->total = tl->total + 1;
 359
 360         if ((index + 1) > tl->queue_count)
 361                 tl->queue_count = index + 1;
 362
 363         return tid;
 364 }
 365
 366 /*
 367         get the traffic load value for tid
 368 */
 369 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
 370 {
 371         u32 curr_time = jiffies_to_msecs(jiffies);
 372         u32 time_diff;
 373         s32 index;
 374         struct iwl_traffic_load *tl = NULL;
 375
 376         if (tid >= TID_MAX_LOAD_COUNT)
 377                 return 0;
 378
 379         tl = &(lq_data->load[tid]);
 380
 381         curr_time -= curr_time % TID_ROUND_VALUE;
 382
 383         if (!(tl->queue_count))
 384                 return 0;
 385
 386         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 387         index = time_diff / TID_QUEUE_CELL_SPACING;
 388
 389         /* The history is too long: remove data that is older than */
 390         /* TID_MAX_TIME_DIFF */
 391         if (index >= TID_QUEUE_MAX_SIZE)
 392                 rs_tl_rm_old_stats(tl, curr_time);
 393
 394         return tl->total;
 395 }
 396
 397 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
 398                                       struct iwl_lq_sta *lq_data, u8 tid,
 399                                       struct ieee80211_sta *sta)
 400 {
 401         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
 402                 IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n",
 403                                 sta->addr, tid);
 404                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
 405         }
 406 }
 407
 408 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
 409                               struct iwl_lq_sta *lq_data,
 410                               struct ieee80211_sta *sta)
 411 {
 412         if ((tid < TID_MAX_LOAD_COUNT))
 413                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 414         else if (tid == IWL_AGG_ALL_TID)
 415                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
 416                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 417         if (priv->cfg->use_rts_for_ht) {
 418                 /*
 419                  * switch to RTS/CTS if it is the prefer protection method
 420                  * for HT traffic
 421                  */
 422                 IWL_DEBUG_HT(priv, "use RTS/CTS protection for HT\n");
 423                 priv->staging_rxon.flags &= ~RXON_FLG_SELF_CTS_EN;
 424                 iwlcore_commit_rxon(priv);
 425         }
 426 }
 427
 428 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
 429 {
 430         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
 431                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
 432                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
 433 }
 434
 435 /**
 436  * rs_collect_tx_data - Update the success/failure sliding window
 437  *
 438  * We keep a sliding window of the last 62 packets transmitted
 439  * at this rate.  window->data contains the bitmask of successful
 440  * packets.
 441  */
 442 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
 443                               int scale_index, s32 tpt, int attempts,
 444                               int successes)
 445 {
 446         struct iwl_rate_scale_data *window = NULL;
 447         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 448         s32 fail_count;
 449
 450         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 451                 return -EINVAL;
 452
 453         /* Select window for current tx bit rate */
 454         window = &(windows[scale_index]);
 455
 456         /*
 457          * Keep track of only the latest 62 tx frame attempts in this rate's
 458          * history window; anything older isn't really relevant any more.
 459          * If we have filled up the sliding window, drop the oldest attempt;
 460          * if the oldest attempt (highest bit in bitmap) shows "success",
 461          * subtract "1" from the success counter (this is the main reason
 462          * we keep these bitmaps!).
 463          */
 464         while (attempts > 0) {
 465                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 466
 467                         /* remove earliest */
 468                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 469
 470                         if (window->data & mask) {
 471                                 window->data &= ~mask;
 472                                 window->success_counter--;
 473                         }
 474                 }
 475
 476                 /* Increment frames-attempted counter */
 477                 window->counter++;
 478
 479                 /* Shift bitmap by one frame to throw away oldest history */
 480                 window->data <<= 1;
 481
 482                 /* Mark the most recent #successes attempts as successful */
 483                 if (successes > 0) {
 484                         window->success_counter++;
 485                         window->data |= 0x1;
 486                         successes--;
 487                 }
 488
 489                 attempts--;
 490         }
 491
 492         /* Calculate current success ratio, avoid divide-by-0! */
 493         if (window->counter > 0)
 494                 window->success_ratio = 128 * (100 * window->success_counter)
 495                                         / window->counter;
 496         else
 497                 window->success_ratio = IWL_INVALID_VALUE;
 498
 499         fail_count = window->counter - window->success_counter;
 500
 501         /* Calculate average throughput, if we have enough history. */
 502         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 503             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 504                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 505         else
 506                 window->average_tpt = IWL_INVALID_VALUE;
 507
 508         /* Tag this window as having been updated */
 509         window->stamp = jiffies;
 510
 511         return 0;
 512 }
 513
 514 /*
 515  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 516  */
 517 /* FIXME:RS:remove this function and put the flags statically in the table */
 518 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 519                                  struct iwl_scale_tbl_info *tbl,
 520                                  int index, u8 use_green)
 521 {
 522         u32 rate_n_flags = 0;
 523
 524         if (is_legacy(tbl->lq_type)) {
 525                 rate_n_flags = iwl_rates[index].plcp;
 526                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 527                         rate_n_flags |= RATE_MCS_CCK_MSK;
 528
 529         } else if (is_Ht(tbl->lq_type)) {
 530                 if (index > IWL_LAST_OFDM_RATE) {
 531                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 532                         index = IWL_LAST_OFDM_RATE;
 533                 }
 534                 rate_n_flags = RATE_MCS_HT_MSK;
 535
 536                 if (is_siso(tbl->lq_type))
 537                         rate_n_flags |= iwl_rates[index].plcp_siso;
 538                 else if (is_mimo2(tbl->lq_type))
 539                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 540                 else
 541                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 542         } else {
 543                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 544         }
 545
 546         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 547                                                      RATE_MCS_ANT_ABC_MSK);
 548
 549         if (is_Ht(tbl->lq_type)) {
 550                 if (tbl->is_ht40) {
 551                         if (tbl->is_dup)
 552                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 553                         else
 554                                 rate_n_flags |= RATE_MCS_HT40_MSK;
 555                 }
 556                 if (tbl->is_SGI)
 557                         rate_n_flags |= RATE_MCS_SGI_MSK;
 558
 559                 if (use_green) {
 560                         rate_n_flags |= RATE_MCS_GF_MSK;
 561                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 562                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 563                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 564                         }
 565                 }
 566         }
 567         return rate_n_flags;
 568 }
 569
 570 /*
 571  * Interpret uCode API's rate_n_flags format,
 572  * fill "search" or "active" tx mode table.
 573  */
 574 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 575                                     enum ieee80211_band band,
 576                                     struct iwl_scale_tbl_info *tbl,
 577                                     int *rate_idx)
 578 {
 579         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 580         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 581         u8 mcs;
 582
 583         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 584
 585         if (*rate_idx  == IWL_RATE_INVALID) {
 586                 *rate_idx = -1;
 587                 return -EINVAL;
 588         }
 589         tbl->is_SGI = 0;        /* default legacy setup */
 590         tbl->is_ht40 = 0;
 591         tbl->is_dup = 0;
 592         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 593         tbl->lq_type = LQ_NONE;
 594         tbl->max_search = IWL_MAX_SEARCH;
 595
 596         /* legacy rate format */
 597         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 598                 if (num_of_ant == 1) {
 599                         if (band == IEEE80211_BAND_5GHZ)
 600                                 tbl->lq_type = LQ_A;
 601                         else
 602                                 tbl->lq_type = LQ_G;
 603                 }
 604         /* HT rate format */
 605         } else {
 606                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 607                         tbl->is_SGI = 1;
 608
 609                 if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
 610                     (rate_n_flags & RATE_MCS_DUP_MSK))
 611                         tbl->is_ht40 = 1;
 612
 613                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 614                         tbl->is_dup = 1;
 615
 616                 mcs = rs_extract_rate(rate_n_flags);
 617
 618                 /* SISO */
 619                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 620                         if (num_of_ant == 1)
 621                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 622                 /* MIMO2 */
 623                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 624                         if (num_of_ant == 2)
 625                                 tbl->lq_type = LQ_MIMO2;
 626                 /* MIMO3 */
 627                 } else {
 628                         if (num_of_ant == 3) {
 629                                 tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
 630                                 tbl->lq_type = LQ_MIMO3;
 631                         }
 632                 }
 633         }
 634         return 0;
 635 }
 636
 637 /* switch to another antenna/antennas and return 1 */
 638 /* if no other valid antenna found, return 0 */
 639 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 640                              struct iwl_scale_tbl_info *tbl)
 641 {
 642         u8 new_ant_type;
 643
 644         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 645                 return 0;
 646
 647         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 648                 return 0;
 649
 650         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 651
 652         while ((new_ant_type != tbl->ant_type) &&
 653                !rs_is_valid_ant(valid_ant, new_ant_type))
 654                 new_ant_type = ant_toggle_lookup[new_ant_type];
 655
 656         if (new_ant_type == tbl->ant_type)
 657                 return 0;
 658
 659         tbl->ant_type = new_ant_type;
 660         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 661         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 662         return 1;
 663 }
 664
 665 /**
 666  * Green-field mode is valid if the station supports it and
 667  * there are no non-GF stations present in the BSS.
 668  */
 669 static inline u8 rs_use_green(struct ieee80211_sta *sta,
 670                               struct iwl_ht_config *ht_conf)
 671 {
 672         return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
 673                 !(ht_conf->non_GF_STA_present);
 674 }
 675
 676 /**
 677  * rs_get_supported_rates - get the available rates
 678  *
 679  * if management frame or broadcast frame only return
 680  * basic available rates.
 681  *
 682  */
 683 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 684                                   struct ieee80211_hdr *hdr,
 685                                   enum iwl_table_type rate_type)
 686 {
 687         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 688             lq_sta->active_rate_basic)
 689                 return lq_sta->active_rate_basic;
 690
 691         if (is_legacy(rate_type)) {
 692                 return lq_sta->active_legacy_rate;
 693         } else {
 694                 if (is_siso(rate_type))
 695                         return lq_sta->active_siso_rate;
 696                 else if (is_mimo2(rate_type))
 697                         return lq_sta->active_mimo2_rate;
 698                 else
 699                         return lq_sta->active_mimo3_rate;
 700         }
 701 }
 702
 703 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 704                                 int rate_type)
 705 {
 706         u8 high = IWL_RATE_INVALID;
 707         u8 low = IWL_RATE_INVALID;
 708
 709         /* 802.11A or ht walks to the next literal adjacent rate in
 710          * the rate table */
 711         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 712                 int i;
 713                 u32 mask;
 714
 715                 /* Find the previous rate that is in the rate mask */
 716                 i = index - 1;
 717                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 718                         if (rate_mask & mask) {
 719                                 low = i;
 720                                 break;
 721                         }
 722                 }
 723
 724                 /* Find the next rate that is in the rate mask */
 725                 i = index + 1;
 726                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 727                         if (rate_mask & mask) {
 728                                 high = i;
 729                                 break;
 730                         }
 731                 }
 732
 733                 return (high << 8) | low;
 734         }
 735
 736         low = index;
 737         while (low != IWL_RATE_INVALID) {
 738                 low = iwl_rates[low].prev_rs;
 739                 if (low == IWL_RATE_INVALID)
 740                         break;
 741                 if (rate_mask & (1 << low))
 742                         break;
 743                 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
 744         }
 745
 746         high = index;
 747         while (high != IWL_RATE_INVALID) {
 748                 high = iwl_rates[high].next_rs;
 749                 if (high == IWL_RATE_INVALID)
 750                         break;
 751                 if (rate_mask & (1 << high))
 752                         break;
 753                 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
 754         }
 755
 756         return (high << 8) | low;
 757 }
 758
 759 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 760                              struct iwl_scale_tbl_info *tbl,
 761                              u8 scale_index, u8 ht_possible)
 762 {
 763         s32 low;
 764         u16 rate_mask;
 765         u16 high_low;
 766         u8 switch_to_legacy = 0;
 767         u8 is_green = lq_sta->is_green;
 768         struct iwl_priv *priv = lq_sta->drv;
 769
 770         /* check if we need to switch from HT to legacy rates.
 771          * assumption is that mandatory rates (1Mbps or 6Mbps)
 772          * are always supported (spec demand) */
 773         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 774                 switch_to_legacy = 1;
 775                 scale_index = rs_ht_to_legacy[scale_index];
 776                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 777                         tbl->lq_type = LQ_A;
 778                 else
 779                         tbl->lq_type = LQ_G;
 780
 781                 if (num_of_ant(tbl->ant_type) > 1)
 782                         tbl->ant_type =
 783                                 first_antenna(priv->hw_params.valid_tx_ant);
 784
 785                 tbl->is_ht40 = 0;
 786                 tbl->is_SGI = 0;
 787                 tbl->max_search = IWL_MAX_SEARCH;
 788         }
 789
 790         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 791
 792         /* Mask with station rate restriction */
 793         if (is_legacy(tbl->lq_type)) {
 794                 /* supp_rates has no CCK bits in A mode */
 795                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 796                         rate_mask  = (u16)(rate_mask &
 797                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 798                 else
 799                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 800         }
 801
 802         /* If we switched from HT to legacy, check current rate */
 803         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 804                 low = scale_index;
 805                 goto out;
 806         }
 807
 808         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 809                                         tbl->lq_type);
 810         low = high_low & 0xff;
 811
 812         if (low == IWL_RATE_INVALID)
 813                 low = scale_index;
 814
 815 out:
 816         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 817 }
 818
 819 /*
 820  * Simple function to compare two rate scale table types
 821  */
 822 static bool table_type_matches(struct iwl_scale_tbl_info *a,
 823                                struct iwl_scale_tbl_info *b)
 824 {
 825         return (a->lq_type == b->lq_type) && (a->ant_type == b->ant_type) &&
 826                 (a->is_SGI == b->is_SGI);
 827 }
 828 /*
 829  * Static function to get the expected throughput from an iwl_scale_tbl_info
 830  * that wraps a NULL pointer check
 831  */
 832 static s32 get_expected_tpt(struct iwl_scale_tbl_info *tbl, int rs_index)
 833 {
 834         if (tbl->expected_tpt)
 835                 return tbl->expected_tpt[rs_index];
 836         return 0;
 837 }
 838
 839 /*
 840  * mac80211 sends us Tx status
 841  */
 842 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 843                          struct ieee80211_sta *sta, void *priv_sta,
 844                          struct sk_buff *skb)
 845 {
 846         int legacy_success;
 847         int retries;
 848         int rs_index, mac_index, i;
 849         struct iwl_lq_sta *lq_sta = priv_sta;
 850         struct iwl_link_quality_cmd *table;
 851         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 852         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 853         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 854         struct iwl_rate_scale_data *window = NULL;
 855         enum mac80211_rate_control_flags mac_flags;
 856         u32 tx_rate;
 857         struct iwl_scale_tbl_info tbl_type;
 858         struct iwl_scale_tbl_info *curr_tbl, *other_tbl;
 859         s32 tpt = 0;
 860
 861         IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 862
 863         if (!ieee80211_is_data(hdr->frame_control) ||
 864             info->flags & IEEE80211_TX_CTL_NO_ACK)
 865                 return;
 866
 867         /* This packet was aggregated but doesn't carry status info */
 868         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 869             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 870                 return;
 871
 872         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 873             !lq_sta->ibss_sta_added)
 874                 return;
 875
 876         /*
 877          * Ignore this Tx frame response if its initial rate doesn't match
 878          * that of latest Link Quality command.  There may be stragglers
 879          * from a previous Link Quality command, but we're no longer interested
 880          * in those; they're either from the "active" mode while we're trying
 881          * to check "search" mode, or a prior "search" mode after we've moved
 882          * to a new "search" mode (which might become the new "active" mode).
 883          */
 884         table = &lq_sta->lq;
 885         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 886         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 887         if (priv->band == IEEE80211_BAND_5GHZ)
 888                 rs_index -= IWL_FIRST_OFDM_RATE;
 889         mac_flags = info->status.rates[0].flags;
 890         mac_index = info->status.rates[0].idx;
 891         /* For HT packets, map MCS to PLCP */
 892         if (mac_flags & IEEE80211_TX_RC_MCS) {
 893                 mac_index &= RATE_MCS_CODE_MSK; /* Remove # of streams */
 894                 if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE))
 895                         mac_index++;
 896                 /*
 897                  * mac80211 HT index is always zero-indexed; we need to move
 898                  * HT OFDM rates after CCK rates in 2.4 GHz band
 899                  */
 900                 if (priv->band == IEEE80211_BAND_2GHZ)
 901                         mac_index += IWL_FIRST_OFDM_RATE;
 902         }
 903         /* Here we actually compare this rate to the latest LQ command */
 904         if ((mac_index < 0) ||
 905             (tbl_type.is_SGI != !!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) ||
 906             (tbl_type.is_ht40 != !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 907             (tbl_type.is_dup != !!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) ||
 908             (tbl_type.ant_type != info->antenna_sel_tx) ||
 909             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(mac_flags & IEEE80211_TX_RC_MCS)) ||
 910             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 911             (rs_index != mac_index)) {
 912                 IWL_DEBUG_RATE(priv, "initial rate %d does not match %d (0x%x)\n", mac_index, rs_index, tx_rate);
 913                 /*
 914                  * Since rates mis-match, the last LQ command may have failed.
 915                  * After IWL_MISSED_RATE_MAX mis-matches, resync the uCode with
 916                  * ... driver.
 917                  */
 918                 lq_sta->missed_rate_counter++;
 919                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 920                         lq_sta->missed_rate_counter = 0;
 921                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 922                 }
 923                 /* Regardless, ignore this status info for outdated rate */
 924                 return;
 925         } else
 926                 /* Rate did match, so reset the missed_rate_counter */
 927                 lq_sta->missed_rate_counter = 0;
 928
 929         /* Figure out if rate scale algorithm is in active or search table */
 930         if (table_type_matches(&tbl_type,
 931                                 &(lq_sta->lq_info[lq_sta->active_tbl]))) {
 932                 curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 933                 other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 934         } else if (table_type_matches(&tbl_type,
 935                                 &lq_sta->lq_info[1 - lq_sta->active_tbl])) {
 936                 curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
 937                 other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
 938         } else {
 939                 IWL_DEBUG_RATE(priv, "Neither active nor search matches tx rate\n");
 940                 return;
 941         }
 942         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 943
 944         /*
 945          * Updating the frame history depends on whether packets were
 946          * aggregated.
 947          *
 948          * For aggregation, all packets were transmitted at the same rate, the
 949          * first index into rate scale table.
 950          */
 951         if (info->flags & IEEE80211_TX_STAT_AMPDU) {
 952                 tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 953                 rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type,
 954                                 &rs_index);
 955                 tpt = get_expected_tpt(curr_tbl, rs_index);
 956                 rs_collect_tx_data(window, rs_index, tpt,
 957                                    info->status.ampdu_ack_len,
 958                                    info->status.ampdu_ack_map);
 959
 960                 /* Update success/fail counts if not searching for new mode */
 961                 if (lq_sta->stay_in_tbl) {
 962                         lq_sta->total_success += info->status.ampdu_ack_map;
 963                         lq_sta->total_failed += (info->status.ampdu_ack_len -
 964                                         info->status.ampdu_ack_map);
 965                 }
 966         } else {
 967         /*
 968          * For legacy, update frame history with for each Tx retry.
 969          */
 970                 retries = info->status.rates[0].count - 1;
 971                 /* HW doesn't send more than 15 retries */
 972                 retries = min(retries, 15);
 973
 974                 /* The last transmission may have been successful */
 975                 legacy_success = !!(info->flags & IEEE80211_TX_STAT_ACK);
 976                 /* Collect data for each rate used during failed TX attempts */
 977                 for (i = 0; i <= retries; ++i) {
 978                         tx_rate = le32_to_cpu(table->rs_table[i].rate_n_flags);
 979                         rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 980                                         &tbl_type, &rs_index);
 981                         /*
 982                          * Only collect stats if retried rate is in the same RS
 983                          * table as active/search.
 984                          */
 985                         if (table_type_matches(&tbl_type, curr_tbl))
 986                                 tpt = get_expected_tpt(curr_tbl, rs_index);
 987                         else if (table_type_matches(&tbl_type, other_tbl))
 988                                 tpt = get_expected_tpt(other_tbl, rs_index);
 989                         else
 990                                 continue;
 991
 992                         /* Constants mean 1 transmission, 0 successes */
 993                         if (i < retries)
 994                                 rs_collect_tx_data(window, rs_index, tpt, 1,
 995                                                 0);
 996                         else
 997                                 rs_collect_tx_data(window, rs_index, tpt, 1,
 998                                                 legacy_success);
 999                 }
1000
1001                 /* Update success/fail counts if not searching for new mode */
1002                 if (lq_sta->stay_in_tbl) {
1003                         lq_sta->total_success += legacy_success;
1004                         lq_sta->total_failed += retries + (1 - legacy_success);
1005                 }
1006         }
1007         /* The last TX rate is cached in lq_sta; it's set in if/else above */
1008         lq_sta->last_rate_n_flags = tx_rate;
1009
1010         /* See if there's a better rate or modulation mode to try. */
1011         if (sta && sta->supp_rates[sband->band])
1012                 rs_rate_scale_perform(priv, skb, sta, lq_sta);
1013 }
1014
1015 /*
1016  * Begin a period of staying with a selected modulation mode.
1017  * Set "stay_in_tbl" flag to prevent any mode switches.
1018  * Set frame tx success limits according to legacy vs. high-throughput,
1019  * and reset overall (spanning all rates) tx success history statistics.
1020  * These control how long we stay using same modulation mode before
1021  * searching for a new mode.
1022  */
1023 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
1024                                  struct iwl_lq_sta *lq_sta)
1025 {
1026         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
1027         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
1028         if (is_legacy) {
1029                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
1030                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
1031                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
1032         } else {
1033                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
1034                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
1035                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
1036         }
1037         lq_sta->table_count = 0;
1038         lq_sta->total_failed = 0;
1039         lq_sta->total_success = 0;
1040         lq_sta->flush_timer = jiffies;
1041         lq_sta->action_counter = 0;
1042 }
1043
1044 /*
1045  * Find correct throughput table for given mode of modulation
1046  */
1047 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
1048                                       struct iwl_scale_tbl_info *tbl)
1049 {
1050         /* Used to choose among HT tables */
1051         s32 (*ht_tbl_pointer)[IWL_RATE_COUNT];
1052
1053         /* Check for invalid LQ type */
1054         if (WARN_ON_ONCE(!is_legacy(tbl->lq_type) && !is_Ht(tbl->lq_type))) {
1055                 tbl->expected_tpt = expected_tpt_legacy;
1056                 return;
1057         }
1058
1059         /* Legacy rates have only one table */
1060         if (is_legacy(tbl->lq_type)) {
1061                 tbl->expected_tpt = expected_tpt_legacy;
1062                 return;
1063         }
1064
1065         /* Choose among many HT tables depending on number of streams
1066          * (SISO/MIMO2/MIMO3), channel width (20/40), SGI, and aggregation
1067          * status */
1068         if (is_siso(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
1069                 ht_tbl_pointer = expected_tpt_siso20MHz;
1070         else if (is_siso(tbl->lq_type))
1071                 ht_tbl_pointer = expected_tpt_siso40MHz;
1072         else if (is_mimo2(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
1073                 ht_tbl_pointer = expected_tpt_mimo2_20MHz;
1074         else if (is_mimo2(tbl->lq_type))
1075                 ht_tbl_pointer = expected_tpt_mimo2_40MHz;
1076         else if (is_mimo3(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
1077                 ht_tbl_pointer = expected_tpt_mimo3_20MHz;
1078         else /* if (is_mimo3(tbl->lq_type)) <-- must be true */
1079                 ht_tbl_pointer = expected_tpt_mimo3_40MHz;
1080
1081         if (!tbl->is_SGI && !lq_sta->is_agg)            /* Normal */
1082                 tbl->expected_tpt = ht_tbl_pointer[0];
1083         else if (tbl->is_SGI && !lq_sta->is_agg)        /* SGI */
1084                 tbl->expected_tpt = ht_tbl_pointer[1];
1085         else if (!tbl->is_SGI && lq_sta->is_agg)        /* AGG */
1086                 tbl->expected_tpt = ht_tbl_pointer[2];
1087         else                                            /* AGG+SGI */
1088                 tbl->expected_tpt = ht_tbl_pointer[3];
1089 }
1090
1091 /*
1092  * Find starting rate for new "search" high-throughput mode of modulation.
1093  * Goal is to find lowest expected rate (under perfect conditions) that is
1094  * above the current measured throughput of "active" mode, to give new mode
1095  * a fair chance to prove itself without too many challenges.
1096  *
1097  * This gets called when transitioning to more aggressive modulation
1098  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1099  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1100  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1101  * bit rate will typically need to increase, but not if performance was bad.
1102  */
1103 static s32 rs_get_best_rate(struct iwl_priv *priv,
1104                             struct iwl_lq_sta *lq_sta,
1105                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1106                             u16 rate_mask, s8 index)
1107 {
1108         /* "active" values */
1109         struct iwl_scale_tbl_info *active_tbl =
1110             &(lq_sta->lq_info[lq_sta->active_tbl]);
1111         s32 active_sr = active_tbl->win[index].success_ratio;
1112         s32 active_tpt = active_tbl->expected_tpt[index];
1113
1114         /* expected "search" throughput */
1115         s32 *tpt_tbl = tbl->expected_tpt;
1116
1117         s32 new_rate, high, low, start_hi;
1118         u16 high_low;
1119         s8 rate = index;
1120
1121         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1122
1123         for (; ;) {
1124                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1125                                                 tbl->lq_type);
1126
1127                 low = high_low & 0xff;
1128                 high = (high_low >> 8) & 0xff;
1129
1130                 /*
1131                  * Lower the "search" bit rate, to give new "search" mode
1132                  * approximately the same throughput as "active" if:
1133                  *
1134                  * 1) "Active" mode has been working modestly well (but not
1135                  *    great), and expected "search" throughput (under perfect
1136                  *    conditions) at candidate rate is above the actual
1137                  *    measured "active" throughput (but less than expected
1138                  *    "active" throughput under perfect conditions).
1139                  * OR
1140                  * 2) "Active" mode has been working perfectly or very well
1141                  *    and expected "search" throughput (under perfect
1142                  *    conditions) at candidate rate is above expected
1143                  *    "active" throughput (under perfect conditions).
1144                  */
1145                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1146                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1147                       (active_sr <= IWL_RATE_HIGH_TH) &&
1148                       (tpt_tbl[rate] <= active_tpt))) ||
1149                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1150                      (tpt_tbl[rate] > active_tpt))) {
1151
1152                         /* (2nd or later pass)
1153                          * If we've already tried to raise the rate, and are
1154                          * now trying to lower it, use the higher rate. */
1155                         if (start_hi != IWL_RATE_INVALID) {
1156                                 new_rate = start_hi;
1157                                 break;
1158                         }
1159
1160                         new_rate = rate;
1161
1162                         /* Loop again with lower rate */
1163                         if (low != IWL_RATE_INVALID)
1164                                 rate = low;
1165
1166                         /* Lower rate not available, use the original */
1167                         else
1168                                 break;
1169
1170                 /* Else try to raise the "search" rate to match "active" */
1171                 } else {
1172                         /* (2nd or later pass)
1173                          * If we've already tried to lower the rate, and are
1174                          * now trying to raise it, use the lower rate. */
1175                         if (new_rate != IWL_RATE_INVALID)
1176                                 break;
1177
1178                         /* Loop again with higher rate */
1179                         else if (high != IWL_RATE_INVALID) {
1180                                 start_hi = high;
1181                                 rate = high;
1182
1183                         /* Higher rate not available, use the original */
1184                         } else {
1185                                 new_rate = rate;
1186                                 break;
1187                         }
1188                 }
1189         }
1190
1191         return new_rate;
1192 }
1193
1194 /*
1195  * Set up search table for MIMO2
1196  */
1197 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1198                              struct iwl_lq_sta *lq_sta,
1199                              struct ieee80211_conf *conf,
1200                              struct ieee80211_sta *sta,
1201                              struct iwl_scale_tbl_info *tbl, int index)
1202 {
1203         u16 rate_mask;
1204         s32 rate;
1205         s8 is_green = lq_sta->is_green;
1206
1207         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1208                 return -1;
1209
1210         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1211                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1212                 return -1;
1213
1214         /* Need both Tx chains/antennas to support MIMO */
1215         if (priv->hw_params.tx_chains_num < 2)
1216                 return -1;
1217
1218         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1219
1220         tbl->lq_type = LQ_MIMO2;
1221         tbl->is_dup = lq_sta->is_dup;
1222         tbl->action = 0;
1223         tbl->max_search = IWL_MAX_SEARCH;
1224         rate_mask = lq_sta->active_mimo2_rate;
1225
1226         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1227                 tbl->is_ht40 = 1;
1228         else
1229                 tbl->is_ht40 = 0;
1230
1231         rs_set_expected_tpt_table(lq_sta, tbl);
1232
1233         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1234
1235         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1236         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1237                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1238                                                 rate, rate_mask);
1239                 return -1;
1240         }
1241         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1242
1243         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1244                      tbl->current_rate, is_green);
1245         return 0;
1246 }
1247
1248 /*
1249  * Set up search table for MIMO3
1250  */
1251 static int rs_switch_to_mimo3(struct iwl_priv *priv,
1252                              struct iwl_lq_sta *lq_sta,
1253                              struct ieee80211_conf *conf,
1254                              struct ieee80211_sta *sta,
1255                              struct iwl_scale_tbl_info *tbl, int index)
1256 {
1257         u16 rate_mask;
1258         s32 rate;
1259         s8 is_green = lq_sta->is_green;
1260
1261         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1262                 return -1;
1263
1264         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1265                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1266                 return -1;
1267
1268         /* Need both Tx chains/antennas to support MIMO */
1269         if (priv->hw_params.tx_chains_num < 3)
1270                 return -1;
1271
1272         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO3\n");
1273
1274         tbl->lq_type = LQ_MIMO3;
1275         tbl->is_dup = lq_sta->is_dup;
1276         tbl->action = 0;
1277         tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
1278         rate_mask = lq_sta->active_mimo3_rate;
1279
1280         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1281                 tbl->is_ht40 = 1;
1282         else
1283                 tbl->is_ht40 = 0;
1284
1285         rs_set_expected_tpt_table(lq_sta, tbl);
1286
1287         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1288
1289         IWL_DEBUG_RATE(priv, "LQ: MIMO3 best rate %d mask %X\n",
1290                 rate, rate_mask);
1291         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1292                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1293                                                 rate, rate_mask);
1294                 return -1;
1295         }
1296         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1297
1298         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1299                      tbl->current_rate, is_green);
1300         return 0;
1301 }
1302
1303 /*
1304  * Set up search table for SISO
1305  */
1306 static int rs_switch_to_siso(struct iwl_priv *priv,
1307                              struct iwl_lq_sta *lq_sta,
1308                              struct ieee80211_conf *conf,
1309                              struct ieee80211_sta *sta,
1310                              struct iwl_scale_tbl_info *tbl, int index)
1311 {
1312         u16 rate_mask;
1313         u8 is_green = lq_sta->is_green;
1314         s32 rate;
1315
1316         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1317                 return -1;
1318
1319         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1320
1321         tbl->is_dup = lq_sta->is_dup;
1322         tbl->lq_type = LQ_SISO;
1323         tbl->action = 0;
1324         tbl->max_search = IWL_MAX_SEARCH;
1325         rate_mask = lq_sta->active_siso_rate;
1326
1327         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1328                 tbl->is_ht40 = 1;
1329         else
1330                 tbl->is_ht40 = 0;
1331
1332         if (is_green)
1333                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1334
1335         rs_set_expected_tpt_table(lq_sta, tbl);
1336         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1337
1338         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1339         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1340                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1341                              rate, rate_mask);
1342                 return -1;
1343         }
1344         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1345         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1346                      tbl->current_rate, is_green);
1347         return 0;
1348 }
1349
1350 /*
1351  * Try to switch to new modulation mode from legacy
1352  */
1353 static int rs_move_legacy_other(struct iwl_priv *priv,
1354                                 struct iwl_lq_sta *lq_sta,
1355                                 struct ieee80211_conf *conf,
1356                                 struct ieee80211_sta *sta,
1357                                 int index)
1358 {
1359         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1360         struct iwl_scale_tbl_info *search_tbl =
1361                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1362         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1363         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1364                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1365         u8 start_action = tbl->action;
1366         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1367         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1368         int ret = 0;
1369         u8 update_search_tbl_counter = 0;
1370
1371         if (!iwl_ht_enabled(priv))
1372                 /* stay in Legacy */
1373                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1374         else if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1375                    tbl->action > IWL_LEGACY_SWITCH_SISO)
1376                 tbl->action = IWL_LEGACY_SWITCH_SISO;
1377         for (; ;) {
1378                 lq_sta->action_counter++;
1379                 switch (tbl->action) {
1380                 case IWL_LEGACY_SWITCH_ANTENNA1:
1381                 case IWL_LEGACY_SWITCH_ANTENNA2:
1382                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1383
1384                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1385                                                         tx_chains_num <= 1) ||
1386                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1387                                                         tx_chains_num <= 2))
1388                                 break;
1389
1390                         /* Don't change antenna if success has been great */
1391                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1392                                 break;
1393
1394                         /* Set up search table to try other antenna */
1395                         memcpy(search_tbl, tbl, sz);
1396
1397                         if (rs_toggle_antenna(valid_tx_ant,
1398                                 &search_tbl->current_rate, search_tbl)) {
1399                                 update_search_tbl_counter = 1;
1400                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1401                                 goto out;
1402                         }
1403                         break;
1404                 case IWL_LEGACY_SWITCH_SISO:
1405                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1406
1407                         /* Set up search table to try SISO */
1408                         memcpy(search_tbl, tbl, sz);
1409                         search_tbl->is_SGI = 0;
1410                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1411                                                  search_tbl, index);
1412                         if (!ret) {
1413                                 lq_sta->action_counter = 0;
1414                                 goto out;
1415                         }
1416
1417                         break;
1418                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1419                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1420                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1421                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1422
1423                         /* Set up search table to try MIMO */
1424                         memcpy(search_tbl, tbl, sz);
1425                         search_tbl->is_SGI = 0;
1426
1427                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1428                                 search_tbl->ant_type = ANT_AB;
1429                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1430                                 search_tbl->ant_type = ANT_AC;
1431                         else
1432                                 search_tbl->ant_type = ANT_BC;
1433
1434                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1435                                 break;
1436
1437                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1438                                                  search_tbl, index);
1439                         if (!ret) {
1440                                 lq_sta->action_counter = 0;
1441                                 goto out;
1442                         }
1443                         break;
1444
1445                 case IWL_LEGACY_SWITCH_MIMO3_ABC:
1446                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO3\n");
1447
1448                         /* Set up search table to try MIMO3 */
1449                         memcpy(search_tbl, tbl, sz);
1450                         search_tbl->is_SGI = 0;
1451
1452                         search_tbl->ant_type = ANT_ABC;
1453
1454                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1455                                 break;
1456
1457                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1458                                                  search_tbl, index);
1459                         if (!ret) {
1460                                 lq_sta->action_counter = 0;
1461                                 goto out;
1462                         }
1463                         break;
1464                 }
1465                 tbl->action++;
1466                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1467                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1468
1469                 if (tbl->action == start_action)
1470                         break;
1471
1472         }
1473         search_tbl->lq_type = LQ_NONE;
1474         return 0;
1475
1476 out:
1477         lq_sta->search_better_tbl = 1;
1478         tbl->action++;
1479         if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1480                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1481         if (update_search_tbl_counter)
1482                 search_tbl->action = tbl->action;
1483         return 0;
1484
1485 }
1486
1487 /*
1488  * Try to switch to new modulation mode from SISO
1489  */
1490 static int rs_move_siso_to_other(struct iwl_priv *priv,
1491                                  struct iwl_lq_sta *lq_sta,
1492                                  struct ieee80211_conf *conf,
1493                                  struct ieee80211_sta *sta, int index)
1494 {
1495         u8 is_green = lq_sta->is_green;
1496         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1497         struct iwl_scale_tbl_info *search_tbl =
1498                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1499         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1500         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1501         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1502                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1503         u8 start_action = tbl->action;
1504         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1505         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1506         u8 update_search_tbl_counter = 0;
1507         int ret;
1508
1509         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1510             tbl->action > IWL_SISO_SWITCH_ANTENNA2) {
1511                 /* stay in SISO */
1512                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1513         }
1514         for (;;) {
1515                 lq_sta->action_counter++;
1516                 switch (tbl->action) {
1517                 case IWL_SISO_SWITCH_ANTENNA1:
1518                 case IWL_SISO_SWITCH_ANTENNA2:
1519                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1520
1521                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1522                                                         tx_chains_num <= 1) ||
1523                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1524                                                         tx_chains_num <= 2))
1525                                 break;
1526
1527                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1528                                 break;
1529
1530                         memcpy(search_tbl, tbl, sz);
1531                         if (rs_toggle_antenna(valid_tx_ant,
1532                                        &search_tbl->current_rate, search_tbl)) {
1533                                 update_search_tbl_counter = 1;
1534                                 goto out;
1535                         }
1536                         break;
1537                 case IWL_SISO_SWITCH_MIMO2_AB:
1538                 case IWL_SISO_SWITCH_MIMO2_AC:
1539                 case IWL_SISO_SWITCH_MIMO2_BC:
1540                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1541                         memcpy(search_tbl, tbl, sz);
1542                         search_tbl->is_SGI = 0;
1543
1544                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1545                                 search_tbl->ant_type = ANT_AB;
1546                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1547                                 search_tbl->ant_type = ANT_AC;
1548                         else
1549                                 search_tbl->ant_type = ANT_BC;
1550
1551                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1552                                 break;
1553
1554                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1555                                                  search_tbl, index);
1556                         if (!ret)
1557                                 goto out;
1558                         break;
1559                 case IWL_SISO_SWITCH_GI:
1560                         if (!tbl->is_ht40 && !(ht_cap->cap &
1561                                                 IEEE80211_HT_CAP_SGI_20))
1562                                 break;
1563                         if (tbl->is_ht40 && !(ht_cap->cap &
1564                                                 IEEE80211_HT_CAP_SGI_40))
1565                                 break;
1566
1567                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1568
1569                         memcpy(search_tbl, tbl, sz);
1570                         if (is_green) {
1571                                 if (!tbl->is_SGI)
1572                                         break;
1573                                 else
1574                                         IWL_ERR(priv,
1575                                                 "SGI was set in GF+SISO\n");
1576                         }
1577                         search_tbl->is_SGI = !tbl->is_SGI;
1578                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1579                         if (tbl->is_SGI) {
1580                                 s32 tpt = lq_sta->last_tpt / 100;
1581                                 if (tpt >= search_tbl->expected_tpt[index])
1582                                         break;
1583                         }
1584                         search_tbl->current_rate =
1585                                 rate_n_flags_from_tbl(priv, search_tbl,
1586                                                       index, is_green);
1587                         update_search_tbl_counter = 1;
1588                         goto out;
1589                 case IWL_SISO_SWITCH_MIMO3_ABC:
1590                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO3\n");
1591                         memcpy(search_tbl, tbl, sz);
1592                         search_tbl->is_SGI = 0;
1593                         search_tbl->ant_type = ANT_ABC;
1594
1595                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1596                                 break;
1597
1598                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1599                                                  search_tbl, index);
1600                         if (!ret)
1601                                 goto out;
1602                         break;
1603                 }
1604                 tbl->action++;
1605                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1606                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1607
1608                 if (tbl->action == start_action)
1609                         break;
1610         }
1611         search_tbl->lq_type = LQ_NONE;
1612         return 0;
1613
1614  out:
1615         lq_sta->search_better_tbl = 1;
1616         tbl->action++;
1617         if (tbl->action > IWL_SISO_SWITCH_MIMO3_ABC)
1618                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1619         if (update_search_tbl_counter)
1620                 search_tbl->action = tbl->action;
1621
1622         return 0;
1623 }
1624
1625 /*
1626  * Try to switch to new modulation mode from MIMO2
1627  */
1628 static int rs_move_mimo2_to_other(struct iwl_priv *priv,
1629                                  struct iwl_lq_sta *lq_sta,
1630                                  struct ieee80211_conf *conf,
1631                                  struct ieee80211_sta *sta, int index)
1632 {
1633         s8 is_green = lq_sta->is_green;
1634         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1635         struct iwl_scale_tbl_info *search_tbl =
1636                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1637         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1638         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1639         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1640                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1641         u8 start_action = tbl->action;
1642         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1643         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1644         u8 update_search_tbl_counter = 0;
1645         int ret;
1646
1647         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1648             (tbl->action < IWL_MIMO2_SWITCH_SISO_A ||
1649              tbl->action > IWL_MIMO2_SWITCH_SISO_C)) {
1650                 /* switch in SISO */
1651                 tbl->action = IWL_MIMO2_SWITCH_SISO_A;
1652         }
1653         for (;;) {
1654                 lq_sta->action_counter++;
1655                 switch (tbl->action) {
1656                 case IWL_MIMO2_SWITCH_ANTENNA1:
1657                 case IWL_MIMO2_SWITCH_ANTENNA2:
1658                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1659
1660                         if (tx_chains_num <= 2)
1661                                 break;
1662
1663                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1664                                 break;
1665
1666                         memcpy(search_tbl, tbl, sz);
1667                         if (rs_toggle_antenna(valid_tx_ant,
1668                                        &search_tbl->current_rate, search_tbl)) {
1669                                 update_search_tbl_counter = 1;
1670                                 goto out;
1671                         }
1672                         break;
1673                 case IWL_MIMO2_SWITCH_SISO_A:
1674                 case IWL_MIMO2_SWITCH_SISO_B:
1675                 case IWL_MIMO2_SWITCH_SISO_C:
1676                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1677
1678                         /* Set up new search table for SISO */
1679                         memcpy(search_tbl, tbl, sz);
1680
1681                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1682                                 search_tbl->ant_type = ANT_A;
1683                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1684                                 search_tbl->ant_type = ANT_B;
1685                         else
1686                                 search_tbl->ant_type = ANT_C;
1687
1688                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1689                                 break;
1690
1691                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1692                                                  search_tbl, index);
1693                         if (!ret)
1694                                 goto out;
1695
1696                         break;
1697
1698                 case IWL_MIMO2_SWITCH_GI:
1699                         if (!tbl->is_ht40 && !(ht_cap->cap &
1700                                                 IEEE80211_HT_CAP_SGI_20))
1701                                 break;
1702                         if (tbl->is_ht40 && !(ht_cap->cap &
1703                                                 IEEE80211_HT_CAP_SGI_40))
1704                                 break;
1705
1706                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1707
1708                         /* Set up new search table for MIMO2 */
1709                         memcpy(search_tbl, tbl, sz);
1710                         search_tbl->is_SGI = !tbl->is_SGI;
1711                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1712                         /*
1713                          * If active table already uses the fastest possible
1714                          * modulation (dual stream with short guard interval),
1715                          * and it's working well, there's no need to look
1716                          * for a better type of modulation!
1717                          */
1718                         if (tbl->is_SGI) {
1719                                 s32 tpt = lq_sta->last_tpt / 100;
1720                                 if (tpt >= search_tbl->expected_tpt[index])
1721                                         break;
1722                         }
1723                         search_tbl->current_rate =
1724                                 rate_n_flags_from_tbl(priv, search_tbl,
1725                                                       index, is_green);
1726                         update_search_tbl_counter = 1;
1727                         goto out;
1728
1729                 case IWL_MIMO2_SWITCH_MIMO3_ABC:
1730                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to MIMO3\n");
1731                         memcpy(search_tbl, tbl, sz);
1732                         search_tbl->is_SGI = 0;
1733                         search_tbl->ant_type = ANT_ABC;
1734
1735                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1736                                 break;
1737
1738                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1739                                                  search_tbl, index);
1740                         if (!ret)
1741                                 goto out;
1742
1743                         break;
1744                 }
1745                 tbl->action++;
1746                 if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1747                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1748
1749                 if (tbl->action == start_action)
1750                         break;
1751         }
1752         search_tbl->lq_type = LQ_NONE;
1753         return 0;
1754  out:
1755         lq_sta->search_better_tbl = 1;
1756         tbl->action++;
1757         if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1758                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1759         if (update_search_tbl_counter)
1760                 search_tbl->action = tbl->action;
1761
1762         return 0;
1763
1764 }
1765
1766 /*
1767  * Try to switch to new modulation mode from MIMO3
1768  */
1769 static int rs_move_mimo3_to_other(struct iwl_priv *priv,
1770                                  struct iwl_lq_sta *lq_sta,
1771                                  struct ieee80211_conf *conf,
1772                                  struct ieee80211_sta *sta, int index)
1773 {
1774         s8 is_green = lq_sta->is_green;
1775         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1776         struct iwl_scale_tbl_info *search_tbl =
1777                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1778         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1779         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1780         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1781                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1782         u8 start_action = tbl->action;
1783         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1784         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1785         int ret;
1786         u8 update_search_tbl_counter = 0;
1787
1788         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1789             (tbl->action < IWL_MIMO3_SWITCH_SISO_A ||
1790              tbl->action > IWL_MIMO3_SWITCH_SISO_C)) {
1791                 /* switch in SISO */
1792                 tbl->action = IWL_MIMO3_SWITCH_SISO_A;
1793         }
1794         for (;;) {
1795                 lq_sta->action_counter++;
1796                 switch (tbl->action) {
1797                 case IWL_MIMO3_SWITCH_ANTENNA1:
1798                 case IWL_MIMO3_SWITCH_ANTENNA2:
1799                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle Antennas\n");
1800
1801                         if (tx_chains_num <= 3)
1802                                 break;
1803
1804                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1805                                 break;
1806
1807                         memcpy(search_tbl, tbl, sz);
1808                         if (rs_toggle_antenna(valid_tx_ant,
1809                                        &search_tbl->current_rate, search_tbl))
1810                                 goto out;
1811                         break;
1812                 case IWL_MIMO3_SWITCH_SISO_A:
1813                 case IWL_MIMO3_SWITCH_SISO_B:
1814                 case IWL_MIMO3_SWITCH_SISO_C:
1815                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to SISO\n");
1816
1817                         /* Set up new search table for SISO */
1818                         memcpy(search_tbl, tbl, sz);
1819
1820                         if (tbl->action == IWL_MIMO3_SWITCH_SISO_A)
1821                                 search_tbl->ant_type = ANT_A;
1822                         else if (tbl->action == IWL_MIMO3_SWITCH_SISO_B)
1823                                 search_tbl->ant_type = ANT_B;
1824                         else
1825                                 search_tbl->ant_type = ANT_C;
1826
1827                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1828                                 break;
1829
1830                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1831                                                  search_tbl, index);
1832                         if (!ret)
1833                                 goto out;
1834
1835                         break;
1836
1837                 case IWL_MIMO3_SWITCH_MIMO2_AB:
1838                 case IWL_MIMO3_SWITCH_MIMO2_AC:
1839                 case IWL_MIMO3_SWITCH_MIMO2_BC:
1840                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to MIMO2\n");
1841
1842                         memcpy(search_tbl, tbl, sz);
1843                         search_tbl->is_SGI = 0;
1844                         if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AB)
1845                                 search_tbl->ant_type = ANT_AB;
1846                         else if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AC)
1847                                 search_tbl->ant_type = ANT_AC;
1848                         else
1849                                 search_tbl->ant_type = ANT_BC;
1850
1851                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1852                                 break;
1853
1854                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1855                                                  search_tbl, index);
1856                         if (!ret)
1857                                 goto out;
1858
1859                         break;
1860
1861                 case IWL_MIMO3_SWITCH_GI:
1862                         if (!tbl->is_ht40 && !(ht_cap->cap &
1863                                                 IEEE80211_HT_CAP_SGI_20))
1864                                 break;
1865                         if (tbl->is_ht40 && !(ht_cap->cap &
1866                                                 IEEE80211_HT_CAP_SGI_40))
1867                                 break;
1868
1869                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle SGI/NGI\n");
1870
1871                         /* Set up new search table for MIMO */
1872                         memcpy(search_tbl, tbl, sz);
1873                         search_tbl->is_SGI = !tbl->is_SGI;
1874                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1875                         /*
1876                          * If active table already uses the fastest possible
1877                          * modulation (dual stream with short guard interval),
1878                          * and it's working well, there's no need to look
1879                          * for a better type of modulation!
1880                          */
1881                         if (tbl->is_SGI) {
1882                                 s32 tpt = lq_sta->last_tpt / 100;
1883                                 if (tpt >= search_tbl->expected_tpt[index])
1884                                         break;
1885                         }
1886                         search_tbl->current_rate =
1887                                 rate_n_flags_from_tbl(priv, search_tbl,
1888                                                       index, is_green);
1889                         update_search_tbl_counter = 1;
1890                         goto out;
1891                 }
1892                 tbl->action++;
1893                 if (tbl->action > IWL_MIMO3_SWITCH_GI)
1894                         tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1895
1896                 if (tbl->action == start_action)
1897                         break;
1898         }
1899         search_tbl->lq_type = LQ_NONE;
1900         return 0;
1901  out:
1902         lq_sta->search_better_tbl = 1;
1903         tbl->action++;
1904         if (tbl->action > IWL_MIMO3_SWITCH_GI)
1905                 tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1906         if (update_search_tbl_counter)
1907                 search_tbl->action = tbl->action;
1908
1909         return 0;
1910
1911 }
1912
1913 /*
1914  * Check whether we should continue using same modulation mode, or
1915  * begin search for a new mode, based on:
1916  * 1) # tx successes or failures while using this mode
1917  * 2) # times calling this function
1918  * 3) elapsed time in this mode (not used, for now)
1919  */
1920 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1921 {
1922         struct iwl_scale_tbl_info *tbl;
1923         int i;
1924         int active_tbl;
1925         int flush_interval_passed = 0;
1926         struct iwl_priv *priv;
1927
1928         priv = lq_sta->drv;
1929         active_tbl = lq_sta->active_tbl;
1930
1931         tbl = &(lq_sta->lq_info[active_tbl]);
1932
1933         /* If we've been disallowing search, see if we should now allow it */
1934         if (lq_sta->stay_in_tbl) {
1935
1936                 /* Elapsed time using current modulation mode */
1937                 if (lq_sta->flush_timer)
1938                         flush_interval_passed =
1939                         time_after(jiffies,
1940                                         (unsigned long)(lq_sta->flush_timer +
1941                                         IWL_RATE_SCALE_FLUSH_INTVL));
1942
1943                 /*
1944                  * Check if we should allow search for new modulation mode.
1945                  * If many frames have failed or succeeded, or we've used
1946                  * this same modulation for a long time, allow search, and
1947                  * reset history stats that keep track of whether we should
1948                  * allow a new search.  Also (below) reset all bitmaps and
1949                  * stats in active history.
1950                  */
1951                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1952                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1953                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1954                      && (flush_interval_passed))) {
1955                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1956                                      lq_sta->total_failed,
1957                                      lq_sta->total_success,
1958                                      flush_interval_passed);
1959
1960                         /* Allow search for new mode */
1961                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1962                         lq_sta->total_failed = 0;
1963                         lq_sta->total_success = 0;
1964                         lq_sta->flush_timer = 0;
1965
1966                 /*
1967                  * Else if we've used this modulation mode enough repetitions
1968                  * (regardless of elapsed time or success/failure), reset
1969                  * history bitmaps and rate-specific stats for all rates in
1970                  * active table.
1971                  */
1972                 } else {
1973                         lq_sta->table_count++;
1974                         if (lq_sta->table_count >=
1975                             lq_sta->table_count_limit) {
1976                                 lq_sta->table_count = 0;
1977
1978                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
1979                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1980                                         rs_rate_scale_clear_window(
1981                                                 &(tbl->win[i]));
1982                         }
1983                 }
1984
1985                 /* If transitioning to allow "search", reset all history
1986                  * bitmaps and stats in active table (this will become the new
1987                  * "search" table). */
1988                 if (!lq_sta->stay_in_tbl) {
1989                         for (i = 0; i < IWL_RATE_COUNT; i++)
1990                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1991                 }
1992         }
1993 }
1994
1995 /*
1996  * setup rate table in uCode
1997  * return rate_n_flags as used in the table
1998  */
1999 static u32 rs_update_rate_tbl(struct iwl_priv *priv,
2000                                 struct iwl_lq_sta *lq_sta,
2001                                 struct iwl_scale_tbl_info *tbl,
2002                                 int index, u8 is_green)
2003 {
2004         u32 rate;
2005
2006         /* Update uCode's rate table. */
2007         rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2008         rs_fill_link_cmd(priv, lq_sta, rate);
2009         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2010
2011         return rate;
2012 }
2013
2014 /*
2015  * Do rate scaling and search for new modulation mode.
2016  */
2017 static void rs_rate_scale_perform(struct iwl_priv *priv,
2018                                   struct sk_buff *skb,
2019                                   struct ieee80211_sta *sta,
2020                                   struct iwl_lq_sta *lq_sta)
2021 {
2022         struct ieee80211_hw *hw = priv->hw;
2023         struct ieee80211_conf *conf = &hw->conf;
2024         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2025         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2026         int low = IWL_RATE_INVALID;
2027         int high = IWL_RATE_INVALID;
2028         int index;
2029         int i;
2030         struct iwl_rate_scale_data *window = NULL;
2031         int current_tpt = IWL_INVALID_VALUE;
2032         int low_tpt = IWL_INVALID_VALUE;
2033         int high_tpt = IWL_INVALID_VALUE;
2034         u32 fail_count;
2035         s8 scale_action = 0;
2036         u16 rate_mask;
2037         u8 update_lq = 0;
2038         struct iwl_scale_tbl_info *tbl, *tbl1;
2039         u16 rate_scale_index_msk = 0;
2040         u32 rate;
2041         u8 is_green = 0;
2042         u8 active_tbl = 0;
2043         u8 done_search = 0;
2044         u16 high_low;
2045         s32 sr;
2046         u8 tid = MAX_TID_COUNT;
2047         struct iwl_tid_data *tid_data;
2048
2049         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
2050
2051         /* Send management frames and NO_ACK data using lowest rate. */
2052         /* TODO: this could probably be improved.. */
2053         if (!ieee80211_is_data(hdr->frame_control) ||
2054             info->flags & IEEE80211_TX_CTL_NO_ACK)
2055                 return;
2056
2057         if (!sta || !lq_sta)
2058                 return;
2059
2060         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
2061
2062         tid = rs_tl_add_packet(lq_sta, hdr);
2063         if ((tid != MAX_TID_COUNT) && (lq_sta->tx_agg_tid_en & (1 << tid))) {
2064                 tid_data = &priv->stations[lq_sta->lq.sta_id].tid[tid];
2065                 if (tid_data->agg.state == IWL_AGG_OFF)
2066                         lq_sta->is_agg = 0;
2067                 else
2068                         lq_sta->is_agg = 1;
2069         } else
2070                 lq_sta->is_agg = 0;
2071
2072         /*
2073          * Select rate-scale / modulation-mode table to work with in
2074          * the rest of this function:  "search" if searching for better
2075          * modulation mode, or "active" if doing rate scaling within a mode.
2076          */
2077         if (!lq_sta->search_better_tbl)
2078                 active_tbl = lq_sta->active_tbl;
2079         else
2080                 active_tbl = 1 - lq_sta->active_tbl;
2081
2082         tbl = &(lq_sta->lq_info[active_tbl]);
2083         if (is_legacy(tbl->lq_type))
2084                 lq_sta->is_green = 0;
2085         else
2086                 lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2087         is_green = lq_sta->is_green;
2088
2089         /* current tx rate */
2090         index = lq_sta->last_txrate_idx;
2091
2092         IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
2093                        tbl->lq_type);
2094
2095         /* rates available for this association, and for modulation mode */
2096         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
2097
2098         IWL_DEBUG_RATE(priv, "mask 0x%04X \n", rate_mask);
2099
2100         /* mask with station rate restriction */
2101         if (is_legacy(tbl->lq_type)) {
2102                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
2103                         /* supp_rates has no CCK bits in A mode */
2104                         rate_scale_index_msk = (u16) (rate_mask &
2105                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
2106                 else
2107                         rate_scale_index_msk = (u16) (rate_mask &
2108                                                       lq_sta->supp_rates);
2109
2110         } else
2111                 rate_scale_index_msk = rate_mask;
2112
2113         if (!rate_scale_index_msk)
2114                 rate_scale_index_msk = rate_mask;
2115
2116         if (!((1 << index) & rate_scale_index_msk)) {
2117                 IWL_ERR(priv, "Current Rate is not valid\n");
2118                 if (lq_sta->search_better_tbl) {
2119                         /* revert to active table if search table is not valid*/
2120                         tbl->lq_type = LQ_NONE;
2121                         lq_sta->search_better_tbl = 0;
2122                         tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2123                         /* get "active" rate info */
2124                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2125                         rate = rs_update_rate_tbl(priv, lq_sta,
2126                                                   tbl, index, is_green);
2127                 }
2128                 return;
2129         }
2130
2131         /* Get expected throughput table and history window for current rate */
2132         if (!tbl->expected_tpt) {
2133                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
2134                 return;
2135         }
2136
2137         /* force user max rate if set by user */
2138         if ((lq_sta->max_rate_idx != -1) &&
2139             (lq_sta->max_rate_idx < index)) {
2140                 index = lq_sta->max_rate_idx;
2141                 update_lq = 1;
2142                 window = &(tbl->win[index]);
2143                 goto lq_update;
2144         }
2145
2146         window = &(tbl->win[index]);
2147
2148         /*
2149          * If there is not enough history to calculate actual average
2150          * throughput, keep analyzing results of more tx frames, without
2151          * changing rate or mode (bypass most of the rest of this function).
2152          * Set up new rate table in uCode only if old rate is not supported
2153          * in current association (use new rate found above).
2154          */
2155         fail_count = window->counter - window->success_counter;
2156         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
2157                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
2158                 IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
2159                                "for index %d\n",
2160                                window->success_counter, window->counter, index);
2161
2162                 /* Can't calculate this yet; not enough history */
2163                 window->average_tpt = IWL_INVALID_VALUE;
2164
2165                 /* Should we stay with this modulation mode,
2166                  * or search for a new one? */
2167                 rs_stay_in_table(lq_sta);
2168
2169                 goto out;
2170         }
2171         /* Else we have enough samples; calculate estimate of
2172          * actual average throughput */
2173
2174         /* Sanity-check TPT calculations */
2175         BUG_ON(window->average_tpt != ((window->success_ratio *
2176                         tbl->expected_tpt[index] + 64) / 128));
2177
2178         /* If we are searching for better modulation mode, check success. */
2179         if (lq_sta->search_better_tbl &&
2180             (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI)) {
2181                 /* If good success, continue using the "search" mode;
2182                  * no need to send new link quality command, since we're
2183                  * continuing to use the setup that we've been trying. */
2184                 if (window->average_tpt > lq_sta->last_tpt) {
2185
2186                         IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
2187                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2188                                         window->success_ratio,
2189                                         window->average_tpt,
2190                                         lq_sta->last_tpt);
2191
2192                         if (!is_legacy(tbl->lq_type))
2193                                 lq_sta->enable_counter = 1;
2194
2195                         /* Swap tables; "search" becomes "active" */
2196                         lq_sta->active_tbl = active_tbl;
2197                         current_tpt = window->average_tpt;
2198
2199                 /* Else poor success; go back to mode in "active" table */
2200                 } else {
2201
2202                         IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
2203                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2204                                         window->success_ratio,
2205                                         window->average_tpt,
2206                                         lq_sta->last_tpt);
2207
2208                         /* Nullify "search" table */
2209                         tbl->lq_type = LQ_NONE;
2210
2211                         /* Revert to "active" table */
2212                         active_tbl = lq_sta->active_tbl;
2213                         tbl = &(lq_sta->lq_info[active_tbl]);
2214
2215                         /* Revert to "active" rate and throughput info */
2216                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2217                         current_tpt = lq_sta->last_tpt;
2218
2219                         /* Need to set up a new rate table in uCode */
2220                         update_lq = 1;
2221                 }
2222
2223                 /* Either way, we've made a decision; modulation mode
2224                  * search is done, allow rate adjustment next time. */
2225                 lq_sta->search_better_tbl = 0;
2226                 done_search = 1;        /* Don't switch modes below! */
2227                 goto lq_update;
2228         }
2229
2230         /* (Else) not in search of better modulation mode, try for better
2231          * starting rate, while staying in this mode. */
2232         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
2233                                         tbl->lq_type);
2234         low = high_low & 0xff;
2235         high = (high_low >> 8) & 0xff;
2236
2237         /* If user set max rate, dont allow higher than user constrain */
2238         if ((lq_sta->max_rate_idx != -1) &&
2239             (lq_sta->max_rate_idx < high))
2240                 high = IWL_RATE_INVALID;
2241
2242         sr = window->success_ratio;
2243
2244         /* Collect measured throughputs for current and adjacent rates */
2245         current_tpt = window->average_tpt;
2246         if (low != IWL_RATE_INVALID)
2247                 low_tpt = tbl->win[low].average_tpt;
2248         if (high != IWL_RATE_INVALID)
2249                 high_tpt = tbl->win[high].average_tpt;
2250
2251         scale_action = 0;
2252
2253         /* Too many failures, decrease rate */
2254         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
2255                 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
2256                 scale_action = -1;
2257
2258         /* No throughput measured yet for adjacent rates; try increase. */
2259         } else if ((low_tpt == IWL_INVALID_VALUE) &&
2260                    (high_tpt == IWL_INVALID_VALUE)) {
2261
2262                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
2263                         scale_action = 1;
2264                 else if (low != IWL_RATE_INVALID)
2265                         scale_action = 0;
2266         }
2267
2268         /* Both adjacent throughputs are measured, but neither one has better
2269          * throughput; we're using the best rate, don't change it! */
2270         else if ((low_tpt != IWL_INVALID_VALUE) &&
2271                  (high_tpt != IWL_INVALID_VALUE) &&
2272                  (low_tpt < current_tpt) &&
2273                  (high_tpt < current_tpt))
2274                 scale_action = 0;
2275
2276         /* At least one adjacent rate's throughput is measured,
2277          * and may have better performance. */
2278         else {
2279                 /* Higher adjacent rate's throughput is measured */
2280                 if (high_tpt != IWL_INVALID_VALUE) {
2281                         /* Higher rate has better throughput */
2282                         if (high_tpt > current_tpt &&
2283                                         sr >= IWL_RATE_INCREASE_TH) {
2284                                 scale_action = 1;
2285                         } else {
2286                                 scale_action = 0;
2287                         }
2288
2289                 /* Lower adjacent rate's throughput is measured */
2290                 } else if (low_tpt != IWL_INVALID_VALUE) {
2291                         /* Lower rate has better throughput */
2292                         if (low_tpt > current_tpt) {
2293                                 IWL_DEBUG_RATE(priv,
2294                                     "decrease rate because of low tpt\n");
2295                                 scale_action = -1;
2296                         } else if (sr >= IWL_RATE_INCREASE_TH) {
2297                                 scale_action = 1;
2298                         }
2299                 }
2300         }
2301
2302         /* Sanity check; asked for decrease, but success rate or throughput
2303          * has been good at old rate.  Don't change it. */
2304         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
2305                     ((sr > IWL_RATE_HIGH_TH) ||
2306                      (current_tpt > (100 * tbl->expected_tpt[low]))))
2307                 scale_action = 0;
2308         if (!iwl_ht_enabled(priv) && !is_legacy(tbl->lq_type))
2309                 scale_action = -1;
2310         if (iwl_tx_ant_restriction(priv) != IWL_ANT_OK_MULTI &&
2311                 (is_mimo2(tbl->lq_type) || is_mimo3(tbl->lq_type)))
2312                 scale_action = -1;
2313         switch (scale_action) {
2314         case -1:
2315                 /* Decrease starting rate, update uCode's rate table */
2316                 if (low != IWL_RATE_INVALID) {
2317                         update_lq = 1;
2318                         index = low;
2319                 }
2320
2321                 break;
2322         case 1:
2323                 /* Increase starting rate, update uCode's rate table */
2324                 if (high != IWL_RATE_INVALID) {
2325                         update_lq = 1;
2326                         index = high;
2327                 }
2328
2329                 break;
2330         case 0:
2331                 /* No change */
2332         default:
2333                 break;
2334         }
2335
2336         IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
2337                     "high %d type %d\n",
2338                      index, scale_action, low, high, tbl->lq_type);
2339
2340 lq_update:
2341         /* Replace uCode's rate table for the destination station. */
2342         if (update_lq)
2343                 rate = rs_update_rate_tbl(priv, lq_sta,
2344                                           tbl, index, is_green);
2345
2346         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI) {
2347                 /* Should we stay with this modulation mode,
2348                  * or search for a new one? */
2349                 rs_stay_in_table(lq_sta);
2350         }
2351         /*
2352          * Search for new modulation mode if we're:
2353          * 1)  Not changing rates right now
2354          * 2)  Not just finishing up a search
2355          * 3)  Allowing a new search
2356          */
2357         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
2358                 /* Save current throughput to compare with "search" throughput*/
2359                 lq_sta->last_tpt = current_tpt;
2360
2361                 /* Select a new "search" modulation mode to try.
2362                  * If one is found, set up the new "search" table. */
2363                 if (is_legacy(tbl->lq_type))
2364                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
2365                 else if (is_siso(tbl->lq_type))
2366                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2367                 else if (is_mimo2(tbl->lq_type))
2368                         rs_move_mimo2_to_other(priv, lq_sta, conf, sta, index);
2369                 else
2370                         rs_move_mimo3_to_other(priv, lq_sta, conf, sta, index);
2371
2372                 /* If new "search" mode was selected, set up in uCode table */
2373                 if (lq_sta->search_better_tbl) {
2374                         /* Access the "search" table, clear its history. */
2375                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2376                         for (i = 0; i < IWL_RATE_COUNT; i++)
2377                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2378
2379                         /* Use new "search" start rate */
2380                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2381
2382                         IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
2383                                      tbl->current_rate, index);
2384                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
2385                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2386                 } else
2387                         done_search = 1;
2388         }
2389
2390         if (done_search && !lq_sta->stay_in_tbl) {
2391                 /* If the "active" (non-search) mode was legacy,
2392                  * and we've tried switching antennas,
2393                  * but we haven't been able to try HT modes (not available),
2394                  * stay with best antenna legacy modulation for a while
2395                  * before next round of mode comparisons. */
2396                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2397                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2398                     lq_sta->action_counter > tbl1->max_search) {
2399                         IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2400                         rs_set_stay_in_table(priv, 1, lq_sta);
2401                 }
2402
2403                 /* If we're in an HT mode, and all 3 mode switch actions
2404                  * have been tried and compared, stay in this best modulation
2405                  * mode for a while before next round of mode comparisons. */
2406                 if (lq_sta->enable_counter &&
2407                     (lq_sta->action_counter >= tbl1->max_search) &&
2408                     iwl_ht_enabled(priv)) {
2409                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2410                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2411                             (tid != MAX_TID_COUNT)) {
2412                                 tid_data =
2413                                    &priv->stations[lq_sta->lq.sta_id].tid[tid];
2414                                 if (tid_data->agg.state == IWL_AGG_OFF) {
2415                                         IWL_DEBUG_RATE(priv,
2416                                                        "try to aggregate tid %d\n",
2417                                                        tid);
2418                                         rs_tl_turn_on_agg(priv, tid,
2419                                                           lq_sta, sta);
2420                                 }
2421                         }
2422                         rs_set_stay_in_table(priv, 0, lq_sta);
2423                 }
2424         }
2425
2426 out:
2427         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2428         i = index;
2429         lq_sta->last_txrate_idx = i;
2430
2431         return;
2432 }
2433
2434
2435 static void rs_initialize_lq(struct iwl_priv *priv,
2436                              struct ieee80211_conf *conf,
2437                              struct ieee80211_sta *sta,
2438                              struct iwl_lq_sta *lq_sta)
2439 {
2440         struct iwl_scale_tbl_info *tbl;
2441         int rate_idx;
2442         int i;
2443         u32 rate;
2444         u8 use_green = rs_use_green(sta, &priv->current_ht_config);
2445         u8 active_tbl = 0;
2446         u8 valid_tx_ant;
2447
2448         if (!sta || !lq_sta)
2449                 goto out;
2450
2451         i = lq_sta->last_txrate_idx;
2452
2453         if ((lq_sta->lq.sta_id == 0xff) &&
2454             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2455                 goto out;
2456
2457         valid_tx_ant = priv->hw_params.valid_tx_ant;
2458
2459         if (!lq_sta->search_better_tbl)
2460                 active_tbl = lq_sta->active_tbl;
2461         else
2462                 active_tbl = 1 - lq_sta->active_tbl;
2463
2464         tbl = &(lq_sta->lq_info[active_tbl]);
2465
2466         if ((i < 0) || (i >= IWL_RATE_COUNT))
2467                 i = 0;
2468
2469         rate = iwl_rates[i].plcp;
2470         tbl->ant_type = first_antenna(valid_tx_ant);
2471         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2472
2473         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2474                 rate |= RATE_MCS_CCK_MSK;
2475
2476         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2477         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2478             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2479
2480         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2481         tbl->current_rate = rate;
2482         rs_set_expected_tpt_table(lq_sta, tbl);
2483         rs_fill_link_cmd(NULL, lq_sta, rate);
2484         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2485  out:
2486         return;
2487 }
2488
2489 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2490                         struct ieee80211_tx_rate_control *txrc)
2491 {
2492
2493         struct sk_buff *skb = txrc->skb;
2494         struct ieee80211_supported_band *sband = txrc->sband;
2495         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2496         struct ieee80211_conf *conf = &priv->hw->conf;
2497         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2498         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2499         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2500         struct iwl_lq_sta *lq_sta = priv_sta;
2501         int rate_idx;
2502
2503         IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2504
2505         /* Get max rate if user set max rate */
2506         if (lq_sta) {
2507                 lq_sta->max_rate_idx = txrc->max_rate_idx;
2508                 if ((sband->band == IEEE80211_BAND_5GHZ) &&
2509                     (lq_sta->max_rate_idx != -1))
2510                         lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2511                 if ((lq_sta->max_rate_idx < 0) ||
2512                     (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2513                         lq_sta->max_rate_idx = -1;
2514         }
2515
2516         /* Send management frames and NO_ACK data using lowest rate. */
2517         if (rate_control_send_low(sta, priv_sta, txrc))
2518                 return;
2519
2520         rate_idx  = lq_sta->last_txrate_idx;
2521
2522         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2523             !lq_sta->ibss_sta_added) {
2524                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2525
2526                 if (sta_id == IWL_INVALID_STATION) {
2527                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
2528                                        hdr->addr1);
2529                         sta_id = iwl_add_station(priv, hdr->addr1,
2530                                                 false, CMD_ASYNC, ht_cap);
2531                 }
2532                 if ((sta_id != IWL_INVALID_STATION)) {
2533                         lq_sta->lq.sta_id = sta_id;
2534                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2535                         lq_sta->ibss_sta_added = 1;
2536                         rs_initialize_lq(priv, conf, sta, lq_sta);
2537                 }
2538         }
2539
2540         if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2541                 rate_idx -= IWL_FIRST_OFDM_RATE;
2542                 /* 6M and 9M shared same MCS index */
2543                 rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2544                 if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2545                     IWL_RATE_MIMO3_6M_PLCP)
2546                         rate_idx = rate_idx + (2 * MCS_INDEX_PER_STREAM);
2547                 else if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2548                          IWL_RATE_MIMO2_6M_PLCP)
2549                         rate_idx = rate_idx + MCS_INDEX_PER_STREAM;
2550                 info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2551                 if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2552                         info->control.rates[0].flags |= IEEE80211_TX_RC_SHORT_GI;
2553                 if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2554                         info->control.rates[0].flags |= IEEE80211_TX_RC_DUP_DATA;
2555                 if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2556                         info->control.rates[0].flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
2557                 if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2558                         info->control.rates[0].flags |= IEEE80211_TX_RC_GREEN_FIELD;
2559         } else {
2560                 /* Check for invalid rates */
2561                 if ((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT_LEGACY) ||
2562                                 ((sband->band == IEEE80211_BAND_5GHZ) &&
2563                                  (rate_idx < IWL_FIRST_OFDM_RATE)))
2564                         rate_idx = rate_lowest_index(sband, sta);
2565                 /* On valid 5 GHz rate, adjust index */
2566                 else if (sband->band == IEEE80211_BAND_5GHZ)
2567                         rate_idx -= IWL_FIRST_OFDM_RATE;
2568                 info->control.rates[0].flags = 0;
2569         }
2570         info->control.rates[0].idx = rate_idx;
2571
2572 }
2573
2574 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2575                           gfp_t gfp)
2576 {
2577         struct iwl_lq_sta *lq_sta;
2578         struct iwl_priv *priv;
2579         int i, j;
2580
2581         priv = (struct iwl_priv *)priv_rate;
2582         IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2583
2584         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2585
2586         if (lq_sta == NULL)
2587                 return NULL;
2588         lq_sta->lq.sta_id = 0xff;
2589
2590
2591         for (j = 0; j < LQ_SIZE; j++)
2592                 for (i = 0; i < IWL_RATE_COUNT; i++)
2593                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2594
2595         return lq_sta;
2596 }
2597
2598 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2599                          struct ieee80211_sta *sta, void *priv_sta)
2600 {
2601         int i, j;
2602         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2603         struct ieee80211_conf *conf = &priv->hw->conf;
2604         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2605         struct iwl_lq_sta *lq_sta = priv_sta;
2606
2607         lq_sta->flush_timer = 0;
2608         lq_sta->supp_rates = sta->supp_rates[sband->band];
2609         for (j = 0; j < LQ_SIZE; j++)
2610                 for (i = 0; i < IWL_RATE_COUNT; i++)
2611                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2612
2613         IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init ***\n");
2614         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2615          * the lowest or the highest rate.. Could consider using RSSI from
2616          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2617          * after assoc.. */
2618
2619         lq_sta->ibss_sta_added = 0;
2620         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2621                 u8 sta_id = iwl_find_station(priv,
2622                                                                 sta->addr);
2623
2624                 /* for IBSS the call are from tasklet */
2625                 IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2626
2627                 if (sta_id == IWL_INVALID_STATION) {
2628                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2629                         sta_id = iwl_add_station(priv, sta->addr, false,
2630                                                 CMD_ASYNC, ht_cap);
2631                 }
2632                 if ((sta_id != IWL_INVALID_STATION)) {
2633                         lq_sta->lq.sta_id = sta_id;
2634                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2635                 }
2636                 /* FIXME: this is w/a remove it later */
2637                 priv->assoc_station_added = 1;
2638         }
2639
2640         lq_sta->is_dup = 0;
2641         lq_sta->max_rate_idx = -1;
2642         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2643         lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2644         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2645         lq_sta->active_rate_basic = priv->active_rate_basic;
2646         lq_sta->band = priv->band;
2647         /*
2648          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2649          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2650          */
2651         lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
2652         lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
2653         lq_sta->active_siso_rate &= ~((u16)0x2);
2654         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2655
2656         /* Same here */
2657         lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
2658         lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
2659         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2660         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2661
2662         lq_sta->active_mimo3_rate = ht_cap->mcs.rx_mask[2] << 1;
2663         lq_sta->active_mimo3_rate |= ht_cap->mcs.rx_mask[2] & 0x1;
2664         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2665         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2666
2667         IWL_DEBUG_RATE(priv, "SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2668                      lq_sta->active_siso_rate,
2669                      lq_sta->active_mimo2_rate,
2670                      lq_sta->active_mimo3_rate);
2671
2672         /* These values will be overridden later */
2673         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2674         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2675
2676         /* as default allow aggregation for all tids */
2677         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2678         lq_sta->drv = priv;
2679
2680         /* Set last_txrate_idx to lowest rate */
2681         lq_sta->last_txrate_idx = rate_lowest_index(sband, sta);
2682         if (sband->band == IEEE80211_BAND_5GHZ)
2683                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2684         lq_sta->is_agg = 0;
2685
2686         rs_initialize_lq(priv, conf, sta, lq_sta);
2687 }
2688
2689 static void rs_fill_link_cmd(struct iwl_priv *priv,
2690                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2691 {
2692         struct iwl_scale_tbl_info tbl_type;
2693         int index = 0;
2694         int rate_idx;
2695         int repeat_rate = 0;
2696         u8 ant_toggle_cnt = 0;
2697         u8 use_ht_possible = 1;
2698         u8 valid_tx_ant = 0;
2699         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2700
2701         /* Override starting rate (index 0) if needed for debug purposes */
2702         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2703
2704         /* Interpret new_rate (rate_n_flags) */
2705         memset(&tbl_type, 0, sizeof(tbl_type));
2706         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2707                                   &tbl_type, &rate_idx);
2708
2709         /* How many times should we repeat the initial rate? */
2710         if (is_legacy(tbl_type.lq_type)) {
2711                 ant_toggle_cnt = 1;
2712                 repeat_rate = IWL_NUMBER_TRY;
2713         } else {
2714                 repeat_rate = IWL_HT_NUMBER_TRY;
2715         }
2716
2717         lq_cmd->general_params.mimo_delimiter =
2718                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2719
2720         /* Fill 1st table entry (index 0) */
2721         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2722
2723         if (num_of_ant(tbl_type.ant_type) == 1) {
2724                 lq_cmd->general_params.single_stream_ant_msk =
2725                                                 tbl_type.ant_type;
2726         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2727                 lq_cmd->general_params.dual_stream_ant_msk =
2728                                                 tbl_type.ant_type;
2729         } /* otherwise we don't modify the existing value */
2730
2731         index++;
2732         repeat_rate--;
2733
2734         if (priv)
2735                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2736
2737         /* Fill rest of rate table */
2738         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2739                 /* Repeat initial/next rate.
2740                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2741                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2742                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2743                         if (is_legacy(tbl_type.lq_type)) {
2744                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2745                                         ant_toggle_cnt++;
2746                                 else if (priv &&
2747                                          rs_toggle_antenna(valid_tx_ant,
2748                                                         &new_rate, &tbl_type))
2749                                         ant_toggle_cnt = 1;
2750 }
2751
2752                         /* Override next rate if needed for debug purposes */
2753                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2754
2755                         /* Fill next table entry */
2756                         lq_cmd->rs_table[index].rate_n_flags =
2757                                         cpu_to_le32(new_rate);
2758                         repeat_rate--;
2759                         index++;
2760                 }
2761
2762                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2763                                                 &rate_idx);
2764
2765                 /* Indicate to uCode which entries might be MIMO.
2766                  * If initial rate was MIMO, this will finally end up
2767                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2768                 if (is_mimo(tbl_type.lq_type))
2769                         lq_cmd->general_params.mimo_delimiter = index;
2770
2771                 /* Get next rate */
2772                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2773                                              use_ht_possible);
2774
2775                 /* How many times should we repeat the next rate? */
2776                 if (is_legacy(tbl_type.lq_type)) {
2777                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2778                                 ant_toggle_cnt++;
2779                         else if (priv &&
2780                                  rs_toggle_antenna(valid_tx_ant,
2781                                                    &new_rate, &tbl_type))
2782                                 ant_toggle_cnt = 1;
2783
2784                         repeat_rate = IWL_NUMBER_TRY;
2785                 } else {
2786                         repeat_rate = IWL_HT_NUMBER_TRY;
2787                 }
2788
2789                 /* Don't allow HT rates after next pass.
2790                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2791                 use_ht_possible = 0;
2792
2793                 /* Override next rate if needed for debug purposes */
2794                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2795
2796                 /* Fill next table entry */
2797                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2798
2799                 index++;
2800                 repeat_rate--;
2801         }
2802
2803         lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_MAX;
2804         lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2805         lq_cmd->agg_params.agg_time_limit =
2806                 cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2807 }
2808
2809 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2810 {
2811         return hw->priv;
2812 }
2813 /* rate scale requires free function to be implemented */
2814 static void rs_free(void *priv_rate)
2815 {
2816         return;
2817 }
2818
2819 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2820                         void *priv_sta)
2821 {
2822         struct iwl_lq_sta *lq_sta = priv_sta;
2823         struct iwl_priv *priv __maybe_unused = priv_r;
2824
2825         IWL_DEBUG_RATE(priv, "enter\n");
2826         kfree(lq_sta);
2827         IWL_DEBUG_RATE(priv, "leave\n");
2828 }
2829
2830
2831 #ifdef CONFIG_MAC80211_DEBUGFS
2832 static int open_file_generic(struct inode *inode, struct file *file)
2833 {
2834         file->private_data = inode->i_private;
2835         return 0;
2836 }
2837 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2838                              u32 *rate_n_flags, int index)
2839 {
2840         struct iwl_priv *priv;
2841         u8 valid_tx_ant;
2842         u8 ant_sel_tx;
2843
2844         priv = lq_sta->drv;
2845         valid_tx_ant = priv->hw_params.valid_tx_ant;
2846         if (lq_sta->dbg_fixed_rate) {
2847                 ant_sel_tx =
2848                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2849                   >> RATE_MCS_ANT_POS);
2850                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2851                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2852                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2853                 } else {
2854                         lq_sta->dbg_fixed_rate = 0;
2855                         IWL_ERR(priv,
2856                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2857                             ant_sel_tx, valid_tx_ant);
2858                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2859                 }
2860         } else {
2861                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2862         }
2863 }
2864
2865 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2866                         const char __user *user_buf, size_t count, loff_t *ppos)
2867 {
2868         struct iwl_lq_sta *lq_sta = file->private_data;
2869         struct iwl_priv *priv;
2870         char buf[64];
2871         int buf_size;
2872         u32 parsed_rate;
2873
2874         priv = lq_sta->drv;
2875         memset(buf, 0, sizeof(buf));
2876         buf_size = min(count, sizeof(buf) -  1);
2877         if (copy_from_user(buf, user_buf, buf_size))
2878                 return -EFAULT;
2879
2880         if (sscanf(buf, "%x", &parsed_rate) == 1)
2881                 lq_sta->dbg_fixed_rate = parsed_rate;
2882         else
2883                 lq_sta->dbg_fixed_rate = 0;
2884
2885         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2886         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2887         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2888         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2889
2890         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2891                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2892
2893         if (lq_sta->dbg_fixed_rate) {
2894                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2895                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2896         }
2897
2898         return count;
2899 }
2900
2901 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2902                         char __user *user_buf, size_t count, loff_t *ppos)
2903 {
2904         char *buff;
2905         int desc = 0;
2906         int i = 0;
2907         int index = 0;
2908         ssize_t ret;
2909
2910         struct iwl_lq_sta *lq_sta = file->private_data;
2911         struct iwl_priv *priv;
2912         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2913
2914         priv = lq_sta->drv;
2915         buff = kmalloc(1024, GFP_KERNEL);
2916         if (!buff)
2917                 return -ENOMEM;
2918
2919         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2920         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2921                         lq_sta->total_failed, lq_sta->total_success,
2922                         lq_sta->active_legacy_rate);
2923         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2924                         lq_sta->dbg_fixed_rate);
2925         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2926             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2927             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2928             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2929         desc += sprintf(buff+desc, "lq type %s\n",
2930            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2931         if (is_Ht(tbl->lq_type)) {
2932                 desc += sprintf(buff+desc, " %s",
2933                    (is_siso(tbl->lq_type)) ? "SISO" :
2934                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2935                    desc += sprintf(buff+desc, " %s",
2936                    (tbl->is_ht40) ? "40MHz" : "20MHz");
2937                    desc += sprintf(buff+desc, " %s %s %s\n", (tbl->is_SGI) ? "SGI" : "",
2938                    (lq_sta->is_green) ? "GF enabled" : "",
2939                    (lq_sta->is_agg) ? "AGG on" : "");
2940         }
2941         desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2942                 lq_sta->last_rate_n_flags);
2943         desc += sprintf(buff+desc, "general:"
2944                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2945                 lq_sta->lq.general_params.flags,
2946                 lq_sta->lq.general_params.mimo_delimiter,
2947                 lq_sta->lq.general_params.single_stream_ant_msk,
2948                 lq_sta->lq.general_params.dual_stream_ant_msk);
2949
2950         desc += sprintf(buff+desc, "agg:"
2951                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2952                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2953                         lq_sta->lq.agg_params.agg_dis_start_th,
2954                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2955
2956         desc += sprintf(buff+desc,
2957                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2958                         lq_sta->lq.general_params.start_rate_index[0],
2959                         lq_sta->lq.general_params.start_rate_index[1],
2960                         lq_sta->lq.general_params.start_rate_index[2],
2961                         lq_sta->lq.general_params.start_rate_index[3]);
2962
2963         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2964                 index = iwl_hwrate_to_plcp_idx(
2965                         le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2966                 if (is_legacy(tbl->lq_type)) {
2967                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2968                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2969                                 iwl_rate_mcs[index].mbps);
2970                 } else {
2971                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps (%s)\n",
2972                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2973                                 iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
2974                 }
2975         }
2976
2977         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2978         kfree(buff);
2979         return ret;
2980 }
2981
2982 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2983         .write = rs_sta_dbgfs_scale_table_write,
2984         .read = rs_sta_dbgfs_scale_table_read,
2985         .open = open_file_generic,
2986 };
2987 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2988                         char __user *user_buf, size_t count, loff_t *ppos)
2989 {
2990         char *buff;
2991         int desc = 0;
2992         int i, j;
2993         ssize_t ret;
2994
2995         struct iwl_lq_sta *lq_sta = file->private_data;
2996
2997         buff = kmalloc(1024, GFP_KERNEL);
2998         if (!buff)
2999                 return -ENOMEM;
3000
3001         for (i = 0; i < LQ_SIZE; i++) {
3002                 desc += sprintf(buff+desc,
3003                                 "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
3004                                 "rate=0x%X\n",
3005                                 lq_sta->active_tbl == i ? "*" : "x",
3006                                 lq_sta->lq_info[i].lq_type,
3007                                 lq_sta->lq_info[i].is_SGI,
3008                                 lq_sta->lq_info[i].is_ht40,
3009                                 lq_sta->lq_info[i].is_dup,
3010                                 lq_sta->is_green,
3011                                 lq_sta->lq_info[i].current_rate);
3012                 for (j = 0; j < IWL_RATE_COUNT; j++) {
3013                         desc += sprintf(buff+desc,
3014                                 "counter=%d success=%d %%=%d\n",
3015                                 lq_sta->lq_info[i].win[j].counter,
3016                                 lq_sta->lq_info[i].win[j].success_counter,
3017                                 lq_sta->lq_info[i].win[j].success_ratio);
3018                 }
3019         }
3020         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3021         kfree(buff);
3022         return ret;
3023 }
3024
3025 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
3026         .read = rs_sta_dbgfs_stats_table_read,
3027         .open = open_file_generic,
3028 };
3029
3030 static ssize_t rs_sta_dbgfs_rate_scale_data_read(struct file *file,
3031                         char __user *user_buf, size_t count, loff_t *ppos)
3032 {
3033         char buff[120];
3034         int desc = 0;
3035         ssize_t ret;
3036
3037         struct iwl_lq_sta *lq_sta = file->private_data;
3038         struct iwl_priv *priv;
3039         struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
3040
3041         priv = lq_sta->drv;
3042
3043         if (is_Ht(tbl->lq_type))
3044                 desc += sprintf(buff+desc,
3045                                 "Bit Rate= %d Mb/s\n",
3046                                 tbl->expected_tpt[lq_sta->last_txrate_idx]);
3047         else
3048                 desc += sprintf(buff+desc,
3049                                 "Bit Rate= %d Mb/s\n",
3050                                 iwl_rates[lq_sta->last_txrate_idx].ieee >> 1);
3051         desc += sprintf(buff+desc,
3052                         "Signal Level= %d dBm\tNoise Level= %d dBm\n",
3053                         priv->last_rx_rssi, priv->last_rx_noise);
3054         desc += sprintf(buff+desc,
3055                         "Tsf= 0x%llx\tBeacon time= 0x%08X\n",
3056                         priv->last_tsf, priv->last_beacon_time);
3057
3058         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3059         return ret;
3060 }
3061
3062 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
3063         .read = rs_sta_dbgfs_rate_scale_data_read,
3064         .open = open_file_generic,
3065 };
3066
3067 static void rs_add_debugfs(void *priv, void *priv_sta,
3068                                         struct dentry *dir)
3069 {
3070         struct iwl_lq_sta *lq_sta = priv_sta;
3071         lq_sta->rs_sta_dbgfs_scale_table_file =
3072                 debugfs_create_file("rate_scale_table", 0600, dir,
3073                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
3074         lq_sta->rs_sta_dbgfs_stats_table_file =
3075                 debugfs_create_file("rate_stats_table", 0600, dir,
3076                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
3077         lq_sta->rs_sta_dbgfs_rate_scale_data_file =
3078                 debugfs_create_file("rate_scale_data", 0600, dir,
3079                         lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
3080         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
3081                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
3082                 &lq_sta->tx_agg_tid_en);
3083
3084 }
3085
3086 static void rs_remove_debugfs(void *priv, void *priv_sta)
3087 {
3088         struct iwl_lq_sta *lq_sta = priv_sta;
3089         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
3090         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
3091         debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
3092         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
3093 }
3094 #endif
3095
3096 static struct rate_control_ops rs_ops = {
3097         .module = NULL,
3098         .name = RS_NAME,
3099         .tx_status = rs_tx_status,
3100         .get_rate = rs_get_rate,
3101         .rate_init = rs_rate_init,
3102         .alloc = rs_alloc,
3103         .free = rs_free,
3104         .alloc_sta = rs_alloc_sta,
3105         .free_sta = rs_free_sta,
3106 #ifdef CONFIG_MAC80211_DEBUGFS
3107         .add_sta_debugfs = rs_add_debugfs,
3108         .remove_sta_debugfs = rs_remove_debugfs,
3109 #endif
3110 };
3111
3112 int iwlagn_rate_control_register(void)
3113 {
3114         return ieee80211_rate_control_register(&rs_ops);
3115 }
3116
3117 void iwlagn_rate_control_unregister(void)
3118 {
3119         ieee80211_rate_control_unregister(&rs_ops);
3120 }
3121