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 };
 175
 176 static void rs_rate_scale_perform(struct iwl_priv *priv,
 177                                    struct sk_buff *skb,
 178                                    struct ieee80211_sta *sta,
 179                                    struct iwl_lq_sta *lq_sta);
 180 static void rs_fill_link_cmd(struct iwl_priv *priv,
 181                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
 182
 183
 184 #ifdef CONFIG_MAC80211_DEBUGFS
 185 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 186                              u32 *rate_n_flags, int index);
 187 #else
 188 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 189                              u32 *rate_n_flags, int index)
 190 {}
 191 #endif
 192
 193 /*
 194  * Expected throughput metrics for following rates:
 195  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
 196  * "G" is the only table that supports CCK (the first 4 rates).
 197  */
 198
 199 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
 200         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
 201 };
 202
 203 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
 204         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
 205 };
 206
 207 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
 208         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
 209 };
 210
 211 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
 212         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
 213 };
 214
 215 static s32 expected_tpt_mimo2_20MHz[IWL_RATE_COUNT] = {
 216         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
 217 };
 218
 219 static s32 expected_tpt_mimo2_20MHzSGI[IWL_RATE_COUNT] = {
 220         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
 221 };
 222
 223 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
 224         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
 225 };
 226
 227 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
 228         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
 229 };
 230
 231 static s32 expected_tpt_mimo2_40MHz[IWL_RATE_COUNT] = {
 232         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
 233 };
 234
 235 static s32 expected_tpt_mimo2_40MHzSGI[IWL_RATE_COUNT] = {
 236         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
 237 };
 238
 239 /* Expected throughput metric MIMO3 */
 240 static s32 expected_tpt_mimo3_20MHz[IWL_RATE_COUNT] = {
 241         0, 0, 0, 0, 99, 99, 153, 186, 208, 239, 256, 263, 268
 242 };
 243
 244 static s32 expected_tpt_mimo3_20MHzSGI[IWL_RATE_COUNT] = {
 245         0, 0, 0, 0, 106, 106, 162, 194, 215, 246, 262, 268, 273
 246 };
 247
 248 static s32 expected_tpt_mimo3_40MHz[IWL_RATE_COUNT] = {
 249         0, 0, 0, 0, 152, 152, 211, 239, 255, 279, 290, 294, 297
 250 };
 251
 252 static s32 expected_tpt_mimo3_40MHzSGI[IWL_RATE_COUNT] = {
 253         0, 0, 0, 0, 160, 160, 219, 245, 261, 284, 294, 297, 300
 254 };
 255
 256 /* mbps, mcs */
 257 const static struct iwl_rate_mcs_info iwl_rate_mcs[IWL_RATE_COUNT] = {
 258   {"1", ""},
 259   {"2", ""},
 260   {"5.5", ""},
 261   {"11", ""},
 262   {"6", "BPSK 1/2"},
 263   {"9", "BPSK 1/2"},
 264   {"12", "QPSK 1/2"},
 265   {"18", "QPSK 3/4"},
 266   {"24", "16QAM 1/2"},
 267   {"36", "16QAM 3/4"},
 268   {"48", "64QAM 2/3"},
 269   {"54", "64QAM 3/4"},
 270   {"60", "64QAM 5/6"}
 271 };
 272
 273 #define MCS_INDEX_PER_STREAM    (8)
 274
 275 static inline u8 rs_extract_rate(u32 rate_n_flags)
 276 {
 277         return (u8)(rate_n_flags & 0xFF);
 278 }
 279
 280 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
 281 {
 282         window->data = 0;
 283         window->success_counter = 0;
 284         window->success_ratio = IWL_INVALID_VALUE;
 285         window->counter = 0;
 286         window->average_tpt = IWL_INVALID_VALUE;
 287         window->stamp = 0;
 288 }
 289
 290 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
 291 {
 292         return (ant_type & valid_antenna) == ant_type;
 293 }
 294
 295 /*
 296  *      removes the old data from the statistics. All data that is older than
 297  *      TID_MAX_TIME_DIFF, will be deleted.
 298  */
 299 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
 300 {
 301         /* The oldest age we want to keep */
 302         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
 303
 304         while (tl->queue_count &&
 305                (tl->time_stamp < oldest_time)) {
 306                 tl->total -= tl->packet_count[tl->head];
 307                 tl->packet_count[tl->head] = 0;
 308                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
 309                 tl->queue_count--;
 310                 tl->head++;
 311                 if (tl->head >= TID_QUEUE_MAX_SIZE)
 312                         tl->head = 0;
 313         }
 314 }
 315
 316 /*
 317  *      increment traffic load value for tid and also remove
 318  *      any old values if passed the certain time period
 319  */
 320 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
 321                            struct ieee80211_hdr *hdr)
 322 {
 323         u32 curr_time = jiffies_to_msecs(jiffies);
 324         u32 time_diff;
 325         s32 index;
 326         struct iwl_traffic_load *tl = NULL;
 327         u8 tid;
 328
 329         if (ieee80211_is_data_qos(hdr->frame_control)) {
 330                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 331                 tid = qc[0] & 0xf;
 332         } else
 333                 return MAX_TID_COUNT;
 334
 335         if (unlikely(tid >= TID_MAX_LOAD_COUNT))
 336                 return MAX_TID_COUNT;
 337
 338         tl = &lq_data->load[tid];
 339
 340         curr_time -= curr_time % TID_ROUND_VALUE;
 341
 342         /* Happens only for the first packet. Initialize the data */
 343         if (!(tl->queue_count)) {
 344                 tl->total = 1;
 345                 tl->time_stamp = curr_time;
 346                 tl->queue_count = 1;
 347                 tl->head = 0;
 348                 tl->packet_count[0] = 1;
 349                 return MAX_TID_COUNT;
 350         }
 351
 352         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 353         index = time_diff / TID_QUEUE_CELL_SPACING;
 354
 355         /* The history is too long: remove data that is older than */
 356         /* TID_MAX_TIME_DIFF */
 357         if (index >= TID_QUEUE_MAX_SIZE)
 358                 rs_tl_rm_old_stats(tl, curr_time);
 359
 360         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
 361         tl->packet_count[index] = tl->packet_count[index] + 1;
 362         tl->total = tl->total + 1;
 363
 364         if ((index + 1) > tl->queue_count)
 365                 tl->queue_count = index + 1;
 366
 367         return tid;
 368 }
 369
 370 /*
 371         get the traffic load value for tid
 372 */
 373 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
 374 {
 375         u32 curr_time = jiffies_to_msecs(jiffies);
 376         u32 time_diff;
 377         s32 index;
 378         struct iwl_traffic_load *tl = NULL;
 379
 380         if (tid >= TID_MAX_LOAD_COUNT)
 381                 return 0;
 382
 383         tl = &(lq_data->load[tid]);
 384
 385         curr_time -= curr_time % TID_ROUND_VALUE;
 386
 387         if (!(tl->queue_count))
 388                 return 0;
 389
 390         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 391         index = time_diff / TID_QUEUE_CELL_SPACING;
 392
 393         /* The history is too long: remove data that is older than */
 394         /* TID_MAX_TIME_DIFF */
 395         if (index >= TID_QUEUE_MAX_SIZE)
 396                 rs_tl_rm_old_stats(tl, curr_time);
 397
 398         return tl->total;
 399 }
 400
 401 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
 402                                       struct iwl_lq_sta *lq_data, u8 tid,
 403                                       struct ieee80211_sta *sta)
 404 {
 405         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
 406                 IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n",
 407                                 sta->addr, tid);
 408                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
 409         }
 410 }
 411
 412 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
 413                               struct iwl_lq_sta *lq_data,
 414                               struct ieee80211_sta *sta)
 415 {
 416         if ((tid < TID_MAX_LOAD_COUNT))
 417                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 418         else if (tid == IWL_AGG_ALL_TID)
 419                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
 420                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 421 }
 422
 423 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
 424 {
 425         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
 426                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
 427                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
 428 }
 429
 430 /**
 431  * rs_collect_tx_data - Update the success/failure sliding window
 432  *
 433  * We keep a sliding window of the last 62 packets transmitted
 434  * at this rate.  window->data contains the bitmask of successful
 435  * packets.
 436  */
 437 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
 438                               int scale_index, s32 tpt, int retries,
 439                               int successes)
 440 {
 441         struct iwl_rate_scale_data *window = NULL;
 442         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 443         s32 fail_count;
 444
 445         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 446                 return -EINVAL;
 447
 448         /* Select data for current tx bit rate */
 449         window = &(windows[scale_index]);
 450
 451         /*
 452          * Keep track of only the latest 62 tx frame attempts in this rate's
 453          * history window; anything older isn't really relevant any more.
 454          * If we have filled up the sliding window, drop the oldest attempt;
 455          * if the oldest attempt (highest bit in bitmap) shows "success",
 456          * subtract "1" from the success counter (this is the main reason
 457          * we keep these bitmaps!).
 458          */
 459         while (retries > 0) {
 460                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 461
 462                         /* remove earliest */
 463                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 464
 465                         if (window->data & mask) {
 466                                 window->data &= ~mask;
 467                                 window->success_counter--;
 468                         }
 469                 }
 470
 471                 /* Increment frames-attempted counter */
 472                 window->counter++;
 473
 474                 /* Shift bitmap by one frame (throw away oldest history),
 475                  * OR in "1", and increment "success" if this
 476                  * frame was successful. */
 477                 window->data <<= 1;
 478                 if (successes > 0) {
 479                         window->success_counter++;
 480                         window->data |= 0x1;
 481                         successes--;
 482                 }
 483
 484                 retries--;
 485         }
 486
 487         /* Calculate current success ratio, avoid divide-by-0! */
 488         if (window->counter > 0)
 489                 window->success_ratio = 128 * (100 * window->success_counter)
 490                                         / window->counter;
 491         else
 492                 window->success_ratio = IWL_INVALID_VALUE;
 493
 494         fail_count = window->counter - window->success_counter;
 495
 496         /* Calculate average throughput, if we have enough history. */
 497         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 498             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 499                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 500         else
 501                 window->average_tpt = IWL_INVALID_VALUE;
 502
 503         /* Tag this window as having been updated */
 504         window->stamp = jiffies;
 505
 506         return 0;
 507 }
 508
 509 /*
 510  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 511  */
 512 /* FIXME:RS:remove this function and put the flags statically in the table */
 513 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 514                                  struct iwl_scale_tbl_info *tbl,
 515                                  int index, u8 use_green)
 516 {
 517         u32 rate_n_flags = 0;
 518
 519         if (is_legacy(tbl->lq_type)) {
 520                 rate_n_flags = iwl_rates[index].plcp;
 521                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 522                         rate_n_flags |= RATE_MCS_CCK_MSK;
 523
 524         } else if (is_Ht(tbl->lq_type)) {
 525                 if (index > IWL_LAST_OFDM_RATE) {
 526                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 527                         index = IWL_LAST_OFDM_RATE;
 528                 }
 529                 rate_n_flags = RATE_MCS_HT_MSK;
 530
 531                 if (is_siso(tbl->lq_type))
 532                         rate_n_flags |= iwl_rates[index].plcp_siso;
 533                 else if (is_mimo2(tbl->lq_type))
 534                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 535                 else
 536                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 537         } else {
 538                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 539         }
 540
 541         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 542                                                      RATE_MCS_ANT_ABC_MSK);
 543
 544         if (is_Ht(tbl->lq_type)) {
 545                 if (tbl->is_ht40) {
 546                         if (tbl->is_dup)
 547                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 548                         else
 549                                 rate_n_flags |= RATE_MCS_HT40_MSK;
 550                 }
 551                 if (tbl->is_SGI)
 552                         rate_n_flags |= RATE_MCS_SGI_MSK;
 553
 554                 if (use_green) {
 555                         rate_n_flags |= RATE_MCS_GF_MSK;
 556                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 557                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 558                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 559                         }
 560                 }
 561         }
 562         return rate_n_flags;
 563 }
 564
 565 /*
 566  * Interpret uCode API's rate_n_flags format,
 567  * fill "search" or "active" tx mode table.
 568  */
 569 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 570                                     enum ieee80211_band band,
 571                                     struct iwl_scale_tbl_info *tbl,
 572                                     int *rate_idx)
 573 {
 574         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 575         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 576         u8 mcs;
 577
 578         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 579
 580         if (*rate_idx  == IWL_RATE_INVALID) {
 581                 *rate_idx = -1;
 582                 return -EINVAL;
 583         }
 584         tbl->is_SGI = 0;        /* default legacy setup */
 585         tbl->is_ht40 = 0;
 586         tbl->is_dup = 0;
 587         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 588         tbl->lq_type = LQ_NONE;
 589         tbl->max_search = IWL_MAX_SEARCH;
 590
 591         /* legacy rate format */
 592         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 593                 if (num_of_ant == 1) {
 594                         if (band == IEEE80211_BAND_5GHZ)
 595                                 tbl->lq_type = LQ_A;
 596                         else
 597                                 tbl->lq_type = LQ_G;
 598                 }
 599         /* HT rate format */
 600         } else {
 601                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 602                         tbl->is_SGI = 1;
 603
 604                 if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
 605                     (rate_n_flags & RATE_MCS_DUP_MSK))
 606                         tbl->is_ht40 = 1;
 607
 608                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 609                         tbl->is_dup = 1;
 610
 611                 mcs = rs_extract_rate(rate_n_flags);
 612
 613                 /* SISO */
 614                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 615                         if (num_of_ant == 1)
 616                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 617                 /* MIMO2 */
 618                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 619                         if (num_of_ant == 2)
 620                                 tbl->lq_type = LQ_MIMO2;
 621                 /* MIMO3 */
 622                 } else {
 623                         if (num_of_ant == 3) {
 624                                 tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
 625                                 tbl->lq_type = LQ_MIMO3;
 626                         }
 627                 }
 628         }
 629         return 0;
 630 }
 631
 632 /* switch to another antenna/antennas and return 1 */
 633 /* if no other valid antenna found, return 0 */
 634 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 635                              struct iwl_scale_tbl_info *tbl)
 636 {
 637         u8 new_ant_type;
 638
 639         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 640                 return 0;
 641
 642         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 643                 return 0;
 644
 645         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 646
 647         while ((new_ant_type != tbl->ant_type) &&
 648                !rs_is_valid_ant(valid_ant, new_ant_type))
 649                 new_ant_type = ant_toggle_lookup[new_ant_type];
 650
 651         if (new_ant_type == tbl->ant_type)
 652                 return 0;
 653
 654         tbl->ant_type = new_ant_type;
 655         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 656         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 657         return 1;
 658 }
 659
 660 /**
 661  * Green-field mode is valid if the station supports it and
 662  * there are no non-GF stations present in the BSS.
 663  */
 664 static inline u8 rs_use_green(struct ieee80211_sta *sta,
 665                               struct iwl_ht_info *ht_conf)
 666 {
 667         return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
 668                 !(ht_conf->non_GF_STA_present);
 669 }
 670
 671 /**
 672  * rs_get_supported_rates - get the available rates
 673  *
 674  * if management frame or broadcast frame only return
 675  * basic available rates.
 676  *
 677  */
 678 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 679                                   struct ieee80211_hdr *hdr,
 680                                   enum iwl_table_type rate_type)
 681 {
 682         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 683             lq_sta->active_rate_basic)
 684                 return lq_sta->active_rate_basic;
 685
 686         if (is_legacy(rate_type)) {
 687                 return lq_sta->active_legacy_rate;
 688         } else {
 689                 if (is_siso(rate_type))
 690                         return lq_sta->active_siso_rate;
 691                 else if (is_mimo2(rate_type))
 692                         return lq_sta->active_mimo2_rate;
 693                 else
 694                         return lq_sta->active_mimo3_rate;
 695         }
 696 }
 697
 698 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 699                                 int rate_type)
 700 {
 701         u8 high = IWL_RATE_INVALID;
 702         u8 low = IWL_RATE_INVALID;
 703
 704         /* 802.11A or ht walks to the next literal adjacent rate in
 705          * the rate table */
 706         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 707                 int i;
 708                 u32 mask;
 709
 710                 /* Find the previous rate that is in the rate mask */
 711                 i = index - 1;
 712                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 713                         if (rate_mask & mask) {
 714                                 low = i;
 715                                 break;
 716                         }
 717                 }
 718
 719                 /* Find the next rate that is in the rate mask */
 720                 i = index + 1;
 721                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 722                         if (rate_mask & mask) {
 723                                 high = i;
 724                                 break;
 725                         }
 726                 }
 727
 728                 return (high << 8) | low;
 729         }
 730
 731         low = index;
 732         while (low != IWL_RATE_INVALID) {
 733                 low = iwl_rates[low].prev_rs;
 734                 if (low == IWL_RATE_INVALID)
 735                         break;
 736                 if (rate_mask & (1 << low))
 737                         break;
 738                 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
 739         }
 740
 741         high = index;
 742         while (high != IWL_RATE_INVALID) {
 743                 high = iwl_rates[high].next_rs;
 744                 if (high == IWL_RATE_INVALID)
 745                         break;
 746                 if (rate_mask & (1 << high))
 747                         break;
 748                 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
 749         }
 750
 751         return (high << 8) | low;
 752 }
 753
 754 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 755                              struct iwl_scale_tbl_info *tbl,
 756                              u8 scale_index, u8 ht_possible)
 757 {
 758         s32 low;
 759         u16 rate_mask;
 760         u16 high_low;
 761         u8 switch_to_legacy = 0;
 762         u8 is_green = lq_sta->is_green;
 763         struct iwl_priv *priv = lq_sta->drv;
 764
 765         /* check if we need to switch from HT to legacy rates.
 766          * assumption is that mandatory rates (1Mbps or 6Mbps)
 767          * are always supported (spec demand) */
 768         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 769                 switch_to_legacy = 1;
 770                 scale_index = rs_ht_to_legacy[scale_index];
 771                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 772                         tbl->lq_type = LQ_A;
 773                 else
 774                         tbl->lq_type = LQ_G;
 775
 776                 if (num_of_ant(tbl->ant_type) > 1)
 777                         tbl->ant_type =
 778                                 first_antenna(priv->hw_params.valid_tx_ant);
 779
 780                 tbl->is_ht40 = 0;
 781                 tbl->is_SGI = 0;
 782                 tbl->max_search = IWL_MAX_SEARCH;
 783         }
 784
 785         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 786
 787         /* Mask with station rate restriction */
 788         if (is_legacy(tbl->lq_type)) {
 789                 /* supp_rates has no CCK bits in A mode */
 790                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 791                         rate_mask  = (u16)(rate_mask &
 792                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 793                 else
 794                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 795         }
 796
 797         /* If we switched from HT to legacy, check current rate */
 798         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 799                 low = scale_index;
 800                 goto out;
 801         }
 802
 803         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 804                                         tbl->lq_type);
 805         low = high_low & 0xff;
 806
 807         if (low == IWL_RATE_INVALID)
 808                 low = scale_index;
 809
 810 out:
 811         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 812 }
 813
 814 /*
 815  * mac80211 sends us Tx status
 816  */
 817 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 818                          struct ieee80211_sta *sta, void *priv_sta,
 819                          struct sk_buff *skb)
 820 {
 821         int status;
 822         u8 retries;
 823         int rs_index, mac_index, index = 0;
 824         struct iwl_lq_sta *lq_sta = priv_sta;
 825         struct iwl_link_quality_cmd *table;
 826         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 827         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 828         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 829         struct iwl_rate_scale_data *window = NULL;
 830         struct iwl_rate_scale_data *search_win = NULL;
 831         enum mac80211_rate_control_flags mac_flags;
 832         u32 tx_rate;
 833         struct iwl_scale_tbl_info tbl_type;
 834         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
 835         u8 active_index = 0;
 836         s32 tpt = 0;
 837
 838         IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 839
 840         if (!ieee80211_is_data(hdr->frame_control) ||
 841             info->flags & IEEE80211_TX_CTL_NO_ACK)
 842                 return;
 843
 844         /* This packet was aggregated but doesn't carry rate scale info */
 845         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 846             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 847                 return;
 848
 849         if (info->flags & IEEE80211_TX_STAT_AMPDU)
 850                 retries = 0;
 851         else
 852                 retries = info->status.rates[0].count - 1;
 853
 854         if (retries > 15)
 855                 retries = 15;
 856
 857         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 858             !lq_sta->ibss_sta_added)
 859                 goto out;
 860
 861         table = &lq_sta->lq;
 862         active_index = lq_sta->active_tbl;
 863
 864         curr_tbl = &(lq_sta->lq_info[active_index]);
 865         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
 866         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 867         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
 868
 869         /*
 870          * Ignore this Tx frame response if its initial rate doesn't match
 871          * that of latest Link Quality command.  There may be stragglers
 872          * from a previous Link Quality command, but we're no longer interested
 873          * in those; they're either from the "active" mode while we're trying
 874          * to check "search" mode, or a prior "search" mode after we've moved
 875          * to a new "search" mode (which might become the new "active" mode).
 876          */
 877         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 878         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 879         if (priv->band == IEEE80211_BAND_5GHZ)
 880                 rs_index -= IWL_FIRST_OFDM_RATE;
 881         mac_flags = info->status.rates[0].flags;
 882         mac_index = info->status.rates[0].idx;
 883         /* For HT packets, map MCS to PLCP */
 884         if (mac_flags & IEEE80211_TX_RC_MCS) {
 885                 mac_index &= RATE_MCS_CODE_MSK; /* Remove # of streams */
 886                 if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE))
 887                         mac_index++;
 888                 /*
 889                  * mac80211 HT index is always zero-indexed; we need to move
 890                  * HT OFDM rates after CCK rates in 2.4 GHz band
 891                  */
 892                 if (priv->band == IEEE80211_BAND_2GHZ)
 893                         mac_index += IWL_FIRST_OFDM_RATE;
 894         }
 895
 896         if ((mac_index < 0) ||
 897             (tbl_type.is_SGI != !!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) ||
 898             (tbl_type.is_ht40 != !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 899             (tbl_type.is_dup != !!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) ||
 900             (tbl_type.ant_type != info->antenna_sel_tx) ||
 901             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(mac_flags & IEEE80211_TX_RC_MCS)) ||
 902             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 903             (rs_index != mac_index)) {
 904                 IWL_DEBUG_RATE(priv, "initial rate %d does not match %d (0x%x)\n", mac_index, rs_index, tx_rate);
 905                 /* the last LQ command could failed so the LQ in ucode not
 906                  * the same in driver sync up
 907                  */
 908                 lq_sta->missed_rate_counter++;
 909                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 910                         lq_sta->missed_rate_counter = 0;
 911                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 912                 }
 913                 goto out;
 914         }
 915
 916         lq_sta->missed_rate_counter = 0;
 917         /* Update frame history window with "failure" for each Tx retry. */
 918         while (retries) {
 919                 /* Look up the rate and other info used for each tx attempt.
 920                  * Each tx attempt steps one entry deeper in the rate table. */
 921                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 922                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 923                                           &tbl_type, &rs_index);
 924
 925                 /* If type matches "search" table,
 926                  * add failure to "search" history */
 927                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
 928                     (tbl_type.ant_type == search_tbl->ant_type) &&
 929                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
 930                         if (search_tbl->expected_tpt)
 931                                 tpt = search_tbl->expected_tpt[rs_index];
 932                         else
 933                                 tpt = 0;
 934                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
 935
 936                 /* Else if type matches "current/active" table,
 937                  * add failure to "current/active" history */
 938                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 939                            (tbl_type.ant_type == curr_tbl->ant_type) &&
 940                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 941                         if (curr_tbl->expected_tpt)
 942                                 tpt = curr_tbl->expected_tpt[rs_index];
 943                         else
 944                                 tpt = 0;
 945                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
 946                 }
 947
 948                 /* If not searching for a new mode, increment failed counter
 949                  * ... this helps determine when to start searching again */
 950                 if (lq_sta->stay_in_tbl)
 951                         lq_sta->total_failed++;
 952                 --retries;
 953                 index++;
 954
 955         }
 956
 957         /*
 958          * Find (by rate) the history window to update with final Tx attempt;
 959          * if Tx was successful first try, use original rate,
 960          * else look up the rate that was, finally, successful.
 961          */
 962         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 963         lq_sta->last_rate_n_flags = tx_rate;
 964         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 965
 966         /* Update frame history window with "success" if Tx got ACKed ... */
 967         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
 968
 969         /* If type matches "search" table,
 970          * add final tx status to "search" history */
 971         if ((tbl_type.lq_type == search_tbl->lq_type) &&
 972             (tbl_type.ant_type == search_tbl->ant_type) &&
 973             (tbl_type.is_SGI == search_tbl->is_SGI)) {
 974                 if (search_tbl->expected_tpt)
 975                         tpt = search_tbl->expected_tpt[rs_index];
 976                 else
 977                         tpt = 0;
 978                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 979                         rs_collect_tx_data(search_win, rs_index, tpt,
 980                                            info->status.ampdu_ack_len,
 981                                            info->status.ampdu_ack_map);
 982                 else
 983                         rs_collect_tx_data(search_win, rs_index, tpt,
 984                                            1, status);
 985         /* Else if type matches "current/active" table,
 986          * add final tx status to "current/active" history */
 987         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 988                    (tbl_type.ant_type == curr_tbl->ant_type) &&
 989                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 990                 if (curr_tbl->expected_tpt)
 991                         tpt = curr_tbl->expected_tpt[rs_index];
 992                 else
 993                         tpt = 0;
 994                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 995                         rs_collect_tx_data(window, rs_index, tpt,
 996                                            info->status.ampdu_ack_len,
 997                                            info->status.ampdu_ack_map);
 998                 else
 999                         rs_collect_tx_data(window, rs_index, tpt,
1000                                            1, status);
1001         }
1002
1003         /* If not searching for new mode, increment success/failed counter
1004          * ... these help determine when to start searching again */
1005         if (lq_sta->stay_in_tbl) {
1006                 if (info->flags & IEEE80211_TX_STAT_AMPDU) {
1007                         lq_sta->total_success += info->status.ampdu_ack_map;
1008                         lq_sta->total_failed +=
1009                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
1010                 } else {
1011                         if (status)
1012                                 lq_sta->total_success++;
1013                         else
1014                                 lq_sta->total_failed++;
1015                 }
1016         }
1017
1018         /* See if there's a better rate or modulation mode to try. */
1019         if (sta && sta->supp_rates[sband->band])
1020                 rs_rate_scale_perform(priv, skb, sta, lq_sta);
1021 out:
1022         return;
1023 }
1024
1025 /*
1026  * Begin a period of staying with a selected modulation mode.
1027  * Set "stay_in_tbl" flag to prevent any mode switches.
1028  * Set frame tx success limits according to legacy vs. high-throughput,
1029  * and reset overall (spanning all rates) tx success history statistics.
1030  * These control how long we stay using same modulation mode before
1031  * searching for a new mode.
1032  */
1033 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
1034                                  struct iwl_lq_sta *lq_sta)
1035 {
1036         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
1037         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
1038         if (is_legacy) {
1039                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
1040                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
1041                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
1042         } else {
1043                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
1044                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
1045                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
1046         }
1047         lq_sta->table_count = 0;
1048         lq_sta->total_failed = 0;
1049         lq_sta->total_success = 0;
1050         lq_sta->flush_timer = jiffies;
1051         lq_sta->action_counter = 0;
1052 }
1053
1054 /*
1055  * Find correct throughput table for given mode of modulation
1056  */
1057 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
1058                                       struct iwl_scale_tbl_info *tbl)
1059 {
1060         if (is_legacy(tbl->lq_type)) {
1061                 if (!is_a_band(tbl->lq_type))
1062                         tbl->expected_tpt = expected_tpt_G;
1063                 else
1064                         tbl->expected_tpt = expected_tpt_A;
1065         } else if (is_siso(tbl->lq_type)) {
1066                 if (tbl->is_ht40 && !lq_sta->is_dup)
1067                         if (tbl->is_SGI)
1068                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
1069                         else
1070                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1071                 else if (tbl->is_SGI)
1072                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1073                 else
1074                         tbl->expected_tpt = expected_tpt_siso20MHz;
1075         } else if (is_mimo2(tbl->lq_type)) {
1076                 if (tbl->is_ht40 && !lq_sta->is_dup)
1077                         if (tbl->is_SGI)
1078                                 tbl->expected_tpt = expected_tpt_mimo2_40MHzSGI;
1079                         else
1080                                 tbl->expected_tpt = expected_tpt_mimo2_40MHz;
1081                 else if (tbl->is_SGI)
1082                         tbl->expected_tpt = expected_tpt_mimo2_20MHzSGI;
1083                 else
1084                         tbl->expected_tpt = expected_tpt_mimo2_20MHz;
1085         } else if (is_mimo3(tbl->lq_type)) {
1086                 if (tbl->is_ht40 && !lq_sta->is_dup)
1087                         if (tbl->is_SGI)
1088                                 tbl->expected_tpt = expected_tpt_mimo3_40MHzSGI;
1089                         else
1090                                 tbl->expected_tpt = expected_tpt_mimo3_40MHz;
1091                 else if (tbl->is_SGI)
1092                         tbl->expected_tpt = expected_tpt_mimo3_20MHzSGI;
1093                 else
1094                         tbl->expected_tpt = expected_tpt_mimo3_20MHz;
1095         } else
1096                 tbl->expected_tpt = expected_tpt_G;
1097 }
1098
1099 /*
1100  * Find starting rate for new "search" high-throughput mode of modulation.
1101  * Goal is to find lowest expected rate (under perfect conditions) that is
1102  * above the current measured throughput of "active" mode, to give new mode
1103  * a fair chance to prove itself without too many challenges.
1104  *
1105  * This gets called when transitioning to more aggressive modulation
1106  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1107  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1108  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1109  * bit rate will typically need to increase, but not if performance was bad.
1110  */
1111 static s32 rs_get_best_rate(struct iwl_priv *priv,
1112                             struct iwl_lq_sta *lq_sta,
1113                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1114                             u16 rate_mask, s8 index)
1115 {
1116         /* "active" values */
1117         struct iwl_scale_tbl_info *active_tbl =
1118             &(lq_sta->lq_info[lq_sta->active_tbl]);
1119         s32 active_sr = active_tbl->win[index].success_ratio;
1120         s32 active_tpt = active_tbl->expected_tpt[index];
1121
1122         /* expected "search" throughput */
1123         s32 *tpt_tbl = tbl->expected_tpt;
1124
1125         s32 new_rate, high, low, start_hi;
1126         u16 high_low;
1127         s8 rate = index;
1128
1129         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1130
1131         for (; ;) {
1132                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1133                                                 tbl->lq_type);
1134
1135                 low = high_low & 0xff;
1136                 high = (high_low >> 8) & 0xff;
1137
1138                 /*
1139                  * Lower the "search" bit rate, to give new "search" mode
1140                  * approximately the same throughput as "active" if:
1141                  *
1142                  * 1) "Active" mode has been working modestly well (but not
1143                  *    great), and expected "search" throughput (under perfect
1144                  *    conditions) at candidate rate is above the actual
1145                  *    measured "active" throughput (but less than expected
1146                  *    "active" throughput under perfect conditions).
1147                  * OR
1148                  * 2) "Active" mode has been working perfectly or very well
1149                  *    and expected "search" throughput (under perfect
1150                  *    conditions) at candidate rate is above expected
1151                  *    "active" throughput (under perfect conditions).
1152                  */
1153                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1154                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1155                       (active_sr <= IWL_RATE_HIGH_TH) &&
1156                       (tpt_tbl[rate] <= active_tpt))) ||
1157                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1158                      (tpt_tbl[rate] > active_tpt))) {
1159
1160                         /* (2nd or later pass)
1161                          * If we've already tried to raise the rate, and are
1162                          * now trying to lower it, use the higher rate. */
1163                         if (start_hi != IWL_RATE_INVALID) {
1164                                 new_rate = start_hi;
1165                                 break;
1166                         }
1167
1168                         new_rate = rate;
1169
1170                         /* Loop again with lower rate */
1171                         if (low != IWL_RATE_INVALID)
1172                                 rate = low;
1173
1174                         /* Lower rate not available, use the original */
1175                         else
1176                                 break;
1177
1178                 /* Else try to raise the "search" rate to match "active" */
1179                 } else {
1180                         /* (2nd or later pass)
1181                          * If we've already tried to lower the rate, and are
1182                          * now trying to raise it, use the lower rate. */
1183                         if (new_rate != IWL_RATE_INVALID)
1184                                 break;
1185
1186                         /* Loop again with higher rate */
1187                         else if (high != IWL_RATE_INVALID) {
1188                                 start_hi = high;
1189                                 rate = high;
1190
1191                         /* Higher rate not available, use the original */
1192                         } else {
1193                                 new_rate = rate;
1194                                 break;
1195                         }
1196                 }
1197         }
1198
1199         return new_rate;
1200 }
1201
1202 /*
1203  * Set up search table for MIMO2
1204  */
1205 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1206                              struct iwl_lq_sta *lq_sta,
1207                              struct ieee80211_conf *conf,
1208                              struct ieee80211_sta *sta,
1209                              struct iwl_scale_tbl_info *tbl, int index)
1210 {
1211         u16 rate_mask;
1212         s32 rate;
1213         s8 is_green = lq_sta->is_green;
1214
1215         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1216                 return -1;
1217
1218         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1219                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1220                 return -1;
1221
1222         /* Need both Tx chains/antennas to support MIMO */
1223         if (priv->hw_params.tx_chains_num < 2)
1224                 return -1;
1225
1226         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1227
1228         tbl->lq_type = LQ_MIMO2;
1229         tbl->is_dup = lq_sta->is_dup;
1230         tbl->action = 0;
1231         tbl->max_search = IWL_MAX_SEARCH;
1232         rate_mask = lq_sta->active_mimo2_rate;
1233
1234         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1235                 tbl->is_ht40 = 1;
1236         else
1237                 tbl->is_ht40 = 0;
1238
1239         rs_set_expected_tpt_table(lq_sta, tbl);
1240
1241         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1242
1243         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1244         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1245                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1246                                                 rate, rate_mask);
1247                 return -1;
1248         }
1249         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1250
1251         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1252                      tbl->current_rate, is_green);
1253         return 0;
1254 }
1255
1256 /*
1257  * Set up search table for MIMO3
1258  */
1259 static int rs_switch_to_mimo3(struct iwl_priv *priv,
1260                              struct iwl_lq_sta *lq_sta,
1261                              struct ieee80211_conf *conf,
1262                              struct ieee80211_sta *sta,
1263                              struct iwl_scale_tbl_info *tbl, int index)
1264 {
1265         u16 rate_mask;
1266         s32 rate;
1267         s8 is_green = lq_sta->is_green;
1268
1269         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1270                 return -1;
1271
1272         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1273                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1274                 return -1;
1275
1276         /* Need both Tx chains/antennas to support MIMO */
1277         if (priv->hw_params.tx_chains_num < 3)
1278                 return -1;
1279
1280         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO3\n");
1281
1282         tbl->lq_type = LQ_MIMO3;
1283         tbl->is_dup = lq_sta->is_dup;
1284         tbl->action = 0;
1285         tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
1286         rate_mask = lq_sta->active_mimo3_rate;
1287
1288         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1289                 tbl->is_ht40 = 1;
1290         else
1291                 tbl->is_ht40 = 0;
1292
1293         rs_set_expected_tpt_table(lq_sta, tbl);
1294
1295         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1296
1297         IWL_DEBUG_RATE(priv, "LQ: MIMO3 best rate %d mask %X\n",
1298                 rate, rate_mask);
1299         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1300                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1301                                                 rate, rate_mask);
1302                 return -1;
1303         }
1304         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1305
1306         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1307                      tbl->current_rate, is_green);
1308         return 0;
1309 }
1310
1311 /*
1312  * Set up search table for SISO
1313  */
1314 static int rs_switch_to_siso(struct iwl_priv *priv,
1315                              struct iwl_lq_sta *lq_sta,
1316                              struct ieee80211_conf *conf,
1317                              struct ieee80211_sta *sta,
1318                              struct iwl_scale_tbl_info *tbl, int index)
1319 {
1320         u16 rate_mask;
1321         u8 is_green = lq_sta->is_green;
1322         s32 rate;
1323
1324         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1325                 return -1;
1326
1327         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1328
1329         tbl->is_dup = lq_sta->is_dup;
1330         tbl->lq_type = LQ_SISO;
1331         tbl->action = 0;
1332         tbl->max_search = IWL_MAX_SEARCH;
1333         rate_mask = lq_sta->active_siso_rate;
1334
1335         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1336                 tbl->is_ht40 = 1;
1337         else
1338                 tbl->is_ht40 = 0;
1339
1340         if (is_green)
1341                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1342
1343         rs_set_expected_tpt_table(lq_sta, tbl);
1344         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1345
1346         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1347         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1348                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1349                              rate, rate_mask);
1350                 return -1;
1351         }
1352         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1353         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1354                      tbl->current_rate, is_green);
1355         return 0;
1356 }
1357
1358 /*
1359  * Try to switch to new modulation mode from legacy
1360  */
1361 static int rs_move_legacy_other(struct iwl_priv *priv,
1362                                 struct iwl_lq_sta *lq_sta,
1363                                 struct ieee80211_conf *conf,
1364                                 struct ieee80211_sta *sta,
1365                                 int index)
1366 {
1367         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1368         struct iwl_scale_tbl_info *search_tbl =
1369                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1370         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1371         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1372                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1373         u8 start_action = tbl->action;
1374         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1375         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1376         int ret = 0;
1377         u8 update_search_tbl_counter = 0;
1378
1379         if (!iwl_ht_enabled(priv))
1380                 /* stay in Legacy */
1381                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1382         else if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1383                    tbl->action > IWL_LEGACY_SWITCH_SISO)
1384                 tbl->action = IWL_LEGACY_SWITCH_SISO;
1385         for (; ;) {
1386                 lq_sta->action_counter++;
1387                 switch (tbl->action) {
1388                 case IWL_LEGACY_SWITCH_ANTENNA1:
1389                 case IWL_LEGACY_SWITCH_ANTENNA2:
1390                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1391
1392                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1393                                                         tx_chains_num <= 1) ||
1394                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1395                                                         tx_chains_num <= 2))
1396                                 break;
1397
1398                         /* Don't change antenna if success has been great */
1399                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1400                                 break;
1401
1402                         /* Set up search table to try other antenna */
1403                         memcpy(search_tbl, tbl, sz);
1404
1405                         if (rs_toggle_antenna(valid_tx_ant,
1406                                 &search_tbl->current_rate, search_tbl)) {
1407                                 update_search_tbl_counter = 1;
1408                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1409                                 goto out;
1410                         }
1411                         break;
1412                 case IWL_LEGACY_SWITCH_SISO:
1413                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1414
1415                         /* Set up search table to try SISO */
1416                         memcpy(search_tbl, tbl, sz);
1417                         search_tbl->is_SGI = 0;
1418                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1419                                                  search_tbl, index);
1420                         if (!ret) {
1421                                 lq_sta->action_counter = 0;
1422                                 goto out;
1423                         }
1424
1425                         break;
1426                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1427                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1428                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1429                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1430
1431                         /* Set up search table to try MIMO */
1432                         memcpy(search_tbl, tbl, sz);
1433                         search_tbl->is_SGI = 0;
1434
1435                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1436                                 search_tbl->ant_type = ANT_AB;
1437                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1438                                 search_tbl->ant_type = ANT_AC;
1439                         else
1440                                 search_tbl->ant_type = ANT_BC;
1441
1442                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1443                                 break;
1444
1445                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1446                                                  search_tbl, index);
1447                         if (!ret) {
1448                                 lq_sta->action_counter = 0;
1449                                 goto out;
1450                         }
1451                         break;
1452
1453                 case IWL_LEGACY_SWITCH_MIMO3_ABC:
1454                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO3\n");
1455
1456                         /* Set up search table to try MIMO3 */
1457                         memcpy(search_tbl, tbl, sz);
1458                         search_tbl->is_SGI = 0;
1459
1460                         search_tbl->ant_type = ANT_ABC;
1461
1462                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1463                                 break;
1464
1465                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1466                                                  search_tbl, index);
1467                         if (!ret) {
1468                                 lq_sta->action_counter = 0;
1469                                 goto out;
1470                         }
1471                         break;
1472                 }
1473                 tbl->action++;
1474                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1475                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1476
1477                 if (tbl->action == start_action)
1478                         break;
1479
1480         }
1481         search_tbl->lq_type = LQ_NONE;
1482         return 0;
1483
1484 out:
1485         lq_sta->search_better_tbl = 1;
1486         tbl->action++;
1487         if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1488                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1489         if (update_search_tbl_counter)
1490                 search_tbl->action = tbl->action;
1491         return 0;
1492
1493 }
1494
1495 /*
1496  * Try to switch to new modulation mode from SISO
1497  */
1498 static int rs_move_siso_to_other(struct iwl_priv *priv,
1499                                  struct iwl_lq_sta *lq_sta,
1500                                  struct ieee80211_conf *conf,
1501                                  struct ieee80211_sta *sta, int index)
1502 {
1503         u8 is_green = lq_sta->is_green;
1504         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1505         struct iwl_scale_tbl_info *search_tbl =
1506                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1507         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1508         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1509         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1510                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1511         u8 start_action = tbl->action;
1512         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1513         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1514         u8 update_search_tbl_counter = 0;
1515         int ret;
1516
1517         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1518             tbl->action > IWL_SISO_SWITCH_ANTENNA2) {
1519                 /* stay in SISO */
1520                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1521         }
1522         for (;;) {
1523                 lq_sta->action_counter++;
1524                 switch (tbl->action) {
1525                 case IWL_SISO_SWITCH_ANTENNA1:
1526                 case IWL_SISO_SWITCH_ANTENNA2:
1527                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1528
1529                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1530                                                         tx_chains_num <= 1) ||
1531                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1532                                                         tx_chains_num <= 2))
1533                                 break;
1534
1535                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1536                                 break;
1537
1538                         memcpy(search_tbl, tbl, sz);
1539                         if (rs_toggle_antenna(valid_tx_ant,
1540                                        &search_tbl->current_rate, search_tbl)) {
1541                                 update_search_tbl_counter = 1;
1542                                 goto out;
1543                         }
1544                         break;
1545                 case IWL_SISO_SWITCH_MIMO2_AB:
1546                 case IWL_SISO_SWITCH_MIMO2_AC:
1547                 case IWL_SISO_SWITCH_MIMO2_BC:
1548                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1549                         memcpy(search_tbl, tbl, sz);
1550                         search_tbl->is_SGI = 0;
1551
1552                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1553                                 search_tbl->ant_type = ANT_AB;
1554                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1555                                 search_tbl->ant_type = ANT_AC;
1556                         else
1557                                 search_tbl->ant_type = ANT_BC;
1558
1559                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1560                                 break;
1561
1562                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1563                                                  search_tbl, index);
1564                         if (!ret)
1565                                 goto out;
1566                         break;
1567                 case IWL_SISO_SWITCH_GI:
1568                         if (!tbl->is_ht40 && !(ht_cap->cap &
1569                                                 IEEE80211_HT_CAP_SGI_20))
1570                                 break;
1571                         if (tbl->is_ht40 && !(ht_cap->cap &
1572                                                 IEEE80211_HT_CAP_SGI_40))
1573                                 break;
1574
1575                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1576
1577                         memcpy(search_tbl, tbl, sz);
1578                         if (is_green) {
1579                                 if (!tbl->is_SGI)
1580                                         break;
1581                                 else
1582                                         IWL_ERR(priv,
1583                                                 "SGI was set in GF+SISO\n");
1584                         }
1585                         search_tbl->is_SGI = !tbl->is_SGI;
1586                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1587                         if (tbl->is_SGI) {
1588                                 s32 tpt = lq_sta->last_tpt / 100;
1589                                 if (tpt >= search_tbl->expected_tpt[index])
1590                                         break;
1591                         }
1592                         search_tbl->current_rate =
1593                                 rate_n_flags_from_tbl(priv, search_tbl,
1594                                                       index, is_green);
1595                         update_search_tbl_counter = 1;
1596                         goto out;
1597                 case IWL_SISO_SWITCH_MIMO3_ABC:
1598                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO3\n");
1599                         memcpy(search_tbl, tbl, sz);
1600                         search_tbl->is_SGI = 0;
1601                         search_tbl->ant_type = ANT_ABC;
1602
1603                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1604                                 break;
1605
1606                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1607                                                  search_tbl, index);
1608                         if (!ret)
1609                                 goto out;
1610                         break;
1611                 }
1612                 tbl->action++;
1613                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1614                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1615
1616                 if (tbl->action == start_action)
1617                         break;
1618         }
1619         search_tbl->lq_type = LQ_NONE;
1620         return 0;
1621
1622  out:
1623         lq_sta->search_better_tbl = 1;
1624         tbl->action++;
1625         if (tbl->action > IWL_SISO_SWITCH_MIMO3_ABC)
1626                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1627         if (update_search_tbl_counter)
1628                 search_tbl->action = tbl->action;
1629
1630         return 0;
1631 }
1632
1633 /*
1634  * Try to switch to new modulation mode from MIMO2
1635  */
1636 static int rs_move_mimo2_to_other(struct iwl_priv *priv,
1637                                  struct iwl_lq_sta *lq_sta,
1638                                  struct ieee80211_conf *conf,
1639                                  struct ieee80211_sta *sta, int index)
1640 {
1641         s8 is_green = lq_sta->is_green;
1642         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1643         struct iwl_scale_tbl_info *search_tbl =
1644                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1645         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1646         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1647         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1648                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1649         u8 start_action = tbl->action;
1650         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1651         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1652         u8 update_search_tbl_counter = 0;
1653         int ret;
1654
1655         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1656             (tbl->action < IWL_MIMO2_SWITCH_SISO_A ||
1657              tbl->action > IWL_MIMO2_SWITCH_SISO_C)) {
1658                 /* switch in SISO */
1659                 tbl->action = IWL_MIMO2_SWITCH_SISO_A;
1660         }
1661         for (;;) {
1662                 lq_sta->action_counter++;
1663                 switch (tbl->action) {
1664                 case IWL_MIMO2_SWITCH_ANTENNA1:
1665                 case IWL_MIMO2_SWITCH_ANTENNA2:
1666                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1667
1668                         if (tx_chains_num <= 2)
1669                                 break;
1670
1671                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1672                                 break;
1673
1674                         memcpy(search_tbl, tbl, sz);
1675                         if (rs_toggle_antenna(valid_tx_ant,
1676                                        &search_tbl->current_rate, search_tbl)) {
1677                                 update_search_tbl_counter = 1;
1678                                 goto out;
1679                         }
1680                         break;
1681                 case IWL_MIMO2_SWITCH_SISO_A:
1682                 case IWL_MIMO2_SWITCH_SISO_B:
1683                 case IWL_MIMO2_SWITCH_SISO_C:
1684                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1685
1686                         /* Set up new search table for SISO */
1687                         memcpy(search_tbl, tbl, sz);
1688
1689                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1690                                 search_tbl->ant_type = ANT_A;
1691                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1692                                 search_tbl->ant_type = ANT_B;
1693                         else
1694                                 search_tbl->ant_type = ANT_C;
1695
1696                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1697                                 break;
1698
1699                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1700                                                  search_tbl, index);
1701                         if (!ret)
1702                                 goto out;
1703
1704                         break;
1705
1706                 case IWL_MIMO2_SWITCH_GI:
1707                         if (!tbl->is_ht40 && !(ht_cap->cap &
1708                                                 IEEE80211_HT_CAP_SGI_20))
1709                                 break;
1710                         if (tbl->is_ht40 && !(ht_cap->cap &
1711                                                 IEEE80211_HT_CAP_SGI_40))
1712                                 break;
1713
1714                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1715
1716                         /* Set up new search table for MIMO2 */
1717                         memcpy(search_tbl, tbl, sz);
1718                         search_tbl->is_SGI = !tbl->is_SGI;
1719                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1720                         /*
1721                          * If active table already uses the fastest possible
1722                          * modulation (dual stream with short guard interval),
1723                          * and it's working well, there's no need to look
1724                          * for a better type of modulation!
1725                          */
1726                         if (tbl->is_SGI) {
1727                                 s32 tpt = lq_sta->last_tpt / 100;
1728                                 if (tpt >= search_tbl->expected_tpt[index])
1729                                         break;
1730                         }
1731                         search_tbl->current_rate =
1732                                 rate_n_flags_from_tbl(priv, search_tbl,
1733                                                       index, is_green);
1734                         update_search_tbl_counter = 1;
1735                         goto out;
1736
1737                 case IWL_MIMO2_SWITCH_MIMO3_ABC:
1738                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to MIMO3\n");
1739                         memcpy(search_tbl, tbl, sz);
1740                         search_tbl->is_SGI = 0;
1741                         search_tbl->ant_type = ANT_ABC;
1742
1743                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1744                                 break;
1745
1746                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1747                                                  search_tbl, index);
1748                         if (!ret)
1749                                 goto out;
1750
1751                         break;
1752                 }
1753                 tbl->action++;
1754                 if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1755                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1756
1757                 if (tbl->action == start_action)
1758                         break;
1759         }
1760         search_tbl->lq_type = LQ_NONE;
1761         return 0;
1762  out:
1763         lq_sta->search_better_tbl = 1;
1764         tbl->action++;
1765         if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1766                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1767         if (update_search_tbl_counter)
1768                 search_tbl->action = tbl->action;
1769
1770         return 0;
1771
1772 }
1773
1774 /*
1775  * Try to switch to new modulation mode from MIMO3
1776  */
1777 static int rs_move_mimo3_to_other(struct iwl_priv *priv,
1778                                  struct iwl_lq_sta *lq_sta,
1779                                  struct ieee80211_conf *conf,
1780                                  struct ieee80211_sta *sta, int index)
1781 {
1782         s8 is_green = lq_sta->is_green;
1783         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1784         struct iwl_scale_tbl_info *search_tbl =
1785                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1786         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1787         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1788         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1789                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1790         u8 start_action = tbl->action;
1791         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1792         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1793         int ret;
1794         u8 update_search_tbl_counter = 0;
1795
1796         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1797             (tbl->action < IWL_MIMO3_SWITCH_SISO_A ||
1798              tbl->action > IWL_MIMO3_SWITCH_SISO_C)) {
1799                 /* switch in SISO */
1800                 tbl->action = IWL_MIMO3_SWITCH_SISO_A;
1801         }
1802         for (;;) {
1803                 lq_sta->action_counter++;
1804                 switch (tbl->action) {
1805                 case IWL_MIMO3_SWITCH_ANTENNA1:
1806                 case IWL_MIMO3_SWITCH_ANTENNA2:
1807                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle Antennas\n");
1808
1809                         if (tx_chains_num <= 3)
1810                                 break;
1811
1812                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1813                                 break;
1814
1815                         memcpy(search_tbl, tbl, sz);
1816                         if (rs_toggle_antenna(valid_tx_ant,
1817                                        &search_tbl->current_rate, search_tbl))
1818                                 goto out;
1819                         break;
1820                 case IWL_MIMO3_SWITCH_SISO_A:
1821                 case IWL_MIMO3_SWITCH_SISO_B:
1822                 case IWL_MIMO3_SWITCH_SISO_C:
1823                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to SISO\n");
1824
1825                         /* Set up new search table for SISO */
1826                         memcpy(search_tbl, tbl, sz);
1827
1828                         if (tbl->action == IWL_MIMO3_SWITCH_SISO_A)
1829                                 search_tbl->ant_type = ANT_A;
1830                         else if (tbl->action == IWL_MIMO3_SWITCH_SISO_B)
1831                                 search_tbl->ant_type = ANT_B;
1832                         else
1833                                 search_tbl->ant_type = ANT_C;
1834
1835                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1836                                 break;
1837
1838                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1839                                                  search_tbl, index);
1840                         if (!ret)
1841                                 goto out;
1842
1843                         break;
1844
1845                 case IWL_MIMO3_SWITCH_MIMO2_AB:
1846                 case IWL_MIMO3_SWITCH_MIMO2_AC:
1847                 case IWL_MIMO3_SWITCH_MIMO2_BC:
1848                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to MIMO2\n");
1849
1850                         memcpy(search_tbl, tbl, sz);
1851                         search_tbl->is_SGI = 0;
1852                         if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AB)
1853                                 search_tbl->ant_type = ANT_AB;
1854                         else if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AC)
1855                                 search_tbl->ant_type = ANT_AC;
1856                         else
1857                                 search_tbl->ant_type = ANT_BC;
1858
1859                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1860                                 break;
1861
1862                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1863                                                  search_tbl, index);
1864                         if (!ret)
1865                                 goto out;
1866
1867                         break;
1868
1869                 case IWL_MIMO3_SWITCH_GI:
1870                         if (!tbl->is_ht40 && !(ht_cap->cap &
1871                                                 IEEE80211_HT_CAP_SGI_20))
1872                                 break;
1873                         if (tbl->is_ht40 && !(ht_cap->cap &
1874                                                 IEEE80211_HT_CAP_SGI_40))
1875                                 break;
1876
1877                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle SGI/NGI\n");
1878
1879                         /* Set up new search table for MIMO */
1880                         memcpy(search_tbl, tbl, sz);
1881                         search_tbl->is_SGI = !tbl->is_SGI;
1882                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1883                         /*
1884                          * If active table already uses the fastest possible
1885                          * modulation (dual stream with short guard interval),
1886                          * and it's working well, there's no need to look
1887                          * for a better type of modulation!
1888                          */
1889                         if (tbl->is_SGI) {
1890                                 s32 tpt = lq_sta->last_tpt / 100;
1891                                 if (tpt >= search_tbl->expected_tpt[index])
1892                                         break;
1893                         }
1894                         search_tbl->current_rate =
1895                                 rate_n_flags_from_tbl(priv, search_tbl,
1896                                                       index, is_green);
1897                         update_search_tbl_counter = 1;
1898                         goto out;
1899                 }
1900                 tbl->action++;
1901                 if (tbl->action > IWL_MIMO3_SWITCH_GI)
1902                         tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1903
1904                 if (tbl->action == start_action)
1905                         break;
1906         }
1907         search_tbl->lq_type = LQ_NONE;
1908         return 0;
1909  out:
1910         lq_sta->search_better_tbl = 1;
1911         tbl->action++;
1912         if (tbl->action > IWL_MIMO3_SWITCH_GI)
1913                 tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1914         if (update_search_tbl_counter)
1915                 search_tbl->action = tbl->action;
1916
1917         return 0;
1918
1919 }
1920
1921 /*
1922  * Check whether we should continue using same modulation mode, or
1923  * begin search for a new mode, based on:
1924  * 1) # tx successes or failures while using this mode
1925  * 2) # times calling this function
1926  * 3) elapsed time in this mode (not used, for now)
1927  */
1928 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1929 {
1930         struct iwl_scale_tbl_info *tbl;
1931         int i;
1932         int active_tbl;
1933         int flush_interval_passed = 0;
1934         struct iwl_priv *priv;
1935
1936         priv = lq_sta->drv;
1937         active_tbl = lq_sta->active_tbl;
1938
1939         tbl = &(lq_sta->lq_info[active_tbl]);
1940
1941         /* If we've been disallowing search, see if we should now allow it */
1942         if (lq_sta->stay_in_tbl) {
1943
1944                 /* Elapsed time using current modulation mode */
1945                 if (lq_sta->flush_timer)
1946                         flush_interval_passed =
1947                         time_after(jiffies,
1948                                         (unsigned long)(lq_sta->flush_timer +
1949                                         IWL_RATE_SCALE_FLUSH_INTVL));
1950
1951                 /*
1952                  * Check if we should allow search for new modulation mode.
1953                  * If many frames have failed or succeeded, or we've used
1954                  * this same modulation for a long time, allow search, and
1955                  * reset history stats that keep track of whether we should
1956                  * allow a new search.  Also (below) reset all bitmaps and
1957                  * stats in active history.
1958                  */
1959                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1960                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1961                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1962                      && (flush_interval_passed))) {
1963                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1964                                      lq_sta->total_failed,
1965                                      lq_sta->total_success,
1966                                      flush_interval_passed);
1967
1968                         /* Allow search for new mode */
1969                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1970                         lq_sta->total_failed = 0;
1971                         lq_sta->total_success = 0;
1972                         lq_sta->flush_timer = 0;
1973
1974                 /*
1975                  * Else if we've used this modulation mode enough repetitions
1976                  * (regardless of elapsed time or success/failure), reset
1977                  * history bitmaps and rate-specific stats for all rates in
1978                  * active table.
1979                  */
1980                 } else {
1981                         lq_sta->table_count++;
1982                         if (lq_sta->table_count >=
1983                             lq_sta->table_count_limit) {
1984                                 lq_sta->table_count = 0;
1985
1986                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
1987                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1988                                         rs_rate_scale_clear_window(
1989                                                 &(tbl->win[i]));
1990                         }
1991                 }
1992
1993                 /* If transitioning to allow "search", reset all history
1994                  * bitmaps and stats in active table (this will become the new
1995                  * "search" table). */
1996                 if (!lq_sta->stay_in_tbl) {
1997                         for (i = 0; i < IWL_RATE_COUNT; i++)
1998                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1999                 }
2000         }
2001 }
2002
2003 /*
2004  * setup rate table in uCode
2005  * return rate_n_flags as used in the table
2006  */
2007 static u32 rs_update_rate_tbl(struct iwl_priv *priv,
2008                                 struct iwl_lq_sta *lq_sta,
2009                                 struct iwl_scale_tbl_info *tbl,
2010                                 int index, u8 is_green)
2011 {
2012         u32 rate;
2013
2014         /* Update uCode's rate table. */
2015         rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2016         rs_fill_link_cmd(priv, lq_sta, rate);
2017         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2018
2019         return rate;
2020 }
2021
2022 /*
2023  * Do rate scaling and search for new modulation mode.
2024  */
2025 static void rs_rate_scale_perform(struct iwl_priv *priv,
2026                                   struct sk_buff *skb,
2027                                   struct ieee80211_sta *sta,
2028                                   struct iwl_lq_sta *lq_sta)
2029 {
2030         struct ieee80211_hw *hw = priv->hw;
2031         struct ieee80211_conf *conf = &hw->conf;
2032         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2033         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2034         int low = IWL_RATE_INVALID;
2035         int high = IWL_RATE_INVALID;
2036         int index;
2037         int i;
2038         struct iwl_rate_scale_data *window = NULL;
2039         int current_tpt = IWL_INVALID_VALUE;
2040         int low_tpt = IWL_INVALID_VALUE;
2041         int high_tpt = IWL_INVALID_VALUE;
2042         u32 fail_count;
2043         s8 scale_action = 0;
2044         u16 rate_mask;
2045         u8 update_lq = 0;
2046         struct iwl_scale_tbl_info *tbl, *tbl1;
2047         u16 rate_scale_index_msk = 0;
2048         u32 rate;
2049         u8 is_green = 0;
2050         u8 active_tbl = 0;
2051         u8 done_search = 0;
2052         u16 high_low;
2053         s32 sr;
2054         u8 tid = MAX_TID_COUNT;
2055         struct iwl_tid_data *tid_data;
2056
2057         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
2058
2059         /* Send management frames and NO_ACK data using lowest rate. */
2060         /* TODO: this could probably be improved.. */
2061         if (!ieee80211_is_data(hdr->frame_control) ||
2062             info->flags & IEEE80211_TX_CTL_NO_ACK)
2063                 return;
2064
2065         if (!sta || !lq_sta)
2066                 return;
2067
2068         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
2069
2070         tid = rs_tl_add_packet(lq_sta, hdr);
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
2172         /* Else we have enough samples; calculate estimate of
2173          * actual average throughput */
2174
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
2685         rs_initialize_lq(priv, conf, sta, lq_sta);
2686 }
2687
2688 static void rs_fill_link_cmd(struct iwl_priv *priv,
2689                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2690 {
2691         struct iwl_scale_tbl_info tbl_type;
2692         int index = 0;
2693         int rate_idx;
2694         int repeat_rate = 0;
2695         u8 ant_toggle_cnt = 0;
2696         u8 use_ht_possible = 1;
2697         u8 valid_tx_ant = 0;
2698         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2699
2700         /* Override starting rate (index 0) if needed for debug purposes */
2701         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2702
2703         /* Interpret new_rate (rate_n_flags) */
2704         memset(&tbl_type, 0, sizeof(tbl_type));
2705         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2706                                   &tbl_type, &rate_idx);
2707
2708         /* How many times should we repeat the initial rate? */
2709         if (is_legacy(tbl_type.lq_type)) {
2710                 ant_toggle_cnt = 1;
2711                 repeat_rate = IWL_NUMBER_TRY;
2712         } else {
2713                 repeat_rate = IWL_HT_NUMBER_TRY;
2714         }
2715
2716         lq_cmd->general_params.mimo_delimiter =
2717                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2718
2719         /* Fill 1st table entry (index 0) */
2720         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2721
2722         if (num_of_ant(tbl_type.ant_type) == 1) {
2723                 lq_cmd->general_params.single_stream_ant_msk =
2724                                                 tbl_type.ant_type;
2725         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2726                 lq_cmd->general_params.dual_stream_ant_msk =
2727                                                 tbl_type.ant_type;
2728         } /* otherwise we don't modify the existing value */
2729
2730         index++;
2731         repeat_rate--;
2732
2733         if (priv)
2734                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2735
2736         /* Fill rest of rate table */
2737         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2738                 /* Repeat initial/next rate.
2739                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2740                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2741                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2742                         if (is_legacy(tbl_type.lq_type)) {
2743                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2744                                         ant_toggle_cnt++;
2745                                 else if (priv &&
2746                                          rs_toggle_antenna(valid_tx_ant,
2747                                                         &new_rate, &tbl_type))
2748                                         ant_toggle_cnt = 1;
2749 }
2750
2751                         /* Override next rate if needed for debug purposes */
2752                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2753
2754                         /* Fill next table entry */
2755                         lq_cmd->rs_table[index].rate_n_flags =
2756                                         cpu_to_le32(new_rate);
2757                         repeat_rate--;
2758                         index++;
2759                 }
2760
2761                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2762                                                 &rate_idx);
2763
2764                 /* Indicate to uCode which entries might be MIMO.
2765                  * If initial rate was MIMO, this will finally end up
2766                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2767                 if (is_mimo(tbl_type.lq_type))
2768                         lq_cmd->general_params.mimo_delimiter = index;
2769
2770                 /* Get next rate */
2771                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2772                                              use_ht_possible);
2773
2774                 /* How many times should we repeat the next rate? */
2775                 if (is_legacy(tbl_type.lq_type)) {
2776                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2777                                 ant_toggle_cnt++;
2778                         else if (priv &&
2779                                  rs_toggle_antenna(valid_tx_ant,
2780                                                    &new_rate, &tbl_type))
2781                                 ant_toggle_cnt = 1;
2782
2783                         repeat_rate = IWL_NUMBER_TRY;
2784                 } else {
2785                         repeat_rate = IWL_HT_NUMBER_TRY;
2786                 }
2787
2788                 /* Don't allow HT rates after next pass.
2789                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2790                 use_ht_possible = 0;
2791
2792                 /* Override next rate if needed for debug purposes */
2793                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2794
2795                 /* Fill next table entry */
2796                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2797
2798                 index++;
2799                 repeat_rate--;
2800         }
2801
2802         lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_MAX;
2803         lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2804         lq_cmd->agg_params.agg_time_limit =
2805                 cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2806 }
2807
2808 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2809 {
2810         return hw->priv;
2811 }
2812 /* rate scale requires free function to be implemented */
2813 static void rs_free(void *priv_rate)
2814 {
2815         return;
2816 }
2817
2818 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2819                         void *priv_sta)
2820 {
2821         struct iwl_lq_sta *lq_sta = priv_sta;
2822         struct iwl_priv *priv __maybe_unused = priv_r;
2823
2824         IWL_DEBUG_RATE(priv, "enter\n");
2825         kfree(lq_sta);
2826         IWL_DEBUG_RATE(priv, "leave\n");
2827 }
2828
2829
2830 #ifdef CONFIG_MAC80211_DEBUGFS
2831 static int open_file_generic(struct inode *inode, struct file *file)
2832 {
2833         file->private_data = inode->i_private;
2834         return 0;
2835 }
2836 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2837                              u32 *rate_n_flags, int index)
2838 {
2839         struct iwl_priv *priv;
2840         u8 valid_tx_ant;
2841         u8 ant_sel_tx;
2842
2843         priv = lq_sta->drv;
2844         valid_tx_ant = priv->hw_params.valid_tx_ant;
2845         if (lq_sta->dbg_fixed_rate) {
2846                 ant_sel_tx =
2847                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2848                   >> RATE_MCS_ANT_POS);
2849                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2850                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2851                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2852                 } else {
2853                         lq_sta->dbg_fixed_rate = 0;
2854                         IWL_ERR(priv,
2855                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2856                             ant_sel_tx, valid_tx_ant);
2857                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2858                 }
2859         } else {
2860                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2861         }
2862 }
2863
2864 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2865                         const char __user *user_buf, size_t count, loff_t *ppos)
2866 {
2867         struct iwl_lq_sta *lq_sta = file->private_data;
2868         struct iwl_priv *priv;
2869         char buf[64];
2870         int buf_size;
2871         u32 parsed_rate;
2872
2873         priv = lq_sta->drv;
2874         memset(buf, 0, sizeof(buf));
2875         buf_size = min(count, sizeof(buf) -  1);
2876         if (copy_from_user(buf, user_buf, buf_size))
2877                 return -EFAULT;
2878
2879         if (sscanf(buf, "%x", &parsed_rate) == 1)
2880                 lq_sta->dbg_fixed_rate = parsed_rate;
2881         else
2882                 lq_sta->dbg_fixed_rate = 0;
2883
2884         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2885         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2886         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2887         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2888
2889         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2890                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2891
2892         if (lq_sta->dbg_fixed_rate) {
2893                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2894                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2895         }
2896
2897         return count;
2898 }
2899
2900 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2901                         char __user *user_buf, size_t count, loff_t *ppos)
2902 {
2903         char *buff;
2904         int desc = 0;
2905         int i = 0;
2906         int index = 0;
2907         ssize_t ret;
2908
2909         struct iwl_lq_sta *lq_sta = file->private_data;
2910         struct iwl_priv *priv;
2911         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2912
2913         priv = lq_sta->drv;
2914         buff = kmalloc(1024, GFP_KERNEL);
2915         if (!buff)
2916                 return -ENOMEM;
2917
2918         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2919         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2920                         lq_sta->total_failed, lq_sta->total_success,
2921                         lq_sta->active_legacy_rate);
2922         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2923                         lq_sta->dbg_fixed_rate);
2924         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2925             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2926             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2927             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2928         desc += sprintf(buff+desc, "lq type %s\n",
2929            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2930         if (is_Ht(tbl->lq_type)) {
2931                 desc += sprintf(buff+desc, " %s",
2932                    (is_siso(tbl->lq_type)) ? "SISO" :
2933                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2934                    desc += sprintf(buff+desc, " %s",
2935                    (tbl->is_ht40) ? "40MHz" : "20MHz");
2936                    desc += sprintf(buff+desc, " %s %s\n", (tbl->is_SGI) ? "SGI" : "",
2937                    (lq_sta->is_green) ? "GF enabled" : "");
2938         }
2939         desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2940                 lq_sta->last_rate_n_flags);
2941         desc += sprintf(buff+desc, "general:"
2942                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2943                 lq_sta->lq.general_params.flags,
2944                 lq_sta->lq.general_params.mimo_delimiter,
2945                 lq_sta->lq.general_params.single_stream_ant_msk,
2946                 lq_sta->lq.general_params.dual_stream_ant_msk);
2947
2948         desc += sprintf(buff+desc, "agg:"
2949                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2950                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2951                         lq_sta->lq.agg_params.agg_dis_start_th,
2952                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2953
2954         desc += sprintf(buff+desc,
2955                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2956                         lq_sta->lq.general_params.start_rate_index[0],
2957                         lq_sta->lq.general_params.start_rate_index[1],
2958                         lq_sta->lq.general_params.start_rate_index[2],
2959                         lq_sta->lq.general_params.start_rate_index[3]);
2960
2961         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2962                 index = iwl_hwrate_to_plcp_idx(
2963                         le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2964                 if (is_legacy(tbl->lq_type)) {
2965                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2966                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2967                                 iwl_rate_mcs[index].mbps);
2968                 } else {
2969                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps (%s)\n",
2970                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2971                                 iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
2972                 }
2973         }
2974
2975         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2976         kfree(buff);
2977         return ret;
2978 }
2979
2980 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2981         .write = rs_sta_dbgfs_scale_table_write,
2982         .read = rs_sta_dbgfs_scale_table_read,
2983         .open = open_file_generic,
2984 };
2985 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2986                         char __user *user_buf, size_t count, loff_t *ppos)
2987 {
2988         char *buff;
2989         int desc = 0;
2990         int i, j;
2991         ssize_t ret;
2992
2993         struct iwl_lq_sta *lq_sta = file->private_data;
2994
2995         buff = kmalloc(1024, GFP_KERNEL);
2996         if (!buff)
2997                 return -ENOMEM;
2998
2999         for (i = 0; i < LQ_SIZE; i++) {
3000                 desc += sprintf(buff+desc,
3001                                 "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
3002                                 "rate=0x%X\n",
3003                                 lq_sta->active_tbl == i ? "*" : "x",
3004                                 lq_sta->lq_info[i].lq_type,
3005                                 lq_sta->lq_info[i].is_SGI,
3006                                 lq_sta->lq_info[i].is_ht40,
3007                                 lq_sta->lq_info[i].is_dup,
3008                                 lq_sta->is_green,
3009                                 lq_sta->lq_info[i].current_rate);
3010                 for (j = 0; j < IWL_RATE_COUNT; j++) {
3011                         desc += sprintf(buff+desc,
3012                                 "counter=%d success=%d %%=%d\n",
3013                                 lq_sta->lq_info[i].win[j].counter,
3014                                 lq_sta->lq_info[i].win[j].success_counter,
3015                                 lq_sta->lq_info[i].win[j].success_ratio);
3016                 }
3017         }
3018         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3019         kfree(buff);
3020         return ret;
3021 }
3022
3023 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
3024         .read = rs_sta_dbgfs_stats_table_read,
3025         .open = open_file_generic,
3026 };
3027
3028 static ssize_t rs_sta_dbgfs_rate_scale_data_read(struct file *file,
3029                         char __user *user_buf, size_t count, loff_t *ppos)
3030 {
3031         char buff[120];
3032         int desc = 0;
3033         ssize_t ret;
3034
3035         struct iwl_lq_sta *lq_sta = file->private_data;
3036         struct iwl_priv *priv;
3037         struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
3038
3039         priv = lq_sta->drv;
3040
3041         if (is_Ht(tbl->lq_type))
3042                 desc += sprintf(buff+desc,
3043                                 "Bit Rate= %d Mb/s\n",
3044                                 tbl->expected_tpt[lq_sta->last_txrate_idx]);
3045         else
3046                 desc += sprintf(buff+desc,
3047                                 "Bit Rate= %d Mb/s\n",
3048                                 iwl_rates[lq_sta->last_txrate_idx].ieee >> 1);
3049         desc += sprintf(buff+desc,
3050                         "Signal Level= %d dBm\tNoise Level= %d dBm\n",
3051                         priv->last_rx_rssi, priv->last_rx_noise);
3052         desc += sprintf(buff+desc,
3053                         "Tsf= 0x%llx\tBeacon time= 0x%08X\n",
3054                         priv->last_tsf, priv->last_beacon_time);
3055
3056         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3057         return ret;
3058 }
3059
3060 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
3061         .read = rs_sta_dbgfs_rate_scale_data_read,
3062         .open = open_file_generic,
3063 };
3064
3065 static void rs_add_debugfs(void *priv, void *priv_sta,
3066                                         struct dentry *dir)
3067 {
3068         struct iwl_lq_sta *lq_sta = priv_sta;
3069         lq_sta->rs_sta_dbgfs_scale_table_file =
3070                 debugfs_create_file("rate_scale_table", 0600, dir,
3071                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
3072         lq_sta->rs_sta_dbgfs_stats_table_file =
3073                 debugfs_create_file("rate_stats_table", 0600, dir,
3074                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
3075         lq_sta->rs_sta_dbgfs_rate_scale_data_file =
3076                 debugfs_create_file("rate_scale_data", 0600, dir,
3077                         lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
3078         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
3079                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
3080                 &lq_sta->tx_agg_tid_en);
3081
3082 }
3083
3084 static void rs_remove_debugfs(void *priv, void *priv_sta)
3085 {
3086         struct iwl_lq_sta *lq_sta = priv_sta;
3087         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
3088         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
3089         debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
3090         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
3091 }
3092 #endif
3093
3094 static struct rate_control_ops rs_ops = {
3095         .module = NULL,
3096         .name = RS_NAME,
3097         .tx_status = rs_tx_status,
3098         .get_rate = rs_get_rate,
3099         .rate_init = rs_rate_init,
3100         .alloc = rs_alloc,
3101         .free = rs_free,
3102         .alloc_sta = rs_alloc_sta,
3103         .free_sta = rs_free_sta,
3104 #ifdef CONFIG_MAC80211_DEBUGFS
3105         .add_sta_debugfs = rs_add_debugfs,
3106         .remove_sta_debugfs = rs_remove_debugfs,
3107 #endif
3108 };
3109
3110 int iwlagn_rate_control_register(void)
3111 {
3112         return ieee80211_rate_control_register(&rs_ops);
3113 }
3114
3115 void iwlagn_rate_control_unregister(void)
3116 {
3117         ieee80211_rate_control_unregister(&rs_ops);
3118 }
3119