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 time to accum history 2 seconds */
  53 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
  54
  55 static u8 rs_ht_to_legacy[] = {
  56         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  57         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  58         IWL_RATE_6M_INDEX,
  59         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
  60         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
  61         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
  62         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
  63 };
  64
  65 static const u8 ant_toggle_lookup[] = {
  66         /*ANT_NONE -> */ ANT_NONE,
  67         /*ANT_A    -> */ ANT_B,
  68         /*ANT_B    -> */ ANT_C,
  69         /*ANT_AB   -> */ ANT_BC,
  70         /*ANT_C    -> */ ANT_A,
  71         /*ANT_AC   -> */ ANT_AB,
  72         /*ANT_BC   -> */ ANT_AC,
  73         /*ANT_ABC  -> */ ANT_ABC,
  74 };
  75
  76 /**
  77  * struct iwl_rate_scale_data -- tx success history for one rate
  78  */
  79 struct iwl_rate_scale_data {
  80         u64 data;               /* bitmap of successful frames */
  81         s32 success_counter;    /* number of frames successful */
  82         s32 success_ratio;      /* per-cent * 128  */
  83         s32 counter;            /* number of frames attempted */
  84         s32 average_tpt;        /* success ratio * expected throughput */
  85         unsigned long stamp;
  86 };
  87
  88 /**
  89  * struct iwl_scale_tbl_info -- tx params and success history for all rates
  90  *
  91  * There are two of these in struct iwl_lq_sta,
  92  * one for "active", and one for "search".
  93  */
  94 struct iwl_scale_tbl_info {
  95         enum iwl_table_type lq_type;
  96         u8 ant_type;
  97         u8 is_SGI;      /* 1 = short guard interval */
  98         u8 is_fat;      /* 1 = 40 MHz channel width */
  99         u8 is_dup;      /* 1 = duplicated data streams */
 100         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
 101         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
 102         u32 current_rate;  /* rate_n_flags, uCode API format */
 103         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
 104 };
 105
 106 struct iwl_traffic_load {
 107         unsigned long time_stamp;       /* age of the oldest statistics */
 108         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
 109                                                  * slice */
 110         u32 total;                      /* total num of packets during the
 111                                          * last TID_MAX_TIME_DIFF */
 112         u8 queue_count;                 /* number of queues that has
 113                                          * been used since the last cleanup */
 114         u8 head;                        /* start of the circular buffer */
 115 };
 116
 117 /**
 118  * struct iwl_lq_sta -- driver's rate scaling private structure
 119  *
 120  * Pointer to this gets passed back and forth between driver and mac80211.
 121  */
 122 struct iwl_lq_sta {
 123         u8 active_tbl;          /* index of active table, range 0-1 */
 124         u8 enable_counter;      /* indicates HT mode */
 125         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
 126         u8 search_better_tbl;   /* 1: currently trying alternate mode */
 127         s32 last_tpt;
 128
 129         /* The following determine when to search for a new mode */
 130         u32 table_count_limit;
 131         u32 max_failure_limit;  /* # failed frames before new search */
 132         u32 max_success_limit;  /* # successful frames before new search */
 133         u32 table_count;
 134         u32 total_failed;       /* total failed frames, any/all rates */
 135         u32 total_success;      /* total successful frames, any/all rates */
 136         u32 flush_timer;        /* time staying in mode before new search */
 137
 138         u8 action_counter;      /* # mode-switch actions tried */
 139         u8 is_green;
 140         u8 is_dup;
 141         enum ieee80211_band band;
 142         u8 ibss_sta_added;
 143
 144         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
 145         u32 supp_rates;
 146         u16 active_legacy_rate;
 147         u16 active_siso_rate;
 148         u16 active_mimo2_rate;
 149         u16 active_mimo3_rate;
 150         u16 active_rate_basic;
 151
 152         struct iwl_link_quality_cmd lq;
 153         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
 154         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
 155         u8 tx_agg_tid_en;
 156 #ifdef CONFIG_MAC80211_DEBUGFS
 157         struct dentry *rs_sta_dbgfs_scale_table_file;
 158         struct dentry *rs_sta_dbgfs_stats_table_file;
 159         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
 160         u32 dbg_fixed_rate;
 161 #endif
 162         struct iwl_priv *drv;
 163
 164         /* used to be in sta_info */
 165         int last_txrate_idx;
 166 };
 167
 168 static void rs_rate_scale_perform(struct iwl_priv *priv,
 169                                    struct ieee80211_hdr *hdr,
 170                                    struct ieee80211_sta *sta,
 171                                    struct iwl_lq_sta *lq_sta);
 172 static void rs_fill_link_cmd(const struct iwl_priv *priv,
 173                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
 174
 175
 176 #ifdef CONFIG_MAC80211_DEBUGFS
 177 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 178                              u32 *rate_n_flags, int index);
 179 #else
 180 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 181                              u32 *rate_n_flags, int index)
 182 {}
 183 #endif
 184
 185 /*
 186  * Expected throughput metrics for following rates:
 187  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
 188  * "G" is the only table that supports CCK (the first 4 rates).
 189  */
 190 /*FIXME:RS:need to separate tables for MIMO2/MIMO3*/
 191 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
 192         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
 193 };
 194
 195 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
 196         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
 197 };
 198
 199 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
 200         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
 201 };
 202
 203 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
 204         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
 205 };
 206
 207 static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
 208         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
 209 };
 210
 211 static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
 212         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
 213 };
 214
 215 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
 216         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
 217 };
 218
 219 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
 220         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
 221 };
 222
 223 static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
 224         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
 225 };
 226
 227 static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
 228         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
 229 };
 230
 231 static inline u8 rs_extract_rate(u32 rate_n_flags)
 232 {
 233         return (u8)(rate_n_flags & 0xFF);
 234 }
 235
 236 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
 237 {
 238         window->data = 0;
 239         window->success_counter = 0;
 240         window->success_ratio = IWL_INVALID_VALUE;
 241         window->counter = 0;
 242         window->average_tpt = IWL_INVALID_VALUE;
 243         window->stamp = 0;
 244 }
 245
 246 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
 247 {
 248         return (ant_type & valid_antenna) == ant_type;
 249 }
 250
 251 /*
 252  *      removes the old data from the statistics. All data that is older than
 253  *      TID_MAX_TIME_DIFF, will be deleted.
 254  */
 255 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
 256 {
 257         /* The oldest age we want to keep */
 258         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
 259
 260         while (tl->queue_count &&
 261                (tl->time_stamp < oldest_time)) {
 262                 tl->total -= tl->packet_count[tl->head];
 263                 tl->packet_count[tl->head] = 0;
 264                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
 265                 tl->queue_count--;
 266                 tl->head++;
 267                 if (tl->head >= TID_QUEUE_MAX_SIZE)
 268                         tl->head = 0;
 269         }
 270 }
 271
 272 /*
 273  *      increment traffic load value for tid and also remove
 274  *      any old values if passed the certain time period
 275  */
 276 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
 277                            struct ieee80211_hdr *hdr)
 278 {
 279         u32 curr_time = jiffies_to_msecs(jiffies);
 280         u32 time_diff;
 281         s32 index;
 282         struct iwl_traffic_load *tl = NULL;
 283         u8 tid;
 284
 285         if (ieee80211_is_data_qos(hdr->frame_control)) {
 286                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 287                 tid = qc[0] & 0xf;
 288         } else
 289                 return MAX_TID_COUNT;
 290
 291         tl = &lq_data->load[tid];
 292
 293         curr_time -= curr_time % TID_ROUND_VALUE;
 294
 295         /* Happens only for the first packet. Initialize the data */
 296         if (!(tl->queue_count)) {
 297                 tl->total = 1;
 298                 tl->time_stamp = curr_time;
 299                 tl->queue_count = 1;
 300                 tl->head = 0;
 301                 tl->packet_count[0] = 1;
 302                 return MAX_TID_COUNT;
 303         }
 304
 305         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 306         index = time_diff / TID_QUEUE_CELL_SPACING;
 307
 308         /* The history is too long: remove data that is older than */
 309         /* TID_MAX_TIME_DIFF */
 310         if (index >= TID_QUEUE_MAX_SIZE)
 311                 rs_tl_rm_old_stats(tl, curr_time);
 312
 313         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
 314         tl->packet_count[index] = tl->packet_count[index] + 1;
 315         tl->total = tl->total + 1;
 316
 317         if ((index + 1) > tl->queue_count)
 318                 tl->queue_count = index + 1;
 319
 320         return tid;
 321 }
 322
 323 /*
 324         get the traffic load value for tid
 325 */
 326 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
 327 {
 328         u32 curr_time = jiffies_to_msecs(jiffies);
 329         u32 time_diff;
 330         s32 index;
 331         struct iwl_traffic_load *tl = NULL;
 332
 333         if (tid >= TID_MAX_LOAD_COUNT)
 334                 return 0;
 335
 336         tl = &(lq_data->load[tid]);
 337
 338         curr_time -= curr_time % TID_ROUND_VALUE;
 339
 340         if (!(tl->queue_count))
 341                 return 0;
 342
 343         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 344         index = time_diff / TID_QUEUE_CELL_SPACING;
 345
 346         /* The history is too long: remove data that is older than */
 347         /* TID_MAX_TIME_DIFF */
 348         if (index >= TID_QUEUE_MAX_SIZE)
 349                 rs_tl_rm_old_stats(tl, curr_time);
 350
 351         return tl->total;
 352 }
 353
 354 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
 355                                       struct iwl_lq_sta *lq_data, u8 tid,
 356                                       struct ieee80211_sta *sta)
 357 {
 358         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
 359                 IWL_DEBUG_HT("Starting Tx agg: STA: %pM tid: %d\n",
 360                                 sta->addr, tid);
 361                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
 362         }
 363 }
 364
 365 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
 366                               struct iwl_lq_sta *lq_data,
 367                               struct ieee80211_sta *sta)
 368 {
 369         if ((tid < TID_MAX_LOAD_COUNT))
 370                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 371         else if (tid == IWL_AGG_ALL_TID)
 372                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
 373                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 374 }
 375
 376 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
 377 {
 378         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
 379                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
 380                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
 381 }
 382
 383 /**
 384  * rs_collect_tx_data - Update the success/failure sliding window
 385  *
 386  * We keep a sliding window of the last 62 packets transmitted
 387  * at this rate.  window->data contains the bitmask of successful
 388  * packets.
 389  */
 390 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
 391                               int scale_index, s32 tpt, int retries,
 392                               int successes)
 393 {
 394         struct iwl_rate_scale_data *window = NULL;
 395         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 396         s32 fail_count;
 397
 398         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 399                 return -EINVAL;
 400
 401         /* Select data for current tx bit rate */
 402         window = &(windows[scale_index]);
 403
 404         /*
 405          * Keep track of only the latest 62 tx frame attempts in this rate's
 406          * history window; anything older isn't really relevant any more.
 407          * If we have filled up the sliding window, drop the oldest attempt;
 408          * if the oldest attempt (highest bit in bitmap) shows "success",
 409          * subtract "1" from the success counter (this is the main reason
 410          * we keep these bitmaps!).
 411          */
 412         while (retries > 0) {
 413                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 414
 415                         /* remove earliest */
 416                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 417
 418                         if (window->data & mask) {
 419                                 window->data &= ~mask;
 420                                 window->success_counter--;
 421                         }
 422                 }
 423
 424                 /* Increment frames-attempted counter */
 425                 window->counter++;
 426
 427                 /* Shift bitmap by one frame (throw away oldest history),
 428                  * OR in "1", and increment "success" if this
 429                  * frame was successful. */
 430                 window->data <<= 1;
 431                 if (successes > 0) {
 432                         window->success_counter++;
 433                         window->data |= 0x1;
 434                         successes--;
 435                 }
 436
 437                 retries--;
 438         }
 439
 440         /* Calculate current success ratio, avoid divide-by-0! */
 441         if (window->counter > 0)
 442                 window->success_ratio = 128 * (100 * window->success_counter)
 443                                         / window->counter;
 444         else
 445                 window->success_ratio = IWL_INVALID_VALUE;
 446
 447         fail_count = window->counter - window->success_counter;
 448
 449         /* Calculate average throughput, if we have enough history. */
 450         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 451             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 452                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 453         else
 454                 window->average_tpt = IWL_INVALID_VALUE;
 455
 456         /* Tag this window as having been updated */
 457         window->stamp = jiffies;
 458
 459         return 0;
 460 }
 461
 462 /*
 463  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 464  */
 465 /* FIXME:RS:remove this function and put the flags statically in the table */
 466 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 467                                  struct iwl_scale_tbl_info *tbl,
 468                                  int index, u8 use_green)
 469 {
 470         u32 rate_n_flags = 0;
 471
 472         if (is_legacy(tbl->lq_type)) {
 473                 rate_n_flags = iwl_rates[index].plcp;
 474                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 475                         rate_n_flags |= RATE_MCS_CCK_MSK;
 476
 477         } else if (is_Ht(tbl->lq_type)) {
 478                 if (index > IWL_LAST_OFDM_RATE) {
 479                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 480                         index = IWL_LAST_OFDM_RATE;
 481                 }
 482                 rate_n_flags = RATE_MCS_HT_MSK;
 483
 484                 if (is_siso(tbl->lq_type))
 485                         rate_n_flags |= iwl_rates[index].plcp_siso;
 486                 else if (is_mimo2(tbl->lq_type))
 487                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 488                 else
 489                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 490         } else {
 491                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 492         }
 493
 494         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 495                                                      RATE_MCS_ANT_ABC_MSK);
 496
 497         if (is_Ht(tbl->lq_type)) {
 498                 if (tbl->is_fat) {
 499                         if (tbl->is_dup)
 500                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 501                         else
 502                                 rate_n_flags |= RATE_MCS_FAT_MSK;
 503                 }
 504                 if (tbl->is_SGI)
 505                         rate_n_flags |= RATE_MCS_SGI_MSK;
 506
 507                 if (use_green) {
 508                         rate_n_flags |= RATE_MCS_GF_MSK;
 509                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 510                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 511                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 512                         }
 513                 }
 514         }
 515         return rate_n_flags;
 516 }
 517
 518 /*
 519  * Interpret uCode API's rate_n_flags format,
 520  * fill "search" or "active" tx mode table.
 521  */
 522 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 523                                     enum ieee80211_band band,
 524                                     struct iwl_scale_tbl_info *tbl,
 525                                     int *rate_idx)
 526 {
 527         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 528         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 529         u8 mcs;
 530
 531         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 532
 533         if (*rate_idx  == IWL_RATE_INVALID) {
 534                 *rate_idx = -1;
 535                 return -EINVAL;
 536         }
 537         tbl->is_SGI = 0;        /* default legacy setup */
 538         tbl->is_fat = 0;
 539         tbl->is_dup = 0;
 540         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 541         tbl->lq_type = LQ_NONE;
 542
 543         /* legacy rate format */
 544         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 545                 if (num_of_ant == 1) {
 546                         if (band == IEEE80211_BAND_5GHZ)
 547                                 tbl->lq_type = LQ_A;
 548                         else
 549                                 tbl->lq_type = LQ_G;
 550                 }
 551         /* HT rate format */
 552         } else {
 553                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 554                         tbl->is_SGI = 1;
 555
 556                 if ((rate_n_flags & RATE_MCS_FAT_MSK) ||
 557                     (rate_n_flags & RATE_MCS_DUP_MSK))
 558                         tbl->is_fat = 1;
 559
 560                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 561                         tbl->is_dup = 1;
 562
 563                 mcs = rs_extract_rate(rate_n_flags);
 564
 565                 /* SISO */
 566                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 567                         if (num_of_ant == 1)
 568                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 569                 /* MIMO2 */
 570                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 571                         if (num_of_ant == 2)
 572                                 tbl->lq_type = LQ_MIMO2;
 573                 /* MIMO3 */
 574                 } else {
 575                         if (num_of_ant == 3)
 576                                 tbl->lq_type = LQ_MIMO3;
 577                 }
 578         }
 579         return 0;
 580 }
 581
 582 /* switch to another antenna/antennas and return 1 */
 583 /* if no other valid antenna found, return 0 */
 584 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 585                              struct iwl_scale_tbl_info *tbl)
 586 {
 587         u8 new_ant_type;
 588
 589         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 590                 return 0;
 591
 592         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 593                 return 0;
 594
 595         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 596
 597         while ((new_ant_type != tbl->ant_type) &&
 598                !rs_is_valid_ant(valid_ant, new_ant_type))
 599                 new_ant_type = ant_toggle_lookup[new_ant_type];
 600
 601         if (new_ant_type == tbl->ant_type)
 602                 return 0;
 603
 604         tbl->ant_type = new_ant_type;
 605         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 606         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 607         return 1;
 608 }
 609
 610 /* FIXME:RS: in 4965 we don't use greenfield at all */
 611 /* FIXME:RS: don't use greenfield for now in TX */
 612 #if 0
 613 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
 614 {
 615         return (conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
 616                 priv->current_ht_config.is_green_field &&
 617                 !priv->current_ht_config.non_GF_STA_present;
 618 }
 619 #endif
 620 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
 621 {
 622         return 0;
 623 }
 624
 625 /**
 626  * rs_get_supported_rates - get the available rates
 627  *
 628  * if management frame or broadcast frame only return
 629  * basic available rates.
 630  *
 631  */
 632 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 633                                   struct ieee80211_hdr *hdr,
 634                                   enum iwl_table_type rate_type)
 635 {
 636         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 637             lq_sta->active_rate_basic)
 638                 return lq_sta->active_rate_basic;
 639
 640         if (is_legacy(rate_type)) {
 641                 return lq_sta->active_legacy_rate;
 642         } else {
 643                 if (is_siso(rate_type))
 644                         return lq_sta->active_siso_rate;
 645                 else if (is_mimo2(rate_type))
 646                         return lq_sta->active_mimo2_rate;
 647                 else
 648                         return lq_sta->active_mimo3_rate;
 649         }
 650 }
 651
 652 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 653                                 int rate_type)
 654 {
 655         u8 high = IWL_RATE_INVALID;
 656         u8 low = IWL_RATE_INVALID;
 657
 658         /* 802.11A or ht walks to the next literal adjacent rate in
 659          * the rate table */
 660         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 661                 int i;
 662                 u32 mask;
 663
 664                 /* Find the previous rate that is in the rate mask */
 665                 i = index - 1;
 666                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 667                         if (rate_mask & mask) {
 668                                 low = i;
 669                                 break;
 670                         }
 671                 }
 672
 673                 /* Find the next rate that is in the rate mask */
 674                 i = index + 1;
 675                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 676                         if (rate_mask & mask) {
 677                                 high = i;
 678                                 break;
 679                         }
 680                 }
 681
 682                 return (high << 8) | low;
 683         }
 684
 685         low = index;
 686         while (low != IWL_RATE_INVALID) {
 687                 low = iwl_rates[low].prev_rs;
 688                 if (low == IWL_RATE_INVALID)
 689                         break;
 690                 if (rate_mask & (1 << low))
 691                         break;
 692                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
 693         }
 694
 695         high = index;
 696         while (high != IWL_RATE_INVALID) {
 697                 high = iwl_rates[high].next_rs;
 698                 if (high == IWL_RATE_INVALID)
 699                         break;
 700                 if (rate_mask & (1 << high))
 701                         break;
 702                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
 703         }
 704
 705         return (high << 8) | low;
 706 }
 707
 708 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 709                              struct iwl_scale_tbl_info *tbl,
 710                              u8 scale_index, u8 ht_possible)
 711 {
 712         s32 low;
 713         u16 rate_mask;
 714         u16 high_low;
 715         u8 switch_to_legacy = 0;
 716         u8 is_green = lq_sta->is_green;
 717
 718         /* check if we need to switch from HT to legacy rates.
 719          * assumption is that mandatory rates (1Mbps or 6Mbps)
 720          * are always supported (spec demand) */
 721         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 722                 switch_to_legacy = 1;
 723                 scale_index = rs_ht_to_legacy[scale_index];
 724                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 725                         tbl->lq_type = LQ_A;
 726                 else
 727                         tbl->lq_type = LQ_G;
 728
 729                 if (num_of_ant(tbl->ant_type) > 1)
 730                         tbl->ant_type = ANT_A;/*FIXME:RS*/
 731
 732                 tbl->is_fat = 0;
 733                 tbl->is_SGI = 0;
 734         }
 735
 736         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 737
 738         /* Mask with station rate restriction */
 739         if (is_legacy(tbl->lq_type)) {
 740                 /* supp_rates has no CCK bits in A mode */
 741                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 742                         rate_mask  = (u16)(rate_mask &
 743                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 744                 else
 745                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 746         }
 747
 748         /* If we switched from HT to legacy, check current rate */
 749         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 750                 low = scale_index;
 751                 goto out;
 752         }
 753
 754         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 755                                         tbl->lq_type);
 756         low = high_low & 0xff;
 757
 758         if (low == IWL_RATE_INVALID)
 759                 low = scale_index;
 760
 761 out:
 762         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 763 }
 764
 765 /*
 766  * mac80211 sends us Tx status
 767  */
 768 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 769                          struct ieee80211_sta *sta, void *priv_sta,
 770                          struct sk_buff *skb)
 771 {
 772         int status;
 773         u8 retries;
 774         int rs_index, index = 0;
 775         struct iwl_lq_sta *lq_sta = priv_sta;
 776         struct iwl_link_quality_cmd *table;
 777         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 778         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 779         struct ieee80211_hw *hw = priv->hw;
 780         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 781         struct iwl_rate_scale_data *window = NULL;
 782         struct iwl_rate_scale_data *search_win = NULL;
 783         u32 tx_rate;
 784         struct iwl_scale_tbl_info tbl_type;
 785         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
 786         u8 active_index = 0;
 787         s32 tpt = 0;
 788
 789         IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
 790
 791         if (!ieee80211_is_data(hdr->frame_control) ||
 792             is_multicast_ether_addr(hdr->addr1))
 793                 return;
 794
 795         /* This packet was aggregated but doesn't carry rate scale info */
 796         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 797             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 798                 return;
 799
 800         retries = info->status.rates[0].count - 1;
 801
 802         if (retries > 15)
 803                 retries = 15;
 804
 805         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 806             !lq_sta->ibss_sta_added)
 807                 goto out;
 808
 809         table = &lq_sta->lq;
 810         active_index = lq_sta->active_tbl;
 811
 812         curr_tbl = &(lq_sta->lq_info[active_index]);
 813         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
 814         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 815         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
 816
 817         /*
 818          * Ignore this Tx frame response if its initial rate doesn't match
 819          * that of latest Link Quality command.  There may be stragglers
 820          * from a previous Link Quality command, but we're no longer interested
 821          * in those; they're either from the "active" mode while we're trying
 822          * to check "search" mode, or a prior "search" mode after we've moved
 823          * to a new "search" mode (which might become the new "active" mode).
 824          */
 825         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 826         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 827         if (priv->band == IEEE80211_BAND_5GHZ)
 828                 rs_index -= IWL_FIRST_OFDM_RATE;
 829
 830         if ((info->status.rates[0].idx < 0) ||
 831             (tbl_type.is_SGI != !!(info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)) ||
 832             (tbl_type.is_fat != !!(info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 833             (tbl_type.is_dup != !!(info->status.rates[0].flags & IEEE80211_TX_RC_DUP_DATA)) ||
 834             (tbl_type.ant_type != info->antenna_sel_tx) ||
 835             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) ||
 836             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 837             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
 838              hw->wiphy->bands[info->band]->bitrates[info->status.rates[0].idx].bitrate)) {
 839                 IWL_DEBUG_RATE("initial rate does not match 0x%x\n", tx_rate);
 840                 /* the last LQ command could failed so the LQ in ucode not
 841                  * the same in driver sync up
 842                  */
 843                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 844                 goto out;
 845         }
 846
 847         /* Update frame history window with "failure" for each Tx retry. */
 848         while (retries) {
 849                 /* Look up the rate and other info used for each tx attempt.
 850                  * Each tx attempt steps one entry deeper in the rate table. */
 851                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 852                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 853                                           &tbl_type, &rs_index);
 854
 855                 /* If type matches "search" table,
 856                  * add failure to "search" history */
 857                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
 858                     (tbl_type.ant_type == search_tbl->ant_type) &&
 859                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
 860                         if (search_tbl->expected_tpt)
 861                                 tpt = search_tbl->expected_tpt[rs_index];
 862                         else
 863                                 tpt = 0;
 864                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
 865
 866                 /* Else if type matches "current/active" table,
 867                  * add failure to "current/active" history */
 868                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 869                            (tbl_type.ant_type == curr_tbl->ant_type) &&
 870                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 871                         if (curr_tbl->expected_tpt)
 872                                 tpt = curr_tbl->expected_tpt[rs_index];
 873                         else
 874                                 tpt = 0;
 875                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
 876                 }
 877
 878                 /* If not searching for a new mode, increment failed counter
 879                  * ... this helps determine when to start searching again */
 880                 if (lq_sta->stay_in_tbl)
 881                         lq_sta->total_failed++;
 882                 --retries;
 883                 index++;
 884
 885         }
 886
 887         /*
 888          * Find (by rate) the history window to update with final Tx attempt;
 889          * if Tx was successful first try, use original rate,
 890          * else look up the rate that was, finally, successful.
 891          */
 892         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 893         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 894
 895         /* Update frame history window with "success" if Tx got ACKed ... */
 896         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
 897
 898         /* If type matches "search" table,
 899          * add final tx status to "search" history */
 900         if ((tbl_type.lq_type == search_tbl->lq_type) &&
 901             (tbl_type.ant_type == search_tbl->ant_type) &&
 902             (tbl_type.is_SGI == search_tbl->is_SGI)) {
 903                 if (search_tbl->expected_tpt)
 904                         tpt = search_tbl->expected_tpt[rs_index];
 905                 else
 906                         tpt = 0;
 907                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
 908                         rs_collect_tx_data(search_win, rs_index, tpt,
 909                                            info->status.ampdu_ack_len,
 910                                            info->status.ampdu_ack_map);
 911                 else
 912                         rs_collect_tx_data(search_win, rs_index, tpt,
 913                                            1, status);
 914         /* Else if type matches "current/active" table,
 915          * add final tx status to "current/active" history */
 916         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 917                    (tbl_type.ant_type == curr_tbl->ant_type) &&
 918                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 919                 if (curr_tbl->expected_tpt)
 920                         tpt = curr_tbl->expected_tpt[rs_index];
 921                 else
 922                         tpt = 0;
 923                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
 924                         rs_collect_tx_data(window, rs_index, tpt,
 925                                            info->status.ampdu_ack_len,
 926                                            info->status.ampdu_ack_map);
 927                 else
 928                         rs_collect_tx_data(window, rs_index, tpt,
 929                                            1, status);
 930         }
 931
 932         /* If not searching for new mode, increment success/failed counter
 933          * ... these help determine when to start searching again */
 934         if (lq_sta->stay_in_tbl) {
 935                 if (info->flags & IEEE80211_TX_CTL_AMPDU) {
 936                         lq_sta->total_success += info->status.ampdu_ack_map;
 937                         lq_sta->total_failed +=
 938                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
 939                 } else {
 940                         if (status)
 941                                 lq_sta->total_success++;
 942                         else
 943                                 lq_sta->total_failed++;
 944                 }
 945         }
 946
 947         /* See if there's a better rate or modulation mode to try. */
 948         if (sta && sta->supp_rates[sband->band])
 949                 rs_rate_scale_perform(priv, hdr, sta, lq_sta);
 950 out:
 951         return;
 952 }
 953
 954 /*
 955  * Begin a period of staying with a selected modulation mode.
 956  * Set "stay_in_tbl" flag to prevent any mode switches.
 957  * Set frame tx success limits according to legacy vs. high-throughput,
 958  * and reset overall (spanning all rates) tx success history statistics.
 959  * These control how long we stay using same modulation mode before
 960  * searching for a new mode.
 961  */
 962 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
 963                                  struct iwl_lq_sta *lq_sta)
 964 {
 965         IWL_DEBUG_RATE("we are staying in the same table\n");
 966         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
 967         if (is_legacy) {
 968                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
 969                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
 970                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
 971         } else {
 972                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
 973                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
 974                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
 975         }
 976         lq_sta->table_count = 0;
 977         lq_sta->total_failed = 0;
 978         lq_sta->total_success = 0;
 979 }
 980
 981 /*
 982  * Find correct throughput table for given mode of modulation
 983  */
 984 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
 985                                       struct iwl_scale_tbl_info *tbl)
 986 {
 987         if (is_legacy(tbl->lq_type)) {
 988                 if (!is_a_band(tbl->lq_type))
 989                         tbl->expected_tpt = expected_tpt_G;
 990                 else
 991                         tbl->expected_tpt = expected_tpt_A;
 992         } else if (is_siso(tbl->lq_type)) {
 993                 if (tbl->is_fat && !lq_sta->is_dup)
 994                         if (tbl->is_SGI)
 995                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
 996                         else
 997                                 tbl->expected_tpt = expected_tpt_siso40MHz;
 998                 else if (tbl->is_SGI)
 999                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1000                 else
1001                         tbl->expected_tpt = expected_tpt_siso20MHz;
1002
1003         } else if (is_mimo(tbl->lq_type)) { /* FIXME:need to separate mimo2/3 */
1004                 if (tbl->is_fat && !lq_sta->is_dup)
1005                         if (tbl->is_SGI)
1006                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
1007                         else
1008                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
1009                 else if (tbl->is_SGI)
1010                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
1011                 else
1012                         tbl->expected_tpt = expected_tpt_mimo20MHz;
1013         } else
1014                 tbl->expected_tpt = expected_tpt_G;
1015 }
1016
1017 /*
1018  * Find starting rate for new "search" high-throughput mode of modulation.
1019  * Goal is to find lowest expected rate (under perfect conditions) that is
1020  * above the current measured throughput of "active" mode, to give new mode
1021  * a fair chance to prove itself without too many challenges.
1022  *
1023  * This gets called when transitioning to more aggressive modulation
1024  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1025  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1026  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1027  * bit rate will typically need to increase, but not if performance was bad.
1028  */
1029 static s32 rs_get_best_rate(struct iwl_priv *priv,
1030                             struct iwl_lq_sta *lq_sta,
1031                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1032                             u16 rate_mask, s8 index)
1033 {
1034         /* "active" values */
1035         struct iwl_scale_tbl_info *active_tbl =
1036             &(lq_sta->lq_info[lq_sta->active_tbl]);
1037         s32 active_sr = active_tbl->win[index].success_ratio;
1038         s32 active_tpt = active_tbl->expected_tpt[index];
1039
1040         /* expected "search" throughput */
1041         s32 *tpt_tbl = tbl->expected_tpt;
1042
1043         s32 new_rate, high, low, start_hi;
1044         u16 high_low;
1045         s8 rate = index;
1046
1047         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1048
1049         for (; ;) {
1050                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1051                                                 tbl->lq_type);
1052
1053                 low = high_low & 0xff;
1054                 high = (high_low >> 8) & 0xff;
1055
1056                 /*
1057                  * Lower the "search" bit rate, to give new "search" mode
1058                  * approximately the same throughput as "active" if:
1059                  *
1060                  * 1) "Active" mode has been working modestly well (but not
1061                  *    great), and expected "search" throughput (under perfect
1062                  *    conditions) at candidate rate is above the actual
1063                  *    measured "active" throughput (but less than expected
1064                  *    "active" throughput under perfect conditions).
1065                  * OR
1066                  * 2) "Active" mode has been working perfectly or very well
1067                  *    and expected "search" throughput (under perfect
1068                  *    conditions) at candidate rate is above expected
1069                  *    "active" throughput (under perfect conditions).
1070                  */
1071                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1072                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1073                       (active_sr <= IWL_RATE_HIGH_TH) &&
1074                       (tpt_tbl[rate] <= active_tpt))) ||
1075                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1076                      (tpt_tbl[rate] > active_tpt))) {
1077
1078                         /* (2nd or later pass)
1079                          * If we've already tried to raise the rate, and are
1080                          * now trying to lower it, use the higher rate. */
1081                         if (start_hi != IWL_RATE_INVALID) {
1082                                 new_rate = start_hi;
1083                                 break;
1084                         }
1085
1086                         new_rate = rate;
1087
1088                         /* Loop again with lower rate */
1089                         if (low != IWL_RATE_INVALID)
1090                                 rate = low;
1091
1092                         /* Lower rate not available, use the original */
1093                         else
1094                                 break;
1095
1096                 /* Else try to raise the "search" rate to match "active" */
1097                 } else {
1098                         /* (2nd or later pass)
1099                          * If we've already tried to lower the rate, and are
1100                          * now trying to raise it, use the lower rate. */
1101                         if (new_rate != IWL_RATE_INVALID)
1102                                 break;
1103
1104                         /* Loop again with higher rate */
1105                         else if (high != IWL_RATE_INVALID) {
1106                                 start_hi = high;
1107                                 rate = high;
1108
1109                         /* Higher rate not available, use the original */
1110                         } else {
1111                                 new_rate = rate;
1112                                 break;
1113                         }
1114                 }
1115         }
1116
1117         return new_rate;
1118 }
1119
1120 /*
1121  * Set up search table for MIMO
1122  */
1123 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1124                              struct iwl_lq_sta *lq_sta,
1125                              struct ieee80211_conf *conf,
1126                              struct ieee80211_sta *sta,
1127                              struct iwl_scale_tbl_info *tbl, int index)
1128 {
1129         u16 rate_mask;
1130         s32 rate;
1131         s8 is_green = lq_sta->is_green;
1132
1133         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1134                 return -1;
1135
1136         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1137                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1138                 return -1;
1139
1140         /* Need both Tx chains/antennas to support MIMO */
1141         if (priv->hw_params.tx_chains_num < 2)
1142                 return -1;
1143
1144         IWL_DEBUG_RATE("LQ: try to switch to MIMO2\n");
1145
1146         tbl->lq_type = LQ_MIMO2;
1147         tbl->is_dup = lq_sta->is_dup;
1148         tbl->action = 0;
1149         rate_mask = lq_sta->active_mimo2_rate;
1150
1151         if (priv->current_ht_config.supported_chan_width
1152                                         == IWL_CHANNEL_WIDTH_40MHZ)
1153                 tbl->is_fat = 1;
1154         else
1155                 tbl->is_fat = 0;
1156
1157         /* FIXME: - don't toggle SGI here
1158         if (tbl->is_fat) {
1159                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1160                         tbl->is_SGI = 1;
1161                 else
1162                         tbl->is_SGI = 0;
1163         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1164                 tbl->is_SGI = 1;
1165         else
1166                 tbl->is_SGI = 0;
1167         */
1168
1169         rs_set_expected_tpt_table(lq_sta, tbl);
1170
1171         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1172
1173         IWL_DEBUG_RATE("LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1174
1175         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1176                 IWL_DEBUG_RATE("Can't switch with index %d rate mask %x\n",
1177                                                 rate, rate_mask);
1178                 return -1;
1179         }
1180         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1181
1182         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1183                      tbl->current_rate, is_green);
1184         return 0;
1185 }
1186
1187 /*
1188  * Set up search table for SISO
1189  */
1190 static int rs_switch_to_siso(struct iwl_priv *priv,
1191                              struct iwl_lq_sta *lq_sta,
1192                              struct ieee80211_conf *conf,
1193                              struct ieee80211_sta *sta,
1194                              struct iwl_scale_tbl_info *tbl, int index)
1195 {
1196         u16 rate_mask;
1197         u8 is_green = lq_sta->is_green;
1198         s32 rate;
1199
1200         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1201                 return -1;
1202
1203         IWL_DEBUG_RATE("LQ: try to switch to SISO\n");
1204
1205         tbl->is_dup = lq_sta->is_dup;
1206         tbl->lq_type = LQ_SISO;
1207         tbl->action = 0;
1208         rate_mask = lq_sta->active_siso_rate;
1209
1210         if (priv->current_ht_config.supported_chan_width
1211             == IWL_CHANNEL_WIDTH_40MHZ)
1212                 tbl->is_fat = 1;
1213         else
1214                 tbl->is_fat = 0;
1215
1216         /* FIXME: - don't toggle SGI here
1217         if (tbl->is_fat) {
1218                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1219                         tbl->is_SGI = 1;
1220                 else
1221                         tbl->is_SGI = 0;
1222         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1223                 tbl->is_SGI = 1;
1224         else
1225                 tbl->is_SGI = 0;
1226         */
1227
1228         if (is_green)
1229                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1230
1231         rs_set_expected_tpt_table(lq_sta, tbl);
1232         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1233
1234         IWL_DEBUG_RATE("LQ: get best rate %d mask %X\n", rate, rate_mask);
1235         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1236                 IWL_DEBUG_RATE("can not switch with index %d rate mask %x\n",
1237                              rate, rate_mask);
1238                 return -1;
1239         }
1240         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1241         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1242                      tbl->current_rate, is_green);
1243         return 0;
1244 }
1245
1246 /*
1247  * Try to switch to new modulation mode from legacy
1248  */
1249 static int rs_move_legacy_other(struct iwl_priv *priv,
1250                                 struct iwl_lq_sta *lq_sta,
1251                                 struct ieee80211_conf *conf,
1252                                 struct ieee80211_sta *sta,
1253                                 int index)
1254 {
1255         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1256         struct iwl_scale_tbl_info *search_tbl =
1257                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1258         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1259         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1260                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1261         u8 start_action = tbl->action;
1262         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1263         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1264         int ret = 0;
1265
1266         for (; ;) {
1267                 switch (tbl->action) {
1268                 case IWL_LEGACY_SWITCH_ANTENNA1:
1269                 case IWL_LEGACY_SWITCH_ANTENNA2:
1270                         IWL_DEBUG_RATE("LQ: Legacy toggle Antenna\n");
1271
1272                         lq_sta->action_counter++;
1273
1274                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1275                                                         tx_chains_num <= 1) ||
1276                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1277                                                         tx_chains_num <= 2))
1278                                 break;
1279
1280                         /* Don't change antenna if success has been great */
1281                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1282                                 break;
1283
1284                         /* Set up search table to try other antenna */
1285                         memcpy(search_tbl, tbl, sz);
1286
1287                         if (rs_toggle_antenna(valid_tx_ant,
1288                                 &search_tbl->current_rate, search_tbl)) {
1289                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1290                                 goto out;
1291                         }
1292                         break;
1293                 case IWL_LEGACY_SWITCH_SISO:
1294                         IWL_DEBUG_RATE("LQ: Legacy switch to SISO\n");
1295
1296                         /* Set up search table to try SISO */
1297                         memcpy(search_tbl, tbl, sz);
1298                         search_tbl->is_SGI = 0;
1299                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1300                                                  search_tbl, index);
1301                         if (!ret) {
1302                                 lq_sta->action_counter = 0;
1303                                 goto out;
1304                         }
1305
1306                         break;
1307                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1308                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1309                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1310                         IWL_DEBUG_RATE("LQ: Legacy switch to MIMO2\n");
1311
1312                         /* Set up search table to try MIMO */
1313                         memcpy(search_tbl, tbl, sz);
1314                         search_tbl->is_SGI = 0;
1315
1316                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1317                                 search_tbl->ant_type = ANT_AB;
1318                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1319                                 search_tbl->ant_type = ANT_AC;
1320                         else
1321                                 search_tbl->ant_type = ANT_BC;
1322
1323                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1324                                 break;
1325
1326                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1327                                                  search_tbl, index);
1328                         if (!ret) {
1329                                 lq_sta->action_counter = 0;
1330                                 goto out;
1331                         }
1332                         break;
1333                 }
1334                 tbl->action++;
1335                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1336                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1337
1338                 if (tbl->action == start_action)
1339                         break;
1340
1341         }
1342         search_tbl->lq_type = LQ_NONE;
1343         return 0;
1344
1345 out:
1346         lq_sta->search_better_tbl = 1;
1347         tbl->action++;
1348         if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1349                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1350         return 0;
1351
1352 }
1353
1354 /*
1355  * Try to switch to new modulation mode from SISO
1356  */
1357 static int rs_move_siso_to_other(struct iwl_priv *priv,
1358                                  struct iwl_lq_sta *lq_sta,
1359                                  struct ieee80211_conf *conf,
1360                                  struct ieee80211_sta *sta, int index)
1361 {
1362         u8 is_green = lq_sta->is_green;
1363         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1364         struct iwl_scale_tbl_info *search_tbl =
1365                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1366         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1367         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1368                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1369         u8 start_action = tbl->action;
1370         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1371         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1372         int ret;
1373
1374         for (;;) {
1375                 lq_sta->action_counter++;
1376                 switch (tbl->action) {
1377                 case IWL_SISO_SWITCH_ANTENNA1:
1378                 case IWL_SISO_SWITCH_ANTENNA2:
1379                         IWL_DEBUG_RATE("LQ: SISO toggle Antenna\n");
1380
1381                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1382                                                         tx_chains_num <= 1) ||
1383                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1384                                                         tx_chains_num <= 2))
1385                                 break;
1386
1387                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1388                                 break;
1389
1390                         memcpy(search_tbl, tbl, sz);
1391                         if (rs_toggle_antenna(valid_tx_ant,
1392                                        &search_tbl->current_rate, search_tbl))
1393                                 goto out;
1394                         break;
1395                 case IWL_SISO_SWITCH_MIMO2_AB:
1396                 case IWL_SISO_SWITCH_MIMO2_AC:
1397                 case IWL_SISO_SWITCH_MIMO2_BC:
1398                         IWL_DEBUG_RATE("LQ: SISO switch to MIMO2\n");
1399                         memcpy(search_tbl, tbl, sz);
1400                         search_tbl->is_SGI = 0;
1401
1402                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1403                                 search_tbl->ant_type = ANT_AB;
1404                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1405                                 search_tbl->ant_type = ANT_AC;
1406                         else
1407                                 search_tbl->ant_type = ANT_BC;
1408
1409                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1410                                 break;
1411
1412                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1413                                                  search_tbl, index);
1414                         if (!ret)
1415                                 goto out;
1416                         break;
1417                 case IWL_SISO_SWITCH_GI:
1418                         if (!tbl->is_fat &&
1419                                 !(priv->current_ht_config.sgf &
1420                                                 HT_SHORT_GI_20MHZ))
1421                                 break;
1422                         if (tbl->is_fat &&
1423                                 !(priv->current_ht_config.sgf &
1424                                                 HT_SHORT_GI_40MHZ))
1425                                 break;
1426
1427                         IWL_DEBUG_RATE("LQ: SISO toggle SGI/NGI\n");
1428
1429                         memcpy(search_tbl, tbl, sz);
1430                         if (is_green) {
1431                                 if (!tbl->is_SGI)
1432                                         break;
1433                                 else
1434                                         IWL_ERR(priv,
1435                                                 "SGI was set in GF+SISO\n");
1436                         }
1437                         search_tbl->is_SGI = !tbl->is_SGI;
1438                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1439                         if (tbl->is_SGI) {
1440                                 s32 tpt = lq_sta->last_tpt / 100;
1441                                 if (tpt >= search_tbl->expected_tpt[index])
1442                                         break;
1443                         }
1444                         search_tbl->current_rate =
1445                                 rate_n_flags_from_tbl(priv, search_tbl,
1446                                                       index, is_green);
1447                         goto out;
1448                 }
1449                 tbl->action++;
1450                 if (tbl->action > IWL_SISO_SWITCH_GI)
1451                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1452
1453                 if (tbl->action == start_action)
1454                         break;
1455         }
1456         search_tbl->lq_type = LQ_NONE;
1457         return 0;
1458
1459  out:
1460         lq_sta->search_better_tbl = 1;
1461         tbl->action++;
1462         if (tbl->action > IWL_SISO_SWITCH_GI)
1463                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1464         return 0;
1465 }
1466
1467 /*
1468  * Try to switch to new modulation mode from MIMO
1469  */
1470 static int rs_move_mimo_to_other(struct iwl_priv *priv,
1471                                  struct iwl_lq_sta *lq_sta,
1472                                  struct ieee80211_conf *conf,
1473                                  struct ieee80211_sta *sta, int index)
1474 {
1475         s8 is_green = lq_sta->is_green;
1476         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1477         struct iwl_scale_tbl_info *search_tbl =
1478                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1479         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1480         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1481                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1482         u8 start_action = tbl->action;
1483         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1484         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1485         int ret;
1486
1487         for (;;) {
1488                 lq_sta->action_counter++;
1489                 switch (tbl->action) {
1490                 case IWL_MIMO2_SWITCH_ANTENNA1:
1491                 case IWL_MIMO2_SWITCH_ANTENNA2:
1492                         IWL_DEBUG_RATE("LQ: MIMO toggle Antennas\n");
1493
1494                         if (tx_chains_num <= 2)
1495                                 break;
1496
1497                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1498                                 break;
1499
1500                         memcpy(search_tbl, tbl, sz);
1501                         if (rs_toggle_antenna(valid_tx_ant,
1502                                        &search_tbl->current_rate, search_tbl))
1503                                 goto out;
1504                         break;
1505                 case IWL_MIMO2_SWITCH_SISO_A:
1506                 case IWL_MIMO2_SWITCH_SISO_B:
1507                 case IWL_MIMO2_SWITCH_SISO_C:
1508                         IWL_DEBUG_RATE("LQ: MIMO2 switch to SISO\n");
1509
1510                         /* Set up new search table for SISO */
1511                         memcpy(search_tbl, tbl, sz);
1512
1513                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1514                                 search_tbl->ant_type = ANT_A;
1515                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1516                                 search_tbl->ant_type = ANT_B;
1517                         else
1518                                 search_tbl->ant_type = ANT_C;
1519
1520                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1521                                 break;
1522
1523                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1524                                                  search_tbl, index);
1525                         if (!ret)
1526                                 goto out;
1527
1528                         break;
1529
1530                 case IWL_MIMO2_SWITCH_GI:
1531                         if (!tbl->is_fat &&
1532                                 !(priv->current_ht_config.sgf &
1533                                                 HT_SHORT_GI_20MHZ))
1534                                 break;
1535                         if (tbl->is_fat &&
1536                                 !(priv->current_ht_config.sgf &
1537                                                 HT_SHORT_GI_40MHZ))
1538                                 break;
1539
1540                         IWL_DEBUG_RATE("LQ: MIMO toggle SGI/NGI\n");
1541
1542                         /* Set up new search table for MIMO */
1543                         memcpy(search_tbl, tbl, sz);
1544                         search_tbl->is_SGI = !tbl->is_SGI;
1545                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1546                         /*
1547                          * If active table already uses the fastest possible
1548                          * modulation (dual stream with short guard interval),
1549                          * and it's working well, there's no need to look
1550                          * for a better type of modulation!
1551                          */
1552                         if (tbl->is_SGI) {
1553                                 s32 tpt = lq_sta->last_tpt / 100;
1554                                 if (tpt >= search_tbl->expected_tpt[index])
1555                                         break;
1556                         }
1557                         search_tbl->current_rate =
1558                                 rate_n_flags_from_tbl(priv, search_tbl,
1559                                                       index, is_green);
1560                         goto out;
1561
1562                 }
1563                 tbl->action++;
1564                 if (tbl->action > IWL_MIMO2_SWITCH_GI)
1565                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1566
1567                 if (tbl->action == start_action)
1568                         break;
1569         }
1570         search_tbl->lq_type = LQ_NONE;
1571         return 0;
1572  out:
1573         lq_sta->search_better_tbl = 1;
1574         tbl->action++;
1575         if (tbl->action > IWL_MIMO2_SWITCH_GI)
1576                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1577         return 0;
1578
1579 }
1580
1581 /*
1582  * Check whether we should continue using same modulation mode, or
1583  * begin search for a new mode, based on:
1584  * 1) # tx successes or failures while using this mode
1585  * 2) # times calling this function
1586  * 3) elapsed time in this mode (not used, for now)
1587  */
1588 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1589 {
1590         struct iwl_scale_tbl_info *tbl;
1591         int i;
1592         int active_tbl;
1593         int flush_interval_passed = 0;
1594         struct iwl_priv *priv;
1595
1596         priv = lq_sta->drv;
1597         active_tbl = lq_sta->active_tbl;
1598
1599         tbl = &(lq_sta->lq_info[active_tbl]);
1600
1601         /* If we've been disallowing search, see if we should now allow it */
1602         if (lq_sta->stay_in_tbl) {
1603
1604                 /* Elapsed time using current modulation mode */
1605                 if (lq_sta->flush_timer)
1606                         flush_interval_passed =
1607                             time_after(jiffies,
1608                                        (unsigned long)(lq_sta->flush_timer +
1609                                         IWL_RATE_SCALE_FLUSH_INTVL));
1610
1611                 /*
1612                  * Check if we should allow search for new modulation mode.
1613                  * If many frames have failed or succeeded, or we've used
1614                  * this same modulation for a long time, allow search, and
1615                  * reset history stats that keep track of whether we should
1616                  * allow a new search.  Also (below) reset all bitmaps and
1617                  * stats in active history.
1618                  */
1619                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1620                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1621                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1622                      && (flush_interval_passed))) {
1623                         IWL_DEBUG_RATE("LQ: stay is expired %d %d %d\n:",
1624                                      lq_sta->total_failed,
1625                                      lq_sta->total_success,
1626                                      flush_interval_passed);
1627
1628                         /* Allow search for new mode */
1629                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1630                         lq_sta->total_failed = 0;
1631                         lq_sta->total_success = 0;
1632                         lq_sta->flush_timer = 0;
1633
1634                 /*
1635                  * Else if we've used this modulation mode enough repetitions
1636                  * (regardless of elapsed time or success/failure), reset
1637                  * history bitmaps and rate-specific stats for all rates in
1638                  * active table.
1639                  */
1640                 } else {
1641                         lq_sta->table_count++;
1642                         if (lq_sta->table_count >=
1643                             lq_sta->table_count_limit) {
1644                                 lq_sta->table_count = 0;
1645
1646                                 IWL_DEBUG_RATE("LQ: stay in table clear win\n");
1647                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1648                                         rs_rate_scale_clear_window(
1649                                                 &(tbl->win[i]));
1650                         }
1651                 }
1652
1653                 /* If transitioning to allow "search", reset all history
1654                  * bitmaps and stats in active table (this will become the new
1655                  * "search" table). */
1656                 if (!lq_sta->stay_in_tbl) {
1657                         for (i = 0; i < IWL_RATE_COUNT; i++)
1658                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1659                 }
1660         }
1661 }
1662
1663 /*
1664  * Do rate scaling and search for new modulation mode.
1665  */
1666 static void rs_rate_scale_perform(struct iwl_priv *priv,
1667                                   struct ieee80211_hdr *hdr,
1668                                   struct ieee80211_sta *sta,
1669                                   struct iwl_lq_sta *lq_sta)
1670 {
1671         struct ieee80211_hw *hw = priv->hw;
1672         struct ieee80211_conf *conf = &hw->conf;
1673         int low = IWL_RATE_INVALID;
1674         int high = IWL_RATE_INVALID;
1675         int index;
1676         int i;
1677         struct iwl_rate_scale_data *window = NULL;
1678         int current_tpt = IWL_INVALID_VALUE;
1679         int low_tpt = IWL_INVALID_VALUE;
1680         int high_tpt = IWL_INVALID_VALUE;
1681         u32 fail_count;
1682         s8 scale_action = 0;
1683         u16 rate_mask;
1684         u8 update_lq = 0;
1685         struct iwl_scale_tbl_info *tbl, *tbl1;
1686         u16 rate_scale_index_msk = 0;
1687         u32 rate;
1688         u8 is_green = 0;
1689         u8 active_tbl = 0;
1690         u8 done_search = 0;
1691         u16 high_low;
1692         s32 sr;
1693         u8 tid = MAX_TID_COUNT;
1694
1695         IWL_DEBUG_RATE("rate scale calculate new rate for skb\n");
1696
1697         /* Send management frames and broadcast/multicast data using
1698          * lowest rate. */
1699         /* TODO: this could probably be improved.. */
1700         if (!ieee80211_is_data(hdr->frame_control) ||
1701             is_multicast_ether_addr(hdr->addr1))
1702                 return;
1703
1704         if (!sta || !lq_sta)
1705                 return;
1706
1707         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1708
1709         tid = rs_tl_add_packet(lq_sta, hdr);
1710
1711         /*
1712          * Select rate-scale / modulation-mode table to work with in
1713          * the rest of this function:  "search" if searching for better
1714          * modulation mode, or "active" if doing rate scaling within a mode.
1715          */
1716         if (!lq_sta->search_better_tbl)
1717                 active_tbl = lq_sta->active_tbl;
1718         else
1719                 active_tbl = 1 - lq_sta->active_tbl;
1720
1721         tbl = &(lq_sta->lq_info[active_tbl]);
1722         is_green = lq_sta->is_green;
1723
1724         /* current tx rate */
1725         index = lq_sta->last_txrate_idx;
1726
1727         IWL_DEBUG_RATE("Rate scale index %d for type %d\n", index,
1728                        tbl->lq_type);
1729
1730         /* rates available for this association, and for modulation mode */
1731         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1732
1733         IWL_DEBUG_RATE("mask 0x%04X \n", rate_mask);
1734
1735         /* mask with station rate restriction */
1736         if (is_legacy(tbl->lq_type)) {
1737                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
1738                         /* supp_rates has no CCK bits in A mode */
1739                         rate_scale_index_msk = (u16) (rate_mask &
1740                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1741                 else
1742                         rate_scale_index_msk = (u16) (rate_mask &
1743                                                       lq_sta->supp_rates);
1744
1745         } else
1746                 rate_scale_index_msk = rate_mask;
1747
1748         if (!rate_scale_index_msk)
1749                 rate_scale_index_msk = rate_mask;
1750
1751         if (!((1 << index) & rate_scale_index_msk)) {
1752                 IWL_ERR(priv, "Current Rate is not valid\n");
1753                 return;
1754         }
1755
1756         /* Get expected throughput table and history window for current rate */
1757         if (!tbl->expected_tpt) {
1758                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
1759                 return;
1760         }
1761
1762         window = &(tbl->win[index]);
1763
1764         /*
1765          * If there is not enough history to calculate actual average
1766          * throughput, keep analyzing results of more tx frames, without
1767          * changing rate or mode (bypass most of the rest of this function).
1768          * Set up new rate table in uCode only if old rate is not supported
1769          * in current association (use new rate found above).
1770          */
1771         fail_count = window->counter - window->success_counter;
1772         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1773                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
1774                 IWL_DEBUG_RATE("LQ: still below TH. succ=%d total=%d "
1775                                "for index %d\n",
1776                                window->success_counter, window->counter, index);
1777
1778                 /* Can't calculate this yet; not enough history */
1779                 window->average_tpt = IWL_INVALID_VALUE;
1780
1781                 /* Should we stay with this modulation mode,
1782                  * or search for a new one? */
1783                 rs_stay_in_table(lq_sta);
1784
1785                 goto out;
1786         }
1787
1788         /* Else we have enough samples; calculate estimate of
1789          * actual average throughput */
1790
1791         BUG_ON(window->average_tpt != ((window->success_ratio *
1792                         tbl->expected_tpt[index] + 64) / 128));
1793
1794         /* If we are searching for better modulation mode, check success. */
1795         if (lq_sta->search_better_tbl) {
1796
1797                 /* If good success, continue using the "search" mode;
1798                  * no need to send new link quality command, since we're
1799                  * continuing to use the setup that we've been trying. */
1800                 if (window->average_tpt > lq_sta->last_tpt) {
1801
1802                         IWL_DEBUG_RATE("LQ: SWITCHING TO NEW TABLE "
1803                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1804                                         window->success_ratio,
1805                                         window->average_tpt,
1806                                         lq_sta->last_tpt);
1807
1808                         if (!is_legacy(tbl->lq_type))
1809                                 lq_sta->enable_counter = 1;
1810
1811                         /* Swap tables; "search" becomes "active" */
1812                         lq_sta->active_tbl = active_tbl;
1813                         current_tpt = window->average_tpt;
1814
1815                 /* Else poor success; go back to mode in "active" table */
1816                 } else {
1817
1818                         IWL_DEBUG_RATE("LQ: GOING BACK TO THE OLD TABLE "
1819                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1820                                         window->success_ratio,
1821                                         window->average_tpt,
1822                                         lq_sta->last_tpt);
1823
1824                         /* Nullify "search" table */
1825                         tbl->lq_type = LQ_NONE;
1826
1827                         /* Revert to "active" table */
1828                         active_tbl = lq_sta->active_tbl;
1829                         tbl = &(lq_sta->lq_info[active_tbl]);
1830
1831                         /* Revert to "active" rate and throughput info */
1832                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1833                         current_tpt = lq_sta->last_tpt;
1834
1835                         /* Need to set up a new rate table in uCode */
1836                         update_lq = 1;
1837                 }
1838
1839                 /* Either way, we've made a decision; modulation mode
1840                  * search is done, allow rate adjustment next time. */
1841                 lq_sta->search_better_tbl = 0;
1842                 done_search = 1;        /* Don't switch modes below! */
1843                 goto lq_update;
1844         }
1845
1846         /* (Else) not in search of better modulation mode, try for better
1847          * starting rate, while staying in this mode. */
1848         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
1849                                         tbl->lq_type);
1850         low = high_low & 0xff;
1851         high = (high_low >> 8) & 0xff;
1852
1853         sr = window->success_ratio;
1854
1855         /* Collect measured throughputs for current and adjacent rates */
1856         current_tpt = window->average_tpt;
1857         if (low != IWL_RATE_INVALID)
1858                 low_tpt = tbl->win[low].average_tpt;
1859         if (high != IWL_RATE_INVALID)
1860                 high_tpt = tbl->win[high].average_tpt;
1861
1862         scale_action = 0;
1863
1864         /* Too many failures, decrease rate */
1865         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
1866                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
1867                 scale_action = -1;
1868
1869         /* No throughput measured yet for adjacent rates; try increase. */
1870         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1871                    (high_tpt == IWL_INVALID_VALUE)) {
1872
1873                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
1874                         scale_action = 1;
1875                 else if (low != IWL_RATE_INVALID)
1876                         scale_action = -1;
1877         }
1878
1879         /* Both adjacent throughputs are measured, but neither one has better
1880          * throughput; we're using the best rate, don't change it! */
1881         else if ((low_tpt != IWL_INVALID_VALUE) &&
1882                  (high_tpt != IWL_INVALID_VALUE) &&
1883                  (low_tpt < current_tpt) &&
1884                  (high_tpt < current_tpt))
1885                 scale_action = 0;
1886
1887         /* At least one adjacent rate's throughput is measured,
1888          * and may have better performance. */
1889         else {
1890                 /* Higher adjacent rate's throughput is measured */
1891                 if (high_tpt != IWL_INVALID_VALUE) {
1892                         /* Higher rate has better throughput */
1893                         if (high_tpt > current_tpt &&
1894                                         sr >= IWL_RATE_INCREASE_TH) {
1895                                 scale_action = 1;
1896                         } else {
1897                                 IWL_DEBUG_RATE
1898                                     ("decrease rate because of high tpt\n");
1899                                 scale_action = -1;
1900                         }
1901
1902                 /* Lower adjacent rate's throughput is measured */
1903                 } else if (low_tpt != IWL_INVALID_VALUE) {
1904                         /* Lower rate has better throughput */
1905                         if (low_tpt > current_tpt) {
1906                                 IWL_DEBUG_RATE
1907                                     ("decrease rate because of low tpt\n");
1908                                 scale_action = -1;
1909                         } else if (sr >= IWL_RATE_INCREASE_TH) {
1910                                 scale_action = 1;
1911                         }
1912                 }
1913         }
1914
1915         /* Sanity check; asked for decrease, but success rate or throughput
1916          * has been good at old rate.  Don't change it. */
1917         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
1918                     ((sr > IWL_RATE_HIGH_TH) ||
1919                      (current_tpt > (100 * tbl->expected_tpt[low]))))
1920                 scale_action = 0;
1921
1922         switch (scale_action) {
1923         case -1:
1924                 /* Decrease starting rate, update uCode's rate table */
1925                 if (low != IWL_RATE_INVALID) {
1926                         update_lq = 1;
1927                         index = low;
1928                 }
1929                 break;
1930         case 1:
1931                 /* Increase starting rate, update uCode's rate table */
1932                 if (high != IWL_RATE_INVALID) {
1933                         update_lq = 1;
1934                         index = high;
1935                 }
1936
1937                 break;
1938         case 0:
1939                 /* No change */
1940         default:
1941                 break;
1942         }
1943
1944         IWL_DEBUG_RATE("choose rate scale index %d action %d low %d "
1945                     "high %d type %d\n",
1946                      index, scale_action, low, high, tbl->lq_type);
1947
1948 lq_update:
1949         /* Replace uCode's rate table for the destination station. */
1950         if (update_lq) {
1951                 rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
1952                 rs_fill_link_cmd(priv, lq_sta, rate);
1953                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1954         }
1955
1956         /* Should we stay with this modulation mode, or search for a new one? */
1957         rs_stay_in_table(lq_sta);
1958
1959         /*
1960          * Search for new modulation mode if we're:
1961          * 1)  Not changing rates right now
1962          * 2)  Not just finishing up a search
1963          * 3)  Allowing a new search
1964          */
1965         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
1966                 /* Save current throughput to compare with "search" throughput*/
1967                 lq_sta->last_tpt = current_tpt;
1968
1969                 /* Select a new "search" modulation mode to try.
1970                  * If one is found, set up the new "search" table. */
1971                 if (is_legacy(tbl->lq_type))
1972                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
1973                 else if (is_siso(tbl->lq_type))
1974                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
1975                 else
1976                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
1977
1978                 /* If new "search" mode was selected, set up in uCode table */
1979                 if (lq_sta->search_better_tbl) {
1980                         /* Access the "search" table, clear its history. */
1981                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1982                         for (i = 0; i < IWL_RATE_COUNT; i++)
1983                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1984
1985                         /* Use new "search" start rate */
1986                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1987
1988                         IWL_DEBUG_RATE("Switch current  mcs: %X index: %d\n",
1989                                      tbl->current_rate, index);
1990                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
1991                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1992                 }
1993
1994                 /* If the "active" (non-search) mode was legacy,
1995                  * and we've tried switching antennas,
1996                  * but we haven't been able to try HT modes (not available),
1997                  * stay with best antenna legacy modulation for a while
1998                  * before next round of mode comparisons. */
1999                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2000                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2001                     lq_sta->action_counter >= 1) {
2002                         lq_sta->action_counter = 0;
2003                         IWL_DEBUG_RATE("LQ: STAY in legacy table\n");
2004                         rs_set_stay_in_table(priv, 1, lq_sta);
2005                 }
2006
2007                 /* If we're in an HT mode, and all 3 mode switch actions
2008                  * have been tried and compared, stay in this best modulation
2009                  * mode for a while before next round of mode comparisons. */
2010                 if (lq_sta->enable_counter &&
2011                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
2012                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2013                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2014                             (tid != MAX_TID_COUNT)) {
2015                                 IWL_DEBUG_RATE("try to aggregate tid %d\n", tid);
2016                                 rs_tl_turn_on_agg(priv, tid, lq_sta, sta);
2017                         }
2018                         lq_sta->action_counter = 0;
2019                         rs_set_stay_in_table(priv, 0, lq_sta);
2020                 }
2021
2022         /*
2023          * Else, don't search for a new modulation mode.
2024          * Put new timestamp in stay-in-modulation-mode flush timer if:
2025          * 1)  Not changing rates right now
2026          * 2)  Not just finishing up a search
2027          * 3)  flush timer is empty
2028          */
2029         } else {
2030                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
2031                         lq_sta->flush_timer = jiffies;
2032         }
2033
2034 out:
2035         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2036         i = index;
2037         lq_sta->last_txrate_idx = i;
2038
2039         return;
2040 }
2041
2042
2043 static void rs_initialize_lq(struct iwl_priv *priv,
2044                              struct ieee80211_conf *conf,
2045                              struct ieee80211_sta *sta,
2046                              struct iwl_lq_sta *lq_sta)
2047 {
2048         struct iwl_scale_tbl_info *tbl;
2049         int rate_idx;
2050         int i;
2051         u32 rate;
2052         u8 use_green = rs_use_green(priv, conf);
2053         u8 active_tbl = 0;
2054         u8 valid_tx_ant;
2055
2056         if (!sta || !lq_sta)
2057                 goto out;
2058
2059         i = lq_sta->last_txrate_idx;
2060
2061         if ((lq_sta->lq.sta_id == 0xff) &&
2062             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2063                 goto out;
2064
2065         valid_tx_ant = priv->hw_params.valid_tx_ant;
2066
2067         if (!lq_sta->search_better_tbl)
2068                 active_tbl = lq_sta->active_tbl;
2069         else
2070                 active_tbl = 1 - lq_sta->active_tbl;
2071
2072         tbl = &(lq_sta->lq_info[active_tbl]);
2073
2074         if ((i < 0) || (i >= IWL_RATE_COUNT))
2075                 i = 0;
2076
2077         rate = iwl_rates[i].plcp;
2078         tbl->ant_type = first_antenna(valid_tx_ant);
2079         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2080
2081         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2082                 rate |= RATE_MCS_CCK_MSK;
2083
2084         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2085         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2086             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2087
2088         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2089         tbl->current_rate = rate;
2090         rs_set_expected_tpt_table(lq_sta, tbl);
2091         rs_fill_link_cmd(NULL, lq_sta, rate);
2092         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2093  out:
2094         return;
2095 }
2096
2097 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2098                         struct ieee80211_tx_rate_control *txrc)
2099 {
2100
2101         struct sk_buff *skb = txrc->skb;
2102         struct ieee80211_supported_band *sband = txrc->sband;
2103         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2104         struct ieee80211_conf *conf = &priv->hw->conf;
2105         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2106         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2107         struct iwl_lq_sta *lq_sta = priv_sta;
2108         int rate_idx;
2109         u64 mask_bit = 0;
2110
2111         IWL_DEBUG_RATE_LIMIT("rate scale calculate new rate for skb\n");
2112
2113         if (sta)
2114                 mask_bit = sta->supp_rates[sband->band];
2115
2116         /* Send management frames and broadcast/multicast data using lowest
2117          * rate. */
2118         if (!ieee80211_is_data(hdr->frame_control) ||
2119             is_multicast_ether_addr(hdr->addr1) || !sta || !lq_sta) {
2120                 if (!mask_bit)
2121                         info->control.rates[0].idx =
2122                                         rate_lowest_index(sband, NULL);
2123                 else
2124                         info->control.rates[0].idx =
2125                                         rate_lowest_index(sband, sta);
2126                 return;
2127         }
2128
2129         rate_idx  = lq_sta->last_txrate_idx;
2130
2131         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2132             !lq_sta->ibss_sta_added) {
2133                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2134
2135                 if (sta_id == IWL_INVALID_STATION) {
2136                         IWL_DEBUG_RATE("LQ: ADD station %pM\n",
2137                                        hdr->addr1);
2138                         sta_id = iwl_add_station_flags(priv, hdr->addr1,
2139                                                         0, CMD_ASYNC, NULL);
2140                 }
2141                 if ((sta_id != IWL_INVALID_STATION)) {
2142                         lq_sta->lq.sta_id = sta_id;
2143                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2144                         lq_sta->ibss_sta_added = 1;
2145                         rs_initialize_lq(priv, conf, sta, lq_sta);
2146                 }
2147         }
2148
2149         if (rate_idx < 0 || rate_idx > IWL_RATE_COUNT)
2150                 rate_idx = rate_lowest_index(sband, sta);
2151         else if (sband->band == IEEE80211_BAND_5GHZ)
2152                 rate_idx -= IWL_FIRST_OFDM_RATE;
2153
2154         info->control.rates[0].idx = rate_idx;
2155 }
2156
2157 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2158                           gfp_t gfp)
2159 {
2160         struct iwl_lq_sta *lq_sta;
2161         struct iwl_priv *priv;
2162         int i, j;
2163
2164         priv = (struct iwl_priv *)priv_rate;
2165         IWL_DEBUG_RATE("create station rate scale window\n");
2166
2167         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2168
2169         if (lq_sta == NULL)
2170                 return NULL;
2171         lq_sta->lq.sta_id = 0xff;
2172
2173
2174         for (j = 0; j < LQ_SIZE; j++)
2175                 for (i = 0; i < IWL_RATE_COUNT; i++)
2176                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2177
2178         return lq_sta;
2179 }
2180
2181 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2182                          struct ieee80211_sta *sta, void *priv_sta)
2183 {
2184         int i, j;
2185         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2186         struct ieee80211_conf *conf = &priv->hw->conf;
2187         struct iwl_lq_sta *lq_sta = priv_sta;
2188         u16 mask_bit = 0;
2189
2190         lq_sta->flush_timer = 0;
2191         lq_sta->supp_rates = sta->supp_rates[sband->band];
2192         for (j = 0; j < LQ_SIZE; j++)
2193                 for (i = 0; i < IWL_RATE_COUNT; i++)
2194                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2195
2196         IWL_DEBUG_RATE("LQ: *** rate scale station global init ***\n");
2197         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2198          * the lowest or the highest rate.. Could consider using RSSI from
2199          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2200          * after assoc.. */
2201
2202         lq_sta->ibss_sta_added = 0;
2203         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2204                 u8 sta_id = iwl_find_station(priv, sta->addr);
2205
2206                 /* for IBSS the call are from tasklet */
2207                 IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2208
2209                 if (sta_id == IWL_INVALID_STATION) {
2210                         IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2211                         sta_id = iwl_add_station_flags(priv, sta->addr,
2212                                                         0, CMD_ASYNC, NULL);
2213                 }
2214                 if ((sta_id != IWL_INVALID_STATION)) {
2215                         lq_sta->lq.sta_id = sta_id;
2216                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2217                 }
2218                 /* FIXME: this is w/a remove it later */
2219                 priv->assoc_station_added = 1;
2220         }
2221
2222         lq_sta->is_dup = 0;
2223         lq_sta->is_green = rs_use_green(priv, conf);
2224         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2225         lq_sta->active_rate_basic = priv->active_rate_basic;
2226         lq_sta->band = priv->band;
2227         /*
2228          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2229          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2230          */
2231         lq_sta->active_siso_rate = sta->ht_cap.mcs.rx_mask[0] << 1;
2232         lq_sta->active_siso_rate |= sta->ht_cap.mcs.rx_mask[0] & 0x1;
2233         lq_sta->active_siso_rate &= ~((u16)0x2);
2234         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2235
2236         /* Same here */
2237         lq_sta->active_mimo2_rate = sta->ht_cap.mcs.rx_mask[1] << 1;
2238         lq_sta->active_mimo2_rate |= sta->ht_cap.mcs.rx_mask[1] & 0x1;
2239         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2240         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2241
2242         lq_sta->active_mimo3_rate = sta->ht_cap.mcs.rx_mask[2] << 1;
2243         lq_sta->active_mimo3_rate |= sta->ht_cap.mcs.rx_mask[2] & 0x1;
2244         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2245         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2246
2247         IWL_DEBUG_RATE("SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2248                      lq_sta->active_siso_rate,
2249                      lq_sta->active_mimo2_rate,
2250                      lq_sta->active_mimo3_rate);
2251
2252         /* These values will be overridden later */
2253         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2254         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2255
2256         /* as default allow aggregation for all tids */
2257         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2258         lq_sta->drv = priv;
2259
2260         /* Find highest tx rate supported by hardware and destination station */
2261         mask_bit = sta->supp_rates[sband->band] & lq_sta->active_legacy_rate;
2262         lq_sta->last_txrate_idx = 3;
2263         for (i = 0; i < sband->n_bitrates; i++)
2264                 if (mask_bit & BIT(i))
2265                         lq_sta->last_txrate_idx = i;
2266
2267         /* For MODE_IEEE80211A, skip over cck rates in global rate table */
2268         if (sband->band == IEEE80211_BAND_5GHZ)
2269                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2270
2271         rs_initialize_lq(priv, conf, sta, lq_sta);
2272 }
2273
2274 static void rs_fill_link_cmd(const struct iwl_priv *priv,
2275                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2276 {
2277         struct iwl_scale_tbl_info tbl_type;
2278         int index = 0;
2279         int rate_idx;
2280         int repeat_rate = 0;
2281         u8 ant_toggle_cnt = 0;
2282         u8 use_ht_possible = 1;
2283         u8 valid_tx_ant = 0;
2284         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2285
2286         /* Override starting rate (index 0) if needed for debug purposes */
2287         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2288
2289         /* Interpret new_rate (rate_n_flags) */
2290         memset(&tbl_type, 0, sizeof(tbl_type));
2291         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2292                                   &tbl_type, &rate_idx);
2293
2294         /* How many times should we repeat the initial rate? */
2295         if (is_legacy(tbl_type.lq_type)) {
2296                 ant_toggle_cnt = 1;
2297                 repeat_rate = IWL_NUMBER_TRY;
2298         } else {
2299                 repeat_rate = IWL_HT_NUMBER_TRY;
2300         }
2301
2302         lq_cmd->general_params.mimo_delimiter =
2303                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2304
2305         /* Fill 1st table entry (index 0) */
2306         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2307
2308         if (num_of_ant(tbl_type.ant_type) == 1) {
2309                 lq_cmd->general_params.single_stream_ant_msk =
2310                                                 tbl_type.ant_type;
2311         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2312                 lq_cmd->general_params.dual_stream_ant_msk =
2313                                                 tbl_type.ant_type;
2314         } /* otherwise we don't modify the existing value */
2315
2316         index++;
2317         repeat_rate--;
2318
2319         if (priv)
2320                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2321
2322         /* Fill rest of rate table */
2323         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2324                 /* Repeat initial/next rate.
2325                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2326                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2327                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2328                         if (is_legacy(tbl_type.lq_type)) {
2329                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2330                                         ant_toggle_cnt++;
2331                                 else if (priv &&
2332                                          rs_toggle_antenna(valid_tx_ant,
2333                                                         &new_rate, &tbl_type))
2334                                         ant_toggle_cnt = 1;
2335 }
2336
2337                         /* Override next rate if needed for debug purposes */
2338                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2339
2340                         /* Fill next table entry */
2341                         lq_cmd->rs_table[index].rate_n_flags =
2342                                         cpu_to_le32(new_rate);
2343                         repeat_rate--;
2344                         index++;
2345                 }
2346
2347                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2348                                                 &rate_idx);
2349
2350                 /* Indicate to uCode which entries might be MIMO.
2351                  * If initial rate was MIMO, this will finally end up
2352                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2353                 if (is_mimo(tbl_type.lq_type))
2354                         lq_cmd->general_params.mimo_delimiter = index;
2355
2356                 /* Get next rate */
2357                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2358                                              use_ht_possible);
2359
2360                 /* How many times should we repeat the next rate? */
2361                 if (is_legacy(tbl_type.lq_type)) {
2362                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2363                                 ant_toggle_cnt++;
2364                         else if (priv &&
2365                                  rs_toggle_antenna(valid_tx_ant,
2366                                                    &new_rate, &tbl_type))
2367                                 ant_toggle_cnt = 1;
2368
2369                         repeat_rate = IWL_NUMBER_TRY;
2370                 } else {
2371                         repeat_rate = IWL_HT_NUMBER_TRY;
2372                 }
2373
2374                 /* Don't allow HT rates after next pass.
2375                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2376                 use_ht_possible = 0;
2377
2378                 /* Override next rate if needed for debug purposes */
2379                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2380
2381                 /* Fill next table entry */
2382                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2383
2384                 index++;
2385                 repeat_rate--;
2386         }
2387
2388         lq_cmd->agg_params.agg_frame_cnt_limit = 64;
2389         lq_cmd->agg_params.agg_dis_start_th = 3;
2390         lq_cmd->agg_params.agg_time_limit = cpu_to_le16(4000);
2391 }
2392
2393 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2394 {
2395         return hw->priv;
2396 }
2397 /* rate scale requires free function to be implemented */
2398 static void rs_free(void *priv_rate)
2399 {
2400         return;
2401 }
2402
2403 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2404                         void *priv_sta)
2405 {
2406         struct iwl_lq_sta *lq_sta = priv_sta;
2407         struct iwl_priv *priv __maybe_unused = priv_r;
2408
2409         IWL_DEBUG_RATE("enter\n");
2410         kfree(lq_sta);
2411         IWL_DEBUG_RATE("leave\n");
2412 }
2413
2414
2415 #ifdef CONFIG_MAC80211_DEBUGFS
2416 static int open_file_generic(struct inode *inode, struct file *file)
2417 {
2418         file->private_data = inode->i_private;
2419         return 0;
2420 }
2421 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2422                              u32 *rate_n_flags, int index)
2423 {
2424         struct iwl_priv *priv;
2425
2426         priv = lq_sta->drv;
2427         if (lq_sta->dbg_fixed_rate) {
2428                 if (index < 12) {
2429                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2430                 } else {
2431                         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2432                                 *rate_n_flags = 0x800D;
2433                         else
2434                                 *rate_n_flags = 0x820A;
2435                 }
2436                 IWL_DEBUG_RATE("Fixed rate ON\n");
2437         } else {
2438                 IWL_DEBUG_RATE("Fixed rate OFF\n");
2439         }
2440 }
2441
2442 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2443                         const char __user *user_buf, size_t count, loff_t *ppos)
2444 {
2445         struct iwl_lq_sta *lq_sta = file->private_data;
2446         struct iwl_priv *priv;
2447         char buf[64];
2448         int buf_size;
2449         u32 parsed_rate;
2450
2451         priv = lq_sta->drv;
2452         memset(buf, 0, sizeof(buf));
2453         buf_size = min(count, sizeof(buf) -  1);
2454         if (copy_from_user(buf, user_buf, buf_size))
2455                 return -EFAULT;
2456
2457         if (sscanf(buf, "%x", &parsed_rate) == 1)
2458                 lq_sta->dbg_fixed_rate = parsed_rate;
2459         else
2460                 lq_sta->dbg_fixed_rate = 0;
2461
2462         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2463         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2464         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2465         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2466
2467         IWL_DEBUG_RATE("sta_id %d rate 0x%X\n",
2468                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2469
2470         if (lq_sta->dbg_fixed_rate) {
2471                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2472                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2473         }
2474
2475         return count;
2476 }
2477
2478 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2479                         char __user *user_buf, size_t count, loff_t *ppos)
2480 {
2481         char buff[1024];
2482         int desc = 0;
2483         int i = 0;
2484
2485         struct iwl_lq_sta *lq_sta = file->private_data;
2486
2487         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2488         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2489                         lq_sta->total_failed, lq_sta->total_success,
2490                         lq_sta->active_legacy_rate);
2491         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2492                         lq_sta->dbg_fixed_rate);
2493         desc += sprintf(buff+desc, "general:"
2494                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2495                 lq_sta->lq.general_params.flags,
2496                 lq_sta->lq.general_params.mimo_delimiter,
2497                 lq_sta->lq.general_params.single_stream_ant_msk,
2498                 lq_sta->lq.general_params.dual_stream_ant_msk);
2499
2500         desc += sprintf(buff+desc, "agg:"
2501                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2502                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2503                         lq_sta->lq.agg_params.agg_dis_start_th,
2504                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2505
2506         desc += sprintf(buff+desc,
2507                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2508                         lq_sta->lq.general_params.start_rate_index[0],
2509                         lq_sta->lq.general_params.start_rate_index[1],
2510                         lq_sta->lq.general_params.start_rate_index[2],
2511                         lq_sta->lq.general_params.start_rate_index[3]);
2512
2513
2514         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2515                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2516                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2517
2518         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2519 }
2520
2521 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2522         .write = rs_sta_dbgfs_scale_table_write,
2523         .read = rs_sta_dbgfs_scale_table_read,
2524         .open = open_file_generic,
2525 };
2526 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2527                         char __user *user_buf, size_t count, loff_t *ppos)
2528 {
2529         char buff[1024];
2530         int desc = 0;
2531         int i, j;
2532
2533         struct iwl_lq_sta *lq_sta = file->private_data;
2534         for (i = 0; i < LQ_SIZE; i++) {
2535                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2536                                 "rate=0x%X\n",
2537                                 lq_sta->active_tbl == i ? "*" : "x",
2538                                 lq_sta->lq_info[i].lq_type,
2539                                 lq_sta->lq_info[i].is_SGI,
2540                                 lq_sta->lq_info[i].is_fat,
2541                                 lq_sta->lq_info[i].is_dup,
2542                                 lq_sta->lq_info[i].current_rate);
2543                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2544                         desc += sprintf(buff+desc,
2545                                 "counter=%d success=%d %%=%d\n",
2546                                 lq_sta->lq_info[i].win[j].counter,
2547                                 lq_sta->lq_info[i].win[j].success_counter,
2548                                 lq_sta->lq_info[i].win[j].success_ratio);
2549                 }
2550         }
2551         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2552 }
2553
2554 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2555         .read = rs_sta_dbgfs_stats_table_read,
2556         .open = open_file_generic,
2557 };
2558
2559 static void rs_add_debugfs(void *priv, void *priv_sta,
2560                                         struct dentry *dir)
2561 {
2562         struct iwl_lq_sta *lq_sta = priv_sta;
2563         lq_sta->rs_sta_dbgfs_scale_table_file =
2564                 debugfs_create_file("rate_scale_table", 0600, dir,
2565                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2566         lq_sta->rs_sta_dbgfs_stats_table_file =
2567                 debugfs_create_file("rate_stats_table", 0600, dir,
2568                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2569         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2570                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2571                 &lq_sta->tx_agg_tid_en);
2572
2573 }
2574
2575 static void rs_remove_debugfs(void *priv, void *priv_sta)
2576 {
2577         struct iwl_lq_sta *lq_sta = priv_sta;
2578         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2579         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2580         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2581 }
2582 #endif
2583
2584 static struct rate_control_ops rs_ops = {
2585         .module = NULL,
2586         .name = RS_NAME,
2587         .tx_status = rs_tx_status,
2588         .get_rate = rs_get_rate,
2589         .rate_init = rs_rate_init,
2590         .alloc = rs_alloc,
2591         .free = rs_free,
2592         .alloc_sta = rs_alloc_sta,
2593         .free_sta = rs_free_sta,
2594 #ifdef CONFIG_MAC80211_DEBUGFS
2595         .add_sta_debugfs = rs_add_debugfs,
2596         .remove_sta_debugfs = rs_remove_debugfs,
2597 #endif
2598 };
2599
2600 int iwlagn_rate_control_register(void)
2601 {
2602         return ieee80211_rate_control_register(&rs_ops);
2603 }
2604
2605 void iwlagn_rate_control_unregister(void)
2606 {
2607         ieee80211_rate_control_unregister(&rs_ops);
2608 }
2609