drivers/net/wireless/iwlwifi/iwl-agn-rs.c

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