git.oblomov.eu Git - linux-2.6/blob - drivers/net/wireless/iwlwifi/iwl-agn-rs.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2005 - 2009 Intel Corporation. All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  * Contact Information:
  22  *  Intel Linux Wireless <ilw@linux.intel.com>
  23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  24  *
  25  *****************************************************************************/
  26 #include <linux/kernel.h>
  27 #include <linux/init.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/wireless.h>
  30 #include <net/mac80211.h>
  31
  32 #include <linux/netdevice.h>
  33 #include <linux/etherdevice.h>
  34 #include <linux/delay.h>
  35
  36 #include <linux/workqueue.h>
  37
  38 #include "iwl-dev.h"
  39 #include "iwl-sta.h"
  40 #include "iwl-core.h"
  41
  42 #define RS_NAME "iwl-agn-rs"
  43
  44 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
  45 #define IWL_NUMBER_TRY      1
  46 #define IWL_HT_NUMBER_TRY   3
  47
  48 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
  49 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
  50 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
  51
  52 /* max allowed rate miss before sync LQ cmd */
  53 #define IWL_MISSED_RATE_MAX             15
  54 /* max time to accum history 2 seconds */
  55 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
  56
  57 static u8 rs_ht_to_legacy[] = {
  58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  60         IWL_RATE_6M_INDEX,
  61         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
  62         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
  63         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
  64         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
  65 };
  66
  67 static const u8 ant_toggle_lookup[] = {
  68         /*ANT_NONE -> */ ANT_NONE,
  69         /*ANT_A    -> */ ANT_B,
  70         /*ANT_B    -> */ ANT_C,
  71         /*ANT_AB   -> */ ANT_BC,
  72         /*ANT_C    -> */ ANT_A,
  73         /*ANT_AC   -> */ ANT_AB,
  74         /*ANT_BC   -> */ ANT_AC,
  75         /*ANT_ABC  -> */ ANT_ABC,
  76 };
  77
  78 /**
  79  * struct iwl_rate_scale_data -- tx success history for one rate
  80  */
  81 struct iwl_rate_scale_data {
  82         u64 data;               /* bitmap of successful frames */
  83         s32 success_counter;    /* number of frames successful */
  84         s32 success_ratio;      /* per-cent * 128  */
  85         s32 counter;            /* number of frames attempted */
  86         s32 average_tpt;        /* success ratio * expected throughput */
  87         unsigned long stamp;
  88 };
  89
  90 /**
  91  * struct iwl_scale_tbl_info -- tx params and success history for all rates
  92  *
  93  * There are two of these in struct iwl_lq_sta,
  94  * one for "active", and one for "search".
  95  */
  96 struct iwl_scale_tbl_info {
  97         enum iwl_table_type lq_type;
  98         u8 ant_type;
  99         u8 is_SGI;      /* 1 = short guard interval */
 100         u8 is_fat;      /* 1 = 40 MHz channel width */
 101         u8 is_dup;      /* 1 = duplicated data streams */
 102         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
 103         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
 104         u32 current_rate;  /* rate_n_flags, uCode API format */
 105         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
 106 };
 107
 108 struct iwl_traffic_load {
 109         unsigned long time_stamp;       /* age of the oldest statistics */
 110         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
 111                                                  * slice */
 112         u32 total;                      /* total num of packets during the
 113                                          * last TID_MAX_TIME_DIFF */
 114         u8 queue_count;                 /* number of queues that has
 115                                          * been used since the last cleanup */
 116         u8 head;                        /* start of the circular buffer */
 117 };
 118
 119 /**
 120  * struct iwl_lq_sta -- driver's rate scaling private structure
 121  *
 122  * Pointer to this gets passed back and forth between driver and mac80211.
 123  */
 124 struct iwl_lq_sta {
 125         u8 active_tbl;          /* index of active table, range 0-1 */
 126         u8 enable_counter;      /* indicates HT mode */
 127         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
 128         u8 search_better_tbl;   /* 1: currently trying alternate mode */
 129         s32 last_tpt;
 130
 131         /* The following determine when to search for a new mode */
 132         u32 table_count_limit;
 133         u32 max_failure_limit;  /* # failed frames before new search */
 134         u32 max_success_limit;  /* # successful frames before new search */
 135         u32 table_count;
 136         u32 total_failed;       /* total failed frames, any/all rates */
 137         u32 total_success;      /* total successful frames, any/all rates */
 138         u32 flush_timer;        /* time staying in mode before new search */
 139
 140         u8 action_counter;      /* # mode-switch actions tried */
 141         u8 is_green;
 142         u8 is_dup;
 143         enum ieee80211_band band;
 144         u8 ibss_sta_added;
 145
 146         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
 147         u32 supp_rates;
 148         u16 active_legacy_rate;
 149         u16 active_siso_rate;
 150         u16 active_mimo2_rate;
 151         u16 active_mimo3_rate;
 152         u16 active_rate_basic;
 153         s8 max_rate_idx;     /* Max rate set by user */
 154         u8 missed_rate_counter;
 155
 156         struct iwl_link_quality_cmd lq;
 157         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
 158         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
 159         u8 tx_agg_tid_en;
 160 #ifdef CONFIG_MAC80211_DEBUGFS
 161         struct dentry *rs_sta_dbgfs_scale_table_file;
 162         struct dentry *rs_sta_dbgfs_stats_table_file;
 163         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
 164         u32 dbg_fixed_rate;
 165 #endif
 166         struct iwl_priv *drv;
 167
 168         /* used to be in sta_info */
 169         int last_txrate_idx;
 170 };
 171
 172 static void rs_rate_scale_perform(struct iwl_priv *priv,
 173                                    struct ieee80211_hdr *hdr,
 174                                    struct ieee80211_sta *sta,
 175                                    struct iwl_lq_sta *lq_sta);
 176 static void rs_fill_link_cmd(const struct iwl_priv *priv,
 177                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
 178
 179
 180 #ifdef CONFIG_MAC80211_DEBUGFS
 181 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 182                              u32 *rate_n_flags, int index);
 183 #else
 184 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 185                              u32 *rate_n_flags, int index)
 186 {}
 187 #endif
 188
 189 /*
 190  * Expected throughput metrics for following rates:
 191  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
 192  * "G" is the only table that supports CCK (the first 4 rates).
 193  */
 194 /*FIXME:RS:need to separate tables for MIMO2/MIMO3*/
 195 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
 196         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
 197 };
 198
 199 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
 200         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
 201 };
 202
 203 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
 204         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
 205 };
 206
 207 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
 208         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
 209 };
 210
 211 static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
 212         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
 213 };
 214
 215 static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
 216         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
 217 };
 218
 219 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
 220         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
 221 };
 222
 223 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
 224         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
 225 };
 226
 227 static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
 228         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
 229 };
 230
 231 static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
 232         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
 233 };
 234
 235 static inline u8 rs_extract_rate(u32 rate_n_flags)
 236 {
 237         return (u8)(rate_n_flags & 0xFF);
 238 }
 239
 240 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
 241 {
 242         window->data = 0;
 243         window->success_counter = 0;
 244         window->success_ratio = IWL_INVALID_VALUE;
 245         window->counter = 0;
 246         window->average_tpt = IWL_INVALID_VALUE;
 247         window->stamp = 0;
 248 }
 249
 250 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
 251 {
 252         return (ant_type & valid_antenna) == ant_type;
 253 }
 254
 255 /*
 256  *      removes the old data from the statistics. All data that is older than
 257  *      TID_MAX_TIME_DIFF, will be deleted.
 258  */
 259 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
 260 {
 261         /* The oldest age we want to keep */
 262         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
 263
 264         while (tl->queue_count &&
 265                (tl->time_stamp < oldest_time)) {
 266                 tl->total -= tl->packet_count[tl->head];
 267                 tl->packet_count[tl->head] = 0;
 268                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
 269                 tl->queue_count--;
 270                 tl->head++;
 271                 if (tl->head >= TID_QUEUE_MAX_SIZE)
 272                         tl->head = 0;
 273         }
 274 }
 275
 276 /*
 277  *      increment traffic load value for tid and also remove
 278  *      any old values if passed the certain time period
 279  */
 280 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
 281                            struct ieee80211_hdr *hdr)
 282 {
 283         u32 curr_time = jiffies_to_msecs(jiffies);
 284         u32 time_diff;
 285         s32 index;
 286         struct iwl_traffic_load *tl = NULL;
 287         u8 tid;
 288
 289         if (ieee80211_is_data_qos(hdr->frame_control)) {
 290                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 291                 tid = qc[0] & 0xf;
 292         } else
 293                 return MAX_TID_COUNT;
 294
 295         tl = &lq_data->load[tid];
 296
 297         curr_time -= curr_time % TID_ROUND_VALUE;
 298
 299         /* Happens only for the first packet. Initialize the data */
 300         if (!(tl->queue_count)) {
 301                 tl->total = 1;
 302                 tl->time_stamp = curr_time;
 303                 tl->queue_count = 1;
 304                 tl->head = 0;
 305                 tl->packet_count[0] = 1;
 306                 return MAX_TID_COUNT;
 307         }
 308
 309         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 310         index = time_diff / TID_QUEUE_CELL_SPACING;
 311
 312         /* The history is too long: remove data that is older than */
 313         /* TID_MAX_TIME_DIFF */
 314         if (index >= TID_QUEUE_MAX_SIZE)
 315                 rs_tl_rm_old_stats(tl, curr_time);
 316
 317         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
 318         tl->packet_count[index] = tl->packet_count[index] + 1;
 319         tl->total = tl->total + 1;
 320
 321         if ((index + 1) > tl->queue_count)
 322                 tl->queue_count = index + 1;
 323
 324         return tid;
 325 }
 326
 327 /*
 328         get the traffic load value for tid
 329 */
 330 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
 331 {
 332         u32 curr_time = jiffies_to_msecs(jiffies);
 333         u32 time_diff;
 334         s32 index;
 335         struct iwl_traffic_load *tl = NULL;
 336
 337         if (tid >= TID_MAX_LOAD_COUNT)
 338                 return 0;
 339
 340         tl = &(lq_data->load[tid]);
 341
 342         curr_time -= curr_time % TID_ROUND_VALUE;
 343
 344         if (!(tl->queue_count))
 345                 return 0;
 346
 347         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 348         index = time_diff / TID_QUEUE_CELL_SPACING;
 349
 350         /* The history is too long: remove data that is older than */
 351         /* TID_MAX_TIME_DIFF */
 352         if (index >= TID_QUEUE_MAX_SIZE)
 353                 rs_tl_rm_old_stats(tl, curr_time);
 354
 355         return tl->total;
 356 }
 357
 358 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
 359                                       struct iwl_lq_sta *lq_data, u8 tid,
 360                                       struct ieee80211_sta *sta)
 361 {
 362         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
 363                 IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n",
 364                                 sta->addr, tid);
 365                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
 366         }
 367 }
 368
 369 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
 370                               struct iwl_lq_sta *lq_data,
 371                               struct ieee80211_sta *sta)
 372 {
 373         if ((tid < TID_MAX_LOAD_COUNT))
 374                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 375         else if (tid == IWL_AGG_ALL_TID)
 376                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
 377                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 378 }
 379
 380 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
 381 {
 382         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
 383                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
 384                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
 385 }
 386
 387 /**
 388  * rs_collect_tx_data - Update the success/failure sliding window
 389  *
 390  * We keep a sliding window of the last 62 packets transmitted
 391  * at this rate.  window->data contains the bitmask of successful
 392  * packets.
 393  */
 394 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
 395                               int scale_index, s32 tpt, int retries,
 396                               int successes)
 397 {
 398         struct iwl_rate_scale_data *window = NULL;
 399         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 400         s32 fail_count;
 401
 402         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 403                 return -EINVAL;
 404
 405         /* Select data for current tx bit rate */
 406         window = &(windows[scale_index]);
 407
 408         /*
 409          * Keep track of only the latest 62 tx frame attempts in this rate's
 410          * history window; anything older isn't really relevant any more.
 411          * If we have filled up the sliding window, drop the oldest attempt;
 412          * if the oldest attempt (highest bit in bitmap) shows "success",
 413          * subtract "1" from the success counter (this is the main reason
 414          * we keep these bitmaps!).
 415          */
 416         while (retries > 0) {
 417                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 418
 419                         /* remove earliest */
 420                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 421
 422                         if (window->data & mask) {
 423                                 window->data &= ~mask;
 424                                 window->success_counter--;
 425                         }
 426                 }
 427
 428                 /* Increment frames-attempted counter */
 429                 window->counter++;
 430
 431                 /* Shift bitmap by one frame (throw away oldest history),
 432                  * OR in "1", and increment "success" if this
 433                  * frame was successful. */
 434                 window->data <<= 1;
 435                 if (successes > 0) {
 436                         window->success_counter++;
 437                         window->data |= 0x1;
 438                         successes--;
 439                 }
 440
 441                 retries--;
 442         }
 443
 444         /* Calculate current success ratio, avoid divide-by-0! */
 445         if (window->counter > 0)
 446                 window->success_ratio = 128 * (100 * window->success_counter)
 447                                         / window->counter;
 448         else
 449                 window->success_ratio = IWL_INVALID_VALUE;
 450
 451         fail_count = window->counter - window->success_counter;
 452
 453         /* Calculate average throughput, if we have enough history. */
 454         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 455             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 456                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 457         else
 458                 window->average_tpt = IWL_INVALID_VALUE;
 459
 460         /* Tag this window as having been updated */
 461         window->stamp = jiffies;
 462
 463         return 0;
 464 }
 465
 466 /*
 467  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 468  */
 469 /* FIXME:RS:remove this function and put the flags statically in the table */
 470 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 471                                  struct iwl_scale_tbl_info *tbl,
 472                                  int index, u8 use_green)
 473 {
 474         u32 rate_n_flags = 0;
 475
 476         if (is_legacy(tbl->lq_type)) {
 477                 rate_n_flags = iwl_rates[index].plcp;
 478                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 479                         rate_n_flags |= RATE_MCS_CCK_MSK;
 480
 481         } else if (is_Ht(tbl->lq_type)) {
 482                 if (index > IWL_LAST_OFDM_RATE) {
 483                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 484                         index = IWL_LAST_OFDM_RATE;
 485                 }
 486                 rate_n_flags = RATE_MCS_HT_MSK;
 487
 488                 if (is_siso(tbl->lq_type))
 489                         rate_n_flags |= iwl_rates[index].plcp_siso;
 490                 else if (is_mimo2(tbl->lq_type))
 491                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 492                 else
 493                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 494         } else {
 495                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 496         }
 497
 498         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 499                                                      RATE_MCS_ANT_ABC_MSK);
 500
 501         if (is_Ht(tbl->lq_type)) {
 502                 if (tbl->is_fat) {
 503                         if (tbl->is_dup)
 504                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 505                         else
 506                                 rate_n_flags |= RATE_MCS_FAT_MSK;
 507                 }
 508                 if (tbl->is_SGI)
 509                         rate_n_flags |= RATE_MCS_SGI_MSK;
 510
 511                 if (use_green) {
 512                         rate_n_flags |= RATE_MCS_GF_MSK;
 513                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 514                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 515                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 516                         }
 517                 }
 518         }
 519         return rate_n_flags;
 520 }
 521
 522 /*
 523  * Interpret uCode API's rate_n_flags format,
 524  * fill "search" or "active" tx mode table.
 525  */
 526 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 527                                     enum ieee80211_band band,
 528                                     struct iwl_scale_tbl_info *tbl,
 529                                     int *rate_idx)
 530 {
 531         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 532         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 533         u8 mcs;
 534
 535         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 536
 537         if (*rate_idx  == IWL_RATE_INVALID) {
 538                 *rate_idx = -1;
 539                 return -EINVAL;
 540         }
 541         tbl->is_SGI = 0;        /* default legacy setup */
 542         tbl->is_fat = 0;
 543         tbl->is_dup = 0;
 544         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 545         tbl->lq_type = LQ_NONE;
 546
 547         /* legacy rate format */
 548         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 549                 if (num_of_ant == 1) {
 550                         if (band == IEEE80211_BAND_5GHZ)
 551                                 tbl->lq_type = LQ_A;
 552                         else
 553                                 tbl->lq_type = LQ_G;
 554                 }
 555         /* HT rate format */
 556         } else {
 557                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 558                         tbl->is_SGI = 1;
 559
 560                 if ((rate_n_flags & RATE_MCS_FAT_MSK) ||
 561                     (rate_n_flags & RATE_MCS_DUP_MSK))
 562                         tbl->is_fat = 1;
 563
 564                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 565                         tbl->is_dup = 1;
 566
 567                 mcs = rs_extract_rate(rate_n_flags);
 568
 569                 /* SISO */
 570                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 571                         if (num_of_ant == 1)
 572                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 573                 /* MIMO2 */
 574                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 575                         if (num_of_ant == 2)
 576                                 tbl->lq_type = LQ_MIMO2;
 577                 /* MIMO3 */
 578                 } else {
 579                         if (num_of_ant == 3)
 580                                 tbl->lq_type = LQ_MIMO3;
 581                 }
 582         }
 583         return 0;
 584 }
 585
 586 /* switch to another antenna/antennas and return 1 */
 587 /* if no other valid antenna found, return 0 */
 588 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 589                              struct iwl_scale_tbl_info *tbl)
 590 {
 591         u8 new_ant_type;
 592
 593         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 594                 return 0;
 595
 596         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 597                 return 0;
 598
 599         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 600
 601         while ((new_ant_type != tbl->ant_type) &&
 602                !rs_is_valid_ant(valid_ant, new_ant_type))
 603                 new_ant_type = ant_toggle_lookup[new_ant_type];
 604
 605         if (new_ant_type == tbl->ant_type)
 606                 return 0;
 607
 608         tbl->ant_type = new_ant_type;
 609         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 610         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 611         return 1;
 612 }
 613
 614 /* FIXME:RS: in 4965 we don't use greenfield at all */
 615 /* FIXME:RS: don't use greenfield for now in TX */
 616 #if 0
 617 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
 618 {
 619         return (conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
 620                 priv->current_ht_config.is_green_field &&
 621                 !priv->current_ht_config.non_GF_STA_present;
 622 }
 623 #endif
 624 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
 625 {
 626         return 0;
 627 }
 628
 629 /**
 630  * rs_get_supported_rates - get the available rates
 631  *
 632  * if management frame or broadcast frame only return
 633  * basic available rates.
 634  *
 635  */
 636 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 637                                   struct ieee80211_hdr *hdr,
 638                                   enum iwl_table_type rate_type)
 639 {
 640         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 641             lq_sta->active_rate_basic)
 642                 return lq_sta->active_rate_basic;
 643
 644         if (is_legacy(rate_type)) {
 645                 return lq_sta->active_legacy_rate;
 646         } else {
 647                 if (is_siso(rate_type))
 648                         return lq_sta->active_siso_rate;
 649                 else if (is_mimo2(rate_type))
 650                         return lq_sta->active_mimo2_rate;
 651                 else
 652                         return lq_sta->active_mimo3_rate;
 653         }
 654 }
 655
 656 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 657                                 int rate_type)
 658 {
 659         u8 high = IWL_RATE_INVALID;
 660         u8 low = IWL_RATE_INVALID;
 661
 662         /* 802.11A or ht walks to the next literal adjacent rate in
 663          * the rate table */
 664         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 665                 int i;
 666                 u32 mask;
 667
 668                 /* Find the previous rate that is in the rate mask */
 669                 i = index - 1;
 670                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 671                         if (rate_mask & mask) {
 672                                 low = i;
 673                                 break;
 674                         }
 675                 }
 676
 677                 /* Find the next rate that is in the rate mask */
 678                 i = index + 1;
 679                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 680                         if (rate_mask & mask) {
 681                                 high = i;
 682                                 break;
 683                         }
 684                 }
 685
 686                 return (high << 8) | low;
 687         }
 688
 689         low = index;
 690         while (low != IWL_RATE_INVALID) {
 691                 low = iwl_rates[low].prev_rs;
 692                 if (low == IWL_RATE_INVALID)
 693                         break;
 694                 if (rate_mask & (1 << low))
 695                         break;
 696                 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
 697         }
 698
 699         high = index;
 700         while (high != IWL_RATE_INVALID) {
 701                 high = iwl_rates[high].next_rs;
 702                 if (high == IWL_RATE_INVALID)
 703                         break;
 704                 if (rate_mask & (1 << high))
 705                         break;
 706                 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
 707         }
 708
 709         return (high << 8) | low;
 710 }
 711
 712 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 713                              struct iwl_scale_tbl_info *tbl,
 714                              u8 scale_index, u8 ht_possible)
 715 {
 716         s32 low;
 717         u16 rate_mask;
 718         u16 high_low;
 719         u8 switch_to_legacy = 0;
 720         u8 is_green = lq_sta->is_green;
 721
 722         /* check if we need to switch from HT to legacy rates.
 723          * assumption is that mandatory rates (1Mbps or 6Mbps)
 724          * are always supported (spec demand) */
 725         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 726                 switch_to_legacy = 1;
 727                 scale_index = rs_ht_to_legacy[scale_index];
 728                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 729                         tbl->lq_type = LQ_A;
 730                 else
 731                         tbl->lq_type = LQ_G;
 732
 733                 if (num_of_ant(tbl->ant_type) > 1)
 734                         tbl->ant_type = ANT_A;/*FIXME:RS*/
 735
 736                 tbl->is_fat = 0;
 737                 tbl->is_SGI = 0;
 738         }
 739
 740         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 741
 742         /* Mask with station rate restriction */
 743         if (is_legacy(tbl->lq_type)) {
 744                 /* supp_rates has no CCK bits in A mode */
 745                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 746                         rate_mask  = (u16)(rate_mask &
 747                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 748                 else
 749                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 750         }
 751
 752         /* If we switched from HT to legacy, check current rate */
 753         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 754                 low = scale_index;
 755                 goto out;
 756         }
 757
 758         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 759                                         tbl->lq_type);
 760         low = high_low & 0xff;
 761
 762         if (low == IWL_RATE_INVALID)
 763                 low = scale_index;
 764
 765 out:
 766         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 767 }
 768
 769 /*
 770  * mac80211 sends us Tx status
 771  */
 772 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 773                          struct ieee80211_sta *sta, void *priv_sta,
 774                          struct sk_buff *skb)
 775 {
 776         int status;
 777         u8 retries;
 778         int rs_index, index = 0;
 779         struct iwl_lq_sta *lq_sta = priv_sta;
 780         struct iwl_link_quality_cmd *table;
 781         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 782         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 783         struct ieee80211_hw *hw = priv->hw;
 784         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 785         struct iwl_rate_scale_data *window = NULL;
 786         struct iwl_rate_scale_data *search_win = NULL;
 787         u32 tx_rate;
 788         struct iwl_scale_tbl_info tbl_type;
 789         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
 790         u8 active_index = 0;
 791         s32 tpt = 0;
 792
 793         IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 794
 795         if (!ieee80211_is_data(hdr->frame_control) ||
 796             is_multicast_ether_addr(hdr->addr1))
 797                 return;
 798
 799         /* This packet was aggregated but doesn't carry rate scale info */
 800         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 801             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 802                 return;
 803
 804         if (info->flags & IEEE80211_TX_STAT_AMPDU)
 805                 retries = 0;
 806         else
 807                 retries = info->status.rates[0].count - 1;
 808
 809         if (retries > 15)
 810                 retries = 15;
 811
 812         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 813             !lq_sta->ibss_sta_added)
 814                 goto out;
 815
 816         table = &lq_sta->lq;
 817         active_index = lq_sta->active_tbl;
 818
 819         curr_tbl = &(lq_sta->lq_info[active_index]);
 820         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
 821         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 822         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
 823
 824         /*
 825          * Ignore this Tx frame response if its initial rate doesn't match
 826          * that of latest Link Quality command.  There may be stragglers
 827          * from a previous Link Quality command, but we're no longer interested
 828          * in those; they're either from the "active" mode while we're trying
 829          * to check "search" mode, or a prior "search" mode after we've moved
 830          * to a new "search" mode (which might become the new "active" mode).
 831          */
 832         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 833         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 834         if (priv->band == IEEE80211_BAND_5GHZ)
 835                 rs_index -= IWL_FIRST_OFDM_RATE;
 836
 837         if ((info->status.rates[0].idx < 0) ||
 838             (tbl_type.is_SGI != !!(info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)) ||
 839             (tbl_type.is_fat != !!(info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 840             (tbl_type.is_dup != !!(info->status.rates[0].flags & IEEE80211_TX_RC_DUP_DATA)) ||
 841             (tbl_type.ant_type != info->antenna_sel_tx) ||
 842             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) ||
 843             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 844             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
 845              hw->wiphy->bands[info->band]->bitrates[info->status.rates[0].idx].bitrate)) {
 846                 IWL_DEBUG_RATE(priv, "initial rate does not match 0x%x\n", tx_rate);
 847                 /* the last LQ command could failed so the LQ in ucode not
 848                  * the same in driver sync up
 849                  */
 850                 lq_sta->missed_rate_counter++;
 851                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 852                         lq_sta->missed_rate_counter = 0;
 853                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 854                 }
 855                 goto out;
 856         }
 857
 858         lq_sta->missed_rate_counter = 0;
 859         /* Update frame history window with "failure" for each Tx retry. */
 860         while (retries) {
 861                 /* Look up the rate and other info used for each tx attempt.
 862                  * Each tx attempt steps one entry deeper in the rate table. */
 863                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 864                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 865                                           &tbl_type, &rs_index);
 866
 867                 /* If type matches "search" table,
 868                  * add failure to "search" history */
 869                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
 870                     (tbl_type.ant_type == search_tbl->ant_type) &&
 871                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
 872                         if (search_tbl->expected_tpt)
 873                                 tpt = search_tbl->expected_tpt[rs_index];
 874                         else
 875                                 tpt = 0;
 876                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
 877
 878                 /* Else if type matches "current/active" table,
 879                  * add failure to "current/active" history */
 880                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 881                            (tbl_type.ant_type == curr_tbl->ant_type) &&
 882                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 883                         if (curr_tbl->expected_tpt)
 884                                 tpt = curr_tbl->expected_tpt[rs_index];
 885                         else
 886                                 tpt = 0;
 887                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
 888                 }
 889
 890                 /* If not searching for a new mode, increment failed counter
 891                  * ... this helps determine when to start searching again */
 892                 if (lq_sta->stay_in_tbl)
 893                         lq_sta->total_failed++;
 894                 --retries;
 895                 index++;
 896
 897         }
 898
 899         /*
 900          * Find (by rate) the history window to update with final Tx attempt;
 901          * if Tx was successful first try, use original rate,
 902          * else look up the rate that was, finally, successful.
 903          */
 904         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 905         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 906
 907         /* Update frame history window with "success" if Tx got ACKed ... */
 908         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
 909
 910         /* If type matches "search" table,
 911          * add final tx status to "search" history */
 912         if ((tbl_type.lq_type == search_tbl->lq_type) &&
 913             (tbl_type.ant_type == search_tbl->ant_type) &&
 914             (tbl_type.is_SGI == search_tbl->is_SGI)) {
 915                 if (search_tbl->expected_tpt)
 916                         tpt = search_tbl->expected_tpt[rs_index];
 917                 else
 918                         tpt = 0;
 919                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 920                         rs_collect_tx_data(search_win, rs_index, tpt,
 921                                            info->status.ampdu_ack_len,
 922                                            info->status.ampdu_ack_map);
 923                 else
 924                         rs_collect_tx_data(search_win, rs_index, tpt,
 925                                            1, status);
 926         /* Else if type matches "current/active" table,
 927          * add final tx status to "current/active" history */
 928         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 929                    (tbl_type.ant_type == curr_tbl->ant_type) &&
 930                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 931                 if (curr_tbl->expected_tpt)
 932                         tpt = curr_tbl->expected_tpt[rs_index];
 933                 else
 934                         tpt = 0;
 935                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 936                         rs_collect_tx_data(window, rs_index, tpt,
 937                                            info->status.ampdu_ack_len,
 938                                            info->status.ampdu_ack_map);
 939                 else
 940                         rs_collect_tx_data(window, rs_index, tpt,
 941                                            1, status);
 942         }
 943
 944         /* If not searching for new mode, increment success/failed counter
 945          * ... these help determine when to start searching again */
 946         if (lq_sta->stay_in_tbl) {
 947                 if (info->flags & IEEE80211_TX_STAT_AMPDU) {
 948                         lq_sta->total_success += info->status.ampdu_ack_map;
 949                         lq_sta->total_failed +=
 950                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
 951                 } else {
 952                         if (status)
 953                                 lq_sta->total_success++;
 954                         else
 955                                 lq_sta->total_failed++;
 956                 }
 957         }
 958
 959         /* See if there's a better rate or modulation mode to try. */
 960         if (sta && sta->supp_rates[sband->band])
 961                 rs_rate_scale_perform(priv, hdr, sta, lq_sta);
 962 out:
 963         return;
 964 }
 965
 966 /*
 967  * Begin a period of staying with a selected modulation mode.
 968  * Set "stay_in_tbl" flag to prevent any mode switches.
 969  * Set frame tx success limits according to legacy vs. high-throughput,
 970  * and reset overall (spanning all rates) tx success history statistics.
 971  * These control how long we stay using same modulation mode before
 972  * searching for a new mode.
 973  */
 974 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
 975                                  struct iwl_lq_sta *lq_sta)
 976 {
 977         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
 978         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
 979         if (is_legacy) {
 980                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
 981                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
 982                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
 983         } else {
 984                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
 985                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
 986                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
 987         }
 988         lq_sta->table_count = 0;
 989         lq_sta->total_failed = 0;
 990         lq_sta->total_success = 0;
 991 }
 992
 993 /*
 994  * Find correct throughput table for given mode of modulation
 995  */
 996 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
 997                                       struct iwl_scale_tbl_info *tbl)
 998 {
 999         if (is_legacy(tbl->lq_type)) {
1000                 if (!is_a_band(tbl->lq_type))
1001                         tbl->expected_tpt = expected_tpt_G;
1002                 else
1003                         tbl->expected_tpt = expected_tpt_A;
1004         } else if (is_siso(tbl->lq_type)) {
1005                 if (tbl->is_fat && !lq_sta->is_dup)
1006                         if (tbl->is_SGI)
1007                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
1008                         else
1009                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1010                 else if (tbl->is_SGI)
1011                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1012                 else
1013                         tbl->expected_tpt = expected_tpt_siso20MHz;
1014
1015         } else if (is_mimo(tbl->lq_type)) { /* FIXME:need to separate mimo2/3 */
1016                 if (tbl->is_fat && !lq_sta->is_dup)
1017                         if (tbl->is_SGI)
1018                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
1019                         else
1020                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
1021                 else if (tbl->is_SGI)
1022                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
1023                 else
1024                         tbl->expected_tpt = expected_tpt_mimo20MHz;
1025         } else
1026                 tbl->expected_tpt = expected_tpt_G;
1027 }
1028
1029 /*
1030  * Find starting rate for new "search" high-throughput mode of modulation.
1031  * Goal is to find lowest expected rate (under perfect conditions) that is
1032  * above the current measured throughput of "active" mode, to give new mode
1033  * a fair chance to prove itself without too many challenges.
1034  *
1035  * This gets called when transitioning to more aggressive modulation
1036  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1037  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1038  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1039  * bit rate will typically need to increase, but not if performance was bad.
1040  */
1041 static s32 rs_get_best_rate(struct iwl_priv *priv,
1042                             struct iwl_lq_sta *lq_sta,
1043                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1044                             u16 rate_mask, s8 index)
1045 {
1046         /* "active" values */
1047         struct iwl_scale_tbl_info *active_tbl =
1048             &(lq_sta->lq_info[lq_sta->active_tbl]);
1049         s32 active_sr = active_tbl->win[index].success_ratio;
1050         s32 active_tpt = active_tbl->expected_tpt[index];
1051
1052         /* expected "search" throughput */
1053         s32 *tpt_tbl = tbl->expected_tpt;
1054
1055         s32 new_rate, high, low, start_hi;
1056         u16 high_low;
1057         s8 rate = index;
1058
1059         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1060
1061         for (; ;) {
1062                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1063                                                 tbl->lq_type);
1064
1065                 low = high_low & 0xff;
1066                 high = (high_low >> 8) & 0xff;
1067
1068                 /*
1069                  * Lower the "search" bit rate, to give new "search" mode
1070                  * approximately the same throughput as "active" if:
1071                  *
1072                  * 1) "Active" mode has been working modestly well (but not
1073                  *    great), and expected "search" throughput (under perfect
1074                  *    conditions) at candidate rate is above the actual
1075                  *    measured "active" throughput (but less than expected
1076                  *    "active" throughput under perfect conditions).
1077                  * OR
1078                  * 2) "Active" mode has been working perfectly or very well
1079                  *    and expected "search" throughput (under perfect
1080                  *    conditions) at candidate rate is above expected
1081                  *    "active" throughput (under perfect conditions).
1082                  */
1083                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1084                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1085                       (active_sr <= IWL_RATE_HIGH_TH) &&
1086                       (tpt_tbl[rate] <= active_tpt))) ||
1087                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1088                      (tpt_tbl[rate] > active_tpt))) {
1089
1090                         /* (2nd or later pass)
1091                          * If we've already tried to raise the rate, and are
1092                          * now trying to lower it, use the higher rate. */
1093                         if (start_hi != IWL_RATE_INVALID) {
1094                                 new_rate = start_hi;
1095                                 break;
1096                         }
1097
1098                         new_rate = rate;
1099
1100                         /* Loop again with lower rate */
1101                         if (low != IWL_RATE_INVALID)
1102                                 rate = low;
1103
1104                         /* Lower rate not available, use the original */
1105                         else
1106                                 break;
1107
1108                 /* Else try to raise the "search" rate to match "active" */
1109                 } else {
1110                         /* (2nd or later pass)
1111                          * If we've already tried to lower the rate, and are
1112                          * now trying to raise it, use the lower rate. */
1113                         if (new_rate != IWL_RATE_INVALID)
1114                                 break;
1115
1116                         /* Loop again with higher rate */
1117                         else if (high != IWL_RATE_INVALID) {
1118                                 start_hi = high;
1119                                 rate = high;
1120
1121                         /* Higher rate not available, use the original */
1122                         } else {
1123                                 new_rate = rate;
1124                                 break;
1125                         }
1126                 }
1127         }
1128
1129         return new_rate;
1130 }
1131
1132 /*
1133  * Set up search table for MIMO
1134  */
1135 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1136                              struct iwl_lq_sta *lq_sta,
1137                              struct ieee80211_conf *conf,
1138                              struct ieee80211_sta *sta,
1139                              struct iwl_scale_tbl_info *tbl, int index)
1140 {
1141         u16 rate_mask;
1142         s32 rate;
1143         s8 is_green = lq_sta->is_green;
1144
1145         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1146                 return -1;
1147
1148         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1149                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1150                 return -1;
1151
1152         /* Need both Tx chains/antennas to support MIMO */
1153         if (priv->hw_params.tx_chains_num < 2)
1154                 return -1;
1155
1156         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1157
1158         tbl->lq_type = LQ_MIMO2;
1159         tbl->is_dup = lq_sta->is_dup;
1160         tbl->action = 0;
1161         rate_mask = lq_sta->active_mimo2_rate;
1162
1163         if (priv->current_ht_config.supported_chan_width
1164                                         == IWL_CHANNEL_WIDTH_40MHZ)
1165                 tbl->is_fat = 1;
1166         else
1167                 tbl->is_fat = 0;
1168
1169         /* FIXME: - don't toggle SGI here
1170         if (tbl->is_fat) {
1171                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1172                         tbl->is_SGI = 1;
1173                 else
1174                         tbl->is_SGI = 0;
1175         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1176                 tbl->is_SGI = 1;
1177         else
1178                 tbl->is_SGI = 0;
1179         */
1180
1181         rs_set_expected_tpt_table(lq_sta, tbl);
1182
1183         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1184
1185         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1186
1187         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1188                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1189                                                 rate, rate_mask);
1190                 return -1;
1191         }
1192         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1193
1194         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1195                      tbl->current_rate, is_green);
1196         return 0;
1197 }
1198
1199 /*
1200  * Set up search table for SISO
1201  */
1202 static int rs_switch_to_siso(struct iwl_priv *priv,
1203                              struct iwl_lq_sta *lq_sta,
1204                              struct ieee80211_conf *conf,
1205                              struct ieee80211_sta *sta,
1206                              struct iwl_scale_tbl_info *tbl, int index)
1207 {
1208         u16 rate_mask;
1209         u8 is_green = lq_sta->is_green;
1210         s32 rate;
1211
1212         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1213                 return -1;
1214
1215         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1216
1217         tbl->is_dup = lq_sta->is_dup;
1218         tbl->lq_type = LQ_SISO;
1219         tbl->action = 0;
1220         rate_mask = lq_sta->active_siso_rate;
1221
1222         if (priv->current_ht_config.supported_chan_width
1223             == IWL_CHANNEL_WIDTH_40MHZ)
1224                 tbl->is_fat = 1;
1225         else
1226                 tbl->is_fat = 0;
1227
1228         /* FIXME: - don't toggle SGI here
1229         if (tbl->is_fat) {
1230                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1231                         tbl->is_SGI = 1;
1232                 else
1233                         tbl->is_SGI = 0;
1234         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1235                 tbl->is_SGI = 1;
1236         else
1237                 tbl->is_SGI = 0;
1238         */
1239
1240         if (is_green)
1241                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1242
1243         rs_set_expected_tpt_table(lq_sta, tbl);
1244         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1245
1246         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1247         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1248                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1249                              rate, rate_mask);
1250                 return -1;
1251         }
1252         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1253         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1254                      tbl->current_rate, is_green);
1255         return 0;
1256 }
1257
1258 /*
1259  * Try to switch to new modulation mode from legacy
1260  */
1261 static int rs_move_legacy_other(struct iwl_priv *priv,
1262                                 struct iwl_lq_sta *lq_sta,
1263                                 struct ieee80211_conf *conf,
1264                                 struct ieee80211_sta *sta,
1265                                 int index)
1266 {
1267         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1268         struct iwl_scale_tbl_info *search_tbl =
1269                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1270         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1271         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1272                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1273         u8 start_action = tbl->action;
1274         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1275         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1276         int ret = 0;
1277
1278         for (; ;) {
1279                 switch (tbl->action) {
1280                 case IWL_LEGACY_SWITCH_ANTENNA1:
1281                 case IWL_LEGACY_SWITCH_ANTENNA2:
1282                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1283
1284                         lq_sta->action_counter++;
1285
1286                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1287                                                         tx_chains_num <= 1) ||
1288                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1289                                                         tx_chains_num <= 2))
1290                                 break;
1291
1292                         /* Don't change antenna if success has been great */
1293                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1294                                 break;
1295
1296                         /* Set up search table to try other antenna */
1297                         memcpy(search_tbl, tbl, sz);
1298
1299                         if (rs_toggle_antenna(valid_tx_ant,
1300                                 &search_tbl->current_rate, search_tbl)) {
1301                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1302                                 goto out;
1303                         }
1304                         break;
1305                 case IWL_LEGACY_SWITCH_SISO:
1306                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1307
1308                         /* Set up search table to try SISO */
1309                         memcpy(search_tbl, tbl, sz);
1310                         search_tbl->is_SGI = 0;
1311                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1312                                                  search_tbl, index);
1313                         if (!ret) {
1314                                 lq_sta->action_counter = 0;
1315                                 goto out;
1316                         }
1317
1318                         break;
1319                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1320                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1321                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1322                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1323
1324                         /* Set up search table to try MIMO */
1325                         memcpy(search_tbl, tbl, sz);
1326                         search_tbl->is_SGI = 0;
1327
1328                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1329                                 search_tbl->ant_type = ANT_AB;
1330                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1331                                 search_tbl->ant_type = ANT_AC;
1332                         else
1333                                 search_tbl->ant_type = ANT_BC;
1334
1335                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1336                                 break;
1337
1338                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1339                                                  search_tbl, index);
1340                         if (!ret) {
1341                                 lq_sta->action_counter = 0;
1342                                 goto out;
1343                         }
1344                         break;
1345                 }
1346                 tbl->action++;
1347                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1348                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1349
1350                 if (tbl->action == start_action)
1351                         break;
1352
1353         }
1354         search_tbl->lq_type = LQ_NONE;
1355         return 0;
1356
1357 out:
1358         lq_sta->search_better_tbl = 1;
1359         tbl->action++;
1360         if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1361                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1362         return 0;
1363
1364 }
1365
1366 /*
1367  * Try to switch to new modulation mode from SISO
1368  */
1369 static int rs_move_siso_to_other(struct iwl_priv *priv,
1370                                  struct iwl_lq_sta *lq_sta,
1371                                  struct ieee80211_conf *conf,
1372                                  struct ieee80211_sta *sta, int index)
1373 {
1374         u8 is_green = lq_sta->is_green;
1375         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1376         struct iwl_scale_tbl_info *search_tbl =
1377                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1378         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1379         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1380                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1381         u8 start_action = tbl->action;
1382         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1383         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1384         int ret;
1385
1386         for (;;) {
1387                 lq_sta->action_counter++;
1388                 switch (tbl->action) {
1389                 case IWL_SISO_SWITCH_ANTENNA1:
1390                 case IWL_SISO_SWITCH_ANTENNA2:
1391                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1392
1393                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1394                                                         tx_chains_num <= 1) ||
1395                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1396                                                         tx_chains_num <= 2))
1397                                 break;
1398
1399                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1400                                 break;
1401
1402                         memcpy(search_tbl, tbl, sz);
1403                         if (rs_toggle_antenna(valid_tx_ant,
1404                                        &search_tbl->current_rate, search_tbl))
1405                                 goto out;
1406                         break;
1407                 case IWL_SISO_SWITCH_MIMO2_AB:
1408                 case IWL_SISO_SWITCH_MIMO2_AC:
1409                 case IWL_SISO_SWITCH_MIMO2_BC:
1410                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1411                         memcpy(search_tbl, tbl, sz);
1412                         search_tbl->is_SGI = 0;
1413
1414                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1415                                 search_tbl->ant_type = ANT_AB;
1416                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1417                                 search_tbl->ant_type = ANT_AC;
1418                         else
1419                                 search_tbl->ant_type = ANT_BC;
1420
1421                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1422                                 break;
1423
1424                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1425                                                  search_tbl, index);
1426                         if (!ret)
1427                                 goto out;
1428                         break;
1429                 case IWL_SISO_SWITCH_GI:
1430                         if (!tbl->is_fat &&
1431                                 !(priv->current_ht_config.sgf &
1432                                                 HT_SHORT_GI_20MHZ))
1433                                 break;
1434                         if (tbl->is_fat &&
1435                                 !(priv->current_ht_config.sgf &
1436                                                 HT_SHORT_GI_40MHZ))
1437                                 break;
1438
1439                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1440
1441                         memcpy(search_tbl, tbl, sz);
1442                         if (is_green) {
1443                                 if (!tbl->is_SGI)
1444                                         break;
1445                                 else
1446                                         IWL_ERR(priv,
1447                                                 "SGI was set in GF+SISO\n");
1448                         }
1449                         search_tbl->is_SGI = !tbl->is_SGI;
1450                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1451                         if (tbl->is_SGI) {
1452                                 s32 tpt = lq_sta->last_tpt / 100;
1453                                 if (tpt >= search_tbl->expected_tpt[index])
1454                                         break;
1455                         }
1456                         search_tbl->current_rate =
1457                                 rate_n_flags_from_tbl(priv, search_tbl,
1458                                                       index, is_green);
1459                         goto out;
1460                 }
1461                 tbl->action++;
1462                 if (tbl->action > IWL_SISO_SWITCH_GI)
1463                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1464
1465                 if (tbl->action == start_action)
1466                         break;
1467         }
1468         search_tbl->lq_type = LQ_NONE;
1469         return 0;
1470
1471  out:
1472         lq_sta->search_better_tbl = 1;
1473         tbl->action++;
1474         if (tbl->action > IWL_SISO_SWITCH_GI)
1475                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1476         return 0;
1477 }
1478
1479 /*
1480  * Try to switch to new modulation mode from MIMO
1481  */
1482 static int rs_move_mimo_to_other(struct iwl_priv *priv,
1483                                  struct iwl_lq_sta *lq_sta,
1484                                  struct ieee80211_conf *conf,
1485                                  struct ieee80211_sta *sta, int index)
1486 {
1487         s8 is_green = lq_sta->is_green;
1488         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1489         struct iwl_scale_tbl_info *search_tbl =
1490                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1491         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1492         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1493                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1494         u8 start_action = tbl->action;
1495         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1496         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1497         int ret;
1498
1499         for (;;) {
1500                 lq_sta->action_counter++;
1501                 switch (tbl->action) {
1502                 case IWL_MIMO2_SWITCH_ANTENNA1:
1503                 case IWL_MIMO2_SWITCH_ANTENNA2:
1504                         IWL_DEBUG_RATE(priv, "LQ: MIMO toggle Antennas\n");
1505
1506                         if (tx_chains_num <= 2)
1507                                 break;
1508
1509                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1510                                 break;
1511
1512                         memcpy(search_tbl, tbl, sz);
1513                         if (rs_toggle_antenna(valid_tx_ant,
1514                                        &search_tbl->current_rate, search_tbl))
1515                                 goto out;
1516                         break;
1517                 case IWL_MIMO2_SWITCH_SISO_A:
1518                 case IWL_MIMO2_SWITCH_SISO_B:
1519                 case IWL_MIMO2_SWITCH_SISO_C:
1520                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1521
1522                         /* Set up new search table for SISO */
1523                         memcpy(search_tbl, tbl, sz);
1524
1525                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1526                                 search_tbl->ant_type = ANT_A;
1527                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1528                                 search_tbl->ant_type = ANT_B;
1529                         else
1530                                 search_tbl->ant_type = ANT_C;
1531
1532                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1533                                 break;
1534
1535                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1536                                                  search_tbl, index);
1537                         if (!ret)
1538                                 goto out;
1539
1540                         break;
1541
1542                 case IWL_MIMO2_SWITCH_GI:
1543                         if (!tbl->is_fat &&
1544                                 !(priv->current_ht_config.sgf &
1545                                                 HT_SHORT_GI_20MHZ))
1546                                 break;
1547                         if (tbl->is_fat &&
1548                                 !(priv->current_ht_config.sgf &
1549                                                 HT_SHORT_GI_40MHZ))
1550                                 break;
1551
1552                         IWL_DEBUG_RATE(priv, "LQ: MIMO toggle SGI/NGI\n");
1553
1554                         /* Set up new search table for MIMO */
1555                         memcpy(search_tbl, tbl, sz);
1556                         search_tbl->is_SGI = !tbl->is_SGI;
1557                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1558                         /*
1559                          * If active table already uses the fastest possible
1560                          * modulation (dual stream with short guard interval),
1561                          * and it's working well, there's no need to look
1562                          * for a better type of modulation!
1563                          */
1564                         if (tbl->is_SGI) {
1565                                 s32 tpt = lq_sta->last_tpt / 100;
1566                                 if (tpt >= search_tbl->expected_tpt[index])
1567                                         break;
1568                         }
1569                         search_tbl->current_rate =
1570                                 rate_n_flags_from_tbl(priv, search_tbl,
1571                                                       index, is_green);
1572                         goto out;
1573
1574                 }
1575                 tbl->action++;
1576                 if (tbl->action > IWL_MIMO2_SWITCH_GI)
1577                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1578
1579                 if (tbl->action == start_action)
1580                         break;
1581         }
1582         search_tbl->lq_type = LQ_NONE;
1583         return 0;
1584  out:
1585         lq_sta->search_better_tbl = 1;
1586         tbl->action++;
1587         if (tbl->action > IWL_MIMO2_SWITCH_GI)
1588                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1589         return 0;
1590
1591 }
1592
1593 /*
1594  * Check whether we should continue using same modulation mode, or
1595  * begin search for a new mode, based on:
1596  * 1) # tx successes or failures while using this mode
1597  * 2) # times calling this function
1598  * 3) elapsed time in this mode (not used, for now)
1599  */
1600 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1601 {
1602         struct iwl_scale_tbl_info *tbl;
1603         int i;
1604         int active_tbl;
1605         int flush_interval_passed = 0;
1606         struct iwl_priv *priv;
1607
1608         priv = lq_sta->drv;
1609         active_tbl = lq_sta->active_tbl;
1610
1611         tbl = &(lq_sta->lq_info[active_tbl]);
1612
1613         /* If we've been disallowing search, see if we should now allow it */
1614         if (lq_sta->stay_in_tbl) {
1615
1616                 /* Elapsed time using current modulation mode */
1617                 if (lq_sta->flush_timer)
1618                         flush_interval_passed =
1619                             time_after(jiffies,
1620                                        (unsigned long)(lq_sta->flush_timer +
1621                                         IWL_RATE_SCALE_FLUSH_INTVL));
1622
1623                 /*
1624                  * Check if we should allow search for new modulation mode.
1625                  * If many frames have failed or succeeded, or we've used
1626                  * this same modulation for a long time, allow search, and
1627                  * reset history stats that keep track of whether we should
1628                  * allow a new search.  Also (below) reset all bitmaps and
1629                  * stats in active history.
1630                  */
1631                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1632                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1633                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1634                      && (flush_interval_passed))) {
1635                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1636                                      lq_sta->total_failed,
1637                                      lq_sta->total_success,
1638                                      flush_interval_passed);
1639
1640                         /* Allow search for new mode */
1641                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1642                         lq_sta->total_failed = 0;
1643                         lq_sta->total_success = 0;
1644                         lq_sta->flush_timer = 0;
1645
1646                 /*
1647                  * Else if we've used this modulation mode enough repetitions
1648                  * (regardless of elapsed time or success/failure), reset
1649                  * history bitmaps and rate-specific stats for all rates in
1650                  * active table.
1651                  */
1652                 } else {
1653                         lq_sta->table_count++;
1654                         if (lq_sta->table_count >=
1655                             lq_sta->table_count_limit) {
1656                                 lq_sta->table_count = 0;
1657
1658                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
1659                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1660                                         rs_rate_scale_clear_window(
1661                                                 &(tbl->win[i]));
1662                         }
1663                 }
1664
1665                 /* If transitioning to allow "search", reset all history
1666                  * bitmaps and stats in active table (this will become the new
1667                  * "search" table). */
1668                 if (!lq_sta->stay_in_tbl) {
1669                         for (i = 0; i < IWL_RATE_COUNT; i++)
1670                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1671                 }
1672         }
1673 }
1674
1675 /*
1676  * Do rate scaling and search for new modulation mode.
1677  */
1678 static void rs_rate_scale_perform(struct iwl_priv *priv,
1679                                   struct ieee80211_hdr *hdr,
1680                                   struct ieee80211_sta *sta,
1681                                   struct iwl_lq_sta *lq_sta)
1682 {
1683         struct ieee80211_hw *hw = priv->hw;
1684         struct ieee80211_conf *conf = &hw->conf;
1685         int low = IWL_RATE_INVALID;
1686         int high = IWL_RATE_INVALID;
1687         int index;
1688         int i;
1689         struct iwl_rate_scale_data *window = NULL;
1690         int current_tpt = IWL_INVALID_VALUE;
1691         int low_tpt = IWL_INVALID_VALUE;
1692         int high_tpt = IWL_INVALID_VALUE;
1693         u32 fail_count;
1694         s8 scale_action = 0;
1695         u16 rate_mask;
1696         u8 update_lq = 0;
1697         struct iwl_scale_tbl_info *tbl, *tbl1;
1698         u16 rate_scale_index_msk = 0;
1699         u32 rate;
1700         u8 is_green = 0;
1701         u8 active_tbl = 0;
1702         u8 done_search = 0;
1703         u16 high_low;
1704         s32 sr;
1705         u8 tid = MAX_TID_COUNT;
1706         struct iwl_tid_data *tid_data;
1707
1708         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
1709
1710         /* Send management frames and broadcast/multicast data using
1711          * lowest rate. */
1712         /* TODO: this could probably be improved.. */
1713         if (!ieee80211_is_data(hdr->frame_control) ||
1714             is_multicast_ether_addr(hdr->addr1))
1715                 return;
1716
1717         if (!sta || !lq_sta)
1718                 return;
1719
1720         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1721
1722         tid = rs_tl_add_packet(lq_sta, hdr);
1723
1724         /*
1725          * Select rate-scale / modulation-mode table to work with in
1726          * the rest of this function:  "search" if searching for better
1727          * modulation mode, or "active" if doing rate scaling within a mode.
1728          */
1729         if (!lq_sta->search_better_tbl)
1730                 active_tbl = lq_sta->active_tbl;
1731         else
1732                 active_tbl = 1 - lq_sta->active_tbl;
1733
1734         tbl = &(lq_sta->lq_info[active_tbl]);
1735         is_green = lq_sta->is_green;
1736
1737         /* current tx rate */
1738         index = lq_sta->last_txrate_idx;
1739
1740         IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
1741                        tbl->lq_type);
1742
1743         /* rates available for this association, and for modulation mode */
1744         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1745
1746         IWL_DEBUG_RATE(priv, "mask 0x%04X \n", rate_mask);
1747
1748         /* mask with station rate restriction */
1749         if (is_legacy(tbl->lq_type)) {
1750                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
1751                         /* supp_rates has no CCK bits in A mode */
1752                         rate_scale_index_msk = (u16) (rate_mask &
1753                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1754                 else
1755                         rate_scale_index_msk = (u16) (rate_mask &
1756                                                       lq_sta->supp_rates);
1757
1758         } else
1759                 rate_scale_index_msk = rate_mask;
1760
1761         if (!rate_scale_index_msk)
1762                 rate_scale_index_msk = rate_mask;
1763
1764         if (!((1 << index) & rate_scale_index_msk)) {
1765                 IWL_ERR(priv, "Current Rate is not valid\n");
1766                 return;
1767         }
1768
1769         /* Get expected throughput table and history window for current rate */
1770         if (!tbl->expected_tpt) {
1771                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
1772                 return;
1773         }
1774
1775         /* force user max rate if set by user */
1776         if ((lq_sta->max_rate_idx != -1) &&
1777             (lq_sta->max_rate_idx < index)) {
1778                 index = lq_sta->max_rate_idx;
1779                 update_lq = 1;
1780                 window = &(tbl->win[index]);
1781                 goto lq_update;
1782         }
1783
1784         window = &(tbl->win[index]);
1785
1786         /*
1787          * If there is not enough history to calculate actual average
1788          * throughput, keep analyzing results of more tx frames, without
1789          * changing rate or mode (bypass most of the rest of this function).
1790          * Set up new rate table in uCode only if old rate is not supported
1791          * in current association (use new rate found above).
1792          */
1793         fail_count = window->counter - window->success_counter;
1794         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1795                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
1796                 IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
1797                                "for index %d\n",
1798                                window->success_counter, window->counter, index);
1799
1800                 /* Can't calculate this yet; not enough history */
1801                 window->average_tpt = IWL_INVALID_VALUE;
1802
1803                 /* Should we stay with this modulation mode,
1804                  * or search for a new one? */
1805                 rs_stay_in_table(lq_sta);
1806
1807                 goto out;
1808         }
1809
1810         /* Else we have enough samples; calculate estimate of
1811          * actual average throughput */
1812
1813         BUG_ON(window->average_tpt != ((window->success_ratio *
1814                         tbl->expected_tpt[index] + 64) / 128));
1815
1816         /* If we are searching for better modulation mode, check success. */
1817         if (lq_sta->search_better_tbl) {
1818
1819                 /* If good success, continue using the "search" mode;
1820                  * no need to send new link quality command, since we're
1821                  * continuing to use the setup that we've been trying. */
1822                 if (window->average_tpt > lq_sta->last_tpt) {
1823
1824                         IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
1825                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1826                                         window->success_ratio,
1827                                         window->average_tpt,
1828                                         lq_sta->last_tpt);
1829
1830                         if (!is_legacy(tbl->lq_type))
1831                                 lq_sta->enable_counter = 1;
1832
1833                         /* Swap tables; "search" becomes "active" */
1834                         lq_sta->active_tbl = active_tbl;
1835                         current_tpt = window->average_tpt;
1836
1837                 /* Else poor success; go back to mode in "active" table */
1838                 } else {
1839
1840                         IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
1841                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1842                                         window->success_ratio,
1843                                         window->average_tpt,
1844                                         lq_sta->last_tpt);
1845
1846                         /* Nullify "search" table */
1847                         tbl->lq_type = LQ_NONE;
1848
1849                         /* Revert to "active" table */
1850                         active_tbl = lq_sta->active_tbl;
1851                         tbl = &(lq_sta->lq_info[active_tbl]);
1852
1853                         /* Revert to "active" rate and throughput info */
1854                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1855                         current_tpt = lq_sta->last_tpt;
1856
1857                         /* Need to set up a new rate table in uCode */
1858                         update_lq = 1;
1859                 }
1860
1861                 /* Either way, we've made a decision; modulation mode
1862                  * search is done, allow rate adjustment next time. */
1863                 lq_sta->search_better_tbl = 0;
1864                 done_search = 1;        /* Don't switch modes below! */
1865                 goto lq_update;
1866         }
1867
1868         /* (Else) not in search of better modulation mode, try for better
1869          * starting rate, while staying in this mode. */
1870         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
1871                                         tbl->lq_type);
1872         low = high_low & 0xff;
1873         high = (high_low >> 8) & 0xff;
1874
1875         /* If user set max rate, dont allow higher than user constrain */
1876         if ((lq_sta->max_rate_idx != -1) &&
1877             (lq_sta->max_rate_idx < high))
1878                 high = IWL_RATE_INVALID;
1879
1880         sr = window->success_ratio;
1881
1882         /* Collect measured throughputs for current and adjacent rates */
1883         current_tpt = window->average_tpt;
1884         if (low != IWL_RATE_INVALID)
1885                 low_tpt = tbl->win[low].average_tpt;
1886         if (high != IWL_RATE_INVALID)
1887                 high_tpt = tbl->win[high].average_tpt;
1888
1889         scale_action = 0;
1890
1891         /* Too many failures, decrease rate */
1892         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
1893                 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
1894                 scale_action = -1;
1895
1896         /* No throughput measured yet for adjacent rates; try increase. */
1897         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1898                    (high_tpt == IWL_INVALID_VALUE)) {
1899
1900                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
1901                         scale_action = 1;
1902                 else if (low != IWL_RATE_INVALID)
1903                         scale_action = 0;
1904         }
1905
1906         /* Both adjacent throughputs are measured, but neither one has better
1907          * throughput; we're using the best rate, don't change it! */
1908         else if ((low_tpt != IWL_INVALID_VALUE) &&
1909                  (high_tpt != IWL_INVALID_VALUE) &&
1910                  (low_tpt < current_tpt) &&
1911                  (high_tpt < current_tpt))
1912                 scale_action = 0;
1913
1914         /* At least one adjacent rate's throughput is measured,
1915          * and may have better performance. */
1916         else {
1917                 /* Higher adjacent rate's throughput is measured */
1918                 if (high_tpt != IWL_INVALID_VALUE) {
1919                         /* Higher rate has better throughput */
1920                         if (high_tpt > current_tpt &&
1921                                         sr >= IWL_RATE_INCREASE_TH) {
1922                                 scale_action = 1;
1923                         } else {
1924                                 scale_action = 0;
1925                         }
1926
1927                 /* Lower adjacent rate's throughput is measured */
1928                 } else if (low_tpt != IWL_INVALID_VALUE) {
1929                         /* Lower rate has better throughput */
1930                         if (low_tpt > current_tpt) {
1931                                 IWL_DEBUG_RATE(priv,
1932                                     "decrease rate because of low tpt\n");
1933                                 scale_action = -1;
1934                         } else if (sr >= IWL_RATE_INCREASE_TH) {
1935                                 scale_action = 1;
1936                         }
1937                 }
1938         }
1939
1940         /* Sanity check; asked for decrease, but success rate or throughput
1941          * has been good at old rate.  Don't change it. */
1942         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
1943                     ((sr > IWL_RATE_HIGH_TH) ||
1944                      (current_tpt > (100 * tbl->expected_tpt[low]))))
1945                 scale_action = 0;
1946
1947         switch (scale_action) {
1948         case -1:
1949                 /* Decrease starting rate, update uCode's rate table */
1950                 if (low != IWL_RATE_INVALID) {
1951                         update_lq = 1;
1952                         index = low;
1953                 }
1954                 break;
1955         case 1:
1956                 /* Increase starting rate, update uCode's rate table */
1957                 if (high != IWL_RATE_INVALID) {
1958                         update_lq = 1;
1959                         index = high;
1960                 }
1961
1962                 break;
1963         case 0:
1964                 /* No change */
1965         default:
1966                 break;
1967         }
1968
1969         IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
1970                     "high %d type %d\n",
1971                      index, scale_action, low, high, tbl->lq_type);
1972
1973 lq_update:
1974         /* Replace uCode's rate table for the destination station. */
1975         if (update_lq) {
1976                 rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
1977                 rs_fill_link_cmd(priv, lq_sta, rate);
1978                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1979         }
1980
1981         /* Should we stay with this modulation mode, or search for a new one? */
1982         rs_stay_in_table(lq_sta);
1983
1984         /*
1985          * Search for new modulation mode if we're:
1986          * 1)  Not changing rates right now
1987          * 2)  Not just finishing up a search
1988          * 3)  Allowing a new search
1989          */
1990         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
1991                 /* Save current throughput to compare with "search" throughput*/
1992                 lq_sta->last_tpt = current_tpt;
1993
1994                 /* Select a new "search" modulation mode to try.
1995                  * If one is found, set up the new "search" table. */
1996                 if (is_legacy(tbl->lq_type))
1997                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
1998                 else if (is_siso(tbl->lq_type))
1999                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2000                 else
2001                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
2002
2003                 /* If new "search" mode was selected, set up in uCode table */
2004                 if (lq_sta->search_better_tbl) {
2005                         /* Access the "search" table, clear its history. */
2006                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2007                         for (i = 0; i < IWL_RATE_COUNT; i++)
2008                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2009
2010                         /* Use new "search" start rate */
2011                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2012
2013                         IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
2014                                      tbl->current_rate, index);
2015                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
2016                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2017                 }
2018
2019                 /* If the "active" (non-search) mode was legacy,
2020                  * and we've tried switching antennas,
2021                  * but we haven't been able to try HT modes (not available),
2022                  * stay with best antenna legacy modulation for a while
2023                  * before next round of mode comparisons. */
2024                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2025                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2026                     lq_sta->action_counter >= 1) {
2027                         lq_sta->action_counter = 0;
2028                         IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2029                         rs_set_stay_in_table(priv, 1, lq_sta);
2030                 }
2031
2032                 /* If we're in an HT mode, and all 3 mode switch actions
2033                  * have been tried and compared, stay in this best modulation
2034                  * mode for a while before next round of mode comparisons. */
2035                 if (lq_sta->enable_counter &&
2036                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
2037                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2038                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2039                             (tid != MAX_TID_COUNT)) {
2040                                 tid_data =
2041                                    &priv->stations[lq_sta->lq.sta_id].tid[tid];
2042                                 if (tid_data->agg.state == IWL_AGG_OFF) {
2043                                         IWL_DEBUG_RATE(priv,
2044                                                        "try to aggregate tid %d\n",
2045                                                        tid);
2046                                         rs_tl_turn_on_agg(priv, tid,
2047                                                           lq_sta, sta);
2048                                 }
2049                         }
2050                         lq_sta->action_counter = 0;
2051                         rs_set_stay_in_table(priv, 0, lq_sta);
2052                 }
2053
2054         /*
2055          * Else, don't search for a new modulation mode.
2056          * Put new timestamp in stay-in-modulation-mode flush timer if:
2057          * 1)  Not changing rates right now
2058          * 2)  Not just finishing up a search
2059          * 3)  flush timer is empty
2060          */
2061         } else {
2062                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
2063                         lq_sta->flush_timer = jiffies;
2064         }
2065
2066 out:
2067         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2068         i = index;
2069         lq_sta->last_txrate_idx = i;
2070
2071         return;
2072 }
2073
2074
2075 static void rs_initialize_lq(struct iwl_priv *priv,
2076                              struct ieee80211_conf *conf,
2077                              struct ieee80211_sta *sta,
2078                              struct iwl_lq_sta *lq_sta)
2079 {
2080         struct iwl_scale_tbl_info *tbl;
2081         int rate_idx;
2082         int i;
2083         u32 rate;
2084         u8 use_green = rs_use_green(priv, conf);
2085         u8 active_tbl = 0;
2086         u8 valid_tx_ant;
2087
2088         if (!sta || !lq_sta)
2089                 goto out;
2090
2091         i = lq_sta->last_txrate_idx;
2092
2093         if ((lq_sta->lq.sta_id == 0xff) &&
2094             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2095                 goto out;
2096
2097         valid_tx_ant = priv->hw_params.valid_tx_ant;
2098
2099         if (!lq_sta->search_better_tbl)
2100                 active_tbl = lq_sta->active_tbl;
2101         else
2102                 active_tbl = 1 - lq_sta->active_tbl;
2103
2104         tbl = &(lq_sta->lq_info[active_tbl]);
2105
2106         if ((i < 0) || (i >= IWL_RATE_COUNT))
2107                 i = 0;
2108
2109         rate = iwl_rates[i].plcp;
2110         tbl->ant_type = first_antenna(valid_tx_ant);
2111         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2112
2113         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2114                 rate |= RATE_MCS_CCK_MSK;
2115
2116         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2117         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2118             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2119
2120         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2121         tbl->current_rate = rate;
2122         rs_set_expected_tpt_table(lq_sta, tbl);
2123         rs_fill_link_cmd(NULL, lq_sta, rate);
2124         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2125  out:
2126         return;
2127 }
2128
2129 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2130                         struct ieee80211_tx_rate_control *txrc)
2131 {
2132
2133         struct sk_buff *skb = txrc->skb;
2134         struct ieee80211_supported_band *sband = txrc->sband;
2135         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2136         struct ieee80211_conf *conf = &priv->hw->conf;
2137         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2138         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2139         struct iwl_lq_sta *lq_sta = priv_sta;
2140         int rate_idx;
2141         u64 mask_bit = 0;
2142
2143         IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2144
2145         /* Get max rate if user set max rate */
2146         if (lq_sta) {
2147                 lq_sta->max_rate_idx = txrc->max_rate_idx;
2148                 if ((sband->band == IEEE80211_BAND_5GHZ) &&
2149                     (lq_sta->max_rate_idx != -1))
2150                         lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2151                 if ((lq_sta->max_rate_idx < 0) ||
2152                     (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2153                         lq_sta->max_rate_idx = -1;
2154         }
2155
2156         if (sta)
2157                 mask_bit = sta->supp_rates[sband->band];
2158
2159         /* Send management frames and broadcast/multicast data using lowest
2160          * rate. */
2161         if (!ieee80211_is_data(hdr->frame_control) ||
2162             is_multicast_ether_addr(hdr->addr1) || !sta || !lq_sta) {
2163                 if (!mask_bit)
2164                         info->control.rates[0].idx =
2165                                         rate_lowest_index(sband, NULL);
2166                 else
2167                         info->control.rates[0].idx =
2168                                         rate_lowest_index(sband, sta);
2169                 return;
2170         }
2171
2172         rate_idx  = lq_sta->last_txrate_idx;
2173
2174         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2175             !lq_sta->ibss_sta_added) {
2176                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2177
2178                 if (sta_id == IWL_INVALID_STATION) {
2179                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
2180                                        hdr->addr1);
2181                         sta_id = iwl_add_station_flags(priv, hdr->addr1,
2182                                                         0, CMD_ASYNC, NULL);
2183                 }
2184                 if ((sta_id != IWL_INVALID_STATION)) {
2185                         lq_sta->lq.sta_id = sta_id;
2186                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2187                         lq_sta->ibss_sta_added = 1;
2188                         rs_initialize_lq(priv, conf, sta, lq_sta);
2189                 }
2190         }
2191
2192         if (rate_idx < 0 || rate_idx > IWL_RATE_COUNT)
2193                 rate_idx = rate_lowest_index(sband, sta);
2194         else if (sband->band == IEEE80211_BAND_5GHZ)
2195                 rate_idx -= IWL_FIRST_OFDM_RATE;
2196
2197         info->control.rates[0].idx = rate_idx;
2198 }
2199
2200 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2201                           gfp_t gfp)
2202 {
2203         struct iwl_lq_sta *lq_sta;
2204         struct iwl_priv *priv;
2205         int i, j;
2206
2207         priv = (struct iwl_priv *)priv_rate;
2208         IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2209
2210         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2211
2212         if (lq_sta == NULL)
2213                 return NULL;
2214         lq_sta->lq.sta_id = 0xff;
2215
2216
2217         for (j = 0; j < LQ_SIZE; j++)
2218                 for (i = 0; i < IWL_RATE_COUNT; i++)
2219                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2220
2221         return lq_sta;
2222 }
2223
2224 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2225                          struct ieee80211_sta *sta, void *priv_sta)
2226 {
2227         int i, j;
2228         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2229         struct ieee80211_conf *conf = &priv->hw->conf;
2230         struct iwl_lq_sta *lq_sta = priv_sta;
2231         u16 mask_bit = 0;
2232         int count;
2233         int start_rate = 0;
2234
2235         lq_sta->flush_timer = 0;
2236         lq_sta->supp_rates = sta->supp_rates[sband->band];
2237         for (j = 0; j < LQ_SIZE; j++)
2238                 for (i = 0; i < IWL_RATE_COUNT; i++)
2239                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2240
2241         IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init ***\n");
2242         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2243          * the lowest or the highest rate.. Could consider using RSSI from
2244          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2245          * after assoc.. */
2246
2247         lq_sta->ibss_sta_added = 0;
2248         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2249                 u8 sta_id = iwl_find_station(priv, sta->addr);
2250
2251                 /* for IBSS the call are from tasklet */
2252                 IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2253
2254                 if (sta_id == IWL_INVALID_STATION) {
2255                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2256                         sta_id = iwl_add_station_flags(priv, sta->addr,
2257                                                         0, CMD_ASYNC, NULL);
2258                 }
2259                 if ((sta_id != IWL_INVALID_STATION)) {
2260                         lq_sta->lq.sta_id = sta_id;
2261                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2262                 }
2263                 /* FIXME: this is w/a remove it later */
2264                 priv->assoc_station_added = 1;
2265         }
2266
2267         lq_sta->is_dup = 0;
2268         lq_sta->max_rate_idx = -1;
2269         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2270         lq_sta->is_green = rs_use_green(priv, conf);
2271         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2272         lq_sta->active_rate_basic = priv->active_rate_basic;
2273         lq_sta->band = priv->band;
2274         /*
2275          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2276          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2277          */
2278         lq_sta->active_siso_rate = sta->ht_cap.mcs.rx_mask[0] << 1;
2279         lq_sta->active_siso_rate |= sta->ht_cap.mcs.rx_mask[0] & 0x1;
2280         lq_sta->active_siso_rate &= ~((u16)0x2);
2281         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2282
2283         /* Same here */
2284         lq_sta->active_mimo2_rate = sta->ht_cap.mcs.rx_mask[1] << 1;
2285         lq_sta->active_mimo2_rate |= sta->ht_cap.mcs.rx_mask[1] & 0x1;
2286         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2287         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2288
2289         lq_sta->active_mimo3_rate = sta->ht_cap.mcs.rx_mask[2] << 1;
2290         lq_sta->active_mimo3_rate |= sta->ht_cap.mcs.rx_mask[2] & 0x1;
2291         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2292         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2293
2294         IWL_DEBUG_RATE(priv, "SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2295                      lq_sta->active_siso_rate,
2296                      lq_sta->active_mimo2_rate,
2297                      lq_sta->active_mimo3_rate);
2298
2299         /* These values will be overridden later */
2300         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2301         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2302
2303         /* as default allow aggregation for all tids */
2304         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2305         lq_sta->drv = priv;
2306
2307         /* Find highest tx rate supported by hardware and destination station */
2308         mask_bit = sta->supp_rates[sband->band];
2309         count = sband->n_bitrates;
2310         if (sband->band == IEEE80211_BAND_5GHZ) {
2311                 count += IWL_FIRST_OFDM_RATE;
2312                 start_rate = IWL_FIRST_OFDM_RATE;
2313                 mask_bit <<= IWL_FIRST_OFDM_RATE;
2314         }
2315
2316         mask_bit = mask_bit & lq_sta->active_legacy_rate;
2317         lq_sta->last_txrate_idx = 4;
2318         for (i = start_rate; i < count; i++)
2319                 if (mask_bit & BIT(i))
2320                         lq_sta->last_txrate_idx = i;
2321
2322         rs_initialize_lq(priv, conf, sta, lq_sta);
2323 }
2324
2325 static void rs_fill_link_cmd(const struct iwl_priv *priv,
2326                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2327 {
2328         struct iwl_scale_tbl_info tbl_type;
2329         int index = 0;
2330         int rate_idx;
2331         int repeat_rate = 0;
2332         u8 ant_toggle_cnt = 0;
2333         u8 use_ht_possible = 1;
2334         u8 valid_tx_ant = 0;
2335         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2336
2337         /* Override starting rate (index 0) if needed for debug purposes */
2338         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2339
2340         /* Interpret new_rate (rate_n_flags) */
2341         memset(&tbl_type, 0, sizeof(tbl_type));
2342         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2343                                   &tbl_type, &rate_idx);
2344
2345         /* How many times should we repeat the initial rate? */
2346         if (is_legacy(tbl_type.lq_type)) {
2347                 ant_toggle_cnt = 1;
2348                 repeat_rate = IWL_NUMBER_TRY;
2349         } else {
2350                 repeat_rate = IWL_HT_NUMBER_TRY;
2351         }
2352
2353         lq_cmd->general_params.mimo_delimiter =
2354                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2355
2356         /* Fill 1st table entry (index 0) */
2357         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2358
2359         if (num_of_ant(tbl_type.ant_type) == 1) {
2360                 lq_cmd->general_params.single_stream_ant_msk =
2361                                                 tbl_type.ant_type;
2362         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2363                 lq_cmd->general_params.dual_stream_ant_msk =
2364                                                 tbl_type.ant_type;
2365         } /* otherwise we don't modify the existing value */
2366
2367         index++;
2368         repeat_rate--;
2369
2370         if (priv)
2371                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2372
2373         /* Fill rest of rate table */
2374         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2375                 /* Repeat initial/next rate.
2376                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2377                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2378                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2379                         if (is_legacy(tbl_type.lq_type)) {
2380                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2381                                         ant_toggle_cnt++;
2382                                 else if (priv &&
2383                                          rs_toggle_antenna(valid_tx_ant,
2384                                                         &new_rate, &tbl_type))
2385                                         ant_toggle_cnt = 1;
2386 }
2387
2388                         /* Override next rate if needed for debug purposes */
2389                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2390
2391                         /* Fill next table entry */
2392                         lq_cmd->rs_table[index].rate_n_flags =
2393                                         cpu_to_le32(new_rate);
2394                         repeat_rate--;
2395                         index++;
2396                 }
2397
2398                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2399                                                 &rate_idx);
2400
2401                 /* Indicate to uCode which entries might be MIMO.
2402                  * If initial rate was MIMO, this will finally end up
2403                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2404                 if (is_mimo(tbl_type.lq_type))
2405                         lq_cmd->general_params.mimo_delimiter = index;
2406
2407                 /* Get next rate */
2408                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2409                                              use_ht_possible);
2410
2411                 /* How many times should we repeat the next rate? */
2412                 if (is_legacy(tbl_type.lq_type)) {
2413                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2414                                 ant_toggle_cnt++;
2415                         else if (priv &&
2416                                  rs_toggle_antenna(valid_tx_ant,
2417                                                    &new_rate, &tbl_type))
2418                                 ant_toggle_cnt = 1;
2419
2420                         repeat_rate = IWL_NUMBER_TRY;
2421                 } else {
2422                         repeat_rate = IWL_HT_NUMBER_TRY;
2423                 }
2424
2425                 /* Don't allow HT rates after next pass.
2426                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2427                 use_ht_possible = 0;
2428
2429                 /* Override next rate if needed for debug purposes */
2430                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2431
2432                 /* Fill next table entry */
2433                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2434
2435                 index++;
2436                 repeat_rate--;
2437         }
2438
2439         lq_cmd->agg_params.agg_frame_cnt_limit = 64;
2440         lq_cmd->agg_params.agg_dis_start_th = 3;
2441         lq_cmd->agg_params.agg_time_limit = cpu_to_le16(4000);
2442 }
2443
2444 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2445 {
2446         return hw->priv;
2447 }
2448 /* rate scale requires free function to be implemented */
2449 static void rs_free(void *priv_rate)
2450 {
2451         return;
2452 }
2453
2454 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2455                         void *priv_sta)
2456 {
2457         struct iwl_lq_sta *lq_sta = priv_sta;
2458         struct iwl_priv *priv __maybe_unused = priv_r;
2459
2460         IWL_DEBUG_RATE(priv, "enter\n");
2461         kfree(lq_sta);
2462         IWL_DEBUG_RATE(priv, "leave\n");
2463 }
2464
2465
2466 #ifdef CONFIG_MAC80211_DEBUGFS
2467 static int open_file_generic(struct inode *inode, struct file *file)
2468 {
2469         file->private_data = inode->i_private;
2470         return 0;
2471 }
2472 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2473                              u32 *rate_n_flags, int index)
2474 {
2475         struct iwl_priv *priv;
2476         u8 valid_tx_ant;
2477         u8 ant_sel_tx;
2478
2479         priv = lq_sta->drv;
2480         valid_tx_ant = priv->hw_params.valid_tx_ant;
2481         if (lq_sta->dbg_fixed_rate) {
2482                 ant_sel_tx =
2483                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2484                   >> RATE_MCS_ANT_POS);
2485                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2486                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2487                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2488                 } else {
2489                         lq_sta->dbg_fixed_rate = 0;
2490                         IWL_ERR(priv,
2491                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2492                             ant_sel_tx, valid_tx_ant);
2493                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2494                 }
2495         } else {
2496                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2497         }
2498 }
2499
2500 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2501                         const char __user *user_buf, size_t count, loff_t *ppos)
2502 {
2503         struct iwl_lq_sta *lq_sta = file->private_data;
2504         struct iwl_priv *priv;
2505         char buf[64];
2506         int buf_size;
2507         u32 parsed_rate;
2508
2509         priv = lq_sta->drv;
2510         memset(buf, 0, sizeof(buf));
2511         buf_size = min(count, sizeof(buf) -  1);
2512         if (copy_from_user(buf, user_buf, buf_size))
2513                 return -EFAULT;
2514
2515         if (sscanf(buf, "%x", &parsed_rate) == 1)
2516                 lq_sta->dbg_fixed_rate = parsed_rate;
2517         else
2518                 lq_sta->dbg_fixed_rate = 0;
2519
2520         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2521         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2522         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2523         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2524
2525         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2526                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2527
2528         if (lq_sta->dbg_fixed_rate) {
2529                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2530                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2531         }
2532
2533         return count;
2534 }
2535
2536 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2537                         char __user *user_buf, size_t count, loff_t *ppos)
2538 {
2539         char *buff;
2540         int desc = 0;
2541         int i = 0;
2542         ssize_t ret;
2543
2544         struct iwl_lq_sta *lq_sta = file->private_data;
2545         struct iwl_priv *priv;
2546         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2547
2548         priv = lq_sta->drv;
2549         buff = kmalloc(1024, GFP_KERNEL);
2550         if (!buff)
2551                 return -ENOMEM;
2552
2553         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2554         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2555                         lq_sta->total_failed, lq_sta->total_success,
2556                         lq_sta->active_legacy_rate);
2557         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2558                         lq_sta->dbg_fixed_rate);
2559         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2560             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2561             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2562             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2563         desc += sprintf(buff+desc, "lq type %s\n",
2564            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2565         if (is_Ht(tbl->lq_type)) {
2566                 desc += sprintf(buff+desc, " %s",
2567                    (is_siso(tbl->lq_type)) ? "SISO" :
2568                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2569                    desc += sprintf(buff+desc, " %s",
2570                    (tbl->is_fat) ? "40MHz" : "20MHz");
2571                 desc += sprintf(buff+desc, " %s\n", (tbl->is_SGI) ? "SGI" : "");
2572         }
2573         desc += sprintf(buff+desc, "general:"
2574                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2575                 lq_sta->lq.general_params.flags,
2576                 lq_sta->lq.general_params.mimo_delimiter,
2577                 lq_sta->lq.general_params.single_stream_ant_msk,
2578                 lq_sta->lq.general_params.dual_stream_ant_msk);
2579
2580         desc += sprintf(buff+desc, "agg:"
2581                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2582                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2583                         lq_sta->lq.agg_params.agg_dis_start_th,
2584                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2585
2586         desc += sprintf(buff+desc,
2587                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2588                         lq_sta->lq.general_params.start_rate_index[0],
2589                         lq_sta->lq.general_params.start_rate_index[1],
2590                         lq_sta->lq.general_params.start_rate_index[2],
2591                         lq_sta->lq.general_params.start_rate_index[3]);
2592
2593
2594         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2595                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2596                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2597
2598         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2599         kfree(buff);
2600         return ret;
2601 }
2602
2603 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2604         .write = rs_sta_dbgfs_scale_table_write,
2605         .read = rs_sta_dbgfs_scale_table_read,
2606         .open = open_file_generic,
2607 };
2608 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2609                         char __user *user_buf, size_t count, loff_t *ppos)
2610 {
2611         char *buff;
2612         int desc = 0;
2613         int i, j;
2614         ssize_t ret;
2615
2616         struct iwl_lq_sta *lq_sta = file->private_data;
2617
2618         buff = kmalloc(1024, GFP_KERNEL);
2619         if (!buff)
2620                 return -ENOMEM;
2621
2622         for (i = 0; i < LQ_SIZE; i++) {
2623                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2624                                 "rate=0x%X\n",
2625                                 lq_sta->active_tbl == i ? "*" : "x",
2626                                 lq_sta->lq_info[i].lq_type,
2627                                 lq_sta->lq_info[i].is_SGI,
2628                                 lq_sta->lq_info[i].is_fat,
2629                                 lq_sta->lq_info[i].is_dup,
2630                                 lq_sta->lq_info[i].current_rate);
2631                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2632                         desc += sprintf(buff+desc,
2633                                 "counter=%d success=%d %%=%d\n",
2634                                 lq_sta->lq_info[i].win[j].counter,
2635                                 lq_sta->lq_info[i].win[j].success_counter,
2636                                 lq_sta->lq_info[i].win[j].success_ratio);
2637                 }
2638         }
2639         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2640         kfree(buff);
2641         return ret;
2642 }
2643
2644 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2645         .read = rs_sta_dbgfs_stats_table_read,
2646         .open = open_file_generic,
2647 };
2648
2649 static void rs_add_debugfs(void *priv, void *priv_sta,
2650                                         struct dentry *dir)
2651 {
2652         struct iwl_lq_sta *lq_sta = priv_sta;
2653         lq_sta->rs_sta_dbgfs_scale_table_file =
2654                 debugfs_create_file("rate_scale_table", 0600, dir,
2655                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2656         lq_sta->rs_sta_dbgfs_stats_table_file =
2657                 debugfs_create_file("rate_stats_table", 0600, dir,
2658                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2659         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2660                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2661                 &lq_sta->tx_agg_tid_en);
2662
2663 }
2664
2665 static void rs_remove_debugfs(void *priv, void *priv_sta)
2666 {
2667         struct iwl_lq_sta *lq_sta = priv_sta;
2668         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2669         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2670         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2671 }
2672 #endif
2673
2674 static struct rate_control_ops rs_ops = {
2675         .module = NULL,
2676         .name = RS_NAME,
2677         .tx_status = rs_tx_status,
2678         .get_rate = rs_get_rate,
2679         .rate_init = rs_rate_init,
2680         .alloc = rs_alloc,
2681         .free = rs_free,
2682         .alloc_sta = rs_alloc_sta,
2683         .free_sta = rs_free_sta,
2684 #ifdef CONFIG_MAC80211_DEBUGFS
2685         .add_sta_debugfs = rs_add_debugfs,
2686         .remove_sta_debugfs = rs_remove_debugfs,
2687 #endif
2688 };
2689
2690 int iwlagn_rate_control_register(void)
2691 {
2692         return ieee80211_rate_control_register(&rs_ops);
2693 }
2694
2695 void iwlagn_rate_control_unregister(void)
2696 {
2697         ieee80211_rate_control_unregister(&rs_ops);
2698 }
2699