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

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2005 - 2009 Intel Corporation. All rights reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of version 2 of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  17  *
  18  * The full GNU General Public License is included in this distribution in the
  19  * file called LICENSE.
  20  *
  21  * Contact Information:
  22  *  Intel Linux Wireless <ilw@linux.intel.com>
  23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  24  *
  25  *****************************************************************************/
  26 #include <linux/kernel.h>
  27 #include <linux/init.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/wireless.h>
  30 #include <net/mac80211.h>
  31
  32 #include <linux/netdevice.h>
  33 #include <linux/etherdevice.h>
  34 #include <linux/delay.h>
  35
  36 #include <linux/workqueue.h>
  37
  38 #include "iwl-dev.h"
  39 #include "iwl-sta.h"
  40 #include "iwl-core.h"
  41
  42 #define RS_NAME "iwl-agn-rs"
  43
  44 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
  45 #define IWL_NUMBER_TRY      1
  46 #define IWL_HT_NUMBER_TRY   3
  47
  48 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
  49 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
  50 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
  51
  52 /* max allowed rate miss before sync LQ cmd */
  53 #define IWL_MISSED_RATE_MAX             15
  54 /* max time to accum history 2 seconds */
  55 #define IWL_RATE_SCALE_FLUSH_INTVL   (3*HZ)
  56
  57 static u8 rs_ht_to_legacy[] = {
  58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  60         IWL_RATE_6M_INDEX,
  61         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
  62         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
  63         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
  64         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
  65 };
  66
  67 static const u8 ant_toggle_lookup[] = {
  68         /*ANT_NONE -> */ ANT_NONE,
  69         /*ANT_A    -> */ ANT_B,
  70         /*ANT_B    -> */ ANT_C,
  71         /*ANT_AB   -> */ ANT_BC,
  72         /*ANT_C    -> */ ANT_A,
  73         /*ANT_AC   -> */ ANT_AB,
  74         /*ANT_BC   -> */ ANT_AC,
  75         /*ANT_ABC  -> */ ANT_ABC,
  76 };
  77
  78 /**
  79  * struct iwl_rate_scale_data -- tx success history for one rate
  80  */
  81 struct iwl_rate_scale_data {
  82         u64 data;               /* bitmap of successful frames */
  83         s32 success_counter;    /* number of frames successful */
  84         s32 success_ratio;      /* per-cent * 128  */
  85         s32 counter;            /* number of frames attempted */
  86         s32 average_tpt;        /* success ratio * expected throughput */
  87         unsigned long stamp;
  88 };
  89
  90 /**
  91  * struct iwl_scale_tbl_info -- tx params and success history for all rates
  92  *
  93  * There are two of these in struct iwl_lq_sta,
  94  * one for "active", and one for "search".
  95  */
  96 struct iwl_scale_tbl_info {
  97         enum iwl_table_type lq_type;
  98         u8 ant_type;
  99         u8 is_SGI;      /* 1 = short guard interval */
 100         u8 is_ht40;     /* 1 = 40 MHz channel width */
 101         u8 is_dup;      /* 1 = duplicated data streams */
 102         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
 103         u8 max_search;  /* maximun number of tables we can search */
 104         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
 105         u32 current_rate;  /* rate_n_flags, uCode API format */
 106         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
 107 };
 108
 109 struct iwl_traffic_load {
 110         unsigned long time_stamp;       /* age of the oldest statistics */
 111         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
 112                                                  * slice */
 113         u32 total;                      /* total num of packets during the
 114                                          * last TID_MAX_TIME_DIFF */
 115         u8 queue_count;                 /* number of queues that has
 116                                          * been used since the last cleanup */
 117         u8 head;                        /* start of the circular buffer */
 118 };
 119
 120 /**
 121  * struct iwl_lq_sta -- driver's rate scaling private structure
 122  *
 123  * Pointer to this gets passed back and forth between driver and mac80211.
 124  */
 125 struct iwl_lq_sta {
 126         u8 active_tbl;          /* index of active table, range 0-1 */
 127         u8 enable_counter;      /* indicates HT mode */
 128         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
 129         u8 search_better_tbl;   /* 1: currently trying alternate mode */
 130         s32 last_tpt;
 131
 132         /* The following determine when to search for a new mode */
 133         u32 table_count_limit;
 134         u32 max_failure_limit;  /* # failed frames before new search */
 135         u32 max_success_limit;  /* # successful frames before new search */
 136         u32 table_count;
 137         u32 total_failed;       /* total failed frames, any/all rates */
 138         u32 total_success;      /* total successful frames, any/all rates */
 139         u64 flush_timer;        /* time staying in mode before new search */
 140
 141         u8 action_counter;      /* # mode-switch actions tried */
 142         u8 is_green;
 143         u8 is_dup;
 144         enum ieee80211_band band;
 145         u8 ibss_sta_added;
 146
 147         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
 148         u32 supp_rates;
 149         u16 active_legacy_rate;
 150         u16 active_siso_rate;
 151         u16 active_mimo2_rate;
 152         u16 active_mimo3_rate;
 153         u16 active_rate_basic;
 154         s8 max_rate_idx;     /* Max rate set by user */
 155         u8 missed_rate_counter;
 156
 157         struct iwl_link_quality_cmd lq;
 158         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
 159         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
 160         u8 tx_agg_tid_en;
 161 #ifdef CONFIG_MAC80211_DEBUGFS
 162         struct dentry *rs_sta_dbgfs_scale_table_file;
 163         struct dentry *rs_sta_dbgfs_stats_table_file;
 164         struct dentry *rs_sta_dbgfs_rate_scale_data_file;
 165         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
 166         u32 dbg_fixed_rate;
 167 #endif
 168         struct iwl_priv *drv;
 169
 170         /* used to be in sta_info */
 171         int last_txrate_idx;
 172         /* last tx rate_n_flags */
 173         u32 last_rate_n_flags;
 174 };
 175
 176 static void rs_rate_scale_perform(struct iwl_priv *priv,
 177                                    struct sk_buff *skb,
 178                                    struct ieee80211_sta *sta,
 179                                    struct iwl_lq_sta *lq_sta);
 180 static void rs_fill_link_cmd(struct iwl_priv *priv,
 181                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
 182
 183
 184 #ifdef CONFIG_MAC80211_DEBUGFS
 185 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 186                              u32 *rate_n_flags, int index);
 187 #else
 188 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
 189                              u32 *rate_n_flags, int index)
 190 {}
 191 #endif
 192
 193 /*
 194  * Expected throughput metrics for following rates:
 195  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
 196  * "G" is the only table that supports CCK (the first 4 rates).
 197  */
 198
 199 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
 200         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
 201 };
 202
 203 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
 204         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
 205 };
 206
 207 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
 208         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
 209 };
 210
 211 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
 212         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
 213 };
 214
 215 static s32 expected_tpt_mimo2_20MHz[IWL_RATE_COUNT] = {
 216         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
 217 };
 218
 219 static s32 expected_tpt_mimo2_20MHzSGI[IWL_RATE_COUNT] = {
 220         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
 221 };
 222
 223 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
 224         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
 225 };
 226
 227 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
 228         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
 229 };
 230
 231 static s32 expected_tpt_mimo2_40MHz[IWL_RATE_COUNT] = {
 232         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
 233 };
 234
 235 static s32 expected_tpt_mimo2_40MHzSGI[IWL_RATE_COUNT] = {
 236         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
 237 };
 238
 239 /* Expected throughput metric MIMO3 */
 240 static s32 expected_tpt_mimo3_20MHz[IWL_RATE_COUNT] = {
 241         0, 0, 0, 0, 99, 99, 153, 186, 208, 239, 256, 263, 268
 242 };
 243
 244 static s32 expected_tpt_mimo3_20MHzSGI[IWL_RATE_COUNT] = {
 245         0, 0, 0, 0, 106, 106, 162, 194, 215, 246, 262, 268, 273
 246 };
 247
 248 static s32 expected_tpt_mimo3_40MHz[IWL_RATE_COUNT] = {
 249         0, 0, 0, 0, 152, 152, 211, 239, 255, 279, 290, 294, 297
 250 };
 251
 252 static s32 expected_tpt_mimo3_40MHzSGI[IWL_RATE_COUNT] = {
 253         0, 0, 0, 0, 160, 160, 219, 245, 261, 284, 294, 297, 300
 254 };
 255
 256 /* mbps, mcs */
 257 const static struct iwl_rate_mcs_info iwl_rate_mcs[IWL_RATE_COUNT] = {
 258   {"1", ""},
 259   {"2", ""},
 260   {"5.5", ""},
 261   {"11", ""},
 262   {"6", "BPSK 1/2"},
 263   {"9", "BPSK 1/2"},
 264   {"12", "QPSK 1/2"},
 265   {"18", "QPSK 3/4"},
 266   {"24", "16QAM 1/2"},
 267   {"36", "16QAM 3/4"},
 268   {"48", "64QAM 2/3"},
 269   {"54", "64QAM 3/4"},
 270   {"60", "64QAM 5/6"}
 271 };
 272
 273 #define MCS_INDEX_PER_STREAM    (8)
 274
 275 static inline u8 rs_extract_rate(u32 rate_n_flags)
 276 {
 277         return (u8)(rate_n_flags & 0xFF);
 278 }
 279
 280 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
 281 {
 282         window->data = 0;
 283         window->success_counter = 0;
 284         window->success_ratio = IWL_INVALID_VALUE;
 285         window->counter = 0;
 286         window->average_tpt = IWL_INVALID_VALUE;
 287         window->stamp = 0;
 288 }
 289
 290 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
 291 {
 292         return (ant_type & valid_antenna) == ant_type;
 293 }
 294
 295 /*
 296  *      removes the old data from the statistics. All data that is older than
 297  *      TID_MAX_TIME_DIFF, will be deleted.
 298  */
 299 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
 300 {
 301         /* The oldest age we want to keep */
 302         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
 303
 304         while (tl->queue_count &&
 305                (tl->time_stamp < oldest_time)) {
 306                 tl->total -= tl->packet_count[tl->head];
 307                 tl->packet_count[tl->head] = 0;
 308                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
 309                 tl->queue_count--;
 310                 tl->head++;
 311                 if (tl->head >= TID_QUEUE_MAX_SIZE)
 312                         tl->head = 0;
 313         }
 314 }
 315
 316 /*
 317  *      increment traffic load value for tid and also remove
 318  *      any old values if passed the certain time period
 319  */
 320 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
 321                            struct ieee80211_hdr *hdr)
 322 {
 323         u32 curr_time = jiffies_to_msecs(jiffies);
 324         u32 time_diff;
 325         s32 index;
 326         struct iwl_traffic_load *tl = NULL;
 327         u8 tid;
 328
 329         if (ieee80211_is_data_qos(hdr->frame_control)) {
 330                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 331                 tid = qc[0] & 0xf;
 332         } else
 333                 return MAX_TID_COUNT;
 334
 335         if (unlikely(tid >= TID_MAX_LOAD_COUNT))
 336                 return MAX_TID_COUNT;
 337
 338         tl = &lq_data->load[tid];
 339
 340         curr_time -= curr_time % TID_ROUND_VALUE;
 341
 342         /* Happens only for the first packet. Initialize the data */
 343         if (!(tl->queue_count)) {
 344                 tl->total = 1;
 345                 tl->time_stamp = curr_time;
 346                 tl->queue_count = 1;
 347                 tl->head = 0;
 348                 tl->packet_count[0] = 1;
 349                 return MAX_TID_COUNT;
 350         }
 351
 352         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 353         index = time_diff / TID_QUEUE_CELL_SPACING;
 354
 355         /* The history is too long: remove data that is older than */
 356         /* TID_MAX_TIME_DIFF */
 357         if (index >= TID_QUEUE_MAX_SIZE)
 358                 rs_tl_rm_old_stats(tl, curr_time);
 359
 360         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
 361         tl->packet_count[index] = tl->packet_count[index] + 1;
 362         tl->total = tl->total + 1;
 363
 364         if ((index + 1) > tl->queue_count)
 365                 tl->queue_count = index + 1;
 366
 367         return tid;
 368 }
 369
 370 /*
 371         get the traffic load value for tid
 372 */
 373 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
 374 {
 375         u32 curr_time = jiffies_to_msecs(jiffies);
 376         u32 time_diff;
 377         s32 index;
 378         struct iwl_traffic_load *tl = NULL;
 379
 380         if (tid >= TID_MAX_LOAD_COUNT)
 381                 return 0;
 382
 383         tl = &(lq_data->load[tid]);
 384
 385         curr_time -= curr_time % TID_ROUND_VALUE;
 386
 387         if (!(tl->queue_count))
 388                 return 0;
 389
 390         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
 391         index = time_diff / TID_QUEUE_CELL_SPACING;
 392
 393         /* The history is too long: remove data that is older than */
 394         /* TID_MAX_TIME_DIFF */
 395         if (index >= TID_QUEUE_MAX_SIZE)
 396                 rs_tl_rm_old_stats(tl, curr_time);
 397
 398         return tl->total;
 399 }
 400
 401 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
 402                                       struct iwl_lq_sta *lq_data, u8 tid,
 403                                       struct ieee80211_sta *sta)
 404 {
 405         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
 406                 IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n",
 407                                 sta->addr, tid);
 408                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
 409         }
 410 }
 411
 412 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
 413                               struct iwl_lq_sta *lq_data,
 414                               struct ieee80211_sta *sta)
 415 {
 416         if ((tid < TID_MAX_LOAD_COUNT))
 417                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 418         else if (tid == IWL_AGG_ALL_TID)
 419                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
 420                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
 421 }
 422
 423 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
 424 {
 425         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
 426                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
 427                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
 428 }
 429
 430 /**
 431  * rs_collect_tx_data - Update the success/failure sliding window
 432  *
 433  * We keep a sliding window of the last 62 packets transmitted
 434  * at this rate.  window->data contains the bitmask of successful
 435  * packets.
 436  */
 437 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
 438                               int scale_index, s32 tpt, int retries,
 439                               int successes)
 440 {
 441         struct iwl_rate_scale_data *window = NULL;
 442         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
 443         s32 fail_count;
 444
 445         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 446                 return -EINVAL;
 447
 448         /* Select data for current tx bit rate */
 449         window = &(windows[scale_index]);
 450
 451         /*
 452          * Keep track of only the latest 62 tx frame attempts in this rate's
 453          * history window; anything older isn't really relevant any more.
 454          * If we have filled up the sliding window, drop the oldest attempt;
 455          * if the oldest attempt (highest bit in bitmap) shows "success",
 456          * subtract "1" from the success counter (this is the main reason
 457          * we keep these bitmaps!).
 458          */
 459         while (retries > 0) {
 460                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
 461
 462                         /* remove earliest */
 463                         window->counter = IWL_RATE_MAX_WINDOW - 1;
 464
 465                         if (window->data & mask) {
 466                                 window->data &= ~mask;
 467                                 window->success_counter--;
 468                         }
 469                 }
 470
 471                 /* Increment frames-attempted counter */
 472                 window->counter++;
 473
 474                 /* Shift bitmap by one frame (throw away oldest history),
 475                  * OR in "1", and increment "success" if this
 476                  * frame was successful. */
 477                 window->data <<= 1;
 478                 if (successes > 0) {
 479                         window->success_counter++;
 480                         window->data |= 0x1;
 481                         successes--;
 482                 }
 483
 484                 retries--;
 485         }
 486
 487         /* Calculate current success ratio, avoid divide-by-0! */
 488         if (window->counter > 0)
 489                 window->success_ratio = 128 * (100 * window->success_counter)
 490                                         / window->counter;
 491         else
 492                 window->success_ratio = IWL_INVALID_VALUE;
 493
 494         fail_count = window->counter - window->success_counter;
 495
 496         /* Calculate average throughput, if we have enough history. */
 497         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 498             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 499                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 500         else
 501                 window->average_tpt = IWL_INVALID_VALUE;
 502
 503         /* Tag this window as having been updated */
 504         window->stamp = jiffies;
 505
 506         return 0;
 507 }
 508
 509 /*
 510  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 511  */
 512 /* FIXME:RS:remove this function and put the flags statically in the table */
 513 static u32 rate_n_flags_from_tbl(struct iwl_priv *priv,
 514                                  struct iwl_scale_tbl_info *tbl,
 515                                  int index, u8 use_green)
 516 {
 517         u32 rate_n_flags = 0;
 518
 519         if (is_legacy(tbl->lq_type)) {
 520                 rate_n_flags = iwl_rates[index].plcp;
 521                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 522                         rate_n_flags |= RATE_MCS_CCK_MSK;
 523
 524         } else if (is_Ht(tbl->lq_type)) {
 525                 if (index > IWL_LAST_OFDM_RATE) {
 526                         IWL_ERR(priv, "Invalid HT rate index %d\n", index);
 527                         index = IWL_LAST_OFDM_RATE;
 528                 }
 529                 rate_n_flags = RATE_MCS_HT_MSK;
 530
 531                 if (is_siso(tbl->lq_type))
 532                         rate_n_flags |= iwl_rates[index].plcp_siso;
 533                 else if (is_mimo2(tbl->lq_type))
 534                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
 535                 else
 536                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
 537         } else {
 538                 IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
 539         }
 540
 541         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
 542                                                      RATE_MCS_ANT_ABC_MSK);
 543
 544         if (is_Ht(tbl->lq_type)) {
 545                 if (tbl->is_ht40) {
 546                         if (tbl->is_dup)
 547                                 rate_n_flags |= RATE_MCS_DUP_MSK;
 548                         else
 549                                 rate_n_flags |= RATE_MCS_HT40_MSK;
 550                 }
 551                 if (tbl->is_SGI)
 552                         rate_n_flags |= RATE_MCS_SGI_MSK;
 553
 554                 if (use_green) {
 555                         rate_n_flags |= RATE_MCS_GF_MSK;
 556                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
 557                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
 558                                 IWL_ERR(priv, "GF was set with SGI:SISO\n");
 559                         }
 560                 }
 561         }
 562         return rate_n_flags;
 563 }
 564
 565 /*
 566  * Interpret uCode API's rate_n_flags format,
 567  * fill "search" or "active" tx mode table.
 568  */
 569 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
 570                                     enum ieee80211_band band,
 571                                     struct iwl_scale_tbl_info *tbl,
 572                                     int *rate_idx)
 573 {
 574         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
 575         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
 576         u8 mcs;
 577
 578         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 579
 580         if (*rate_idx  == IWL_RATE_INVALID) {
 581                 *rate_idx = -1;
 582                 return -EINVAL;
 583         }
 584         tbl->is_SGI = 0;        /* default legacy setup */
 585         tbl->is_ht40 = 0;
 586         tbl->is_dup = 0;
 587         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
 588         tbl->lq_type = LQ_NONE;
 589         tbl->max_search = IWL_MAX_SEARCH;
 590
 591         /* legacy rate format */
 592         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
 593                 if (num_of_ant == 1) {
 594                         if (band == IEEE80211_BAND_5GHZ)
 595                                 tbl->lq_type = LQ_A;
 596                         else
 597                                 tbl->lq_type = LQ_G;
 598                 }
 599         /* HT rate format */
 600         } else {
 601                 if (rate_n_flags & RATE_MCS_SGI_MSK)
 602                         tbl->is_SGI = 1;
 603
 604                 if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
 605                     (rate_n_flags & RATE_MCS_DUP_MSK))
 606                         tbl->is_ht40 = 1;
 607
 608                 if (rate_n_flags & RATE_MCS_DUP_MSK)
 609                         tbl->is_dup = 1;
 610
 611                 mcs = rs_extract_rate(rate_n_flags);
 612
 613                 /* SISO */
 614                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
 615                         if (num_of_ant == 1)
 616                                 tbl->lq_type = LQ_SISO; /*else NONE*/
 617                 /* MIMO2 */
 618                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
 619                         if (num_of_ant == 2)
 620                                 tbl->lq_type = LQ_MIMO2;
 621                 /* MIMO3 */
 622                 } else {
 623                         if (num_of_ant == 3) {
 624                                 tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
 625                                 tbl->lq_type = LQ_MIMO3;
 626                         }
 627                 }
 628         }
 629         return 0;
 630 }
 631
 632 /* switch to another antenna/antennas and return 1 */
 633 /* if no other valid antenna found, return 0 */
 634 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
 635                              struct iwl_scale_tbl_info *tbl)
 636 {
 637         u8 new_ant_type;
 638
 639         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
 640                 return 0;
 641
 642         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
 643                 return 0;
 644
 645         new_ant_type = ant_toggle_lookup[tbl->ant_type];
 646
 647         while ((new_ant_type != tbl->ant_type) &&
 648                !rs_is_valid_ant(valid_ant, new_ant_type))
 649                 new_ant_type = ant_toggle_lookup[new_ant_type];
 650
 651         if (new_ant_type == tbl->ant_type)
 652                 return 0;
 653
 654         tbl->ant_type = new_ant_type;
 655         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
 656         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
 657         return 1;
 658 }
 659
 660 /**
 661  * Green-field mode is valid if the station supports it and
 662  * there are no non-GF stations present in the BSS.
 663  */
 664 static inline u8 rs_use_green(struct ieee80211_sta *sta,
 665                               struct iwl_ht_info *ht_conf)
 666 {
 667         return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
 668                 !(ht_conf->non_GF_STA_present);
 669 }
 670
 671 /**
 672  * rs_get_supported_rates - get the available rates
 673  *
 674  * if management frame or broadcast frame only return
 675  * basic available rates.
 676  *
 677  */
 678 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
 679                                   struct ieee80211_hdr *hdr,
 680                                   enum iwl_table_type rate_type)
 681 {
 682         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 683             lq_sta->active_rate_basic)
 684                 return lq_sta->active_rate_basic;
 685
 686         if (is_legacy(rate_type)) {
 687                 return lq_sta->active_legacy_rate;
 688         } else {
 689                 if (is_siso(rate_type))
 690                         return lq_sta->active_siso_rate;
 691                 else if (is_mimo2(rate_type))
 692                         return lq_sta->active_mimo2_rate;
 693                 else
 694                         return lq_sta->active_mimo3_rate;
 695         }
 696 }
 697
 698 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
 699                                 int rate_type)
 700 {
 701         u8 high = IWL_RATE_INVALID;
 702         u8 low = IWL_RATE_INVALID;
 703
 704         /* 802.11A or ht walks to the next literal adjacent rate in
 705          * the rate table */
 706         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 707                 int i;
 708                 u32 mask;
 709
 710                 /* Find the previous rate that is in the rate mask */
 711                 i = index - 1;
 712                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 713                         if (rate_mask & mask) {
 714                                 low = i;
 715                                 break;
 716                         }
 717                 }
 718
 719                 /* Find the next rate that is in the rate mask */
 720                 i = index + 1;
 721                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 722                         if (rate_mask & mask) {
 723                                 high = i;
 724                                 break;
 725                         }
 726                 }
 727
 728                 return (high << 8) | low;
 729         }
 730
 731         low = index;
 732         while (low != IWL_RATE_INVALID) {
 733                 low = iwl_rates[low].prev_rs;
 734                 if (low == IWL_RATE_INVALID)
 735                         break;
 736                 if (rate_mask & (1 << low))
 737                         break;
 738                 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
 739         }
 740
 741         high = index;
 742         while (high != IWL_RATE_INVALID) {
 743                 high = iwl_rates[high].next_rs;
 744                 if (high == IWL_RATE_INVALID)
 745                         break;
 746                 if (rate_mask & (1 << high))
 747                         break;
 748                 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
 749         }
 750
 751         return (high << 8) | low;
 752 }
 753
 754 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
 755                              struct iwl_scale_tbl_info *tbl,
 756                              u8 scale_index, u8 ht_possible)
 757 {
 758         s32 low;
 759         u16 rate_mask;
 760         u16 high_low;
 761         u8 switch_to_legacy = 0;
 762         u8 is_green = lq_sta->is_green;
 763
 764         /* check if we need to switch from HT to legacy rates.
 765          * assumption is that mandatory rates (1Mbps or 6Mbps)
 766          * are always supported (spec demand) */
 767         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 768                 switch_to_legacy = 1;
 769                 scale_index = rs_ht_to_legacy[scale_index];
 770                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 771                         tbl->lq_type = LQ_A;
 772                 else
 773                         tbl->lq_type = LQ_G;
 774
 775                 if (num_of_ant(tbl->ant_type) > 1)
 776                         tbl->ant_type = ANT_A;/*FIXME:RS*/
 777
 778                 tbl->is_ht40 = 0;
 779                 tbl->is_SGI = 0;
 780                 tbl->max_search = IWL_MAX_SEARCH;
 781         }
 782
 783         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
 784
 785         /* Mask with station rate restriction */
 786         if (is_legacy(tbl->lq_type)) {
 787                 /* supp_rates has no CCK bits in A mode */
 788                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
 789                         rate_mask  = (u16)(rate_mask &
 790                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 791                 else
 792                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 793         }
 794
 795         /* If we switched from HT to legacy, check current rate */
 796         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 797                 low = scale_index;
 798                 goto out;
 799         }
 800
 801         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
 802                                         tbl->lq_type);
 803         low = high_low & 0xff;
 804
 805         if (low == IWL_RATE_INVALID)
 806                 low = scale_index;
 807
 808 out:
 809         return rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
 810 }
 811
 812 /*
 813  * mac80211 sends us Tx status
 814  */
 815 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
 816                          struct ieee80211_sta *sta, void *priv_sta,
 817                          struct sk_buff *skb)
 818 {
 819         int status;
 820         u8 retries;
 821         int rs_index, mac_index, index = 0;
 822         struct iwl_lq_sta *lq_sta = priv_sta;
 823         struct iwl_link_quality_cmd *table;
 824         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 825         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
 826         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 827         struct iwl_rate_scale_data *window = NULL;
 828         struct iwl_rate_scale_data *search_win = NULL;
 829         enum mac80211_rate_control_flags mac_flags;
 830         u32 tx_rate;
 831         struct iwl_scale_tbl_info tbl_type;
 832         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
 833         u8 active_index = 0;
 834         s32 tpt = 0;
 835
 836         IWL_DEBUG_RATE_LIMIT(priv, "get frame ack response, update rate scale window\n");
 837
 838         if (!ieee80211_is_data(hdr->frame_control) ||
 839             info->flags & IEEE80211_TX_CTL_NO_ACK)
 840                 return;
 841
 842         /* This packet was aggregated but doesn't carry rate scale info */
 843         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 844             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 845                 return;
 846
 847         if (info->flags & IEEE80211_TX_STAT_AMPDU)
 848                 retries = 0;
 849         else
 850                 retries = info->status.rates[0].count - 1;
 851
 852         if (retries > 15)
 853                 retries = 15;
 854
 855         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
 856             !lq_sta->ibss_sta_added)
 857                 goto out;
 858
 859         table = &lq_sta->lq;
 860         active_index = lq_sta->active_tbl;
 861
 862         curr_tbl = &(lq_sta->lq_info[active_index]);
 863         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
 864         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
 865         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
 866
 867         /*
 868          * Ignore this Tx frame response if its initial rate doesn't match
 869          * that of latest Link Quality command.  There may be stragglers
 870          * from a previous Link Quality command, but we're no longer interested
 871          * in those; they're either from the "active" mode while we're trying
 872          * to check "search" mode, or a prior "search" mode after we've moved
 873          * to a new "search" mode (which might become the new "active" mode).
 874          */
 875         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
 876         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 877         if (priv->band == IEEE80211_BAND_5GHZ)
 878                 rs_index -= IWL_FIRST_OFDM_RATE;
 879         mac_flags = info->status.rates[0].flags;
 880         mac_index = info->status.rates[0].idx;
 881         /* For HT packets, map MCS to PLCP */
 882         if (mac_flags & IEEE80211_TX_RC_MCS) {
 883                 mac_index &= RATE_MCS_CODE_MSK; /* Remove # of streams */
 884                 if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE))
 885                         mac_index++;
 886                 /*
 887                  * mac80211 HT index is always zero-indexed; we need to move
 888                  * HT OFDM rates after CCK rates in 2.4 GHz band
 889                  */
 890                 if (priv->band == IEEE80211_BAND_2GHZ)
 891                         mac_index += IWL_FIRST_OFDM_RATE;
 892         }
 893
 894         if ((mac_index < 0) ||
 895             (tbl_type.is_SGI != !!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) ||
 896             (tbl_type.is_ht40 != !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
 897             (tbl_type.is_dup != !!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) ||
 898             (tbl_type.ant_type != info->antenna_sel_tx) ||
 899             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(mac_flags & IEEE80211_TX_RC_MCS)) ||
 900             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
 901             (rs_index != mac_index)) {
 902                 IWL_DEBUG_RATE(priv, "initial rate %d does not match %d (0x%x)\n", mac_index, rs_index, tx_rate);
 903                 /* the last LQ command could failed so the LQ in ucode not
 904                  * the same in driver sync up
 905                  */
 906                 lq_sta->missed_rate_counter++;
 907                 if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
 908                         lq_sta->missed_rate_counter = 0;
 909                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
 910                 }
 911                 goto out;
 912         }
 913
 914         lq_sta->missed_rate_counter = 0;
 915         /* Update frame history window with "failure" for each Tx retry. */
 916         while (retries) {
 917                 /* Look up the rate and other info used for each tx attempt.
 918                  * Each tx attempt steps one entry deeper in the rate table. */
 919                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 920                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
 921                                           &tbl_type, &rs_index);
 922
 923                 /* If type matches "search" table,
 924                  * add failure to "search" history */
 925                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
 926                     (tbl_type.ant_type == search_tbl->ant_type) &&
 927                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
 928                         if (search_tbl->expected_tpt)
 929                                 tpt = search_tbl->expected_tpt[rs_index];
 930                         else
 931                                 tpt = 0;
 932                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
 933
 934                 /* Else if type matches "current/active" table,
 935                  * add failure to "current/active" history */
 936                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 937                            (tbl_type.ant_type == curr_tbl->ant_type) &&
 938                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 939                         if (curr_tbl->expected_tpt)
 940                                 tpt = curr_tbl->expected_tpt[rs_index];
 941                         else
 942                                 tpt = 0;
 943                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
 944                 }
 945
 946                 /* If not searching for a new mode, increment failed counter
 947                  * ... this helps determine when to start searching again */
 948                 if (lq_sta->stay_in_tbl)
 949                         lq_sta->total_failed++;
 950                 --retries;
 951                 index++;
 952
 953         }
 954
 955         /*
 956          * Find (by rate) the history window to update with final Tx attempt;
 957          * if Tx was successful first try, use original rate,
 958          * else look up the rate that was, finally, successful.
 959          */
 960         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
 961         lq_sta->last_rate_n_flags = tx_rate;
 962         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
 963
 964         /* Update frame history window with "success" if Tx got ACKed ... */
 965         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
 966
 967         /* If type matches "search" table,
 968          * add final tx status to "search" history */
 969         if ((tbl_type.lq_type == search_tbl->lq_type) &&
 970             (tbl_type.ant_type == search_tbl->ant_type) &&
 971             (tbl_type.is_SGI == search_tbl->is_SGI)) {
 972                 if (search_tbl->expected_tpt)
 973                         tpt = search_tbl->expected_tpt[rs_index];
 974                 else
 975                         tpt = 0;
 976                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 977                         rs_collect_tx_data(search_win, rs_index, tpt,
 978                                            info->status.ampdu_ack_len,
 979                                            info->status.ampdu_ack_map);
 980                 else
 981                         rs_collect_tx_data(search_win, rs_index, tpt,
 982                                            1, status);
 983         /* Else if type matches "current/active" table,
 984          * add final tx status to "current/active" history */
 985         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 986                    (tbl_type.ant_type == curr_tbl->ant_type) &&
 987                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 988                 if (curr_tbl->expected_tpt)
 989                         tpt = curr_tbl->expected_tpt[rs_index];
 990                 else
 991                         tpt = 0;
 992                 if (info->flags & IEEE80211_TX_STAT_AMPDU)
 993                         rs_collect_tx_data(window, rs_index, tpt,
 994                                            info->status.ampdu_ack_len,
 995                                            info->status.ampdu_ack_map);
 996                 else
 997                         rs_collect_tx_data(window, rs_index, tpt,
 998                                            1, status);
 999         }
1000
1001         /* If not searching for new mode, increment success/failed counter
1002          * ... these help determine when to start searching again */
1003         if (lq_sta->stay_in_tbl) {
1004                 if (info->flags & IEEE80211_TX_STAT_AMPDU) {
1005                         lq_sta->total_success += info->status.ampdu_ack_map;
1006                         lq_sta->total_failed +=
1007                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
1008                 } else {
1009                         if (status)
1010                                 lq_sta->total_success++;
1011                         else
1012                                 lq_sta->total_failed++;
1013                 }
1014         }
1015
1016         /* See if there's a better rate or modulation mode to try. */
1017         if (sta && sta->supp_rates[sband->band])
1018                 rs_rate_scale_perform(priv, skb, sta, lq_sta);
1019 out:
1020         return;
1021 }
1022
1023 /*
1024  * Begin a period of staying with a selected modulation mode.
1025  * Set "stay_in_tbl" flag to prevent any mode switches.
1026  * Set frame tx success limits according to legacy vs. high-throughput,
1027  * and reset overall (spanning all rates) tx success history statistics.
1028  * These control how long we stay using same modulation mode before
1029  * searching for a new mode.
1030  */
1031 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
1032                                  struct iwl_lq_sta *lq_sta)
1033 {
1034         IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
1035         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
1036         if (is_legacy) {
1037                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
1038                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
1039                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
1040         } else {
1041                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
1042                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
1043                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
1044         }
1045         lq_sta->table_count = 0;
1046         lq_sta->total_failed = 0;
1047         lq_sta->total_success = 0;
1048         lq_sta->flush_timer = jiffies;
1049         lq_sta->action_counter = 0;
1050 }
1051
1052 /*
1053  * Find correct throughput table for given mode of modulation
1054  */
1055 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
1056                                       struct iwl_scale_tbl_info *tbl)
1057 {
1058         if (is_legacy(tbl->lq_type)) {
1059                 if (!is_a_band(tbl->lq_type))
1060                         tbl->expected_tpt = expected_tpt_G;
1061                 else
1062                         tbl->expected_tpt = expected_tpt_A;
1063         } else if (is_siso(tbl->lq_type)) {
1064                 if (tbl->is_ht40 && !lq_sta->is_dup)
1065                         if (tbl->is_SGI)
1066                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
1067                         else
1068                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1069                 else if (tbl->is_SGI)
1070                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1071                 else
1072                         tbl->expected_tpt = expected_tpt_siso20MHz;
1073         } else if (is_mimo2(tbl->lq_type)) {
1074                 if (tbl->is_ht40 && !lq_sta->is_dup)
1075                         if (tbl->is_SGI)
1076                                 tbl->expected_tpt = expected_tpt_mimo2_40MHzSGI;
1077                         else
1078                                 tbl->expected_tpt = expected_tpt_mimo2_40MHz;
1079                 else if (tbl->is_SGI)
1080                         tbl->expected_tpt = expected_tpt_mimo2_20MHzSGI;
1081                 else
1082                         tbl->expected_tpt = expected_tpt_mimo2_20MHz;
1083         } else if (is_mimo3(tbl->lq_type)) {
1084                 if (tbl->is_ht40 && !lq_sta->is_dup)
1085                         if (tbl->is_SGI)
1086                                 tbl->expected_tpt = expected_tpt_mimo3_40MHzSGI;
1087                         else
1088                                 tbl->expected_tpt = expected_tpt_mimo3_40MHz;
1089                 else if (tbl->is_SGI)
1090                         tbl->expected_tpt = expected_tpt_mimo3_20MHzSGI;
1091                 else
1092                         tbl->expected_tpt = expected_tpt_mimo3_20MHz;
1093         } else
1094                 tbl->expected_tpt = expected_tpt_G;
1095 }
1096
1097 /*
1098  * Find starting rate for new "search" high-throughput mode of modulation.
1099  * Goal is to find lowest expected rate (under perfect conditions) that is
1100  * above the current measured throughput of "active" mode, to give new mode
1101  * a fair chance to prove itself without too many challenges.
1102  *
1103  * This gets called when transitioning to more aggressive modulation
1104  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1105  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1106  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1107  * bit rate will typically need to increase, but not if performance was bad.
1108  */
1109 static s32 rs_get_best_rate(struct iwl_priv *priv,
1110                             struct iwl_lq_sta *lq_sta,
1111                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1112                             u16 rate_mask, s8 index)
1113 {
1114         /* "active" values */
1115         struct iwl_scale_tbl_info *active_tbl =
1116             &(lq_sta->lq_info[lq_sta->active_tbl]);
1117         s32 active_sr = active_tbl->win[index].success_ratio;
1118         s32 active_tpt = active_tbl->expected_tpt[index];
1119
1120         /* expected "search" throughput */
1121         s32 *tpt_tbl = tbl->expected_tpt;
1122
1123         s32 new_rate, high, low, start_hi;
1124         u16 high_low;
1125         s8 rate = index;
1126
1127         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1128
1129         for (; ;) {
1130                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1131                                                 tbl->lq_type);
1132
1133                 low = high_low & 0xff;
1134                 high = (high_low >> 8) & 0xff;
1135
1136                 /*
1137                  * Lower the "search" bit rate, to give new "search" mode
1138                  * approximately the same throughput as "active" if:
1139                  *
1140                  * 1) "Active" mode has been working modestly well (but not
1141                  *    great), and expected "search" throughput (under perfect
1142                  *    conditions) at candidate rate is above the actual
1143                  *    measured "active" throughput (but less than expected
1144                  *    "active" throughput under perfect conditions).
1145                  * OR
1146                  * 2) "Active" mode has been working perfectly or very well
1147                  *    and expected "search" throughput (under perfect
1148                  *    conditions) at candidate rate is above expected
1149                  *    "active" throughput (under perfect conditions).
1150                  */
1151                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1152                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1153                       (active_sr <= IWL_RATE_HIGH_TH) &&
1154                       (tpt_tbl[rate] <= active_tpt))) ||
1155                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1156                      (tpt_tbl[rate] > active_tpt))) {
1157
1158                         /* (2nd or later pass)
1159                          * If we've already tried to raise the rate, and are
1160                          * now trying to lower it, use the higher rate. */
1161                         if (start_hi != IWL_RATE_INVALID) {
1162                                 new_rate = start_hi;
1163                                 break;
1164                         }
1165
1166                         new_rate = rate;
1167
1168                         /* Loop again with lower rate */
1169                         if (low != IWL_RATE_INVALID)
1170                                 rate = low;
1171
1172                         /* Lower rate not available, use the original */
1173                         else
1174                                 break;
1175
1176                 /* Else try to raise the "search" rate to match "active" */
1177                 } else {
1178                         /* (2nd or later pass)
1179                          * If we've already tried to lower the rate, and are
1180                          * now trying to raise it, use the lower rate. */
1181                         if (new_rate != IWL_RATE_INVALID)
1182                                 break;
1183
1184                         /* Loop again with higher rate */
1185                         else if (high != IWL_RATE_INVALID) {
1186                                 start_hi = high;
1187                                 rate = high;
1188
1189                         /* Higher rate not available, use the original */
1190                         } else {
1191                                 new_rate = rate;
1192                                 break;
1193                         }
1194                 }
1195         }
1196
1197         return new_rate;
1198 }
1199
1200 /*
1201  * Set up search table for MIMO2
1202  */
1203 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1204                              struct iwl_lq_sta *lq_sta,
1205                              struct ieee80211_conf *conf,
1206                              struct ieee80211_sta *sta,
1207                              struct iwl_scale_tbl_info *tbl, int index)
1208 {
1209         u16 rate_mask;
1210         s32 rate;
1211         s8 is_green = lq_sta->is_green;
1212
1213         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1214                 return -1;
1215
1216         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1217                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1218                 return -1;
1219
1220         /* Need both Tx chains/antennas to support MIMO */
1221         if (priv->hw_params.tx_chains_num < 2)
1222                 return -1;
1223
1224         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1225
1226         tbl->lq_type = LQ_MIMO2;
1227         tbl->is_dup = lq_sta->is_dup;
1228         tbl->action = 0;
1229         tbl->max_search = IWL_MAX_SEARCH;
1230         rate_mask = lq_sta->active_mimo2_rate;
1231
1232         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1233                 tbl->is_ht40 = 1;
1234         else
1235                 tbl->is_ht40 = 0;
1236
1237         rs_set_expected_tpt_table(lq_sta, tbl);
1238
1239         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1240
1241         IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1242         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1243                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1244                                                 rate, rate_mask);
1245                 return -1;
1246         }
1247         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1248
1249         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1250                      tbl->current_rate, is_green);
1251         return 0;
1252 }
1253
1254 /*
1255  * Set up search table for MIMO3
1256  */
1257 static int rs_switch_to_mimo3(struct iwl_priv *priv,
1258                              struct iwl_lq_sta *lq_sta,
1259                              struct ieee80211_conf *conf,
1260                              struct ieee80211_sta *sta,
1261                              struct iwl_scale_tbl_info *tbl, int index)
1262 {
1263         u16 rate_mask;
1264         s32 rate;
1265         s8 is_green = lq_sta->is_green;
1266
1267         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1268                 return -1;
1269
1270         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1271                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1272                 return -1;
1273
1274         /* Need both Tx chains/antennas to support MIMO */
1275         if (priv->hw_params.tx_chains_num < 3)
1276                 return -1;
1277
1278         IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO3\n");
1279
1280         tbl->lq_type = LQ_MIMO3;
1281         tbl->is_dup = lq_sta->is_dup;
1282         tbl->action = 0;
1283         tbl->max_search = IWL_MAX_11N_MIMO3_SEARCH;
1284         rate_mask = lq_sta->active_mimo3_rate;
1285
1286         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1287                 tbl->is_ht40 = 1;
1288         else
1289                 tbl->is_ht40 = 0;
1290
1291         rs_set_expected_tpt_table(lq_sta, tbl);
1292
1293         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1294
1295         IWL_DEBUG_RATE(priv, "LQ: MIMO3 best rate %d mask %X\n",
1296                 rate, rate_mask);
1297         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1298                 IWL_DEBUG_RATE(priv, "Can't switch with index %d rate mask %x\n",
1299                                                 rate, rate_mask);
1300                 return -1;
1301         }
1302         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1303
1304         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1305                      tbl->current_rate, is_green);
1306         return 0;
1307 }
1308
1309 /*
1310  * Set up search table for SISO
1311  */
1312 static int rs_switch_to_siso(struct iwl_priv *priv,
1313                              struct iwl_lq_sta *lq_sta,
1314                              struct ieee80211_conf *conf,
1315                              struct ieee80211_sta *sta,
1316                              struct iwl_scale_tbl_info *tbl, int index)
1317 {
1318         u16 rate_mask;
1319         u8 is_green = lq_sta->is_green;
1320         s32 rate;
1321
1322         if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1323                 return -1;
1324
1325         IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1326
1327         tbl->is_dup = lq_sta->is_dup;
1328         tbl->lq_type = LQ_SISO;
1329         tbl->action = 0;
1330         tbl->max_search = IWL_MAX_SEARCH;
1331         rate_mask = lq_sta->active_siso_rate;
1332
1333         if (iwl_is_ht40_tx_allowed(priv, &sta->ht_cap))
1334                 tbl->is_ht40 = 1;
1335         else
1336                 tbl->is_ht40 = 0;
1337
1338         if (is_green)
1339                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1340
1341         rs_set_expected_tpt_table(lq_sta, tbl);
1342         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1343
1344         IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1345         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1346                 IWL_DEBUG_RATE(priv, "can not switch with index %d rate mask %x\n",
1347                              rate, rate_mask);
1348                 return -1;
1349         }
1350         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, rate, is_green);
1351         IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1352                      tbl->current_rate, is_green);
1353         return 0;
1354 }
1355
1356 /*
1357  * Try to switch to new modulation mode from legacy
1358  */
1359 static int rs_move_legacy_other(struct iwl_priv *priv,
1360                                 struct iwl_lq_sta *lq_sta,
1361                                 struct ieee80211_conf *conf,
1362                                 struct ieee80211_sta *sta,
1363                                 int index)
1364 {
1365         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1366         struct iwl_scale_tbl_info *search_tbl =
1367                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1368         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1369         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1370                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1371         u8 start_action = tbl->action;
1372         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1373         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1374         int ret = 0;
1375         u8 update_search_tbl_counter = 0;
1376
1377         if (!iwl_ht_enabled(priv))
1378                 /* stay in Legacy */
1379                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1380         else if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1381                    tbl->action > IWL_LEGACY_SWITCH_SISO)
1382                 tbl->action = IWL_LEGACY_SWITCH_SISO;
1383         for (; ;) {
1384                 lq_sta->action_counter++;
1385                 switch (tbl->action) {
1386                 case IWL_LEGACY_SWITCH_ANTENNA1:
1387                 case IWL_LEGACY_SWITCH_ANTENNA2:
1388                         IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1389
1390                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1391                                                         tx_chains_num <= 1) ||
1392                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1393                                                         tx_chains_num <= 2))
1394                                 break;
1395
1396                         /* Don't change antenna if success has been great */
1397                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1398                                 break;
1399
1400                         /* Set up search table to try other antenna */
1401                         memcpy(search_tbl, tbl, sz);
1402
1403                         if (rs_toggle_antenna(valid_tx_ant,
1404                                 &search_tbl->current_rate, search_tbl)) {
1405                                 update_search_tbl_counter = 1;
1406                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1407                                 goto out;
1408                         }
1409                         break;
1410                 case IWL_LEGACY_SWITCH_SISO:
1411                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1412
1413                         /* Set up search table to try SISO */
1414                         memcpy(search_tbl, tbl, sz);
1415                         search_tbl->is_SGI = 0;
1416                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1417                                                  search_tbl, index);
1418                         if (!ret) {
1419                                 lq_sta->action_counter = 0;
1420                                 goto out;
1421                         }
1422
1423                         break;
1424                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1425                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1426                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1427                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1428
1429                         /* Set up search table to try MIMO */
1430                         memcpy(search_tbl, tbl, sz);
1431                         search_tbl->is_SGI = 0;
1432
1433                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1434                                 search_tbl->ant_type = ANT_AB;
1435                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1436                                 search_tbl->ant_type = ANT_AC;
1437                         else
1438                                 search_tbl->ant_type = ANT_BC;
1439
1440                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1441                                 break;
1442
1443                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1444                                                  search_tbl, index);
1445                         if (!ret) {
1446                                 lq_sta->action_counter = 0;
1447                                 goto out;
1448                         }
1449                         break;
1450
1451                 case IWL_LEGACY_SWITCH_MIMO3_ABC:
1452                         IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO3\n");
1453
1454                         /* Set up search table to try MIMO3 */
1455                         memcpy(search_tbl, tbl, sz);
1456                         search_tbl->is_SGI = 0;
1457
1458                         search_tbl->ant_type = ANT_ABC;
1459
1460                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1461                                 break;
1462
1463                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1464                                                  search_tbl, index);
1465                         if (!ret) {
1466                                 lq_sta->action_counter = 0;
1467                                 goto out;
1468                         }
1469                         break;
1470                 }
1471                 tbl->action++;
1472                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1473                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1474
1475                 if (tbl->action == start_action)
1476                         break;
1477
1478         }
1479         search_tbl->lq_type = LQ_NONE;
1480         return 0;
1481
1482 out:
1483         lq_sta->search_better_tbl = 1;
1484         tbl->action++;
1485         if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1486                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1487         if (update_search_tbl_counter)
1488                 search_tbl->action = tbl->action;
1489         return 0;
1490
1491 }
1492
1493 /*
1494  * Try to switch to new modulation mode from SISO
1495  */
1496 static int rs_move_siso_to_other(struct iwl_priv *priv,
1497                                  struct iwl_lq_sta *lq_sta,
1498                                  struct ieee80211_conf *conf,
1499                                  struct ieee80211_sta *sta, int index)
1500 {
1501         u8 is_green = lq_sta->is_green;
1502         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1503         struct iwl_scale_tbl_info *search_tbl =
1504                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1505         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1506         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1507         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1508                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1509         u8 start_action = tbl->action;
1510         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1511         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1512         u8 update_search_tbl_counter = 0;
1513         int ret;
1514
1515         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE &&
1516             tbl->action > IWL_SISO_SWITCH_ANTENNA2) {
1517                 /* stay in SISO */
1518                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1519         }
1520         for (;;) {
1521                 lq_sta->action_counter++;
1522                 switch (tbl->action) {
1523                 case IWL_SISO_SWITCH_ANTENNA1:
1524                 case IWL_SISO_SWITCH_ANTENNA2:
1525                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1526
1527                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1528                                                         tx_chains_num <= 1) ||
1529                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1530                                                         tx_chains_num <= 2))
1531                                 break;
1532
1533                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1534                                 break;
1535
1536                         memcpy(search_tbl, tbl, sz);
1537                         if (rs_toggle_antenna(valid_tx_ant,
1538                                        &search_tbl->current_rate, search_tbl)) {
1539                                 update_search_tbl_counter = 1;
1540                                 goto out;
1541                         }
1542                         break;
1543                 case IWL_SISO_SWITCH_MIMO2_AB:
1544                 case IWL_SISO_SWITCH_MIMO2_AC:
1545                 case IWL_SISO_SWITCH_MIMO2_BC:
1546                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1547                         memcpy(search_tbl, tbl, sz);
1548                         search_tbl->is_SGI = 0;
1549
1550                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1551                                 search_tbl->ant_type = ANT_AB;
1552                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1553                                 search_tbl->ant_type = ANT_AC;
1554                         else
1555                                 search_tbl->ant_type = ANT_BC;
1556
1557                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1558                                 break;
1559
1560                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1561                                                  search_tbl, index);
1562                         if (!ret)
1563                                 goto out;
1564                         break;
1565                 case IWL_SISO_SWITCH_GI:
1566                         if (!tbl->is_ht40 && !(ht_cap->cap &
1567                                                 IEEE80211_HT_CAP_SGI_20))
1568                                 break;
1569                         if (tbl->is_ht40 && !(ht_cap->cap &
1570                                                 IEEE80211_HT_CAP_SGI_40))
1571                                 break;
1572
1573                         IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1574
1575                         memcpy(search_tbl, tbl, sz);
1576                         if (is_green) {
1577                                 if (!tbl->is_SGI)
1578                                         break;
1579                                 else
1580                                         IWL_ERR(priv,
1581                                                 "SGI was set in GF+SISO\n");
1582                         }
1583                         search_tbl->is_SGI = !tbl->is_SGI;
1584                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1585                         if (tbl->is_SGI) {
1586                                 s32 tpt = lq_sta->last_tpt / 100;
1587                                 if (tpt >= search_tbl->expected_tpt[index])
1588                                         break;
1589                         }
1590                         search_tbl->current_rate =
1591                                 rate_n_flags_from_tbl(priv, search_tbl,
1592                                                       index, is_green);
1593                         update_search_tbl_counter = 1;
1594                         goto out;
1595                 case IWL_SISO_SWITCH_MIMO3_ABC:
1596                         IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO3\n");
1597                         memcpy(search_tbl, tbl, sz);
1598                         search_tbl->is_SGI = 0;
1599                         search_tbl->ant_type = ANT_ABC;
1600
1601                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1602                                 break;
1603
1604                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1605                                                  search_tbl, index);
1606                         if (!ret)
1607                                 goto out;
1608                         break;
1609                 }
1610                 tbl->action++;
1611                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO3_ABC)
1612                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1613
1614                 if (tbl->action == start_action)
1615                         break;
1616         }
1617         search_tbl->lq_type = LQ_NONE;
1618         return 0;
1619
1620  out:
1621         lq_sta->search_better_tbl = 1;
1622         tbl->action++;
1623         if (tbl->action > IWL_SISO_SWITCH_MIMO3_ABC)
1624                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1625         if (update_search_tbl_counter)
1626                 search_tbl->action = tbl->action;
1627
1628         return 0;
1629 }
1630
1631 /*
1632  * Try to switch to new modulation mode from MIMO2
1633  */
1634 static int rs_move_mimo2_to_other(struct iwl_priv *priv,
1635                                  struct iwl_lq_sta *lq_sta,
1636                                  struct ieee80211_conf *conf,
1637                                  struct ieee80211_sta *sta, int index)
1638 {
1639         s8 is_green = lq_sta->is_green;
1640         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1641         struct iwl_scale_tbl_info *search_tbl =
1642                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1643         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1644         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1645         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1646                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1647         u8 start_action = tbl->action;
1648         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1649         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1650         u8 update_search_tbl_counter = 0;
1651         int ret;
1652
1653         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1654             (tbl->action < IWL_MIMO2_SWITCH_SISO_A ||
1655              tbl->action > IWL_MIMO2_SWITCH_SISO_C)) {
1656                 /* switch in SISO */
1657                 tbl->action = IWL_MIMO2_SWITCH_SISO_A;
1658         }
1659         for (;;) {
1660                 lq_sta->action_counter++;
1661                 switch (tbl->action) {
1662                 case IWL_MIMO2_SWITCH_ANTENNA1:
1663                 case IWL_MIMO2_SWITCH_ANTENNA2:
1664                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1665
1666                         if (tx_chains_num <= 2)
1667                                 break;
1668
1669                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1670                                 break;
1671
1672                         memcpy(search_tbl, tbl, sz);
1673                         if (rs_toggle_antenna(valid_tx_ant,
1674                                        &search_tbl->current_rate, search_tbl)) {
1675                                 update_search_tbl_counter = 1;
1676                                 goto out;
1677                         }
1678                         break;
1679                 case IWL_MIMO2_SWITCH_SISO_A:
1680                 case IWL_MIMO2_SWITCH_SISO_B:
1681                 case IWL_MIMO2_SWITCH_SISO_C:
1682                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1683
1684                         /* Set up new search table for SISO */
1685                         memcpy(search_tbl, tbl, sz);
1686
1687                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1688                                 search_tbl->ant_type = ANT_A;
1689                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1690                                 search_tbl->ant_type = ANT_B;
1691                         else
1692                                 search_tbl->ant_type = ANT_C;
1693
1694                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1695                                 break;
1696
1697                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1698                                                  search_tbl, index);
1699                         if (!ret)
1700                                 goto out;
1701
1702                         break;
1703
1704                 case IWL_MIMO2_SWITCH_GI:
1705                         if (!tbl->is_ht40 && !(ht_cap->cap &
1706                                                 IEEE80211_HT_CAP_SGI_20))
1707                                 break;
1708                         if (tbl->is_ht40 && !(ht_cap->cap &
1709                                                 IEEE80211_HT_CAP_SGI_40))
1710                                 break;
1711
1712                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1713
1714                         /* Set up new search table for MIMO2 */
1715                         memcpy(search_tbl, tbl, sz);
1716                         search_tbl->is_SGI = !tbl->is_SGI;
1717                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1718                         /*
1719                          * If active table already uses the fastest possible
1720                          * modulation (dual stream with short guard interval),
1721                          * and it's working well, there's no need to look
1722                          * for a better type of modulation!
1723                          */
1724                         if (tbl->is_SGI) {
1725                                 s32 tpt = lq_sta->last_tpt / 100;
1726                                 if (tpt >= search_tbl->expected_tpt[index])
1727                                         break;
1728                         }
1729                         search_tbl->current_rate =
1730                                 rate_n_flags_from_tbl(priv, search_tbl,
1731                                                       index, is_green);
1732                         update_search_tbl_counter = 1;
1733                         goto out;
1734
1735                 case IWL_MIMO2_SWITCH_MIMO3_ABC:
1736                         IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to MIMO3\n");
1737                         memcpy(search_tbl, tbl, sz);
1738                         search_tbl->is_SGI = 0;
1739                         search_tbl->ant_type = ANT_ABC;
1740
1741                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1742                                 break;
1743
1744                         ret = rs_switch_to_mimo3(priv, lq_sta, conf, sta,
1745                                                  search_tbl, index);
1746                         if (!ret)
1747                                 goto out;
1748
1749                         break;
1750                 }
1751                 tbl->action++;
1752                 if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1753                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1754
1755                 if (tbl->action == start_action)
1756                         break;
1757         }
1758         search_tbl->lq_type = LQ_NONE;
1759         return 0;
1760  out:
1761         lq_sta->search_better_tbl = 1;
1762         tbl->action++;
1763         if (tbl->action > IWL_MIMO2_SWITCH_MIMO3_ABC)
1764                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1765         if (update_search_tbl_counter)
1766                 search_tbl->action = tbl->action;
1767
1768         return 0;
1769
1770 }
1771
1772 /*
1773  * Try to switch to new modulation mode from MIMO3
1774  */
1775 static int rs_move_mimo3_to_other(struct iwl_priv *priv,
1776                                  struct iwl_lq_sta *lq_sta,
1777                                  struct ieee80211_conf *conf,
1778                                  struct ieee80211_sta *sta, int index)
1779 {
1780         s8 is_green = lq_sta->is_green;
1781         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1782         struct iwl_scale_tbl_info *search_tbl =
1783                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1784         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1785         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1786         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1787                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1788         u8 start_action = tbl->action;
1789         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1790         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1791         int ret;
1792         u8 update_search_tbl_counter = 0;
1793
1794         if ((iwl_tx_ant_restriction(priv) == IWL_ANT_OK_SINGLE) &&
1795             (tbl->action < IWL_MIMO3_SWITCH_SISO_A ||
1796              tbl->action > IWL_MIMO3_SWITCH_SISO_C)) {
1797                 /* switch in SISO */
1798                 tbl->action = IWL_MIMO3_SWITCH_SISO_A;
1799         }
1800         for (;;) {
1801                 lq_sta->action_counter++;
1802                 switch (tbl->action) {
1803                 case IWL_MIMO3_SWITCH_ANTENNA1:
1804                 case IWL_MIMO3_SWITCH_ANTENNA2:
1805                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle Antennas\n");
1806
1807                         if (tx_chains_num <= 3)
1808                                 break;
1809
1810                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1811                                 break;
1812
1813                         memcpy(search_tbl, tbl, sz);
1814                         if (rs_toggle_antenna(valid_tx_ant,
1815                                        &search_tbl->current_rate, search_tbl))
1816                                 goto out;
1817                         break;
1818                 case IWL_MIMO3_SWITCH_SISO_A:
1819                 case IWL_MIMO3_SWITCH_SISO_B:
1820                 case IWL_MIMO3_SWITCH_SISO_C:
1821                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to SISO\n");
1822
1823                         /* Set up new search table for SISO */
1824                         memcpy(search_tbl, tbl, sz);
1825
1826                         if (tbl->action == IWL_MIMO3_SWITCH_SISO_A)
1827                                 search_tbl->ant_type = ANT_A;
1828                         else if (tbl->action == IWL_MIMO3_SWITCH_SISO_B)
1829                                 search_tbl->ant_type = ANT_B;
1830                         else
1831                                 search_tbl->ant_type = ANT_C;
1832
1833                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1834                                 break;
1835
1836                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1837                                                  search_tbl, index);
1838                         if (!ret)
1839                                 goto out;
1840
1841                         break;
1842
1843                 case IWL_MIMO3_SWITCH_MIMO2_AB:
1844                 case IWL_MIMO3_SWITCH_MIMO2_AC:
1845                 case IWL_MIMO3_SWITCH_MIMO2_BC:
1846                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 switch to MIMO2\n");
1847
1848                         memcpy(search_tbl, tbl, sz);
1849                         search_tbl->is_SGI = 0;
1850                         if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AB)
1851                                 search_tbl->ant_type = ANT_AB;
1852                         else if (tbl->action == IWL_MIMO3_SWITCH_MIMO2_AC)
1853                                 search_tbl->ant_type = ANT_AC;
1854                         else
1855                                 search_tbl->ant_type = ANT_BC;
1856
1857                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1858                                 break;
1859
1860                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1861                                                  search_tbl, index);
1862                         if (!ret)
1863                                 goto out;
1864
1865                         break;
1866
1867                 case IWL_MIMO3_SWITCH_GI:
1868                         if (!tbl->is_ht40 && !(ht_cap->cap &
1869                                                 IEEE80211_HT_CAP_SGI_20))
1870                                 break;
1871                         if (tbl->is_ht40 && !(ht_cap->cap &
1872                                                 IEEE80211_HT_CAP_SGI_40))
1873                                 break;
1874
1875                         IWL_DEBUG_RATE(priv, "LQ: MIMO3 toggle SGI/NGI\n");
1876
1877                         /* Set up new search table for MIMO */
1878                         memcpy(search_tbl, tbl, sz);
1879                         search_tbl->is_SGI = !tbl->is_SGI;
1880                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1881                         /*
1882                          * If active table already uses the fastest possible
1883                          * modulation (dual stream with short guard interval),
1884                          * and it's working well, there's no need to look
1885                          * for a better type of modulation!
1886                          */
1887                         if (tbl->is_SGI) {
1888                                 s32 tpt = lq_sta->last_tpt / 100;
1889                                 if (tpt >= search_tbl->expected_tpt[index])
1890                                         break;
1891                         }
1892                         search_tbl->current_rate =
1893                                 rate_n_flags_from_tbl(priv, search_tbl,
1894                                                       index, is_green);
1895                         update_search_tbl_counter = 1;
1896                         goto out;
1897                 }
1898                 tbl->action++;
1899                 if (tbl->action > IWL_MIMO3_SWITCH_GI)
1900                         tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1901
1902                 if (tbl->action == start_action)
1903                         break;
1904         }
1905         search_tbl->lq_type = LQ_NONE;
1906         return 0;
1907  out:
1908         lq_sta->search_better_tbl = 1;
1909         tbl->action++;
1910         if (tbl->action > IWL_MIMO3_SWITCH_GI)
1911                 tbl->action = IWL_MIMO3_SWITCH_ANTENNA1;
1912         if (update_search_tbl_counter)
1913                 search_tbl->action = tbl->action;
1914
1915         return 0;
1916
1917 }
1918
1919 /*
1920  * Check whether we should continue using same modulation mode, or
1921  * begin search for a new mode, based on:
1922  * 1) # tx successes or failures while using this mode
1923  * 2) # times calling this function
1924  * 3) elapsed time in this mode (not used, for now)
1925  */
1926 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1927 {
1928         struct iwl_scale_tbl_info *tbl;
1929         int i;
1930         int active_tbl;
1931         int flush_interval_passed = 0;
1932         struct iwl_priv *priv;
1933
1934         priv = lq_sta->drv;
1935         active_tbl = lq_sta->active_tbl;
1936
1937         tbl = &(lq_sta->lq_info[active_tbl]);
1938
1939         /* If we've been disallowing search, see if we should now allow it */
1940         if (lq_sta->stay_in_tbl) {
1941
1942                 /* Elapsed time using current modulation mode */
1943                 if (lq_sta->flush_timer)
1944                         flush_interval_passed =
1945                         time_after(jiffies,
1946                                         (unsigned long)(lq_sta->flush_timer +
1947                                         IWL_RATE_SCALE_FLUSH_INTVL));
1948
1949                 /*
1950                  * Check if we should allow search for new modulation mode.
1951                  * If many frames have failed or succeeded, or we've used
1952                  * this same modulation for a long time, allow search, and
1953                  * reset history stats that keep track of whether we should
1954                  * allow a new search.  Also (below) reset all bitmaps and
1955                  * stats in active history.
1956                  */
1957                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1958                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1959                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1960                      && (flush_interval_passed))) {
1961                         IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1962                                      lq_sta->total_failed,
1963                                      lq_sta->total_success,
1964                                      flush_interval_passed);
1965
1966                         /* Allow search for new mode */
1967                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1968                         lq_sta->total_failed = 0;
1969                         lq_sta->total_success = 0;
1970                         lq_sta->flush_timer = 0;
1971
1972                 /*
1973                  * Else if we've used this modulation mode enough repetitions
1974                  * (regardless of elapsed time or success/failure), reset
1975                  * history bitmaps and rate-specific stats for all rates in
1976                  * active table.
1977                  */
1978                 } else {
1979                         lq_sta->table_count++;
1980                         if (lq_sta->table_count >=
1981                             lq_sta->table_count_limit) {
1982                                 lq_sta->table_count = 0;
1983
1984                                 IWL_DEBUG_RATE(priv, "LQ: stay in table clear win\n");
1985                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1986                                         rs_rate_scale_clear_window(
1987                                                 &(tbl->win[i]));
1988                         }
1989                 }
1990
1991                 /* If transitioning to allow "search", reset all history
1992                  * bitmaps and stats in active table (this will become the new
1993                  * "search" table). */
1994                 if (!lq_sta->stay_in_tbl) {
1995                         for (i = 0; i < IWL_RATE_COUNT; i++)
1996                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1997                 }
1998         }
1999 }
2000
2001 /*
2002  * setup rate table in uCode
2003  * return rate_n_flags as used in the table
2004  */
2005 static u32 rs_update_rate_tbl(struct iwl_priv *priv,
2006                                 struct iwl_lq_sta *lq_sta,
2007                                 struct iwl_scale_tbl_info *tbl,
2008                                 int index, u8 is_green)
2009 {
2010         u32 rate;
2011
2012         /* Update uCode's rate table. */
2013         rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2014         rs_fill_link_cmd(priv, lq_sta, rate);
2015         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2016
2017         return rate;
2018 }
2019
2020 /*
2021  * Do rate scaling and search for new modulation mode.
2022  */
2023 static void rs_rate_scale_perform(struct iwl_priv *priv,
2024                                   struct sk_buff *skb,
2025                                   struct ieee80211_sta *sta,
2026                                   struct iwl_lq_sta *lq_sta)
2027 {
2028         struct ieee80211_hw *hw = priv->hw;
2029         struct ieee80211_conf *conf = &hw->conf;
2030         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2031         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2032         int low = IWL_RATE_INVALID;
2033         int high = IWL_RATE_INVALID;
2034         int index;
2035         int i;
2036         struct iwl_rate_scale_data *window = NULL;
2037         int current_tpt = IWL_INVALID_VALUE;
2038         int low_tpt = IWL_INVALID_VALUE;
2039         int high_tpt = IWL_INVALID_VALUE;
2040         u32 fail_count;
2041         s8 scale_action = 0;
2042         u16 rate_mask;
2043         u8 update_lq = 0;
2044         struct iwl_scale_tbl_info *tbl, *tbl1;
2045         u16 rate_scale_index_msk = 0;
2046         u32 rate;
2047         u8 is_green = 0;
2048         u8 active_tbl = 0;
2049         u8 done_search = 0;
2050         u16 high_low;
2051         s32 sr;
2052         u8 tid = MAX_TID_COUNT;
2053         struct iwl_tid_data *tid_data;
2054
2055         IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
2056
2057         /* Send management frames and NO_ACK data using lowest rate. */
2058         /* TODO: this could probably be improved.. */
2059         if (!ieee80211_is_data(hdr->frame_control) ||
2060             info->flags & IEEE80211_TX_CTL_NO_ACK)
2061                 return;
2062
2063         if (!sta || !lq_sta)
2064                 return;
2065
2066         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
2067
2068         tid = rs_tl_add_packet(lq_sta, hdr);
2069
2070         /*
2071          * Select rate-scale / modulation-mode table to work with in
2072          * the rest of this function:  "search" if searching for better
2073          * modulation mode, or "active" if doing rate scaling within a mode.
2074          */
2075         if (!lq_sta->search_better_tbl)
2076                 active_tbl = lq_sta->active_tbl;
2077         else
2078                 active_tbl = 1 - lq_sta->active_tbl;
2079
2080         tbl = &(lq_sta->lq_info[active_tbl]);
2081         if (is_legacy(tbl->lq_type))
2082                 lq_sta->is_green = 0;
2083         else
2084                 lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2085         is_green = lq_sta->is_green;
2086
2087         /* current tx rate */
2088         index = lq_sta->last_txrate_idx;
2089
2090         IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
2091                        tbl->lq_type);
2092
2093         /* rates available for this association, and for modulation mode */
2094         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
2095
2096         IWL_DEBUG_RATE(priv, "mask 0x%04X \n", rate_mask);
2097
2098         /* mask with station rate restriction */
2099         if (is_legacy(tbl->lq_type)) {
2100                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
2101                         /* supp_rates has no CCK bits in A mode */
2102                         rate_scale_index_msk = (u16) (rate_mask &
2103                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
2104                 else
2105                         rate_scale_index_msk = (u16) (rate_mask &
2106                                                       lq_sta->supp_rates);
2107
2108         } else
2109                 rate_scale_index_msk = rate_mask;
2110
2111         if (!rate_scale_index_msk)
2112                 rate_scale_index_msk = rate_mask;
2113
2114         if (!((1 << index) & rate_scale_index_msk)) {
2115                 IWL_ERR(priv, "Current Rate is not valid\n");
2116                 if (lq_sta->search_better_tbl) {
2117                         /* revert to active table if search table is not valid*/
2118                         tbl->lq_type = LQ_NONE;
2119                         lq_sta->search_better_tbl = 0;
2120                         tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2121                         /* get "active" rate info */
2122                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2123                         rate = rs_update_rate_tbl(priv, lq_sta,
2124                                                   tbl, index, is_green);
2125                 }
2126                 return;
2127         }
2128
2129         /* Get expected throughput table and history window for current rate */
2130         if (!tbl->expected_tpt) {
2131                 IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
2132                 return;
2133         }
2134
2135         /* force user max rate if set by user */
2136         if ((lq_sta->max_rate_idx != -1) &&
2137             (lq_sta->max_rate_idx < index)) {
2138                 index = lq_sta->max_rate_idx;
2139                 update_lq = 1;
2140                 window = &(tbl->win[index]);
2141                 goto lq_update;
2142         }
2143
2144         window = &(tbl->win[index]);
2145
2146         /*
2147          * If there is not enough history to calculate actual average
2148          * throughput, keep analyzing results of more tx frames, without
2149          * changing rate or mode (bypass most of the rest of this function).
2150          * Set up new rate table in uCode only if old rate is not supported
2151          * in current association (use new rate found above).
2152          */
2153         fail_count = window->counter - window->success_counter;
2154         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
2155                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
2156                 IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
2157                                "for index %d\n",
2158                                window->success_counter, window->counter, index);
2159
2160                 /* Can't calculate this yet; not enough history */
2161                 window->average_tpt = IWL_INVALID_VALUE;
2162
2163                 /* Should we stay with this modulation mode,
2164                  * or search for a new one? */
2165                 rs_stay_in_table(lq_sta);
2166
2167                 goto out;
2168         }
2169
2170         /* Else we have enough samples; calculate estimate of
2171          * actual average throughput */
2172
2173         BUG_ON(window->average_tpt != ((window->success_ratio *
2174                         tbl->expected_tpt[index] + 64) / 128));
2175
2176         /* If we are searching for better modulation mode, check success. */
2177         if (lq_sta->search_better_tbl &&
2178             (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI)) {
2179                 /* If good success, continue using the "search" mode;
2180                  * no need to send new link quality command, since we're
2181                  * continuing to use the setup that we've been trying. */
2182                 if (window->average_tpt > lq_sta->last_tpt) {
2183
2184                         IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
2185                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2186                                         window->success_ratio,
2187                                         window->average_tpt,
2188                                         lq_sta->last_tpt);
2189
2190                         if (!is_legacy(tbl->lq_type))
2191                                 lq_sta->enable_counter = 1;
2192
2193                         /* Swap tables; "search" becomes "active" */
2194                         lq_sta->active_tbl = active_tbl;
2195                         current_tpt = window->average_tpt;
2196
2197                 /* Else poor success; go back to mode in "active" table */
2198                 } else {
2199
2200                         IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
2201                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
2202                                         window->success_ratio,
2203                                         window->average_tpt,
2204                                         lq_sta->last_tpt);
2205
2206                         /* Nullify "search" table */
2207                         tbl->lq_type = LQ_NONE;
2208
2209                         /* Revert to "active" table */
2210                         active_tbl = lq_sta->active_tbl;
2211                         tbl = &(lq_sta->lq_info[active_tbl]);
2212
2213                         /* Revert to "active" rate and throughput info */
2214                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2215                         current_tpt = lq_sta->last_tpt;
2216
2217                         /* Need to set up a new rate table in uCode */
2218                         update_lq = 1;
2219                 }
2220
2221                 /* Either way, we've made a decision; modulation mode
2222                  * search is done, allow rate adjustment next time. */
2223                 lq_sta->search_better_tbl = 0;
2224                 done_search = 1;        /* Don't switch modes below! */
2225                 goto lq_update;
2226         }
2227
2228         /* (Else) not in search of better modulation mode, try for better
2229          * starting rate, while staying in this mode. */
2230         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
2231                                         tbl->lq_type);
2232         low = high_low & 0xff;
2233         high = (high_low >> 8) & 0xff;
2234
2235         /* If user set max rate, dont allow higher than user constrain */
2236         if ((lq_sta->max_rate_idx != -1) &&
2237             (lq_sta->max_rate_idx < high))
2238                 high = IWL_RATE_INVALID;
2239
2240         sr = window->success_ratio;
2241
2242         /* Collect measured throughputs for current and adjacent rates */
2243         current_tpt = window->average_tpt;
2244         if (low != IWL_RATE_INVALID)
2245                 low_tpt = tbl->win[low].average_tpt;
2246         if (high != IWL_RATE_INVALID)
2247                 high_tpt = tbl->win[high].average_tpt;
2248
2249         scale_action = 0;
2250
2251         /* Too many failures, decrease rate */
2252         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
2253                 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
2254                 scale_action = -1;
2255
2256         /* No throughput measured yet for adjacent rates; try increase. */
2257         } else if ((low_tpt == IWL_INVALID_VALUE) &&
2258                    (high_tpt == IWL_INVALID_VALUE)) {
2259
2260                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
2261                         scale_action = 1;
2262                 else if (low != IWL_RATE_INVALID)
2263                         scale_action = 0;
2264         }
2265
2266         /* Both adjacent throughputs are measured, but neither one has better
2267          * throughput; we're using the best rate, don't change it! */
2268         else if ((low_tpt != IWL_INVALID_VALUE) &&
2269                  (high_tpt != IWL_INVALID_VALUE) &&
2270                  (low_tpt < current_tpt) &&
2271                  (high_tpt < current_tpt))
2272                 scale_action = 0;
2273
2274         /* At least one adjacent rate's throughput is measured,
2275          * and may have better performance. */
2276         else {
2277                 /* Higher adjacent rate's throughput is measured */
2278                 if (high_tpt != IWL_INVALID_VALUE) {
2279                         /* Higher rate has better throughput */
2280                         if (high_tpt > current_tpt &&
2281                                         sr >= IWL_RATE_INCREASE_TH) {
2282                                 scale_action = 1;
2283                         } else {
2284                                 scale_action = 0;
2285                         }
2286
2287                 /* Lower adjacent rate's throughput is measured */
2288                 } else if (low_tpt != IWL_INVALID_VALUE) {
2289                         /* Lower rate has better throughput */
2290                         if (low_tpt > current_tpt) {
2291                                 IWL_DEBUG_RATE(priv,
2292                                     "decrease rate because of low tpt\n");
2293                                 scale_action = -1;
2294                         } else if (sr >= IWL_RATE_INCREASE_TH) {
2295                                 scale_action = 1;
2296                         }
2297                 }
2298         }
2299
2300         /* Sanity check; asked for decrease, but success rate or throughput
2301          * has been good at old rate.  Don't change it. */
2302         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
2303                     ((sr > IWL_RATE_HIGH_TH) ||
2304                      (current_tpt > (100 * tbl->expected_tpt[low]))))
2305                 scale_action = 0;
2306         if (!iwl_ht_enabled(priv) && !is_legacy(tbl->lq_type))
2307                 scale_action = -1;
2308         if (iwl_tx_ant_restriction(priv) != IWL_ANT_OK_MULTI &&
2309                 (is_mimo2(tbl->lq_type) || is_mimo3(tbl->lq_type)))
2310                 scale_action = -1;
2311         switch (scale_action) {
2312         case -1:
2313                 /* Decrease starting rate, update uCode's rate table */
2314                 if (low != IWL_RATE_INVALID) {
2315                         update_lq = 1;
2316                         index = low;
2317                 }
2318
2319                 break;
2320         case 1:
2321                 /* Increase starting rate, update uCode's rate table */
2322                 if (high != IWL_RATE_INVALID) {
2323                         update_lq = 1;
2324                         index = high;
2325                 }
2326
2327                 break;
2328         case 0:
2329                 /* No change */
2330         default:
2331                 break;
2332         }
2333
2334         IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
2335                     "high %d type %d\n",
2336                      index, scale_action, low, high, tbl->lq_type);
2337
2338 lq_update:
2339         /* Replace uCode's rate table for the destination station. */
2340         if (update_lq)
2341                 rate = rs_update_rate_tbl(priv, lq_sta,
2342                                           tbl, index, is_green);
2343
2344         if (iwl_tx_ant_restriction(priv) == IWL_ANT_OK_MULTI) {
2345                 /* Should we stay with this modulation mode,
2346                  * or search for a new one? */
2347                 rs_stay_in_table(lq_sta);
2348         }
2349         /*
2350          * Search for new modulation mode if we're:
2351          * 1)  Not changing rates right now
2352          * 2)  Not just finishing up a search
2353          * 3)  Allowing a new search
2354          */
2355         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
2356                 /* Save current throughput to compare with "search" throughput*/
2357                 lq_sta->last_tpt = current_tpt;
2358
2359                 /* Select a new "search" modulation mode to try.
2360                  * If one is found, set up the new "search" table. */
2361                 if (is_legacy(tbl->lq_type))
2362                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
2363                 else if (is_siso(tbl->lq_type))
2364                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2365                 else if (is_mimo2(tbl->lq_type))
2366                         rs_move_mimo2_to_other(priv, lq_sta, conf, sta, index);
2367                 else
2368                         rs_move_mimo3_to_other(priv, lq_sta, conf, sta, index);
2369
2370                 /* If new "search" mode was selected, set up in uCode table */
2371                 if (lq_sta->search_better_tbl) {
2372                         /* Access the "search" table, clear its history. */
2373                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2374                         for (i = 0; i < IWL_RATE_COUNT; i++)
2375                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2376
2377                         /* Use new "search" start rate */
2378                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
2379
2380                         IWL_DEBUG_RATE(priv, "Switch current  mcs: %X index: %d\n",
2381                                      tbl->current_rate, index);
2382                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
2383                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2384                 } else
2385                         done_search = 1;
2386         }
2387
2388         if (done_search && !lq_sta->stay_in_tbl) {
2389                 /* If the "active" (non-search) mode was legacy,
2390                  * and we've tried switching antennas,
2391                  * but we haven't been able to try HT modes (not available),
2392                  * stay with best antenna legacy modulation for a while
2393                  * before next round of mode comparisons. */
2394                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2395                 if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2396                     lq_sta->action_counter > tbl1->max_search) {
2397                         IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2398                         rs_set_stay_in_table(priv, 1, lq_sta);
2399                 }
2400
2401                 /* If we're in an HT mode, and all 3 mode switch actions
2402                  * have been tried and compared, stay in this best modulation
2403                  * mode for a while before next round of mode comparisons. */
2404                 if (lq_sta->enable_counter &&
2405                     (lq_sta->action_counter >= tbl1->max_search) &&
2406                     iwl_ht_enabled(priv)) {
2407                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2408                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2409                             (tid != MAX_TID_COUNT)) {
2410                                 tid_data =
2411                                    &priv->stations[lq_sta->lq.sta_id].tid[tid];
2412                                 if (tid_data->agg.state == IWL_AGG_OFF) {
2413                                         IWL_DEBUG_RATE(priv,
2414                                                        "try to aggregate tid %d\n",
2415                                                        tid);
2416                                         rs_tl_turn_on_agg(priv, tid,
2417                                                           lq_sta, sta);
2418                                 }
2419                         }
2420                         rs_set_stay_in_table(priv, 0, lq_sta);
2421                 }
2422         }
2423
2424 out:
2425         tbl->current_rate = rate_n_flags_from_tbl(priv, tbl, index, is_green);
2426         i = index;
2427         lq_sta->last_txrate_idx = i;
2428
2429         return;
2430 }
2431
2432
2433 static void rs_initialize_lq(struct iwl_priv *priv,
2434                              struct ieee80211_conf *conf,
2435                              struct ieee80211_sta *sta,
2436                              struct iwl_lq_sta *lq_sta)
2437 {
2438         struct iwl_scale_tbl_info *tbl;
2439         int rate_idx;
2440         int i;
2441         u32 rate;
2442         u8 use_green = rs_use_green(sta, &priv->current_ht_config);
2443         u8 active_tbl = 0;
2444         u8 valid_tx_ant;
2445
2446         if (!sta || !lq_sta)
2447                 goto out;
2448
2449         i = lq_sta->last_txrate_idx;
2450
2451         if ((lq_sta->lq.sta_id == 0xff) &&
2452             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2453                 goto out;
2454
2455         valid_tx_ant = priv->hw_params.valid_tx_ant;
2456
2457         if (!lq_sta->search_better_tbl)
2458                 active_tbl = lq_sta->active_tbl;
2459         else
2460                 active_tbl = 1 - lq_sta->active_tbl;
2461
2462         tbl = &(lq_sta->lq_info[active_tbl]);
2463
2464         if ((i < 0) || (i >= IWL_RATE_COUNT))
2465                 i = 0;
2466
2467         rate = iwl_rates[i].plcp;
2468         tbl->ant_type = first_antenna(valid_tx_ant);
2469         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2470
2471         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2472                 rate |= RATE_MCS_CCK_MSK;
2473
2474         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2475         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2476             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2477
2478         rate = rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2479         tbl->current_rate = rate;
2480         rs_set_expected_tpt_table(lq_sta, tbl);
2481         rs_fill_link_cmd(NULL, lq_sta, rate);
2482         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2483  out:
2484         return;
2485 }
2486
2487 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2488                         struct ieee80211_tx_rate_control *txrc)
2489 {
2490
2491         struct sk_buff *skb = txrc->skb;
2492         struct ieee80211_supported_band *sband = txrc->sband;
2493         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2494         struct ieee80211_conf *conf = &priv->hw->conf;
2495         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2496         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2497         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2498         struct iwl_lq_sta *lq_sta = priv_sta;
2499         int rate_idx;
2500
2501         IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2502
2503         /* Get max rate if user set max rate */
2504         if (lq_sta) {
2505                 lq_sta->max_rate_idx = txrc->max_rate_idx;
2506                 if ((sband->band == IEEE80211_BAND_5GHZ) &&
2507                     (lq_sta->max_rate_idx != -1))
2508                         lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2509                 if ((lq_sta->max_rate_idx < 0) ||
2510                     (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2511                         lq_sta->max_rate_idx = -1;
2512         }
2513
2514         /* Send management frames and NO_ACK data using lowest rate. */
2515         if (rate_control_send_low(sta, priv_sta, txrc))
2516                 return;
2517
2518         rate_idx  = lq_sta->last_txrate_idx;
2519
2520         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2521             !lq_sta->ibss_sta_added) {
2522                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2523
2524                 if (sta_id == IWL_INVALID_STATION) {
2525                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
2526                                        hdr->addr1);
2527                         sta_id = iwl_add_station(priv, hdr->addr1,
2528                                                 false, CMD_ASYNC, ht_cap);
2529                 }
2530                 if ((sta_id != IWL_INVALID_STATION)) {
2531                         lq_sta->lq.sta_id = sta_id;
2532                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2533                         lq_sta->ibss_sta_added = 1;
2534                         rs_initialize_lq(priv, conf, sta, lq_sta);
2535                 }
2536         }
2537
2538         if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2539                 rate_idx -= IWL_FIRST_OFDM_RATE;
2540                 /* 6M and 9M shared same MCS index */
2541                 rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2542                 if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2543                     IWL_RATE_MIMO3_6M_PLCP)
2544                         rate_idx = rate_idx + (2 * MCS_INDEX_PER_STREAM);
2545                 else if (rs_extract_rate(lq_sta->last_rate_n_flags) >=
2546                          IWL_RATE_MIMO2_6M_PLCP)
2547                         rate_idx = rate_idx + MCS_INDEX_PER_STREAM;
2548                 info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2549                 if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2550                         info->control.rates[0].flags |= IEEE80211_TX_RC_SHORT_GI;
2551                 if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2552                         info->control.rates[0].flags |= IEEE80211_TX_RC_DUP_DATA;
2553                 if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2554                         info->control.rates[0].flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
2555                 if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2556                         info->control.rates[0].flags |= IEEE80211_TX_RC_GREEN_FIELD;
2557         } else {
2558                 /* Check for invalid rates */
2559                 if ((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT_LEGACY) ||
2560                                 ((sband->band == IEEE80211_BAND_5GHZ) &&
2561                                  (rate_idx < IWL_FIRST_OFDM_RATE)))
2562                         rate_idx = rate_lowest_index(sband, sta);
2563                 /* On valid 5 GHz rate, adjust index */
2564                 else if (sband->band == IEEE80211_BAND_5GHZ)
2565                         rate_idx -= IWL_FIRST_OFDM_RATE;
2566                 info->control.rates[0].flags = 0;
2567         }
2568         info->control.rates[0].idx = rate_idx;
2569
2570 }
2571
2572 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2573                           gfp_t gfp)
2574 {
2575         struct iwl_lq_sta *lq_sta;
2576         struct iwl_priv *priv;
2577         int i, j;
2578
2579         priv = (struct iwl_priv *)priv_rate;
2580         IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2581
2582         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2583
2584         if (lq_sta == NULL)
2585                 return NULL;
2586         lq_sta->lq.sta_id = 0xff;
2587
2588
2589         for (j = 0; j < LQ_SIZE; j++)
2590                 for (i = 0; i < IWL_RATE_COUNT; i++)
2591                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2592
2593         return lq_sta;
2594 }
2595
2596 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2597                          struct ieee80211_sta *sta, void *priv_sta)
2598 {
2599         int i, j;
2600         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2601         struct ieee80211_conf *conf = &priv->hw->conf;
2602         struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2603         struct iwl_lq_sta *lq_sta = priv_sta;
2604
2605         lq_sta->flush_timer = 0;
2606         lq_sta->supp_rates = sta->supp_rates[sband->band];
2607         for (j = 0; j < LQ_SIZE; j++)
2608                 for (i = 0; i < IWL_RATE_COUNT; i++)
2609                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2610
2611         IWL_DEBUG_RATE(priv, "LQ: *** rate scale station global init ***\n");
2612         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2613          * the lowest or the highest rate.. Could consider using RSSI from
2614          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2615          * after assoc.. */
2616
2617         lq_sta->ibss_sta_added = 0;
2618         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2619                 u8 sta_id = iwl_find_station(priv,
2620                                                                 sta->addr);
2621
2622                 /* for IBSS the call are from tasklet */
2623                 IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2624
2625                 if (sta_id == IWL_INVALID_STATION) {
2626                         IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n", sta->addr);
2627                         sta_id = iwl_add_station(priv, sta->addr, false,
2628                                                 CMD_ASYNC, ht_cap);
2629                 }
2630                 if ((sta_id != IWL_INVALID_STATION)) {
2631                         lq_sta->lq.sta_id = sta_id;
2632                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2633                 }
2634                 /* FIXME: this is w/a remove it later */
2635                 priv->assoc_station_added = 1;
2636         }
2637
2638         lq_sta->is_dup = 0;
2639         lq_sta->max_rate_idx = -1;
2640         lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2641         lq_sta->is_green = rs_use_green(sta, &priv->current_ht_config);
2642         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2643         lq_sta->active_rate_basic = priv->active_rate_basic;
2644         lq_sta->band = priv->band;
2645         /*
2646          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2647          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2648          */
2649         lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
2650         lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
2651         lq_sta->active_siso_rate &= ~((u16)0x2);
2652         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2653
2654         /* Same here */
2655         lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
2656         lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
2657         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2658         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2659
2660         lq_sta->active_mimo3_rate = ht_cap->mcs.rx_mask[2] << 1;
2661         lq_sta->active_mimo3_rate |= ht_cap->mcs.rx_mask[2] & 0x1;
2662         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2663         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2664
2665         IWL_DEBUG_RATE(priv, "SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2666                      lq_sta->active_siso_rate,
2667                      lq_sta->active_mimo2_rate,
2668                      lq_sta->active_mimo3_rate);
2669
2670         /* These values will be overridden later */
2671         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2672         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2673
2674         /* as default allow aggregation for all tids */
2675         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2676         lq_sta->drv = priv;
2677
2678         /* Set last_txrate_idx to lowest rate */
2679         lq_sta->last_txrate_idx = rate_lowest_index(sband, sta);
2680         if (sband->band == IEEE80211_BAND_5GHZ)
2681                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2682
2683         rs_initialize_lq(priv, conf, sta, lq_sta);
2684 }
2685
2686 static void rs_fill_link_cmd(struct iwl_priv *priv,
2687                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2688 {
2689         struct iwl_scale_tbl_info tbl_type;
2690         int index = 0;
2691         int rate_idx;
2692         int repeat_rate = 0;
2693         u8 ant_toggle_cnt = 0;
2694         u8 use_ht_possible = 1;
2695         u8 valid_tx_ant = 0;
2696         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2697
2698         /* Override starting rate (index 0) if needed for debug purposes */
2699         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2700
2701         /* Interpret new_rate (rate_n_flags) */
2702         memset(&tbl_type, 0, sizeof(tbl_type));
2703         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2704                                   &tbl_type, &rate_idx);
2705
2706         /* How many times should we repeat the initial rate? */
2707         if (is_legacy(tbl_type.lq_type)) {
2708                 ant_toggle_cnt = 1;
2709                 repeat_rate = IWL_NUMBER_TRY;
2710         } else {
2711                 repeat_rate = IWL_HT_NUMBER_TRY;
2712         }
2713
2714         lq_cmd->general_params.mimo_delimiter =
2715                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2716
2717         /* Fill 1st table entry (index 0) */
2718         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2719
2720         if (num_of_ant(tbl_type.ant_type) == 1) {
2721                 lq_cmd->general_params.single_stream_ant_msk =
2722                                                 tbl_type.ant_type;
2723         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2724                 lq_cmd->general_params.dual_stream_ant_msk =
2725                                                 tbl_type.ant_type;
2726         } /* otherwise we don't modify the existing value */
2727
2728         index++;
2729         repeat_rate--;
2730
2731         if (priv)
2732                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2733
2734         /* Fill rest of rate table */
2735         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2736                 /* Repeat initial/next rate.
2737                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2738                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2739                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2740                         if (is_legacy(tbl_type.lq_type)) {
2741                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2742                                         ant_toggle_cnt++;
2743                                 else if (priv &&
2744                                          rs_toggle_antenna(valid_tx_ant,
2745                                                         &new_rate, &tbl_type))
2746                                         ant_toggle_cnt = 1;
2747 }
2748
2749                         /* Override next rate if needed for debug purposes */
2750                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2751
2752                         /* Fill next table entry */
2753                         lq_cmd->rs_table[index].rate_n_flags =
2754                                         cpu_to_le32(new_rate);
2755                         repeat_rate--;
2756                         index++;
2757                 }
2758
2759                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2760                                                 &rate_idx);
2761
2762                 /* Indicate to uCode which entries might be MIMO.
2763                  * If initial rate was MIMO, this will finally end up
2764                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2765                 if (is_mimo(tbl_type.lq_type))
2766                         lq_cmd->general_params.mimo_delimiter = index;
2767
2768                 /* Get next rate */
2769                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2770                                              use_ht_possible);
2771
2772                 /* How many times should we repeat the next rate? */
2773                 if (is_legacy(tbl_type.lq_type)) {
2774                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2775                                 ant_toggle_cnt++;
2776                         else if (priv &&
2777                                  rs_toggle_antenna(valid_tx_ant,
2778                                                    &new_rate, &tbl_type))
2779                                 ant_toggle_cnt = 1;
2780
2781                         repeat_rate = IWL_NUMBER_TRY;
2782                 } else {
2783                         repeat_rate = IWL_HT_NUMBER_TRY;
2784                 }
2785
2786                 /* Don't allow HT rates after next pass.
2787                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2788                 use_ht_possible = 0;
2789
2790                 /* Override next rate if needed for debug purposes */
2791                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2792
2793                 /* Fill next table entry */
2794                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2795
2796                 index++;
2797                 repeat_rate--;
2798         }
2799
2800         lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_MAX;
2801         lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2802         lq_cmd->agg_params.agg_time_limit =
2803                 cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2804 }
2805
2806 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2807 {
2808         return hw->priv;
2809 }
2810 /* rate scale requires free function to be implemented */
2811 static void rs_free(void *priv_rate)
2812 {
2813         return;
2814 }
2815
2816 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2817                         void *priv_sta)
2818 {
2819         struct iwl_lq_sta *lq_sta = priv_sta;
2820         struct iwl_priv *priv __maybe_unused = priv_r;
2821
2822         IWL_DEBUG_RATE(priv, "enter\n");
2823         kfree(lq_sta);
2824         IWL_DEBUG_RATE(priv, "leave\n");
2825 }
2826
2827
2828 #ifdef CONFIG_MAC80211_DEBUGFS
2829 static int open_file_generic(struct inode *inode, struct file *file)
2830 {
2831         file->private_data = inode->i_private;
2832         return 0;
2833 }
2834 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2835                              u32 *rate_n_flags, int index)
2836 {
2837         struct iwl_priv *priv;
2838         u8 valid_tx_ant;
2839         u8 ant_sel_tx;
2840
2841         priv = lq_sta->drv;
2842         valid_tx_ant = priv->hw_params.valid_tx_ant;
2843         if (lq_sta->dbg_fixed_rate) {
2844                 ant_sel_tx =
2845                   ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2846                   >> RATE_MCS_ANT_POS);
2847                 if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2848                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2849                         IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2850                 } else {
2851                         lq_sta->dbg_fixed_rate = 0;
2852                         IWL_ERR(priv,
2853                             "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2854                             ant_sel_tx, valid_tx_ant);
2855                         IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2856                 }
2857         } else {
2858                 IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2859         }
2860 }
2861
2862 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2863                         const char __user *user_buf, size_t count, loff_t *ppos)
2864 {
2865         struct iwl_lq_sta *lq_sta = file->private_data;
2866         struct iwl_priv *priv;
2867         char buf[64];
2868         int buf_size;
2869         u32 parsed_rate;
2870
2871         priv = lq_sta->drv;
2872         memset(buf, 0, sizeof(buf));
2873         buf_size = min(count, sizeof(buf) -  1);
2874         if (copy_from_user(buf, user_buf, buf_size))
2875                 return -EFAULT;
2876
2877         if (sscanf(buf, "%x", &parsed_rate) == 1)
2878                 lq_sta->dbg_fixed_rate = parsed_rate;
2879         else
2880                 lq_sta->dbg_fixed_rate = 0;
2881
2882         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2883         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2884         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2885         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2886
2887         IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2888                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2889
2890         if (lq_sta->dbg_fixed_rate) {
2891                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2892                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2893         }
2894
2895         return count;
2896 }
2897
2898 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2899                         char __user *user_buf, size_t count, loff_t *ppos)
2900 {
2901         char *buff;
2902         int desc = 0;
2903         int i = 0;
2904         int index = 0;
2905         ssize_t ret;
2906
2907         struct iwl_lq_sta *lq_sta = file->private_data;
2908         struct iwl_priv *priv;
2909         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2910
2911         priv = lq_sta->drv;
2912         buff = kmalloc(1024, GFP_KERNEL);
2913         if (!buff)
2914                 return -ENOMEM;
2915
2916         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2917         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2918                         lq_sta->total_failed, lq_sta->total_success,
2919                         lq_sta->active_legacy_rate);
2920         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2921                         lq_sta->dbg_fixed_rate);
2922         desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2923             (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2924             (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2925             (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2926         desc += sprintf(buff+desc, "lq type %s\n",
2927            (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2928         if (is_Ht(tbl->lq_type)) {
2929                 desc += sprintf(buff+desc, " %s",
2930                    (is_siso(tbl->lq_type)) ? "SISO" :
2931                    ((is_mimo2(tbl->lq_type)) ? "MIMO2" : "MIMO3"));
2932                    desc += sprintf(buff+desc, " %s",
2933                    (tbl->is_ht40) ? "40MHz" : "20MHz");
2934                    desc += sprintf(buff+desc, " %s %s\n", (tbl->is_SGI) ? "SGI" : "",
2935                    (lq_sta->is_green) ? "GF enabled" : "");
2936         }
2937         desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2938                 lq_sta->last_rate_n_flags);
2939         desc += sprintf(buff+desc, "general:"
2940                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2941                 lq_sta->lq.general_params.flags,
2942                 lq_sta->lq.general_params.mimo_delimiter,
2943                 lq_sta->lq.general_params.single_stream_ant_msk,
2944                 lq_sta->lq.general_params.dual_stream_ant_msk);
2945
2946         desc += sprintf(buff+desc, "agg:"
2947                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2948                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2949                         lq_sta->lq.agg_params.agg_dis_start_th,
2950                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2951
2952         desc += sprintf(buff+desc,
2953                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2954                         lq_sta->lq.general_params.start_rate_index[0],
2955                         lq_sta->lq.general_params.start_rate_index[1],
2956                         lq_sta->lq.general_params.start_rate_index[2],
2957                         lq_sta->lq.general_params.start_rate_index[3]);
2958
2959         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2960                 index = iwl_hwrate_to_plcp_idx(
2961                         le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2962                 if (is_legacy(tbl->lq_type)) {
2963                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2964                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2965                                 iwl_rate_mcs[index].mbps);
2966                 } else {
2967                         desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps (%s)\n",
2968                                 i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2969                                 iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
2970                 }
2971         }
2972
2973         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2974         kfree(buff);
2975         return ret;
2976 }
2977
2978 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2979         .write = rs_sta_dbgfs_scale_table_write,
2980         .read = rs_sta_dbgfs_scale_table_read,
2981         .open = open_file_generic,
2982 };
2983 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2984                         char __user *user_buf, size_t count, loff_t *ppos)
2985 {
2986         char *buff;
2987         int desc = 0;
2988         int i, j;
2989         ssize_t ret;
2990
2991         struct iwl_lq_sta *lq_sta = file->private_data;
2992
2993         buff = kmalloc(1024, GFP_KERNEL);
2994         if (!buff)
2995                 return -ENOMEM;
2996
2997         for (i = 0; i < LQ_SIZE; i++) {
2998                 desc += sprintf(buff+desc,
2999                                 "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
3000                                 "rate=0x%X\n",
3001                                 lq_sta->active_tbl == i ? "*" : "x",
3002                                 lq_sta->lq_info[i].lq_type,
3003                                 lq_sta->lq_info[i].is_SGI,
3004                                 lq_sta->lq_info[i].is_ht40,
3005                                 lq_sta->lq_info[i].is_dup,
3006                                 lq_sta->is_green,
3007                                 lq_sta->lq_info[i].current_rate);
3008                 for (j = 0; j < IWL_RATE_COUNT; j++) {
3009                         desc += sprintf(buff+desc,
3010                                 "counter=%d success=%d %%=%d\n",
3011                                 lq_sta->lq_info[i].win[j].counter,
3012                                 lq_sta->lq_info[i].win[j].success_counter,
3013                                 lq_sta->lq_info[i].win[j].success_ratio);
3014                 }
3015         }
3016         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3017         kfree(buff);
3018         return ret;
3019 }
3020
3021 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
3022         .read = rs_sta_dbgfs_stats_table_read,
3023         .open = open_file_generic,
3024 };
3025
3026 static ssize_t rs_sta_dbgfs_rate_scale_data_read(struct file *file,
3027                         char __user *user_buf, size_t count, loff_t *ppos)
3028 {
3029         char buff[120];
3030         int desc = 0;
3031         ssize_t ret;
3032
3033         struct iwl_lq_sta *lq_sta = file->private_data;
3034         struct iwl_priv *priv;
3035         struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
3036
3037         priv = lq_sta->drv;
3038
3039         if (is_Ht(tbl->lq_type))
3040                 desc += sprintf(buff+desc,
3041                                 "Bit Rate= %d Mb/s\n",
3042                                 tbl->expected_tpt[lq_sta->last_txrate_idx]);
3043         else
3044                 desc += sprintf(buff+desc,
3045                                 "Bit Rate= %d Mb/s\n",
3046                                 iwl_rates[lq_sta->last_txrate_idx].ieee >> 1);
3047         desc += sprintf(buff+desc,
3048                         "Signal Level= %d dBm\tNoise Level= %d dBm\n",
3049                         priv->last_rx_rssi, priv->last_rx_noise);
3050         desc += sprintf(buff+desc,
3051                         "Tsf= 0x%llx\tBeacon time= 0x%08X\n",
3052                         priv->last_tsf, priv->last_beacon_time);
3053
3054         ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
3055         return ret;
3056 }
3057
3058 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
3059         .read = rs_sta_dbgfs_rate_scale_data_read,
3060         .open = open_file_generic,
3061 };
3062
3063 static void rs_add_debugfs(void *priv, void *priv_sta,
3064                                         struct dentry *dir)
3065 {
3066         struct iwl_lq_sta *lq_sta = priv_sta;
3067         lq_sta->rs_sta_dbgfs_scale_table_file =
3068                 debugfs_create_file("rate_scale_table", 0600, dir,
3069                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
3070         lq_sta->rs_sta_dbgfs_stats_table_file =
3071                 debugfs_create_file("rate_stats_table", 0600, dir,
3072                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
3073         lq_sta->rs_sta_dbgfs_rate_scale_data_file =
3074                 debugfs_create_file("rate_scale_data", 0600, dir,
3075                         lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
3076         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
3077                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
3078                 &lq_sta->tx_agg_tid_en);
3079
3080 }
3081
3082 static void rs_remove_debugfs(void *priv, void *priv_sta)
3083 {
3084         struct iwl_lq_sta *lq_sta = priv_sta;
3085         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
3086         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
3087         debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
3088         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
3089 }
3090 #endif
3091
3092 static struct rate_control_ops rs_ops = {
3093         .module = NULL,
3094         .name = RS_NAME,
3095         .tx_status = rs_tx_status,
3096         .get_rate = rs_get_rate,
3097         .rate_init = rs_rate_init,
3098         .alloc = rs_alloc,
3099         .free = rs_free,
3100         .alloc_sta = rs_alloc_sta,
3101         .free_sta = rs_free_sta,
3102 #ifdef CONFIG_MAC80211_DEBUGFS
3103         .add_sta_debugfs = rs_add_debugfs,
3104         .remove_sta_debugfs = rs_remove_debugfs,
3105 #endif
3106 };
3107
3108 int iwlagn_rate_control_register(void)
3109 {
3110         return ieee80211_rate_control_register(&rs_ops);
3111 }
3112
3113 void iwlagn_rate_control_unregister(void)
3114 {
3115         ieee80211_rate_control_unregister(&rs_ops);
3116 }
3117