drivers/net/wireless/iwlwifi/iwl-4965-rs.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2005 - 2007 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  * James P. Ketrenos <ipw2100-admin@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 #include <net/ieee80211.h>
  32
  33 #include <linux/netdevice.h>
  34 #include <linux/etherdevice.h>
  35 #include <linux/delay.h>
  36
  37 #include <linux/workqueue.h>
  38
  39 #include "../net/mac80211/ieee80211_rate.h"
  40
  41 #include "iwl-4965.h"
  42 #include "iwl-helpers.h"
  43
  44 #define RS_NAME "iwl-4965-rs"
  45
  46 #define NUM_TRY_BEFORE_ANTENNA_TOGGLE 1
  47 #define IWL_NUMBER_TRY      1
  48 #define IWL_HT_NUMBER_TRY   3
  49
  50 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
  51 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
  52 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
  53
  54 /* max time to accum history 2 seconds */
  55 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
  56
  57 static u8 rs_ht_to_legacy[] = {
  58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
  60         IWL_RATE_6M_INDEX,
  61         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
  62         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
  63         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
  64         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
  65 };
  66
  67 struct iwl4965_rate {
  68         u32 rate_n_flags;
  69 } __attribute__ ((packed));
  70
  71 /**
  72  * struct iwl4965_rate_scale_data -- tx success history for one rate
  73  */
  74 struct iwl4965_rate_scale_data {
  75         u64 data;               /* bitmap of successful frames */
  76         s32 success_counter;    /* number of frames successful */
  77         s32 success_ratio;      /* per-cent * 128  */
  78         s32 counter;            /* number of frames attempted */
  79         s32 average_tpt;        /* success ratio * expected throughput */
  80         unsigned long stamp;
  81 };
  82
  83 /**
  84  * struct iwl4965_scale_tbl_info -- tx params and success history for all rates
  85  *
  86  * There are two of these in struct iwl_rate_scale_priv,
  87  * one for "active", and one for "search".
  88  */
  89 struct iwl4965_scale_tbl_info {
  90         enum iwl4965_table_type lq_type;
  91         enum iwl4965_antenna_type antenna_type;
  92         u8 is_SGI;      /* 1 = short guard interval */
  93         u8 is_fat;      /* 1 = 40 MHz channel width */
  94         u8 is_dup;      /* 1 = duplicated data streams */
  95         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
  96         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
  97         struct iwl4965_rate current_rate;  /* rate_n_flags, uCode API format */
  98         struct iwl4965_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
  99 };
 100
 101 /**
 102  * struct iwl_rate_scale_priv -- driver's rate scaling private structure
 103  *
 104  * Pointer to this gets passed back and forth between driver and mac80211.
 105  */
 106 struct iwl4965_lq_sta {
 107         u8 active_tbl;          /* index of active table, range 0-1 */
 108         u8 enable_counter;      /* indicates HT mode */
 109         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
 110         u8 search_better_tbl;   /* 1: currently trying alternate mode */
 111         s32 last_tpt;
 112
 113         /* The following determine when to search for a new mode */
 114         u32 table_count_limit;
 115         u32 max_failure_limit;  /* # failed frames before new search */
 116         u32 max_success_limit;  /* # successful frames before new search */
 117         u32 table_count;
 118         u32 total_failed;       /* total failed frames, any/all rates */
 119         u32 total_success;      /* total successful frames, any/all rates */
 120         u32 flush_timer;        /* time staying in mode before new search */
 121
 122         u8 action_counter;      /* # mode-switch actions tried */
 123         u8 antenna;
 124         u8 valid_antenna;
 125         u8 is_green;
 126         u8 is_dup;
 127         u8 phymode;
 128         u8 ibss_sta_added;
 129
 130         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
 131         u32 supp_rates;
 132         u16 active_rate;
 133         u16 active_siso_rate;
 134         u16 active_mimo_rate;
 135         u16 active_rate_basic;
 136
 137         struct iwl4965_link_quality_cmd lq;
 138         struct iwl4965_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
 139 #ifdef CONFIG_MAC80211_DEBUGFS
 140         struct dentry *rs_sta_dbgfs_scale_table_file;
 141         struct dentry *rs_sta_dbgfs_stats_table_file;
 142         struct iwl4965_rate dbg_fixed;
 143         struct iwl4965_priv *drv;
 144 #endif
 145 };
 146
 147 static void rs_rate_scale_perform(struct iwl4965_priv *priv,
 148                                    struct net_device *dev,
 149                                    struct ieee80211_hdr *hdr,
 150                                    struct sta_info *sta);
 151 static void rs_fill_link_cmd(struct iwl4965_lq_sta *lq_sta,
 152                              struct iwl4965_rate *tx_mcs,
 153                              struct iwl4965_link_quality_cmd *tbl);
 154
 155
 156 #ifdef CONFIG_MAC80211_DEBUGFS
 157 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
 158                                 struct iwl4965_rate *mcs, int index);
 159 #else
 160 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
 161                                 struct iwl4965_rate *mcs, int index)
 162 {}
 163 #endif
 164
 165 /*
 166  * Expected throughput metrics for following rates:
 167  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
 168  * "G" is the only table that supports CCK (the first 4 rates).
 169  */
 170 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
 171         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
 172 };
 173
 174 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
 175         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
 176 };
 177
 178 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
 179         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
 180 };
 181
 182 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
 183         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
 184 };
 185
 186 static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
 187         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
 188 };
 189
 190 static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
 191         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
 192 };
 193
 194 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
 195         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
 196 };
 197
 198 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
 199         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
 200 };
 201
 202 static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
 203         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
 204 };
 205
 206 static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
 207         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
 208 };
 209
 210 static int iwl4965_lq_sync_callback(struct iwl4965_priv *priv,
 211                                 struct iwl4965_cmd *cmd, struct sk_buff *skb)
 212 {
 213         /*We didn't cache the SKB; let the caller free it */
 214         return 1;
 215 }
 216
 217 static inline u8 iwl4965_rate_get_rate(u32 rate_n_flags)
 218 {
 219         return (u8)(rate_n_flags & 0xFF);
 220 }
 221
 222 static int rs_send_lq_cmd(struct iwl4965_priv *priv,
 223                           struct iwl4965_link_quality_cmd *lq, u8 flags)
 224 {
 225 #ifdef CONFIG_IWL4965_DEBUG
 226         int i;
 227 #endif
 228         struct iwl4965_host_cmd cmd = {
 229                 .id = REPLY_TX_LINK_QUALITY_CMD,
 230                 .len = sizeof(struct iwl4965_link_quality_cmd),
 231                 .meta.flags = flags,
 232                 .data = lq,
 233         };
 234
 235         if ((lq->sta_id == 0xFF) &&
 236             (priv->iw_mode == IEEE80211_IF_TYPE_IBSS))
 237                 return -EINVAL;
 238
 239         if (lq->sta_id == 0xFF)
 240                 lq->sta_id = IWL_AP_ID;
 241
 242         IWL_DEBUG_RATE("lq station id 0x%x\n", lq->sta_id);
 243         IWL_DEBUG_RATE("lq dta 0x%X 0x%X\n",
 244                        lq->general_params.single_stream_ant_msk,
 245                        lq->general_params.dual_stream_ant_msk);
 246 #ifdef CONFIG_IWL4965_DEBUG
 247         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
 248                 IWL_DEBUG_RATE("lq index %d 0x%X\n",
 249                                 i, lq->rs_table[i].rate_n_flags);
 250 #endif
 251
 252         if (flags & CMD_ASYNC)
 253                 cmd.meta.u.callback = iwl4965_lq_sync_callback;
 254
 255         if (iwl4965_is_associated(priv) && priv->assoc_station_added &&
 256             priv->lq_mngr.lq_ready)
 257                 return  iwl4965_send_cmd(priv, &cmd);
 258
 259         return 0;
 260 }
 261
 262 static void rs_rate_scale_clear_window(struct iwl4965_rate_scale_data *window)
 263 {
 264         window->data = 0;
 265         window->success_counter = 0;
 266         window->success_ratio = IWL_INVALID_VALUE;
 267         window->counter = 0;
 268         window->average_tpt = IWL_INVALID_VALUE;
 269         window->stamp = 0;
 270 }
 271
 272 /**
 273  * rs_collect_tx_data - Update the success/failure sliding window
 274  *
 275  * We keep a sliding window of the last 62 packets transmitted
 276  * at this rate.  window->data contains the bitmask of successful
 277  * packets.
 278  */
 279 static int rs_collect_tx_data(struct iwl4965_rate_scale_data *windows,
 280                               int scale_index, s32 tpt, u32 status)
 281 {
 282         struct iwl4965_rate_scale_data *window = NULL;
 283         u64 mask;
 284         u8 win_size = IWL_RATE_MAX_WINDOW;
 285         s32 fail_count;
 286
 287         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
 288                 return -EINVAL;
 289
 290         /* Select data for current tx bit rate */
 291         window = &(windows[scale_index]);
 292
 293         /*
 294          * Keep track of only the latest 62 tx frame attempts in this rate's
 295          * history window; anything older isn't really relevant any more.
 296          * If we have filled up the sliding window, drop the oldest attempt;
 297          * if the oldest attempt (highest bit in bitmap) shows "success",
 298          * subtract "1" from the success counter (this is the main reason
 299          * we keep these bitmaps!).
 300          */
 301         if (window->counter >= win_size) {
 302                 window->counter = win_size - 1;
 303                 mask = 1;
 304                 mask = (mask << (win_size - 1));
 305                 if ((window->data & mask)) {
 306                         window->data &= ~mask;
 307                         window->success_counter = window->success_counter - 1;
 308                 }
 309         }
 310
 311         /* Increment frames-attempted counter */
 312         window->counter = window->counter + 1;
 313
 314         /* Shift bitmap by one frame (throw away oldest history),
 315          * OR in "1", and increment "success" if this frame was successful. */
 316         mask = window->data;
 317         window->data = (mask << 1);
 318         if (status != 0) {
 319                 window->success_counter = window->success_counter + 1;
 320                 window->data |= 0x1;
 321         }
 322
 323         /* Calculate current success ratio, avoid divide-by-0! */
 324         if (window->counter > 0)
 325                 window->success_ratio = 128 * (100 * window->success_counter)
 326                                         / window->counter;
 327         else
 328                 window->success_ratio = IWL_INVALID_VALUE;
 329
 330         fail_count = window->counter - window->success_counter;
 331
 332         /* Calculate average throughput, if we have enough history. */
 333         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
 334             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
 335                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
 336         else
 337                 window->average_tpt = IWL_INVALID_VALUE;
 338
 339         /* Tag this window as having been updated */
 340         window->stamp = jiffies;
 341
 342         return 0;
 343 }
 344
 345 /*
 346  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
 347  */
 348 static void rs_mcs_from_tbl(struct iwl4965_rate *mcs_rate,
 349                            struct iwl4965_scale_tbl_info *tbl,
 350                            int index, u8 use_green)
 351 {
 352         if (is_legacy(tbl->lq_type)) {
 353                 mcs_rate->rate_n_flags = iwl4965_rates[index].plcp;
 354                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
 355                         mcs_rate->rate_n_flags |= RATE_MCS_CCK_MSK;
 356
 357         } else if (is_siso(tbl->lq_type)) {
 358                 if (index > IWL_LAST_OFDM_RATE)
 359                         index = IWL_LAST_OFDM_RATE;
 360                  mcs_rate->rate_n_flags = iwl4965_rates[index].plcp_siso |
 361                                           RATE_MCS_HT_MSK;
 362         } else {
 363                 if (index > IWL_LAST_OFDM_RATE)
 364                         index = IWL_LAST_OFDM_RATE;
 365                 mcs_rate->rate_n_flags = iwl4965_rates[index].plcp_mimo |
 366                                          RATE_MCS_HT_MSK;
 367         }
 368
 369         switch (tbl->antenna_type) {
 370         case ANT_BOTH:
 371                 mcs_rate->rate_n_flags |= RATE_MCS_ANT_AB_MSK;
 372                 break;
 373         case ANT_MAIN:
 374                 mcs_rate->rate_n_flags |= RATE_MCS_ANT_A_MSK;
 375                 break;
 376         case ANT_AUX:
 377                 mcs_rate->rate_n_flags |= RATE_MCS_ANT_B_MSK;
 378                 break;
 379         case ANT_NONE:
 380                 break;
 381         }
 382
 383         if (is_legacy(tbl->lq_type))
 384                 return;
 385
 386         if (tbl->is_fat) {
 387                 if (tbl->is_dup)
 388                         mcs_rate->rate_n_flags |= RATE_MCS_DUP_MSK;
 389                 else
 390                         mcs_rate->rate_n_flags |= RATE_MCS_FAT_MSK;
 391         }
 392         if (tbl->is_SGI)
 393                 mcs_rate->rate_n_flags |= RATE_MCS_SGI_MSK;
 394
 395         if (use_green) {
 396                 mcs_rate->rate_n_flags |= RATE_MCS_GF_MSK;
 397                 if (is_siso(tbl->lq_type))
 398                         mcs_rate->rate_n_flags &= ~RATE_MCS_SGI_MSK;
 399         }
 400 }
 401
 402 /*
 403  * Interpret uCode API's rate_n_flags format,
 404  * fill "search" or "active" tx mode table.
 405  */
 406 static int rs_get_tbl_info_from_mcs(const struct iwl4965_rate *mcs_rate,
 407                                     int phymode, struct iwl4965_scale_tbl_info *tbl,
 408                                     int *rate_idx)
 409 {
 410         int index;
 411         u32 ant_msk;
 412
 413         index = iwl4965_rate_index_from_plcp(mcs_rate->rate_n_flags);
 414
 415         if (index  == IWL_RATE_INVALID) {
 416                 *rate_idx = -1;
 417                 return -EINVAL;
 418         }
 419         tbl->is_SGI = 0;        /* default legacy setup */
 420         tbl->is_fat = 0;
 421         tbl->is_dup = 0;
 422         tbl->antenna_type = ANT_BOTH;   /* default MIMO setup */
 423
 424         /* legacy rate format */
 425         if (!(mcs_rate->rate_n_flags & RATE_MCS_HT_MSK)) {
 426                 ant_msk = (mcs_rate->rate_n_flags & RATE_MCS_ANT_AB_MSK);
 427
 428                 if (ant_msk == RATE_MCS_ANT_AB_MSK)
 429                         tbl->lq_type = LQ_NONE;
 430                 else {
 431
 432                         if (phymode == MODE_IEEE80211A)
 433                                 tbl->lq_type = LQ_A;
 434                         else
 435                                 tbl->lq_type = LQ_G;
 436
 437                         if (mcs_rate->rate_n_flags & RATE_MCS_ANT_A_MSK)
 438                                 tbl->antenna_type = ANT_MAIN;
 439                         else
 440                                 tbl->antenna_type = ANT_AUX;
 441                 }
 442                 *rate_idx = index;
 443
 444         /* HT rate format, SISO (might be 20 MHz legacy or 40 MHz fat width) */
 445         } else if (iwl4965_rate_get_rate(mcs_rate->rate_n_flags)
 446                                         <= IWL_RATE_SISO_60M_PLCP) {
 447                 tbl->lq_type = LQ_SISO;
 448
 449                 ant_msk = (mcs_rate->rate_n_flags & RATE_MCS_ANT_AB_MSK);
 450                 if (ant_msk == RATE_MCS_ANT_AB_MSK)
 451                         tbl->lq_type = LQ_NONE;
 452                 else {
 453                         if (mcs_rate->rate_n_flags & RATE_MCS_ANT_A_MSK)
 454                                 tbl->antenna_type = ANT_MAIN;
 455                         else
 456                                 tbl->antenna_type = ANT_AUX;
 457                 }
 458                 if (mcs_rate->rate_n_flags & RATE_MCS_SGI_MSK)
 459                         tbl->is_SGI = 1;
 460
 461                 if ((mcs_rate->rate_n_flags & RATE_MCS_FAT_MSK) ||
 462                     (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK))
 463                         tbl->is_fat = 1;
 464
 465                 if (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK)
 466                         tbl->is_dup = 1;
 467
 468                 *rate_idx = index;
 469
 470         /* HT rate format, MIMO (might be 20 MHz legacy or 40 MHz fat width) */
 471         } else {
 472                 tbl->lq_type = LQ_MIMO;
 473                 if (mcs_rate->rate_n_flags & RATE_MCS_SGI_MSK)
 474                         tbl->is_SGI = 1;
 475
 476                 if ((mcs_rate->rate_n_flags & RATE_MCS_FAT_MSK) ||
 477                     (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK))
 478                         tbl->is_fat = 1;
 479
 480                 if (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK)
 481                         tbl->is_dup = 1;
 482                 *rate_idx = index;
 483         }
 484         return 0;
 485 }
 486
 487 static inline void rs_toggle_antenna(struct iwl4965_rate *new_rate,
 488                                      struct iwl4965_scale_tbl_info *tbl)
 489 {
 490         if (tbl->antenna_type == ANT_AUX) {
 491                 tbl->antenna_type = ANT_MAIN;
 492                 new_rate->rate_n_flags &= ~RATE_MCS_ANT_B_MSK;
 493                 new_rate->rate_n_flags |= RATE_MCS_ANT_A_MSK;
 494         } else {
 495                 tbl->antenna_type = ANT_AUX;
 496                 new_rate->rate_n_flags &= ~RATE_MCS_ANT_A_MSK;
 497                 new_rate->rate_n_flags |= RATE_MCS_ANT_B_MSK;
 498         }
 499 }
 500
 501 static inline u8 rs_use_green(struct iwl4965_priv *priv,
 502                               struct ieee80211_conf *conf)
 503 {
 504 #ifdef CONFIG_IWL4965_HT
 505         return ((conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
 506                 priv->current_ht_config.is_green_field &&
 507                 !priv->current_ht_config.non_GF_STA_present);
 508 #endif  /* CONFIG_IWL4965_HT */
 509         return 0;
 510 }
 511
 512 /**
 513  * rs_get_supported_rates - get the available rates
 514  *
 515  * if management frame or broadcast frame only return
 516  * basic available rates.
 517  *
 518  */
 519 static void rs_get_supported_rates(struct iwl4965_lq_sta *lq_sta,
 520                                    struct ieee80211_hdr *hdr,
 521                                    enum iwl4965_table_type rate_type,
 522                                    u16 *data_rate)
 523 {
 524         if (is_legacy(rate_type))
 525                 *data_rate = lq_sta->active_rate;
 526         else {
 527                 if (is_siso(rate_type))
 528                         *data_rate = lq_sta->active_siso_rate;
 529                 else
 530                         *data_rate = lq_sta->active_mimo_rate;
 531         }
 532
 533         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
 534             lq_sta->active_rate_basic) {
 535                 *data_rate = lq_sta->active_rate_basic;
 536         }
 537 }
 538
 539 static u16 rs_get_adjacent_rate(u8 index, u16 rate_mask, int rate_type)
 540 {
 541         u8 high = IWL_RATE_INVALID;
 542         u8 low = IWL_RATE_INVALID;
 543
 544         /* 802.11A or ht walks to the next literal adjacent rate in
 545          * the rate table */
 546         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
 547                 int i;
 548                 u32 mask;
 549
 550                 /* Find the previous rate that is in the rate mask */
 551                 i = index - 1;
 552                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 553                         if (rate_mask & mask) {
 554                                 low = i;
 555                                 break;
 556                         }
 557                 }
 558
 559                 /* Find the next rate that is in the rate mask */
 560                 i = index + 1;
 561                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 562                         if (rate_mask & mask) {
 563                                 high = i;
 564                                 break;
 565                         }
 566                 }
 567
 568                 return (high << 8) | low;
 569         }
 570
 571         low = index;
 572         while (low != IWL_RATE_INVALID) {
 573                 low = iwl4965_rates[low].prev_rs;
 574                 if (low == IWL_RATE_INVALID)
 575                         break;
 576                 if (rate_mask & (1 << low))
 577                         break;
 578                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
 579         }
 580
 581         high = index;
 582         while (high != IWL_RATE_INVALID) {
 583                 high = iwl4965_rates[high].next_rs;
 584                 if (high == IWL_RATE_INVALID)
 585                         break;
 586                 if (rate_mask & (1 << high))
 587                         break;
 588                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
 589         }
 590
 591         return (high << 8) | low;
 592 }
 593
 594 static void rs_get_lower_rate(struct iwl4965_lq_sta *lq_sta,
 595                              struct iwl4965_scale_tbl_info *tbl, u8 scale_index,
 596                              u8 ht_possible, struct iwl4965_rate *mcs_rate)
 597 {
 598         s32 low;
 599         u16 rate_mask;
 600         u16 high_low;
 601         u8 switch_to_legacy = 0;
 602         u8 is_green = lq_sta->is_green;
 603
 604         /* check if we need to switch from HT to legacy rates.
 605          * assumption is that mandatory rates (1Mbps or 6Mbps)
 606          * are always supported (spec demand) */
 607         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
 608                 switch_to_legacy = 1;
 609                 scale_index = rs_ht_to_legacy[scale_index];
 610                 if (lq_sta->phymode == MODE_IEEE80211A)
 611                         tbl->lq_type = LQ_A;
 612                 else
 613                         tbl->lq_type = LQ_G;
 614
 615                 if ((tbl->antenna_type == ANT_BOTH) ||
 616                     (tbl->antenna_type == ANT_NONE))
 617                         tbl->antenna_type = ANT_MAIN;
 618
 619                 tbl->is_fat = 0;
 620                 tbl->is_SGI = 0;
 621         }
 622
 623         rs_get_supported_rates(lq_sta, NULL, tbl->lq_type, &rate_mask);
 624
 625         /* Mask with station rate restriction */
 626         if (is_legacy(tbl->lq_type)) {
 627                 /* supp_rates has no CCK bits in A mode */
 628                 if (lq_sta->phymode == (u8) MODE_IEEE80211A)
 629                         rate_mask  = (u16)(rate_mask &
 630                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
 631                 else
 632                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
 633         }
 634
 635         /* If we switched from HT to legacy, check current rate */
 636         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
 637                 rs_mcs_from_tbl(mcs_rate, tbl, scale_index, is_green);
 638                 return;
 639         }
 640
 641         high_low = rs_get_adjacent_rate(scale_index, rate_mask, tbl->lq_type);
 642         low = high_low & 0xff;
 643
 644         if (low != IWL_RATE_INVALID)
 645                 rs_mcs_from_tbl(mcs_rate, tbl, low, is_green);
 646         else
 647                 rs_mcs_from_tbl(mcs_rate, tbl, scale_index, is_green);
 648 }
 649
 650 /*
 651  * mac80211 sends us Tx status
 652  */
 653 static void rs_tx_status(void *priv_rate, struct net_device *dev,
 654                          struct sk_buff *skb,
 655                          struct ieee80211_tx_status *tx_resp)
 656 {
 657         int status;
 658         u8 retries;
 659         int rs_index, index = 0;
 660         struct iwl4965_lq_sta *lq_sta;
 661         struct iwl4965_link_quality_cmd *table;
 662         struct sta_info *sta;
 663         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 664         struct iwl4965_priv *priv = (struct iwl4965_priv *)priv_rate;
 665         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 666         struct iwl4965_rate_scale_data *window = NULL;
 667         struct iwl4965_rate_scale_data *search_win = NULL;
 668         struct iwl4965_rate tx_mcs;
 669         struct iwl4965_scale_tbl_info tbl_type;
 670         struct iwl4965_scale_tbl_info *curr_tbl, *search_tbl;
 671         u8 active_index = 0;
 672         u16 fc = le16_to_cpu(hdr->frame_control);
 673         s32 tpt = 0;
 674
 675         IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
 676
 677         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1))
 678                 return;
 679
 680         retries = tx_resp->retry_count;
 681
 682         if (retries > 15)
 683                 retries = 15;
 684
 685
 686         sta = sta_info_get(local, hdr->addr1);
 687
 688         if (!sta || !sta->rate_ctrl_priv) {
 689                 if (sta)
 690                         sta_info_put(sta);
 691                 return;
 692         }
 693
 694         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
 695
 696         if (!priv->lq_mngr.lq_ready)
 697                 return;
 698
 699         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
 700             !lq_sta->ibss_sta_added)
 701                 return;
 702
 703         table = &lq_sta->lq;
 704         active_index = lq_sta->active_tbl;
 705
 706         /* Get mac80211 antenna info */
 707         lq_sta->antenna =
 708                 (lq_sta->valid_antenna & local->hw.conf.antenna_sel_tx);
 709         if (!lq_sta->antenna)
 710                 lq_sta->antenna = lq_sta->valid_antenna;
 711
 712         /* Ignore mac80211 antenna info for now */
 713         lq_sta->antenna = lq_sta->valid_antenna;
 714
 715         curr_tbl = &(lq_sta->lq_info[active_index]);
 716         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
 717         window = (struct iwl4965_rate_scale_data *)
 718             &(curr_tbl->win[0]);
 719         search_win = (struct iwl4965_rate_scale_data *)
 720             &(search_tbl->win[0]);
 721
 722         tx_mcs.rate_n_flags = tx_resp->control.tx_rate;
 723
 724         rs_get_tbl_info_from_mcs(&tx_mcs, priv->phymode,
 725                                   &tbl_type, &rs_index);
 726         if ((rs_index < 0) || (rs_index >= IWL_RATE_COUNT)) {
 727                 IWL_DEBUG_RATE("bad rate index at: %d rate 0x%X\n",
 728                              rs_index, tx_mcs.rate_n_flags);
 729                 sta_info_put(sta);
 730                 return;
 731         }
 732
 733         /*
 734          * Ignore this Tx frame response if its initial rate doesn't match
 735          * that of latest Link Quality command.  There may be stragglers
 736          * from a previous Link Quality command, but we're no longer interested
 737          * in those; they're either from the "active" mode while we're trying
 738          * to check "search" mode, or a prior "search" mode after we've moved
 739          * to a new "search" mode (which might become the new "active" mode).
 740          */
 741         if (retries &&
 742             (tx_mcs.rate_n_flags !=
 743                                 le32_to_cpu(table->rs_table[0].rate_n_flags))) {
 744                 IWL_DEBUG_RATE("initial rate does not match 0x%x 0x%x\n",
 745                                 tx_mcs.rate_n_flags,
 746                                 le32_to_cpu(table->rs_table[0].rate_n_flags));
 747                 sta_info_put(sta);
 748                 return;
 749         }
 750
 751         /* Update frame history window with "failure" for each Tx retry. */
 752         while (retries) {
 753                 /* Look up the rate and other info used for each tx attempt.
 754                  * Each tx attempt steps one entry deeper in the rate table. */
 755                 tx_mcs.rate_n_flags =
 756                     le32_to_cpu(table->rs_table[index].rate_n_flags);
 757                 rs_get_tbl_info_from_mcs(&tx_mcs, priv->phymode,
 758                                           &tbl_type, &rs_index);
 759
 760                 /* If type matches "search" table,
 761                  * add failure to "search" history */
 762                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
 763                     (tbl_type.antenna_type == search_tbl->antenna_type) &&
 764                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
 765                         if (search_tbl->expected_tpt)
 766                                 tpt = search_tbl->expected_tpt[rs_index];
 767                         else
 768                                 tpt = 0;
 769                         rs_collect_tx_data(search_win, rs_index, tpt, 0);
 770
 771                 /* Else if type matches "current/active" table,
 772                  * add failure to "current/active" history */
 773                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 774                            (tbl_type.antenna_type == curr_tbl->antenna_type) &&
 775                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 776                         if (curr_tbl->expected_tpt)
 777                                 tpt = curr_tbl->expected_tpt[rs_index];
 778                         else
 779                                 tpt = 0;
 780                         rs_collect_tx_data(window, rs_index, tpt, 0);
 781                 }
 782
 783                 /* If not searching for a new mode, increment failed counter
 784                  * ... this helps determine when to start searching again */
 785                 if (lq_sta->stay_in_tbl)
 786                         lq_sta->total_failed++;
 787                 --retries;
 788                 index++;
 789
 790         }
 791
 792         /*
 793          * Find (by rate) the history window to update with final Tx attempt;
 794          * if Tx was successful first try, use original rate,
 795          * else look up the rate that was, finally, successful.
 796          */
 797         if (!tx_resp->retry_count)
 798                 tx_mcs.rate_n_flags = tx_resp->control.tx_rate;
 799         else
 800                 tx_mcs.rate_n_flags =
 801                         le32_to_cpu(table->rs_table[index].rate_n_flags);
 802
 803         rs_get_tbl_info_from_mcs(&tx_mcs, priv->phymode,
 804                                   &tbl_type, &rs_index);
 805
 806         /* Update frame history window with "success" if Tx got ACKed ... */
 807         if (tx_resp->flags & IEEE80211_TX_STATUS_ACK)
 808                 status = 1;
 809         else
 810                 status = 0;
 811
 812         /* If type matches "search" table,
 813          * add final tx status to "search" history */
 814         if ((tbl_type.lq_type == search_tbl->lq_type) &&
 815             (tbl_type.antenna_type == search_tbl->antenna_type) &&
 816             (tbl_type.is_SGI == search_tbl->is_SGI)) {
 817                 if (search_tbl->expected_tpt)
 818                         tpt = search_tbl->expected_tpt[rs_index];
 819                 else
 820                         tpt = 0;
 821                 rs_collect_tx_data(search_win,
 822                                     rs_index, tpt, status);
 823
 824         /* Else if type matches "current/active" table,
 825          * add final tx status to "current/active" history */
 826         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
 827                    (tbl_type.antenna_type == curr_tbl->antenna_type) &&
 828                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
 829                 if (curr_tbl->expected_tpt)
 830                         tpt = curr_tbl->expected_tpt[rs_index];
 831                 else
 832                         tpt = 0;
 833                 rs_collect_tx_data(window, rs_index, tpt, status);
 834         }
 835
 836         /* If not searching for new mode, increment success/failed counter
 837          * ... these help determine when to start searching again */
 838         if (lq_sta->stay_in_tbl) {
 839                 if (status)
 840                         lq_sta->total_success++;
 841                 else
 842                         lq_sta->total_failed++;
 843         }
 844
 845         /* See if there's a better rate or modulation mode to try. */
 846         rs_rate_scale_perform(priv, dev, hdr, sta);
 847         sta_info_put(sta);
 848         return;
 849 }
 850
 851 static u8 rs_is_ant_connected(u8 valid_antenna,
 852                               enum iwl4965_antenna_type antenna_type)
 853 {
 854         if (antenna_type == ANT_AUX)
 855                 return ((valid_antenna & 0x2) ? 1:0);
 856         else if (antenna_type == ANT_MAIN)
 857                 return ((valid_antenna & 0x1) ? 1:0);
 858         else if (antenna_type == ANT_BOTH)
 859                 return ((valid_antenna & 0x3) == 0x3);
 860
 861         return 1;
 862 }
 863
 864 static u8 rs_is_other_ant_connected(u8 valid_antenna,
 865                                     enum iwl4965_antenna_type antenna_type)
 866 {
 867         if (antenna_type == ANT_AUX)
 868                 return rs_is_ant_connected(valid_antenna, ANT_MAIN);
 869         else
 870                 return rs_is_ant_connected(valid_antenna, ANT_AUX);
 871
 872         return 0;
 873 }
 874
 875 /*
 876  * Begin a period of staying with a selected modulation mode.
 877  * Set "stay_in_tbl" flag to prevent any mode switches.
 878  * Set frame tx success limits according to legacy vs. high-throughput,
 879  * and reset overall (spanning all rates) tx success history statistics.
 880  * These control how long we stay using same modulation mode before
 881  * searching for a new mode.
 882  */
 883 static void rs_set_stay_in_table(u8 is_legacy,
 884                                  struct iwl4965_lq_sta *lq_sta)
 885 {
 886         IWL_DEBUG_HT("we are staying in the same table\n");
 887         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
 888         if (is_legacy) {
 889                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
 890                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
 891                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
 892         } else {
 893                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
 894                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
 895                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
 896         }
 897         lq_sta->table_count = 0;
 898         lq_sta->total_failed = 0;
 899         lq_sta->total_success = 0;
 900 }
 901
 902 /*
 903  * Find correct throughput table for given mode of modulation
 904  */
 905 static void rs_get_expected_tpt_table(struct iwl4965_lq_sta *lq_sta,
 906                                       struct iwl4965_scale_tbl_info *tbl)
 907 {
 908         if (is_legacy(tbl->lq_type)) {
 909                 if (!is_a_band(tbl->lq_type))
 910                         tbl->expected_tpt = expected_tpt_G;
 911                 else
 912                         tbl->expected_tpt = expected_tpt_A;
 913         } else if (is_siso(tbl->lq_type)) {
 914                 if (tbl->is_fat && !lq_sta->is_dup)
 915                         if (tbl->is_SGI)
 916                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
 917                         else
 918                                 tbl->expected_tpt = expected_tpt_siso40MHz;
 919                 else if (tbl->is_SGI)
 920                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
 921                 else
 922                         tbl->expected_tpt = expected_tpt_siso20MHz;
 923
 924         } else if (is_mimo(tbl->lq_type)) {
 925                 if (tbl->is_fat && !lq_sta->is_dup)
 926                         if (tbl->is_SGI)
 927                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
 928                         else
 929                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
 930                 else if (tbl->is_SGI)
 931                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
 932                 else
 933                         tbl->expected_tpt = expected_tpt_mimo20MHz;
 934         } else
 935                 tbl->expected_tpt = expected_tpt_G;
 936 }
 937
 938 #ifdef CONFIG_IWL4965_HT
 939 /*
 940  * Find starting rate for new "search" high-throughput mode of modulation.
 941  * Goal is to find lowest expected rate (under perfect conditions) that is
 942  * above the current measured throughput of "active" mode, to give new mode
 943  * a fair chance to prove itself without too many challenges.
 944  *
 945  * This gets called when transitioning to more aggressive modulation
 946  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
 947  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
 948  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
 949  * bit rate will typically need to increase, but not if performance was bad.
 950  */
 951 static s32 rs_get_best_rate(struct iwl4965_priv *priv,
 952                             struct iwl4965_lq_sta *lq_sta,
 953                             struct iwl4965_scale_tbl_info *tbl, /* "search" */
 954                             u16 rate_mask, s8 index, s8 rate)
 955 {
 956         /* "active" values */
 957         struct iwl4965_scale_tbl_info *active_tbl =
 958             &(lq_sta->lq_info[lq_sta->active_tbl]);
 959         s32 active_sr = active_tbl->win[index].success_ratio;
 960         s32 active_tpt = active_tbl->expected_tpt[index];
 961
 962         /* expected "search" throughput */
 963         s32 *tpt_tbl = tbl->expected_tpt;
 964
 965         s32 new_rate, high, low, start_hi;
 966         u16 high_low;
 967
 968         new_rate = high = low = start_hi = IWL_RATE_INVALID;
 969
 970         for (; ;) {
 971                 high_low = rs_get_adjacent_rate(rate, rate_mask, tbl->lq_type);
 972
 973                 low = high_low & 0xff;
 974                 high = (high_low >> 8) & 0xff;
 975
 976                 /*
 977                  * Lower the "search" bit rate, to give new "search" mode
 978                  * approximately the same throughput as "active" if:
 979                  *
 980                  * 1) "Active" mode has been working modestly well (but not
 981                  *    great), and expected "search" throughput (under perfect
 982                  *    conditions) at candidate rate is above the actual
 983                  *    measured "active" throughput (but less than expected
 984                  *    "active" throughput under perfect conditions).
 985                  * OR
 986                  * 2) "Active" mode has been working perfectly or very well
 987                  *    and expected "search" throughput (under perfect
 988                  *    conditions) at candidate rate is above expected
 989                  *    "active" throughput (under perfect conditions).
 990                  */
 991                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
 992                      ((active_sr > IWL_RATE_DECREASE_TH) &&
 993                       (active_sr <= IWL_RATE_HIGH_TH) &&
 994                       (tpt_tbl[rate] <= active_tpt))) ||
 995                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
 996                      (tpt_tbl[rate] > active_tpt))) {
 997
 998                         /* (2nd or later pass)
 999                          * If we've already tried to raise the rate, and are
1000                          * now trying to lower it, use the higher rate. */
1001                         if (start_hi != IWL_RATE_INVALID) {
1002                                 new_rate = start_hi;
1003                                 break;
1004                         }
1005
1006                         new_rate = rate;
1007
1008                         /* Loop again with lower rate */
1009                         if (low != IWL_RATE_INVALID)
1010                                 rate = low;
1011
1012                         /* Lower rate not available, use the original */
1013                         else
1014                                 break;
1015
1016                 /* Else try to raise the "search" rate to match "active" */
1017                 } else {
1018                         /* (2nd or later pass)
1019                          * If we've already tried to lower the rate, and are
1020                          * now trying to raise it, use the lower rate. */
1021                         if (new_rate != IWL_RATE_INVALID)
1022                                 break;
1023
1024                         /* Loop again with higher rate */
1025                         else if (high != IWL_RATE_INVALID) {
1026                                 start_hi = high;
1027                                 rate = high;
1028
1029                         /* Higher rate not available, use the original */
1030                         } else {
1031                                 new_rate = rate;
1032                                 break;
1033                         }
1034                 }
1035         }
1036
1037         return new_rate;
1038 }
1039 #endif                          /* CONFIG_IWL4965_HT */
1040
1041 static inline u8 rs_is_both_ant_supp(u8 valid_antenna)
1042 {
1043         return (rs_is_ant_connected(valid_antenna, ANT_BOTH));
1044 }
1045
1046 /*
1047  * Set up search table for MIMO
1048  */
1049 static int rs_switch_to_mimo(struct iwl4965_priv *priv,
1050                              struct iwl4965_lq_sta *lq_sta,
1051                              struct ieee80211_conf *conf,
1052                              struct sta_info *sta,
1053                              struct iwl4965_scale_tbl_info *tbl, int index)
1054 {
1055 #ifdef CONFIG_IWL4965_HT
1056         u16 rate_mask;
1057         s32 rate;
1058         s8 is_green = lq_sta->is_green;
1059
1060         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1061             !sta->ht_info.ht_supported)
1062                 return -1;
1063
1064         IWL_DEBUG_HT("LQ: try to switch to MIMO\n");
1065         tbl->lq_type = LQ_MIMO;
1066         rs_get_supported_rates(lq_sta, NULL, tbl->lq_type,
1067                                 &rate_mask);
1068
1069         if (priv->current_ht_config.tx_mimo_ps_mode == IWL_MIMO_PS_STATIC)
1070                 return -1;
1071
1072         /* Need both Tx chains/antennas to support MIMO */
1073         if (!rs_is_both_ant_supp(lq_sta->antenna))
1074                 return -1;
1075
1076         tbl->is_dup = lq_sta->is_dup;
1077         tbl->action = 0;
1078         if (priv->current_ht_config.supported_chan_width
1079             == IWL_CHANNEL_WIDTH_40MHZ)
1080                 tbl->is_fat = 1;
1081         else
1082                 tbl->is_fat = 0;
1083
1084         if (tbl->is_fat) {
1085                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1086                         tbl->is_SGI = 1;
1087                 else
1088                         tbl->is_SGI = 0;
1089         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1090                 tbl->is_SGI = 1;
1091         else
1092                 tbl->is_SGI = 0;
1093
1094         rs_get_expected_tpt_table(lq_sta, tbl);
1095
1096         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index, index);
1097
1098         IWL_DEBUG_HT("LQ: MIMO best rate %d mask %X\n", rate, rate_mask);
1099         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask))
1100                 return -1;
1101         rs_mcs_from_tbl(&tbl->current_rate, tbl, rate, is_green);
1102
1103         IWL_DEBUG_HT("LQ: Switch to new mcs %X index is green %X\n",
1104                      tbl->current_rate.rate_n_flags, is_green);
1105         return 0;
1106 #else
1107         return -1;
1108 #endif                          /*CONFIG_IWL4965_HT */
1109 }
1110
1111 /*
1112  * Set up search table for SISO
1113  */
1114 static int rs_switch_to_siso(struct iwl4965_priv *priv,
1115                              struct iwl4965_lq_sta *lq_sta,
1116                              struct ieee80211_conf *conf,
1117                              struct sta_info *sta,
1118                              struct iwl4965_scale_tbl_info *tbl, int index)
1119 {
1120 #ifdef CONFIG_IWL4965_HT
1121         u16 rate_mask;
1122         u8 is_green = lq_sta->is_green;
1123         s32 rate;
1124
1125         IWL_DEBUG_HT("LQ: try to switch to SISO\n");
1126         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1127             !sta->ht_info.ht_supported)
1128                 return -1;
1129
1130         tbl->is_dup = lq_sta->is_dup;
1131         tbl->lq_type = LQ_SISO;
1132         tbl->action = 0;
1133         rs_get_supported_rates(lq_sta, NULL, tbl->lq_type,
1134                                 &rate_mask);
1135
1136         if (priv->current_ht_config.supported_chan_width
1137             == IWL_CHANNEL_WIDTH_40MHZ)
1138                 tbl->is_fat = 1;
1139         else
1140                 tbl->is_fat = 0;
1141
1142         if (tbl->is_fat) {
1143                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1144                         tbl->is_SGI = 1;
1145                 else
1146                         tbl->is_SGI = 0;
1147         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1148                 tbl->is_SGI = 1;
1149         else
1150                 tbl->is_SGI = 0;
1151
1152         if (is_green)
1153                 tbl->is_SGI = 0;
1154
1155         rs_get_expected_tpt_table(lq_sta, tbl);
1156         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index, index);
1157
1158         IWL_DEBUG_HT("LQ: get best rate %d mask %X\n", rate, rate_mask);
1159         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1160                 IWL_DEBUG_HT("can not switch with index %d rate mask %x\n",
1161                              rate, rate_mask);
1162                 return -1;
1163         }
1164         rs_mcs_from_tbl(&tbl->current_rate, tbl, rate, is_green);
1165         IWL_DEBUG_HT("LQ: Switch to new mcs %X index is green %X\n",
1166                      tbl->current_rate.rate_n_flags, is_green);
1167         return 0;
1168 #else
1169         return -1;
1170
1171 #endif                          /*CONFIG_IWL4965_HT */
1172 }
1173
1174 /*
1175  * Try to switch to new modulation mode from legacy
1176  */
1177 static int rs_move_legacy_other(struct iwl4965_priv *priv,
1178                                 struct iwl4965_lq_sta *lq_sta,
1179                                 struct ieee80211_conf *conf,
1180                                 struct sta_info *sta,
1181                                 int index)
1182 {
1183         int ret = 0;
1184         struct iwl4965_scale_tbl_info *tbl =
1185             &(lq_sta->lq_info[lq_sta->active_tbl]);
1186         struct iwl4965_scale_tbl_info *search_tbl =
1187             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1188         struct iwl4965_rate_scale_data *window = &(tbl->win[index]);
1189         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1190                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1191         u8 start_action = tbl->action;
1192
1193         for (; ;) {
1194                 switch (tbl->action) {
1195                 case IWL_LEGACY_SWITCH_ANTENNA:
1196                         IWL_DEBUG_HT("LQ Legacy switch Antenna\n");
1197
1198                         search_tbl->lq_type = LQ_NONE;
1199                         lq_sta->action_counter++;
1200
1201                         /* Don't change antenna if success has been great */
1202                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1203                                 break;
1204
1205                         /* Don't change antenna if other one is not connected */
1206                         if (!rs_is_other_ant_connected(lq_sta->antenna,
1207                                                         tbl->antenna_type))
1208                                 break;
1209
1210                         /* Set up search table to try other antenna */
1211                         memcpy(search_tbl, tbl, sz);
1212
1213                         rs_toggle_antenna(&(search_tbl->current_rate),
1214                                            search_tbl);
1215                         rs_get_expected_tpt_table(lq_sta, search_tbl);
1216                         lq_sta->search_better_tbl = 1;
1217                         goto out;
1218
1219                 case IWL_LEGACY_SWITCH_SISO:
1220                         IWL_DEBUG_HT("LQ: Legacy switch to SISO\n");
1221
1222                         /* Set up search table to try SISO */
1223                         memcpy(search_tbl, tbl, sz);
1224                         search_tbl->lq_type = LQ_SISO;
1225                         search_tbl->is_SGI = 0;
1226                         search_tbl->is_fat = 0;
1227                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1228                                                  search_tbl, index);
1229                         if (!ret) {
1230                                 lq_sta->search_better_tbl = 1;
1231                                 lq_sta->action_counter = 0;
1232                                 goto out;
1233                         }
1234
1235                         break;
1236                 case IWL_LEGACY_SWITCH_MIMO:
1237                         IWL_DEBUG_HT("LQ: Legacy switch MIMO\n");
1238
1239                         /* Set up search table to try MIMO */
1240                         memcpy(search_tbl, tbl, sz);
1241                         search_tbl->lq_type = LQ_MIMO;
1242                         search_tbl->is_SGI = 0;
1243                         search_tbl->is_fat = 0;
1244                         search_tbl->antenna_type = ANT_BOTH;
1245                         ret = rs_switch_to_mimo(priv, lq_sta, conf, sta,
1246                                                  search_tbl, index);
1247                         if (!ret) {
1248                                 lq_sta->search_better_tbl = 1;
1249                                 lq_sta->action_counter = 0;
1250                                 goto out;
1251                         }
1252                         break;
1253                 }
1254                 tbl->action++;
1255                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO)
1256                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA;
1257
1258                 if (tbl->action == start_action)
1259                         break;
1260
1261         }
1262         return 0;
1263
1264  out:
1265         tbl->action++;
1266         if (tbl->action > IWL_LEGACY_SWITCH_MIMO)
1267                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA;
1268         return 0;
1269
1270 }
1271
1272 /*
1273  * Try to switch to new modulation mode from SISO
1274  */
1275 static int rs_move_siso_to_other(struct iwl4965_priv *priv,
1276                                  struct iwl4965_lq_sta *lq_sta,
1277                                  struct ieee80211_conf *conf,
1278                                  struct sta_info *sta,
1279                                  int index)
1280 {
1281         int ret;
1282         u8 is_green = lq_sta->is_green;
1283         struct iwl4965_scale_tbl_info *tbl =
1284             &(lq_sta->lq_info[lq_sta->active_tbl]);
1285         struct iwl4965_scale_tbl_info *search_tbl =
1286             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1287         struct iwl4965_rate_scale_data *window = &(tbl->win[index]);
1288         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1289                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1290         u8 start_action = tbl->action;
1291
1292         for (;;) {
1293                 lq_sta->action_counter++;
1294                 switch (tbl->action) {
1295                 case IWL_SISO_SWITCH_ANTENNA:
1296                         IWL_DEBUG_HT("LQ: SISO SWITCH ANTENNA SISO\n");
1297                         search_tbl->lq_type = LQ_NONE;
1298                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1299                                 break;
1300                         if (!rs_is_other_ant_connected(lq_sta->antenna,
1301                                                        tbl->antenna_type))
1302                                 break;
1303
1304                         memcpy(search_tbl, tbl, sz);
1305                         search_tbl->action = IWL_SISO_SWITCH_MIMO;
1306                         rs_toggle_antenna(&(search_tbl->current_rate),
1307                                            search_tbl);
1308                         lq_sta->search_better_tbl = 1;
1309
1310                         goto out;
1311
1312                 case IWL_SISO_SWITCH_MIMO:
1313                         IWL_DEBUG_HT("LQ: SISO SWITCH TO MIMO FROM SISO\n");
1314                         memcpy(search_tbl, tbl, sz);
1315                         search_tbl->lq_type = LQ_MIMO;
1316                         search_tbl->is_SGI = 0;
1317                         search_tbl->is_fat = 0;
1318                         search_tbl->antenna_type = ANT_BOTH;
1319                         ret = rs_switch_to_mimo(priv, lq_sta, conf, sta,
1320                                                  search_tbl, index);
1321                         if (!ret) {
1322                                 lq_sta->search_better_tbl = 1;
1323                                 goto out;
1324                         }
1325                         break;
1326                 case IWL_SISO_SWITCH_GI:
1327                         IWL_DEBUG_HT("LQ: SISO SWITCH TO GI\n");
1328                         memcpy(search_tbl, tbl, sz);
1329                         search_tbl->action = 0;
1330                         if (search_tbl->is_SGI)
1331                                 search_tbl->is_SGI = 0;
1332                         else if (!is_green)
1333                                 search_tbl->is_SGI = 1;
1334                         else
1335                                 break;
1336                         lq_sta->search_better_tbl = 1;
1337                         if ((tbl->lq_type == LQ_SISO) &&
1338                             (tbl->is_SGI)) {
1339                                 s32 tpt = lq_sta->last_tpt / 100;
1340                                 if (((!tbl->is_fat) &&
1341                                      (tpt >= expected_tpt_siso20MHz[index])) ||
1342                                     ((tbl->is_fat) &&
1343                                      (tpt >= expected_tpt_siso40MHz[index])))
1344                                         lq_sta->search_better_tbl = 0;
1345                         }
1346                         rs_get_expected_tpt_table(lq_sta, search_tbl);
1347                         rs_mcs_from_tbl(&search_tbl->current_rate,
1348                                              search_tbl, index, is_green);
1349                         goto out;
1350                 }
1351                 tbl->action++;
1352                 if (tbl->action > IWL_SISO_SWITCH_GI)
1353                         tbl->action = IWL_SISO_SWITCH_ANTENNA;
1354
1355                 if (tbl->action == start_action)
1356                         break;
1357         }
1358         return 0;
1359
1360  out:
1361         tbl->action++;
1362         if (tbl->action > IWL_SISO_SWITCH_GI)
1363                 tbl->action = IWL_SISO_SWITCH_ANTENNA;
1364         return 0;
1365 }
1366
1367 /*
1368  * Try to switch to new modulation mode from MIMO
1369  */
1370 static int rs_move_mimo_to_other(struct iwl4965_priv *priv,
1371                                  struct iwl4965_lq_sta *lq_sta,
1372                                  struct ieee80211_conf *conf,
1373                                  struct sta_info *sta,
1374                                  int index)
1375 {
1376         int ret;
1377         s8 is_green = lq_sta->is_green;
1378         struct iwl4965_scale_tbl_info *tbl =
1379             &(lq_sta->lq_info[lq_sta->active_tbl]);
1380         struct iwl4965_scale_tbl_info *search_tbl =
1381             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1382         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1383                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1384         u8 start_action = tbl->action;
1385
1386         for (;;) {
1387                 lq_sta->action_counter++;
1388                 switch (tbl->action) {
1389                 case IWL_MIMO_SWITCH_ANTENNA_A:
1390                 case IWL_MIMO_SWITCH_ANTENNA_B:
1391                         IWL_DEBUG_HT("LQ: MIMO SWITCH TO SISO\n");
1392
1393                         /* Set up new search table for SISO */
1394                         memcpy(search_tbl, tbl, sz);
1395                         search_tbl->lq_type = LQ_SISO;
1396                         search_tbl->is_SGI = 0;
1397                         search_tbl->is_fat = 0;
1398                         if (tbl->action == IWL_MIMO_SWITCH_ANTENNA_A)
1399                                 search_tbl->antenna_type = ANT_MAIN;
1400                         else
1401                                 search_tbl->antenna_type = ANT_AUX;
1402
1403                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1404                                                  search_tbl, index);
1405                         if (!ret) {
1406                                 lq_sta->search_better_tbl = 1;
1407                                 goto out;
1408                         }
1409                         break;
1410
1411                 case IWL_MIMO_SWITCH_GI:
1412                         IWL_DEBUG_HT("LQ: MIMO SWITCH TO GI\n");
1413
1414                         /* Set up new search table for MIMO */
1415                         memcpy(search_tbl, tbl, sz);
1416                         search_tbl->lq_type = LQ_MIMO;
1417                         search_tbl->antenna_type = ANT_BOTH;
1418                         search_tbl->action = 0;
1419                         if (search_tbl->is_SGI)
1420                                 search_tbl->is_SGI = 0;
1421                         else
1422                                 search_tbl->is_SGI = 1;
1423                         lq_sta->search_better_tbl = 1;
1424
1425                         /*
1426                          * If active table already uses the fastest possible
1427                          * modulation (dual stream with short guard interval),
1428                          * and it's working well, there's no need to look
1429                          * for a better type of modulation!
1430                          */
1431                         if ((tbl->lq_type == LQ_MIMO) &&
1432                             (tbl->is_SGI)) {
1433                                 s32 tpt = lq_sta->last_tpt / 100;
1434                                 if (((!tbl->is_fat) &&
1435                                      (tpt >= expected_tpt_mimo20MHz[index])) ||
1436                                     ((tbl->is_fat) &&
1437                                      (tpt >= expected_tpt_mimo40MHz[index])))
1438                                         lq_sta->search_better_tbl = 0;
1439                         }
1440                         rs_get_expected_tpt_table(lq_sta, search_tbl);
1441                         rs_mcs_from_tbl(&search_tbl->current_rate,
1442                                              search_tbl, index, is_green);
1443                         goto out;
1444
1445                 }
1446                 tbl->action++;
1447                 if (tbl->action > IWL_MIMO_SWITCH_GI)
1448                         tbl->action = IWL_MIMO_SWITCH_ANTENNA_A;
1449
1450                 if (tbl->action == start_action)
1451                         break;
1452         }
1453
1454         return 0;
1455  out:
1456         tbl->action++;
1457         if (tbl->action > IWL_MIMO_SWITCH_GI)
1458                 tbl->action = IWL_MIMO_SWITCH_ANTENNA_A;
1459         return 0;
1460
1461 }
1462
1463 /*
1464  * Check whether we should continue using same modulation mode, or
1465  * begin search for a new mode, based on:
1466  * 1) # tx successes or failures while using this mode
1467  * 2) # times calling this function
1468  * 3) elapsed time in this mode (not used, for now)
1469  */
1470 static void rs_stay_in_table(struct iwl4965_lq_sta *lq_sta)
1471 {
1472         struct iwl4965_scale_tbl_info *tbl;
1473         int i;
1474         int active_tbl;
1475         int flush_interval_passed = 0;
1476
1477         active_tbl = lq_sta->active_tbl;
1478
1479         tbl = &(lq_sta->lq_info[active_tbl]);
1480
1481         /* If we've been disallowing search, see if we should now allow it */
1482         if (lq_sta->stay_in_tbl) {
1483
1484                 /* Elapsed time using current modulation mode */
1485                 if (lq_sta->flush_timer)
1486                         flush_interval_passed =
1487                             time_after(jiffies,
1488                                        (unsigned long)(lq_sta->flush_timer +
1489                                         IWL_RATE_SCALE_FLUSH_INTVL));
1490
1491                 /* For now, disable the elapsed time criterion */
1492                 flush_interval_passed = 0;
1493
1494                 /*
1495                  * Check if we should allow search for new modulation mode.
1496                  * If many frames have failed or succeeded, or we've used
1497                  * this same modulation for a long time, allow search, and
1498                  * reset history stats that keep track of whether we should
1499                  * allow a new search.  Also (below) reset all bitmaps and
1500                  * stats in active history.
1501                  */
1502                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1503                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1504                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1505                      && (flush_interval_passed))) {
1506                         IWL_DEBUG_HT("LQ: stay is expired %d %d %d\n:",
1507                                      lq_sta->total_failed,
1508                                      lq_sta->total_success,
1509                                      flush_interval_passed);
1510
1511                         /* Allow search for new mode */
1512                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1513                         lq_sta->total_failed = 0;
1514                         lq_sta->total_success = 0;
1515                         lq_sta->flush_timer = 0;
1516
1517                 /*
1518                  * Else if we've used this modulation mode enough repetitions
1519                  * (regardless of elapsed time or success/failure), reset
1520                  * history bitmaps and rate-specific stats for all rates in
1521                  * active table.
1522                  */
1523                 } else {
1524                         lq_sta->table_count++;
1525                         if (lq_sta->table_count >=
1526                             lq_sta->table_count_limit) {
1527                                 lq_sta->table_count = 0;
1528
1529                                 IWL_DEBUG_HT("LQ: stay in table clear win\n");
1530                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1531                                         rs_rate_scale_clear_window(
1532                                                 &(tbl->win[i]));
1533                         }
1534                 }
1535
1536                 /* If transitioning to allow "search", reset all history
1537                  * bitmaps and stats in active table (this will become the new
1538                  * "search" table). */
1539                 if (!lq_sta->stay_in_tbl) {
1540                         for (i = 0; i < IWL_RATE_COUNT; i++)
1541                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1542                 }
1543         }
1544 }
1545
1546 /*
1547  * Do rate scaling and search for new modulation mode.
1548  */
1549 static void rs_rate_scale_perform(struct iwl4965_priv *priv,
1550                                   struct net_device *dev,
1551                                   struct ieee80211_hdr *hdr,
1552                                   struct sta_info *sta)
1553 {
1554         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1555         struct ieee80211_hw *hw = local_to_hw(local);
1556         struct ieee80211_conf *conf = &hw->conf;
1557         int low = IWL_RATE_INVALID;
1558         int high = IWL_RATE_INVALID;
1559         int index;
1560         int i;
1561         struct iwl4965_rate_scale_data *window = NULL;
1562         int current_tpt = IWL_INVALID_VALUE;
1563         int low_tpt = IWL_INVALID_VALUE;
1564         int high_tpt = IWL_INVALID_VALUE;
1565         u32 fail_count;
1566         s8 scale_action = 0;
1567         u16 fc, rate_mask;
1568         u8 update_lq = 0;
1569         struct iwl4965_lq_sta *lq_sta;
1570         struct iwl4965_scale_tbl_info *tbl, *tbl1;
1571         u16 rate_scale_index_msk = 0;
1572         struct iwl4965_rate mcs_rate;
1573         u8 is_green = 0;
1574         u8 active_tbl = 0;
1575         u8 done_search = 0;
1576         u16 high_low;
1577
1578         IWL_DEBUG_RATE("rate scale calculate new rate for skb\n");
1579
1580         fc = le16_to_cpu(hdr->frame_control);
1581         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1)) {
1582                 /* Send management frames and broadcast/multicast data using
1583                  * lowest rate. */
1584                 /* TODO: this could probably be improved.. */
1585                 return;
1586         }
1587
1588         if (!sta || !sta->rate_ctrl_priv)
1589                 return;
1590
1591         if (!priv->lq_mngr.lq_ready) {
1592                 IWL_DEBUG_RATE("still rate scaling not ready\n");
1593                 return;
1594         }
1595         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
1596
1597         /*
1598          * Select rate-scale / modulation-mode table to work with in
1599          * the rest of this function:  "search" if searching for better
1600          * modulation mode, or "active" if doing rate scaling within a mode.
1601          */
1602         if (!lq_sta->search_better_tbl)
1603                 active_tbl = lq_sta->active_tbl;
1604         else
1605                 active_tbl = 1 - lq_sta->active_tbl;
1606
1607         tbl = &(lq_sta->lq_info[active_tbl]);
1608         is_green = lq_sta->is_green;
1609
1610         /* current tx rate */
1611         index = sta->last_txrate;
1612
1613         IWL_DEBUG_RATE("Rate scale index %d for type %d\n", index,
1614                        tbl->lq_type);
1615
1616         /* rates available for this association, and for modulation mode */
1617         rs_get_supported_rates(lq_sta, hdr, tbl->lq_type,
1618                                 &rate_mask);
1619
1620         IWL_DEBUG_RATE("mask 0x%04X \n", rate_mask);
1621
1622         /* mask with station rate restriction */
1623         if (is_legacy(tbl->lq_type)) {
1624                 if (lq_sta->phymode == (u8) MODE_IEEE80211A)
1625                         /* supp_rates has no CCK bits in A mode */
1626                         rate_scale_index_msk = (u16) (rate_mask &
1627                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1628                 else
1629                         rate_scale_index_msk = (u16) (rate_mask &
1630                                                       lq_sta->supp_rates);
1631
1632         } else
1633                 rate_scale_index_msk = rate_mask;
1634
1635         if (!rate_scale_index_msk)
1636                 rate_scale_index_msk = rate_mask;
1637
1638         /* If current rate is no longer supported on current association,
1639          * or user changed preferences for rates, find a new supported rate. */
1640         if (index < 0 || !((1 << index) & rate_scale_index_msk)) {
1641                 index = IWL_INVALID_VALUE;
1642                 update_lq = 1;
1643
1644                 /* get the highest available rate */
1645                 for (i = 0; i <= IWL_RATE_COUNT; i++) {
1646                         if ((1 << i) & rate_scale_index_msk)
1647                                 index = i;
1648                 }
1649
1650                 if (index == IWL_INVALID_VALUE) {
1651                         IWL_WARNING("Can not find a suitable rate\n");
1652                         return;
1653                 }
1654         }
1655
1656         /* Get expected throughput table and history window for current rate */
1657         if (!tbl->expected_tpt)
1658                 rs_get_expected_tpt_table(lq_sta, tbl);
1659
1660         window = &(tbl->win[index]);
1661
1662         /*
1663          * If there is not enough history to calculate actual average
1664          * throughput, keep analyzing results of more tx frames, without
1665          * changing rate or mode (bypass most of the rest of this function).
1666          * Set up new rate table in uCode only if old rate is not supported
1667          * in current association (use new rate found above).
1668          */
1669         fail_count = window->counter - window->success_counter;
1670         if (((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1671              (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))
1672             || (tbl->expected_tpt == NULL)) {
1673                 IWL_DEBUG_RATE("LQ: still below TH succ %d total %d "
1674                                "for index %d\n",
1675                                window->success_counter, window->counter, index);
1676
1677                 /* Can't calculate this yet; not enough history */
1678                 window->average_tpt = IWL_INVALID_VALUE;
1679
1680                 /* Should we stay with this modulation mode,
1681                  * or search for a new one? */
1682                 rs_stay_in_table(lq_sta);
1683
1684                 /* Set up new rate table in uCode, if needed */
1685                 if (update_lq) {
1686                         rs_mcs_from_tbl(&mcs_rate, tbl, index, is_green);
1687                         rs_fill_link_cmd(lq_sta, &mcs_rate, &lq_sta->lq);
1688                         rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1689                 }
1690                 goto out;
1691
1692         /* Else we have enough samples; calculate estimate of
1693          * actual average throughput */
1694         } else
1695                 window->average_tpt = ((window->success_ratio *
1696                                         tbl->expected_tpt[index] + 64) / 128);
1697
1698         /* If we are searching for better modulation mode, check success. */
1699         if (lq_sta->search_better_tbl) {
1700                 int success_limit = IWL_RATE_SCALE_SWITCH;
1701
1702                 /* If good success, continue using the "search" mode;
1703                  * no need to send new link quality command, since we're
1704                  * continuing to use the setup that we've been trying. */
1705                 if ((window->success_ratio > success_limit) ||
1706                     (window->average_tpt > lq_sta->last_tpt)) {
1707                         if (!is_legacy(tbl->lq_type)) {
1708                                 IWL_DEBUG_HT("LQ: we are switching to HT"
1709                                              " rate suc %d current tpt %d"
1710                                              " old tpt %d\n",
1711                                              window->success_ratio,
1712                                              window->average_tpt,
1713                                              lq_sta->last_tpt);
1714                                 lq_sta->enable_counter = 1;
1715                         }
1716                         /* Swap tables; "search" becomes "active" */
1717                         lq_sta->active_tbl = active_tbl;
1718                         current_tpt = window->average_tpt;
1719
1720                 /* Else poor success; go back to mode in "active" table */
1721                 } else {
1722                         /* Nullify "search" table */
1723                         tbl->lq_type = LQ_NONE;
1724
1725                         /* Revert to "active" table */
1726                         active_tbl = lq_sta->active_tbl;
1727                         tbl = &(lq_sta->lq_info[active_tbl]);
1728
1729                         /* Revert to "active" rate and throughput info */
1730                         index = iwl4965_rate_index_from_plcp(
1731                                 tbl->current_rate.rate_n_flags);
1732                         current_tpt = lq_sta->last_tpt;
1733
1734                         /* Need to set up a new rate table in uCode */
1735                         update_lq = 1;
1736                         IWL_DEBUG_HT("XXY GO BACK TO OLD TABLE\n");
1737                 }
1738
1739                 /* Either way, we've made a decision; modulation mode
1740                  * search is done, allow rate adjustment next time. */
1741                 lq_sta->search_better_tbl = 0;
1742                 done_search = 1;        /* Don't switch modes below! */
1743                 goto lq_update;
1744         }
1745
1746         /* (Else) not in search of better modulation mode, try for better
1747          * starting rate, while staying in this mode. */
1748         high_low = rs_get_adjacent_rate(index, rate_scale_index_msk,
1749                                         tbl->lq_type);
1750         low = high_low & 0xff;
1751         high = (high_low >> 8) & 0xff;
1752
1753         /* Collect measured throughputs for current and adjacent rates */
1754         current_tpt = window->average_tpt;
1755         if (low != IWL_RATE_INVALID)
1756                 low_tpt = tbl->win[low].average_tpt;
1757         if (high != IWL_RATE_INVALID)
1758                 high_tpt = tbl->win[high].average_tpt;
1759
1760         /* Assume rate increase */
1761         scale_action = 1;
1762
1763         /* Too many failures, decrease rate */
1764         if ((window->success_ratio <= IWL_RATE_DECREASE_TH) ||
1765             (current_tpt == 0)) {
1766                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
1767                 scale_action = -1;
1768
1769         /* No throughput measured yet for adjacent rates; try increase. */
1770         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1771                    (high_tpt == IWL_INVALID_VALUE))
1772                 scale_action = 1;
1773
1774         /* Both adjacent throughputs are measured, but neither one has better
1775          * throughput; we're using the best rate, don't change it! */
1776         else if ((low_tpt != IWL_INVALID_VALUE) &&
1777                  (high_tpt != IWL_INVALID_VALUE) &&
1778                  (low_tpt < current_tpt) &&
1779                  (high_tpt < current_tpt))
1780                 scale_action = 0;
1781
1782         /* At least one adjacent rate's throughput is measured,
1783          * and may have better performance. */
1784         else {
1785                 /* Higher adjacent rate's throughput is measured */
1786                 if (high_tpt != IWL_INVALID_VALUE) {
1787                         /* Higher rate has better throughput */
1788                         if (high_tpt > current_tpt)
1789                                 scale_action = 1;
1790                         else {
1791                                 IWL_DEBUG_RATE
1792                                     ("decrease rate because of high tpt\n");
1793                                 scale_action = -1;
1794                         }
1795
1796                 /* Lower adjacent rate's throughput is measured */
1797                 } else if (low_tpt != IWL_INVALID_VALUE) {
1798                         /* Lower rate has better throughput */
1799                         if (low_tpt > current_tpt) {
1800                                 IWL_DEBUG_RATE
1801                                     ("decrease rate because of low tpt\n");
1802                                 scale_action = -1;
1803                         } else
1804                                 scale_action = 1;
1805                 }
1806         }
1807
1808         /* Sanity check; asked for decrease, but success rate or throughput
1809          * has been good at old rate.  Don't change it. */
1810         if (scale_action == -1) {
1811                 if ((low != IWL_RATE_INVALID) &&
1812                     ((window->success_ratio > IWL_RATE_HIGH_TH) ||
1813                      (current_tpt > (100 * tbl->expected_tpt[low]))))
1814                         scale_action = 0;
1815
1816         /* Sanity check; asked for increase, but success rate has not been great
1817          * even at old rate, higher rate will be worse.  Don't change it. */
1818         } else if ((scale_action == 1) &&
1819                    (window->success_ratio < IWL_RATE_INCREASE_TH))
1820                 scale_action = 0;
1821
1822         switch (scale_action) {
1823         case -1:
1824                 /* Decrease starting rate, update uCode's rate table */
1825                 if (low != IWL_RATE_INVALID) {
1826                         update_lq = 1;
1827                         index = low;
1828                 }
1829                 break;
1830         case 1:
1831                 /* Increase starting rate, update uCode's rate table */
1832                 if (high != IWL_RATE_INVALID) {
1833                         update_lq = 1;
1834                         index = high;
1835                 }
1836
1837                 break;
1838         case 0:
1839                 /* No change */
1840         default:
1841                 break;
1842         }
1843
1844         IWL_DEBUG_HT("choose rate scale index %d action %d low %d "
1845                     "high %d type %d\n",
1846                      index, scale_action, low, high, tbl->lq_type);
1847
1848  lq_update:
1849         /* Replace uCode's rate table for the destination station. */
1850         if (update_lq) {
1851                 rs_mcs_from_tbl(&mcs_rate, tbl, index, is_green);
1852                 rs_fill_link_cmd(lq_sta, &mcs_rate, &lq_sta->lq);
1853                 rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1854         }
1855
1856         /* Should we stay with this modulation mode, or search for a new one? */
1857         rs_stay_in_table(lq_sta);
1858
1859         /*
1860          * Search for new modulation mode if we're:
1861          * 1)  Not changing rates right now
1862          * 2)  Not just finishing up a search
1863          * 3)  Allowing a new search
1864          */
1865         if (!update_lq && !done_search && !lq_sta->stay_in_tbl) {
1866                 /* Save current throughput to compare with "search" throughput*/
1867                 lq_sta->last_tpt = current_tpt;
1868
1869                 /* Select a new "search" modulation mode to try.
1870                  * If one is found, set up the new "search" table. */
1871                 if (is_legacy(tbl->lq_type))
1872                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
1873                 else if (is_siso(tbl->lq_type))
1874                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
1875                 else
1876                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
1877
1878                 /* If new "search" mode was selected, set up in uCode table */
1879                 if (lq_sta->search_better_tbl) {
1880                         /* Access the "search" table, clear its history. */
1881                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1882                         for (i = 0; i < IWL_RATE_COUNT; i++)
1883                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1884
1885                         /* Use new "search" start rate */
1886                         index = iwl4965_rate_index_from_plcp(
1887                                         tbl->current_rate.rate_n_flags);
1888
1889                         IWL_DEBUG_HT("Switch current  mcs: %X index: %d\n",
1890                                      tbl->current_rate.rate_n_flags, index);
1891                         rs_fill_link_cmd(lq_sta, &tbl->current_rate,
1892                                          &lq_sta->lq);
1893                         rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1894                 }
1895
1896                 /* If the "active" (non-search) mode was legacy,
1897                  * and we've tried switching antennas,
1898                  * but we haven't been able to try HT modes (not available),
1899                  * stay with best antenna legacy modulation for a while
1900                  * before next round of mode comparisons. */
1901                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
1902                 if (is_legacy(tbl1->lq_type) &&
1903 #ifdef CONFIG_IWL4965_HT
1904                    (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE)) &&
1905 #endif
1906                     (lq_sta->action_counter >= 1)) {
1907                         lq_sta->action_counter = 0;
1908                         IWL_DEBUG_HT("LQ: STAY in legacy table\n");
1909                         rs_set_stay_in_table(1, lq_sta);
1910                 }
1911
1912                 /* If we're in an HT mode, and all 3 mode switch actions
1913                  * have been tried and compared, stay in this best modulation
1914                  * mode for a while before next round of mode comparisons. */
1915                 if (lq_sta->enable_counter &&
1916                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
1917 #ifdef CONFIG_IWL4965_HT_AGG
1918                         /* If appropriate, set up aggregation! */
1919                         if ((lq_sta->last_tpt > TID_AGG_TPT_THREHOLD) &&
1920                             (priv->lq_mngr.agg_ctrl.auto_agg)) {
1921                                 priv->lq_mngr.agg_ctrl.tid_retry =
1922                                     TID_ALL_SPECIFIED;
1923                                 schedule_work(&priv->agg_work);
1924                         }
1925 #endif /*CONFIG_IWL4965_HT_AGG */
1926                         lq_sta->action_counter = 0;
1927                         rs_set_stay_in_table(0, lq_sta);
1928                 }
1929
1930         /*
1931          * Else, don't search for a new modulation mode.
1932          * Put new timestamp in stay-in-modulation-mode flush timer if:
1933          * 1)  Not changing rates right now
1934          * 2)  Not just finishing up a search
1935          * 3)  flush timer is empty
1936          */
1937         } else {
1938                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
1939                         lq_sta->flush_timer = jiffies;
1940         }
1941
1942 out:
1943         rs_mcs_from_tbl(&tbl->current_rate, tbl, index, is_green);
1944         i = index;
1945         sta->last_txrate = i;
1946
1947         /* sta->txrate is an index to A mode rates which start
1948          * at IWL_FIRST_OFDM_RATE
1949          */
1950         if (lq_sta->phymode == (u8) MODE_IEEE80211A)
1951                 sta->txrate = i - IWL_FIRST_OFDM_RATE;
1952         else
1953                 sta->txrate = i;
1954
1955         return;
1956 }
1957
1958
1959 static void rs_initialize_lq(struct iwl4965_priv *priv,
1960                              struct ieee80211_conf *conf,
1961                              struct sta_info *sta)
1962 {
1963         int i;
1964         struct iwl4965_lq_sta *lq_sta;
1965         struct iwl4965_scale_tbl_info *tbl;
1966         u8 active_tbl = 0;
1967         int rate_idx;
1968         u8 use_green = rs_use_green(priv, conf);
1969         struct iwl4965_rate mcs_rate;
1970
1971         if (!sta || !sta->rate_ctrl_priv)
1972                 goto out;
1973
1974         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
1975         i = sta->last_txrate;
1976
1977         if ((lq_sta->lq.sta_id == 0xff) &&
1978             (priv->iw_mode == IEEE80211_IF_TYPE_IBSS))
1979                 goto out;
1980
1981         if (!lq_sta->search_better_tbl)
1982                 active_tbl = lq_sta->active_tbl;
1983         else
1984                 active_tbl = 1 - lq_sta->active_tbl;
1985
1986         tbl = &(lq_sta->lq_info[active_tbl]);
1987
1988         if ((i < 0) || (i >= IWL_RATE_COUNT))
1989                 i = 0;
1990
1991         mcs_rate.rate_n_flags = iwl4965_rates[i].plcp ;
1992         mcs_rate.rate_n_flags |= RATE_MCS_ANT_B_MSK;
1993         mcs_rate.rate_n_flags &= ~RATE_MCS_ANT_A_MSK;
1994
1995         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
1996                 mcs_rate.rate_n_flags |= RATE_MCS_CCK_MSK;
1997
1998         tbl->antenna_type = ANT_AUX;
1999         rs_get_tbl_info_from_mcs(&mcs_rate, priv->phymode, tbl, &rate_idx);
2000         if (!rs_is_ant_connected(priv->valid_antenna, tbl->antenna_type))
2001             rs_toggle_antenna(&mcs_rate, tbl);
2002
2003         rs_mcs_from_tbl(&mcs_rate, tbl, rate_idx, use_green);
2004         tbl->current_rate.rate_n_flags = mcs_rate.rate_n_flags;
2005         rs_get_expected_tpt_table(lq_sta, tbl);
2006         rs_fill_link_cmd(lq_sta, &mcs_rate, &lq_sta->lq);
2007         rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2008  out:
2009         return;
2010 }
2011
2012 static void rs_get_rate(void *priv_rate, struct net_device *dev,
2013                         struct ieee80211_hw_mode *mode, struct sk_buff *skb,
2014                         struct rate_selection *sel)
2015 {
2016
2017         int i;
2018         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
2019         struct ieee80211_conf *conf = &local->hw.conf;
2020         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2021         struct sta_info *sta;
2022         u16 fc;
2023         struct iwl4965_priv *priv = (struct iwl4965_priv *)priv_rate;
2024         struct iwl4965_lq_sta *lq_sta;
2025
2026         IWL_DEBUG_RATE_LIMIT("rate scale calculate new rate for skb\n");
2027
2028         sta = sta_info_get(local, hdr->addr1);
2029
2030         /* Send management frames and broadcast/multicast data using lowest
2031          * rate. */
2032         fc = le16_to_cpu(hdr->frame_control);
2033         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1) ||
2034             !sta || !sta->rate_ctrl_priv) {
2035                 sel->rate = rate_lowest(local, local->oper_hw_mode, sta);
2036                 if (sta)
2037                         sta_info_put(sta);
2038                 return;
2039         }
2040
2041         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
2042         i = sta->last_txrate;
2043
2044         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
2045             !lq_sta->ibss_sta_added) {
2046                 u8 sta_id = iwl4965_hw_find_station(priv, hdr->addr1);
2047                 DECLARE_MAC_BUF(mac);
2048
2049                 if (sta_id == IWL_INVALID_STATION) {
2050                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
2051                                        print_mac(mac, hdr->addr1));
2052                         sta_id = iwl4965_add_station_flags(priv, hdr->addr1,
2053                                                         0, CMD_ASYNC, NULL);
2054                 }
2055                 if ((sta_id != IWL_INVALID_STATION)) {
2056                         lq_sta->lq.sta_id = sta_id;
2057                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2058                         lq_sta->ibss_sta_added = 1;
2059                         rs_initialize_lq(priv, conf, sta);
2060                 }
2061                 if (!lq_sta->ibss_sta_added)
2062                         goto done;
2063         }
2064
2065  done:
2066         if ((i < 0) || (i > IWL_RATE_COUNT)) {
2067                 sel->rate = rate_lowest(local, local->oper_hw_mode, sta);
2068                 return;
2069         }
2070         sta_info_put(sta);
2071
2072         sel->rate = &priv->ieee_rates[i];
2073 }
2074
2075 static void *rs_alloc_sta(void *priv, gfp_t gfp)
2076 {
2077         struct iwl4965_lq_sta *lq_sta;
2078         int i, j;
2079
2080         IWL_DEBUG_RATE("create station rate scale window\n");
2081
2082         lq_sta = kzalloc(sizeof(struct iwl4965_lq_sta), gfp);
2083
2084         if (lq_sta == NULL)
2085                 return NULL;
2086         lq_sta->lq.sta_id = 0xff;
2087
2088
2089         for (j = 0; j < LQ_SIZE; j++)
2090                 for (i = 0; i < IWL_RATE_COUNT; i++)
2091                         rs_rate_scale_clear_window(&(lq_sta->lq_info[j].win[i]));
2092
2093         return lq_sta;
2094 }
2095
2096 static void rs_rate_init(void *priv_rate, void *priv_sta,
2097                          struct ieee80211_local *local,
2098                          struct sta_info *sta)
2099 {
2100         int i, j;
2101         struct ieee80211_conf *conf = &local->hw.conf;
2102         struct ieee80211_hw_mode *mode = local->oper_hw_mode;
2103         struct iwl4965_priv *priv = (struct iwl4965_priv *)priv_rate;
2104         struct iwl4965_lq_sta *lq_sta = priv_sta;
2105
2106         lq_sta->flush_timer = 0;
2107         lq_sta->supp_rates = sta->supp_rates;
2108         sta->txrate = 3;
2109         for (j = 0; j < LQ_SIZE; j++)
2110                 for (i = 0; i < IWL_RATE_COUNT; i++)
2111                         rs_rate_scale_clear_window(&(lq_sta->lq_info[j].win[i]));
2112
2113         IWL_DEBUG_RATE("rate scale global init\n");
2114         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2115          * the lowest or the highest rate.. Could consider using RSSI from
2116          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2117          * after assoc.. */
2118
2119         lq_sta->ibss_sta_added = 0;
2120         if (priv->iw_mode == IEEE80211_IF_TYPE_AP) {
2121                 u8 sta_id = iwl4965_hw_find_station(priv, sta->addr);
2122                 DECLARE_MAC_BUF(mac);
2123
2124                 /* for IBSS the call are from tasklet */
2125                 IWL_DEBUG_HT("LQ: ADD station %s\n",
2126                              print_mac(mac, sta->addr));
2127
2128                 if (sta_id == IWL_INVALID_STATION) {
2129                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
2130                                        print_mac(mac, sta->addr));
2131                         sta_id = iwl4965_add_station_flags(priv, sta->addr,
2132                                                         0, CMD_ASYNC, NULL);
2133                 }
2134                 if ((sta_id != IWL_INVALID_STATION)) {
2135                         lq_sta->lq.sta_id = sta_id;
2136                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2137                 }
2138                 /* FIXME: this is w/a remove it later */
2139                 priv->assoc_station_added = 1;
2140         }
2141
2142         /* Find highest tx rate supported by hardware and destination station */
2143         for (i = 0; i < mode->num_rates; i++) {
2144                 if ((sta->supp_rates & BIT(i)) &&
2145                     (mode->rates[i].flags & IEEE80211_RATE_SUPPORTED))
2146                         sta->txrate = i;
2147         }
2148         sta->last_txrate = sta->txrate;
2149         /* For MODE_IEEE80211A, cck rates are at end of rate table */
2150         if (local->hw.conf.phymode == MODE_IEEE80211A)
2151                 sta->last_txrate += IWL_FIRST_OFDM_RATE;
2152
2153         lq_sta->is_dup = 0;
2154         lq_sta->valid_antenna = priv->valid_antenna;
2155         lq_sta->antenna = priv->antenna;
2156         lq_sta->is_green = rs_use_green(priv, conf);
2157         lq_sta->active_rate = priv->active_rate;
2158         lq_sta->active_rate &= ~(0x1000);
2159         lq_sta->active_rate_basic = priv->active_rate_basic;
2160         lq_sta->phymode = priv->phymode;
2161 #ifdef CONFIG_IWL4965_HT
2162         /*
2163          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2164          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2165          */
2166         lq_sta->active_siso_rate = (priv->current_ht_config.supp_mcs_set[0] << 1);
2167         lq_sta->active_siso_rate |=
2168                         (priv->current_ht_config.supp_mcs_set[0] & 0x1);
2169         lq_sta->active_siso_rate &= ~((u16)0x2);
2170         lq_sta->active_siso_rate =
2171                         lq_sta->active_siso_rate << IWL_FIRST_OFDM_RATE;
2172
2173         /* Same here */
2174         lq_sta->active_mimo_rate = (priv->current_ht_config.supp_mcs_set[1] << 1);
2175         lq_sta->active_mimo_rate |=
2176                         (priv->current_ht_config.supp_mcs_set[1] & 0x1);
2177         lq_sta->active_mimo_rate &= ~((u16)0x2);
2178         lq_sta->active_mimo_rate =
2179                         lq_sta->active_mimo_rate << IWL_FIRST_OFDM_RATE;
2180         IWL_DEBUG_HT("SISO RATE 0x%X MIMO RATE 0x%X\n",
2181                      lq_sta->active_siso_rate,
2182                      lq_sta->active_mimo_rate);
2183 #endif /*CONFIG_IWL4965_HT*/
2184 #ifdef CONFIG_MAC80211_DEBUGFS
2185         lq_sta->drv = priv;
2186 #endif
2187
2188         if (priv->assoc_station_added)
2189                 priv->lq_mngr.lq_ready = 1;
2190
2191         rs_initialize_lq(priv, conf, sta);
2192 }
2193
2194 static void rs_fill_link_cmd(struct iwl4965_lq_sta *lq_sta,
2195                             struct iwl4965_rate *tx_mcs,
2196                             struct iwl4965_link_quality_cmd *lq_cmd)
2197 {
2198         int index = 0;
2199         int rate_idx;
2200         int repeat_rate = 0;
2201         u8 ant_toggle_count = 0;
2202         u8 use_ht_possible = 1;
2203         struct iwl4965_rate new_rate;
2204         struct iwl4965_scale_tbl_info tbl_type = { 0 };
2205
2206         /* Override starting rate (index 0) if needed for debug purposes */
2207         rs_dbgfs_set_mcs(lq_sta, tx_mcs, index);
2208
2209         /* Interpret rate_n_flags */
2210         rs_get_tbl_info_from_mcs(tx_mcs, lq_sta->phymode,
2211                                   &tbl_type, &rate_idx);
2212
2213         /* How many times should we repeat the initial rate? */
2214         if (is_legacy(tbl_type.lq_type)) {
2215                 ant_toggle_count = 1;
2216                 repeat_rate = IWL_NUMBER_TRY;
2217         } else
2218                 repeat_rate = IWL_HT_NUMBER_TRY;
2219
2220         lq_cmd->general_params.mimo_delimiter =
2221                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2222
2223         /* Fill 1st table entry (index 0) */
2224         lq_cmd->rs_table[index].rate_n_flags =
2225                         cpu_to_le32(tx_mcs->rate_n_flags);
2226         new_rate.rate_n_flags = tx_mcs->rate_n_flags;
2227
2228         if (is_mimo(tbl_type.lq_type) || (tbl_type.antenna_type == ANT_MAIN))
2229                 lq_cmd->general_params.single_stream_ant_msk
2230                         = LINK_QUAL_ANT_A_MSK;
2231         else
2232                 lq_cmd->general_params.single_stream_ant_msk
2233                         = LINK_QUAL_ANT_B_MSK;
2234
2235         index++;
2236         repeat_rate--;
2237
2238         /* Fill rest of rate table */
2239         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2240                 /* Repeat initial/next rate.
2241                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2242                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2243                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2244                         if (is_legacy(tbl_type.lq_type)) {
2245                                 if (ant_toggle_count <
2246                                     NUM_TRY_BEFORE_ANTENNA_TOGGLE)
2247                                         ant_toggle_count++;
2248                                 else {
2249                                         rs_toggle_antenna(&new_rate, &tbl_type);
2250                                         ant_toggle_count = 1;
2251                                 }
2252                         }
2253
2254                         /* Override next rate if needed for debug purposes */
2255                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2256
2257                         /* Fill next table entry */
2258                         lq_cmd->rs_table[index].rate_n_flags =
2259                                         cpu_to_le32(new_rate.rate_n_flags);
2260                         repeat_rate--;
2261                         index++;
2262                 }
2263
2264                 rs_get_tbl_info_from_mcs(&new_rate, lq_sta->phymode, &tbl_type,
2265                                                 &rate_idx);
2266
2267                 /* Indicate to uCode which entries might be MIMO.
2268                  * If initial rate was MIMO, this will finally end up
2269                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2270                 if (is_mimo(tbl_type.lq_type))
2271                         lq_cmd->general_params.mimo_delimiter = index;
2272
2273                 /* Get next rate */
2274                 rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2275                                   use_ht_possible, &new_rate);
2276
2277                 /* How many times should we repeat the next rate? */
2278                 if (is_legacy(tbl_type.lq_type)) {
2279                         if (ant_toggle_count < NUM_TRY_BEFORE_ANTENNA_TOGGLE)
2280                                 ant_toggle_count++;
2281                         else {
2282                                 rs_toggle_antenna(&new_rate, &tbl_type);
2283                                 ant_toggle_count = 1;
2284                         }
2285                         repeat_rate = IWL_NUMBER_TRY;
2286                 } else
2287                         repeat_rate = IWL_HT_NUMBER_TRY;
2288
2289                 /* Don't allow HT rates after next pass.
2290                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2291                 use_ht_possible = 0;
2292
2293                 /* Override next rate if needed for debug purposes */
2294                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2295
2296                 /* Fill next table entry */
2297                 lq_cmd->rs_table[index].rate_n_flags =
2298                                 cpu_to_le32(new_rate.rate_n_flags);
2299
2300                 index++;
2301                 repeat_rate--;
2302         }
2303
2304         lq_cmd->general_params.dual_stream_ant_msk = 3;
2305         lq_cmd->agg_params.agg_dis_start_th = 3;
2306         lq_cmd->agg_params.agg_time_limit = cpu_to_le16(4000);
2307 }
2308
2309 static void *rs_alloc(struct ieee80211_local *local)
2310 {
2311         return local->hw.priv;
2312 }
2313 /* rate scale requires free function to be implemented */
2314 static void rs_free(void *priv_rate)
2315 {
2316         return;
2317 }
2318
2319 static void rs_clear(void *priv_rate)
2320 {
2321         struct iwl4965_priv *priv = (struct iwl4965_priv *) priv_rate;
2322
2323         IWL_DEBUG_RATE("enter\n");
2324
2325         priv->lq_mngr.lq_ready = 0;
2326 #ifdef CONFIG_IWL4965_HT
2327 #ifdef CONFIG_IWL4965_HT_AGG
2328         if (priv->lq_mngr.agg_ctrl.granted_ba)
2329                 iwl4965_turn_off_agg(priv, TID_ALL_SPECIFIED);
2330 #endif /*CONFIG_IWL4965_HT_AGG */
2331 #endif /* CONFIG_IWL4965_HT */
2332
2333         IWL_DEBUG_RATE("leave\n");
2334 }
2335
2336 static void rs_free_sta(void *priv, void *priv_sta)
2337 {
2338         struct iwl4965_lq_sta *lq_sta = priv_sta;
2339
2340         IWL_DEBUG_RATE("enter\n");
2341         kfree(lq_sta);
2342         IWL_DEBUG_RATE("leave\n");
2343 }
2344
2345
2346 #ifdef CONFIG_MAC80211_DEBUGFS
2347 static int open_file_generic(struct inode *inode, struct file *file)
2348 {
2349         file->private_data = inode->i_private;
2350         return 0;
2351 }
2352 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
2353                                 struct iwl4965_rate *mcs, int index)
2354 {
2355         u32 base_rate;
2356
2357         if (lq_sta->phymode == (u8) MODE_IEEE80211A)
2358                 base_rate = 0x800D;
2359         else
2360                 base_rate = 0x820A;
2361
2362         if (lq_sta->dbg_fixed.rate_n_flags) {
2363                 if (index < 12)
2364                         mcs->rate_n_flags = lq_sta->dbg_fixed.rate_n_flags;
2365                 else
2366                         mcs->rate_n_flags = base_rate;
2367                 IWL_DEBUG_RATE("Fixed rate ON\n");
2368                 return;
2369         }
2370
2371         IWL_DEBUG_RATE("Fixed rate OFF\n");
2372 }
2373
2374 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2375                         const char __user *user_buf, size_t count, loff_t *ppos)
2376 {
2377         struct iwl4965_lq_sta *lq_sta = file->private_data;
2378         char buf[64];
2379         int buf_size;
2380         u32 parsed_rate;
2381
2382         memset(buf, 0, sizeof(buf));
2383         buf_size = min(count, sizeof(buf) -  1);
2384         if (copy_from_user(buf, user_buf, buf_size))
2385                 return -EFAULT;
2386
2387         if (sscanf(buf, "%x", &parsed_rate) == 1)
2388                 lq_sta->dbg_fixed.rate_n_flags = parsed_rate;
2389         else
2390                 lq_sta->dbg_fixed.rate_n_flags = 0;
2391
2392         lq_sta->active_rate = 0x0FFF;   /* 1 - 54 MBits, includes CCK */
2393         lq_sta->active_siso_rate = 0x1FD0;      /* 6 - 60 MBits, no 9, no CCK */
2394         lq_sta->active_mimo_rate = 0x1FD0;      /* 6 - 60 MBits, no 9, no CCK */
2395
2396         IWL_DEBUG_RATE("sta_id %d rate 0x%X\n",
2397                 lq_sta->lq.sta_id, lq_sta->dbg_fixed.rate_n_flags);
2398
2399         if (lq_sta->dbg_fixed.rate_n_flags) {
2400                 rs_fill_link_cmd(lq_sta, &lq_sta->dbg_fixed, &lq_sta->lq);
2401                 rs_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2402         }
2403
2404         return count;
2405 }
2406
2407 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2408                         char __user *user_buf, size_t count, loff_t *ppos)
2409 {
2410         char buff[1024];
2411         int desc = 0;
2412         int i = 0;
2413
2414         struct iwl4965_lq_sta *lq_sta = file->private_data;
2415
2416         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2417         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2418                         lq_sta->total_failed, lq_sta->total_success,
2419                         lq_sta->active_rate);
2420         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2421                         lq_sta->dbg_fixed.rate_n_flags);
2422         desc += sprintf(buff+desc, "general:"
2423                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2424                 lq_sta->lq.general_params.flags,
2425                 lq_sta->lq.general_params.mimo_delimiter,
2426                 lq_sta->lq.general_params.single_stream_ant_msk,
2427                 lq_sta->lq.general_params.dual_stream_ant_msk);
2428
2429         desc += sprintf(buff+desc, "agg:"
2430                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2431                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2432                         lq_sta->lq.agg_params.agg_dis_start_th,
2433                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2434
2435         desc += sprintf(buff+desc,
2436                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2437                         lq_sta->lq.general_params.start_rate_index[0],
2438                         lq_sta->lq.general_params.start_rate_index[1],
2439                         lq_sta->lq.general_params.start_rate_index[2],
2440                         lq_sta->lq.general_params.start_rate_index[3]);
2441
2442
2443         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2444                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2445                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2446
2447         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2448 }
2449
2450 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2451         .write = rs_sta_dbgfs_scale_table_write,
2452         .read = rs_sta_dbgfs_scale_table_read,
2453         .open = open_file_generic,
2454 };
2455 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2456                         char __user *user_buf, size_t count, loff_t *ppos)
2457 {
2458         char buff[1024];
2459         int desc = 0;
2460         int i, j;
2461
2462         struct iwl4965_lq_sta *lq_sta = file->private_data;
2463         for (i = 0; i < LQ_SIZE; i++) {
2464                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2465                                 "rate=0x%X\n",
2466                                 lq_sta->active_tbl == i?"*":"x",
2467                                 lq_sta->lq_info[i].lq_type,
2468                                 lq_sta->lq_info[i].is_SGI,
2469                                 lq_sta->lq_info[i].is_fat,
2470                                 lq_sta->lq_info[i].is_dup,
2471                                 lq_sta->lq_info[i].current_rate.rate_n_flags);
2472                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2473                         desc += sprintf(buff+desc,
2474                                 "counter=%d success=%d %%=%d\n",
2475                                 lq_sta->lq_info[i].win[j].counter,
2476                                 lq_sta->lq_info[i].win[j].success_counter,
2477                                 lq_sta->lq_info[i].win[j].success_ratio);
2478                 }
2479         }
2480         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2481 }
2482
2483 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2484         .read = rs_sta_dbgfs_stats_table_read,
2485         .open = open_file_generic,
2486 };
2487
2488 static void rs_add_debugfs(void *priv, void *priv_sta,
2489                                         struct dentry *dir)
2490 {
2491         struct iwl4965_lq_sta *lq_sta = priv_sta;
2492         lq_sta->rs_sta_dbgfs_scale_table_file =
2493                 debugfs_create_file("rate_scale_table", 0600, dir,
2494                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2495         lq_sta->rs_sta_dbgfs_stats_table_file =
2496                 debugfs_create_file("rate_stats_table", 0600, dir,
2497                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2498 }
2499
2500 static void rs_remove_debugfs(void *priv, void *priv_sta)
2501 {
2502         struct iwl4965_lq_sta *lq_sta = priv_sta;
2503         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2504         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2505 }
2506 #endif
2507
2508 static struct rate_control_ops rs_ops = {
2509         .module = NULL,
2510         .name = RS_NAME,
2511         .tx_status = rs_tx_status,
2512         .get_rate = rs_get_rate,
2513         .rate_init = rs_rate_init,
2514         .clear = rs_clear,
2515         .alloc = rs_alloc,
2516         .free = rs_free,
2517         .alloc_sta = rs_alloc_sta,
2518         .free_sta = rs_free_sta,
2519 #ifdef CONFIG_MAC80211_DEBUGFS
2520         .add_sta_debugfs = rs_add_debugfs,
2521         .remove_sta_debugfs = rs_remove_debugfs,
2522 #endif
2523 };
2524
2525 int iwl4965_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
2526 {
2527         struct ieee80211_local *local = hw_to_local(hw);
2528         struct iwl4965_priv *priv = hw->priv;
2529         struct iwl4965_lq_sta *lq_sta;
2530         struct sta_info *sta;
2531         int cnt = 0, i;
2532         u32 samples = 0, success = 0, good = 0;
2533         unsigned long now = jiffies;
2534         u32 max_time = 0;
2535         u8 lq_type, antenna;
2536
2537         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
2538         if (!sta || !sta->rate_ctrl_priv) {
2539                 if (sta) {
2540                         sta_info_put(sta);
2541                         IWL_DEBUG_RATE("leave - no private rate data!\n");
2542                 } else
2543                         IWL_DEBUG_RATE("leave - no station!\n");
2544                 return sprintf(buf, "station %d not found\n", sta_id);
2545         }
2546
2547         lq_sta = (void *)sta->rate_ctrl_priv;
2548
2549         lq_type = lq_sta->lq_info[lq_sta->active_tbl].lq_type;
2550         antenna = lq_sta->lq_info[lq_sta->active_tbl].antenna_type;
2551
2552         if (is_legacy(lq_type))
2553                 i = IWL_RATE_54M_INDEX;
2554         else
2555                 i = IWL_RATE_60M_INDEX;
2556         while (1) {
2557                 u64 mask;
2558                 int j;
2559                 int active = lq_sta->active_tbl;
2560
2561                 cnt +=
2562                     sprintf(&buf[cnt], " %2dMbs: ", iwl4965_rates[i].ieee / 2);
2563
2564                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
2565                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
2566                         buf[cnt++] =
2567                                 (lq_sta->lq_info[active].win[i].data & mask)
2568                                 ? '1' : '0';
2569
2570                 samples += lq_sta->lq_info[active].win[i].counter;
2571                 good += lq_sta->lq_info[active].win[i].success_counter;
2572                 success += lq_sta->lq_info[active].win[i].success_counter *
2573                            iwl4965_rates[i].ieee;
2574
2575                 if (lq_sta->lq_info[active].win[i].stamp) {
2576                         int delta =
2577                                    jiffies_to_msecs(now -
2578                                    lq_sta->lq_info[active].win[i].stamp);
2579
2580                         if (delta > max_time)
2581                                 max_time = delta;
2582
2583                         cnt += sprintf(&buf[cnt], "%5dms\n", delta);
2584                 } else
2585                         buf[cnt++] = '\n';
2586
2587                 j = iwl4965_get_prev_ieee_rate(i);
2588                 if (j == i)
2589                         break;
2590                 i = j;
2591         }
2592
2593         /* Display the average rate of all samples taken.
2594          *
2595          * NOTE:  We multiply # of samples by 2 since the IEEE measurement
2596          * added from iwl4965_rates is actually 2X the rate */
2597         if (samples)
2598                 cnt += sprintf(&buf[cnt],
2599                          "\nAverage rate is %3d.%02dMbs over last %4dms\n"
2600                          "%3d%% success (%d good packets over %d tries)\n",
2601                          success / (2 * samples), (success * 5 / samples) % 10,
2602                          max_time, good * 100 / samples, good, samples);
2603         else
2604                 cnt += sprintf(&buf[cnt], "\nAverage rate: 0Mbs\n");
2605
2606         cnt += sprintf(&buf[cnt], "\nrate scale type %d antenna %d "
2607                          "active_search %d rate index %d\n", lq_type, antenna,
2608                          lq_sta->search_better_tbl, sta->last_txrate);
2609
2610         sta_info_put(sta);
2611         return cnt;
2612 }
2613
2614 void iwl4965_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
2615 {
2616         struct iwl4965_priv *priv = hw->priv;
2617
2618         priv->lq_mngr.lq_ready = 1;
2619 }
2620
2621 void iwl4965_rate_control_register(struct ieee80211_hw *hw)
2622 {
2623         ieee80211_rate_control_register(&rs_ops);
2624 }
2625
2626 void iwl4965_rate_control_unregister(struct ieee80211_hw *hw)
2627 {
2628         ieee80211_rate_control_unregister(&rs_ops);
2629 }
2630