cd1bff590491dd0fb5179506c24136144421d9bc
[linux-2.6.git] / drivers / net / wireless / iwlwifi / iwl-agn-rs.c
1 /******************************************************************************
2  *
3  * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
17  *
18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  * Contact Information:
22  * 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
32 #include <linux/netdevice.h>
33 #include <linux/etherdevice.h>
34 #include <linux/delay.h>
35
36 #include <linux/workqueue.h>
37
38 #include "iwl-dev.h"
39 #include "iwl-sta.h"
40 #include "iwl-core.h"
41 #include "iwl-helpers.h"
42
43 #define RS_NAME "iwl-agn-rs"
44
45 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
46 #define IWL_NUMBER_TRY      1
47 #define IWL_HT_NUMBER_TRY   3
48
49 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
50 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
51 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
52
53 /* max time to accum history 2 seconds */
54 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
55
56 static u8 rs_ht_to_legacy[] = {
57         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
59         IWL_RATE_6M_INDEX,
60         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
61         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
62         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
63         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
64 };
65
66 static const u8 ant_toggle_lookup[] = {
67         /*ANT_NONE -> */ ANT_NONE,
68         /*ANT_A    -> */ ANT_B,
69         /*ANT_B    -> */ ANT_C,
70         /*ANT_AB   -> */ ANT_BC,
71         /*ANT_C    -> */ ANT_A,
72         /*ANT_AC   -> */ ANT_AB,
73         /*ANT_BC   -> */ ANT_AC,
74         /*ANT_ABC  -> */ ANT_ABC,
75 };
76
77 /**
78  * struct iwl_rate_scale_data -- tx success history for one rate
79  */
80 struct iwl_rate_scale_data {
81         u64 data;               /* bitmap of successful frames */
82         s32 success_counter;    /* number of frames successful */
83         s32 success_ratio;      /* per-cent * 128  */
84         s32 counter;            /* number of frames attempted */
85         s32 average_tpt;        /* success ratio * expected throughput */
86         unsigned long stamp;
87 };
88
89 /**
90  * struct iwl_scale_tbl_info -- tx params and success history for all rates
91  *
92  * There are two of these in struct iwl_lq_sta,
93  * one for "active", and one for "search".
94  */
95 struct iwl_scale_tbl_info {
96         enum iwl_table_type lq_type;
97         u8 ant_type;
98         u8 is_SGI;      /* 1 = short guard interval */
99         u8 is_fat;      /* 1 = 40 MHz channel width */
100         u8 is_dup;      /* 1 = duplicated data streams */
101         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
102         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
103         u32 current_rate;  /* rate_n_flags, uCode API format */
104         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
105 };
106
107 struct iwl_traffic_load {
108         unsigned long time_stamp;       /* age of the oldest statistics */
109         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
110                                                  * slice */
111         u32 total;                      /* total num of packets during the
112                                          * last TID_MAX_TIME_DIFF */
113         u8 queue_count;                 /* number of queues that has
114                                          * been used since the last cleanup */
115         u8 head;                        /* start of the circular buffer */
116 };
117
118 /**
119  * struct iwl_lq_sta -- driver's rate scaling private structure
120  *
121  * Pointer to this gets passed back and forth between driver and mac80211.
122  */
123 struct iwl_lq_sta {
124         u8 active_tbl;          /* index of active table, range 0-1 */
125         u8 enable_counter;      /* indicates HT mode */
126         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
127         u8 search_better_tbl;   /* 1: currently trying alternate mode */
128         s32 last_tpt;
129
130         /* The following determine when to search for a new mode */
131         u32 table_count_limit;
132         u32 max_failure_limit;  /* # failed frames before new search */
133         u32 max_success_limit;  /* # successful frames before new search */
134         u32 table_count;
135         u32 total_failed;       /* total failed frames, any/all rates */
136         u32 total_success;      /* total successful frames, any/all rates */
137         u32 flush_timer;        /* time staying in mode before new search */
138
139         u8 action_counter;      /* # mode-switch actions tried */
140         u8 is_green;
141         u8 is_dup;
142         enum ieee80211_band band;
143         u8 ibss_sta_added;
144
145         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
146         u32 supp_rates;
147         u16 active_legacy_rate;
148         u16 active_siso_rate;
149         u16 active_mimo2_rate;
150         u16 active_mimo3_rate;
151         u16 active_rate_basic;
152
153         struct iwl_link_quality_cmd lq;
154         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
155         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
156         u8 tx_agg_tid_en;
157 #ifdef CONFIG_MAC80211_DEBUGFS
158         struct dentry *rs_sta_dbgfs_scale_table_file;
159         struct dentry *rs_sta_dbgfs_stats_table_file;
160         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
161         u32 dbg_fixed_rate;
162 #endif
163         struct iwl_priv *drv;
164
165         /* used to be in sta_info */
166         int last_txrate_idx;
167 };
168
169 static void rs_rate_scale_perform(struct iwl_priv *priv,
170                                    struct ieee80211_hdr *hdr,
171                                    struct ieee80211_sta *sta,
172                                    struct iwl_lq_sta *lq_sta);
173 static void rs_fill_link_cmd(const struct iwl_priv *priv,
174                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
175
176
177 #ifdef CONFIG_MAC80211_DEBUGFS
178 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
179                              u32 *rate_n_flags, int index);
180 #else
181 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
182                              u32 *rate_n_flags, int index)
183 {}
184 #endif
185
186 /*
187  * Expected throughput metrics for following rates:
188  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
189  * "G" is the only table that supports CCK (the first 4 rates).
190  */
191 /*FIXME:RS:need to spearate tables for MIMO2/MIMO3*/
192 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
193         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
194 };
195
196 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
197         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
198 };
199
200 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
201         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
202 };
203
204 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
205         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
206 };
207
208 static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
209         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
210 };
211
212 static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
213         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
214 };
215
216 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
217         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
218 };
219
220 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
221         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
222 };
223
224 static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
225         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
226 };
227
228 static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
229         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
230 };
231
232 static inline u8 rs_extract_rate(u32 rate_n_flags)
233 {
234         return (u8)(rate_n_flags & 0xFF);
235 }
236
237 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
238 {
239         window->data = 0;
240         window->success_counter = 0;
241         window->success_ratio = IWL_INVALID_VALUE;
242         window->counter = 0;
243         window->average_tpt = IWL_INVALID_VALUE;
244         window->stamp = 0;
245 }
246
247 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
248 {
249         return (ant_type & valid_antenna) == ant_type;
250 }
251
252 /*
253  *      removes the old data from the statistics. All data that is older than
254  *      TID_MAX_TIME_DIFF, will be deleted.
255  */
256 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
257 {
258         /* The oldest age we want to keep */
259         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
260
261         while (tl->queue_count &&
262                (tl->time_stamp < oldest_time)) {
263                 tl->total -= tl->packet_count[tl->head];
264                 tl->packet_count[tl->head] = 0;
265                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
266                 tl->queue_count--;
267                 tl->head++;
268                 if (tl->head >= TID_QUEUE_MAX_SIZE)
269                         tl->head = 0;
270         }
271 }
272
273 /*
274  *      increment traffic load value for tid and also remove
275  *      any old values if passed the certain time period
276  */
277 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
278                            struct ieee80211_hdr *hdr)
279 {
280         u32 curr_time = jiffies_to_msecs(jiffies);
281         u32 time_diff;
282         s32 index;
283         struct iwl_traffic_load *tl = NULL;
284         __le16 fc = hdr->frame_control;
285         u8 tid;
286
287         if (ieee80211_is_data_qos(fc)) {
288                 u8 *qc = ieee80211_get_qos_ctl(hdr);
289                 tid = qc[0] & 0xf;
290         } else
291                 return MAX_TID_COUNT;
292
293         tl = &lq_data->load[tid];
294
295         curr_time -= curr_time % TID_ROUND_VALUE;
296
297         /* Happens only for the first packet. Initialize the data */
298         if (!(tl->queue_count)) {
299                 tl->total = 1;
300                 tl->time_stamp = curr_time;
301                 tl->queue_count = 1;
302                 tl->head = 0;
303                 tl->packet_count[0] = 1;
304                 return MAX_TID_COUNT;
305         }
306
307         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
308         index = time_diff / TID_QUEUE_CELL_SPACING;
309
310         /* The history is too long: remove data that is older than */
311         /* TID_MAX_TIME_DIFF */
312         if (index >= TID_QUEUE_MAX_SIZE)
313                 rs_tl_rm_old_stats(tl, curr_time);
314
315         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
316         tl->packet_count[index] = tl->packet_count[index] + 1;
317         tl->total = tl->total + 1;
318
319         if ((index + 1) > tl->queue_count)
320                 tl->queue_count = index + 1;
321
322         return tid;
323 }
324
325 /*
326         get the traffic load value for tid
327 */
328 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
329 {
330         u32 curr_time = jiffies_to_msecs(jiffies);
331         u32 time_diff;
332         s32 index;
333         struct iwl_traffic_load *tl = NULL;
334
335         if (tid >= TID_MAX_LOAD_COUNT)
336                 return 0;
337
338         tl = &(lq_data->load[tid]);
339
340         curr_time -= curr_time % TID_ROUND_VALUE;
341
342         if (!(tl->queue_count))
343                 return 0;
344
345         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
346         index = time_diff / TID_QUEUE_CELL_SPACING;
347
348         /* The history is too long: remove data that is older than */
349         /* TID_MAX_TIME_DIFF */
350         if (index >= TID_QUEUE_MAX_SIZE)
351                 rs_tl_rm_old_stats(tl, curr_time);
352
353         return tl->total;
354 }
355
356 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
357                                       struct iwl_lq_sta *lq_data, u8 tid,
358                                       struct ieee80211_sta *sta)
359 {
360         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
361                 IWL_DEBUG_HT("Starting Tx agg: STA: %pM tid: %d\n",
362                                 sta->addr, tid);
363                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
364         }
365 }
366
367 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
368                               struct iwl_lq_sta *lq_data,
369                               struct ieee80211_sta *sta)
370 {
371         if ((tid < TID_MAX_LOAD_COUNT))
372                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
373         else if (tid == IWL_AGG_ALL_TID)
374                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
375                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
376 }
377
378 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
379 {
380         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
381                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
382                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
383 }
384
385 /**
386  * rs_collect_tx_data - Update the success/failure sliding window
387  *
388  * We keep a sliding window of the last 62 packets transmitted
389  * at this rate.  window->data contains the bitmask of successful
390  * packets.
391  */
392 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
393                               int scale_index, s32 tpt, int retries,
394                               int successes)
395 {
396         struct iwl_rate_scale_data *window = NULL;
397         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
398         s32 fail_count;
399
400         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
401                 return -EINVAL;
402
403         /* Select data for current tx bit rate */
404         window = &(windows[scale_index]);
405
406         /*
407          * Keep track of only the latest 62 tx frame attempts in this rate's
408          * history window; anything older isn't really relevant any more.
409          * If we have filled up the sliding window, drop the oldest attempt;
410          * if the oldest attempt (highest bit in bitmap) shows "success",
411          * subtract "1" from the success counter (this is the main reason
412          * we keep these bitmaps!).
413          */
414         while (retries > 0) {
415                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
416
417                         /* remove earliest */
418                         window->counter = IWL_RATE_MAX_WINDOW - 1;
419
420                         if (window->data & mask) {
421                                 window->data &= ~mask;
422                                 window->success_counter--;
423                         }
424                 }
425
426                 /* Increment frames-attempted counter */
427                 window->counter++;
428
429                 /* Shift bitmap by one frame (throw away oldest history),
430                  * OR in "1", and increment "success" if this
431                  * frame was successful. */
432                 window->data <<= 1;
433                 if (successes > 0) {
434                         window->success_counter++;
435                         window->data |= 0x1;
436                         successes--;
437                 }
438
439                 retries--;
440         }
441
442         /* Calculate current success ratio, avoid divide-by-0! */
443         if (window->counter > 0)
444                 window->success_ratio = 128 * (100 * window->success_counter)
445                                         / window->counter;
446         else
447                 window->success_ratio = IWL_INVALID_VALUE;
448
449         fail_count = window->counter - window->success_counter;
450
451         /* Calculate average throughput, if we have enough history. */
452         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
453             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
454                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
455         else
456                 window->average_tpt = IWL_INVALID_VALUE;
457
458         /* Tag this window as having been updated */
459         window->stamp = jiffies;
460
461         return 0;
462 }
463
464 /*
465  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
466  */
467 /* FIXME:RS:remove this function and put the flags statically in the table */
468 static u32 rate_n_flags_from_tbl(struct iwl_scale_tbl_info *tbl,
469                                        int index, u8 use_green)
470 {
471         u32 rate_n_flags = 0;
472
473         if (is_legacy(tbl->lq_type)) {
474                 rate_n_flags = iwl_rates[index].plcp;
475                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
476                         rate_n_flags |= RATE_MCS_CCK_MSK;
477
478         } else if (is_Ht(tbl->lq_type)) {
479                 if (index > IWL_LAST_OFDM_RATE) {
480                         IWL_ERROR("invalid HT rate index %d\n", index);
481                         index = IWL_LAST_OFDM_RATE;
482                 }
483                 rate_n_flags = RATE_MCS_HT_MSK;
484
485                 if (is_siso(tbl->lq_type))
486                         rate_n_flags |= iwl_rates[index].plcp_siso;
487                 else if (is_mimo2(tbl->lq_type))
488                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
489                 else
490                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
491         } else {
492                 IWL_ERROR("Invalid tbl->lq_type %d\n", tbl->lq_type);
493         }
494
495         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
496                                                      RATE_MCS_ANT_ABC_MSK);
497
498         if (is_Ht(tbl->lq_type)) {
499                 if (tbl->is_fat) {
500                         if (tbl->is_dup)
501                                 rate_n_flags |= RATE_MCS_DUP_MSK;
502                         else
503                                 rate_n_flags |= RATE_MCS_FAT_MSK;
504                 }
505                 if (tbl->is_SGI)
506                         rate_n_flags |= RATE_MCS_SGI_MSK;
507
508                 if (use_green) {
509                         rate_n_flags |= RATE_MCS_GF_MSK;
510                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
511                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
512                                 IWL_ERROR("GF was set with SGI:SISO\n");
513                         }
514                 }
515         }
516         return rate_n_flags;
517 }
518
519 /*
520  * Interpret uCode API's rate_n_flags format,
521  * fill "search" or "active" tx mode table.
522  */
523 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
524                                     enum ieee80211_band band,
525                                     struct iwl_scale_tbl_info *tbl,
526                                     int *rate_idx)
527 {
528         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
529         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
530         u8 mcs;
531
532         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
533
534         if (*rate_idx  == IWL_RATE_INVALID) {
535                 *rate_idx = -1;
536                 return -EINVAL;
537         }
538         tbl->is_SGI = 0;        /* default legacy setup */
539         tbl->is_fat = 0;
540         tbl->is_dup = 0;
541         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
542         tbl->lq_type = LQ_NONE;
543
544         /* legacy rate format */
545         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
546                 if (num_of_ant == 1) {
547                         if (band == IEEE80211_BAND_5GHZ)
548                                 tbl->lq_type = LQ_A;
549                         else
550                                 tbl->lq_type = LQ_G;
551                 }
552         /* HT rate format */
553         } else {
554                 if (rate_n_flags & RATE_MCS_SGI_MSK)
555                         tbl->is_SGI = 1;
556
557                 if ((rate_n_flags & RATE_MCS_FAT_MSK) ||
558                     (rate_n_flags & RATE_MCS_DUP_MSK))
559                         tbl->is_fat = 1;
560
561                 if (rate_n_flags & RATE_MCS_DUP_MSK)
562                         tbl->is_dup = 1;
563
564                 mcs = rs_extract_rate(rate_n_flags);
565
566                 /* SISO */
567                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
568                         if (num_of_ant == 1)
569                                 tbl->lq_type = LQ_SISO; /*else NONE*/
570                 /* MIMO2 */
571                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
572                         if (num_of_ant == 2)
573                                 tbl->lq_type = LQ_MIMO2;
574                 /* MIMO3 */
575                 } else {
576                         if (num_of_ant == 3)
577                                 tbl->lq_type = LQ_MIMO3;
578                 }
579         }
580         return 0;
581 }
582
583 /* switch to another antenna/antennas and return 1 */
584 /* if no other valid antenna found, return 0 */
585 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
586                              struct iwl_scale_tbl_info *tbl)
587 {
588         u8 new_ant_type;
589
590         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
591                 return 0;
592
593         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
594                 return 0;
595
596         new_ant_type = ant_toggle_lookup[tbl->ant_type];
597
598         while ((new_ant_type != tbl->ant_type) &&
599                !rs_is_valid_ant(valid_ant, new_ant_type))
600                 new_ant_type = ant_toggle_lookup[new_ant_type];
601
602         if (new_ant_type == tbl->ant_type)
603                 return 0;
604
605         tbl->ant_type = new_ant_type;
606         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
607         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
608         return 1;
609 }
610
611 /* FIXME:RS: in 4965 we don't use greenfield at all */
612 /* FIXME:RS: don't use greenfield for now in TX */
613 #if 0
614 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
615 {
616         return (conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
617                 priv->current_ht_config.is_green_field &&
618                 !priv->current_ht_config.non_GF_STA_present;
619 }
620 #endif
621 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
622 {
623         return 0;
624 }
625
626 /**
627  * rs_get_supported_rates - get the available rates
628  *
629  * if management frame or broadcast frame only return
630  * basic available rates.
631  *
632  */
633 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
634                                   struct ieee80211_hdr *hdr,
635                                   enum iwl_table_type rate_type)
636 {
637         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
638             lq_sta->active_rate_basic)
639                 return lq_sta->active_rate_basic;
640
641         if (is_legacy(rate_type)) {
642                 return lq_sta->active_legacy_rate;
643         } else {
644                 if (is_siso(rate_type))
645                         return lq_sta->active_siso_rate;
646                 else if (is_mimo2(rate_type))
647                         return lq_sta->active_mimo2_rate;
648                 else
649                         return lq_sta->active_mimo3_rate;
650         }
651 }
652
653 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
654                                 int rate_type)
655 {
656         u8 high = IWL_RATE_INVALID;
657         u8 low = IWL_RATE_INVALID;
658
659         /* 802.11A or ht walks to the next literal adjacent rate in
660          * the rate table */
661         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
662                 int i;
663                 u32 mask;
664
665                 /* Find the previous rate that is in the rate mask */
666                 i = index - 1;
667                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
668                         if (rate_mask & mask) {
669                                 low = i;
670                                 break;
671                         }
672                 }
673
674                 /* Find the next rate that is in the rate mask */
675                 i = index + 1;
676                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
677                         if (rate_mask & mask) {
678                                 high = i;
679                                 break;
680                         }
681                 }
682
683                 return (high << 8) | low;
684         }
685
686         low = index;
687         while (low != IWL_RATE_INVALID) {
688                 low = iwl_rates[low].prev_rs;
689                 if (low == IWL_RATE_INVALID)
690                         break;
691                 if (rate_mask & (1 << low))
692                         break;
693                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
694         }
695
696         high = index;
697         while (high != IWL_RATE_INVALID) {
698                 high = iwl_rates[high].next_rs;
699                 if (high == IWL_RATE_INVALID)
700                         break;
701                 if (rate_mask & (1 << high))
702                         break;
703                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
704         }
705
706         return (high << 8) | low;
707 }
708
709 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
710                              struct iwl_scale_tbl_info *tbl,
711                              u8 scale_index, u8 ht_possible)
712 {
713         s32 low;
714         u16 rate_mask;
715         u16 high_low;
716         u8 switch_to_legacy = 0;
717         u8 is_green = lq_sta->is_green;
718
719         /* check if we need to switch from HT to legacy rates.
720          * assumption is that mandatory rates (1Mbps or 6Mbps)
721          * are always supported (spec demand) */
722         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
723                 switch_to_legacy = 1;
724                 scale_index = rs_ht_to_legacy[scale_index];
725                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
726                         tbl->lq_type = LQ_A;
727                 else
728                         tbl->lq_type = LQ_G;
729
730                 if (num_of_ant(tbl->ant_type) > 1)
731                         tbl->ant_type = ANT_A;/*FIXME:RS*/
732
733                 tbl->is_fat = 0;
734                 tbl->is_SGI = 0;
735         }
736
737         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
738
739         /* Mask with station rate restriction */
740         if (is_legacy(tbl->lq_type)) {
741                 /* supp_rates has no CCK bits in A mode */
742                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
743                         rate_mask  = (u16)(rate_mask &
744                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
745                 else
746                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
747         }
748
749         /* If we switched from HT to legacy, check current rate */
750         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
751                 low = scale_index;
752                 goto out;
753         }
754
755         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
756                                         tbl->lq_type);
757         low = high_low & 0xff;
758
759         if (low == IWL_RATE_INVALID)
760                 low = scale_index;
761
762 out:
763         return rate_n_flags_from_tbl(tbl, low, is_green);
764 }
765
766 /*
767  * mac80211 sends us Tx status
768  */
769 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
770                          struct ieee80211_sta *sta, void *priv_sta,
771                          struct sk_buff *skb)
772 {
773         int status;
774         u8 retries;
775         int rs_index, index = 0;
776         struct iwl_lq_sta *lq_sta;
777         struct iwl_link_quality_cmd *table;
778         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
779         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
780         struct ieee80211_hw *hw = priv->hw;
781         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
782         struct iwl_rate_scale_data *window = NULL;
783         struct iwl_rate_scale_data *search_win = NULL;
784         u32 tx_rate;
785         struct iwl_scale_tbl_info tbl_type;
786         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
787         u8 active_index = 0;
788         __le16 fc = hdr->frame_control;
789         s32 tpt = 0;
790
791         IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
792
793         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1))
794                 return;
795
796         /* This packet was aggregated but doesn't carry rate scale info */
797         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
798             !(info->flags & IEEE80211_TX_STAT_AMPDU))
799                 return;
800
801         retries = info->status.retry_count;
802
803         if (retries > 15)
804                 retries = 15;
805
806         lq_sta = (struct iwl_lq_sta *)priv_sta;
807
808         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
809             !lq_sta->ibss_sta_added)
810                 goto out;
811
812         table = &lq_sta->lq;
813         active_index = lq_sta->active_tbl;
814
815         curr_tbl = &(lq_sta->lq_info[active_index]);
816         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
817         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
818         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
819
820         /*
821          * Ignore this Tx frame response if its initial rate doesn't match
822          * that of latest Link Quality command.  There may be stragglers
823          * from a previous Link Quality command, but we're no longer interested
824          * in those; they're either from the "active" mode while we're trying
825          * to check "search" mode, or a prior "search" mode after we've moved
826          * to a new "search" mode (which might become the new "active" mode).
827          */
828         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
829         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
830         if (priv->band == IEEE80211_BAND_5GHZ)
831                 rs_index -= IWL_FIRST_OFDM_RATE;
832
833         if ((info->tx_rate_idx < 0) ||
834             (tbl_type.is_SGI ^
835                 !!(info->flags & IEEE80211_TX_CTL_SHORT_GI)) ||
836             (tbl_type.is_fat ^
837                 !!(info->flags & IEEE80211_TX_CTL_40_MHZ_WIDTH)) ||
838             (tbl_type.is_dup ^
839                 !!(info->flags & IEEE80211_TX_CTL_DUP_DATA)) ||
840             (tbl_type.ant_type ^ info->antenna_sel_tx) ||
841             (!!(tx_rate & RATE_MCS_HT_MSK) ^
842                 !!(info->flags & IEEE80211_TX_CTL_OFDM_HT)) ||
843             (!!(tx_rate & RATE_MCS_GF_MSK) ^
844                 !!(info->flags & IEEE80211_TX_CTL_GREEN_FIELD)) ||
845             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
846              hw->wiphy->bands[info->band]->bitrates[info->tx_rate_idx].bitrate)) {
847                 IWL_DEBUG_RATE("initial rate does not match 0x%x\n", tx_rate);
848                 goto out;
849         }
850
851         /* Update frame history window with "failure" for each Tx retry. */
852         while (retries) {
853                 /* Look up the rate and other info used for each tx attempt.
854                  * Each tx attempt steps one entry deeper in the rate table. */
855                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
856                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
857                                           &tbl_type, &rs_index);
858
859                 /* If type matches "search" table,
860                  * add failure to "search" history */
861                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
862                     (tbl_type.ant_type == search_tbl->ant_type) &&
863                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
864                         if (search_tbl->expected_tpt)
865                                 tpt = search_tbl->expected_tpt[rs_index];
866                         else
867                                 tpt = 0;
868                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
869
870                 /* Else if type matches "current/active" table,
871                  * add failure to "current/active" history */
872                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
873                            (tbl_type.ant_type == curr_tbl->ant_type) &&
874                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
875                         if (curr_tbl->expected_tpt)
876                                 tpt = curr_tbl->expected_tpt[rs_index];
877                         else
878                                 tpt = 0;
879                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
880                 }
881
882                 /* If not searching for a new mode, increment failed counter
883                  * ... this helps determine when to start searching again */
884                 if (lq_sta->stay_in_tbl)
885                         lq_sta->total_failed++;
886                 --retries;
887                 index++;
888
889         }
890
891         /*
892          * Find (by rate) the history window to update with final Tx attempt;
893          * if Tx was successful first try, use original rate,
894          * else look up the rate that was, finally, successful.
895          */
896         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
897         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
898
899         /* Update frame history window with "success" if Tx got ACKed ... */
900         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
901
902         /* If type matches "search" table,
903          * add final tx status to "search" history */
904         if ((tbl_type.lq_type == search_tbl->lq_type) &&
905             (tbl_type.ant_type == search_tbl->ant_type) &&
906             (tbl_type.is_SGI == search_tbl->is_SGI)) {
907                 if (search_tbl->expected_tpt)
908                         tpt = search_tbl->expected_tpt[rs_index];
909                 else
910                         tpt = 0;
911                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
912                         rs_collect_tx_data(search_win, rs_index, tpt,
913                                            info->status.ampdu_ack_len,
914                                            info->status.ampdu_ack_map);
915                 else
916                         rs_collect_tx_data(search_win, rs_index, tpt,
917                                            1, status);
918         /* Else if type matches "current/active" table,
919          * add final tx status to "current/active" history */
920         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
921                    (tbl_type.ant_type == curr_tbl->ant_type) &&
922                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
923                 if (curr_tbl->expected_tpt)
924                         tpt = curr_tbl->expected_tpt[rs_index];
925                 else
926                         tpt = 0;
927                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
928                         rs_collect_tx_data(window, rs_index, tpt,
929                                            info->status.ampdu_ack_len,
930                                            info->status.ampdu_ack_map);
931                 else
932                         rs_collect_tx_data(window, rs_index, tpt,
933                                            1, status);
934         }
935
936         /* If not searching for new mode, increment success/failed counter
937          * ... these help determine when to start searching again */
938         if (lq_sta->stay_in_tbl) {
939                 if (info->flags & IEEE80211_TX_CTL_AMPDU) {
940                         lq_sta->total_success += info->status.ampdu_ack_map;
941                         lq_sta->total_failed +=
942                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
943                 } else {
944                         if (status)
945                                 lq_sta->total_success++;
946                         else
947                                 lq_sta->total_failed++;
948                 }
949         }
950
951         /* See if there's a better rate or modulation mode to try. */
952         rs_rate_scale_perform(priv, hdr, sta, lq_sta);
953 out:
954         return;
955 }
956
957 /*
958  * Begin a period of staying with a selected modulation mode.
959  * Set "stay_in_tbl" flag to prevent any mode switches.
960  * Set frame tx success limits according to legacy vs. high-throughput,
961  * and reset overall (spanning all rates) tx success history statistics.
962  * These control how long we stay using same modulation mode before
963  * searching for a new mode.
964  */
965 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
966                                  struct iwl_lq_sta *lq_sta)
967 {
968         IWL_DEBUG_RATE("we are staying in the same table\n");
969         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
970         if (is_legacy) {
971                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
972                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
973                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
974         } else {
975                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
976                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
977                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
978         }
979         lq_sta->table_count = 0;
980         lq_sta->total_failed = 0;
981         lq_sta->total_success = 0;
982 }
983
984 /*
985  * Find correct throughput table for given mode of modulation
986  */
987 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
988                                       struct iwl_scale_tbl_info *tbl)
989 {
990         if (is_legacy(tbl->lq_type)) {
991                 if (!is_a_band(tbl->lq_type))
992                         tbl->expected_tpt = expected_tpt_G;
993                 else
994                         tbl->expected_tpt = expected_tpt_A;
995         } else if (is_siso(tbl->lq_type)) {
996                 if (tbl->is_fat && !lq_sta->is_dup)
997                         if (tbl->is_SGI)
998                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
999                         else
1000                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1001                 else if (tbl->is_SGI)
1002                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1003                 else
1004                         tbl->expected_tpt = expected_tpt_siso20MHz;
1005
1006         } else if (is_mimo(tbl->lq_type)) { /* FIXME:need to separate mimo2/3 */
1007                 if (tbl->is_fat && !lq_sta->is_dup)
1008                         if (tbl->is_SGI)
1009                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
1010                         else
1011                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
1012                 else if (tbl->is_SGI)
1013                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
1014                 else
1015                         tbl->expected_tpt = expected_tpt_mimo20MHz;
1016         } else
1017                 tbl->expected_tpt = expected_tpt_G;
1018 }
1019
1020 /*
1021  * Find starting rate for new "search" high-throughput mode of modulation.
1022  * Goal is to find lowest expected rate (under perfect conditions) that is
1023  * above the current measured throughput of "active" mode, to give new mode
1024  * a fair chance to prove itself without too many challenges.
1025  *
1026  * This gets called when transitioning to more aggressive modulation
1027  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1028  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1029  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1030  * bit rate will typically need to increase, but not if performance was bad.
1031  */
1032 static s32 rs_get_best_rate(struct iwl_priv *priv,
1033                             struct iwl_lq_sta *lq_sta,
1034                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1035                             u16 rate_mask, s8 index)
1036 {
1037         /* "active" values */
1038         struct iwl_scale_tbl_info *active_tbl =
1039             &(lq_sta->lq_info[lq_sta->active_tbl]);
1040         s32 active_sr = active_tbl->win[index].success_ratio;
1041         s32 active_tpt = active_tbl->expected_tpt[index];
1042
1043         /* expected "search" throughput */
1044         s32 *tpt_tbl = tbl->expected_tpt;
1045
1046         s32 new_rate, high, low, start_hi;
1047         u16 high_low;
1048         s8 rate = index;
1049
1050         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1051
1052         for (; ;) {
1053                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1054                                                 tbl->lq_type);
1055
1056                 low = high_low & 0xff;
1057                 high = (high_low >> 8) & 0xff;
1058
1059                 /*
1060                  * Lower the "search" bit rate, to give new "search" mode
1061                  * approximately the same throughput as "active" if:
1062                  *
1063                  * 1) "Active" mode has been working modestly well (but not
1064                  *    great), and expected "search" throughput (under perfect
1065                  *    conditions) at candidate rate is above the actual
1066                  *    measured "active" throughput (but less than expected
1067                  *    "active" throughput under perfect conditions).
1068                  * OR
1069                  * 2) "Active" mode has been working perfectly or very well
1070                  *    and expected "search" throughput (under perfect
1071                  *    conditions) at candidate rate is above expected
1072                  *    "active" throughput (under perfect conditions).
1073                  */
1074                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1075                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1076                       (active_sr <= IWL_RATE_HIGH_TH) &&
1077                       (tpt_tbl[rate] <= active_tpt))) ||
1078                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1079                      (tpt_tbl[rate] > active_tpt))) {
1080
1081                         /* (2nd or later pass)
1082                          * If we've already tried to raise the rate, and are
1083                          * now trying to lower it, use the higher rate. */
1084                         if (start_hi != IWL_RATE_INVALID) {
1085                                 new_rate = start_hi;
1086                                 break;
1087                         }
1088
1089                         new_rate = rate;
1090
1091                         /* Loop again with lower rate */
1092                         if (low != IWL_RATE_INVALID)
1093                                 rate = low;
1094
1095                         /* Lower rate not available, use the original */
1096                         else
1097                                 break;
1098
1099                 /* Else try to raise the "search" rate to match "active" */
1100                 } else {
1101                         /* (2nd or later pass)
1102                          * If we've already tried to lower the rate, and are
1103                          * now trying to raise it, use the lower rate. */
1104                         if (new_rate != IWL_RATE_INVALID)
1105                                 break;
1106
1107                         /* Loop again with higher rate */
1108                         else if (high != IWL_RATE_INVALID) {
1109                                 start_hi = high;
1110                                 rate = high;
1111
1112                         /* Higher rate not available, use the original */
1113                         } else {
1114                                 new_rate = rate;
1115                                 break;
1116                         }
1117                 }
1118         }
1119
1120         return new_rate;
1121 }
1122
1123 /*
1124  * Set up search table for MIMO
1125  */
1126 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1127                              struct iwl_lq_sta *lq_sta,
1128                              struct ieee80211_conf *conf,
1129                              struct ieee80211_sta *sta,
1130                              struct iwl_scale_tbl_info *tbl, int index)
1131 {
1132         u16 rate_mask;
1133         s32 rate;
1134         s8 is_green = lq_sta->is_green;
1135
1136         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1137             !sta->ht_cap.ht_supported)
1138                 return -1;
1139
1140         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1141                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1142                 return -1;
1143
1144         /* Need both Tx chains/antennas to support MIMO */
1145         if (priv->hw_params.tx_chains_num < 2)
1146                 return -1;
1147
1148         IWL_DEBUG_RATE("LQ: try to switch to MIMO2\n");
1149
1150         tbl->lq_type = LQ_MIMO2;
1151         tbl->is_dup = lq_sta->is_dup;
1152         tbl->action = 0;
1153         rate_mask = lq_sta->active_mimo2_rate;
1154
1155         if (priv->current_ht_config.supported_chan_width
1156                                         == IWL_CHANNEL_WIDTH_40MHZ)
1157                 tbl->is_fat = 1;
1158         else
1159                 tbl->is_fat = 0;
1160
1161         /* FIXME: - don't toggle SGI here
1162         if (tbl->is_fat) {
1163                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1164                         tbl->is_SGI = 1;
1165                 else
1166                         tbl->is_SGI = 0;
1167         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1168                 tbl->is_SGI = 1;
1169         else
1170                 tbl->is_SGI = 0;
1171         */
1172
1173         rs_set_expected_tpt_table(lq_sta, tbl);
1174
1175         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1176
1177         IWL_DEBUG_RATE("LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1178
1179         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1180                 IWL_DEBUG_RATE("Can't switch with index %d rate mask %x\n",
1181                                                 rate, rate_mask);
1182                 return -1;
1183         }
1184         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1185
1186         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1187                      tbl->current_rate, is_green);
1188         return 0;
1189 }
1190
1191 /*
1192  * Set up search table for SISO
1193  */
1194 static int rs_switch_to_siso(struct iwl_priv *priv,
1195                              struct iwl_lq_sta *lq_sta,
1196                              struct ieee80211_conf *conf,
1197                              struct ieee80211_sta *sta,
1198                              struct iwl_scale_tbl_info *tbl, int index)
1199 {
1200         u16 rate_mask;
1201         u8 is_green = lq_sta->is_green;
1202         s32 rate;
1203
1204         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1205             !sta->ht_cap.ht_supported)
1206                 return -1;
1207
1208         IWL_DEBUG_RATE("LQ: try to switch to SISO\n");
1209
1210         tbl->is_dup = lq_sta->is_dup;
1211         tbl->lq_type = LQ_SISO;
1212         tbl->action = 0;
1213         rate_mask = lq_sta->active_siso_rate;
1214
1215         if (priv->current_ht_config.supported_chan_width
1216             == IWL_CHANNEL_WIDTH_40MHZ)
1217                 tbl->is_fat = 1;
1218         else
1219                 tbl->is_fat = 0;
1220
1221         /* FIXME: - don't toggle SGI here
1222         if (tbl->is_fat) {
1223                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1224                         tbl->is_SGI = 1;
1225                 else
1226                         tbl->is_SGI = 0;
1227         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1228                 tbl->is_SGI = 1;
1229         else
1230                 tbl->is_SGI = 0;
1231         */
1232
1233         if (is_green)
1234                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1235
1236         rs_set_expected_tpt_table(lq_sta, tbl);
1237         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1238
1239         IWL_DEBUG_RATE("LQ: get best rate %d mask %X\n", rate, rate_mask);
1240         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1241                 IWL_DEBUG_RATE("can not switch with index %d rate mask %x\n",
1242                              rate, rate_mask);
1243                 return -1;
1244         }
1245         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1246         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1247                      tbl->current_rate, is_green);
1248         return 0;
1249 }
1250
1251 /*
1252  * Try to switch to new modulation mode from legacy
1253  */
1254 static int rs_move_legacy_other(struct iwl_priv *priv,
1255                                 struct iwl_lq_sta *lq_sta,
1256                                 struct ieee80211_conf *conf,
1257                                 struct ieee80211_sta *sta,
1258                                 int index)
1259 {
1260         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1261         struct iwl_scale_tbl_info *search_tbl =
1262                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1263         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1264         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1265                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1266         u8 start_action = tbl->action;
1267         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1268         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1269         int ret = 0;
1270
1271         for (; ;) {
1272                 switch (tbl->action) {
1273                 case IWL_LEGACY_SWITCH_ANTENNA1:
1274                 case IWL_LEGACY_SWITCH_ANTENNA2:
1275                         IWL_DEBUG_RATE("LQ: Legacy toggle Antenna\n");
1276
1277                         lq_sta->action_counter++;
1278
1279                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1280                                                         tx_chains_num <= 1) ||
1281                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1282                                                         tx_chains_num <= 2))
1283                                 break;
1284
1285                         /* Don't change antenna if success has been great */
1286                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1287                                 break;
1288
1289                         /* Set up search table to try other antenna */
1290                         memcpy(search_tbl, tbl, sz);
1291
1292                         if (rs_toggle_antenna(valid_tx_ant,
1293                                 &search_tbl->current_rate, search_tbl)) {
1294                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1295                                 goto out;
1296                         }
1297                         break;
1298                 case IWL_LEGACY_SWITCH_SISO:
1299                         IWL_DEBUG_RATE("LQ: Legacy switch to SISO\n");
1300
1301                         /* Set up search table to try SISO */
1302                         memcpy(search_tbl, tbl, sz);
1303                         search_tbl->is_SGI = 0;
1304                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1305                                                  search_tbl, index);
1306                         if (!ret) {
1307                                 lq_sta->action_counter = 0;
1308                                 goto out;
1309                         }
1310
1311                         break;
1312                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1313                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1314                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1315                         IWL_DEBUG_RATE("LQ: Legacy switch to MIMO2\n");
1316
1317                         /* Set up search table to try MIMO */
1318                         memcpy(search_tbl, tbl, sz);
1319                         search_tbl->is_SGI = 0;
1320
1321                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1322                                 search_tbl->ant_type = ANT_AB;
1323                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1324                                 search_tbl->ant_type = ANT_AC;
1325                         else
1326                                 search_tbl->ant_type = ANT_BC;
1327
1328                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1329                                 break;
1330
1331                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1332                                                  search_tbl, index);
1333                         if (!ret) {
1334                                 lq_sta->action_counter = 0;
1335                                 goto out;
1336                         }
1337                         break;
1338                 }
1339                 tbl->action++;
1340                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1341                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1342
1343                 if (tbl->action == start_action)
1344                         break;
1345
1346         }
1347         search_tbl->lq_type = LQ_NONE;
1348         return 0;
1349
1350 out:
1351         lq_sta->search_better_tbl = 1;
1352         tbl->action++;
1353         if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1354                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1355         return 0;
1356
1357 }
1358
1359 /*
1360  * Try to switch to new modulation mode from SISO
1361  */
1362 static int rs_move_siso_to_other(struct iwl_priv *priv,
1363                                  struct iwl_lq_sta *lq_sta,
1364                                  struct ieee80211_conf *conf,
1365                                  struct ieee80211_sta *sta, int index)
1366 {
1367         u8 is_green = lq_sta->is_green;
1368         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1369         struct iwl_scale_tbl_info *search_tbl =
1370                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1371         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1372         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1373                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1374         u8 start_action = tbl->action;
1375         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1376         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1377         int ret;
1378
1379         for (;;) {
1380                 lq_sta->action_counter++;
1381                 switch (tbl->action) {
1382                 case IWL_SISO_SWITCH_ANTENNA1:
1383                 case IWL_SISO_SWITCH_ANTENNA2:
1384                         IWL_DEBUG_RATE("LQ: SISO toggle Antenna\n");
1385
1386                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1387                                                         tx_chains_num <= 1) ||
1388                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1389                                                         tx_chains_num <= 2))
1390                                 break;
1391
1392                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1393                                 break;
1394
1395                         memcpy(search_tbl, tbl, sz);
1396                         if (rs_toggle_antenna(valid_tx_ant,
1397                                        &search_tbl->current_rate, search_tbl))
1398                                 goto out;
1399                         break;
1400                 case IWL_SISO_SWITCH_MIMO2_AB:
1401                 case IWL_SISO_SWITCH_MIMO2_AC:
1402                 case IWL_SISO_SWITCH_MIMO2_BC:
1403                         IWL_DEBUG_RATE("LQ: SISO switch to MIMO2\n");
1404                         memcpy(search_tbl, tbl, sz);
1405                         search_tbl->is_SGI = 0;
1406
1407                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1408                                 search_tbl->ant_type = ANT_AB;
1409                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1410                                 search_tbl->ant_type = ANT_AC;
1411                         else
1412                                 search_tbl->ant_type = ANT_BC;
1413
1414                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1415                                 break;
1416
1417                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1418                                                  search_tbl, index);
1419                         if (!ret)
1420                                 goto out;
1421                         break;
1422                 case IWL_SISO_SWITCH_GI:
1423                         if (!tbl->is_fat &&
1424                                 !(priv->current_ht_config.sgf &
1425                                                 HT_SHORT_GI_20MHZ))
1426                                 break;
1427                         if (tbl->is_fat &&
1428                                 !(priv->current_ht_config.sgf &
1429                                                 HT_SHORT_GI_40MHZ))
1430                                 break;
1431
1432                         IWL_DEBUG_RATE("LQ: SISO toggle SGI/NGI\n");
1433
1434                         memcpy(search_tbl, tbl, sz);
1435                         if (is_green) {
1436                                 if (!tbl->is_SGI)
1437                                         break;
1438                                 else
1439                                         IWL_ERROR("SGI was set in GF+SISO\n");
1440                         }
1441                         search_tbl->is_SGI = !tbl->is_SGI;
1442                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1443                         if (tbl->is_SGI) {
1444                                 s32 tpt = lq_sta->last_tpt / 100;
1445                                 if (tpt >= search_tbl->expected_tpt[index])
1446                                         break;
1447                         }
1448                         search_tbl->current_rate = rate_n_flags_from_tbl(
1449                                                 search_tbl, index, is_green);
1450                         goto out;
1451                 }
1452                 tbl->action++;
1453                 if (tbl->action > IWL_SISO_SWITCH_GI)
1454                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1455
1456                 if (tbl->action == start_action)
1457                         break;
1458         }
1459         search_tbl->lq_type = LQ_NONE;
1460         return 0;
1461
1462  out:
1463         lq_sta->search_better_tbl = 1;
1464         tbl->action++;
1465         if (tbl->action > IWL_SISO_SWITCH_GI)
1466                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1467         return 0;
1468 }
1469
1470 /*
1471  * Try to switch to new modulation mode from MIMO
1472  */
1473 static int rs_move_mimo_to_other(struct iwl_priv *priv,
1474                                  struct iwl_lq_sta *lq_sta,
1475                                  struct ieee80211_conf *conf,
1476                                  struct ieee80211_sta *sta, int index)
1477 {
1478         s8 is_green = lq_sta->is_green;
1479         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1480         struct iwl_scale_tbl_info *search_tbl =
1481                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1482         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1483         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1484                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1485         u8 start_action = tbl->action;
1486         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1487         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1488         int ret;
1489
1490         for (;;) {
1491                 lq_sta->action_counter++;
1492                 switch (tbl->action) {
1493                 case IWL_MIMO2_SWITCH_ANTENNA1:
1494                 case IWL_MIMO2_SWITCH_ANTENNA2:
1495                         IWL_DEBUG_RATE("LQ: MIMO toggle Antennas\n");
1496
1497                         if (tx_chains_num <= 2)
1498                                 break;
1499
1500                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1501                                 break;
1502
1503                         memcpy(search_tbl, tbl, sz);
1504                         if (rs_toggle_antenna(valid_tx_ant,
1505                                        &search_tbl->current_rate, search_tbl))
1506                                 goto out;
1507                         break;
1508                 case IWL_MIMO2_SWITCH_SISO_A:
1509                 case IWL_MIMO2_SWITCH_SISO_B:
1510                 case IWL_MIMO2_SWITCH_SISO_C:
1511                         IWL_DEBUG_RATE("LQ: MIMO2 switch to SISO\n");
1512
1513                         /* Set up new search table for SISO */
1514                         memcpy(search_tbl, tbl, sz);
1515
1516                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1517                                 search_tbl->ant_type = ANT_A;
1518                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1519                                 search_tbl->ant_type = ANT_B;
1520                         else
1521                                 search_tbl->ant_type = ANT_C;
1522
1523                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1524                                 break;
1525
1526                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1527                                                  search_tbl, index);
1528                         if (!ret)
1529                                 goto out;
1530
1531                         break;
1532
1533                 case IWL_MIMO2_SWITCH_GI:
1534                         if (!tbl->is_fat &&
1535                                 !(priv->current_ht_config.sgf &
1536                                                 HT_SHORT_GI_20MHZ))
1537                                 break;
1538                         if (tbl->is_fat &&
1539                                 !(priv->current_ht_config.sgf &
1540                                                 HT_SHORT_GI_40MHZ))
1541                                 break;
1542
1543                         IWL_DEBUG_RATE("LQ: MIMO toggle SGI/NGI\n");
1544
1545                         /* Set up new search table for MIMO */
1546                         memcpy(search_tbl, tbl, sz);
1547                         search_tbl->is_SGI = !tbl->is_SGI;
1548                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1549                         /*
1550                          * If active table already uses the fastest possible
1551                          * modulation (dual stream with short guard interval),
1552                          * and it's working well, there's no need to look
1553                          * for a better type of modulation!
1554                          */
1555                         if (tbl->is_SGI) {
1556                                 s32 tpt = lq_sta->last_tpt / 100;
1557                                 if (tpt >= search_tbl->expected_tpt[index])
1558                                         break;
1559                         }
1560                         search_tbl->current_rate = rate_n_flags_from_tbl(
1561                                                 search_tbl, index, is_green);
1562                         goto out;
1563
1564                 }
1565                 tbl->action++;
1566                 if (tbl->action > IWL_MIMO2_SWITCH_GI)
1567                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1568
1569                 if (tbl->action == start_action)
1570                         break;
1571         }
1572         search_tbl->lq_type = LQ_NONE;
1573         return 0;
1574  out:
1575         lq_sta->search_better_tbl = 1;
1576         tbl->action++;
1577         if (tbl->action > IWL_MIMO2_SWITCH_GI)
1578                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1579         return 0;
1580
1581 }
1582
1583 /*
1584  * Check whether we should continue using same modulation mode, or
1585  * begin search for a new mode, based on:
1586  * 1) # tx successes or failures while using this mode
1587  * 2) # times calling this function
1588  * 3) elapsed time in this mode (not used, for now)
1589  */
1590 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1591 {
1592         struct iwl_scale_tbl_info *tbl;
1593         int i;
1594         int active_tbl;
1595         int flush_interval_passed = 0;
1596         struct iwl_priv *priv;
1597
1598         priv = lq_sta->drv;
1599         active_tbl = lq_sta->active_tbl;
1600
1601         tbl = &(lq_sta->lq_info[active_tbl]);
1602
1603         /* If we've been disallowing search, see if we should now allow it */
1604         if (lq_sta->stay_in_tbl) {
1605
1606                 /* Elapsed time using current modulation mode */
1607                 if (lq_sta->flush_timer)
1608                         flush_interval_passed =
1609                             time_after(jiffies,
1610                                        (unsigned long)(lq_sta->flush_timer +
1611                                         IWL_RATE_SCALE_FLUSH_INTVL));
1612
1613                 /*
1614                  * Check if we should allow search for new modulation mode.
1615                  * If many frames have failed or succeeded, or we've used
1616                  * this same modulation for a long time, allow search, and
1617                  * reset history stats that keep track of whether we should
1618                  * allow a new search.  Also (below) reset all bitmaps and
1619                  * stats in active history.
1620                  */
1621                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1622                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1623                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1624                      && (flush_interval_passed))) {
1625                         IWL_DEBUG_RATE("LQ: stay is expired %d %d %d\n:",
1626                                      lq_sta->total_failed,
1627                                      lq_sta->total_success,
1628                                      flush_interval_passed);
1629
1630                         /* Allow search for new mode */
1631                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1632                         lq_sta->total_failed = 0;
1633                         lq_sta->total_success = 0;
1634                         lq_sta->flush_timer = 0;
1635
1636                 /*
1637                  * Else if we've used this modulation mode enough repetitions
1638                  * (regardless of elapsed time or success/failure), reset
1639                  * history bitmaps and rate-specific stats for all rates in
1640                  * active table.
1641                  */
1642                 } else {
1643                         lq_sta->table_count++;
1644                         if (lq_sta->table_count >=
1645                             lq_sta->table_count_limit) {
1646                                 lq_sta->table_count = 0;
1647
1648                                 IWL_DEBUG_RATE("LQ: stay in table clear win\n");
1649                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1650                                         rs_rate_scale_clear_window(
1651                                                 &(tbl->win[i]));
1652                         }
1653                 }
1654
1655                 /* If transitioning to allow "search", reset all history
1656                  * bitmaps and stats in active table (this will become the new
1657                  * "search" table). */
1658                 if (!lq_sta->stay_in_tbl) {
1659                         for (i = 0; i < IWL_RATE_COUNT; i++)
1660                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1661                 }
1662         }
1663 }
1664
1665 /*
1666  * Do rate scaling and search for new modulation mode.
1667  */
1668 static void rs_rate_scale_perform(struct iwl_priv *priv,
1669                                   struct ieee80211_hdr *hdr,
1670                                   struct ieee80211_sta *sta,
1671                                   struct iwl_lq_sta *lq_sta)
1672 {
1673         struct ieee80211_hw *hw = priv->hw;
1674         struct ieee80211_conf *conf = &hw->conf;
1675         int low = IWL_RATE_INVALID;
1676         int high = IWL_RATE_INVALID;
1677         int index;
1678         int i;
1679         struct iwl_rate_scale_data *window = NULL;
1680         int current_tpt = IWL_INVALID_VALUE;
1681         int low_tpt = IWL_INVALID_VALUE;
1682         int high_tpt = IWL_INVALID_VALUE;
1683         u32 fail_count;
1684         s8 scale_action = 0;
1685         __le16 fc;
1686         u16 rate_mask;
1687         u8 update_lq = 0;
1688         struct iwl_scale_tbl_info *tbl, *tbl1;
1689         u16 rate_scale_index_msk = 0;
1690         u32 rate;
1691         u8 is_green = 0;
1692         u8 active_tbl = 0;
1693         u8 done_search = 0;
1694         u16 high_low;
1695         s32 sr;
1696         u8 tid = MAX_TID_COUNT;
1697
1698         IWL_DEBUG_RATE("rate scale calculate new rate for skb\n");
1699
1700         fc = hdr->frame_control;
1701         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1)) {
1702                 /* Send management frames and broadcast/multicast data using
1703                  * lowest rate. */
1704                 /* TODO: this could probably be improved.. */
1705                 return;
1706         }
1707
1708         if (!sta || !lq_sta)
1709                 return;
1710
1711         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1712
1713         tid = rs_tl_add_packet(lq_sta, hdr);
1714
1715         /*
1716          * Select rate-scale / modulation-mode table to work with in
1717          * the rest of this function:  "search" if searching for better
1718          * modulation mode, or "active" if doing rate scaling within a mode.
1719          */
1720         if (!lq_sta->search_better_tbl)
1721                 active_tbl = lq_sta->active_tbl;
1722         else
1723                 active_tbl = 1 - lq_sta->active_tbl;
1724
1725         tbl = &(lq_sta->lq_info[active_tbl]);
1726         is_green = lq_sta->is_green;
1727
1728         /* current tx rate */
1729         index = lq_sta->last_txrate_idx;
1730
1731         IWL_DEBUG_RATE("Rate scale index %d for type %d\n", index,
1732                        tbl->lq_type);
1733
1734         /* rates available for this association, and for modulation mode */
1735         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1736
1737         IWL_DEBUG_RATE("mask 0x%04X \n", rate_mask);
1738
1739         /* mask with station rate restriction */
1740         if (is_legacy(tbl->lq_type)) {
1741                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
1742                         /* supp_rates has no CCK bits in A mode */
1743                         rate_scale_index_msk = (u16) (rate_mask &
1744                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1745                 else
1746                         rate_scale_index_msk = (u16) (rate_mask &
1747                                                       lq_sta->supp_rates);
1748
1749         } else
1750                 rate_scale_index_msk = rate_mask;
1751
1752         if (!rate_scale_index_msk)
1753                 rate_scale_index_msk = rate_mask;
1754
1755         if (!((1 << index) & rate_scale_index_msk)) {
1756                 IWL_ERROR("Current Rate is not valid\n");
1757                 return;
1758         }
1759
1760         /* Get expected throughput table and history window for current rate */
1761         if (!tbl->expected_tpt) {
1762                 IWL_ERROR("tbl->expected_tpt is NULL\n");
1763                 return;
1764         }
1765
1766         window = &(tbl->win[index]);
1767
1768         /*
1769          * If there is not enough history to calculate actual average
1770          * throughput, keep analyzing results of more tx frames, without
1771          * changing rate or mode (bypass most of the rest of this function).
1772          * Set up new rate table in uCode only if old rate is not supported
1773          * in current association (use new rate found above).
1774          */
1775         fail_count = window->counter - window->success_counter;
1776         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1777                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
1778                 IWL_DEBUG_RATE("LQ: still below TH. succ=%d total=%d "
1779                                "for index %d\n",
1780                                window->success_counter, window->counter, index);
1781
1782                 /* Can't calculate this yet; not enough history */
1783                 window->average_tpt = IWL_INVALID_VALUE;
1784
1785                 /* Should we stay with this modulation mode,
1786                  * or search for a new one? */
1787                 rs_stay_in_table(lq_sta);
1788
1789                 goto out;
1790         }
1791
1792         /* Else we have enough samples; calculate estimate of
1793          * actual average throughput */
1794
1795         BUG_ON(window->average_tpt != ((window->success_ratio *
1796                         tbl->expected_tpt[index] + 64) / 128));
1797
1798         /* If we are searching for better modulation mode, check success. */
1799         if (lq_sta->search_better_tbl) {
1800
1801                 /* If good success, continue using the "search" mode;
1802                  * no need to send new link quality command, since we're
1803                  * continuing to use the setup that we've been trying. */
1804                 if (window->average_tpt > lq_sta->last_tpt) {
1805
1806                         IWL_DEBUG_RATE("LQ: SWITCHING TO NEW TABLE "
1807                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1808                                         window->success_ratio,
1809                                         window->average_tpt,
1810                                         lq_sta->last_tpt);
1811
1812                         if (!is_legacy(tbl->lq_type))
1813                                 lq_sta->enable_counter = 1;
1814
1815                         /* Swap tables; "search" becomes "active" */
1816                         lq_sta->active_tbl = active_tbl;
1817                         current_tpt = window->average_tpt;
1818
1819                 /* Else poor success; go back to mode in "active" table */
1820                 } else {
1821
1822                         IWL_DEBUG_RATE("LQ: GOING BACK TO THE OLD TABLE "
1823                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1824                                         window->success_ratio,
1825                                         window->average_tpt,
1826                                         lq_sta->last_tpt);
1827
1828                         /* Nullify "search" table */
1829                         tbl->lq_type = LQ_NONE;
1830
1831                         /* Revert to "active" table */
1832                         active_tbl = lq_sta->active_tbl;
1833                         tbl = &(lq_sta->lq_info[active_tbl]);
1834
1835                         /* Revert to "active" rate and throughput info */
1836                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1837                         current_tpt = lq_sta->last_tpt;
1838
1839                         /* Need to set up a new rate table in uCode */
1840                         update_lq = 1;
1841                 }
1842
1843                 /* Either way, we've made a decision; modulation mode
1844                  * search is done, allow rate adjustment next time. */
1845                 lq_sta->search_better_tbl = 0;
1846                 done_search = 1;        /* Don't switch modes below! */
1847                 goto lq_update;
1848         }
1849
1850         /* (Else) not in search of better modulation mode, try for better
1851          * starting rate, while staying in this mode. */
1852         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
1853                                         tbl->lq_type);
1854         low = high_low & 0xff;
1855         high = (high_low >> 8) & 0xff;
1856
1857         sr = window->success_ratio;
1858
1859         /* Collect measured throughputs for current and adjacent rates */
1860         current_tpt = window->average_tpt;
1861         if (low != IWL_RATE_INVALID)
1862                 low_tpt = tbl->win[low].average_tpt;
1863         if (high != IWL_RATE_INVALID)
1864                 high_tpt = tbl->win[high].average_tpt;
1865
1866         scale_action = 0;
1867
1868         /* Too many failures, decrease rate */
1869         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
1870                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
1871                 scale_action = -1;
1872
1873         /* No throughput measured yet for adjacent rates; try increase. */
1874         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1875                    (high_tpt == IWL_INVALID_VALUE)) {
1876
1877                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
1878                         scale_action = 1;
1879                 else if (low != IWL_RATE_INVALID)
1880                         scale_action = -1;
1881         }
1882
1883         /* Both adjacent throughputs are measured, but neither one has better
1884          * throughput; we're using the best rate, don't change it! */
1885         else if ((low_tpt != IWL_INVALID_VALUE) &&
1886                  (high_tpt != IWL_INVALID_VALUE) &&
1887                  (low_tpt < current_tpt) &&
1888                  (high_tpt < current_tpt))
1889                 scale_action = 0;
1890
1891         /* At least one adjacent rate's throughput is measured,
1892          * and may have better performance. */
1893         else {
1894                 /* Higher adjacent rate's throughput is measured */
1895                 if (high_tpt != IWL_INVALID_VALUE) {
1896                         /* Higher rate has better throughput */
1897                         if (high_tpt > current_tpt &&
1898                                         sr >= IWL_RATE_INCREASE_TH) {
1899                                 scale_action = 1;
1900                         } else {
1901                                 IWL_DEBUG_RATE
1902                                     ("decrease rate because of high tpt\n");
1903                                 scale_action = -1;
1904                         }
1905
1906                 /* Lower adjacent rate's throughput is measured */
1907                 } else if (low_tpt != IWL_INVALID_VALUE) {
1908                         /* Lower rate has better throughput */
1909                         if (low_tpt > current_tpt) {
1910                                 IWL_DEBUG_RATE
1911                                     ("decrease rate because of low tpt\n");
1912                                 scale_action = -1;
1913                         } else if (sr >= IWL_RATE_INCREASE_TH) {
1914                                 scale_action = 1;
1915                         }
1916                 }
1917         }
1918
1919         /* Sanity check; asked for decrease, but success rate or throughput
1920          * has been good at old rate.  Don't change it. */
1921         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
1922                     ((sr > IWL_RATE_HIGH_TH) ||
1923                      (current_tpt > (100 * tbl->expected_tpt[low]))))
1924                 scale_action = 0;
1925
1926         switch (scale_action) {
1927         case -1:
1928                 /* Decrease starting rate, update uCode's rate table */
1929                 if (low != IWL_RATE_INVALID) {
1930                         update_lq = 1;
1931                         index = low;
1932                 }
1933                 break;
1934         case 1:
1935                 /* Increase starting rate, update uCode's rate table */
1936                 if (high != IWL_RATE_INVALID) {
1937                         update_lq = 1;
1938                         index = high;
1939                 }
1940
1941                 break;
1942         case 0:
1943                 /* No change */
1944         default:
1945                 break;
1946         }
1947
1948         IWL_DEBUG_RATE("choose rate scale index %d action %d low %d "
1949                     "high %d type %d\n",
1950                      index, scale_action, low, high, tbl->lq_type);
1951
1952 lq_update:
1953         /* Replace uCode's rate table for the destination station. */
1954         if (update_lq) {
1955                 rate = rate_n_flags_from_tbl(tbl, index, is_green);
1956                 rs_fill_link_cmd(priv, lq_sta, rate);
1957                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1958         }
1959
1960         /* Should we stay with this modulation mode, or search for a new one? */
1961         rs_stay_in_table(lq_sta);
1962
1963         /*
1964          * Search for new modulation mode if we're:
1965          * 1)  Not changing rates right now
1966          * 2)  Not just finishing up a search
1967          * 3)  Allowing a new search
1968          */
1969         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
1970                 /* Save current throughput to compare with "search" throughput*/
1971                 lq_sta->last_tpt = current_tpt;
1972
1973                 /* Select a new "search" modulation mode to try.
1974                  * If one is found, set up the new "search" table. */
1975                 if (is_legacy(tbl->lq_type))
1976                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
1977                 else if (is_siso(tbl->lq_type))
1978                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
1979                 else
1980                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
1981
1982                 /* If new "search" mode was selected, set up in uCode table */
1983                 if (lq_sta->search_better_tbl) {
1984                         /* Access the "search" table, clear its history. */
1985                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1986                         for (i = 0; i < IWL_RATE_COUNT; i++)
1987                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1988
1989                         /* Use new "search" start rate */
1990                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1991
1992                         IWL_DEBUG_RATE("Switch current  mcs: %X index: %d\n",
1993                                      tbl->current_rate, index);
1994                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
1995                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1996                 }
1997
1998                 /* If the "active" (non-search) mode was legacy,
1999                  * and we've tried switching antennas,
2000                  * but we haven't been able to try HT modes (not available),
2001                  * stay with best antenna legacy modulation for a while
2002                  * before next round of mode comparisons. */
2003                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2004                 if (is_legacy(tbl1->lq_type) &&
2005                    (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE)) &&
2006                     (lq_sta->action_counter >= 1)) {
2007                         lq_sta->action_counter = 0;
2008                         IWL_DEBUG_RATE("LQ: STAY in legacy table\n");
2009                         rs_set_stay_in_table(priv, 1, lq_sta);
2010                 }
2011
2012                 /* If we're in an HT mode, and all 3 mode switch actions
2013                  * have been tried and compared, stay in this best modulation
2014                  * mode for a while before next round of mode comparisons. */
2015                 if (lq_sta->enable_counter &&
2016                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
2017                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2018                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2019                             (tid != MAX_TID_COUNT)) {
2020                                 IWL_DEBUG_RATE("try to aggregate tid %d\n", tid);
2021                                 rs_tl_turn_on_agg(priv, tid, lq_sta, sta);
2022                         }
2023                         lq_sta->action_counter = 0;
2024                         rs_set_stay_in_table(priv, 0, lq_sta);
2025                 }
2026
2027         /*
2028          * Else, don't search for a new modulation mode.
2029          * Put new timestamp in stay-in-modulation-mode flush timer if:
2030          * 1)  Not changing rates right now
2031          * 2)  Not just finishing up a search
2032          * 3)  flush timer is empty
2033          */
2034         } else {
2035                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
2036                         lq_sta->flush_timer = jiffies;
2037         }
2038
2039 out:
2040         tbl->current_rate = rate_n_flags_from_tbl(tbl, index, is_green);
2041         i = index;
2042         lq_sta->last_txrate_idx = i;
2043
2044         return;
2045 }
2046
2047
2048 static void rs_initialize_lq(struct iwl_priv *priv,
2049                              struct ieee80211_conf *conf,
2050                              struct ieee80211_sta *sta,
2051                              struct iwl_lq_sta *lq_sta)
2052 {
2053         struct iwl_scale_tbl_info *tbl;
2054         int rate_idx;
2055         int i;
2056         u32 rate;
2057         u8 use_green = rs_use_green(priv, conf);
2058         u8 active_tbl = 0;
2059         u8 valid_tx_ant;
2060
2061         if (!sta || !lq_sta)
2062                 goto out;
2063
2064         i = lq_sta->last_txrate_idx;
2065
2066         if ((lq_sta->lq.sta_id == 0xff) &&
2067             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2068                 goto out;
2069
2070         valid_tx_ant = priv->hw_params.valid_tx_ant;
2071
2072         if (!lq_sta->search_better_tbl)
2073                 active_tbl = lq_sta->active_tbl;
2074         else
2075                 active_tbl = 1 - lq_sta->active_tbl;
2076
2077         tbl = &(lq_sta->lq_info[active_tbl]);
2078
2079         if ((i < 0) || (i >= IWL_RATE_COUNT))
2080                 i = 0;
2081
2082         /* FIXME:RS: This is also wrong in 4965 */
2083         rate = iwl_rates[i].plcp;
2084         rate |= RATE_MCS_ANT_B_MSK;
2085         rate &= ~RATE_MCS_ANT_A_MSK;
2086
2087         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2088                 rate |= RATE_MCS_CCK_MSK;
2089
2090         tbl->ant_type = ANT_B;
2091         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2092         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2093             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2094
2095         rate = rate_n_flags_from_tbl(tbl, rate_idx, use_green);
2096         tbl->current_rate = rate;
2097         rs_set_expected_tpt_table(lq_sta, tbl);
2098         rs_fill_link_cmd(NULL, lq_sta, rate);
2099         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2100  out:
2101         return;
2102 }
2103
2104 static void rs_get_rate(void *priv_r, struct ieee80211_supported_band *sband,
2105                         struct ieee80211_sta *sta, void *priv_sta,
2106                         struct sk_buff *skb, struct rate_selection *sel)
2107 {
2108
2109         int i;
2110         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2111         struct ieee80211_conf *conf = &priv->hw->conf;
2112         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2113         __le16 fc;
2114         struct iwl_lq_sta *lq_sta;
2115
2116         IWL_DEBUG_RATE_LIMIT("rate scale calculate new rate for skb\n");
2117
2118         /* Send management frames and broadcast/multicast data using lowest
2119          * rate. */
2120         fc = hdr->frame_control;
2121         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1) ||
2122             !sta || !priv_sta) {
2123                 sel->rate_idx = rate_lowest_index(sband, sta);
2124                 return;
2125         }
2126
2127         lq_sta = (struct iwl_lq_sta *)priv_sta;
2128         i = lq_sta->last_txrate_idx;
2129
2130         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2131             !lq_sta->ibss_sta_added) {
2132                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2133
2134                 if (sta_id == IWL_INVALID_STATION) {
2135                         IWL_DEBUG_RATE("LQ: ADD station %pM\n",
2136                                        hdr->addr1);
2137                         sta_id = iwl_add_station_flags(priv, hdr->addr1,
2138                                                         0, CMD_ASYNC, NULL);
2139                 }
2140                 if ((sta_id != IWL_INVALID_STATION)) {
2141                         lq_sta->lq.sta_id = sta_id;
2142                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2143                         lq_sta->ibss_sta_added = 1;
2144                         rs_initialize_lq(priv, conf, sta, lq_sta);
2145                 }
2146         }
2147
2148         if ((i < 0) || (i > IWL_RATE_COUNT)) {
2149                 sel->rate_idx = rate_lowest_index(sband, sta);
2150                 return;
2151         }
2152
2153         if (sband->band == IEEE80211_BAND_5GHZ)
2154                 i -= IWL_FIRST_OFDM_RATE;
2155         sel->rate_idx = i;
2156 }
2157
2158 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2159                           gfp_t gfp)
2160 {
2161         struct iwl_lq_sta *lq_sta;
2162         struct iwl_priv *priv;
2163         int i, j;
2164
2165         priv = (struct iwl_priv *)priv_rate;
2166         IWL_DEBUG_RATE("create station rate scale window\n");
2167
2168         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2169
2170         if (lq_sta == NULL)
2171                 return NULL;
2172         lq_sta->lq.sta_id = 0xff;
2173
2174
2175         for (j = 0; j < LQ_SIZE; j++)
2176                 for (i = 0; i < IWL_RATE_COUNT; i++)
2177                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2178
2179         return lq_sta;
2180 }
2181
2182 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2183                          struct ieee80211_sta *sta, void *priv_sta)
2184 {
2185         int i, j;
2186         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2187         struct ieee80211_conf *conf = &priv->hw->conf;
2188         struct iwl_lq_sta *lq_sta = priv_sta;
2189
2190         lq_sta->flush_timer = 0;
2191         lq_sta->supp_rates = sta->supp_rates[sband->band];
2192         for (j = 0; j < LQ_SIZE; j++)
2193                 for (i = 0; i < IWL_RATE_COUNT; i++)
2194                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2195
2196         IWL_DEBUG_RATE("LQ: *** rate scale station global init ***\n");
2197         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2198          * the lowest or the highest rate.. Could consider using RSSI from
2199          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2200          * after assoc.. */
2201
2202         lq_sta->ibss_sta_added = 0;
2203         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2204                 u8 sta_id = iwl_find_station(priv, sta->addr);
2205
2206                 /* for IBSS the call are from tasklet */
2207                 IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2208
2209                 if (sta_id == IWL_INVALID_STATION) {
2210                         IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2211                         sta_id = iwl_add_station_flags(priv, sta->addr,
2212                                                         0, CMD_ASYNC, NULL);
2213                 }
2214                 if ((sta_id != IWL_INVALID_STATION)) {
2215                         lq_sta->lq.sta_id = sta_id;
2216                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2217                 }
2218                 /* FIXME: this is w/a remove it later */
2219                 priv->assoc_station_added = 1;
2220         }
2221
2222         /* Find highest tx rate supported by hardware and destination station */
2223         lq_sta->last_txrate_idx = 3;
2224         for (i = 0; i < sband->n_bitrates; i++)
2225                 if (sta->supp_rates[sband->band] & BIT(i))
2226                         lq_sta->last_txrate_idx = i;
2227
2228         /* For MODE_IEEE80211A, skip over cck rates in global rate table */
2229         if (sband->band == IEEE80211_BAND_5GHZ)
2230                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2231
2232         lq_sta->is_dup = 0;
2233         lq_sta->is_green = rs_use_green(priv, conf);
2234         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2235         lq_sta->active_rate_basic = priv->active_rate_basic;
2236         lq_sta->band = priv->band;
2237         /*
2238          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2239          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2240          */
2241         lq_sta->active_siso_rate = conf->ht_cap.mcs.rx_mask[0] << 1;
2242         lq_sta->active_siso_rate |= conf->ht_cap.mcs.rx_mask[0] & 0x1;
2243         lq_sta->active_siso_rate &= ~((u16)0x2);
2244         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2245
2246         /* Same here */
2247         lq_sta->active_mimo2_rate = conf->ht_cap.mcs.rx_mask[1] << 1;
2248         lq_sta->active_mimo2_rate |= conf->ht_cap.mcs.rx_mask[1] & 0x1;
2249         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2250         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2251
2252         lq_sta->active_mimo3_rate = conf->ht_cap.mcs.rx_mask[2] << 1;
2253         lq_sta->active_mimo3_rate |= conf->ht_cap.mcs.rx_mask[2] & 0x1;
2254         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2255         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2256
2257         IWL_DEBUG_RATE("SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2258                      lq_sta->active_siso_rate,
2259                      lq_sta->active_mimo2_rate,
2260                      lq_sta->active_mimo3_rate);
2261
2262         /* These values will be overriden later */
2263         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2264         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2265
2266         /* as default allow aggregation for all tids */
2267         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2268         lq_sta->drv = priv;
2269
2270         rs_initialize_lq(priv, conf, sta, lq_sta);
2271 }
2272
2273 static void rs_fill_link_cmd(const struct iwl_priv *priv,
2274                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2275 {
2276         struct iwl_scale_tbl_info tbl_type;
2277         int index = 0;
2278         int rate_idx;
2279         int repeat_rate = 0;
2280         u8 ant_toggle_cnt = 0;
2281         u8 use_ht_possible = 1;
2282         u8 valid_tx_ant = 0;
2283         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2284
2285         /* Override starting rate (index 0) if needed for debug purposes */
2286         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2287
2288         /* Interpret new_rate (rate_n_flags) */
2289         memset(&tbl_type, 0, sizeof(tbl_type));
2290         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2291                                   &tbl_type, &rate_idx);
2292
2293         /* How many times should we repeat the initial rate? */
2294         if (is_legacy(tbl_type.lq_type)) {
2295                 ant_toggle_cnt = 1;
2296                 repeat_rate = IWL_NUMBER_TRY;
2297         } else {
2298                 repeat_rate = IWL_HT_NUMBER_TRY;
2299         }
2300
2301         lq_cmd->general_params.mimo_delimiter =
2302                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2303
2304         /* Fill 1st table entry (index 0) */
2305         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2306
2307         if (num_of_ant(tbl_type.ant_type) == 1) {
2308                 lq_cmd->general_params.single_stream_ant_msk =
2309                                                 tbl_type.ant_type;
2310         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2311                 lq_cmd->general_params.dual_stream_ant_msk =
2312                                                 tbl_type.ant_type;
2313         } /* otherwise we don't modify the existing value */
2314
2315         index++;
2316         repeat_rate--;
2317
2318         if (priv)
2319                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2320
2321         /* Fill rest of rate table */
2322         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2323                 /* Repeat initial/next rate.
2324                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2325                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2326                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2327                         if (is_legacy(tbl_type.lq_type)) {
2328                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2329                                         ant_toggle_cnt++;
2330                                 else if (priv &&
2331                                          rs_toggle_antenna(valid_tx_ant,
2332                                                         &new_rate, &tbl_type))
2333                                         ant_toggle_cnt = 1;
2334 }
2335
2336                         /* Override next rate if needed for debug purposes */
2337                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2338
2339                         /* Fill next table entry */
2340                         lq_cmd->rs_table[index].rate_n_flags =
2341                                         cpu_to_le32(new_rate);
2342                         repeat_rate--;
2343                         index++;
2344                 }
2345
2346                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2347                                                 &rate_idx);
2348
2349                 /* Indicate to uCode which entries might be MIMO.
2350                  * If initial rate was MIMO, this will finally end up
2351                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2352                 if (is_mimo(tbl_type.lq_type))
2353                         lq_cmd->general_params.mimo_delimiter = index;
2354
2355                 /* Get next rate */
2356                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2357                                              use_ht_possible);
2358
2359                 /* How many times should we repeat the next rate? */
2360                 if (is_legacy(tbl_type.lq_type)) {
2361                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2362                                 ant_toggle_cnt++;
2363                         else if (priv &&
2364                                  rs_toggle_antenna(valid_tx_ant,
2365                                                    &new_rate, &tbl_type))
2366                                 ant_toggle_cnt = 1;
2367
2368                         repeat_rate = IWL_NUMBER_TRY;
2369                 } else {
2370                         repeat_rate = IWL_HT_NUMBER_TRY;
2371                 }
2372
2373                 /* Don't allow HT rates after next pass.
2374                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2375                 use_ht_possible = 0;
2376
2377                 /* Override next rate if needed for debug purposes */
2378                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2379
2380                 /* Fill next table entry */
2381                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2382
2383                 index++;
2384                 repeat_rate--;
2385         }
2386
2387         lq_cmd->agg_params.agg_frame_cnt_limit = 64;
2388         lq_cmd->agg_params.agg_dis_start_th = 3;
2389         lq_cmd->agg_params.agg_time_limit = cpu_to_le16(4000);
2390 }
2391
2392 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2393 {
2394         return hw->priv;
2395 }
2396 /* rate scale requires free function to be implemented */
2397 static void rs_free(void *priv_rate)
2398 {
2399         return;
2400 }
2401
2402 static void rs_clear(void *priv_rate)
2403 {
2404 #ifdef CONFIG_IWLWIFI_DEBUG
2405         struct iwl_priv *priv = (struct iwl_priv *) priv_rate;
2406
2407         IWL_DEBUG_RATE("enter\n");
2408
2409         /* TODO - add rate scale state reset */
2410
2411         IWL_DEBUG_RATE("leave\n");
2412 #endif /* CONFIG_IWLWIFI_DEBUG */
2413 }
2414
2415 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2416                         void *priv_sta)
2417 {
2418         struct iwl_lq_sta *lq_sta = priv_sta;
2419         struct iwl_priv *priv __maybe_unused = priv_r;
2420
2421         IWL_DEBUG_RATE("enter\n");
2422         kfree(lq_sta);
2423         IWL_DEBUG_RATE("leave\n");
2424 }
2425
2426
2427 #ifdef CONFIG_MAC80211_DEBUGFS
2428 static int open_file_generic(struct inode *inode, struct file *file)
2429 {
2430         file->private_data = inode->i_private;
2431         return 0;
2432 }
2433 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2434                              u32 *rate_n_flags, int index)
2435 {
2436         struct iwl_priv *priv;
2437
2438         priv = lq_sta->drv;
2439         if (lq_sta->dbg_fixed_rate) {
2440                 if (index < 12) {
2441                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2442                 } else {
2443                         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2444                                 *rate_n_flags = 0x800D;
2445                         else
2446                                 *rate_n_flags = 0x820A;
2447                 }
2448                 IWL_DEBUG_RATE("Fixed rate ON\n");
2449         } else {
2450                 IWL_DEBUG_RATE("Fixed rate OFF\n");
2451         }
2452 }
2453
2454 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2455                         const char __user *user_buf, size_t count, loff_t *ppos)
2456 {
2457         struct iwl_lq_sta *lq_sta = file->private_data;
2458         struct iwl_priv *priv;
2459         char buf[64];
2460         int buf_size;
2461         u32 parsed_rate;
2462
2463         priv = lq_sta->drv;
2464         memset(buf, 0, sizeof(buf));
2465         buf_size = min(count, sizeof(buf) -  1);
2466         if (copy_from_user(buf, user_buf, buf_size))
2467                 return -EFAULT;
2468
2469         if (sscanf(buf, "%x", &parsed_rate) == 1)
2470                 lq_sta->dbg_fixed_rate = parsed_rate;
2471         else
2472                 lq_sta->dbg_fixed_rate = 0;
2473
2474         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2475         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2476         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2477         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2478
2479         IWL_DEBUG_RATE("sta_id %d rate 0x%X\n",
2480                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2481
2482         if (lq_sta->dbg_fixed_rate) {
2483                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2484                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2485         }
2486
2487         return count;
2488 }
2489
2490 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2491                         char __user *user_buf, size_t count, loff_t *ppos)
2492 {
2493         char buff[1024];
2494         int desc = 0;
2495         int i = 0;
2496
2497         struct iwl_lq_sta *lq_sta = file->private_data;
2498
2499         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2500         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2501                         lq_sta->total_failed, lq_sta->total_success,
2502                         lq_sta->active_legacy_rate);
2503         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2504                         lq_sta->dbg_fixed_rate);
2505         desc += sprintf(buff+desc, "general:"
2506                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2507                 lq_sta->lq.general_params.flags,
2508                 lq_sta->lq.general_params.mimo_delimiter,
2509                 lq_sta->lq.general_params.single_stream_ant_msk,
2510                 lq_sta->lq.general_params.dual_stream_ant_msk);
2511
2512         desc += sprintf(buff+desc, "agg:"
2513                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2514                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2515                         lq_sta->lq.agg_params.agg_dis_start_th,
2516                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2517
2518         desc += sprintf(buff+desc,
2519                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2520                         lq_sta->lq.general_params.start_rate_index[0],
2521                         lq_sta->lq.general_params.start_rate_index[1],
2522                         lq_sta->lq.general_params.start_rate_index[2],
2523                         lq_sta->lq.general_params.start_rate_index[3]);
2524
2525
2526         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2527                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2528                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2529
2530         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2531 }
2532
2533 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2534         .write = rs_sta_dbgfs_scale_table_write,
2535         .read = rs_sta_dbgfs_scale_table_read,
2536         .open = open_file_generic,
2537 };
2538 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2539                         char __user *user_buf, size_t count, loff_t *ppos)
2540 {
2541         char buff[1024];
2542         int desc = 0;
2543         int i, j;
2544
2545         struct iwl_lq_sta *lq_sta = file->private_data;
2546         for (i = 0; i < LQ_SIZE; i++) {
2547                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2548                                 "rate=0x%X\n",
2549                                 lq_sta->active_tbl == i?"*":"x",
2550                                 lq_sta->lq_info[i].lq_type,
2551                                 lq_sta->lq_info[i].is_SGI,
2552                                 lq_sta->lq_info[i].is_fat,
2553                                 lq_sta->lq_info[i].is_dup,
2554                                 lq_sta->lq_info[i].current_rate);
2555                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2556                         desc += sprintf(buff+desc,
2557                                 "counter=%d success=%d %%=%d\n",
2558                                 lq_sta->lq_info[i].win[j].counter,
2559                                 lq_sta->lq_info[i].win[j].success_counter,
2560                                 lq_sta->lq_info[i].win[j].success_ratio);
2561                 }
2562         }
2563         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2564 }
2565
2566 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2567         .read = rs_sta_dbgfs_stats_table_read,
2568         .open = open_file_generic,
2569 };
2570
2571 static void rs_add_debugfs(void *priv, void *priv_sta,
2572                                         struct dentry *dir)
2573 {
2574         struct iwl_lq_sta *lq_sta = priv_sta;
2575         lq_sta->rs_sta_dbgfs_scale_table_file =
2576                 debugfs_create_file("rate_scale_table", 0600, dir,
2577                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2578         lq_sta->rs_sta_dbgfs_stats_table_file =
2579                 debugfs_create_file("rate_stats_table", 0600, dir,
2580                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2581         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2582                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2583                 &lq_sta->tx_agg_tid_en);
2584
2585 }
2586
2587 static void rs_remove_debugfs(void *priv, void *priv_sta)
2588 {
2589         struct iwl_lq_sta *lq_sta = priv_sta;
2590         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2591         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2592         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2593 }
2594 #endif
2595
2596 static struct rate_control_ops rs_ops = {
2597         .module = NULL,
2598         .name = RS_NAME,
2599         .tx_status = rs_tx_status,
2600         .get_rate = rs_get_rate,
2601         .rate_init = rs_rate_init,
2602         .clear = rs_clear,
2603         .alloc = rs_alloc,
2604         .free = rs_free,
2605         .alloc_sta = rs_alloc_sta,
2606         .free_sta = rs_free_sta,
2607 #ifdef CONFIG_MAC80211_DEBUGFS
2608         .add_sta_debugfs = rs_add_debugfs,
2609         .remove_sta_debugfs = rs_remove_debugfs,
2610 #endif
2611 };
2612
2613 int iwlagn_rate_control_register(void)
2614 {
2615         return ieee80211_rate_control_register(&rs_ops);
2616 }
2617
2618 void iwlagn_rate_control_unregister(void)
2619 {
2620         ieee80211_rate_control_unregister(&rs_ops);
2621 }
2622