Merge branch 'fix/asoc' into for-linus
[linux-2.6] / drivers / net / wireless / iwlwifi / iwl-agn-rs.c
1 /******************************************************************************
2  *
3  * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
17  *
18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  * Contact Information:
22  *  Intel Linux Wireless <ilw@linux.intel.com>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  *****************************************************************************/
26 #include <linux/kernel.h>
27 #include <linux/init.h>
28 #include <linux/skbuff.h>
29 #include <linux/wireless.h>
30 #include <net/mac80211.h>
31
32 #include <linux/netdevice.h>
33 #include <linux/etherdevice.h>
34 #include <linux/delay.h>
35
36 #include <linux/workqueue.h>
37
38 #include "iwl-dev.h"
39 #include "iwl-sta.h"
40 #include "iwl-core.h"
41
42 #define RS_NAME "iwl-agn-rs"
43
44 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
45 #define IWL_NUMBER_TRY      1
46 #define IWL_HT_NUMBER_TRY   3
47
48 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
49 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
50 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
51
52 /* max time to accum history 2 seconds */
53 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
54
55 static u8 rs_ht_to_legacy[] = {
56         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
57         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
58         IWL_RATE_6M_INDEX,
59         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
60         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
61         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
62         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
63 };
64
65 static const u8 ant_toggle_lookup[] = {
66         /*ANT_NONE -> */ ANT_NONE,
67         /*ANT_A    -> */ ANT_B,
68         /*ANT_B    -> */ ANT_C,
69         /*ANT_AB   -> */ ANT_BC,
70         /*ANT_C    -> */ ANT_A,
71         /*ANT_AC   -> */ ANT_AB,
72         /*ANT_BC   -> */ ANT_AC,
73         /*ANT_ABC  -> */ ANT_ABC,
74 };
75
76 /**
77  * struct iwl_rate_scale_data -- tx success history for one rate
78  */
79 struct iwl_rate_scale_data {
80         u64 data;               /* bitmap of successful frames */
81         s32 success_counter;    /* number of frames successful */
82         s32 success_ratio;      /* per-cent * 128  */
83         s32 counter;            /* number of frames attempted */
84         s32 average_tpt;        /* success ratio * expected throughput */
85         unsigned long stamp;
86 };
87
88 /**
89  * struct iwl_scale_tbl_info -- tx params and success history for all rates
90  *
91  * There are two of these in struct iwl_lq_sta,
92  * one for "active", and one for "search".
93  */
94 struct iwl_scale_tbl_info {
95         enum iwl_table_type lq_type;
96         u8 ant_type;
97         u8 is_SGI;      /* 1 = short guard interval */
98         u8 is_fat;      /* 1 = 40 MHz channel width */
99         u8 is_dup;      /* 1 = duplicated data streams */
100         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
101         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
102         u32 current_rate;  /* rate_n_flags, uCode API format */
103         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
104 };
105
106 struct iwl_traffic_load {
107         unsigned long time_stamp;       /* age of the oldest statistics */
108         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
109                                                  * slice */
110         u32 total;                      /* total num of packets during the
111                                          * last TID_MAX_TIME_DIFF */
112         u8 queue_count;                 /* number of queues that has
113                                          * been used since the last cleanup */
114         u8 head;                        /* start of the circular buffer */
115 };
116
117 /**
118  * struct iwl_lq_sta -- driver's rate scaling private structure
119  *
120  * Pointer to this gets passed back and forth between driver and mac80211.
121  */
122 struct iwl_lq_sta {
123         u8 active_tbl;          /* index of active table, range 0-1 */
124         u8 enable_counter;      /* indicates HT mode */
125         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
126         u8 search_better_tbl;   /* 1: currently trying alternate mode */
127         s32 last_tpt;
128
129         /* The following determine when to search for a new mode */
130         u32 table_count_limit;
131         u32 max_failure_limit;  /* # failed frames before new search */
132         u32 max_success_limit;  /* # successful frames before new search */
133         u32 table_count;
134         u32 total_failed;       /* total failed frames, any/all rates */
135         u32 total_success;      /* total successful frames, any/all rates */
136         u32 flush_timer;        /* time staying in mode before new search */
137
138         u8 action_counter;      /* # mode-switch actions tried */
139         u8 is_green;
140         u8 is_dup;
141         enum ieee80211_band band;
142         u8 ibss_sta_added;
143
144         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
145         u32 supp_rates;
146         u16 active_legacy_rate;
147         u16 active_siso_rate;
148         u16 active_mimo2_rate;
149         u16 active_mimo3_rate;
150         u16 active_rate_basic;
151
152         struct iwl_link_quality_cmd lq;
153         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
154         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
155         u8 tx_agg_tid_en;
156 #ifdef CONFIG_MAC80211_DEBUGFS
157         struct dentry *rs_sta_dbgfs_scale_table_file;
158         struct dentry *rs_sta_dbgfs_stats_table_file;
159         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
160         u32 dbg_fixed_rate;
161 #endif
162         struct iwl_priv *drv;
163
164         /* used to be in sta_info */
165         int last_txrate_idx;
166 };
167
168 static void rs_rate_scale_perform(struct iwl_priv *priv,
169                                    struct ieee80211_hdr *hdr,
170                                    struct ieee80211_sta *sta,
171                                    struct iwl_lq_sta *lq_sta);
172 static void rs_fill_link_cmd(const struct iwl_priv *priv,
173                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
174
175
176 #ifdef CONFIG_MAC80211_DEBUGFS
177 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
178                              u32 *rate_n_flags, int index);
179 #else
180 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
181                              u32 *rate_n_flags, int index)
182 {}
183 #endif
184
185 /*
186  * Expected throughput metrics for following rates:
187  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
188  * "G" is the only table that supports CCK (the first 4 rates).
189  */
190 /*FIXME:RS:need to separate tables for MIMO2/MIMO3*/
191 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
192         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
193 };
194
195 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
196         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
197 };
198
199 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
200         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
201 };
202
203 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
204         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
205 };
206
207 static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
208         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
209 };
210
211 static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
212         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
213 };
214
215 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
216         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
217 };
218
219 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
220         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
221 };
222
223 static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
224         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
225 };
226
227 static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
228         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
229 };
230
231 static inline u8 rs_extract_rate(u32 rate_n_flags)
232 {
233         return (u8)(rate_n_flags & 0xFF);
234 }
235
236 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
237 {
238         window->data = 0;
239         window->success_counter = 0;
240         window->success_ratio = IWL_INVALID_VALUE;
241         window->counter = 0;
242         window->average_tpt = IWL_INVALID_VALUE;
243         window->stamp = 0;
244 }
245
246 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
247 {
248         return (ant_type & valid_antenna) == ant_type;
249 }
250
251 /*
252  *      removes the old data from the statistics. All data that is older than
253  *      TID_MAX_TIME_DIFF, will be deleted.
254  */
255 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
256 {
257         /* The oldest age we want to keep */
258         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
259
260         while (tl->queue_count &&
261                (tl->time_stamp < oldest_time)) {
262                 tl->total -= tl->packet_count[tl->head];
263                 tl->packet_count[tl->head] = 0;
264                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
265                 tl->queue_count--;
266                 tl->head++;
267                 if (tl->head >= TID_QUEUE_MAX_SIZE)
268                         tl->head = 0;
269         }
270 }
271
272 /*
273  *      increment traffic load value for tid and also remove
274  *      any old values if passed the certain time period
275  */
276 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
277                            struct ieee80211_hdr *hdr)
278 {
279         u32 curr_time = jiffies_to_msecs(jiffies);
280         u32 time_diff;
281         s32 index;
282         struct iwl_traffic_load *tl = NULL;
283         u8 tid;
284
285         if (ieee80211_is_data_qos(hdr->frame_control)) {
286                 u8 *qc = ieee80211_get_qos_ctl(hdr);
287                 tid = qc[0] & 0xf;
288         } else
289                 return MAX_TID_COUNT;
290
291         tl = &lq_data->load[tid];
292
293         curr_time -= curr_time % TID_ROUND_VALUE;
294
295         /* Happens only for the first packet. Initialize the data */
296         if (!(tl->queue_count)) {
297                 tl->total = 1;
298                 tl->time_stamp = curr_time;
299                 tl->queue_count = 1;
300                 tl->head = 0;
301                 tl->packet_count[0] = 1;
302                 return MAX_TID_COUNT;
303         }
304
305         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
306         index = time_diff / TID_QUEUE_CELL_SPACING;
307
308         /* The history is too long: remove data that is older than */
309         /* TID_MAX_TIME_DIFF */
310         if (index >= TID_QUEUE_MAX_SIZE)
311                 rs_tl_rm_old_stats(tl, curr_time);
312
313         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
314         tl->packet_count[index] = tl->packet_count[index] + 1;
315         tl->total = tl->total + 1;
316
317         if ((index + 1) > tl->queue_count)
318                 tl->queue_count = index + 1;
319
320         return tid;
321 }
322
323 /*
324         get the traffic load value for tid
325 */
326 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
327 {
328         u32 curr_time = jiffies_to_msecs(jiffies);
329         u32 time_diff;
330         s32 index;
331         struct iwl_traffic_load *tl = NULL;
332
333         if (tid >= TID_MAX_LOAD_COUNT)
334                 return 0;
335
336         tl = &(lq_data->load[tid]);
337
338         curr_time -= curr_time % TID_ROUND_VALUE;
339
340         if (!(tl->queue_count))
341                 return 0;
342
343         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
344         index = time_diff / TID_QUEUE_CELL_SPACING;
345
346         /* The history is too long: remove data that is older than */
347         /* TID_MAX_TIME_DIFF */
348         if (index >= TID_QUEUE_MAX_SIZE)
349                 rs_tl_rm_old_stats(tl, curr_time);
350
351         return tl->total;
352 }
353
354 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
355                                       struct iwl_lq_sta *lq_data, u8 tid,
356                                       struct ieee80211_sta *sta)
357 {
358         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
359                 IWL_DEBUG_HT("Starting Tx agg: STA: %pM tid: %d\n",
360                                 sta->addr, tid);
361                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
362         }
363 }
364
365 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
366                               struct iwl_lq_sta *lq_data,
367                               struct ieee80211_sta *sta)
368 {
369         if ((tid < TID_MAX_LOAD_COUNT))
370                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
371         else if (tid == IWL_AGG_ALL_TID)
372                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
373                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
374 }
375
376 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
377 {
378         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
379                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
380                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
381 }
382
383 /**
384  * rs_collect_tx_data - Update the success/failure sliding window
385  *
386  * We keep a sliding window of the last 62 packets transmitted
387  * at this rate.  window->data contains the bitmask of successful
388  * packets.
389  */
390 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
391                               int scale_index, s32 tpt, int retries,
392                               int successes)
393 {
394         struct iwl_rate_scale_data *window = NULL;
395         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
396         s32 fail_count;
397
398         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
399                 return -EINVAL;
400
401         /* Select data for current tx bit rate */
402         window = &(windows[scale_index]);
403
404         /*
405          * Keep track of only the latest 62 tx frame attempts in this rate's
406          * history window; anything older isn't really relevant any more.
407          * If we have filled up the sliding window, drop the oldest attempt;
408          * if the oldest attempt (highest bit in bitmap) shows "success",
409          * subtract "1" from the success counter (this is the main reason
410          * we keep these bitmaps!).
411          */
412         while (retries > 0) {
413                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
414
415                         /* remove earliest */
416                         window->counter = IWL_RATE_MAX_WINDOW - 1;
417
418                         if (window->data & mask) {
419                                 window->data &= ~mask;
420                                 window->success_counter--;
421                         }
422                 }
423
424                 /* Increment frames-attempted counter */
425                 window->counter++;
426
427                 /* Shift bitmap by one frame (throw away oldest history),
428                  * OR in "1", and increment "success" if this
429                  * frame was successful. */
430                 window->data <<= 1;
431                 if (successes > 0) {
432                         window->success_counter++;
433                         window->data |= 0x1;
434                         successes--;
435                 }
436
437                 retries--;
438         }
439
440         /* Calculate current success ratio, avoid divide-by-0! */
441         if (window->counter > 0)
442                 window->success_ratio = 128 * (100 * window->success_counter)
443                                         / window->counter;
444         else
445                 window->success_ratio = IWL_INVALID_VALUE;
446
447         fail_count = window->counter - window->success_counter;
448
449         /* Calculate average throughput, if we have enough history. */
450         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
451             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
452                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
453         else
454                 window->average_tpt = IWL_INVALID_VALUE;
455
456         /* Tag this window as having been updated */
457         window->stamp = jiffies;
458
459         return 0;
460 }
461
462 /*
463  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
464  */
465 /* FIXME:RS:remove this function and put the flags statically in the table */
466 static u32 rate_n_flags_from_tbl(struct iwl_scale_tbl_info *tbl,
467                                        int index, u8 use_green)
468 {
469         u32 rate_n_flags = 0;
470
471         if (is_legacy(tbl->lq_type)) {
472                 rate_n_flags = iwl_rates[index].plcp;
473                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
474                         rate_n_flags |= RATE_MCS_CCK_MSK;
475
476         } else if (is_Ht(tbl->lq_type)) {
477                 if (index > IWL_LAST_OFDM_RATE) {
478                         IWL_ERROR("invalid HT rate index %d\n", index);
479                         index = IWL_LAST_OFDM_RATE;
480                 }
481                 rate_n_flags = RATE_MCS_HT_MSK;
482
483                 if (is_siso(tbl->lq_type))
484                         rate_n_flags |= iwl_rates[index].plcp_siso;
485                 else if (is_mimo2(tbl->lq_type))
486                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
487                 else
488                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
489         } else {
490                 IWL_ERROR("Invalid tbl->lq_type %d\n", tbl->lq_type);
491         }
492
493         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
494                                                      RATE_MCS_ANT_ABC_MSK);
495
496         if (is_Ht(tbl->lq_type)) {
497                 if (tbl->is_fat) {
498                         if (tbl->is_dup)
499                                 rate_n_flags |= RATE_MCS_DUP_MSK;
500                         else
501                                 rate_n_flags |= RATE_MCS_FAT_MSK;
502                 }
503                 if (tbl->is_SGI)
504                         rate_n_flags |= RATE_MCS_SGI_MSK;
505
506                 if (use_green) {
507                         rate_n_flags |= RATE_MCS_GF_MSK;
508                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
509                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
510                                 IWL_ERROR("GF was set with SGI:SISO\n");
511                         }
512                 }
513         }
514         return rate_n_flags;
515 }
516
517 /*
518  * Interpret uCode API's rate_n_flags format,
519  * fill "search" or "active" tx mode table.
520  */
521 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
522                                     enum ieee80211_band band,
523                                     struct iwl_scale_tbl_info *tbl,
524                                     int *rate_idx)
525 {
526         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
527         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
528         u8 mcs;
529
530         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
531
532         if (*rate_idx  == IWL_RATE_INVALID) {
533                 *rate_idx = -1;
534                 return -EINVAL;
535         }
536         tbl->is_SGI = 0;        /* default legacy setup */
537         tbl->is_fat = 0;
538         tbl->is_dup = 0;
539         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
540         tbl->lq_type = LQ_NONE;
541
542         /* legacy rate format */
543         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
544                 if (num_of_ant == 1) {
545                         if (band == IEEE80211_BAND_5GHZ)
546                                 tbl->lq_type = LQ_A;
547                         else
548                                 tbl->lq_type = LQ_G;
549                 }
550         /* HT rate format */
551         } else {
552                 if (rate_n_flags & RATE_MCS_SGI_MSK)
553                         tbl->is_SGI = 1;
554
555                 if ((rate_n_flags & RATE_MCS_FAT_MSK) ||
556                     (rate_n_flags & RATE_MCS_DUP_MSK))
557                         tbl->is_fat = 1;
558
559                 if (rate_n_flags & RATE_MCS_DUP_MSK)
560                         tbl->is_dup = 1;
561
562                 mcs = rs_extract_rate(rate_n_flags);
563
564                 /* SISO */
565                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
566                         if (num_of_ant == 1)
567                                 tbl->lq_type = LQ_SISO; /*else NONE*/
568                 /* MIMO2 */
569                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
570                         if (num_of_ant == 2)
571                                 tbl->lq_type = LQ_MIMO2;
572                 /* MIMO3 */
573                 } else {
574                         if (num_of_ant == 3)
575                                 tbl->lq_type = LQ_MIMO3;
576                 }
577         }
578         return 0;
579 }
580
581 /* switch to another antenna/antennas and return 1 */
582 /* if no other valid antenna found, return 0 */
583 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
584                              struct iwl_scale_tbl_info *tbl)
585 {
586         u8 new_ant_type;
587
588         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
589                 return 0;
590
591         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
592                 return 0;
593
594         new_ant_type = ant_toggle_lookup[tbl->ant_type];
595
596         while ((new_ant_type != tbl->ant_type) &&
597                !rs_is_valid_ant(valid_ant, new_ant_type))
598                 new_ant_type = ant_toggle_lookup[new_ant_type];
599
600         if (new_ant_type == tbl->ant_type)
601                 return 0;
602
603         tbl->ant_type = new_ant_type;
604         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
605         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
606         return 1;
607 }
608
609 /* FIXME:RS: in 4965 we don't use greenfield at all */
610 /* FIXME:RS: don't use greenfield for now in TX */
611 #if 0
612 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
613 {
614         return (conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
615                 priv->current_ht_config.is_green_field &&
616                 !priv->current_ht_config.non_GF_STA_present;
617 }
618 #endif
619 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
620 {
621         return 0;
622 }
623
624 /**
625  * rs_get_supported_rates - get the available rates
626  *
627  * if management frame or broadcast frame only return
628  * basic available rates.
629  *
630  */
631 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
632                                   struct ieee80211_hdr *hdr,
633                                   enum iwl_table_type rate_type)
634 {
635         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
636             lq_sta->active_rate_basic)
637                 return lq_sta->active_rate_basic;
638
639         if (is_legacy(rate_type)) {
640                 return lq_sta->active_legacy_rate;
641         } else {
642                 if (is_siso(rate_type))
643                         return lq_sta->active_siso_rate;
644                 else if (is_mimo2(rate_type))
645                         return lq_sta->active_mimo2_rate;
646                 else
647                         return lq_sta->active_mimo3_rate;
648         }
649 }
650
651 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
652                                 int rate_type)
653 {
654         u8 high = IWL_RATE_INVALID;
655         u8 low = IWL_RATE_INVALID;
656
657         /* 802.11A or ht walks to the next literal adjacent rate in
658          * the rate table */
659         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
660                 int i;
661                 u32 mask;
662
663                 /* Find the previous rate that is in the rate mask */
664                 i = index - 1;
665                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
666                         if (rate_mask & mask) {
667                                 low = i;
668                                 break;
669                         }
670                 }
671
672                 /* Find the next rate that is in the rate mask */
673                 i = index + 1;
674                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
675                         if (rate_mask & mask) {
676                                 high = i;
677                                 break;
678                         }
679                 }
680
681                 return (high << 8) | low;
682         }
683
684         low = index;
685         while (low != IWL_RATE_INVALID) {
686                 low = iwl_rates[low].prev_rs;
687                 if (low == IWL_RATE_INVALID)
688                         break;
689                 if (rate_mask & (1 << low))
690                         break;
691                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
692         }
693
694         high = index;
695         while (high != IWL_RATE_INVALID) {
696                 high = iwl_rates[high].next_rs;
697                 if (high == IWL_RATE_INVALID)
698                         break;
699                 if (rate_mask & (1 << high))
700                         break;
701                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
702         }
703
704         return (high << 8) | low;
705 }
706
707 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
708                              struct iwl_scale_tbl_info *tbl,
709                              u8 scale_index, u8 ht_possible)
710 {
711         s32 low;
712         u16 rate_mask;
713         u16 high_low;
714         u8 switch_to_legacy = 0;
715         u8 is_green = lq_sta->is_green;
716
717         /* check if we need to switch from HT to legacy rates.
718          * assumption is that mandatory rates (1Mbps or 6Mbps)
719          * are always supported (spec demand) */
720         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
721                 switch_to_legacy = 1;
722                 scale_index = rs_ht_to_legacy[scale_index];
723                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
724                         tbl->lq_type = LQ_A;
725                 else
726                         tbl->lq_type = LQ_G;
727
728                 if (num_of_ant(tbl->ant_type) > 1)
729                         tbl->ant_type = ANT_A;/*FIXME:RS*/
730
731                 tbl->is_fat = 0;
732                 tbl->is_SGI = 0;
733         }
734
735         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
736
737         /* Mask with station rate restriction */
738         if (is_legacy(tbl->lq_type)) {
739                 /* supp_rates has no CCK bits in A mode */
740                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
741                         rate_mask  = (u16)(rate_mask &
742                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
743                 else
744                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
745         }
746
747         /* If we switched from HT to legacy, check current rate */
748         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
749                 low = scale_index;
750                 goto out;
751         }
752
753         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
754                                         tbl->lq_type);
755         low = high_low & 0xff;
756
757         if (low == IWL_RATE_INVALID)
758                 low = scale_index;
759
760 out:
761         return rate_n_flags_from_tbl(tbl, low, is_green);
762 }
763
764 /*
765  * mac80211 sends us Tx status
766  */
767 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
768                          struct ieee80211_sta *sta, void *priv_sta,
769                          struct sk_buff *skb)
770 {
771         int status;
772         u8 retries;
773         int rs_index, index = 0;
774         struct iwl_lq_sta *lq_sta = priv_sta;
775         struct iwl_link_quality_cmd *table;
776         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
777         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
778         struct ieee80211_hw *hw = priv->hw;
779         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
780         struct iwl_rate_scale_data *window = NULL;
781         struct iwl_rate_scale_data *search_win = NULL;
782         u32 tx_rate;
783         struct iwl_scale_tbl_info tbl_type;
784         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
785         u8 active_index = 0;
786         s32 tpt = 0;
787
788         IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
789
790         if (!ieee80211_is_data(hdr->frame_control) ||
791             is_multicast_ether_addr(hdr->addr1))
792                 return;
793
794         /* This packet was aggregated but doesn't carry rate scale info */
795         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
796             !(info->flags & IEEE80211_TX_STAT_AMPDU))
797                 return;
798
799         retries = info->status.rates[0].count - 1;
800
801         if (retries > 15)
802                 retries = 15;
803
804         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
805             !lq_sta->ibss_sta_added)
806                 goto out;
807
808         table = &lq_sta->lq;
809         active_index = lq_sta->active_tbl;
810
811         curr_tbl = &(lq_sta->lq_info[active_index]);
812         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
813         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
814         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
815
816         /*
817          * Ignore this Tx frame response if its initial rate doesn't match
818          * that of latest Link Quality command.  There may be stragglers
819          * from a previous Link Quality command, but we're no longer interested
820          * in those; they're either from the "active" mode while we're trying
821          * to check "search" mode, or a prior "search" mode after we've moved
822          * to a new "search" mode (which might become the new "active" mode).
823          */
824         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
825         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
826         if (priv->band == IEEE80211_BAND_5GHZ)
827                 rs_index -= IWL_FIRST_OFDM_RATE;
828
829         if ((info->status.rates[0].idx < 0) ||
830             (tbl_type.is_SGI != !!(info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)) ||
831             (tbl_type.is_fat != !!(info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
832             (tbl_type.is_dup != !!(info->status.rates[0].flags & IEEE80211_TX_RC_DUP_DATA)) ||
833             (tbl_type.ant_type != info->antenna_sel_tx) ||
834             (!!(tx_rate & RATE_MCS_HT_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) ||
835             (!!(tx_rate & RATE_MCS_GF_MSK) != !!(info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
836             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
837              hw->wiphy->bands[info->band]->bitrates[info->status.rates[0].idx].bitrate)) {
838                 IWL_DEBUG_RATE("initial rate does not match 0x%x\n", tx_rate);
839                 /* the last LQ command could failed so the LQ in ucode not
840                  * the same in driver sync up
841                  */
842                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
843                 goto out;
844         }
845
846         /* Update frame history window with "failure" for each Tx retry. */
847         while (retries) {
848                 /* Look up the rate and other info used for each tx attempt.
849                  * Each tx attempt steps one entry deeper in the rate table. */
850                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
851                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
852                                           &tbl_type, &rs_index);
853
854                 /* If type matches "search" table,
855                  * add failure to "search" history */
856                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
857                     (tbl_type.ant_type == search_tbl->ant_type) &&
858                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
859                         if (search_tbl->expected_tpt)
860                                 tpt = search_tbl->expected_tpt[rs_index];
861                         else
862                                 tpt = 0;
863                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
864
865                 /* Else if type matches "current/active" table,
866                  * add failure to "current/active" history */
867                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
868                            (tbl_type.ant_type == curr_tbl->ant_type) &&
869                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
870                         if (curr_tbl->expected_tpt)
871                                 tpt = curr_tbl->expected_tpt[rs_index];
872                         else
873                                 tpt = 0;
874                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
875                 }
876
877                 /* If not searching for a new mode, increment failed counter
878                  * ... this helps determine when to start searching again */
879                 if (lq_sta->stay_in_tbl)
880                         lq_sta->total_failed++;
881                 --retries;
882                 index++;
883
884         }
885
886         /*
887          * Find (by rate) the history window to update with final Tx attempt;
888          * if Tx was successful first try, use original rate,
889          * else look up the rate that was, finally, successful.
890          */
891         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
892         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
893
894         /* Update frame history window with "success" if Tx got ACKed ... */
895         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
896
897         /* If type matches "search" table,
898          * add final tx status to "search" history */
899         if ((tbl_type.lq_type == search_tbl->lq_type) &&
900             (tbl_type.ant_type == search_tbl->ant_type) &&
901             (tbl_type.is_SGI == search_tbl->is_SGI)) {
902                 if (search_tbl->expected_tpt)
903                         tpt = search_tbl->expected_tpt[rs_index];
904                 else
905                         tpt = 0;
906                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
907                         rs_collect_tx_data(search_win, rs_index, tpt,
908                                            info->status.ampdu_ack_len,
909                                            info->status.ampdu_ack_map);
910                 else
911                         rs_collect_tx_data(search_win, rs_index, tpt,
912                                            1, status);
913         /* Else if type matches "current/active" table,
914          * add final tx status to "current/active" history */
915         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
916                    (tbl_type.ant_type == curr_tbl->ant_type) &&
917                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
918                 if (curr_tbl->expected_tpt)
919                         tpt = curr_tbl->expected_tpt[rs_index];
920                 else
921                         tpt = 0;
922                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
923                         rs_collect_tx_data(window, rs_index, tpt,
924                                            info->status.ampdu_ack_len,
925                                            info->status.ampdu_ack_map);
926                 else
927                         rs_collect_tx_data(window, rs_index, tpt,
928                                            1, status);
929         }
930
931         /* If not searching for new mode, increment success/failed counter
932          * ... these help determine when to start searching again */
933         if (lq_sta->stay_in_tbl) {
934                 if (info->flags & IEEE80211_TX_CTL_AMPDU) {
935                         lq_sta->total_success += info->status.ampdu_ack_map;
936                         lq_sta->total_failed +=
937                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
938                 } else {
939                         if (status)
940                                 lq_sta->total_success++;
941                         else
942                                 lq_sta->total_failed++;
943                 }
944         }
945
946         /* See if there's a better rate or modulation mode to try. */
947         if (sta && sta->supp_rates[sband->band])
948                 rs_rate_scale_perform(priv, hdr, sta, lq_sta);
949 out:
950         return;
951 }
952
953 /*
954  * Begin a period of staying with a selected modulation mode.
955  * Set "stay_in_tbl" flag to prevent any mode switches.
956  * Set frame tx success limits according to legacy vs. high-throughput,
957  * and reset overall (spanning all rates) tx success history statistics.
958  * These control how long we stay using same modulation mode before
959  * searching for a new mode.
960  */
961 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
962                                  struct iwl_lq_sta *lq_sta)
963 {
964         IWL_DEBUG_RATE("we are staying in the same table\n");
965         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
966         if (is_legacy) {
967                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
968                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
969                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
970         } else {
971                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
972                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
973                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
974         }
975         lq_sta->table_count = 0;
976         lq_sta->total_failed = 0;
977         lq_sta->total_success = 0;
978 }
979
980 /*
981  * Find correct throughput table for given mode of modulation
982  */
983 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
984                                       struct iwl_scale_tbl_info *tbl)
985 {
986         if (is_legacy(tbl->lq_type)) {
987                 if (!is_a_band(tbl->lq_type))
988                         tbl->expected_tpt = expected_tpt_G;
989                 else
990                         tbl->expected_tpt = expected_tpt_A;
991         } else if (is_siso(tbl->lq_type)) {
992                 if (tbl->is_fat && !lq_sta->is_dup)
993                         if (tbl->is_SGI)
994                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
995                         else
996                                 tbl->expected_tpt = expected_tpt_siso40MHz;
997                 else if (tbl->is_SGI)
998                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
999                 else
1000                         tbl->expected_tpt = expected_tpt_siso20MHz;
1001
1002         } else if (is_mimo(tbl->lq_type)) { /* FIXME:need to separate mimo2/3 */
1003                 if (tbl->is_fat && !lq_sta->is_dup)
1004                         if (tbl->is_SGI)
1005                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
1006                         else
1007                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
1008                 else if (tbl->is_SGI)
1009                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
1010                 else
1011                         tbl->expected_tpt = expected_tpt_mimo20MHz;
1012         } else
1013                 tbl->expected_tpt = expected_tpt_G;
1014 }
1015
1016 /*
1017  * Find starting rate for new "search" high-throughput mode of modulation.
1018  * Goal is to find lowest expected rate (under perfect conditions) that is
1019  * above the current measured throughput of "active" mode, to give new mode
1020  * a fair chance to prove itself without too many challenges.
1021  *
1022  * This gets called when transitioning to more aggressive modulation
1023  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1024  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1025  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1026  * bit rate will typically need to increase, but not if performance was bad.
1027  */
1028 static s32 rs_get_best_rate(struct iwl_priv *priv,
1029                             struct iwl_lq_sta *lq_sta,
1030                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1031                             u16 rate_mask, s8 index)
1032 {
1033         /* "active" values */
1034         struct iwl_scale_tbl_info *active_tbl =
1035             &(lq_sta->lq_info[lq_sta->active_tbl]);
1036         s32 active_sr = active_tbl->win[index].success_ratio;
1037         s32 active_tpt = active_tbl->expected_tpt[index];
1038
1039         /* expected "search" throughput */
1040         s32 *tpt_tbl = tbl->expected_tpt;
1041
1042         s32 new_rate, high, low, start_hi;
1043         u16 high_low;
1044         s8 rate = index;
1045
1046         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1047
1048         for (; ;) {
1049                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1050                                                 tbl->lq_type);
1051
1052                 low = high_low & 0xff;
1053                 high = (high_low >> 8) & 0xff;
1054
1055                 /*
1056                  * Lower the "search" bit rate, to give new "search" mode
1057                  * approximately the same throughput as "active" if:
1058                  *
1059                  * 1) "Active" mode has been working modestly well (but not
1060                  *    great), and expected "search" throughput (under perfect
1061                  *    conditions) at candidate rate is above the actual
1062                  *    measured "active" throughput (but less than expected
1063                  *    "active" throughput under perfect conditions).
1064                  * OR
1065                  * 2) "Active" mode has been working perfectly or very well
1066                  *    and expected "search" throughput (under perfect
1067                  *    conditions) at candidate rate is above expected
1068                  *    "active" throughput (under perfect conditions).
1069                  */
1070                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1071                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1072                       (active_sr <= IWL_RATE_HIGH_TH) &&
1073                       (tpt_tbl[rate] <= active_tpt))) ||
1074                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1075                      (tpt_tbl[rate] > active_tpt))) {
1076
1077                         /* (2nd or later pass)
1078                          * If we've already tried to raise the rate, and are
1079                          * now trying to lower it, use the higher rate. */
1080                         if (start_hi != IWL_RATE_INVALID) {
1081                                 new_rate = start_hi;
1082                                 break;
1083                         }
1084
1085                         new_rate = rate;
1086
1087                         /* Loop again with lower rate */
1088                         if (low != IWL_RATE_INVALID)
1089                                 rate = low;
1090
1091                         /* Lower rate not available, use the original */
1092                         else
1093                                 break;
1094
1095                 /* Else try to raise the "search" rate to match "active" */
1096                 } else {
1097                         /* (2nd or later pass)
1098                          * If we've already tried to lower the rate, and are
1099                          * now trying to raise it, use the lower rate. */
1100                         if (new_rate != IWL_RATE_INVALID)
1101                                 break;
1102
1103                         /* Loop again with higher rate */
1104                         else if (high != IWL_RATE_INVALID) {
1105                                 start_hi = high;
1106                                 rate = high;
1107
1108                         /* Higher rate not available, use the original */
1109                         } else {
1110                                 new_rate = rate;
1111                                 break;
1112                         }
1113                 }
1114         }
1115
1116         return new_rate;
1117 }
1118
1119 /*
1120  * Set up search table for MIMO
1121  */
1122 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1123                              struct iwl_lq_sta *lq_sta,
1124                              struct ieee80211_conf *conf,
1125                              struct ieee80211_sta *sta,
1126                              struct iwl_scale_tbl_info *tbl, int index)
1127 {
1128         u16 rate_mask;
1129         s32 rate;
1130         s8 is_green = lq_sta->is_green;
1131
1132         if (!conf->ht.enabled || !sta->ht_cap.ht_supported)
1133                 return -1;
1134
1135         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1136                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1137                 return -1;
1138
1139         /* Need both Tx chains/antennas to support MIMO */
1140         if (priv->hw_params.tx_chains_num < 2)
1141                 return -1;
1142
1143         IWL_DEBUG_RATE("LQ: try to switch to MIMO2\n");
1144
1145         tbl->lq_type = LQ_MIMO2;
1146         tbl->is_dup = lq_sta->is_dup;
1147         tbl->action = 0;
1148         rate_mask = lq_sta->active_mimo2_rate;
1149
1150         if (priv->current_ht_config.supported_chan_width
1151                                         == IWL_CHANNEL_WIDTH_40MHZ)
1152                 tbl->is_fat = 1;
1153         else
1154                 tbl->is_fat = 0;
1155
1156         /* FIXME: - don't toggle SGI here
1157         if (tbl->is_fat) {
1158                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1159                         tbl->is_SGI = 1;
1160                 else
1161                         tbl->is_SGI = 0;
1162         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1163                 tbl->is_SGI = 1;
1164         else
1165                 tbl->is_SGI = 0;
1166         */
1167
1168         rs_set_expected_tpt_table(lq_sta, tbl);
1169
1170         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1171
1172         IWL_DEBUG_RATE("LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1173
1174         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1175                 IWL_DEBUG_RATE("Can't switch with index %d rate mask %x\n",
1176                                                 rate, rate_mask);
1177                 return -1;
1178         }
1179         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1180
1181         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1182                      tbl->current_rate, is_green);
1183         return 0;
1184 }
1185
1186 /*
1187  * Set up search table for SISO
1188  */
1189 static int rs_switch_to_siso(struct iwl_priv *priv,
1190                              struct iwl_lq_sta *lq_sta,
1191                              struct ieee80211_conf *conf,
1192                              struct ieee80211_sta *sta,
1193                              struct iwl_scale_tbl_info *tbl, int index)
1194 {
1195         u16 rate_mask;
1196         u8 is_green = lq_sta->is_green;
1197         s32 rate;
1198
1199         if (!conf->ht.enabled || !sta->ht_cap.ht_supported)
1200                 return -1;
1201
1202         IWL_DEBUG_RATE("LQ: try to switch to SISO\n");
1203
1204         tbl->is_dup = lq_sta->is_dup;
1205         tbl->lq_type = LQ_SISO;
1206         tbl->action = 0;
1207         rate_mask = lq_sta->active_siso_rate;
1208
1209         if (priv->current_ht_config.supported_chan_width
1210             == IWL_CHANNEL_WIDTH_40MHZ)
1211                 tbl->is_fat = 1;
1212         else
1213                 tbl->is_fat = 0;
1214
1215         /* FIXME: - don't toggle SGI here
1216         if (tbl->is_fat) {
1217                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1218                         tbl->is_SGI = 1;
1219                 else
1220                         tbl->is_SGI = 0;
1221         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1222                 tbl->is_SGI = 1;
1223         else
1224                 tbl->is_SGI = 0;
1225         */
1226
1227         if (is_green)
1228                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1229
1230         rs_set_expected_tpt_table(lq_sta, tbl);
1231         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1232
1233         IWL_DEBUG_RATE("LQ: get best rate %d mask %X\n", rate, rate_mask);
1234         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1235                 IWL_DEBUG_RATE("can not switch with index %d rate mask %x\n",
1236                              rate, rate_mask);
1237                 return -1;
1238         }
1239         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1240         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1241                      tbl->current_rate, is_green);
1242         return 0;
1243 }
1244
1245 /*
1246  * Try to switch to new modulation mode from legacy
1247  */
1248 static int rs_move_legacy_other(struct iwl_priv *priv,
1249                                 struct iwl_lq_sta *lq_sta,
1250                                 struct ieee80211_conf *conf,
1251                                 struct ieee80211_sta *sta,
1252                                 int index)
1253 {
1254         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1255         struct iwl_scale_tbl_info *search_tbl =
1256                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1257         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1258         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1259                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1260         u8 start_action = tbl->action;
1261         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1262         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1263         int ret = 0;
1264
1265         for (; ;) {
1266                 switch (tbl->action) {
1267                 case IWL_LEGACY_SWITCH_ANTENNA1:
1268                 case IWL_LEGACY_SWITCH_ANTENNA2:
1269                         IWL_DEBUG_RATE("LQ: Legacy toggle Antenna\n");
1270
1271                         lq_sta->action_counter++;
1272
1273                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1274                                                         tx_chains_num <= 1) ||
1275                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1276                                                         tx_chains_num <= 2))
1277                                 break;
1278
1279                         /* Don't change antenna if success has been great */
1280                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1281                                 break;
1282
1283                         /* Set up search table to try other antenna */
1284                         memcpy(search_tbl, tbl, sz);
1285
1286                         if (rs_toggle_antenna(valid_tx_ant,
1287                                 &search_tbl->current_rate, search_tbl)) {
1288                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1289                                 goto out;
1290                         }
1291                         break;
1292                 case IWL_LEGACY_SWITCH_SISO:
1293                         IWL_DEBUG_RATE("LQ: Legacy switch to SISO\n");
1294
1295                         /* Set up search table to try SISO */
1296                         memcpy(search_tbl, tbl, sz);
1297                         search_tbl->is_SGI = 0;
1298                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1299                                                  search_tbl, index);
1300                         if (!ret) {
1301                                 lq_sta->action_counter = 0;
1302                                 goto out;
1303                         }
1304
1305                         break;
1306                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1307                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1308                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1309                         IWL_DEBUG_RATE("LQ: Legacy switch to MIMO2\n");
1310
1311                         /* Set up search table to try MIMO */
1312                         memcpy(search_tbl, tbl, sz);
1313                         search_tbl->is_SGI = 0;
1314
1315                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1316                                 search_tbl->ant_type = ANT_AB;
1317                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1318                                 search_tbl->ant_type = ANT_AC;
1319                         else
1320                                 search_tbl->ant_type = ANT_BC;
1321
1322                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1323                                 break;
1324
1325                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1326                                                  search_tbl, index);
1327                         if (!ret) {
1328                                 lq_sta->action_counter = 0;
1329                                 goto out;
1330                         }
1331                         break;
1332                 }
1333                 tbl->action++;
1334                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1335                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1336
1337                 if (tbl->action == start_action)
1338                         break;
1339
1340         }
1341         search_tbl->lq_type = LQ_NONE;
1342         return 0;
1343
1344 out:
1345         lq_sta->search_better_tbl = 1;
1346         tbl->action++;
1347         if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1348                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1349         return 0;
1350
1351 }
1352
1353 /*
1354  * Try to switch to new modulation mode from SISO
1355  */
1356 static int rs_move_siso_to_other(struct iwl_priv *priv,
1357                                  struct iwl_lq_sta *lq_sta,
1358                                  struct ieee80211_conf *conf,
1359                                  struct ieee80211_sta *sta, int index)
1360 {
1361         u8 is_green = lq_sta->is_green;
1362         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1363         struct iwl_scale_tbl_info *search_tbl =
1364                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1365         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1366         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1367                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1368         u8 start_action = tbl->action;
1369         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1370         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1371         int ret;
1372
1373         for (;;) {
1374                 lq_sta->action_counter++;
1375                 switch (tbl->action) {
1376                 case IWL_SISO_SWITCH_ANTENNA1:
1377                 case IWL_SISO_SWITCH_ANTENNA2:
1378                         IWL_DEBUG_RATE("LQ: SISO toggle Antenna\n");
1379
1380                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1381                                                         tx_chains_num <= 1) ||
1382                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1383                                                         tx_chains_num <= 2))
1384                                 break;
1385
1386                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1387                                 break;
1388
1389                         memcpy(search_tbl, tbl, sz);
1390                         if (rs_toggle_antenna(valid_tx_ant,
1391                                        &search_tbl->current_rate, search_tbl))
1392                                 goto out;
1393                         break;
1394                 case IWL_SISO_SWITCH_MIMO2_AB:
1395                 case IWL_SISO_SWITCH_MIMO2_AC:
1396                 case IWL_SISO_SWITCH_MIMO2_BC:
1397                         IWL_DEBUG_RATE("LQ: SISO switch to MIMO2\n");
1398                         memcpy(search_tbl, tbl, sz);
1399                         search_tbl->is_SGI = 0;
1400
1401                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1402                                 search_tbl->ant_type = ANT_AB;
1403                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1404                                 search_tbl->ant_type = ANT_AC;
1405                         else
1406                                 search_tbl->ant_type = ANT_BC;
1407
1408                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1409                                 break;
1410
1411                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1412                                                  search_tbl, index);
1413                         if (!ret)
1414                                 goto out;
1415                         break;
1416                 case IWL_SISO_SWITCH_GI:
1417                         if (!tbl->is_fat &&
1418                                 !(priv->current_ht_config.sgf &
1419                                                 HT_SHORT_GI_20MHZ))
1420                                 break;
1421                         if (tbl->is_fat &&
1422                                 !(priv->current_ht_config.sgf &
1423                                                 HT_SHORT_GI_40MHZ))
1424                                 break;
1425
1426                         IWL_DEBUG_RATE("LQ: SISO toggle SGI/NGI\n");
1427
1428                         memcpy(search_tbl, tbl, sz);
1429                         if (is_green) {
1430                                 if (!tbl->is_SGI)
1431                                         break;
1432                                 else
1433                                         IWL_ERROR("SGI was set in GF+SISO\n");
1434                         }
1435                         search_tbl->is_SGI = !tbl->is_SGI;
1436                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1437                         if (tbl->is_SGI) {
1438                                 s32 tpt = lq_sta->last_tpt / 100;
1439                                 if (tpt >= search_tbl->expected_tpt[index])
1440                                         break;
1441                         }
1442                         search_tbl->current_rate = rate_n_flags_from_tbl(
1443                                                 search_tbl, index, is_green);
1444                         goto out;
1445                 }
1446                 tbl->action++;
1447                 if (tbl->action > IWL_SISO_SWITCH_GI)
1448                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1449
1450                 if (tbl->action == start_action)
1451                         break;
1452         }
1453         search_tbl->lq_type = LQ_NONE;
1454         return 0;
1455
1456  out:
1457         lq_sta->search_better_tbl = 1;
1458         tbl->action++;
1459         if (tbl->action > IWL_SISO_SWITCH_GI)
1460                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1461         return 0;
1462 }
1463
1464 /*
1465  * Try to switch to new modulation mode from MIMO
1466  */
1467 static int rs_move_mimo_to_other(struct iwl_priv *priv,
1468                                  struct iwl_lq_sta *lq_sta,
1469                                  struct ieee80211_conf *conf,
1470                                  struct ieee80211_sta *sta, int index)
1471 {
1472         s8 is_green = lq_sta->is_green;
1473         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1474         struct iwl_scale_tbl_info *search_tbl =
1475                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1476         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1477         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1478                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1479         u8 start_action = tbl->action;
1480         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1481         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1482         int ret;
1483
1484         for (;;) {
1485                 lq_sta->action_counter++;
1486                 switch (tbl->action) {
1487                 case IWL_MIMO2_SWITCH_ANTENNA1:
1488                 case IWL_MIMO2_SWITCH_ANTENNA2:
1489                         IWL_DEBUG_RATE("LQ: MIMO toggle Antennas\n");
1490
1491                         if (tx_chains_num <= 2)
1492                                 break;
1493
1494                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1495                                 break;
1496
1497                         memcpy(search_tbl, tbl, sz);
1498                         if (rs_toggle_antenna(valid_tx_ant,
1499                                        &search_tbl->current_rate, search_tbl))
1500                                 goto out;
1501                         break;
1502                 case IWL_MIMO2_SWITCH_SISO_A:
1503                 case IWL_MIMO2_SWITCH_SISO_B:
1504                 case IWL_MIMO2_SWITCH_SISO_C:
1505                         IWL_DEBUG_RATE("LQ: MIMO2 switch to SISO\n");
1506
1507                         /* Set up new search table for SISO */
1508                         memcpy(search_tbl, tbl, sz);
1509
1510                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1511                                 search_tbl->ant_type = ANT_A;
1512                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1513                                 search_tbl->ant_type = ANT_B;
1514                         else
1515                                 search_tbl->ant_type = ANT_C;
1516
1517                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1518                                 break;
1519
1520                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1521                                                  search_tbl, index);
1522                         if (!ret)
1523                                 goto out;
1524
1525                         break;
1526
1527                 case IWL_MIMO2_SWITCH_GI:
1528                         if (!tbl->is_fat &&
1529                                 !(priv->current_ht_config.sgf &
1530                                                 HT_SHORT_GI_20MHZ))
1531                                 break;
1532                         if (tbl->is_fat &&
1533                                 !(priv->current_ht_config.sgf &
1534                                                 HT_SHORT_GI_40MHZ))
1535                                 break;
1536
1537                         IWL_DEBUG_RATE("LQ: MIMO toggle SGI/NGI\n");
1538
1539                         /* Set up new search table for MIMO */
1540                         memcpy(search_tbl, tbl, sz);
1541                         search_tbl->is_SGI = !tbl->is_SGI;
1542                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1543                         /*
1544                          * If active table already uses the fastest possible
1545                          * modulation (dual stream with short guard interval),
1546                          * and it's working well, there's no need to look
1547                          * for a better type of modulation!
1548                          */
1549                         if (tbl->is_SGI) {
1550                                 s32 tpt = lq_sta->last_tpt / 100;
1551                                 if (tpt >= search_tbl->expected_tpt[index])
1552                                         break;
1553                         }
1554                         search_tbl->current_rate = rate_n_flags_from_tbl(
1555                                                 search_tbl, index, is_green);
1556                         goto out;
1557
1558                 }
1559                 tbl->action++;
1560                 if (tbl->action > IWL_MIMO2_SWITCH_GI)
1561                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1562
1563                 if (tbl->action == start_action)
1564                         break;
1565         }
1566         search_tbl->lq_type = LQ_NONE;
1567         return 0;
1568  out:
1569         lq_sta->search_better_tbl = 1;
1570         tbl->action++;
1571         if (tbl->action > IWL_MIMO2_SWITCH_GI)
1572                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1573         return 0;
1574
1575 }
1576
1577 /*
1578  * Check whether we should continue using same modulation mode, or
1579  * begin search for a new mode, based on:
1580  * 1) # tx successes or failures while using this mode
1581  * 2) # times calling this function
1582  * 3) elapsed time in this mode (not used, for now)
1583  */
1584 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1585 {
1586         struct iwl_scale_tbl_info *tbl;
1587         int i;
1588         int active_tbl;
1589         int flush_interval_passed = 0;
1590         struct iwl_priv *priv;
1591
1592         priv = lq_sta->drv;
1593         active_tbl = lq_sta->active_tbl;
1594
1595         tbl = &(lq_sta->lq_info[active_tbl]);
1596
1597         /* If we've been disallowing search, see if we should now allow it */
1598         if (lq_sta->stay_in_tbl) {
1599
1600                 /* Elapsed time using current modulation mode */
1601                 if (lq_sta->flush_timer)
1602                         flush_interval_passed =
1603                             time_after(jiffies,
1604                                        (unsigned long)(lq_sta->flush_timer +
1605                                         IWL_RATE_SCALE_FLUSH_INTVL));
1606
1607                 /*
1608                  * Check if we should allow search for new modulation mode.
1609                  * If many frames have failed or succeeded, or we've used
1610                  * this same modulation for a long time, allow search, and
1611                  * reset history stats that keep track of whether we should
1612                  * allow a new search.  Also (below) reset all bitmaps and
1613                  * stats in active history.
1614                  */
1615                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1616                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1617                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1618                      && (flush_interval_passed))) {
1619                         IWL_DEBUG_RATE("LQ: stay is expired %d %d %d\n:",
1620                                      lq_sta->total_failed,
1621                                      lq_sta->total_success,
1622                                      flush_interval_passed);
1623
1624                         /* Allow search for new mode */
1625                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1626                         lq_sta->total_failed = 0;
1627                         lq_sta->total_success = 0;
1628                         lq_sta->flush_timer = 0;
1629
1630                 /*
1631                  * Else if we've used this modulation mode enough repetitions
1632                  * (regardless of elapsed time or success/failure), reset
1633                  * history bitmaps and rate-specific stats for all rates in
1634                  * active table.
1635                  */
1636                 } else {
1637                         lq_sta->table_count++;
1638                         if (lq_sta->table_count >=
1639                             lq_sta->table_count_limit) {
1640                                 lq_sta->table_count = 0;
1641
1642                                 IWL_DEBUG_RATE("LQ: stay in table clear win\n");
1643                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1644                                         rs_rate_scale_clear_window(
1645                                                 &(tbl->win[i]));
1646                         }
1647                 }
1648
1649                 /* If transitioning to allow "search", reset all history
1650                  * bitmaps and stats in active table (this will become the new
1651                  * "search" table). */
1652                 if (!lq_sta->stay_in_tbl) {
1653                         for (i = 0; i < IWL_RATE_COUNT; i++)
1654                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1655                 }
1656         }
1657 }
1658
1659 /*
1660  * Do rate scaling and search for new modulation mode.
1661  */
1662 static void rs_rate_scale_perform(struct iwl_priv *priv,
1663                                   struct ieee80211_hdr *hdr,
1664                                   struct ieee80211_sta *sta,
1665                                   struct iwl_lq_sta *lq_sta)
1666 {
1667         struct ieee80211_hw *hw = priv->hw;
1668         struct ieee80211_conf *conf = &hw->conf;
1669         int low = IWL_RATE_INVALID;
1670         int high = IWL_RATE_INVALID;
1671         int index;
1672         int i;
1673         struct iwl_rate_scale_data *window = NULL;
1674         int current_tpt = IWL_INVALID_VALUE;
1675         int low_tpt = IWL_INVALID_VALUE;
1676         int high_tpt = IWL_INVALID_VALUE;
1677         u32 fail_count;
1678         s8 scale_action = 0;
1679         u16 rate_mask;
1680         u8 update_lq = 0;
1681         struct iwl_scale_tbl_info *tbl, *tbl1;
1682         u16 rate_scale_index_msk = 0;
1683         u32 rate;
1684         u8 is_green = 0;
1685         u8 active_tbl = 0;
1686         u8 done_search = 0;
1687         u16 high_low;
1688         s32 sr;
1689         u8 tid = MAX_TID_COUNT;
1690
1691         IWL_DEBUG_RATE("rate scale calculate new rate for skb\n");
1692
1693         /* Send management frames and broadcast/multicast data using
1694          * lowest rate. */
1695         /* TODO: this could probably be improved.. */
1696         if (!ieee80211_is_data(hdr->frame_control) ||
1697             is_multicast_ether_addr(hdr->addr1))
1698                 return;
1699
1700         if (!sta || !lq_sta)
1701                 return;
1702
1703         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1704
1705         tid = rs_tl_add_packet(lq_sta, hdr);
1706
1707         /*
1708          * Select rate-scale / modulation-mode table to work with in
1709          * the rest of this function:  "search" if searching for better
1710          * modulation mode, or "active" if doing rate scaling within a mode.
1711          */
1712         if (!lq_sta->search_better_tbl)
1713                 active_tbl = lq_sta->active_tbl;
1714         else
1715                 active_tbl = 1 - lq_sta->active_tbl;
1716
1717         tbl = &(lq_sta->lq_info[active_tbl]);
1718         is_green = lq_sta->is_green;
1719
1720         /* current tx rate */
1721         index = lq_sta->last_txrate_idx;
1722
1723         IWL_DEBUG_RATE("Rate scale index %d for type %d\n", index,
1724                        tbl->lq_type);
1725
1726         /* rates available for this association, and for modulation mode */
1727         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1728
1729         IWL_DEBUG_RATE("mask 0x%04X \n", rate_mask);
1730
1731         /* mask with station rate restriction */
1732         if (is_legacy(tbl->lq_type)) {
1733                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
1734                         /* supp_rates has no CCK bits in A mode */
1735                         rate_scale_index_msk = (u16) (rate_mask &
1736                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1737                 else
1738                         rate_scale_index_msk = (u16) (rate_mask &
1739                                                       lq_sta->supp_rates);
1740
1741         } else
1742                 rate_scale_index_msk = rate_mask;
1743
1744         if (!rate_scale_index_msk)
1745                 rate_scale_index_msk = rate_mask;
1746
1747         if (!((1 << index) & rate_scale_index_msk)) {
1748                 IWL_ERROR("Current Rate is not valid\n");
1749                 return;
1750         }
1751
1752         /* Get expected throughput table and history window for current rate */
1753         if (!tbl->expected_tpt) {
1754                 IWL_ERROR("tbl->expected_tpt is NULL\n");
1755                 return;
1756         }
1757
1758         window = &(tbl->win[index]);
1759
1760         /*
1761          * If there is not enough history to calculate actual average
1762          * throughput, keep analyzing results of more tx frames, without
1763          * changing rate or mode (bypass most of the rest of this function).
1764          * Set up new rate table in uCode only if old rate is not supported
1765          * in current association (use new rate found above).
1766          */
1767         fail_count = window->counter - window->success_counter;
1768         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1769                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
1770                 IWL_DEBUG_RATE("LQ: still below TH. succ=%d total=%d "
1771                                "for index %d\n",
1772                                window->success_counter, window->counter, index);
1773
1774                 /* Can't calculate this yet; not enough history */
1775                 window->average_tpt = IWL_INVALID_VALUE;
1776
1777                 /* Should we stay with this modulation mode,
1778                  * or search for a new one? */
1779                 rs_stay_in_table(lq_sta);
1780
1781                 goto out;
1782         }
1783
1784         /* Else we have enough samples; calculate estimate of
1785          * actual average throughput */
1786
1787         BUG_ON(window->average_tpt != ((window->success_ratio *
1788                         tbl->expected_tpt[index] + 64) / 128));
1789
1790         /* If we are searching for better modulation mode, check success. */
1791         if (lq_sta->search_better_tbl) {
1792
1793                 /* If good success, continue using the "search" mode;
1794                  * no need to send new link quality command, since we're
1795                  * continuing to use the setup that we've been trying. */
1796                 if (window->average_tpt > lq_sta->last_tpt) {
1797
1798                         IWL_DEBUG_RATE("LQ: SWITCHING TO NEW TABLE "
1799                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1800                                         window->success_ratio,
1801                                         window->average_tpt,
1802                                         lq_sta->last_tpt);
1803
1804                         if (!is_legacy(tbl->lq_type))
1805                                 lq_sta->enable_counter = 1;
1806
1807                         /* Swap tables; "search" becomes "active" */
1808                         lq_sta->active_tbl = active_tbl;
1809                         current_tpt = window->average_tpt;
1810
1811                 /* Else poor success; go back to mode in "active" table */
1812                 } else {
1813
1814                         IWL_DEBUG_RATE("LQ: GOING BACK TO THE OLD TABLE "
1815                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1816                                         window->success_ratio,
1817                                         window->average_tpt,
1818                                         lq_sta->last_tpt);
1819
1820                         /* Nullify "search" table */
1821                         tbl->lq_type = LQ_NONE;
1822
1823                         /* Revert to "active" table */
1824                         active_tbl = lq_sta->active_tbl;
1825                         tbl = &(lq_sta->lq_info[active_tbl]);
1826
1827                         /* Revert to "active" rate and throughput info */
1828                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1829                         current_tpt = lq_sta->last_tpt;
1830
1831                         /* Need to set up a new rate table in uCode */
1832                         update_lq = 1;
1833                 }
1834
1835                 /* Either way, we've made a decision; modulation mode
1836                  * search is done, allow rate adjustment next time. */
1837                 lq_sta->search_better_tbl = 0;
1838                 done_search = 1;        /* Don't switch modes below! */
1839                 goto lq_update;
1840         }
1841
1842         /* (Else) not in search of better modulation mode, try for better
1843          * starting rate, while staying in this mode. */
1844         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
1845                                         tbl->lq_type);
1846         low = high_low & 0xff;
1847         high = (high_low >> 8) & 0xff;
1848
1849         sr = window->success_ratio;
1850
1851         /* Collect measured throughputs for current and adjacent rates */
1852         current_tpt = window->average_tpt;
1853         if (low != IWL_RATE_INVALID)
1854                 low_tpt = tbl->win[low].average_tpt;
1855         if (high != IWL_RATE_INVALID)
1856                 high_tpt = tbl->win[high].average_tpt;
1857
1858         scale_action = 0;
1859
1860         /* Too many failures, decrease rate */
1861         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
1862                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
1863                 scale_action = -1;
1864
1865         /* No throughput measured yet for adjacent rates; try increase. */
1866         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1867                    (high_tpt == IWL_INVALID_VALUE)) {
1868
1869                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
1870                         scale_action = 1;
1871                 else if (low != IWL_RATE_INVALID)
1872                         scale_action = -1;
1873         }
1874
1875         /* Both adjacent throughputs are measured, but neither one has better
1876          * throughput; we're using the best rate, don't change it! */
1877         else if ((low_tpt != IWL_INVALID_VALUE) &&
1878                  (high_tpt != IWL_INVALID_VALUE) &&
1879                  (low_tpt < current_tpt) &&
1880                  (high_tpt < current_tpt))
1881                 scale_action = 0;
1882
1883         /* At least one adjacent rate's throughput is measured,
1884          * and may have better performance. */
1885         else {
1886                 /* Higher adjacent rate's throughput is measured */
1887                 if (high_tpt != IWL_INVALID_VALUE) {
1888                         /* Higher rate has better throughput */
1889                         if (high_tpt > current_tpt &&
1890                                         sr >= IWL_RATE_INCREASE_TH) {
1891                                 scale_action = 1;
1892                         } else {
1893                                 IWL_DEBUG_RATE
1894                                     ("decrease rate because of high tpt\n");
1895                                 scale_action = -1;
1896                         }
1897
1898                 /* Lower adjacent rate's throughput is measured */
1899                 } else if (low_tpt != IWL_INVALID_VALUE) {
1900                         /* Lower rate has better throughput */
1901                         if (low_tpt > current_tpt) {
1902                                 IWL_DEBUG_RATE
1903                                     ("decrease rate because of low tpt\n");
1904                                 scale_action = -1;
1905                         } else if (sr >= IWL_RATE_INCREASE_TH) {
1906                                 scale_action = 1;
1907                         }
1908                 }
1909         }
1910
1911         /* Sanity check; asked for decrease, but success rate or throughput
1912          * has been good at old rate.  Don't change it. */
1913         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
1914                     ((sr > IWL_RATE_HIGH_TH) ||
1915                      (current_tpt > (100 * tbl->expected_tpt[low]))))
1916                 scale_action = 0;
1917
1918         switch (scale_action) {
1919         case -1:
1920                 /* Decrease starting rate, update uCode's rate table */
1921                 if (low != IWL_RATE_INVALID) {
1922                         update_lq = 1;
1923                         index = low;
1924                 }
1925                 break;
1926         case 1:
1927                 /* Increase starting rate, update uCode's rate table */
1928                 if (high != IWL_RATE_INVALID) {
1929                         update_lq = 1;
1930                         index = high;
1931                 }
1932
1933                 break;
1934         case 0:
1935                 /* No change */
1936         default:
1937                 break;
1938         }
1939
1940         IWL_DEBUG_RATE("choose rate scale index %d action %d low %d "
1941                     "high %d type %d\n",
1942                      index, scale_action, low, high, tbl->lq_type);
1943
1944 lq_update:
1945         /* Replace uCode's rate table for the destination station. */
1946         if (update_lq) {
1947                 rate = rate_n_flags_from_tbl(tbl, index, is_green);
1948                 rs_fill_link_cmd(priv, lq_sta, rate);
1949                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1950         }
1951
1952         /* Should we stay with this modulation mode, or search for a new one? */
1953         rs_stay_in_table(lq_sta);
1954
1955         /*
1956          * Search for new modulation mode if we're:
1957          * 1)  Not changing rates right now
1958          * 2)  Not just finishing up a search
1959          * 3)  Allowing a new search
1960          */
1961         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
1962                 /* Save current throughput to compare with "search" throughput*/
1963                 lq_sta->last_tpt = current_tpt;
1964
1965                 /* Select a new "search" modulation mode to try.
1966                  * If one is found, set up the new "search" table. */
1967                 if (is_legacy(tbl->lq_type))
1968                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
1969                 else if (is_siso(tbl->lq_type))
1970                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
1971                 else
1972                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
1973
1974                 /* If new "search" mode was selected, set up in uCode table */
1975                 if (lq_sta->search_better_tbl) {
1976                         /* Access the "search" table, clear its history. */
1977                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1978                         for (i = 0; i < IWL_RATE_COUNT; i++)
1979                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1980
1981                         /* Use new "search" start rate */
1982                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1983
1984                         IWL_DEBUG_RATE("Switch current  mcs: %X index: %d\n",
1985                                      tbl->current_rate, index);
1986                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
1987                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1988                 }
1989
1990                 /* If the "active" (non-search) mode was legacy,
1991                  * and we've tried switching antennas,
1992                  * but we haven't been able to try HT modes (not available),
1993                  * stay with best antenna legacy modulation for a while
1994                  * before next round of mode comparisons. */
1995                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
1996                 if (is_legacy(tbl1->lq_type) && !conf->ht.enabled &&
1997                     lq_sta->action_counter >= 1) {
1998                         lq_sta->action_counter = 0;
1999                         IWL_DEBUG_RATE("LQ: STAY in legacy table\n");
2000                         rs_set_stay_in_table(priv, 1, lq_sta);
2001                 }
2002
2003                 /* If we're in an HT mode, and all 3 mode switch actions
2004                  * have been tried and compared, stay in this best modulation
2005                  * mode for a while before next round of mode comparisons. */
2006                 if (lq_sta->enable_counter &&
2007                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
2008                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2009                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2010                             (tid != MAX_TID_COUNT)) {
2011                                 IWL_DEBUG_RATE("try to aggregate tid %d\n", tid);
2012                                 rs_tl_turn_on_agg(priv, tid, lq_sta, sta);
2013                         }
2014                         lq_sta->action_counter = 0;
2015                         rs_set_stay_in_table(priv, 0, lq_sta);
2016                 }
2017
2018         /*
2019          * Else, don't search for a new modulation mode.
2020          * Put new timestamp in stay-in-modulation-mode flush timer if:
2021          * 1)  Not changing rates right now
2022          * 2)  Not just finishing up a search
2023          * 3)  flush timer is empty
2024          */
2025         } else {
2026                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
2027                         lq_sta->flush_timer = jiffies;
2028         }
2029
2030 out:
2031         tbl->current_rate = rate_n_flags_from_tbl(tbl, index, is_green);
2032         i = index;
2033         lq_sta->last_txrate_idx = i;
2034
2035         return;
2036 }
2037
2038
2039 static void rs_initialize_lq(struct iwl_priv *priv,
2040                              struct ieee80211_conf *conf,
2041                              struct ieee80211_sta *sta,
2042                              struct iwl_lq_sta *lq_sta)
2043 {
2044         struct iwl_scale_tbl_info *tbl;
2045         int rate_idx;
2046         int i;
2047         u32 rate;
2048         u8 use_green = rs_use_green(priv, conf);
2049         u8 active_tbl = 0;
2050         u8 valid_tx_ant;
2051
2052         if (!sta || !lq_sta)
2053                 goto out;
2054
2055         i = lq_sta->last_txrate_idx;
2056
2057         if ((lq_sta->lq.sta_id == 0xff) &&
2058             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2059                 goto out;
2060
2061         valid_tx_ant = priv->hw_params.valid_tx_ant;
2062
2063         if (!lq_sta->search_better_tbl)
2064                 active_tbl = lq_sta->active_tbl;
2065         else
2066                 active_tbl = 1 - lq_sta->active_tbl;
2067
2068         tbl = &(lq_sta->lq_info[active_tbl]);
2069
2070         if ((i < 0) || (i >= IWL_RATE_COUNT))
2071                 i = 0;
2072
2073         rate = iwl_rates[i].plcp;
2074         tbl->ant_type = first_antenna(valid_tx_ant);
2075         rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2076
2077         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2078                 rate |= RATE_MCS_CCK_MSK;
2079
2080         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2081         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2082             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2083
2084         rate = rate_n_flags_from_tbl(tbl, rate_idx, use_green);
2085         tbl->current_rate = rate;
2086         rs_set_expected_tpt_table(lq_sta, tbl);
2087         rs_fill_link_cmd(NULL, lq_sta, rate);
2088         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2089  out:
2090         return;
2091 }
2092
2093 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2094                         struct ieee80211_tx_rate_control *txrc)
2095 {
2096
2097         struct sk_buff *skb = txrc->skb;
2098         struct ieee80211_supported_band *sband = txrc->sband;
2099         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2100         struct ieee80211_conf *conf = &priv->hw->conf;
2101         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2102         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2103         struct iwl_lq_sta *lq_sta = priv_sta;
2104         int rate_idx;
2105         u64 mask_bit = 0;
2106
2107         IWL_DEBUG_RATE_LIMIT("rate scale calculate new rate for skb\n");
2108
2109         if (sta)
2110                 mask_bit = sta->supp_rates[sband->band];
2111
2112         /* Send management frames and broadcast/multicast data using lowest
2113          * rate. */
2114         if (!ieee80211_is_data(hdr->frame_control) ||
2115             is_multicast_ether_addr(hdr->addr1) || !sta || !lq_sta) {
2116                 if (!mask_bit)
2117                         info->control.rates[0].idx =
2118                                         rate_lowest_index(sband, NULL);
2119                 else
2120                         info->control.rates[0].idx =
2121                                         rate_lowest_index(sband, sta);
2122                 return;
2123         }
2124
2125         rate_idx  = lq_sta->last_txrate_idx;
2126
2127         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
2128             !lq_sta->ibss_sta_added) {
2129                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2130
2131                 if (sta_id == IWL_INVALID_STATION) {
2132                         IWL_DEBUG_RATE("LQ: ADD station %pM\n",
2133                                        hdr->addr1);
2134                         sta_id = iwl_add_station_flags(priv, hdr->addr1,
2135                                                         0, CMD_ASYNC, NULL);
2136                 }
2137                 if ((sta_id != IWL_INVALID_STATION)) {
2138                         lq_sta->lq.sta_id = sta_id;
2139                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2140                         lq_sta->ibss_sta_added = 1;
2141                         rs_initialize_lq(priv, conf, sta, lq_sta);
2142                 }
2143         }
2144
2145         if (rate_idx < 0 || rate_idx > IWL_RATE_COUNT)
2146                 rate_idx = rate_lowest_index(sband, sta);
2147         else if (sband->band == IEEE80211_BAND_5GHZ)
2148                 rate_idx -= IWL_FIRST_OFDM_RATE;
2149
2150         info->control.rates[0].idx = rate_idx;
2151 }
2152
2153 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2154                           gfp_t gfp)
2155 {
2156         struct iwl_lq_sta *lq_sta;
2157         struct iwl_priv *priv;
2158         int i, j;
2159
2160         priv = (struct iwl_priv *)priv_rate;
2161         IWL_DEBUG_RATE("create station rate scale window\n");
2162
2163         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2164
2165         if (lq_sta == NULL)
2166                 return NULL;
2167         lq_sta->lq.sta_id = 0xff;
2168
2169
2170         for (j = 0; j < LQ_SIZE; j++)
2171                 for (i = 0; i < IWL_RATE_COUNT; i++)
2172                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2173
2174         return lq_sta;
2175 }
2176
2177 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2178                          struct ieee80211_sta *sta, void *priv_sta)
2179 {
2180         int i, j;
2181         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2182         struct ieee80211_conf *conf = &priv->hw->conf;
2183         struct iwl_lq_sta *lq_sta = priv_sta;
2184         u16 mask_bit = 0;
2185
2186         lq_sta->flush_timer = 0;
2187         lq_sta->supp_rates = sta->supp_rates[sband->band];
2188         for (j = 0; j < LQ_SIZE; j++)
2189                 for (i = 0; i < IWL_RATE_COUNT; i++)
2190                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2191
2192         IWL_DEBUG_RATE("LQ: *** rate scale station global init ***\n");
2193         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2194          * the lowest or the highest rate.. Could consider using RSSI from
2195          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2196          * after assoc.. */
2197
2198         lq_sta->ibss_sta_added = 0;
2199         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2200                 u8 sta_id = iwl_find_station(priv, sta->addr);
2201
2202                 /* for IBSS the call are from tasklet */
2203                 IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2204
2205                 if (sta_id == IWL_INVALID_STATION) {
2206                         IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2207                         sta_id = iwl_add_station_flags(priv, sta->addr,
2208                                                         0, CMD_ASYNC, NULL);
2209                 }
2210                 if ((sta_id != IWL_INVALID_STATION)) {
2211                         lq_sta->lq.sta_id = sta_id;
2212                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2213                 }
2214                 /* FIXME: this is w/a remove it later */
2215                 priv->assoc_station_added = 1;
2216         }
2217
2218         lq_sta->is_dup = 0;
2219         lq_sta->is_green = rs_use_green(priv, conf);
2220         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2221         lq_sta->active_rate_basic = priv->active_rate_basic;
2222         lq_sta->band = priv->band;
2223         /*
2224          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2225          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2226          */
2227         lq_sta->active_siso_rate = sta->ht_cap.mcs.rx_mask[0] << 1;
2228         lq_sta->active_siso_rate |= sta->ht_cap.mcs.rx_mask[0] & 0x1;
2229         lq_sta->active_siso_rate &= ~((u16)0x2);
2230         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2231
2232         /* Same here */
2233         lq_sta->active_mimo2_rate = sta->ht_cap.mcs.rx_mask[1] << 1;
2234         lq_sta->active_mimo2_rate |= sta->ht_cap.mcs.rx_mask[1] & 0x1;
2235         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2236         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2237
2238         lq_sta->active_mimo3_rate = sta->ht_cap.mcs.rx_mask[2] << 1;
2239         lq_sta->active_mimo3_rate |= sta->ht_cap.mcs.rx_mask[2] & 0x1;
2240         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2241         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2242
2243         IWL_DEBUG_RATE("SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2244                      lq_sta->active_siso_rate,
2245                      lq_sta->active_mimo2_rate,
2246                      lq_sta->active_mimo3_rate);
2247
2248         /* These values will be overridden later */
2249         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2250         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2251
2252         /* as default allow aggregation for all tids */
2253         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2254         lq_sta->drv = priv;
2255
2256         /* Find highest tx rate supported by hardware and destination station */
2257         mask_bit = sta->supp_rates[sband->band] & lq_sta->active_legacy_rate;
2258         lq_sta->last_txrate_idx = 3;
2259         for (i = 0; i < sband->n_bitrates; i++)
2260                 if (mask_bit & BIT(i))
2261                         lq_sta->last_txrate_idx = i;
2262
2263         /* For MODE_IEEE80211A, skip over cck rates in global rate table */
2264         if (sband->band == IEEE80211_BAND_5GHZ)
2265                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2266
2267         rs_initialize_lq(priv, conf, sta, lq_sta);
2268 }
2269
2270 static void rs_fill_link_cmd(const struct iwl_priv *priv,
2271                              struct iwl_lq_sta *lq_sta, u32 new_rate)
2272 {
2273         struct iwl_scale_tbl_info tbl_type;
2274         int index = 0;
2275         int rate_idx;
2276         int repeat_rate = 0;
2277         u8 ant_toggle_cnt = 0;
2278         u8 use_ht_possible = 1;
2279         u8 valid_tx_ant = 0;
2280         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2281
2282         /* Override starting rate (index 0) if needed for debug purposes */
2283         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2284
2285         /* Interpret new_rate (rate_n_flags) */
2286         memset(&tbl_type, 0, sizeof(tbl_type));
2287         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2288                                   &tbl_type, &rate_idx);
2289
2290         /* How many times should we repeat the initial rate? */
2291         if (is_legacy(tbl_type.lq_type)) {
2292                 ant_toggle_cnt = 1;
2293                 repeat_rate = IWL_NUMBER_TRY;
2294         } else {
2295                 repeat_rate = IWL_HT_NUMBER_TRY;
2296         }
2297
2298         lq_cmd->general_params.mimo_delimiter =
2299                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2300
2301         /* Fill 1st table entry (index 0) */
2302         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2303
2304         if (num_of_ant(tbl_type.ant_type) == 1) {
2305                 lq_cmd->general_params.single_stream_ant_msk =
2306                                                 tbl_type.ant_type;
2307         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2308                 lq_cmd->general_params.dual_stream_ant_msk =
2309                                                 tbl_type.ant_type;
2310         } /* otherwise we don't modify the existing value */
2311
2312         index++;
2313         repeat_rate--;
2314
2315         if (priv)
2316                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2317
2318         /* Fill rest of rate table */
2319         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2320                 /* Repeat initial/next rate.
2321                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2322                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2323                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2324                         if (is_legacy(tbl_type.lq_type)) {
2325                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2326                                         ant_toggle_cnt++;
2327                                 else if (priv &&
2328                                          rs_toggle_antenna(valid_tx_ant,
2329                                                         &new_rate, &tbl_type))
2330                                         ant_toggle_cnt = 1;
2331 }
2332
2333                         /* Override next rate if needed for debug purposes */
2334                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2335
2336                         /* Fill next table entry */
2337                         lq_cmd->rs_table[index].rate_n_flags =
2338                                         cpu_to_le32(new_rate);
2339                         repeat_rate--;
2340                         index++;
2341                 }
2342
2343                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2344                                                 &rate_idx);
2345
2346                 /* Indicate to uCode which entries might be MIMO.
2347                  * If initial rate was MIMO, this will finally end up
2348                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2349                 if (is_mimo(tbl_type.lq_type))
2350                         lq_cmd->general_params.mimo_delimiter = index;
2351
2352                 /* Get next rate */
2353                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2354                                              use_ht_possible);
2355
2356                 /* How many times should we repeat the next rate? */
2357                 if (is_legacy(tbl_type.lq_type)) {
2358                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2359                                 ant_toggle_cnt++;
2360                         else if (priv &&
2361                                  rs_toggle_antenna(valid_tx_ant,
2362                                                    &new_rate, &tbl_type))
2363                                 ant_toggle_cnt = 1;
2364
2365                         repeat_rate = IWL_NUMBER_TRY;
2366                 } else {
2367                         repeat_rate = IWL_HT_NUMBER_TRY;
2368                 }
2369
2370                 /* Don't allow HT rates after next pass.
2371                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2372                 use_ht_possible = 0;
2373
2374                 /* Override next rate if needed for debug purposes */
2375                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2376
2377                 /* Fill next table entry */
2378                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2379
2380                 index++;
2381                 repeat_rate--;
2382         }
2383
2384         lq_cmd->agg_params.agg_frame_cnt_limit = 64;
2385         lq_cmd->agg_params.agg_dis_start_th = 3;
2386         lq_cmd->agg_params.agg_time_limit = cpu_to_le16(4000);
2387 }
2388
2389 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2390 {
2391         return hw->priv;
2392 }
2393 /* rate scale requires free function to be implemented */
2394 static void rs_free(void *priv_rate)
2395 {
2396         return;
2397 }
2398
2399 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2400                         void *priv_sta)
2401 {
2402         struct iwl_lq_sta *lq_sta = priv_sta;
2403         struct iwl_priv *priv __maybe_unused = priv_r;
2404
2405         IWL_DEBUG_RATE("enter\n");
2406         kfree(lq_sta);
2407         IWL_DEBUG_RATE("leave\n");
2408 }
2409
2410
2411 #ifdef CONFIG_MAC80211_DEBUGFS
2412 static int open_file_generic(struct inode *inode, struct file *file)
2413 {
2414         file->private_data = inode->i_private;
2415         return 0;
2416 }
2417 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2418                              u32 *rate_n_flags, int index)
2419 {
2420         struct iwl_priv *priv;
2421
2422         priv = lq_sta->drv;
2423         if (lq_sta->dbg_fixed_rate) {
2424                 if (index < 12) {
2425                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2426                 } else {
2427                         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2428                                 *rate_n_flags = 0x800D;
2429                         else
2430                                 *rate_n_flags = 0x820A;
2431                 }
2432                 IWL_DEBUG_RATE("Fixed rate ON\n");
2433         } else {
2434                 IWL_DEBUG_RATE("Fixed rate OFF\n");
2435         }
2436 }
2437
2438 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2439                         const char __user *user_buf, size_t count, loff_t *ppos)
2440 {
2441         struct iwl_lq_sta *lq_sta = file->private_data;
2442         struct iwl_priv *priv;
2443         char buf[64];
2444         int buf_size;
2445         u32 parsed_rate;
2446
2447         priv = lq_sta->drv;
2448         memset(buf, 0, sizeof(buf));
2449         buf_size = min(count, sizeof(buf) -  1);
2450         if (copy_from_user(buf, user_buf, buf_size))
2451                 return -EFAULT;
2452
2453         if (sscanf(buf, "%x", &parsed_rate) == 1)
2454                 lq_sta->dbg_fixed_rate = parsed_rate;
2455         else
2456                 lq_sta->dbg_fixed_rate = 0;
2457
2458         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2459         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2460         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2461         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2462
2463         IWL_DEBUG_RATE("sta_id %d rate 0x%X\n",
2464                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2465
2466         if (lq_sta->dbg_fixed_rate) {
2467                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2468                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2469         }
2470
2471         return count;
2472 }
2473
2474 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2475                         char __user *user_buf, size_t count, loff_t *ppos)
2476 {
2477         char buff[1024];
2478         int desc = 0;
2479         int i = 0;
2480
2481         struct iwl_lq_sta *lq_sta = file->private_data;
2482
2483         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2484         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2485                         lq_sta->total_failed, lq_sta->total_success,
2486                         lq_sta->active_legacy_rate);
2487         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2488                         lq_sta->dbg_fixed_rate);
2489         desc += sprintf(buff+desc, "general:"
2490                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2491                 lq_sta->lq.general_params.flags,
2492                 lq_sta->lq.general_params.mimo_delimiter,
2493                 lq_sta->lq.general_params.single_stream_ant_msk,
2494                 lq_sta->lq.general_params.dual_stream_ant_msk);
2495
2496         desc += sprintf(buff+desc, "agg:"
2497                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2498                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2499                         lq_sta->lq.agg_params.agg_dis_start_th,
2500                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2501
2502         desc += sprintf(buff+desc,
2503                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2504                         lq_sta->lq.general_params.start_rate_index[0],
2505                         lq_sta->lq.general_params.start_rate_index[1],
2506                         lq_sta->lq.general_params.start_rate_index[2],
2507                         lq_sta->lq.general_params.start_rate_index[3]);
2508
2509
2510         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2511                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2512                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2513
2514         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2515 }
2516
2517 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2518         .write = rs_sta_dbgfs_scale_table_write,
2519         .read = rs_sta_dbgfs_scale_table_read,
2520         .open = open_file_generic,
2521 };
2522 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2523                         char __user *user_buf, size_t count, loff_t *ppos)
2524 {
2525         char buff[1024];
2526         int desc = 0;
2527         int i, j;
2528
2529         struct iwl_lq_sta *lq_sta = file->private_data;
2530         for (i = 0; i < LQ_SIZE; i++) {
2531                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2532                                 "rate=0x%X\n",
2533                                 lq_sta->active_tbl == i ? "*" : "x",
2534                                 lq_sta->lq_info[i].lq_type,
2535                                 lq_sta->lq_info[i].is_SGI,
2536                                 lq_sta->lq_info[i].is_fat,
2537                                 lq_sta->lq_info[i].is_dup,
2538                                 lq_sta->lq_info[i].current_rate);
2539                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2540                         desc += sprintf(buff+desc,
2541                                 "counter=%d success=%d %%=%d\n",
2542                                 lq_sta->lq_info[i].win[j].counter,
2543                                 lq_sta->lq_info[i].win[j].success_counter,
2544                                 lq_sta->lq_info[i].win[j].success_ratio);
2545                 }
2546         }
2547         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2548 }
2549
2550 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2551         .read = rs_sta_dbgfs_stats_table_read,
2552         .open = open_file_generic,
2553 };
2554
2555 static void rs_add_debugfs(void *priv, void *priv_sta,
2556                                         struct dentry *dir)
2557 {
2558         struct iwl_lq_sta *lq_sta = priv_sta;
2559         lq_sta->rs_sta_dbgfs_scale_table_file =
2560                 debugfs_create_file("rate_scale_table", 0600, dir,
2561                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2562         lq_sta->rs_sta_dbgfs_stats_table_file =
2563                 debugfs_create_file("rate_stats_table", 0600, dir,
2564                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2565         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2566                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2567                 &lq_sta->tx_agg_tid_en);
2568
2569 }
2570
2571 static void rs_remove_debugfs(void *priv, void *priv_sta)
2572 {
2573         struct iwl_lq_sta *lq_sta = priv_sta;
2574         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2575         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2576         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2577 }
2578 #endif
2579
2580 static struct rate_control_ops rs_ops = {
2581         .module = NULL,
2582         .name = RS_NAME,
2583         .tx_status = rs_tx_status,
2584         .get_rate = rs_get_rate,
2585         .rate_init = rs_rate_init,
2586         .alloc = rs_alloc,
2587         .free = rs_free,
2588         .alloc_sta = rs_alloc_sta,
2589         .free_sta = rs_free_sta,
2590 #ifdef CONFIG_MAC80211_DEBUGFS
2591         .add_sta_debugfs = rs_add_debugfs,
2592         .remove_sta_debugfs = rs_remove_debugfs,
2593 #endif
2594 };
2595
2596 int iwlagn_rate_control_register(void)
2597 {
2598         return ieee80211_rate_control_register(&rs_ops);
2599 }
2600
2601 void iwlagn_rate_control_unregister(void)
2602 {
2603         ieee80211_rate_control_unregister(&rs_ops);
2604 }
2605