e10e0ca09ce9f3f6f4e01aa1e89a7ece273b90ca
[linux-2.6.git] / drivers / net / wireless / iwlwifi / iwl-agn-rs.c
1 /******************************************************************************
2  *
3  * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
17  *
18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  * Contact Information:
22  * James P. Ketrenos <ipw2100-admin@linux.intel.com>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  *****************************************************************************/
26 #include <linux/kernel.h>
27 #include <linux/init.h>
28 #include <linux/skbuff.h>
29 #include <linux/wireless.h>
30 #include <net/mac80211.h>
31
32 #include <linux/netdevice.h>
33 #include <linux/etherdevice.h>
34 #include <linux/delay.h>
35
36 #include <linux/workqueue.h>
37
38 #include "iwl-dev.h"
39 #include "iwl-sta.h"
40 #include "iwl-core.h"
41 #include "iwl-helpers.h"
42
43 #define RS_NAME "iwl-agn-rs"
44
45 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
46 #define IWL_NUMBER_TRY      1
47 #define IWL_HT_NUMBER_TRY   3
48
49 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
50 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
51 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
52
53 /* max time to accum history 2 seconds */
54 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
55
56 static u8 rs_ht_to_legacy[] = {
57         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
59         IWL_RATE_6M_INDEX,
60         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
61         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
62         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
63         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
64 };
65
66 static const u8 ant_toggle_lookup[] = {
67         /*ANT_NONE -> */ ANT_NONE,
68         /*ANT_A    -> */ ANT_B,
69         /*ANT_B    -> */ ANT_C,
70         /*ANT_AB   -> */ ANT_BC,
71         /*ANT_C    -> */ ANT_A,
72         /*ANT_AC   -> */ ANT_AB,
73         /*ANT_BC   -> */ ANT_AC,
74         /*ANT_ABC  -> */ ANT_ABC,
75 };
76
77 /**
78  * struct iwl_rate_scale_data -- tx success history for one rate
79  */
80 struct iwl_rate_scale_data {
81         u64 data;               /* bitmap of successful frames */
82         s32 success_counter;    /* number of frames successful */
83         s32 success_ratio;      /* per-cent * 128  */
84         s32 counter;            /* number of frames attempted */
85         s32 average_tpt;        /* success ratio * expected throughput */
86         unsigned long stamp;
87 };
88
89 /**
90  * struct iwl_scale_tbl_info -- tx params and success history for all rates
91  *
92  * There are two of these in struct iwl_lq_sta,
93  * one for "active", and one for "search".
94  */
95 struct iwl_scale_tbl_info {
96         enum iwl_table_type lq_type;
97         u8 ant_type;
98         u8 is_SGI;      /* 1 = short guard interval */
99         u8 is_fat;      /* 1 = 40 MHz channel width */
100         u8 is_dup;      /* 1 = duplicated data streams */
101         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
102         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
103         u32 current_rate;  /* rate_n_flags, uCode API format */
104         struct iwl_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
105 };
106
107 struct iwl_traffic_load {
108         unsigned long time_stamp;       /* age of the oldest statistics */
109         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
110                                                  * slice */
111         u32 total;                      /* total num of packets during the
112                                          * last TID_MAX_TIME_DIFF */
113         u8 queue_count;                 /* number of queues that has
114                                          * been used since the last cleanup */
115         u8 head;                        /* start of the circular buffer */
116 };
117
118 /**
119  * struct iwl_lq_sta -- driver's rate scaling private structure
120  *
121  * Pointer to this gets passed back and forth between driver and mac80211.
122  */
123 struct iwl_lq_sta {
124         u8 active_tbl;          /* index of active table, range 0-1 */
125         u8 enable_counter;      /* indicates HT mode */
126         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
127         u8 search_better_tbl;   /* 1: currently trying alternate mode */
128         s32 last_tpt;
129
130         /* The following determine when to search for a new mode */
131         u32 table_count_limit;
132         u32 max_failure_limit;  /* # failed frames before new search */
133         u32 max_success_limit;  /* # successful frames before new search */
134         u32 table_count;
135         u32 total_failed;       /* total failed frames, any/all rates */
136         u32 total_success;      /* total successful frames, any/all rates */
137         u32 flush_timer;        /* time staying in mode before new search */
138
139         u8 action_counter;      /* # mode-switch actions tried */
140         u8 is_green;
141         u8 is_dup;
142         enum ieee80211_band band;
143         u8 ibss_sta_added;
144
145         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
146         u32 supp_rates;
147         u16 active_legacy_rate;
148         u16 active_siso_rate;
149         u16 active_mimo2_rate;
150         u16 active_mimo3_rate;
151         u16 active_rate_basic;
152
153         struct iwl_link_quality_cmd lq;
154         struct iwl_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
155         struct iwl_traffic_load load[TID_MAX_LOAD_COUNT];
156         u8 tx_agg_tid_en;
157 #ifdef CONFIG_MAC80211_DEBUGFS
158         struct dentry *rs_sta_dbgfs_scale_table_file;
159         struct dentry *rs_sta_dbgfs_stats_table_file;
160         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
161         u32 dbg_fixed_rate;
162 #endif
163         struct iwl_priv *drv;
164
165         /* used to be in sta_info */
166         int last_txrate_idx;
167 };
168
169 static void rs_rate_scale_perform(struct iwl_priv *priv,
170                                    struct ieee80211_hdr *hdr,
171                                    struct ieee80211_sta *sta,
172                                    struct iwl_lq_sta *lq_sta);
173 static void rs_fill_link_cmd(const struct iwl_priv *priv,
174                              struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
175
176
177 #ifdef CONFIG_MAC80211_DEBUGFS
178 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
179                              u32 *rate_n_flags, int index);
180 #else
181 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
182                              u32 *rate_n_flags, int index)
183 {}
184 #endif
185
186 /*
187  * Expected throughput metrics for following rates:
188  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
189  * "G" is the only table that supports CCK (the first 4 rates).
190  */
191 /*FIXME:RS:need to spearate tables for MIMO2/MIMO3*/
192 static s32 expected_tpt_A[IWL_RATE_COUNT] = {
193         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186, 186
194 };
195
196 static s32 expected_tpt_G[IWL_RATE_COUNT] = {
197         7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 186
198 };
199
200 static s32 expected_tpt_siso20MHz[IWL_RATE_COUNT] = {
201         0, 0, 0, 0, 42, 42, 76, 102, 124, 159, 183, 193, 202
202 };
203
204 static s32 expected_tpt_siso20MHzSGI[IWL_RATE_COUNT] = {
205         0, 0, 0, 0, 46, 46, 82, 110, 132, 168, 192, 202, 211
206 };
207
208 static s32 expected_tpt_mimo20MHz[IWL_RATE_COUNT] = {
209         0, 0, 0, 0, 74, 74, 123, 155, 179, 214, 236, 244, 251
210 };
211
212 static s32 expected_tpt_mimo20MHzSGI[IWL_RATE_COUNT] = {
213         0, 0, 0, 0, 81, 81, 131, 164, 188, 222, 243, 251, 257
214 };
215
216 static s32 expected_tpt_siso40MHz[IWL_RATE_COUNT] = {
217         0, 0, 0, 0, 77, 77, 127, 160, 184, 220, 242, 250, 257
218 };
219
220 static s32 expected_tpt_siso40MHzSGI[IWL_RATE_COUNT] = {
221         0, 0, 0, 0, 83, 83, 135, 169, 193, 229, 250, 257, 264
222 };
223
224 static s32 expected_tpt_mimo40MHz[IWL_RATE_COUNT] = {
225         0, 0, 0, 0, 123, 123, 182, 214, 235, 264, 279, 285, 289
226 };
227
228 static s32 expected_tpt_mimo40MHzSGI[IWL_RATE_COUNT] = {
229         0, 0, 0, 0, 131, 131, 191, 222, 242, 270, 284, 289, 293
230 };
231
232 static inline u8 rs_extract_rate(u32 rate_n_flags)
233 {
234         return (u8)(rate_n_flags & 0xFF);
235 }
236
237 static void rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
238 {
239         window->data = 0;
240         window->success_counter = 0;
241         window->success_ratio = IWL_INVALID_VALUE;
242         window->counter = 0;
243         window->average_tpt = IWL_INVALID_VALUE;
244         window->stamp = 0;
245 }
246
247 static inline u8 rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
248 {
249         return (ant_type & valid_antenna) == ant_type;
250 }
251
252 /*
253  *      removes the old data from the statistics. All data that is older than
254  *      TID_MAX_TIME_DIFF, will be deleted.
255  */
256 static void rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
257 {
258         /* The oldest age we want to keep */
259         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
260
261         while (tl->queue_count &&
262                (tl->time_stamp < oldest_time)) {
263                 tl->total -= tl->packet_count[tl->head];
264                 tl->packet_count[tl->head] = 0;
265                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
266                 tl->queue_count--;
267                 tl->head++;
268                 if (tl->head >= TID_QUEUE_MAX_SIZE)
269                         tl->head = 0;
270         }
271 }
272
273 /*
274  *      increment traffic load value for tid and also remove
275  *      any old values if passed the certain time period
276  */
277 static u8 rs_tl_add_packet(struct iwl_lq_sta *lq_data,
278                            struct ieee80211_hdr *hdr)
279 {
280         u32 curr_time = jiffies_to_msecs(jiffies);
281         u32 time_diff;
282         s32 index;
283         struct iwl_traffic_load *tl = NULL;
284         __le16 fc = hdr->frame_control;
285         u8 tid;
286
287         if (ieee80211_is_data_qos(fc)) {
288                 u8 *qc = ieee80211_get_qos_ctl(hdr);
289                 tid = qc[0] & 0xf;
290         } else
291                 return MAX_TID_COUNT;
292
293         tl = &lq_data->load[tid];
294
295         curr_time -= curr_time % TID_ROUND_VALUE;
296
297         /* Happens only for the first packet. Initialize the data */
298         if (!(tl->queue_count)) {
299                 tl->total = 1;
300                 tl->time_stamp = curr_time;
301                 tl->queue_count = 1;
302                 tl->head = 0;
303                 tl->packet_count[0] = 1;
304                 return MAX_TID_COUNT;
305         }
306
307         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
308         index = time_diff / TID_QUEUE_CELL_SPACING;
309
310         /* The history is too long: remove data that is older than */
311         /* TID_MAX_TIME_DIFF */
312         if (index >= TID_QUEUE_MAX_SIZE)
313                 rs_tl_rm_old_stats(tl, curr_time);
314
315         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
316         tl->packet_count[index] = tl->packet_count[index] + 1;
317         tl->total = tl->total + 1;
318
319         if ((index + 1) > tl->queue_count)
320                 tl->queue_count = index + 1;
321
322         return tid;
323 }
324
325 /*
326         get the traffic load value for tid
327 */
328 static u32 rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
329 {
330         u32 curr_time = jiffies_to_msecs(jiffies);
331         u32 time_diff;
332         s32 index;
333         struct iwl_traffic_load *tl = NULL;
334
335         if (tid >= TID_MAX_LOAD_COUNT)
336                 return 0;
337
338         tl = &(lq_data->load[tid]);
339
340         curr_time -= curr_time % TID_ROUND_VALUE;
341
342         if (!(tl->queue_count))
343                 return 0;
344
345         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
346         index = time_diff / TID_QUEUE_CELL_SPACING;
347
348         /* The history is too long: remove data that is older than */
349         /* TID_MAX_TIME_DIFF */
350         if (index >= TID_QUEUE_MAX_SIZE)
351                 rs_tl_rm_old_stats(tl, curr_time);
352
353         return tl->total;
354 }
355
356 static void rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
357                                       struct iwl_lq_sta *lq_data, u8 tid,
358                                       struct ieee80211_sta *sta)
359 {
360         if (rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
361                 IWL_DEBUG_HT("Starting Tx agg: STA: %pM tid: %d\n",
362                                 sta->addr, tid);
363                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
364         }
365 }
366
367 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
368                               struct iwl_lq_sta *lq_data,
369                               struct ieee80211_sta *sta)
370 {
371         if ((tid < TID_MAX_LOAD_COUNT))
372                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
373         else if (tid == IWL_AGG_ALL_TID)
374                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
375                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
376 }
377
378 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
379 {
380         return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
381                !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
382                !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
383 }
384
385 /**
386  * rs_collect_tx_data - Update the success/failure sliding window
387  *
388  * We keep a sliding window of the last 62 packets transmitted
389  * at this rate.  window->data contains the bitmask of successful
390  * packets.
391  */
392 static int rs_collect_tx_data(struct iwl_rate_scale_data *windows,
393                               int scale_index, s32 tpt, int retries,
394                               int successes)
395 {
396         struct iwl_rate_scale_data *window = NULL;
397         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
398         s32 fail_count;
399
400         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
401                 return -EINVAL;
402
403         /* Select data for current tx bit rate */
404         window = &(windows[scale_index]);
405
406         /*
407          * Keep track of only the latest 62 tx frame attempts in this rate's
408          * history window; anything older isn't really relevant any more.
409          * If we have filled up the sliding window, drop the oldest attempt;
410          * if the oldest attempt (highest bit in bitmap) shows "success",
411          * subtract "1" from the success counter (this is the main reason
412          * we keep these bitmaps!).
413          */
414         while (retries > 0) {
415                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
416
417                         /* remove earliest */
418                         window->counter = IWL_RATE_MAX_WINDOW - 1;
419
420                         if (window->data & mask) {
421                                 window->data &= ~mask;
422                                 window->success_counter--;
423                         }
424                 }
425
426                 /* Increment frames-attempted counter */
427                 window->counter++;
428
429                 /* Shift bitmap by one frame (throw away oldest history),
430                  * OR in "1", and increment "success" if this
431                  * frame was successful. */
432                 window->data <<= 1;
433                 if (successes > 0) {
434                         window->success_counter++;
435                         window->data |= 0x1;
436                         successes--;
437                 }
438
439                 retries--;
440         }
441
442         /* Calculate current success ratio, avoid divide-by-0! */
443         if (window->counter > 0)
444                 window->success_ratio = 128 * (100 * window->success_counter)
445                                         / window->counter;
446         else
447                 window->success_ratio = IWL_INVALID_VALUE;
448
449         fail_count = window->counter - window->success_counter;
450
451         /* Calculate average throughput, if we have enough history. */
452         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
453             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
454                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
455         else
456                 window->average_tpt = IWL_INVALID_VALUE;
457
458         /* Tag this window as having been updated */
459         window->stamp = jiffies;
460
461         return 0;
462 }
463
464 /*
465  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
466  */
467 /* FIXME:RS:remove this function and put the flags statically in the table */
468 static u32 rate_n_flags_from_tbl(struct iwl_scale_tbl_info *tbl,
469                                        int index, u8 use_green)
470 {
471         u32 rate_n_flags = 0;
472
473         if (is_legacy(tbl->lq_type)) {
474                 rate_n_flags = iwl_rates[index].plcp;
475                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
476                         rate_n_flags |= RATE_MCS_CCK_MSK;
477
478         } else if (is_Ht(tbl->lq_type)) {
479                 if (index > IWL_LAST_OFDM_RATE) {
480                         IWL_ERROR("invalid HT rate index %d\n", index);
481                         index = IWL_LAST_OFDM_RATE;
482                 }
483                 rate_n_flags = RATE_MCS_HT_MSK;
484
485                 if (is_siso(tbl->lq_type))
486                         rate_n_flags |= iwl_rates[index].plcp_siso;
487                 else if (is_mimo2(tbl->lq_type))
488                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
489                 else
490                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
491         } else {
492                 IWL_ERROR("Invalid tbl->lq_type %d\n", tbl->lq_type);
493         }
494
495         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
496                                                      RATE_MCS_ANT_ABC_MSK);
497
498         if (is_Ht(tbl->lq_type)) {
499                 if (tbl->is_fat) {
500                         if (tbl->is_dup)
501                                 rate_n_flags |= RATE_MCS_DUP_MSK;
502                         else
503                                 rate_n_flags |= RATE_MCS_FAT_MSK;
504                 }
505                 if (tbl->is_SGI)
506                         rate_n_flags |= RATE_MCS_SGI_MSK;
507
508                 if (use_green) {
509                         rate_n_flags |= RATE_MCS_GF_MSK;
510                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
511                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
512                                 IWL_ERROR("GF was set with SGI:SISO\n");
513                         }
514                 }
515         }
516         return rate_n_flags;
517 }
518
519 /*
520  * Interpret uCode API's rate_n_flags format,
521  * fill "search" or "active" tx mode table.
522  */
523 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
524                                     enum ieee80211_band band,
525                                     struct iwl_scale_tbl_info *tbl,
526                                     int *rate_idx)
527 {
528         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
529         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
530         u8 mcs;
531
532         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
533
534         if (*rate_idx  == IWL_RATE_INVALID) {
535                 *rate_idx = -1;
536                 return -EINVAL;
537         }
538         tbl->is_SGI = 0;        /* default legacy setup */
539         tbl->is_fat = 0;
540         tbl->is_dup = 0;
541         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
542         tbl->lq_type = LQ_NONE;
543
544         /* legacy rate format */
545         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
546                 if (num_of_ant == 1) {
547                         if (band == IEEE80211_BAND_5GHZ)
548                                 tbl->lq_type = LQ_A;
549                         else
550                                 tbl->lq_type = LQ_G;
551                 }
552         /* HT rate format */
553         } else {
554                 if (rate_n_flags & RATE_MCS_SGI_MSK)
555                         tbl->is_SGI = 1;
556
557                 if ((rate_n_flags & RATE_MCS_FAT_MSK) ||
558                     (rate_n_flags & RATE_MCS_DUP_MSK))
559                         tbl->is_fat = 1;
560
561                 if (rate_n_flags & RATE_MCS_DUP_MSK)
562                         tbl->is_dup = 1;
563
564                 mcs = rs_extract_rate(rate_n_flags);
565
566                 /* SISO */
567                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
568                         if (num_of_ant == 1)
569                                 tbl->lq_type = LQ_SISO; /*else NONE*/
570                 /* MIMO2 */
571                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
572                         if (num_of_ant == 2)
573                                 tbl->lq_type = LQ_MIMO2;
574                 /* MIMO3 */
575                 } else {
576                         if (num_of_ant == 3)
577                                 tbl->lq_type = LQ_MIMO3;
578                 }
579         }
580         return 0;
581 }
582
583 /* switch to another antenna/antennas and return 1 */
584 /* if no other valid antenna found, return 0 */
585 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
586                              struct iwl_scale_tbl_info *tbl)
587 {
588         u8 new_ant_type;
589
590         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
591                 return 0;
592
593         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
594                 return 0;
595
596         new_ant_type = ant_toggle_lookup[tbl->ant_type];
597
598         while ((new_ant_type != tbl->ant_type) &&
599                !rs_is_valid_ant(valid_ant, new_ant_type))
600                 new_ant_type = ant_toggle_lookup[new_ant_type];
601
602         if (new_ant_type == tbl->ant_type)
603                 return 0;
604
605         tbl->ant_type = new_ant_type;
606         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
607         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
608         return 1;
609 }
610
611 /* FIXME:RS: in 4965 we don't use greenfield at all */
612 /* FIXME:RS: don't use greenfield for now in TX */
613 #if 0
614 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
615 {
616         return (conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
617                 priv->current_ht_config.is_green_field &&
618                 !priv->current_ht_config.non_GF_STA_present;
619 }
620 #endif
621 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
622 {
623         return 0;
624 }
625
626 /**
627  * rs_get_supported_rates - get the available rates
628  *
629  * if management frame or broadcast frame only return
630  * basic available rates.
631  *
632  */
633 static u16 rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
634                                   struct ieee80211_hdr *hdr,
635                                   enum iwl_table_type rate_type)
636 {
637         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
638             lq_sta->active_rate_basic)
639                 return lq_sta->active_rate_basic;
640
641         if (is_legacy(rate_type)) {
642                 return lq_sta->active_legacy_rate;
643         } else {
644                 if (is_siso(rate_type))
645                         return lq_sta->active_siso_rate;
646                 else if (is_mimo2(rate_type))
647                         return lq_sta->active_mimo2_rate;
648                 else
649                         return lq_sta->active_mimo3_rate;
650         }
651 }
652
653 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
654                                 int rate_type)
655 {
656         u8 high = IWL_RATE_INVALID;
657         u8 low = IWL_RATE_INVALID;
658
659         /* 802.11A or ht walks to the next literal adjacent rate in
660          * the rate table */
661         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
662                 int i;
663                 u32 mask;
664
665                 /* Find the previous rate that is in the rate mask */
666                 i = index - 1;
667                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
668                         if (rate_mask & mask) {
669                                 low = i;
670                                 break;
671                         }
672                 }
673
674                 /* Find the next rate that is in the rate mask */
675                 i = index + 1;
676                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
677                         if (rate_mask & mask) {
678                                 high = i;
679                                 break;
680                         }
681                 }
682
683                 return (high << 8) | low;
684         }
685
686         low = index;
687         while (low != IWL_RATE_INVALID) {
688                 low = iwl_rates[low].prev_rs;
689                 if (low == IWL_RATE_INVALID)
690                         break;
691                 if (rate_mask & (1 << low))
692                         break;
693                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
694         }
695
696         high = index;
697         while (high != IWL_RATE_INVALID) {
698                 high = iwl_rates[high].next_rs;
699                 if (high == IWL_RATE_INVALID)
700                         break;
701                 if (rate_mask & (1 << high))
702                         break;
703                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
704         }
705
706         return (high << 8) | low;
707 }
708
709 static u32 rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
710                              struct iwl_scale_tbl_info *tbl,
711                              u8 scale_index, u8 ht_possible)
712 {
713         s32 low;
714         u16 rate_mask;
715         u16 high_low;
716         u8 switch_to_legacy = 0;
717         u8 is_green = lq_sta->is_green;
718
719         /* check if we need to switch from HT to legacy rates.
720          * assumption is that mandatory rates (1Mbps or 6Mbps)
721          * are always supported (spec demand) */
722         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
723                 switch_to_legacy = 1;
724                 scale_index = rs_ht_to_legacy[scale_index];
725                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
726                         tbl->lq_type = LQ_A;
727                 else
728                         tbl->lq_type = LQ_G;
729
730                 if (num_of_ant(tbl->ant_type) > 1)
731                         tbl->ant_type = ANT_A;/*FIXME:RS*/
732
733                 tbl->is_fat = 0;
734                 tbl->is_SGI = 0;
735         }
736
737         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
738
739         /* Mask with station rate restriction */
740         if (is_legacy(tbl->lq_type)) {
741                 /* supp_rates has no CCK bits in A mode */
742                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
743                         rate_mask  = (u16)(rate_mask &
744                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
745                 else
746                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
747         }
748
749         /* If we switched from HT to legacy, check current rate */
750         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
751                 low = scale_index;
752                 goto out;
753         }
754
755         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
756                                         tbl->lq_type);
757         low = high_low & 0xff;
758
759         if (low == IWL_RATE_INVALID)
760                 low = scale_index;
761
762 out:
763         return rate_n_flags_from_tbl(tbl, low, is_green);
764 }
765
766 /*
767  * mac80211 sends us Tx status
768  */
769 static void rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
770                          struct ieee80211_sta *sta, void *priv_sta,
771                          struct sk_buff *skb)
772 {
773         int status;
774         u8 retries;
775         int rs_index, index = 0;
776         struct iwl_lq_sta *lq_sta;
777         struct iwl_link_quality_cmd *table;
778         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
779         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
780         struct ieee80211_hw *hw = priv->hw;
781         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
782         struct iwl_rate_scale_data *window = NULL;
783         struct iwl_rate_scale_data *search_win = NULL;
784         u32 tx_rate;
785         struct iwl_scale_tbl_info tbl_type;
786         struct iwl_scale_tbl_info *curr_tbl, *search_tbl;
787         u8 active_index = 0;
788         __le16 fc = hdr->frame_control;
789         s32 tpt = 0;
790
791         IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
792
793         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1))
794                 return;
795
796         /* This packet was aggregated but doesn't carry rate scale info */
797         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
798             !(info->flags & IEEE80211_TX_STAT_AMPDU))
799                 return;
800
801         retries = info->status.retry_count;
802
803         if (retries > 15)
804                 retries = 15;
805
806         lq_sta = (struct iwl_lq_sta *)priv_sta;
807
808         if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
809             !lq_sta->ibss_sta_added)
810                 goto out;
811
812         table = &lq_sta->lq;
813         active_index = lq_sta->active_tbl;
814
815         curr_tbl = &(lq_sta->lq_info[active_index]);
816         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
817         window = (struct iwl_rate_scale_data *)&(curr_tbl->win[0]);
818         search_win = (struct iwl_rate_scale_data *)&(search_tbl->win[0]);
819
820         /*
821          * Ignore this Tx frame response if its initial rate doesn't match
822          * that of latest Link Quality command.  There may be stragglers
823          * from a previous Link Quality command, but we're no longer interested
824          * in those; they're either from the "active" mode while we're trying
825          * to check "search" mode, or a prior "search" mode after we've moved
826          * to a new "search" mode (which might become the new "active" mode).
827          */
828         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
829         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
830         if (priv->band == IEEE80211_BAND_5GHZ)
831                 rs_index -= IWL_FIRST_OFDM_RATE;
832
833         if ((info->tx_rate_idx < 0) ||
834             (tbl_type.is_SGI ^
835                 !!(info->flags & IEEE80211_TX_CTL_SHORT_GI)) ||
836             (tbl_type.is_fat ^
837                 !!(info->flags & IEEE80211_TX_CTL_40_MHZ_WIDTH)) ||
838             (tbl_type.is_dup ^
839                 !!(info->flags & IEEE80211_TX_CTL_DUP_DATA)) ||
840             (tbl_type.ant_type ^ info->antenna_sel_tx) ||
841             (!!(tx_rate & RATE_MCS_HT_MSK) ^
842                 !!(info->flags & IEEE80211_TX_CTL_OFDM_HT)) ||
843             (!!(tx_rate & RATE_MCS_GF_MSK) ^
844                 !!(info->flags & IEEE80211_TX_CTL_GREEN_FIELD)) ||
845             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
846              hw->wiphy->bands[info->band]->bitrates[info->tx_rate_idx].bitrate)) {
847                 IWL_DEBUG_RATE("initial rate does not match 0x%x\n", tx_rate);
848                 goto out;
849         }
850
851         /* Update frame history window with "failure" for each Tx retry. */
852         while (retries) {
853                 /* Look up the rate and other info used for each tx attempt.
854                  * Each tx attempt steps one entry deeper in the rate table. */
855                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
856                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
857                                           &tbl_type, &rs_index);
858
859                 /* If type matches "search" table,
860                  * add failure to "search" history */
861                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
862                     (tbl_type.ant_type == search_tbl->ant_type) &&
863                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
864                         if (search_tbl->expected_tpt)
865                                 tpt = search_tbl->expected_tpt[rs_index];
866                         else
867                                 tpt = 0;
868                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
869
870                 /* Else if type matches "current/active" table,
871                  * add failure to "current/active" history */
872                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
873                            (tbl_type.ant_type == curr_tbl->ant_type) &&
874                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
875                         if (curr_tbl->expected_tpt)
876                                 tpt = curr_tbl->expected_tpt[rs_index];
877                         else
878                                 tpt = 0;
879                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
880                 }
881
882                 /* If not searching for a new mode, increment failed counter
883                  * ... this helps determine when to start searching again */
884                 if (lq_sta->stay_in_tbl)
885                         lq_sta->total_failed++;
886                 --retries;
887                 index++;
888
889         }
890
891         /*
892          * Find (by rate) the history window to update with final Tx attempt;
893          * if Tx was successful first try, use original rate,
894          * else look up the rate that was, finally, successful.
895          */
896         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
897         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
898
899         /* Update frame history window with "success" if Tx got ACKed ... */
900         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
901
902         /* If type matches "search" table,
903          * add final tx status to "search" history */
904         if ((tbl_type.lq_type == search_tbl->lq_type) &&
905             (tbl_type.ant_type == search_tbl->ant_type) &&
906             (tbl_type.is_SGI == search_tbl->is_SGI)) {
907                 if (search_tbl->expected_tpt)
908                         tpt = search_tbl->expected_tpt[rs_index];
909                 else
910                         tpt = 0;
911                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
912                         rs_collect_tx_data(search_win, rs_index, tpt,
913                                            info->status.ampdu_ack_len,
914                                            info->status.ampdu_ack_map);
915                 else
916                         rs_collect_tx_data(search_win, rs_index, tpt,
917                                            1, status);
918         /* Else if type matches "current/active" table,
919          * add final tx status to "current/active" history */
920         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
921                    (tbl_type.ant_type == curr_tbl->ant_type) &&
922                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
923                 if (curr_tbl->expected_tpt)
924                         tpt = curr_tbl->expected_tpt[rs_index];
925                 else
926                         tpt = 0;
927                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
928                         rs_collect_tx_data(window, rs_index, tpt,
929                                            info->status.ampdu_ack_len,
930                                            info->status.ampdu_ack_map);
931                 else
932                         rs_collect_tx_data(window, rs_index, tpt,
933                                            1, status);
934         }
935
936         /* If not searching for new mode, increment success/failed counter
937          * ... these help determine when to start searching again */
938         if (lq_sta->stay_in_tbl) {
939                 if (info->flags & IEEE80211_TX_CTL_AMPDU) {
940                         lq_sta->total_success += info->status.ampdu_ack_map;
941                         lq_sta->total_failed +=
942                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
943                 } else {
944                         if (status)
945                                 lq_sta->total_success++;
946                         else
947                                 lq_sta->total_failed++;
948                 }
949         }
950
951         /* See if there's a better rate or modulation mode to try. */
952         rs_rate_scale_perform(priv, hdr, sta, lq_sta);
953 out:
954         return;
955 }
956
957 /*
958  * Begin a period of staying with a selected modulation mode.
959  * Set "stay_in_tbl" flag to prevent any mode switches.
960  * Set frame tx success limits according to legacy vs. high-throughput,
961  * and reset overall (spanning all rates) tx success history statistics.
962  * These control how long we stay using same modulation mode before
963  * searching for a new mode.
964  */
965 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
966                                  struct iwl_lq_sta *lq_sta)
967 {
968         IWL_DEBUG_RATE("we are staying in the same table\n");
969         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
970         if (is_legacy) {
971                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
972                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
973                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
974         } else {
975                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
976                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
977                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
978         }
979         lq_sta->table_count = 0;
980         lq_sta->total_failed = 0;
981         lq_sta->total_success = 0;
982 }
983
984 /*
985  * Find correct throughput table for given mode of modulation
986  */
987 static void rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
988                                       struct iwl_scale_tbl_info *tbl)
989 {
990         if (is_legacy(tbl->lq_type)) {
991                 if (!is_a_band(tbl->lq_type))
992                         tbl->expected_tpt = expected_tpt_G;
993                 else
994                         tbl->expected_tpt = expected_tpt_A;
995         } else if (is_siso(tbl->lq_type)) {
996                 if (tbl->is_fat && !lq_sta->is_dup)
997                         if (tbl->is_SGI)
998                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
999                         else
1000                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1001                 else if (tbl->is_SGI)
1002                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1003                 else
1004                         tbl->expected_tpt = expected_tpt_siso20MHz;
1005
1006         } else if (is_mimo(tbl->lq_type)) { /* FIXME:need to separate mimo2/3 */
1007                 if (tbl->is_fat && !lq_sta->is_dup)
1008                         if (tbl->is_SGI)
1009                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
1010                         else
1011                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
1012                 else if (tbl->is_SGI)
1013                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
1014                 else
1015                         tbl->expected_tpt = expected_tpt_mimo20MHz;
1016         } else
1017                 tbl->expected_tpt = expected_tpt_G;
1018 }
1019
1020 /*
1021  * Find starting rate for new "search" high-throughput mode of modulation.
1022  * Goal is to find lowest expected rate (under perfect conditions) that is
1023  * above the current measured throughput of "active" mode, to give new mode
1024  * a fair chance to prove itself without too many challenges.
1025  *
1026  * This gets called when transitioning to more aggressive modulation
1027  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1028  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1029  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1030  * bit rate will typically need to increase, but not if performance was bad.
1031  */
1032 static s32 rs_get_best_rate(struct iwl_priv *priv,
1033                             struct iwl_lq_sta *lq_sta,
1034                             struct iwl_scale_tbl_info *tbl,     /* "search" */
1035                             u16 rate_mask, s8 index)
1036 {
1037         /* "active" values */
1038         struct iwl_scale_tbl_info *active_tbl =
1039             &(lq_sta->lq_info[lq_sta->active_tbl]);
1040         s32 active_sr = active_tbl->win[index].success_ratio;
1041         s32 active_tpt = active_tbl->expected_tpt[index];
1042
1043         /* expected "search" throughput */
1044         s32 *tpt_tbl = tbl->expected_tpt;
1045
1046         s32 new_rate, high, low, start_hi;
1047         u16 high_low;
1048         s8 rate = index;
1049
1050         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1051
1052         for (; ;) {
1053                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1054                                                 tbl->lq_type);
1055
1056                 low = high_low & 0xff;
1057                 high = (high_low >> 8) & 0xff;
1058
1059                 /*
1060                  * Lower the "search" bit rate, to give new "search" mode
1061                  * approximately the same throughput as "active" if:
1062                  *
1063                  * 1) "Active" mode has been working modestly well (but not
1064                  *    great), and expected "search" throughput (under perfect
1065                  *    conditions) at candidate rate is above the actual
1066                  *    measured "active" throughput (but less than expected
1067                  *    "active" throughput under perfect conditions).
1068                  * OR
1069                  * 2) "Active" mode has been working perfectly or very well
1070                  *    and expected "search" throughput (under perfect
1071                  *    conditions) at candidate rate is above expected
1072                  *    "active" throughput (under perfect conditions).
1073                  */
1074                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1075                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1076                       (active_sr <= IWL_RATE_HIGH_TH) &&
1077                       (tpt_tbl[rate] <= active_tpt))) ||
1078                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1079                      (tpt_tbl[rate] > active_tpt))) {
1080
1081                         /* (2nd or later pass)
1082                          * If we've already tried to raise the rate, and are
1083                          * now trying to lower it, use the higher rate. */
1084                         if (start_hi != IWL_RATE_INVALID) {
1085                                 new_rate = start_hi;
1086                                 break;
1087                         }
1088
1089                         new_rate = rate;
1090
1091                         /* Loop again with lower rate */
1092                         if (low != IWL_RATE_INVALID)
1093                                 rate = low;
1094
1095                         /* Lower rate not available, use the original */
1096                         else
1097                                 break;
1098
1099                 /* Else try to raise the "search" rate to match "active" */
1100                 } else {
1101                         /* (2nd or later pass)
1102                          * If we've already tried to lower the rate, and are
1103                          * now trying to raise it, use the lower rate. */
1104                         if (new_rate != IWL_RATE_INVALID)
1105                                 break;
1106
1107                         /* Loop again with higher rate */
1108                         else if (high != IWL_RATE_INVALID) {
1109                                 start_hi = high;
1110                                 rate = high;
1111
1112                         /* Higher rate not available, use the original */
1113                         } else {
1114                                 new_rate = rate;
1115                                 break;
1116                         }
1117                 }
1118         }
1119
1120         return new_rate;
1121 }
1122
1123 /*
1124  * Set up search table for MIMO
1125  */
1126 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1127                              struct iwl_lq_sta *lq_sta,
1128                              struct ieee80211_conf *conf,
1129                              struct ieee80211_sta *sta,
1130                              struct iwl_scale_tbl_info *tbl, int index)
1131 {
1132         u16 rate_mask;
1133         s32 rate;
1134         s8 is_green = lq_sta->is_green;
1135
1136         if (!conf->ht.enabled || !sta->ht_cap.ht_supported)
1137                 return -1;
1138
1139         if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1140                                                 == WLAN_HT_CAP_SM_PS_STATIC)
1141                 return -1;
1142
1143         /* Need both Tx chains/antennas to support MIMO */
1144         if (priv->hw_params.tx_chains_num < 2)
1145                 return -1;
1146
1147         IWL_DEBUG_RATE("LQ: try to switch to MIMO2\n");
1148
1149         tbl->lq_type = LQ_MIMO2;
1150         tbl->is_dup = lq_sta->is_dup;
1151         tbl->action = 0;
1152         rate_mask = lq_sta->active_mimo2_rate;
1153
1154         if (priv->current_ht_config.supported_chan_width
1155                                         == IWL_CHANNEL_WIDTH_40MHZ)
1156                 tbl->is_fat = 1;
1157         else
1158                 tbl->is_fat = 0;
1159
1160         /* FIXME: - don't toggle SGI here
1161         if (tbl->is_fat) {
1162                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1163                         tbl->is_SGI = 1;
1164                 else
1165                         tbl->is_SGI = 0;
1166         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1167                 tbl->is_SGI = 1;
1168         else
1169                 tbl->is_SGI = 0;
1170         */
1171
1172         rs_set_expected_tpt_table(lq_sta, tbl);
1173
1174         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1175
1176         IWL_DEBUG_RATE("LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1177
1178         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1179                 IWL_DEBUG_RATE("Can't switch with index %d rate mask %x\n",
1180                                                 rate, rate_mask);
1181                 return -1;
1182         }
1183         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1184
1185         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1186                      tbl->current_rate, is_green);
1187         return 0;
1188 }
1189
1190 /*
1191  * Set up search table for SISO
1192  */
1193 static int rs_switch_to_siso(struct iwl_priv *priv,
1194                              struct iwl_lq_sta *lq_sta,
1195                              struct ieee80211_conf *conf,
1196                              struct ieee80211_sta *sta,
1197                              struct iwl_scale_tbl_info *tbl, int index)
1198 {
1199         u16 rate_mask;
1200         u8 is_green = lq_sta->is_green;
1201         s32 rate;
1202
1203         if (!conf->ht.enabled || !sta->ht_cap.ht_supported)
1204                 return -1;
1205
1206         IWL_DEBUG_RATE("LQ: try to switch to SISO\n");
1207
1208         tbl->is_dup = lq_sta->is_dup;
1209         tbl->lq_type = LQ_SISO;
1210         tbl->action = 0;
1211         rate_mask = lq_sta->active_siso_rate;
1212
1213         if (priv->current_ht_config.supported_chan_width
1214             == IWL_CHANNEL_WIDTH_40MHZ)
1215                 tbl->is_fat = 1;
1216         else
1217                 tbl->is_fat = 0;
1218
1219         /* FIXME: - don't toggle SGI here
1220         if (tbl->is_fat) {
1221                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1222                         tbl->is_SGI = 1;
1223                 else
1224                         tbl->is_SGI = 0;
1225         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1226                 tbl->is_SGI = 1;
1227         else
1228                 tbl->is_SGI = 0;
1229         */
1230
1231         if (is_green)
1232                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1233
1234         rs_set_expected_tpt_table(lq_sta, tbl);
1235         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1236
1237         IWL_DEBUG_RATE("LQ: get best rate %d mask %X\n", rate, rate_mask);
1238         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1239                 IWL_DEBUG_RATE("can not switch with index %d rate mask %x\n",
1240                              rate, rate_mask);
1241                 return -1;
1242         }
1243         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1244         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1245                      tbl->current_rate, is_green);
1246         return 0;
1247 }
1248
1249 /*
1250  * Try to switch to new modulation mode from legacy
1251  */
1252 static int rs_move_legacy_other(struct iwl_priv *priv,
1253                                 struct iwl_lq_sta *lq_sta,
1254                                 struct ieee80211_conf *conf,
1255                                 struct ieee80211_sta *sta,
1256                                 int index)
1257 {
1258         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1259         struct iwl_scale_tbl_info *search_tbl =
1260                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1261         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1262         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1263                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1264         u8 start_action = tbl->action;
1265         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1266         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1267         int ret = 0;
1268
1269         for (; ;) {
1270                 switch (tbl->action) {
1271                 case IWL_LEGACY_SWITCH_ANTENNA1:
1272                 case IWL_LEGACY_SWITCH_ANTENNA2:
1273                         IWL_DEBUG_RATE("LQ: Legacy toggle Antenna\n");
1274
1275                         lq_sta->action_counter++;
1276
1277                         if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1278                                                         tx_chains_num <= 1) ||
1279                             (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1280                                                         tx_chains_num <= 2))
1281                                 break;
1282
1283                         /* Don't change antenna if success has been great */
1284                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1285                                 break;
1286
1287                         /* Set up search table to try other antenna */
1288                         memcpy(search_tbl, tbl, sz);
1289
1290                         if (rs_toggle_antenna(valid_tx_ant,
1291                                 &search_tbl->current_rate, search_tbl)) {
1292                                 rs_set_expected_tpt_table(lq_sta, search_tbl);
1293                                 goto out;
1294                         }
1295                         break;
1296                 case IWL_LEGACY_SWITCH_SISO:
1297                         IWL_DEBUG_RATE("LQ: Legacy switch to SISO\n");
1298
1299                         /* Set up search table to try SISO */
1300                         memcpy(search_tbl, tbl, sz);
1301                         search_tbl->is_SGI = 0;
1302                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1303                                                  search_tbl, index);
1304                         if (!ret) {
1305                                 lq_sta->action_counter = 0;
1306                                 goto out;
1307                         }
1308
1309                         break;
1310                 case IWL_LEGACY_SWITCH_MIMO2_AB:
1311                 case IWL_LEGACY_SWITCH_MIMO2_AC:
1312                 case IWL_LEGACY_SWITCH_MIMO2_BC:
1313                         IWL_DEBUG_RATE("LQ: Legacy switch to MIMO2\n");
1314
1315                         /* Set up search table to try MIMO */
1316                         memcpy(search_tbl, tbl, sz);
1317                         search_tbl->is_SGI = 0;
1318
1319                         if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1320                                 search_tbl->ant_type = ANT_AB;
1321                         else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1322                                 search_tbl->ant_type = ANT_AC;
1323                         else
1324                                 search_tbl->ant_type = ANT_BC;
1325
1326                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1327                                 break;
1328
1329                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1330                                                  search_tbl, index);
1331                         if (!ret) {
1332                                 lq_sta->action_counter = 0;
1333                                 goto out;
1334                         }
1335                         break;
1336                 }
1337                 tbl->action++;
1338                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1339                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1340
1341                 if (tbl->action == start_action)
1342                         break;
1343
1344         }
1345         search_tbl->lq_type = LQ_NONE;
1346         return 0;
1347
1348 out:
1349         lq_sta->search_better_tbl = 1;
1350         tbl->action++;
1351         if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1352                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1353         return 0;
1354
1355 }
1356
1357 /*
1358  * Try to switch to new modulation mode from SISO
1359  */
1360 static int rs_move_siso_to_other(struct iwl_priv *priv,
1361                                  struct iwl_lq_sta *lq_sta,
1362                                  struct ieee80211_conf *conf,
1363                                  struct ieee80211_sta *sta, int index)
1364 {
1365         u8 is_green = lq_sta->is_green;
1366         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1367         struct iwl_scale_tbl_info *search_tbl =
1368                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1369         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1370         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1371                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1372         u8 start_action = tbl->action;
1373         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1374         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1375         int ret;
1376
1377         for (;;) {
1378                 lq_sta->action_counter++;
1379                 switch (tbl->action) {
1380                 case IWL_SISO_SWITCH_ANTENNA1:
1381                 case IWL_SISO_SWITCH_ANTENNA2:
1382                         IWL_DEBUG_RATE("LQ: SISO toggle Antenna\n");
1383
1384                         if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1385                                                         tx_chains_num <= 1) ||
1386                             (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1387                                                         tx_chains_num <= 2))
1388                                 break;
1389
1390                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1391                                 break;
1392
1393                         memcpy(search_tbl, tbl, sz);
1394                         if (rs_toggle_antenna(valid_tx_ant,
1395                                        &search_tbl->current_rate, search_tbl))
1396                                 goto out;
1397                         break;
1398                 case IWL_SISO_SWITCH_MIMO2_AB:
1399                 case IWL_SISO_SWITCH_MIMO2_AC:
1400                 case IWL_SISO_SWITCH_MIMO2_BC:
1401                         IWL_DEBUG_RATE("LQ: SISO switch to MIMO2\n");
1402                         memcpy(search_tbl, tbl, sz);
1403                         search_tbl->is_SGI = 0;
1404
1405                         if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1406                                 search_tbl->ant_type = ANT_AB;
1407                         else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1408                                 search_tbl->ant_type = ANT_AC;
1409                         else
1410                                 search_tbl->ant_type = ANT_BC;
1411
1412                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1413                                 break;
1414
1415                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1416                                                  search_tbl, index);
1417                         if (!ret)
1418                                 goto out;
1419                         break;
1420                 case IWL_SISO_SWITCH_GI:
1421                         if (!tbl->is_fat &&
1422                                 !(priv->current_ht_config.sgf &
1423                                                 HT_SHORT_GI_20MHZ))
1424                                 break;
1425                         if (tbl->is_fat &&
1426                                 !(priv->current_ht_config.sgf &
1427                                                 HT_SHORT_GI_40MHZ))
1428                                 break;
1429
1430                         IWL_DEBUG_RATE("LQ: SISO toggle SGI/NGI\n");
1431
1432                         memcpy(search_tbl, tbl, sz);
1433                         if (is_green) {
1434                                 if (!tbl->is_SGI)
1435                                         break;
1436                                 else
1437                                         IWL_ERROR("SGI was set in GF+SISO\n");
1438                         }
1439                         search_tbl->is_SGI = !tbl->is_SGI;
1440                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1441                         if (tbl->is_SGI) {
1442                                 s32 tpt = lq_sta->last_tpt / 100;
1443                                 if (tpt >= search_tbl->expected_tpt[index])
1444                                         break;
1445                         }
1446                         search_tbl->current_rate = rate_n_flags_from_tbl(
1447                                                 search_tbl, index, is_green);
1448                         goto out;
1449                 }
1450                 tbl->action++;
1451                 if (tbl->action > IWL_SISO_SWITCH_GI)
1452                         tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1453
1454                 if (tbl->action == start_action)
1455                         break;
1456         }
1457         search_tbl->lq_type = LQ_NONE;
1458         return 0;
1459
1460  out:
1461         lq_sta->search_better_tbl = 1;
1462         tbl->action++;
1463         if (tbl->action > IWL_SISO_SWITCH_GI)
1464                 tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1465         return 0;
1466 }
1467
1468 /*
1469  * Try to switch to new modulation mode from MIMO
1470  */
1471 static int rs_move_mimo_to_other(struct iwl_priv *priv,
1472                                  struct iwl_lq_sta *lq_sta,
1473                                  struct ieee80211_conf *conf,
1474                                  struct ieee80211_sta *sta, int index)
1475 {
1476         s8 is_green = lq_sta->is_green;
1477         struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1478         struct iwl_scale_tbl_info *search_tbl =
1479                                 &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1480         struct iwl_rate_scale_data *window = &(tbl->win[index]);
1481         u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1482                   (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1483         u8 start_action = tbl->action;
1484         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1485         u8 tx_chains_num = priv->hw_params.tx_chains_num;
1486         int ret;
1487
1488         for (;;) {
1489                 lq_sta->action_counter++;
1490                 switch (tbl->action) {
1491                 case IWL_MIMO2_SWITCH_ANTENNA1:
1492                 case IWL_MIMO2_SWITCH_ANTENNA2:
1493                         IWL_DEBUG_RATE("LQ: MIMO toggle Antennas\n");
1494
1495                         if (tx_chains_num <= 2)
1496                                 break;
1497
1498                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1499                                 break;
1500
1501                         memcpy(search_tbl, tbl, sz);
1502                         if (rs_toggle_antenna(valid_tx_ant,
1503                                        &search_tbl->current_rate, search_tbl))
1504                                 goto out;
1505                         break;
1506                 case IWL_MIMO2_SWITCH_SISO_A:
1507                 case IWL_MIMO2_SWITCH_SISO_B:
1508                 case IWL_MIMO2_SWITCH_SISO_C:
1509                         IWL_DEBUG_RATE("LQ: MIMO2 switch to SISO\n");
1510
1511                         /* Set up new search table for SISO */
1512                         memcpy(search_tbl, tbl, sz);
1513
1514                         if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1515                                 search_tbl->ant_type = ANT_A;
1516                         else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1517                                 search_tbl->ant_type = ANT_B;
1518                         else
1519                                 search_tbl->ant_type = ANT_C;
1520
1521                         if (!rs_is_valid_ant(valid_tx_ant, search_tbl->ant_type))
1522                                 break;
1523
1524                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1525                                                  search_tbl, index);
1526                         if (!ret)
1527                                 goto out;
1528
1529                         break;
1530
1531                 case IWL_MIMO2_SWITCH_GI:
1532                         if (!tbl->is_fat &&
1533                                 !(priv->current_ht_config.sgf &
1534                                                 HT_SHORT_GI_20MHZ))
1535                                 break;
1536                         if (tbl->is_fat &&
1537                                 !(priv->current_ht_config.sgf &
1538                                                 HT_SHORT_GI_40MHZ))
1539                                 break;
1540
1541                         IWL_DEBUG_RATE("LQ: MIMO toggle SGI/NGI\n");
1542
1543                         /* Set up new search table for MIMO */
1544                         memcpy(search_tbl, tbl, sz);
1545                         search_tbl->is_SGI = !tbl->is_SGI;
1546                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1547                         /*
1548                          * If active table already uses the fastest possible
1549                          * modulation (dual stream with short guard interval),
1550                          * and it's working well, there's no need to look
1551                          * for a better type of modulation!
1552                          */
1553                         if (tbl->is_SGI) {
1554                                 s32 tpt = lq_sta->last_tpt / 100;
1555                                 if (tpt >= search_tbl->expected_tpt[index])
1556                                         break;
1557                         }
1558                         search_tbl->current_rate = rate_n_flags_from_tbl(
1559                                                 search_tbl, index, is_green);
1560                         goto out;
1561
1562                 }
1563                 tbl->action++;
1564                 if (tbl->action > IWL_MIMO2_SWITCH_GI)
1565                         tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1566
1567                 if (tbl->action == start_action)
1568                         break;
1569         }
1570         search_tbl->lq_type = LQ_NONE;
1571         return 0;
1572  out:
1573         lq_sta->search_better_tbl = 1;
1574         tbl->action++;
1575         if (tbl->action > IWL_MIMO2_SWITCH_GI)
1576                 tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1577         return 0;
1578
1579 }
1580
1581 /*
1582  * Check whether we should continue using same modulation mode, or
1583  * begin search for a new mode, based on:
1584  * 1) # tx successes or failures while using this mode
1585  * 2) # times calling this function
1586  * 3) elapsed time in this mode (not used, for now)
1587  */
1588 static void rs_stay_in_table(struct iwl_lq_sta *lq_sta)
1589 {
1590         struct iwl_scale_tbl_info *tbl;
1591         int i;
1592         int active_tbl;
1593         int flush_interval_passed = 0;
1594         struct iwl_priv *priv;
1595
1596         priv = lq_sta->drv;
1597         active_tbl = lq_sta->active_tbl;
1598
1599         tbl = &(lq_sta->lq_info[active_tbl]);
1600
1601         /* If we've been disallowing search, see if we should now allow it */
1602         if (lq_sta->stay_in_tbl) {
1603
1604                 /* Elapsed time using current modulation mode */
1605                 if (lq_sta->flush_timer)
1606                         flush_interval_passed =
1607                             time_after(jiffies,
1608                                        (unsigned long)(lq_sta->flush_timer +
1609                                         IWL_RATE_SCALE_FLUSH_INTVL));
1610
1611                 /*
1612                  * Check if we should allow search for new modulation mode.
1613                  * If many frames have failed or succeeded, or we've used
1614                  * this same modulation for a long time, allow search, and
1615                  * reset history stats that keep track of whether we should
1616                  * allow a new search.  Also (below) reset all bitmaps and
1617                  * stats in active history.
1618                  */
1619                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1620                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1621                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1622                      && (flush_interval_passed))) {
1623                         IWL_DEBUG_RATE("LQ: stay is expired %d %d %d\n:",
1624                                      lq_sta->total_failed,
1625                                      lq_sta->total_success,
1626                                      flush_interval_passed);
1627
1628                         /* Allow search for new mode */
1629                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1630                         lq_sta->total_failed = 0;
1631                         lq_sta->total_success = 0;
1632                         lq_sta->flush_timer = 0;
1633
1634                 /*
1635                  * Else if we've used this modulation mode enough repetitions
1636                  * (regardless of elapsed time or success/failure), reset
1637                  * history bitmaps and rate-specific stats for all rates in
1638                  * active table.
1639                  */
1640                 } else {
1641                         lq_sta->table_count++;
1642                         if (lq_sta->table_count >=
1643                             lq_sta->table_count_limit) {
1644                                 lq_sta->table_count = 0;
1645
1646                                 IWL_DEBUG_RATE("LQ: stay in table clear win\n");
1647                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1648                                         rs_rate_scale_clear_window(
1649                                                 &(tbl->win[i]));
1650                         }
1651                 }
1652
1653                 /* If transitioning to allow "search", reset all history
1654                  * bitmaps and stats in active table (this will become the new
1655                  * "search" table). */
1656                 if (!lq_sta->stay_in_tbl) {
1657                         for (i = 0; i < IWL_RATE_COUNT; i++)
1658                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1659                 }
1660         }
1661 }
1662
1663 /*
1664  * Do rate scaling and search for new modulation mode.
1665  */
1666 static void rs_rate_scale_perform(struct iwl_priv *priv,
1667                                   struct ieee80211_hdr *hdr,
1668                                   struct ieee80211_sta *sta,
1669                                   struct iwl_lq_sta *lq_sta)
1670 {
1671         struct ieee80211_hw *hw = priv->hw;
1672         struct ieee80211_conf *conf = &hw->conf;
1673         int low = IWL_RATE_INVALID;
1674         int high = IWL_RATE_INVALID;
1675         int index;
1676         int i;
1677         struct iwl_rate_scale_data *window = NULL;
1678         int current_tpt = IWL_INVALID_VALUE;
1679         int low_tpt = IWL_INVALID_VALUE;
1680         int high_tpt = IWL_INVALID_VALUE;
1681         u32 fail_count;
1682         s8 scale_action = 0;
1683         __le16 fc;
1684         u16 rate_mask;
1685         u8 update_lq = 0;
1686         struct iwl_scale_tbl_info *tbl, *tbl1;
1687         u16 rate_scale_index_msk = 0;
1688         u32 rate;
1689         u8 is_green = 0;
1690         u8 active_tbl = 0;
1691         u8 done_search = 0;
1692         u16 high_low;
1693         s32 sr;
1694         u8 tid = MAX_TID_COUNT;
1695
1696         IWL_DEBUG_RATE("rate scale calculate new rate for skb\n");
1697
1698         fc = hdr->frame_control;
1699         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1)) {
1700                 /* Send management frames and broadcast/multicast data using
1701                  * lowest rate. */
1702                 /* TODO: this could probably be improved.. */
1703                 return;
1704         }
1705
1706         if (!sta || !lq_sta)
1707                 return;
1708
1709         lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1710
1711         tid = rs_tl_add_packet(lq_sta, hdr);
1712
1713         /*
1714          * Select rate-scale / modulation-mode table to work with in
1715          * the rest of this function:  "search" if searching for better
1716          * modulation mode, or "active" if doing rate scaling within a mode.
1717          */
1718         if (!lq_sta->search_better_tbl)
1719                 active_tbl = lq_sta->active_tbl;
1720         else
1721                 active_tbl = 1 - lq_sta->active_tbl;
1722
1723         tbl = &(lq_sta->lq_info[active_tbl]);
1724         is_green = lq_sta->is_green;
1725
1726         /* current tx rate */
1727         index = lq_sta->last_txrate_idx;
1728
1729         IWL_DEBUG_RATE("Rate scale index %d for type %d\n", index,
1730                        tbl->lq_type);
1731
1732         /* rates available for this association, and for modulation mode */
1733         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1734
1735         IWL_DEBUG_RATE("mask 0x%04X \n", rate_mask);
1736
1737         /* mask with station rate restriction */
1738         if (is_legacy(tbl->lq_type)) {
1739                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
1740                         /* supp_rates has no CCK bits in A mode */
1741                         rate_scale_index_msk = (u16) (rate_mask &
1742                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1743                 else
1744                         rate_scale_index_msk = (u16) (rate_mask &
1745                                                       lq_sta->supp_rates);
1746
1747         } else
1748                 rate_scale_index_msk = rate_mask;
1749
1750         if (!rate_scale_index_msk)
1751                 rate_scale_index_msk = rate_mask;
1752
1753         if (!((1 << index) & rate_scale_index_msk)) {
1754                 IWL_ERROR("Current Rate is not valid\n");
1755                 return;
1756         }
1757
1758         /* Get expected throughput table and history window for current rate */
1759         if (!tbl->expected_tpt) {
1760                 IWL_ERROR("tbl->expected_tpt is NULL\n");
1761                 return;
1762         }
1763
1764         window = &(tbl->win[index]);
1765
1766         /*
1767          * If there is not enough history to calculate actual average
1768          * throughput, keep analyzing results of more tx frames, without
1769          * changing rate or mode (bypass most of the rest of this function).
1770          * Set up new rate table in uCode only if old rate is not supported
1771          * in current association (use new rate found above).
1772          */
1773         fail_count = window->counter - window->success_counter;
1774         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1775                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
1776                 IWL_DEBUG_RATE("LQ: still below TH. succ=%d total=%d "
1777                                "for index %d\n",
1778                                window->success_counter, window->counter, index);
1779
1780                 /* Can't calculate this yet; not enough history */
1781                 window->average_tpt = IWL_INVALID_VALUE;
1782
1783                 /* Should we stay with this modulation mode,
1784                  * or search for a new one? */
1785                 rs_stay_in_table(lq_sta);
1786
1787                 goto out;
1788         }
1789
1790         /* Else we have enough samples; calculate estimate of
1791          * actual average throughput */
1792
1793         BUG_ON(window->average_tpt != ((window->success_ratio *
1794                         tbl->expected_tpt[index] + 64) / 128));
1795
1796         /* If we are searching for better modulation mode, check success. */
1797         if (lq_sta->search_better_tbl) {
1798
1799                 /* If good success, continue using the "search" mode;
1800                  * no need to send new link quality command, since we're
1801                  * continuing to use the setup that we've been trying. */
1802                 if (window->average_tpt > lq_sta->last_tpt) {
1803
1804                         IWL_DEBUG_RATE("LQ: SWITCHING TO NEW TABLE "
1805                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1806                                         window->success_ratio,
1807                                         window->average_tpt,
1808                                         lq_sta->last_tpt);
1809
1810                         if (!is_legacy(tbl->lq_type))
1811                                 lq_sta->enable_counter = 1;
1812
1813                         /* Swap tables; "search" becomes "active" */
1814                         lq_sta->active_tbl = active_tbl;
1815                         current_tpt = window->average_tpt;
1816
1817                 /* Else poor success; go back to mode in "active" table */
1818                 } else {
1819
1820                         IWL_DEBUG_RATE("LQ: GOING BACK TO THE OLD TABLE "
1821                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1822                                         window->success_ratio,
1823                                         window->average_tpt,
1824                                         lq_sta->last_tpt);
1825
1826                         /* Nullify "search" table */
1827                         tbl->lq_type = LQ_NONE;
1828
1829                         /* Revert to "active" table */
1830                         active_tbl = lq_sta->active_tbl;
1831                         tbl = &(lq_sta->lq_info[active_tbl]);
1832
1833                         /* Revert to "active" rate and throughput info */
1834                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1835                         current_tpt = lq_sta->last_tpt;
1836
1837                         /* Need to set up a new rate table in uCode */
1838                         update_lq = 1;
1839                 }
1840
1841                 /* Either way, we've made a decision; modulation mode
1842                  * search is done, allow rate adjustment next time. */
1843                 lq_sta->search_better_tbl = 0;
1844                 done_search = 1;        /* Don't switch modes below! */
1845                 goto lq_update;
1846         }
1847
1848         /* (Else) not in search of better modulation mode, try for better
1849          * starting rate, while staying in this mode. */
1850         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
1851                                         tbl->lq_type);
1852         low = high_low & 0xff;
1853         high = (high_low >> 8) & 0xff;
1854
1855         sr = window->success_ratio;
1856
1857         /* Collect measured throughputs for current and adjacent rates */
1858         current_tpt = window->average_tpt;
1859         if (low != IWL_RATE_INVALID)
1860                 low_tpt = tbl->win[low].average_tpt;
1861         if (high != IWL_RATE_INVALID)
1862                 high_tpt = tbl->win[high].average_tpt;
1863
1864         scale_action = 0;
1865
1866         /* Too many failures, decrease rate */
1867         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
1868                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
1869                 scale_action = -1;
1870
1871         /* No throughput measured yet for adjacent rates; try increase. */
1872         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1873                    (high_tpt == IWL_INVALID_VALUE)) {
1874
1875                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
1876                         scale_action = 1;
1877                 else if (low != IWL_RATE_INVALID)
1878                         scale_action = -1;
1879         }
1880
1881         /* Both adjacent throughputs are measured, but neither one has better
1882          * throughput; we're using the best rate, don't change it! */
1883         else if ((low_tpt != IWL_INVALID_VALUE) &&
1884                  (high_tpt != IWL_INVALID_VALUE) &&
1885                  (low_tpt < current_tpt) &&
1886                  (high_tpt < current_tpt))
1887                 scale_action = 0;
1888
1889         /* At least one adjacent rate's throughput is measured,
1890          * and may have better performance. */
1891         else {
1892                 /* Higher adjacent rate's throughput is measured */
1893                 if (high_tpt != IWL_INVALID_VALUE) {
1894                         /* Higher rate has better throughput */
1895                         if (high_tpt > current_tpt &&
1896                                         sr >= IWL_RATE_INCREASE_TH) {
1897                                 scale_action = 1;
1898                         } else {
1899                                 IWL_DEBUG_RATE
1900                                     ("decrease rate because of high tpt\n");
1901                                 scale_action = -1;
1902                         }
1903
1904                 /* Lower adjacent rate's throughput is measured */
1905                 } else if (low_tpt != IWL_INVALID_VALUE) {
1906                         /* Lower rate has better throughput */
1907                         if (low_tpt > current_tpt) {
1908                                 IWL_DEBUG_RATE
1909                                     ("decrease rate because of low tpt\n");
1910                                 scale_action = -1;
1911                         } else if (sr >= IWL_RATE_INCREASE_TH) {
1912                                 scale_action = 1;
1913                         }
1914                 }
1915         }
1916
1917         /* Sanity check; asked for decrease, but success rate or throughput
1918          * has been good at old rate.  Don't change it. */
1919         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
1920                     ((sr > IWL_RATE_HIGH_TH) ||
1921                      (current_tpt > (100 * tbl->expected_tpt[low]))))
1922                 scale_action = 0;
1923
1924         switch (scale_action) {
1925         case -1:
1926                 /* Decrease starting rate, update uCode's rate table */
1927                 if (low != IWL_RATE_INVALID) {
1928                         update_lq = 1;
1929                         index = low;
1930                 }
1931                 break;
1932         case 1:
1933                 /* Increase starting rate, update uCode's rate table */
1934                 if (high != IWL_RATE_INVALID) {
1935                         update_lq = 1;
1936                         index = high;
1937                 }
1938
1939                 break;
1940         case 0:
1941                 /* No change */
1942         default:
1943                 break;
1944         }
1945
1946         IWL_DEBUG_RATE("choose rate scale index %d action %d low %d "
1947                     "high %d type %d\n",
1948                      index, scale_action, low, high, tbl->lq_type);
1949
1950 lq_update:
1951         /* Replace uCode's rate table for the destination station. */
1952         if (update_lq) {
1953                 rate = rate_n_flags_from_tbl(tbl, index, is_green);
1954                 rs_fill_link_cmd(priv, lq_sta, rate);
1955                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1956         }
1957
1958         /* Should we stay with this modulation mode, or search for a new one? */
1959         rs_stay_in_table(lq_sta);
1960
1961         /*
1962          * Search for new modulation mode if we're:
1963          * 1)  Not changing rates right now
1964          * 2)  Not just finishing up a search
1965          * 3)  Allowing a new search
1966          */
1967         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
1968                 /* Save current throughput to compare with "search" throughput*/
1969                 lq_sta->last_tpt = current_tpt;
1970
1971                 /* Select a new "search" modulation mode to try.
1972                  * If one is found, set up the new "search" table. */
1973                 if (is_legacy(tbl->lq_type))
1974                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
1975                 else if (is_siso(tbl->lq_type))
1976                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
1977                 else
1978                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
1979
1980                 /* If new "search" mode was selected, set up in uCode table */
1981                 if (lq_sta->search_better_tbl) {
1982                         /* Access the "search" table, clear its history. */
1983                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1984                         for (i = 0; i < IWL_RATE_COUNT; i++)
1985                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1986
1987                         /* Use new "search" start rate */
1988                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1989
1990                         IWL_DEBUG_RATE("Switch current  mcs: %X index: %d\n",
1991                                      tbl->current_rate, index);
1992                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
1993                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1994                 }
1995
1996                 /* If the "active" (non-search) mode was legacy,
1997                  * and we've tried switching antennas,
1998                  * but we haven't been able to try HT modes (not available),
1999                  * stay with best antenna legacy modulation for a while
2000                  * before next round of mode comparisons. */
2001                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2002                 if (is_legacy(tbl1->lq_type) && !conf->ht.enabled &&
2003                     lq_sta->action_counter >= 1) {
2004                         lq_sta->action_counter = 0;
2005                         IWL_DEBUG_RATE("LQ: STAY in legacy table\n");
2006                         rs_set_stay_in_table(priv, 1, lq_sta);
2007                 }
2008
2009                 /* If we're in an HT mode, and all 3 mode switch actions
2010                  * have been tried and compared, stay in this best modulation
2011                  * mode for a while before next round of mode comparisons. */
2012                 if (lq_sta->enable_counter &&
2013                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
2014                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2015                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2016                             (tid != MAX_TID_COUNT)) {
2017                                 IWL_DEBUG_RATE("try to aggregate tid %d\n", tid);
2018                                 rs_tl_turn_on_agg(priv, tid, lq_sta, sta);
2019                         }
2020                         lq_sta->action_counter = 0;
2021                         rs_set_stay_in_table(priv, 0, lq_sta);
2022                 }
2023
2024         /*
2025          * Else, don't search for a new modulation mode.
2026          * Put new timestamp in stay-in-modulation-mode flush timer if:
2027          * 1)  Not changing rates right now
2028          * 2)  Not just finishing up a search
2029          * 3)  flush timer is empty
2030          */
2031         } else {
2032                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
2033                         lq_sta->flush_timer = jiffies;
2034         }
2035
2036 out:
2037         tbl->current_rate = rate_n_flags_from_tbl(tbl, index, is_green);
2038         i = index;
2039         lq_sta->last_txrate_idx = i;
2040
2041         return;
2042 }
2043
2044
2045 static void rs_initialize_lq(struct iwl_priv *priv,
2046                              struct ieee80211_conf *conf,
2047                              struct ieee80211_sta *sta,
2048                              struct iwl_lq_sta *lq_sta)
2049 {
2050         struct iwl_scale_tbl_info *tbl;
2051         int rate_idx;
2052         int i;
2053         u32 rate;
2054         u8 use_green = rs_use_green(priv, conf);
2055         u8 active_tbl = 0;
2056         u8 valid_tx_ant;
2057
2058         if (!sta || !lq_sta)
2059                 goto out;
2060
2061         i = lq_sta->last_txrate_idx;
2062
2063         if ((lq_sta->lq.sta_id == 0xff) &&
2064             (priv->iw_mode == NL80211_IFTYPE_ADHOC))
2065                 goto out;
2066
2067         valid_tx_ant = priv->hw_params.valid_tx_ant;
2068
2069         if (!lq_sta->search_better_tbl)
2070                 active_tbl = lq_sta->active_tbl;
2071         else
2072                 active_tbl = 1 - lq_sta->active_tbl;
2073
2074         tbl = &(lq_sta->lq_info[active_tbl]);
2075
2076         if ((i < 0) || (i >= IWL_RATE_COUNT))
2077                 i = 0;
2078
2079         /* FIXME:RS: This is also wrong in 4965 */
2080         rate = iwl_rates[i].plcp;
2081         rate |= RATE_MCS_ANT_B_MSK;
2082         rate &= ~RATE_MCS_ANT_A_MSK;
2083
2084         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2085                 rate |= RATE_MCS_CCK_MSK;
2086
2087         tbl->ant_type = ANT_B;
2088         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2089         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2090             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2091
2092         rate = rate_n_flags_from_tbl(tbl, rate_idx, use_green);
2093         tbl->current_rate = rate;
2094         rs_set_expected_tpt_table(lq_sta, tbl);
2095         rs_fill_link_cmd(NULL, lq_sta, rate);
2096         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2097  out:
2098         return;
2099 }
2100
2101 static void rs_get_rate(void *priv_r, struct ieee80211_supported_band *sband,
2102                         struct ieee80211_sta *sta, void *priv_sta,
2103                         struct sk_buff *skb, struct rate_selection *sel)
2104 {
2105
2106         int i;
2107         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2108         struct ieee80211_conf *conf = &priv->hw->conf;
2109         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2110         __le16 fc;
2111         struct iwl_lq_sta *lq_sta;
2112
2113         IWL_DEBUG_RATE_LIMIT("rate scale calculate new rate for skb\n");
2114
2115         /* Send management frames and broadcast/multicast data using lowest
2116          * rate. */
2117         fc = hdr->frame_control;
2118         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1) ||
2119             !sta || !priv_sta) {
2120                 sel->rate_idx = rate_lowest_index(sband, sta);
2121                 return;
2122         }
2123
2124         lq_sta = (struct iwl_lq_sta *)priv_sta;
2125         i = 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 ((i < 0) || (i > IWL_RATE_COUNT)) {
2146                 sel->rate_idx = rate_lowest_index(sband, sta);
2147                 return;
2148         }
2149
2150         if (sband->band == IEEE80211_BAND_5GHZ)
2151                 i -= IWL_FIRST_OFDM_RATE;
2152         sel->rate_idx = i;
2153 }
2154
2155 static void *rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2156                           gfp_t gfp)
2157 {
2158         struct iwl_lq_sta *lq_sta;
2159         struct iwl_priv *priv;
2160         int i, j;
2161
2162         priv = (struct iwl_priv *)priv_rate;
2163         IWL_DEBUG_RATE("create station rate scale window\n");
2164
2165         lq_sta = kzalloc(sizeof(struct iwl_lq_sta), gfp);
2166
2167         if (lq_sta == NULL)
2168                 return NULL;
2169         lq_sta->lq.sta_id = 0xff;
2170
2171
2172         for (j = 0; j < LQ_SIZE; j++)
2173                 for (i = 0; i < IWL_RATE_COUNT; i++)
2174                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2175
2176         return lq_sta;
2177 }
2178
2179 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
2180                          struct ieee80211_sta *sta, void *priv_sta)
2181 {
2182         int i, j;
2183         struct iwl_priv *priv = (struct iwl_priv *)priv_r;
2184         struct ieee80211_conf *conf = &priv->hw->conf;
2185         struct iwl_lq_sta *lq_sta = priv_sta;
2186
2187         lq_sta->flush_timer = 0;
2188         lq_sta->supp_rates = sta->supp_rates[sband->band];
2189         for (j = 0; j < LQ_SIZE; j++)
2190                 for (i = 0; i < IWL_RATE_COUNT; i++)
2191                         rs_rate_scale_clear_window(&lq_sta->lq_info[j].win[i]);
2192
2193         IWL_DEBUG_RATE("LQ: *** rate scale station global init ***\n");
2194         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2195          * the lowest or the highest rate.. Could consider using RSSI from
2196          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2197          * after assoc.. */
2198
2199         lq_sta->ibss_sta_added = 0;
2200         if (priv->iw_mode == NL80211_IFTYPE_AP) {
2201                 u8 sta_id = iwl_find_station(priv, sta->addr);
2202
2203                 /* for IBSS the call are from tasklet */
2204                 IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2205
2206                 if (sta_id == IWL_INVALID_STATION) {
2207                         IWL_DEBUG_RATE("LQ: ADD station %pM\n", sta->addr);
2208                         sta_id = iwl_add_station_flags(priv, sta->addr,
2209                                                         0, CMD_ASYNC, NULL);
2210                 }
2211                 if ((sta_id != IWL_INVALID_STATION)) {
2212                         lq_sta->lq.sta_id = sta_id;
2213                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2214                 }
2215                 /* FIXME: this is w/a remove it later */
2216                 priv->assoc_station_added = 1;
2217         }
2218
2219         /* Find highest tx rate supported by hardware and destination station */
2220         lq_sta->last_txrate_idx = 3;
2221         for (i = 0; i < sband->n_bitrates; i++)
2222                 if (sta->supp_rates[sband->band] & BIT(i))
2223                         lq_sta->last_txrate_idx = i;
2224
2225         /* For MODE_IEEE80211A, skip over cck rates in global rate table */
2226         if (sband->band == IEEE80211_BAND_5GHZ)
2227                 lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2228
2229         lq_sta->is_dup = 0;
2230         lq_sta->is_green = rs_use_green(priv, conf);
2231         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2232         lq_sta->active_rate_basic = priv->active_rate_basic;
2233         lq_sta->band = priv->band;
2234         /*
2235          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2236          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2237          */
2238         lq_sta->active_siso_rate = sta->ht_cap.mcs.rx_mask[0] << 1;
2239         lq_sta->active_siso_rate |= sta->ht_cap.mcs.rx_mask[0] & 0x1;
2240         lq_sta->active_siso_rate &= ~((u16)0x2);
2241         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2242
2243         /* Same here */
2244         lq_sta->active_mimo2_rate = sta->ht_cap.mcs.rx_mask[1] << 1;
2245         lq_sta->active_mimo2_rate |= sta->ht_cap.mcs.rx_mask[1] & 0x1;
2246         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2247         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2248
2249         lq_sta->active_mimo3_rate = sta->ht_cap.mcs.rx_mask[2] << 1;
2250         lq_sta->active_mimo3_rate |= sta->ht_cap.mcs.rx_mask[2] & 0x1;
2251         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2252         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2253
2254         IWL_DEBUG_RATE("SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2255                      lq_sta->active_siso_rate,
2256                      lq_sta->active_mimo2_rate,
2257                      lq_sta->active_mimo3_rate);
2258
2259         /* These values will be overriden later */
2260         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2261         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2262
2263         /* as default allow aggregation for all tids */
2264         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2265         lq_sta->drv = priv;
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_clear(void *priv_rate)
2400 {
2401 #ifdef CONFIG_IWLWIFI_DEBUG
2402         struct iwl_priv *priv = (struct iwl_priv *) priv_rate;
2403
2404         IWL_DEBUG_RATE("enter\n");
2405
2406         /* TODO - add rate scale state reset */
2407
2408         IWL_DEBUG_RATE("leave\n");
2409 #endif /* CONFIG_IWLWIFI_DEBUG */
2410 }
2411
2412 static void rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2413                         void *priv_sta)
2414 {
2415         struct iwl_lq_sta *lq_sta = priv_sta;
2416         struct iwl_priv *priv __maybe_unused = priv_r;
2417
2418         IWL_DEBUG_RATE("enter\n");
2419         kfree(lq_sta);
2420         IWL_DEBUG_RATE("leave\n");
2421 }
2422
2423
2424 #ifdef CONFIG_MAC80211_DEBUGFS
2425 static int open_file_generic(struct inode *inode, struct file *file)
2426 {
2427         file->private_data = inode->i_private;
2428         return 0;
2429 }
2430 static void rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2431                              u32 *rate_n_flags, int index)
2432 {
2433         struct iwl_priv *priv;
2434
2435         priv = lq_sta->drv;
2436         if (lq_sta->dbg_fixed_rate) {
2437                 if (index < 12) {
2438                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2439                 } else {
2440                         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2441                                 *rate_n_flags = 0x800D;
2442                         else
2443                                 *rate_n_flags = 0x820A;
2444                 }
2445                 IWL_DEBUG_RATE("Fixed rate ON\n");
2446         } else {
2447                 IWL_DEBUG_RATE("Fixed rate OFF\n");
2448         }
2449 }
2450
2451 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2452                         const char __user *user_buf, size_t count, loff_t *ppos)
2453 {
2454         struct iwl_lq_sta *lq_sta = file->private_data;
2455         struct iwl_priv *priv;
2456         char buf[64];
2457         int buf_size;
2458         u32 parsed_rate;
2459
2460         priv = lq_sta->drv;
2461         memset(buf, 0, sizeof(buf));
2462         buf_size = min(count, sizeof(buf) -  1);
2463         if (copy_from_user(buf, user_buf, buf_size))
2464                 return -EFAULT;
2465
2466         if (sscanf(buf, "%x", &parsed_rate) == 1)
2467                 lq_sta->dbg_fixed_rate = parsed_rate;
2468         else
2469                 lq_sta->dbg_fixed_rate = 0;
2470
2471         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2472         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2473         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2474         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2475
2476         IWL_DEBUG_RATE("sta_id %d rate 0x%X\n",
2477                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2478
2479         if (lq_sta->dbg_fixed_rate) {
2480                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2481                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2482         }
2483
2484         return count;
2485 }
2486
2487 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2488                         char __user *user_buf, size_t count, loff_t *ppos)
2489 {
2490         char buff[1024];
2491         int desc = 0;
2492         int i = 0;
2493
2494         struct iwl_lq_sta *lq_sta = file->private_data;
2495
2496         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2497         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2498                         lq_sta->total_failed, lq_sta->total_success,
2499                         lq_sta->active_legacy_rate);
2500         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2501                         lq_sta->dbg_fixed_rate);
2502         desc += sprintf(buff+desc, "general:"
2503                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2504                 lq_sta->lq.general_params.flags,
2505                 lq_sta->lq.general_params.mimo_delimiter,
2506                 lq_sta->lq.general_params.single_stream_ant_msk,
2507                 lq_sta->lq.general_params.dual_stream_ant_msk);
2508
2509         desc += sprintf(buff+desc, "agg:"
2510                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2511                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2512                         lq_sta->lq.agg_params.agg_dis_start_th,
2513                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2514
2515         desc += sprintf(buff+desc,
2516                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2517                         lq_sta->lq.general_params.start_rate_index[0],
2518                         lq_sta->lq.general_params.start_rate_index[1],
2519                         lq_sta->lq.general_params.start_rate_index[2],
2520                         lq_sta->lq.general_params.start_rate_index[3]);
2521
2522
2523         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2524                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2525                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2526
2527         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2528 }
2529
2530 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2531         .write = rs_sta_dbgfs_scale_table_write,
2532         .read = rs_sta_dbgfs_scale_table_read,
2533         .open = open_file_generic,
2534 };
2535 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2536                         char __user *user_buf, size_t count, loff_t *ppos)
2537 {
2538         char buff[1024];
2539         int desc = 0;
2540         int i, j;
2541
2542         struct iwl_lq_sta *lq_sta = file->private_data;
2543         for (i = 0; i < LQ_SIZE; i++) {
2544                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2545                                 "rate=0x%X\n",
2546                                 lq_sta->active_tbl == i?"*":"x",
2547                                 lq_sta->lq_info[i].lq_type,
2548                                 lq_sta->lq_info[i].is_SGI,
2549                                 lq_sta->lq_info[i].is_fat,
2550                                 lq_sta->lq_info[i].is_dup,
2551                                 lq_sta->lq_info[i].current_rate);
2552                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2553                         desc += sprintf(buff+desc,
2554                                 "counter=%d success=%d %%=%d\n",
2555                                 lq_sta->lq_info[i].win[j].counter,
2556                                 lq_sta->lq_info[i].win[j].success_counter,
2557                                 lq_sta->lq_info[i].win[j].success_ratio);
2558                 }
2559         }
2560         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2561 }
2562
2563 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2564         .read = rs_sta_dbgfs_stats_table_read,
2565         .open = open_file_generic,
2566 };
2567
2568 static void rs_add_debugfs(void *priv, void *priv_sta,
2569                                         struct dentry *dir)
2570 {
2571         struct iwl_lq_sta *lq_sta = priv_sta;
2572         lq_sta->rs_sta_dbgfs_scale_table_file =
2573                 debugfs_create_file("rate_scale_table", 0600, dir,
2574                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2575         lq_sta->rs_sta_dbgfs_stats_table_file =
2576                 debugfs_create_file("rate_stats_table", 0600, dir,
2577                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2578         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2579                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2580                 &lq_sta->tx_agg_tid_en);
2581
2582 }
2583
2584 static void rs_remove_debugfs(void *priv, void *priv_sta)
2585 {
2586         struct iwl_lq_sta *lq_sta = priv_sta;
2587         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2588         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2589         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2590 }
2591 #endif
2592
2593 static struct rate_control_ops rs_ops = {
2594         .module = NULL,
2595         .name = RS_NAME,
2596         .tx_status = rs_tx_status,
2597         .get_rate = rs_get_rate,
2598         .rate_init = rs_rate_init,
2599         .clear = rs_clear,
2600         .alloc = rs_alloc,
2601         .free = rs_free,
2602         .alloc_sta = rs_alloc_sta,
2603         .free_sta = rs_free_sta,
2604 #ifdef CONFIG_MAC80211_DEBUGFS
2605         .add_sta_debugfs = rs_add_debugfs,
2606         .remove_sta_debugfs = rs_remove_debugfs,
2607 #endif
2608 };
2609
2610 int iwlagn_rate_control_register(void)
2611 {
2612         return ieee80211_rate_control_register(&rs_ops);
2613 }
2614
2615 void iwlagn_rate_control_unregister(void)
2616 {
2617         ieee80211_rate_control_unregister(&rs_ops);
2618 }
2619