Merge commit 'upstream/master'
[linux-2.6] / drivers / net / wireless / iwlwifi / iwl-4965-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 "../net/mac80211/rate.h"
39
40 #include "iwl-dev.h"
41 #include "iwl-sta.h"
42 #include "iwl-core.h"
43 #include "iwl-helpers.h"
44
45 #define RS_NAME "iwl-4965-rs"
46
47 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
48 #define IWL_NUMBER_TRY      1
49 #define IWL_HT_NUMBER_TRY   3
50
51 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
52 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
53 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
54
55 /* max time to accum history 2 seconds */
56 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
57
58 static u8 rs_ht_to_legacy[] = {
59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
60         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
61         IWL_RATE_6M_INDEX,
62         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
63         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
64         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
65         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
66 };
67
68 static const u8 ant_toggle_lookup[] = {
69         /*ANT_NONE -> */ ANT_NONE,
70         /*ANT_A    -> */ ANT_B,
71         /*ANT_B    -> */ ANT_C,
72         /*ANT_AB   -> */ ANT_BC,
73         /*ANT_C    -> */ ANT_A,
74         /*ANT_AC   -> */ ANT_AB,
75         /*ANT_BC   -> */ ANT_AC,
76         /*ANT_ABC  -> */ ANT_ABC,
77 };
78
79 /**
80  * struct iwl4965_rate_scale_data -- tx success history for one rate
81  */
82 struct iwl4965_rate_scale_data {
83         u64 data;               /* bitmap of successful frames */
84         s32 success_counter;    /* number of frames successful */
85         s32 success_ratio;      /* per-cent * 128  */
86         s32 counter;            /* number of frames attempted */
87         s32 average_tpt;        /* success ratio * expected throughput */
88         unsigned long stamp;
89 };
90
91 /**
92  * struct iwl4965_scale_tbl_info -- tx params and success history for all rates
93  *
94  * There are two of these in struct iwl4965_lq_sta,
95  * one for "active", and one for "search".
96  */
97 struct iwl4965_scale_tbl_info {
98         enum iwl_table_type lq_type;
99         u8 ant_type;
100         u8 is_SGI;      /* 1 = short guard interval */
101         u8 is_fat;      /* 1 = 40 MHz channel width */
102         u8 is_dup;      /* 1 = duplicated data streams */
103         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
104         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
105         u32 current_rate;  /* rate_n_flags, uCode API format */
106         struct iwl4965_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
107 };
108
109 struct iwl4965_traffic_load {
110         unsigned long time_stamp;       /* age of the oldest statistics */
111         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
112                                                  * slice */
113         u32 total;                      /* total num of packets during the
114                                          * last TID_MAX_TIME_DIFF */
115         u8 queue_count;                 /* number of queues that has
116                                          * been used since the last cleanup */
117         u8 head;                        /* start of the circular buffer */
118 };
119
120 /**
121  * struct iwl4965_lq_sta -- driver's rate scaling private structure
122  *
123  * Pointer to this gets passed back and forth between driver and mac80211.
124  */
125 struct iwl4965_lq_sta {
126         u8 active_tbl;          /* index of active table, range 0-1 */
127         u8 enable_counter;      /* indicates HT mode */
128         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
129         u8 search_better_tbl;   /* 1: currently trying alternate mode */
130         s32 last_tpt;
131
132         /* The following determine when to search for a new mode */
133         u32 table_count_limit;
134         u32 max_failure_limit;  /* # failed frames before new search */
135         u32 max_success_limit;  /* # successful frames before new search */
136         u32 table_count;
137         u32 total_failed;       /* total failed frames, any/all rates */
138         u32 total_success;      /* total successful frames, any/all rates */
139         u32 flush_timer;        /* time staying in mode before new search */
140
141         u8 action_counter;      /* # mode-switch actions tried */
142         u8 is_green;
143         u8 is_dup;
144         enum ieee80211_band band;
145         u8 ibss_sta_added;
146
147         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
148         u32 supp_rates;
149         u16 active_legacy_rate;
150         u16 active_siso_rate;
151         u16 active_mimo2_rate;
152         u16 active_mimo3_rate;
153         u16 active_rate_basic;
154
155         struct iwl_link_quality_cmd lq;
156         struct iwl4965_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
157         struct iwl4965_traffic_load load[TID_MAX_LOAD_COUNT];
158         u8 tx_agg_tid_en;
159 #ifdef CONFIG_MAC80211_DEBUGFS
160         struct dentry *rs_sta_dbgfs_scale_table_file;
161         struct dentry *rs_sta_dbgfs_stats_table_file;
162         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
163         u32 dbg_fixed_rate;
164 #endif
165         struct iwl_priv *drv;
166 };
167
168 static void rs_rate_scale_perform(struct iwl_priv *priv,
169                                    struct net_device *dev,
170                                    struct ieee80211_hdr *hdr,
171                                    struct sta_info *sta);
172 static void rs_fill_link_cmd(const struct iwl_priv *priv,
173                              struct iwl4965_lq_sta *lq_sta,
174                              u32 rate_n_flags);
175
176
177 #ifdef CONFIG_MAC80211_DEBUGFS
178 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
179                                         u32 *rate_n_flags, int index);
180 #else
181 static void rs_dbgfs_set_mcs(struct iwl4965_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 iwl4965_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 iwl4965_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 iwl4965_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 iwl4965_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 iwl4965_lq_sta *lq_data, u8 tid)
329 {
330         u32 curr_time = jiffies_to_msecs(jiffies);
331         u32 time_diff;
332         s32 index;
333         struct iwl4965_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 iwl4965_lq_sta *lq_data, u8 tid,
358                                 struct sta_info *sta)
359 {
360         unsigned long state;
361         DECLARE_MAC_BUF(mac);
362
363         spin_lock_bh(&sta->lock);
364         state = sta->ampdu_mlme.tid_state_tx[tid];
365         spin_unlock_bh(&sta->lock);
366
367         if (state == HT_AGG_STATE_IDLE &&
368             rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
369                 IWL_DEBUG_HT("Starting Tx agg: STA: %s tid: %d\n",
370                                 print_mac(mac, sta->addr), tid);
371                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
372         }
373 }
374
375 static void rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
376                                 struct iwl4965_lq_sta *lq_data,
377                                 struct sta_info *sta)
378 {
379         if ((tid < TID_MAX_LOAD_COUNT))
380                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
381         else if (tid == IWL_AGG_ALL_TID)
382                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
383                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
384 }
385
386 static inline int get_num_of_ant_from_rate(u32 rate_n_flags)
387 {
388         return (!!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
389                 !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
390                 !!(rate_n_flags & RATE_MCS_ANT_C_MSK));
391 }
392
393 /**
394  * rs_collect_tx_data - Update the success/failure sliding window
395  *
396  * We keep a sliding window of the last 62 packets transmitted
397  * at this rate.  window->data contains the bitmask of successful
398  * packets.
399  */
400 static int rs_collect_tx_data(struct iwl4965_rate_scale_data *windows,
401                               int scale_index, s32 tpt, int retries,
402                               int successes)
403 {
404         struct iwl4965_rate_scale_data *window = NULL;
405         static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
406         s32 fail_count;
407
408         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
409                 return -EINVAL;
410
411         /* Select data for current tx bit rate */
412         window = &(windows[scale_index]);
413
414         /*
415          * Keep track of only the latest 62 tx frame attempts in this rate's
416          * history window; anything older isn't really relevant any more.
417          * If we have filled up the sliding window, drop the oldest attempt;
418          * if the oldest attempt (highest bit in bitmap) shows "success",
419          * subtract "1" from the success counter (this is the main reason
420          * we keep these bitmaps!).
421          */
422         while (retries > 0) {
423                 if (window->counter >= IWL_RATE_MAX_WINDOW) {
424
425                         /* remove earliest */
426                         window->counter = IWL_RATE_MAX_WINDOW - 1;
427
428                         if (window->data & mask) {
429                                 window->data &= ~mask;
430                                 window->success_counter--;
431                         }
432                 }
433
434                 /* Increment frames-attempted counter */
435                 window->counter++;
436
437                 /* Shift bitmap by one frame (throw away oldest history),
438                  * OR in "1", and increment "success" if this
439                  * frame was successful. */
440                 window->data <<= 1;;
441                 if (successes > 0) {
442                         window->success_counter++;
443                         window->data |= 0x1;
444                         successes--;
445                 }
446
447                 retries--;
448         }
449
450         /* Calculate current success ratio, avoid divide-by-0! */
451         if (window->counter > 0)
452                 window->success_ratio = 128 * (100 * window->success_counter)
453                                         / window->counter;
454         else
455                 window->success_ratio = IWL_INVALID_VALUE;
456
457         fail_count = window->counter - window->success_counter;
458
459         /* Calculate average throughput, if we have enough history. */
460         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
461             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
462                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
463         else
464                 window->average_tpt = IWL_INVALID_VALUE;
465
466         /* Tag this window as having been updated */
467         window->stamp = jiffies;
468
469         return 0;
470 }
471
472 /*
473  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
474  */
475 /* FIXME:RS:remove this function and put the flags statically in the table */
476 static u32 rate_n_flags_from_tbl(struct iwl4965_scale_tbl_info *tbl,
477                                        int index, u8 use_green)
478 {
479         u32 rate_n_flags = 0;
480
481         if (is_legacy(tbl->lq_type)) {
482                 rate_n_flags = iwl_rates[index].plcp;
483                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
484                         rate_n_flags |= RATE_MCS_CCK_MSK;
485
486         } else if (is_Ht(tbl->lq_type)) {
487                 if (index > IWL_LAST_OFDM_RATE) {
488                         IWL_ERROR("invalid HT rate index %d\n", index);
489                         index = IWL_LAST_OFDM_RATE;
490                 }
491                 rate_n_flags = RATE_MCS_HT_MSK;
492
493                 if (is_siso(tbl->lq_type))
494                         rate_n_flags |= iwl_rates[index].plcp_siso;
495                 else if (is_mimo2(tbl->lq_type))
496                         rate_n_flags |= iwl_rates[index].plcp_mimo2;
497                 else
498                         rate_n_flags |= iwl_rates[index].plcp_mimo3;
499         } else {
500                 IWL_ERROR("Invalid tbl->lq_type %d\n", tbl->lq_type);
501         }
502
503         rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
504                                                      RATE_MCS_ANT_ABC_MSK);
505
506         if (is_Ht(tbl->lq_type)) {
507                 if (tbl->is_fat) {
508                         if (tbl->is_dup)
509                                 rate_n_flags |= RATE_MCS_DUP_MSK;
510                         else
511                                 rate_n_flags |= RATE_MCS_FAT_MSK;
512                 }
513                 if (tbl->is_SGI)
514                         rate_n_flags |= RATE_MCS_SGI_MSK;
515
516                 if (use_green) {
517                         rate_n_flags |= RATE_MCS_GF_MSK;
518                         if (is_siso(tbl->lq_type) && tbl->is_SGI) {
519                                 rate_n_flags &= ~RATE_MCS_SGI_MSK;
520                                 IWL_ERROR("GF was set with SGI:SISO\n");
521                         }
522                 }
523         }
524         return rate_n_flags;
525 }
526
527 /*
528  * Interpret uCode API's rate_n_flags format,
529  * fill "search" or "active" tx mode table.
530  */
531 static int rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
532                                     enum ieee80211_band band,
533                                     struct iwl4965_scale_tbl_info *tbl,
534                                     int *rate_idx)
535 {
536         u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
537         u8 num_of_ant = get_num_of_ant_from_rate(rate_n_flags);
538         u8 mcs;
539
540         *rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
541
542         if (*rate_idx  == IWL_RATE_INVALID) {
543                 *rate_idx = -1;
544                 return -EINVAL;
545         }
546         tbl->is_SGI = 0;        /* default legacy setup */
547         tbl->is_fat = 0;
548         tbl->is_dup = 0;
549         tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
550         tbl->lq_type = LQ_NONE;
551
552         /* legacy rate format */
553         if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
554                 if (num_of_ant == 1) {
555                         if (band == IEEE80211_BAND_5GHZ)
556                                 tbl->lq_type = LQ_A;
557                         else
558                                 tbl->lq_type = LQ_G;
559                 }
560         /* HT rate format */
561         } else {
562                 if (rate_n_flags & RATE_MCS_SGI_MSK)
563                         tbl->is_SGI = 1;
564
565                 if ((rate_n_flags & RATE_MCS_FAT_MSK) ||
566                     (rate_n_flags & RATE_MCS_DUP_MSK))
567                         tbl->is_fat = 1;
568
569                 if (rate_n_flags & RATE_MCS_DUP_MSK)
570                         tbl->is_dup = 1;
571
572                 mcs = rs_extract_rate(rate_n_flags);
573
574                 /* SISO */
575                 if (mcs <= IWL_RATE_SISO_60M_PLCP) {
576                         if (num_of_ant == 1)
577                                 tbl->lq_type = LQ_SISO; /*else NONE*/
578                 /* MIMO2 */
579                 } else if (mcs <= IWL_RATE_MIMO2_60M_PLCP) {
580                         if (num_of_ant == 2)
581                                 tbl->lq_type = LQ_MIMO2;
582                 /* MIMO3 */
583                 } else {
584                         if (num_of_ant == 3)
585                                 tbl->lq_type = LQ_MIMO3;
586                 }
587         }
588         return 0;
589 }
590
591 /* switch to another antenna/antennas and return 1 */
592 /* if no other valid antenna found, return 0 */
593 static int rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
594                               struct iwl4965_scale_tbl_info *tbl)
595 {
596         u8 new_ant_type;
597
598         if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
599                 return 0;
600
601         if (!rs_is_valid_ant(valid_ant, tbl->ant_type))
602                 return 0;
603
604         new_ant_type = ant_toggle_lookup[tbl->ant_type];
605
606         while ((new_ant_type != tbl->ant_type) &&
607                !rs_is_valid_ant(valid_ant, new_ant_type))
608                 new_ant_type = ant_toggle_lookup[new_ant_type];
609
610         if (new_ant_type == tbl->ant_type)
611                 return 0;
612
613         tbl->ant_type = new_ant_type;
614         *rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
615         *rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
616         return 1;
617 }
618
619 /* FIXME:RS: in 4965 we don't use greenfield at all */
620 /* FIXME:RS: don't use greenfield for now in TX */
621 #if 0
622 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
623 {
624         return ((conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
625                 priv->current_ht_config.is_green_field &&
626                 !priv->current_ht_config.non_GF_STA_present);
627 }
628 #endif
629 static inline u8 rs_use_green(struct iwl_priv *priv, struct ieee80211_conf *conf)
630 {
631         return 0;
632 }
633
634 /**
635  * rs_get_supported_rates - get the available rates
636  *
637  * if management frame or broadcast frame only return
638  * basic available rates.
639  *
640  */
641 static u16 rs_get_supported_rates(struct iwl4965_lq_sta *lq_sta,
642                                    struct ieee80211_hdr *hdr,
643                                    enum iwl_table_type rate_type)
644 {
645         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
646             lq_sta->active_rate_basic)
647                 return lq_sta->active_rate_basic;
648
649         if (is_legacy(rate_type)) {
650                 return lq_sta->active_legacy_rate;
651         } else {
652                 if (is_siso(rate_type))
653                         return lq_sta->active_siso_rate;
654                 else if (is_mimo2(rate_type))
655                         return lq_sta->active_mimo2_rate;
656                 else
657                         return lq_sta->active_mimo3_rate;
658         }
659 }
660
661 static u16 rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
662                                 int rate_type)
663 {
664         u8 high = IWL_RATE_INVALID;
665         u8 low = IWL_RATE_INVALID;
666
667         /* 802.11A or ht walks to the next literal adjacent rate in
668          * the rate table */
669         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
670                 int i;
671                 u32 mask;
672
673                 /* Find the previous rate that is in the rate mask */
674                 i = index - 1;
675                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
676                         if (rate_mask & mask) {
677                                 low = i;
678                                 break;
679                         }
680                 }
681
682                 /* Find the next rate that is in the rate mask */
683                 i = index + 1;
684                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
685                         if (rate_mask & mask) {
686                                 high = i;
687                                 break;
688                         }
689                 }
690
691                 return (high << 8) | low;
692         }
693
694         low = index;
695         while (low != IWL_RATE_INVALID) {
696                 low = iwl_rates[low].prev_rs;
697                 if (low == IWL_RATE_INVALID)
698                         break;
699                 if (rate_mask & (1 << low))
700                         break;
701                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
702         }
703
704         high = index;
705         while (high != IWL_RATE_INVALID) {
706                 high = iwl_rates[high].next_rs;
707                 if (high == IWL_RATE_INVALID)
708                         break;
709                 if (rate_mask & (1 << high))
710                         break;
711                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
712         }
713
714         return (high << 8) | low;
715 }
716
717 static u32 rs_get_lower_rate(struct iwl4965_lq_sta *lq_sta,
718                              struct iwl4965_scale_tbl_info *tbl, u8 scale_index,
719                              u8 ht_possible)
720 {
721         s32 low;
722         u16 rate_mask;
723         u16 high_low;
724         u8 switch_to_legacy = 0;
725         u8 is_green = lq_sta->is_green;
726
727         /* check if we need to switch from HT to legacy rates.
728          * assumption is that mandatory rates (1Mbps or 6Mbps)
729          * are always supported (spec demand) */
730         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
731                 switch_to_legacy = 1;
732                 scale_index = rs_ht_to_legacy[scale_index];
733                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
734                         tbl->lq_type = LQ_A;
735                 else
736                         tbl->lq_type = LQ_G;
737
738                 if (num_of_ant(tbl->ant_type) > 1)
739                         tbl->ant_type = ANT_A;/*FIXME:RS*/
740
741                 tbl->is_fat = 0;
742                 tbl->is_SGI = 0;
743         }
744
745         rate_mask = rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
746
747         /* Mask with station rate restriction */
748         if (is_legacy(tbl->lq_type)) {
749                 /* supp_rates has no CCK bits in A mode */
750                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
751                         rate_mask  = (u16)(rate_mask &
752                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
753                 else
754                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
755         }
756
757         /* If we switched from HT to legacy, check current rate */
758         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
759                 low = scale_index;
760                 goto out;
761         }
762
763         high_low = rs_get_adjacent_rate(lq_sta->drv, scale_index, rate_mask,
764                                         tbl->lq_type);
765         low = high_low & 0xff;
766
767         if (low == IWL_RATE_INVALID)
768                 low = scale_index;
769
770 out:
771         return rate_n_flags_from_tbl(tbl, low, is_green);
772 }
773
774 /*
775  * mac80211 sends us Tx status
776  */
777 static void rs_tx_status(void *priv_rate, struct net_device *dev,
778                          struct sk_buff *skb)
779 {
780         int status;
781         u8 retries;
782         int rs_index, index = 0;
783         struct iwl4965_lq_sta *lq_sta;
784         struct iwl_link_quality_cmd *table;
785         struct sta_info *sta;
786         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
787         struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
788         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
789         struct ieee80211_hw *hw = local_to_hw(local);
790         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
791         struct iwl4965_rate_scale_data *window = NULL;
792         struct iwl4965_rate_scale_data *search_win = NULL;
793         u32 tx_rate;
794         struct iwl4965_scale_tbl_info tbl_type;
795         struct iwl4965_scale_tbl_info *curr_tbl, *search_tbl;
796         u8 active_index = 0;
797         __le16 fc = hdr->frame_control;
798         s32 tpt = 0;
799
800         IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
801
802         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1))
803                 return;
804
805         /* This packet was aggregated but doesn't carry rate scale info */
806         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
807             !(info->flags & IEEE80211_TX_STAT_AMPDU))
808                 return;
809
810         retries = info->status.retry_count;
811
812         if (retries > 15)
813                 retries = 15;
814
815         rcu_read_lock();
816
817         sta = sta_info_get(local, hdr->addr1);
818
819         if (!sta || !sta->rate_ctrl_priv)
820                 goto out;
821
822
823         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
824
825         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
826             !lq_sta->ibss_sta_added)
827                 goto out;
828
829         table = &lq_sta->lq;
830         active_index = lq_sta->active_tbl;
831
832         curr_tbl = &(lq_sta->lq_info[active_index]);
833         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
834         window = (struct iwl4965_rate_scale_data *)
835             &(curr_tbl->win[0]);
836         search_win = (struct iwl4965_rate_scale_data *)
837             &(search_tbl->win[0]);
838
839         /*
840          * Ignore this Tx frame response if its initial rate doesn't match
841          * that of latest Link Quality command.  There may be stragglers
842          * from a previous Link Quality command, but we're no longer interested
843          * in those; they're either from the "active" mode while we're trying
844          * to check "search" mode, or a prior "search" mode after we've moved
845          * to a new "search" mode (which might become the new "active" mode).
846          */
847         tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
848         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
849         if (priv->band == IEEE80211_BAND_5GHZ)
850                 rs_index -= IWL_FIRST_OFDM_RATE;
851
852         if ((info->tx_rate_idx < 0) ||
853             (tbl_type.is_SGI ^
854                 !!(info->flags & IEEE80211_TX_CTL_SHORT_GI)) ||
855             (tbl_type.is_fat ^
856                 !!(info->flags & IEEE80211_TX_CTL_40_MHZ_WIDTH)) ||
857             (tbl_type.is_dup ^
858                 !!(info->flags & IEEE80211_TX_CTL_DUP_DATA)) ||
859             (tbl_type.ant_type ^ info->antenna_sel_tx) ||
860             (!!(tx_rate & RATE_MCS_HT_MSK) ^
861                 !!(info->flags & IEEE80211_TX_CTL_OFDM_HT)) ||
862             (!!(tx_rate & RATE_MCS_GF_MSK) ^
863                 !!(info->flags & IEEE80211_TX_CTL_GREEN_FIELD)) ||
864             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
865              hw->wiphy->bands[info->band]->bitrates[info->tx_rate_idx].bitrate)) {
866                 IWL_DEBUG_RATE("initial rate does not match 0x%x\n", tx_rate);
867                 goto out;
868         }
869
870         /* Update frame history window with "failure" for each Tx retry. */
871         while (retries) {
872                 /* Look up the rate and other info used for each tx attempt.
873                  * Each tx attempt steps one entry deeper in the rate table. */
874                 tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
875                 rs_get_tbl_info_from_mcs(tx_rate, priv->band,
876                                           &tbl_type, &rs_index);
877
878                 /* If type matches "search" table,
879                  * add failure to "search" history */
880                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
881                     (tbl_type.ant_type == search_tbl->ant_type) &&
882                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
883                         if (search_tbl->expected_tpt)
884                                 tpt = search_tbl->expected_tpt[rs_index];
885                         else
886                                 tpt = 0;
887                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
888
889                 /* Else if type matches "current/active" table,
890                  * add failure to "current/active" history */
891                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
892                            (tbl_type.ant_type == curr_tbl->ant_type) &&
893                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
894                         if (curr_tbl->expected_tpt)
895                                 tpt = curr_tbl->expected_tpt[rs_index];
896                         else
897                                 tpt = 0;
898                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
899                 }
900
901                 /* If not searching for a new mode, increment failed counter
902                  * ... this helps determine when to start searching again */
903                 if (lq_sta->stay_in_tbl)
904                         lq_sta->total_failed++;
905                 --retries;
906                 index++;
907
908         }
909
910         /*
911          * Find (by rate) the history window to update with final Tx attempt;
912          * if Tx was successful first try, use original rate,
913          * else look up the rate that was, finally, successful.
914          */
915         tx_rate = le32_to_cpu(table->rs_table[index].rate_n_flags);
916         rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type, &rs_index);
917
918         /* Update frame history window with "success" if Tx got ACKed ... */
919         status = !!(info->flags & IEEE80211_TX_STAT_ACK);
920
921         /* If type matches "search" table,
922          * add final tx status to "search" history */
923         if ((tbl_type.lq_type == search_tbl->lq_type) &&
924             (tbl_type.ant_type == search_tbl->ant_type) &&
925             (tbl_type.is_SGI == search_tbl->is_SGI)) {
926                 if (search_tbl->expected_tpt)
927                         tpt = search_tbl->expected_tpt[rs_index];
928                 else
929                         tpt = 0;
930                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
931                         rs_collect_tx_data(search_win, rs_index, tpt,
932                                            info->status.ampdu_ack_len,
933                                            info->status.ampdu_ack_map);
934                 else
935                         rs_collect_tx_data(search_win, rs_index, tpt,
936                                            1, status);
937         /* Else if type matches "current/active" table,
938          * add final tx status to "current/active" history */
939         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
940                    (tbl_type.ant_type == curr_tbl->ant_type) &&
941                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
942                 if (curr_tbl->expected_tpt)
943                         tpt = curr_tbl->expected_tpt[rs_index];
944                 else
945                         tpt = 0;
946                 if (info->flags & IEEE80211_TX_CTL_AMPDU)
947                         rs_collect_tx_data(window, rs_index, tpt,
948                                            info->status.ampdu_ack_len,
949                                            info->status.ampdu_ack_map);
950                 else
951                         rs_collect_tx_data(window, rs_index, tpt,
952                                            1, status);
953         }
954
955         /* If not searching for new mode, increment success/failed counter
956          * ... these help determine when to start searching again */
957         if (lq_sta->stay_in_tbl) {
958                 if (info->flags & IEEE80211_TX_CTL_AMPDU) {
959                         lq_sta->total_success += info->status.ampdu_ack_map;
960                         lq_sta->total_failed +=
961                              (info->status.ampdu_ack_len - info->status.ampdu_ack_map);
962                 } else {
963                         if (status)
964                                 lq_sta->total_success++;
965                         else
966                                 lq_sta->total_failed++;
967                 }
968         }
969
970         /* See if there's a better rate or modulation mode to try. */
971         rs_rate_scale_perform(priv, dev, hdr, sta);
972 out:
973         rcu_read_unlock();
974         return;
975 }
976
977 /*
978  * Begin a period of staying with a selected modulation mode.
979  * Set "stay_in_tbl" flag to prevent any mode switches.
980  * Set frame tx success limits according to legacy vs. high-throughput,
981  * and reset overall (spanning all rates) tx success history statistics.
982  * These control how long we stay using same modulation mode before
983  * searching for a new mode.
984  */
985 static void rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
986                                  struct iwl4965_lq_sta *lq_sta)
987 {
988         IWL_DEBUG_RATE("we are staying in the same table\n");
989         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
990         if (is_legacy) {
991                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
992                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
993                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
994         } else {
995                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
996                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
997                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
998         }
999         lq_sta->table_count = 0;
1000         lq_sta->total_failed = 0;
1001         lq_sta->total_success = 0;
1002 }
1003
1004 /*
1005  * Find correct throughput table for given mode of modulation
1006  */
1007 static void rs_set_expected_tpt_table(struct iwl4965_lq_sta *lq_sta,
1008                                       struct iwl4965_scale_tbl_info *tbl)
1009 {
1010         if (is_legacy(tbl->lq_type)) {
1011                 if (!is_a_band(tbl->lq_type))
1012                         tbl->expected_tpt = expected_tpt_G;
1013                 else
1014                         tbl->expected_tpt = expected_tpt_A;
1015         } else if (is_siso(tbl->lq_type)) {
1016                 if (tbl->is_fat && !lq_sta->is_dup)
1017                         if (tbl->is_SGI)
1018                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
1019                         else
1020                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1021                 else if (tbl->is_SGI)
1022                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1023                 else
1024                         tbl->expected_tpt = expected_tpt_siso20MHz;
1025
1026         } else if (is_mimo(tbl->lq_type)) { /* FIXME:need to separate mimo2/3 */
1027                 if (tbl->is_fat && !lq_sta->is_dup)
1028                         if (tbl->is_SGI)
1029                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
1030                         else
1031                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
1032                 else if (tbl->is_SGI)
1033                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
1034                 else
1035                         tbl->expected_tpt = expected_tpt_mimo20MHz;
1036         } else
1037                 tbl->expected_tpt = expected_tpt_G;
1038 }
1039
1040 /*
1041  * Find starting rate for new "search" high-throughput mode of modulation.
1042  * Goal is to find lowest expected rate (under perfect conditions) that is
1043  * above the current measured throughput of "active" mode, to give new mode
1044  * a fair chance to prove itself without too many challenges.
1045  *
1046  * This gets called when transitioning to more aggressive modulation
1047  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1048  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1049  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1050  * bit rate will typically need to increase, but not if performance was bad.
1051  */
1052 static s32 rs_get_best_rate(struct iwl_priv *priv,
1053                             struct iwl4965_lq_sta *lq_sta,
1054                             struct iwl4965_scale_tbl_info *tbl, /* "search" */
1055                             u16 rate_mask, s8 index)
1056 {
1057         /* "active" values */
1058         struct iwl4965_scale_tbl_info *active_tbl =
1059             &(lq_sta->lq_info[lq_sta->active_tbl]);
1060         s32 active_sr = active_tbl->win[index].success_ratio;
1061         s32 active_tpt = active_tbl->expected_tpt[index];
1062
1063         /* expected "search" throughput */
1064         s32 *tpt_tbl = tbl->expected_tpt;
1065
1066         s32 new_rate, high, low, start_hi;
1067         u16 high_low;
1068         s8 rate = index;
1069
1070         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1071
1072         for (; ;) {
1073                 high_low = rs_get_adjacent_rate(priv, rate, rate_mask,
1074                                                 tbl->lq_type);
1075
1076                 low = high_low & 0xff;
1077                 high = (high_low >> 8) & 0xff;
1078
1079                 /*
1080                  * Lower the "search" bit rate, to give new "search" mode
1081                  * approximately the same throughput as "active" if:
1082                  *
1083                  * 1) "Active" mode has been working modestly well (but not
1084                  *    great), and expected "search" throughput (under perfect
1085                  *    conditions) at candidate rate is above the actual
1086                  *    measured "active" throughput (but less than expected
1087                  *    "active" throughput under perfect conditions).
1088                  * OR
1089                  * 2) "Active" mode has been working perfectly or very well
1090                  *    and expected "search" throughput (under perfect
1091                  *    conditions) at candidate rate is above expected
1092                  *    "active" throughput (under perfect conditions).
1093                  */
1094                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1095                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1096                       (active_sr <= IWL_RATE_HIGH_TH) &&
1097                       (tpt_tbl[rate] <= active_tpt))) ||
1098                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1099                      (tpt_tbl[rate] > active_tpt))) {
1100
1101                         /* (2nd or later pass)
1102                          * If we've already tried to raise the rate, and are
1103                          * now trying to lower it, use the higher rate. */
1104                         if (start_hi != IWL_RATE_INVALID) {
1105                                 new_rate = start_hi;
1106                                 break;
1107                         }
1108
1109                         new_rate = rate;
1110
1111                         /* Loop again with lower rate */
1112                         if (low != IWL_RATE_INVALID)
1113                                 rate = low;
1114
1115                         /* Lower rate not available, use the original */
1116                         else
1117                                 break;
1118
1119                 /* Else try to raise the "search" rate to match "active" */
1120                 } else {
1121                         /* (2nd or later pass)
1122                          * If we've already tried to lower the rate, and are
1123                          * now trying to raise it, use the lower rate. */
1124                         if (new_rate != IWL_RATE_INVALID)
1125                                 break;
1126
1127                         /* Loop again with higher rate */
1128                         else if (high != IWL_RATE_INVALID) {
1129                                 start_hi = high;
1130                                 rate = high;
1131
1132                         /* Higher rate not available, use the original */
1133                         } else {
1134                                 break;
1135                         }
1136                 }
1137         }
1138
1139         return new_rate;
1140 }
1141
1142 /*
1143  * Set up search table for MIMO
1144  */
1145 static int rs_switch_to_mimo2(struct iwl_priv *priv,
1146                              struct iwl4965_lq_sta *lq_sta,
1147                              struct ieee80211_conf *conf,
1148                              struct sta_info *sta,
1149                              struct iwl4965_scale_tbl_info *tbl, int index)
1150 {
1151         u16 rate_mask;
1152         s32 rate;
1153         s8 is_green = lq_sta->is_green;
1154
1155         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1156             !sta->ht_info.ht_supported)
1157                 return -1;
1158
1159         if (priv->current_ht_config.tx_mimo_ps_mode == IWL_MIMO_PS_STATIC)
1160                 return -1;
1161
1162         /* Need both Tx chains/antennas to support MIMO */
1163         if (priv->hw_params.tx_chains_num < 2)
1164                 return -1;
1165
1166         IWL_DEBUG_RATE("LQ: try to switch to MIMO2\n");
1167
1168         tbl->lq_type = LQ_MIMO2;
1169         tbl->is_dup = lq_sta->is_dup;
1170         tbl->action = 0;
1171         rate_mask = lq_sta->active_mimo2_rate;
1172
1173         if (priv->current_ht_config.supported_chan_width
1174                                         == IWL_CHANNEL_WIDTH_40MHZ)
1175                 tbl->is_fat = 1;
1176         else
1177                 tbl->is_fat = 0;
1178
1179         /* FIXME: - don't toggle SGI here
1180         if (tbl->is_fat) {
1181                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1182                         tbl->is_SGI = 1;
1183                 else
1184                         tbl->is_SGI = 0;
1185         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1186                 tbl->is_SGI = 1;
1187         else
1188                 tbl->is_SGI = 0;
1189         */
1190
1191         rs_set_expected_tpt_table(lq_sta, tbl);
1192
1193         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1194
1195         IWL_DEBUG_RATE("LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1196
1197         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1198                 IWL_DEBUG_RATE("Can't switch with index %d rate mask %x\n",
1199                                                 rate, rate_mask);
1200                 return -1;
1201         }
1202         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1203
1204         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1205                      tbl->current_rate, is_green);
1206         return 0;
1207 }
1208
1209 /*
1210  * Set up search table for SISO
1211  */
1212 static int rs_switch_to_siso(struct iwl_priv *priv,
1213                              struct iwl4965_lq_sta *lq_sta,
1214                              struct ieee80211_conf *conf,
1215                              struct sta_info *sta,
1216                              struct iwl4965_scale_tbl_info *tbl, int index)
1217 {
1218         u16 rate_mask;
1219         u8 is_green = lq_sta->is_green;
1220         s32 rate;
1221
1222         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1223             !sta->ht_info.ht_supported)
1224                 return -1;
1225
1226         IWL_DEBUG_RATE("LQ: try to switch to SISO\n");
1227
1228         tbl->is_dup = lq_sta->is_dup;
1229         tbl->lq_type = LQ_SISO;
1230         tbl->action = 0;
1231         rate_mask = lq_sta->active_siso_rate;
1232
1233         if (priv->current_ht_config.supported_chan_width
1234             == IWL_CHANNEL_WIDTH_40MHZ)
1235                 tbl->is_fat = 1;
1236         else
1237                 tbl->is_fat = 0;
1238
1239         /* FIXME: - don't toggle SGI here
1240         if (tbl->is_fat) {
1241                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1242                         tbl->is_SGI = 1;
1243                 else
1244                         tbl->is_SGI = 0;
1245         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1246                 tbl->is_SGI = 1;
1247         else
1248                 tbl->is_SGI = 0;
1249         */
1250
1251         if (is_green)
1252                 tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1253
1254         rs_set_expected_tpt_table(lq_sta, tbl);
1255         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1256
1257         IWL_DEBUG_RATE("LQ: get best rate %d mask %X\n", rate, rate_mask);
1258         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1259                 IWL_DEBUG_RATE("can not switch with index %d rate mask %x\n",
1260                              rate, rate_mask);
1261                 return -1;
1262         }
1263         tbl->current_rate = rate_n_flags_from_tbl(tbl, rate, is_green);
1264         IWL_DEBUG_RATE("LQ: Switch to new mcs %X index is green %X\n",
1265                      tbl->current_rate, is_green);
1266         return 0;
1267 }
1268
1269 /*
1270  * Try to switch to new modulation mode from legacy
1271  */
1272 static int rs_move_legacy_other(struct iwl_priv *priv,
1273                                 struct iwl4965_lq_sta *lq_sta,
1274                                 struct ieee80211_conf *conf,
1275                                 struct sta_info *sta,
1276                                 int index)
1277 {
1278         struct iwl4965_scale_tbl_info *tbl =
1279             &(lq_sta->lq_info[lq_sta->active_tbl]);
1280         struct iwl4965_scale_tbl_info *search_tbl =
1281             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1282         struct iwl4965_rate_scale_data *window = &(tbl->win[index]);
1283         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1284                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1285         u8 start_action = tbl->action;
1286         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1287         int ret = 0;
1288
1289         for (; ;) {
1290                 switch (tbl->action) {
1291                 case IWL_LEGACY_SWITCH_ANTENNA:
1292                         IWL_DEBUG_RATE("LQ: Legacy toggle Antenna\n");
1293
1294                         lq_sta->action_counter++;
1295
1296                         /* Don't change antenna if success has been great */
1297                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1298                                 break;
1299
1300                         /* Set up search table to try other antenna */
1301                         memcpy(search_tbl, tbl, sz);
1302
1303                         if (rs_toggle_antenna(valid_tx_ant,
1304                                 &search_tbl->current_rate, search_tbl)) {
1305                                 lq_sta->search_better_tbl = 1;
1306                                 goto out;
1307                         }
1308                         break;
1309                 case IWL_LEGACY_SWITCH_SISO:
1310                         IWL_DEBUG_RATE("LQ: Legacy switch to SISO\n");
1311
1312                         /* Set up search table to try SISO */
1313                         memcpy(search_tbl, tbl, sz);
1314                         search_tbl->is_SGI = 0;
1315                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1316                                                  search_tbl, index);
1317                         if (!ret) {
1318                                 lq_sta->search_better_tbl = 1;
1319                                 lq_sta->action_counter = 0;
1320                                 goto out;
1321                         }
1322
1323                         break;
1324                 case IWL_LEGACY_SWITCH_MIMO2:
1325                         IWL_DEBUG_RATE("LQ: Legacy switch to MIMO2\n");
1326
1327                         /* Set up search table to try MIMO */
1328                         memcpy(search_tbl, tbl, sz);
1329                         search_tbl->is_SGI = 0;
1330                         search_tbl->ant_type = ANT_AB;/*FIXME:RS*/
1331                                 /*FIXME:RS:need to check ant validity*/
1332                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1333                                                  search_tbl, index);
1334                         if (!ret) {
1335                                 lq_sta->search_better_tbl = 1;
1336                                 lq_sta->action_counter = 0;
1337                                 goto out;
1338                         }
1339                         break;
1340                 }
1341                 tbl->action++;
1342                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO2)
1343                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA;
1344
1345                 if (tbl->action == start_action)
1346                         break;
1347
1348         }
1349         return 0;
1350
1351  out:
1352         tbl->action++;
1353         if (tbl->action > IWL_LEGACY_SWITCH_MIMO2)
1354                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA;
1355         return 0;
1356
1357 }
1358
1359 /*
1360  * Try to switch to new modulation mode from SISO
1361  */
1362 static int rs_move_siso_to_other(struct iwl_priv *priv,
1363                                  struct iwl4965_lq_sta *lq_sta,
1364                                  struct ieee80211_conf *conf,
1365                                  struct sta_info *sta,
1366                                  int index)
1367 {
1368         u8 is_green = lq_sta->is_green;
1369         struct iwl4965_scale_tbl_info *tbl =
1370             &(lq_sta->lq_info[lq_sta->active_tbl]);
1371         struct iwl4965_scale_tbl_info *search_tbl =
1372             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1373         struct iwl4965_rate_scale_data *window = &(tbl->win[index]);
1374         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1375                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1376         u8 start_action = tbl->action;
1377         u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1378         int ret;
1379
1380         for (;;) {
1381                 lq_sta->action_counter++;
1382                 switch (tbl->action) {
1383                 case IWL_SISO_SWITCH_ANTENNA:
1384                         IWL_DEBUG_RATE("LQ: SISO toggle Antenna\n");
1385                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1386                                 break;
1387
1388                         memcpy(search_tbl, tbl, sz);
1389                         if (rs_toggle_antenna(valid_tx_ant,
1390                                        &search_tbl->current_rate, search_tbl)) {
1391                                 lq_sta->search_better_tbl = 1;
1392                                 goto out;
1393                         }
1394                         break;
1395                 case IWL_SISO_SWITCH_MIMO2:
1396                         IWL_DEBUG_RATE("LQ: SISO switch to MIMO2\n");
1397                         memcpy(search_tbl, tbl, sz);
1398                         search_tbl->is_SGI = 0;
1399                         search_tbl->ant_type = ANT_AB; /*FIXME:RS*/
1400                         ret = rs_switch_to_mimo2(priv, lq_sta, conf, sta,
1401                                                  search_tbl, index);
1402                         if (!ret) {
1403                                 lq_sta->search_better_tbl = 1;
1404                                 goto out;
1405                         }
1406                         break;
1407                 case IWL_SISO_SWITCH_GI:
1408                         if (!tbl->is_fat &&
1409                                 !(priv->current_ht_config.sgf &
1410                                                 HT_SHORT_GI_20MHZ))
1411                                 break;
1412                         if (tbl->is_fat &&
1413                                 !(priv->current_ht_config.sgf &
1414                                                 HT_SHORT_GI_40MHZ))
1415                                 break;
1416
1417                         IWL_DEBUG_RATE("LQ: SISO toggle SGI/NGI\n");
1418
1419                         memcpy(search_tbl, tbl, sz);
1420                         if (is_green) {
1421                                 if (!tbl->is_SGI)
1422                                         break;
1423                                 else
1424                                         IWL_ERROR("SGI was set in GF+SISO\n");
1425                         }
1426                         search_tbl->is_SGI = !tbl->is_SGI;
1427                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1428                         if (tbl->is_SGI) {
1429                                 s32 tpt = lq_sta->last_tpt / 100;
1430                                 if (tpt >= search_tbl->expected_tpt[index])
1431                                         break;
1432                         }
1433                         search_tbl->current_rate = rate_n_flags_from_tbl(
1434                                                 search_tbl, index, is_green);
1435                         lq_sta->search_better_tbl = 1;
1436                         goto out;
1437                 }
1438                 tbl->action++;
1439                 if (tbl->action > IWL_SISO_SWITCH_GI)
1440                         tbl->action = IWL_SISO_SWITCH_ANTENNA;
1441
1442                 if (tbl->action == start_action)
1443                         break;
1444         }
1445         return 0;
1446
1447  out:
1448         tbl->action++;
1449         if (tbl->action > IWL_SISO_SWITCH_GI)
1450                 tbl->action = IWL_SISO_SWITCH_ANTENNA;
1451         return 0;
1452 }
1453
1454 /*
1455  * Try to switch to new modulation mode from MIMO
1456  */
1457 static int rs_move_mimo_to_other(struct iwl_priv *priv,
1458                                  struct iwl4965_lq_sta *lq_sta,
1459                                  struct ieee80211_conf *conf,
1460                                  struct sta_info *sta,
1461                                  int index)
1462 {
1463         s8 is_green = lq_sta->is_green;
1464         struct iwl4965_scale_tbl_info *tbl =
1465             &(lq_sta->lq_info[lq_sta->active_tbl]);
1466         struct iwl4965_scale_tbl_info *search_tbl =
1467             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1468         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1469                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1470         u8 start_action = tbl->action;
1471         /*u8 valid_tx_ant = priv->hw_params.valid_tx_ant;*/
1472         int ret;
1473
1474         for (;;) {
1475                 lq_sta->action_counter++;
1476                 switch (tbl->action) {
1477                 case IWL_MIMO_SWITCH_ANTENNA_A:
1478                 case IWL_MIMO_SWITCH_ANTENNA_B:
1479                         IWL_DEBUG_RATE("LQ: MIMO2 switch to SISO\n");
1480
1481                         /* Set up new search table for SISO */
1482                         memcpy(search_tbl, tbl, sz);
1483
1484                         /*FIXME:RS:need to check ant validity + C*/
1485                         if (tbl->action == IWL_MIMO_SWITCH_ANTENNA_A)
1486                                 search_tbl->ant_type = ANT_A;
1487                         else
1488                                 search_tbl->ant_type = ANT_B;
1489
1490                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1491                                                  search_tbl, index);
1492                         if (!ret) {
1493                                 lq_sta->search_better_tbl = 1;
1494                                 goto out;
1495                         }
1496                         break;
1497
1498                 case IWL_MIMO_SWITCH_GI:
1499                         if (!tbl->is_fat &&
1500                                 !(priv->current_ht_config.sgf &
1501                                                 HT_SHORT_GI_20MHZ))
1502                                 break;
1503                         if (tbl->is_fat &&
1504                                 !(priv->current_ht_config.sgf &
1505                                                 HT_SHORT_GI_40MHZ))
1506                                 break;
1507
1508                         IWL_DEBUG_RATE("LQ: MIMO toggle SGI/NGI\n");
1509
1510                         /* Set up new search table for MIMO */
1511                         memcpy(search_tbl, tbl, sz);
1512                         search_tbl->is_SGI = !tbl->is_SGI;
1513                         rs_set_expected_tpt_table(lq_sta, search_tbl);
1514                         /*
1515                          * If active table already uses the fastest possible
1516                          * modulation (dual stream with short guard interval),
1517                          * and it's working well, there's no need to look
1518                          * for a better type of modulation!
1519                          */
1520                         if (tbl->is_SGI) {
1521                                 s32 tpt = lq_sta->last_tpt / 100;
1522                                 if (tpt >= search_tbl->expected_tpt[index])
1523                                         break;
1524                         }
1525                         search_tbl->current_rate = rate_n_flags_from_tbl(
1526                                                 search_tbl, index, is_green);
1527                         lq_sta->search_better_tbl = 1;
1528                         goto out;
1529
1530                 }
1531                 tbl->action++;
1532                 if (tbl->action > IWL_MIMO_SWITCH_GI)
1533                         tbl->action = IWL_MIMO_SWITCH_ANTENNA_A;
1534
1535                 if (tbl->action == start_action)
1536                         break;
1537         }
1538
1539         return 0;
1540  out:
1541         tbl->action++;
1542         if (tbl->action > IWL_MIMO_SWITCH_GI)
1543                 tbl->action = IWL_MIMO_SWITCH_ANTENNA_A;
1544         return 0;
1545
1546 }
1547
1548 /*
1549  * Check whether we should continue using same modulation mode, or
1550  * begin search for a new mode, based on:
1551  * 1) # tx successes or failures while using this mode
1552  * 2) # times calling this function
1553  * 3) elapsed time in this mode (not used, for now)
1554  */
1555 static void rs_stay_in_table(struct iwl4965_lq_sta *lq_sta)
1556 {
1557         struct iwl4965_scale_tbl_info *tbl;
1558         int i;
1559         int active_tbl;
1560         int flush_interval_passed = 0;
1561         struct iwl_priv *priv;
1562
1563         priv = lq_sta->drv;
1564         active_tbl = lq_sta->active_tbl;
1565
1566         tbl = &(lq_sta->lq_info[active_tbl]);
1567
1568         /* If we've been disallowing search, see if we should now allow it */
1569         if (lq_sta->stay_in_tbl) {
1570
1571                 /* Elapsed time using current modulation mode */
1572                 if (lq_sta->flush_timer)
1573                         flush_interval_passed =
1574                             time_after(jiffies,
1575                                        (unsigned long)(lq_sta->flush_timer +
1576                                         IWL_RATE_SCALE_FLUSH_INTVL));
1577
1578                 /*
1579                  * Check if we should allow search for new modulation mode.
1580                  * If many frames have failed or succeeded, or we've used
1581                  * this same modulation for a long time, allow search, and
1582                  * reset history stats that keep track of whether we should
1583                  * allow a new search.  Also (below) reset all bitmaps and
1584                  * stats in active history.
1585                  */
1586                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1587                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1588                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1589                      && (flush_interval_passed))) {
1590                         IWL_DEBUG_RATE("LQ: stay is expired %d %d %d\n:",
1591                                      lq_sta->total_failed,
1592                                      lq_sta->total_success,
1593                                      flush_interval_passed);
1594
1595                         /* Allow search for new mode */
1596                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1597                         lq_sta->total_failed = 0;
1598                         lq_sta->total_success = 0;
1599                         lq_sta->flush_timer = 0;
1600
1601                 /*
1602                  * Else if we've used this modulation mode enough repetitions
1603                  * (regardless of elapsed time or success/failure), reset
1604                  * history bitmaps and rate-specific stats for all rates in
1605                  * active table.
1606                  */
1607                 } else {
1608                         lq_sta->table_count++;
1609                         if (lq_sta->table_count >=
1610                             lq_sta->table_count_limit) {
1611                                 lq_sta->table_count = 0;
1612
1613                                 IWL_DEBUG_RATE("LQ: stay in table clear win\n");
1614                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1615                                         rs_rate_scale_clear_window(
1616                                                 &(tbl->win[i]));
1617                         }
1618                 }
1619
1620                 /* If transitioning to allow "search", reset all history
1621                  * bitmaps and stats in active table (this will become the new
1622                  * "search" table). */
1623                 if (!lq_sta->stay_in_tbl) {
1624                         for (i = 0; i < IWL_RATE_COUNT; i++)
1625                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1626                 }
1627         }
1628 }
1629
1630 /*
1631  * Do rate scaling and search for new modulation mode.
1632  */
1633 static void rs_rate_scale_perform(struct iwl_priv *priv,
1634                                   struct net_device *dev,
1635                                   struct ieee80211_hdr *hdr,
1636                                   struct sta_info *sta)
1637 {
1638         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1639         struct ieee80211_hw *hw = local_to_hw(local);
1640         struct ieee80211_conf *conf = &hw->conf;
1641         int low = IWL_RATE_INVALID;
1642         int high = IWL_RATE_INVALID;
1643         int index;
1644         int i;
1645         struct iwl4965_rate_scale_data *window = NULL;
1646         int current_tpt = IWL_INVALID_VALUE;
1647         int low_tpt = IWL_INVALID_VALUE;
1648         int high_tpt = IWL_INVALID_VALUE;
1649         u32 fail_count;
1650         s8 scale_action = 0;
1651         __le16 fc;
1652         u16 rate_mask;
1653         u8 update_lq = 0;
1654         struct iwl4965_lq_sta *lq_sta;
1655         struct iwl4965_scale_tbl_info *tbl, *tbl1;
1656         u16 rate_scale_index_msk = 0;
1657         u32 rate;
1658         u8 is_green = 0;
1659         u8 active_tbl = 0;
1660         u8 done_search = 0;
1661         u16 high_low;
1662         s32 sr;
1663         u8 tid = MAX_TID_COUNT;
1664
1665         IWL_DEBUG_RATE("rate scale calculate new rate for skb\n");
1666
1667         fc = hdr->frame_control;
1668         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1)) {
1669                 /* Send management frames and broadcast/multicast data using
1670                  * lowest rate. */
1671                 /* TODO: this could probably be improved.. */
1672                 return;
1673         }
1674
1675         if (!sta || !sta->rate_ctrl_priv)
1676                 return;
1677
1678         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
1679
1680         tid = rs_tl_add_packet(lq_sta, hdr);
1681
1682         /*
1683          * Select rate-scale / modulation-mode table to work with in
1684          * the rest of this function:  "search" if searching for better
1685          * modulation mode, or "active" if doing rate scaling within a mode.
1686          */
1687         if (!lq_sta->search_better_tbl)
1688                 active_tbl = lq_sta->active_tbl;
1689         else
1690                 active_tbl = 1 - lq_sta->active_tbl;
1691
1692         tbl = &(lq_sta->lq_info[active_tbl]);
1693         is_green = lq_sta->is_green;
1694
1695         /* current tx rate */
1696         index = sta->last_txrate_idx;
1697
1698         IWL_DEBUG_RATE("Rate scale index %d for type %d\n", index,
1699                        tbl->lq_type);
1700
1701         /* rates available for this association, and for modulation mode */
1702         rate_mask = rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1703
1704         IWL_DEBUG_RATE("mask 0x%04X \n", rate_mask);
1705
1706         /* mask with station rate restriction */
1707         if (is_legacy(tbl->lq_type)) {
1708                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
1709                         /* supp_rates has no CCK bits in A mode */
1710                         rate_scale_index_msk = (u16) (rate_mask &
1711                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1712                 else
1713                         rate_scale_index_msk = (u16) (rate_mask &
1714                                                       lq_sta->supp_rates);
1715
1716         } else
1717                 rate_scale_index_msk = rate_mask;
1718
1719         if (!rate_scale_index_msk)
1720                 rate_scale_index_msk = rate_mask;
1721
1722         if (!((1 << index) & rate_scale_index_msk)) {
1723                 IWL_ERROR("Current Rate is not valid\n");
1724                 return;
1725         }
1726
1727         /* Get expected throughput table and history window for current rate */
1728         if (!tbl->expected_tpt) {
1729                 IWL_ERROR("tbl->expected_tpt is NULL\n");
1730                 return;
1731         }
1732
1733         window = &(tbl->win[index]);
1734
1735         /*
1736          * If there is not enough history to calculate actual average
1737          * throughput, keep analyzing results of more tx frames, without
1738          * changing rate or mode (bypass most of the rest of this function).
1739          * Set up new rate table in uCode only if old rate is not supported
1740          * in current association (use new rate found above).
1741          */
1742         fail_count = window->counter - window->success_counter;
1743         if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1744                         (window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
1745                 IWL_DEBUG_RATE("LQ: still below TH. succ=%d total=%d "
1746                                "for index %d\n",
1747                                window->success_counter, window->counter, index);
1748
1749                 /* Can't calculate this yet; not enough history */
1750                 window->average_tpt = IWL_INVALID_VALUE;
1751
1752                 /* Should we stay with this modulation mode,
1753                  * or search for a new one? */
1754                 rs_stay_in_table(lq_sta);
1755
1756                 goto out;
1757
1758         /* Else we have enough samples; calculate estimate of
1759          * actual average throughput */
1760         } else {
1761                 /*FIXME:RS remove this else if we don't get this error*/
1762                 if (window->average_tpt != ((window->success_ratio *
1763                                 tbl->expected_tpt[index] + 64) / 128)) {
1764                         IWL_ERROR("expected_tpt should have been calculated"
1765                                                                 " by now\n");
1766                         window->average_tpt = ((window->success_ratio *
1767                                         tbl->expected_tpt[index] + 64) / 128);
1768                 }
1769         }
1770
1771         /* If we are searching for better modulation mode, check success. */
1772         if (lq_sta->search_better_tbl) {
1773
1774                 /* If good success, continue using the "search" mode;
1775                  * no need to send new link quality command, since we're
1776                  * continuing to use the setup that we've been trying. */
1777                 if (window->average_tpt > lq_sta->last_tpt) {
1778
1779                         IWL_DEBUG_RATE("LQ: SWITCHING TO CURRENT TABLE "
1780                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1781                                         window->success_ratio,
1782                                         window->average_tpt,
1783                                         lq_sta->last_tpt);
1784
1785                         if (!is_legacy(tbl->lq_type))
1786                                 lq_sta->enable_counter = 1;
1787
1788                         /* Swap tables; "search" becomes "active" */
1789                         lq_sta->active_tbl = active_tbl;
1790                         current_tpt = window->average_tpt;
1791
1792                 /* Else poor success; go back to mode in "active" table */
1793                 } else {
1794
1795                         IWL_DEBUG_RATE("LQ: GOING BACK TO THE OLD TABLE "
1796                                         "suc=%d cur-tpt=%d old-tpt=%d\n",
1797                                         window->success_ratio,
1798                                         window->average_tpt,
1799                                         lq_sta->last_tpt);
1800
1801                         /* Nullify "search" table */
1802                         tbl->lq_type = LQ_NONE;
1803
1804                         /* Revert to "active" table */
1805                         active_tbl = lq_sta->active_tbl;
1806                         tbl = &(lq_sta->lq_info[active_tbl]);
1807
1808                         /* Revert to "active" rate and throughput info */
1809                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1810                         current_tpt = lq_sta->last_tpt;
1811
1812                         /* Need to set up a new rate table in uCode */
1813                         update_lq = 1;
1814                 }
1815
1816                 /* Either way, we've made a decision; modulation mode
1817                  * search is done, allow rate adjustment next time. */
1818                 lq_sta->search_better_tbl = 0;
1819                 done_search = 1;        /* Don't switch modes below! */
1820                 goto lq_update;
1821         }
1822
1823         /* (Else) not in search of better modulation mode, try for better
1824          * starting rate, while staying in this mode. */
1825         high_low = rs_get_adjacent_rate(priv, index, rate_scale_index_msk,
1826                                         tbl->lq_type);
1827         low = high_low & 0xff;
1828         high = (high_low >> 8) & 0xff;
1829
1830         sr = window->success_ratio;
1831
1832         /* Collect measured throughputs for current and adjacent rates */
1833         current_tpt = window->average_tpt;
1834         if (low != IWL_RATE_INVALID)
1835                 low_tpt = tbl->win[low].average_tpt;
1836         if (high != IWL_RATE_INVALID)
1837                 high_tpt = tbl->win[high].average_tpt;
1838
1839         scale_action = 0;
1840
1841         /* Too many failures, decrease rate */
1842         if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
1843                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
1844                 scale_action = -1;
1845
1846         /* No throughput measured yet for adjacent rates; try increase. */
1847         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1848                    (high_tpt == IWL_INVALID_VALUE)) {
1849
1850                 if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
1851                         scale_action = 1;
1852                 else if (low != IWL_RATE_INVALID)
1853                         scale_action = -1;
1854         }
1855
1856         /* Both adjacent throughputs are measured, but neither one has better
1857          * throughput; we're using the best rate, don't change it! */
1858         else if ((low_tpt != IWL_INVALID_VALUE) &&
1859                  (high_tpt != IWL_INVALID_VALUE) &&
1860                  (low_tpt < current_tpt) &&
1861                  (high_tpt < current_tpt))
1862                 scale_action = 0;
1863
1864         /* At least one adjacent rate's throughput is measured,
1865          * and may have better performance. */
1866         else {
1867                 /* Higher adjacent rate's throughput is measured */
1868                 if (high_tpt != IWL_INVALID_VALUE) {
1869                         /* Higher rate has better throughput */
1870                         if (high_tpt > current_tpt &&
1871                                         sr >= IWL_RATE_INCREASE_TH) {
1872                                 scale_action = 1;
1873                         } else {
1874                                 IWL_DEBUG_RATE
1875                                     ("decrease rate because of high tpt\n");
1876                                 scale_action = -1;
1877                         }
1878
1879                 /* Lower adjacent rate's throughput is measured */
1880                 } else if (low_tpt != IWL_INVALID_VALUE) {
1881                         /* Lower rate has better throughput */
1882                         if (low_tpt > current_tpt) {
1883                                 IWL_DEBUG_RATE
1884                                     ("decrease rate because of low tpt\n");
1885                                 scale_action = -1;
1886                         } else if (sr >= IWL_RATE_INCREASE_TH) {
1887                                 scale_action = 1;
1888                         }
1889                 }
1890         }
1891
1892         /* Sanity check; asked for decrease, but success rate or throughput
1893          * has been good at old rate.  Don't change it. */
1894         if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
1895                     ((sr > IWL_RATE_HIGH_TH) ||
1896                      (current_tpt > (100 * tbl->expected_tpt[low]))))
1897                 scale_action = 0;
1898
1899         switch (scale_action) {
1900         case -1:
1901                 /* Decrease starting rate, update uCode's rate table */
1902                 if (low != IWL_RATE_INVALID) {
1903                         update_lq = 1;
1904                         index = low;
1905                 }
1906                 break;
1907         case 1:
1908                 /* Increase starting rate, update uCode's rate table */
1909                 if (high != IWL_RATE_INVALID) {
1910                         update_lq = 1;
1911                         index = high;
1912                 }
1913
1914                 break;
1915         case 0:
1916                 /* No change */
1917         default:
1918                 break;
1919         }
1920
1921         IWL_DEBUG_RATE("choose rate scale index %d action %d low %d "
1922                     "high %d type %d\n",
1923                      index, scale_action, low, high, tbl->lq_type);
1924
1925 lq_update:
1926         /* Replace uCode's rate table for the destination station. */
1927         if (update_lq) {
1928                 rate = rate_n_flags_from_tbl(tbl, index, is_green);
1929                 rs_fill_link_cmd(priv, lq_sta, rate);
1930                 iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1931         }
1932
1933         /* Should we stay with this modulation mode, or search for a new one? */
1934         rs_stay_in_table(lq_sta);
1935
1936         /*
1937          * Search for new modulation mode if we're:
1938          * 1)  Not changing rates right now
1939          * 2)  Not just finishing up a search
1940          * 3)  Allowing a new search
1941          */
1942         if (!update_lq && !done_search && !lq_sta->stay_in_tbl && window->counter) {
1943                 /* Save current throughput to compare with "search" throughput*/
1944                 lq_sta->last_tpt = current_tpt;
1945
1946                 /* Select a new "search" modulation mode to try.
1947                  * If one is found, set up the new "search" table. */
1948                 if (is_legacy(tbl->lq_type))
1949                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
1950                 else if (is_siso(tbl->lq_type))
1951                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
1952                 else
1953                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
1954
1955                 /* If new "search" mode was selected, set up in uCode table */
1956                 if (lq_sta->search_better_tbl) {
1957                         /* Access the "search" table, clear its history. */
1958                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1959                         for (i = 0; i < IWL_RATE_COUNT; i++)
1960                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1961
1962                         /* Use new "search" start rate */
1963                         index = iwl_hwrate_to_plcp_idx(tbl->current_rate);
1964
1965                         IWL_DEBUG_RATE("Switch current  mcs: %X index: %d\n",
1966                                      tbl->current_rate, index);
1967                         rs_fill_link_cmd(priv, lq_sta, tbl->current_rate);
1968                         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1969                 }
1970
1971                 /* If the "active" (non-search) mode was legacy,
1972                  * and we've tried switching antennas,
1973                  * but we haven't been able to try HT modes (not available),
1974                  * stay with best antenna legacy modulation for a while
1975                  * before next round of mode comparisons. */
1976                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
1977                 if (is_legacy(tbl1->lq_type) &&
1978                    (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE)) &&
1979                     (lq_sta->action_counter >= 1)) {
1980                         lq_sta->action_counter = 0;
1981                         IWL_DEBUG_RATE("LQ: STAY in legacy table\n");
1982                         rs_set_stay_in_table(priv, 1, lq_sta);
1983                 }
1984
1985                 /* If we're in an HT mode, and all 3 mode switch actions
1986                  * have been tried and compared, stay in this best modulation
1987                  * mode for a while before next round of mode comparisons. */
1988                 if (lq_sta->enable_counter &&
1989                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
1990                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
1991                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
1992                             (tid != MAX_TID_COUNT)) {
1993                                 IWL_DEBUG_RATE("try to aggregate tid %d\n", tid);
1994                                 rs_tl_turn_on_agg(priv, tid, lq_sta, sta);
1995                         }
1996                         lq_sta->action_counter = 0;
1997                         rs_set_stay_in_table(priv, 0, lq_sta);
1998                 }
1999
2000         /*
2001          * Else, don't search for a new modulation mode.
2002          * Put new timestamp in stay-in-modulation-mode flush timer if:
2003          * 1)  Not changing rates right now
2004          * 2)  Not just finishing up a search
2005          * 3)  flush timer is empty
2006          */
2007         } else {
2008                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
2009                         lq_sta->flush_timer = jiffies;
2010         }
2011
2012 out:
2013         tbl->current_rate = rate_n_flags_from_tbl(tbl, index, is_green);
2014         i = index;
2015         sta->last_txrate_idx = i;
2016
2017         /* sta->txrate_idx is an index to A mode rates which start
2018          * at IWL_FIRST_OFDM_RATE
2019          */
2020         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2021                 sta->txrate_idx = i - IWL_FIRST_OFDM_RATE;
2022         else
2023                 sta->txrate_idx = i;
2024
2025         return;
2026 }
2027
2028
2029 static void rs_initialize_lq(struct iwl_priv *priv,
2030                              struct ieee80211_conf *conf,
2031                              struct sta_info *sta)
2032 {
2033         struct iwl4965_lq_sta *lq_sta;
2034         struct iwl4965_scale_tbl_info *tbl;
2035         int rate_idx;
2036         int i;
2037         u32 rate;
2038         u8 use_green = rs_use_green(priv, conf);
2039         u8 active_tbl = 0;
2040         u8 valid_tx_ant;
2041
2042         if (!sta || !sta->rate_ctrl_priv)
2043                 goto out;
2044
2045         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
2046         i = sta->last_txrate_idx;
2047
2048         if ((lq_sta->lq.sta_id == 0xff) &&
2049             (priv->iw_mode == IEEE80211_IF_TYPE_IBSS))
2050                 goto out;
2051
2052         valid_tx_ant = priv->hw_params.valid_tx_ant;
2053
2054         if (!lq_sta->search_better_tbl)
2055                 active_tbl = lq_sta->active_tbl;
2056         else
2057                 active_tbl = 1 - lq_sta->active_tbl;
2058
2059         tbl = &(lq_sta->lq_info[active_tbl]);
2060
2061         if ((i < 0) || (i >= IWL_RATE_COUNT))
2062                 i = 0;
2063
2064         /* FIXME:RS: This is also wrong in 4965 */
2065         rate = iwl_rates[i].plcp;
2066         rate |= RATE_MCS_ANT_B_MSK;
2067         rate &= ~RATE_MCS_ANT_A_MSK;
2068
2069         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2070                 rate |= RATE_MCS_CCK_MSK;
2071
2072         tbl->ant_type = ANT_B;
2073         rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2074         if (!rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2075             rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2076
2077         rate = rate_n_flags_from_tbl(tbl, rate_idx, use_green);
2078         tbl->current_rate = rate;
2079         rs_set_expected_tpt_table(lq_sta, tbl);
2080         rs_fill_link_cmd(NULL, lq_sta, rate);
2081         iwl_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2082  out:
2083         return;
2084 }
2085
2086 static void rs_get_rate(void *priv_rate, struct net_device *dev,
2087                         struct ieee80211_supported_band *sband,
2088                         struct sk_buff *skb,
2089                         struct rate_selection *sel)
2090 {
2091
2092         int i;
2093         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
2094         struct ieee80211_conf *conf = &local->hw.conf;
2095         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2096         struct sta_info *sta;
2097         __le16 fc;
2098         struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
2099         struct iwl4965_lq_sta *lq_sta;
2100
2101         IWL_DEBUG_RATE_LIMIT("rate scale calculate new rate for skb\n");
2102
2103         rcu_read_lock();
2104
2105         sta = sta_info_get(local, hdr->addr1);
2106
2107         /* Send management frames and broadcast/multicast data using lowest
2108          * rate. */
2109         fc = hdr->frame_control;
2110         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1) ||
2111             !sta || !sta->rate_ctrl_priv) {
2112                 sel->rate_idx = rate_lowest_index(local, sband, sta);
2113                 goto out;
2114         }
2115
2116         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
2117         i = sta->last_txrate_idx;
2118
2119         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
2120             !lq_sta->ibss_sta_added) {
2121                 u8 sta_id = iwl_find_station(priv, hdr->addr1);
2122                 DECLARE_MAC_BUF(mac);
2123
2124                 if (sta_id == IWL_INVALID_STATION) {
2125                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
2126                                        print_mac(mac, hdr->addr1));
2127                         sta_id = iwl_add_station_flags(priv, hdr->addr1,
2128                                                         0, CMD_ASYNC, NULL);
2129                 }
2130                 if ((sta_id != IWL_INVALID_STATION)) {
2131                         lq_sta->lq.sta_id = sta_id;
2132                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2133                         lq_sta->ibss_sta_added = 1;
2134                         rs_initialize_lq(priv, conf, sta);
2135                 }
2136         }
2137
2138         if ((i < 0) || (i > IWL_RATE_COUNT)) {
2139                 sel->rate_idx = rate_lowest_index(local, sband, sta);
2140                 goto out;
2141         }
2142
2143         if (sband->band == IEEE80211_BAND_5GHZ)
2144                 i -= IWL_FIRST_OFDM_RATE;
2145         sel->rate_idx = i;
2146 out:
2147         rcu_read_unlock();
2148 }
2149
2150 static void *rs_alloc_sta(void *priv_rate, gfp_t gfp)
2151 {
2152         struct iwl4965_lq_sta *lq_sta;
2153         struct iwl_priv *priv;
2154         int i, j;
2155
2156         priv = (struct iwl_priv *)priv_rate;
2157         IWL_DEBUG_RATE("create station rate scale window\n");
2158
2159         lq_sta = kzalloc(sizeof(struct iwl4965_lq_sta), gfp);
2160
2161         if (lq_sta == NULL)
2162                 return NULL;
2163         lq_sta->lq.sta_id = 0xff;
2164
2165
2166         for (j = 0; j < LQ_SIZE; j++)
2167                 for (i = 0; i < IWL_RATE_COUNT; i++)
2168                         rs_rate_scale_clear_window(&(lq_sta->lq_info[j].win[i]));
2169
2170         return lq_sta;
2171 }
2172
2173 static void rs_rate_init(void *priv_rate, void *priv_sta,
2174                          struct ieee80211_local *local,
2175                          struct sta_info *sta)
2176 {
2177         int i, j;
2178         struct ieee80211_conf *conf = &local->hw.conf;
2179         struct ieee80211_supported_band *sband;
2180         struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
2181         struct iwl4965_lq_sta *lq_sta = priv_sta;
2182
2183         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
2184
2185         lq_sta->flush_timer = 0;
2186         lq_sta->supp_rates = sta->supp_rates[sband->band];
2187         sta->txrate_idx = 3;
2188         for (j = 0; j < LQ_SIZE; j++)
2189                 for (i = 0; i < IWL_RATE_COUNT; i++)
2190                         rs_rate_scale_clear_window(&(lq_sta->lq_info[j].win[i]));
2191
2192         IWL_DEBUG_RATE("LQ: *** rate scale global init ***\n");
2193         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2194          * the lowest or the highest rate.. Could consider using RSSI from
2195          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2196          * after assoc.. */
2197
2198         lq_sta->ibss_sta_added = 0;
2199         if (priv->iw_mode == IEEE80211_IF_TYPE_AP) {
2200                 u8 sta_id = iwl_find_station(priv, sta->addr);
2201                 DECLARE_MAC_BUF(mac);
2202
2203                 /* for IBSS the call are from tasklet */
2204                 IWL_DEBUG_RATE("LQ: ADD station %s\n",
2205                              print_mac(mac, sta->addr));
2206
2207                 if (sta_id == IWL_INVALID_STATION) {
2208                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
2209                                        print_mac(mac, sta->addr));
2210                         sta_id = iwl_add_station_flags(priv, sta->addr,
2211                                                         0, CMD_ASYNC, NULL);
2212                 }
2213                 if ((sta_id != IWL_INVALID_STATION)) {
2214                         lq_sta->lq.sta_id = sta_id;
2215                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2216                 }
2217                 /* FIXME: this is w/a remove it later */
2218                 priv->assoc_station_added = 1;
2219         }
2220
2221         /* Find highest tx rate supported by hardware and destination station */
2222         for (i = 0; i < sband->n_bitrates; i++)
2223                 if (sta->supp_rates[sband->band] & BIT(i))
2224                         sta->txrate_idx = i;
2225
2226         sta->last_txrate_idx = sta->txrate_idx;
2227         /* WTF is with this bogus comment? A doesn't have cck rates */
2228         /* For MODE_IEEE80211A, cck rates are at end of rate table */
2229         if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ)
2230                 sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2231
2232         lq_sta->is_dup = 0;
2233         lq_sta->is_green = rs_use_green(priv, conf);
2234         lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2235         lq_sta->active_rate_basic = priv->active_rate_basic;
2236         lq_sta->band = priv->band;
2237         /*
2238          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2239          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2240          */
2241         lq_sta->active_siso_rate = conf->ht_conf.supp_mcs_set[0] << 1;
2242         lq_sta->active_siso_rate |= conf->ht_conf.supp_mcs_set[0] & 0x1;
2243         lq_sta->active_siso_rate &= ~((u16)0x2);
2244         lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2245
2246         /* Same here */
2247         lq_sta->active_mimo2_rate = conf->ht_conf.supp_mcs_set[1] << 1;
2248         lq_sta->active_mimo2_rate |= conf->ht_conf.supp_mcs_set[1] & 0x1;
2249         lq_sta->active_mimo2_rate &= ~((u16)0x2);
2250         lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2251
2252         lq_sta->active_mimo3_rate = conf->ht_conf.supp_mcs_set[2] << 1;
2253         lq_sta->active_mimo3_rate |= conf->ht_conf.supp_mcs_set[2] & 0x1;
2254         lq_sta->active_mimo3_rate &= ~((u16)0x2);
2255         lq_sta->active_mimo3_rate <<= IWL_FIRST_OFDM_RATE;
2256
2257         IWL_DEBUG_RATE("SISO-RATE=%X MIMO2-RATE=%X MIMO3-RATE=%X\n",
2258                      lq_sta->active_siso_rate,
2259                      lq_sta->active_mimo2_rate,
2260                      lq_sta->active_mimo3_rate);
2261
2262         /* These values will be overriden later */
2263         lq_sta->lq.general_params.single_stream_ant_msk = ANT_A;
2264         lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2265
2266         /* as default allow aggregation for all tids */
2267         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2268         lq_sta->drv = priv;
2269
2270         rs_initialize_lq(priv, conf, sta);
2271 }
2272
2273 static void rs_fill_link_cmd(const struct iwl_priv *priv,
2274                              struct iwl4965_lq_sta *lq_sta,
2275                              u32 new_rate)
2276 {
2277         struct iwl4965_scale_tbl_info tbl_type;
2278         int index = 0;
2279         int rate_idx;
2280         int repeat_rate = 0;
2281         u8 ant_toggle_cnt = 0;
2282         u8 use_ht_possible = 1;
2283         u8 valid_tx_ant = 0;
2284         struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2285
2286         /* Override starting rate (index 0) if needed for debug purposes */
2287         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2288
2289         /* Interpret new_rate (rate_n_flags) */
2290         memset(&tbl_type, 0, sizeof(tbl_type));
2291         rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2292                                   &tbl_type, &rate_idx);
2293
2294         /* How many times should we repeat the initial rate? */
2295         if (is_legacy(tbl_type.lq_type)) {
2296                 ant_toggle_cnt = 1;
2297                 repeat_rate = IWL_NUMBER_TRY;
2298         } else {
2299                 repeat_rate = IWL_HT_NUMBER_TRY;
2300         }
2301
2302         lq_cmd->general_params.mimo_delimiter =
2303                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2304
2305         /* Fill 1st table entry (index 0) */
2306         lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2307
2308         if (num_of_ant(tbl_type.ant_type) == 1) {
2309                 lq_cmd->general_params.single_stream_ant_msk =
2310                                                 tbl_type.ant_type;
2311         } else if (num_of_ant(tbl_type.ant_type) == 2) {
2312                 lq_cmd->general_params.dual_stream_ant_msk =
2313                                                 tbl_type.ant_type;
2314         } /* otherwise we don't modify the existing value */
2315
2316         index++;
2317         repeat_rate--;
2318
2319         if (priv)
2320                 valid_tx_ant = priv->hw_params.valid_tx_ant;
2321
2322         /* Fill rest of rate table */
2323         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2324                 /* Repeat initial/next rate.
2325                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2326                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2327                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2328                         if (is_legacy(tbl_type.lq_type)) {
2329                                 if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2330                                         ant_toggle_cnt++;
2331                                 else if (priv &&
2332                                          rs_toggle_antenna(valid_tx_ant,
2333                                                         &new_rate, &tbl_type))
2334                                         ant_toggle_cnt = 1;
2335 }
2336
2337                         /* Override next rate if needed for debug purposes */
2338                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2339
2340                         /* Fill next table entry */
2341                         lq_cmd->rs_table[index].rate_n_flags =
2342                                         cpu_to_le32(new_rate);
2343                         repeat_rate--;
2344                         index++;
2345                 }
2346
2347                 rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2348                                                 &rate_idx);
2349
2350                 /* Indicate to uCode which entries might be MIMO.
2351                  * If initial rate was MIMO, this will finally end up
2352                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2353                 if (is_mimo(tbl_type.lq_type))
2354                         lq_cmd->general_params.mimo_delimiter = index;
2355
2356                 /* Get next rate */
2357                 new_rate = rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2358                                              use_ht_possible);
2359
2360                 /* How many times should we repeat the next rate? */
2361                 if (is_legacy(tbl_type.lq_type)) {
2362                         if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2363                                 ant_toggle_cnt++;
2364                         else if (priv &&
2365                                  rs_toggle_antenna(valid_tx_ant,
2366                                                    &new_rate, &tbl_type))
2367                                 ant_toggle_cnt = 1;
2368
2369                         repeat_rate = IWL_NUMBER_TRY;
2370                 } else {
2371                         repeat_rate = IWL_HT_NUMBER_TRY;
2372                 }
2373
2374                 /* Don't allow HT rates after next pass.
2375                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2376                 use_ht_possible = 0;
2377
2378                 /* Override next rate if needed for debug purposes */
2379                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2380
2381                 /* Fill next table entry */
2382                 lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2383
2384                 index++;
2385                 repeat_rate--;
2386         }
2387
2388         lq_cmd->agg_params.agg_frame_cnt_limit = 64;
2389         lq_cmd->agg_params.agg_dis_start_th = 3;
2390         lq_cmd->agg_params.agg_time_limit = cpu_to_le16(4000);
2391 }
2392
2393 static void *rs_alloc(struct ieee80211_local *local)
2394 {
2395         return local->hw.priv;
2396 }
2397 /* rate scale requires free function to be implemented */
2398 static void rs_free(void *priv_rate)
2399 {
2400         return;
2401 }
2402
2403 static void rs_clear(void *priv_rate)
2404 {
2405         struct iwl_priv *priv = (struct iwl_priv *) priv_rate;
2406
2407         IWL_DEBUG_RATE("enter\n");
2408
2409         /* TODO - add rate scale state reset */
2410
2411         IWL_DEBUG_RATE("leave\n");
2412 }
2413
2414 static void rs_free_sta(void *priv_rate, void *priv_sta)
2415 {
2416         struct iwl4965_lq_sta *lq_sta = priv_sta;
2417         struct iwl_priv *priv;
2418
2419         priv = (struct iwl_priv *)priv_rate;
2420         IWL_DEBUG_RATE("enter\n");
2421         kfree(lq_sta);
2422         IWL_DEBUG_RATE("leave\n");
2423 }
2424
2425
2426 #ifdef CONFIG_MAC80211_DEBUGFS
2427 static int open_file_generic(struct inode *inode, struct file *file)
2428 {
2429         file->private_data = inode->i_private;
2430         return 0;
2431 }
2432 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
2433                                 u32 *rate_n_flags, int index)
2434 {
2435         struct iwl_priv *priv;
2436
2437         priv = lq_sta->drv;
2438         if (lq_sta->dbg_fixed_rate) {
2439                 if (index < 12) {
2440                         *rate_n_flags = lq_sta->dbg_fixed_rate;
2441                 } else {
2442                         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2443                                 *rate_n_flags = 0x800D;
2444                         else
2445                                 *rate_n_flags = 0x820A;
2446                 }
2447                 IWL_DEBUG_RATE("Fixed rate ON\n");
2448         } else {
2449                 IWL_DEBUG_RATE("Fixed rate OFF\n");
2450         }
2451 }
2452
2453 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2454                         const char __user *user_buf, size_t count, loff_t *ppos)
2455 {
2456         struct iwl4965_lq_sta *lq_sta = file->private_data;
2457         struct iwl_priv *priv;
2458         char buf[64];
2459         int buf_size;
2460         u32 parsed_rate;
2461
2462         priv = lq_sta->drv;
2463         memset(buf, 0, sizeof(buf));
2464         buf_size = min(count, sizeof(buf) -  1);
2465         if (copy_from_user(buf, user_buf, buf_size))
2466                 return -EFAULT;
2467
2468         if (sscanf(buf, "%x", &parsed_rate) == 1)
2469                 lq_sta->dbg_fixed_rate = parsed_rate;
2470         else
2471                 lq_sta->dbg_fixed_rate = 0;
2472
2473         lq_sta->active_legacy_rate = 0x0FFF;    /* 1 - 54 MBits, includes CCK */
2474         lq_sta->active_siso_rate   = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2475         lq_sta->active_mimo2_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2476         lq_sta->active_mimo3_rate  = 0x1FD0;    /* 6 - 60 MBits, no 9, no CCK */
2477
2478         IWL_DEBUG_RATE("sta_id %d rate 0x%X\n",
2479                 lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2480
2481         if (lq_sta->dbg_fixed_rate) {
2482                 rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2483                 iwl_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2484         }
2485
2486         return count;
2487 }
2488
2489 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2490                         char __user *user_buf, size_t count, loff_t *ppos)
2491 {
2492         char buff[1024];
2493         int desc = 0;
2494         int i = 0;
2495
2496         struct iwl4965_lq_sta *lq_sta = file->private_data;
2497
2498         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2499         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2500                         lq_sta->total_failed, lq_sta->total_success,
2501                         lq_sta->active_legacy_rate);
2502         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2503                         lq_sta->dbg_fixed_rate);
2504         desc += sprintf(buff+desc, "general:"
2505                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2506                 lq_sta->lq.general_params.flags,
2507                 lq_sta->lq.general_params.mimo_delimiter,
2508                 lq_sta->lq.general_params.single_stream_ant_msk,
2509                 lq_sta->lq.general_params.dual_stream_ant_msk);
2510
2511         desc += sprintf(buff+desc, "agg:"
2512                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2513                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2514                         lq_sta->lq.agg_params.agg_dis_start_th,
2515                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2516
2517         desc += sprintf(buff+desc,
2518                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2519                         lq_sta->lq.general_params.start_rate_index[0],
2520                         lq_sta->lq.general_params.start_rate_index[1],
2521                         lq_sta->lq.general_params.start_rate_index[2],
2522                         lq_sta->lq.general_params.start_rate_index[3]);
2523
2524
2525         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2526                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2527                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2528
2529         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2530 }
2531
2532 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2533         .write = rs_sta_dbgfs_scale_table_write,
2534         .read = rs_sta_dbgfs_scale_table_read,
2535         .open = open_file_generic,
2536 };
2537 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2538                         char __user *user_buf, size_t count, loff_t *ppos)
2539 {
2540         char buff[1024];
2541         int desc = 0;
2542         int i, j;
2543
2544         struct iwl4965_lq_sta *lq_sta = file->private_data;
2545         for (i = 0; i < LQ_SIZE; i++) {
2546                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2547                                 "rate=0x%X\n",
2548                                 lq_sta->active_tbl == i?"*":"x",
2549                                 lq_sta->lq_info[i].lq_type,
2550                                 lq_sta->lq_info[i].is_SGI,
2551                                 lq_sta->lq_info[i].is_fat,
2552                                 lq_sta->lq_info[i].is_dup,
2553                                 lq_sta->lq_info[i].current_rate);
2554                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2555                         desc += sprintf(buff+desc,
2556                                 "counter=%d success=%d %%=%d\n",
2557                                 lq_sta->lq_info[i].win[j].counter,
2558                                 lq_sta->lq_info[i].win[j].success_counter,
2559                                 lq_sta->lq_info[i].win[j].success_ratio);
2560                 }
2561         }
2562         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2563 }
2564
2565 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2566         .read = rs_sta_dbgfs_stats_table_read,
2567         .open = open_file_generic,
2568 };
2569
2570 static void rs_add_debugfs(void *priv, void *priv_sta,
2571                                         struct dentry *dir)
2572 {
2573         struct iwl4965_lq_sta *lq_sta = priv_sta;
2574         lq_sta->rs_sta_dbgfs_scale_table_file =
2575                 debugfs_create_file("rate_scale_table", 0600, dir,
2576                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2577         lq_sta->rs_sta_dbgfs_stats_table_file =
2578                 debugfs_create_file("rate_stats_table", 0600, dir,
2579                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2580         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2581                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2582                 &lq_sta->tx_agg_tid_en);
2583
2584 }
2585
2586 static void rs_remove_debugfs(void *priv, void *priv_sta)
2587 {
2588         struct iwl4965_lq_sta *lq_sta = priv_sta;
2589         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2590         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2591         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2592 }
2593 #endif
2594
2595 static struct rate_control_ops rs_ops = {
2596         .module = NULL,
2597         .name = RS_NAME,
2598         .tx_status = rs_tx_status,
2599         .get_rate = rs_get_rate,
2600         .rate_init = rs_rate_init,
2601         .clear = rs_clear,
2602         .alloc = rs_alloc,
2603         .free = rs_free,
2604         .alloc_sta = rs_alloc_sta,
2605         .free_sta = rs_free_sta,
2606 #ifdef CONFIG_MAC80211_DEBUGFS
2607         .add_sta_debugfs = rs_add_debugfs,
2608         .remove_sta_debugfs = rs_remove_debugfs,
2609 #endif
2610 };
2611
2612 int iwl4965_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
2613 {
2614         struct ieee80211_local *local = hw_to_local(hw);
2615         struct iwl_priv *priv = hw->priv;
2616         struct iwl4965_lq_sta *lq_sta;
2617         struct sta_info *sta;
2618         int cnt = 0, i;
2619         u32 samples = 0, success = 0, good = 0;
2620         unsigned long now = jiffies;
2621         u32 max_time = 0;
2622         u8 lq_type, antenna;
2623
2624         rcu_read_lock();
2625
2626         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
2627         if (!sta || !sta->rate_ctrl_priv) {
2628                 if (sta)
2629                         IWL_DEBUG_RATE("leave - no private rate data!\n");
2630                 else
2631                         IWL_DEBUG_RATE("leave - no station!\n");
2632                 rcu_read_unlock();
2633                 return sprintf(buf, "station %d not found\n", sta_id);
2634         }
2635
2636         lq_sta = (void *)sta->rate_ctrl_priv;
2637
2638         lq_type = lq_sta->lq_info[lq_sta->active_tbl].lq_type;
2639         antenna = lq_sta->lq_info[lq_sta->active_tbl].ant_type;
2640
2641         if (is_legacy(lq_type))
2642                 i = IWL_RATE_54M_INDEX;
2643         else
2644                 i = IWL_RATE_60M_INDEX;
2645         while (1) {
2646                 u64 mask;
2647                 int j;
2648                 int active = lq_sta->active_tbl;
2649
2650                 cnt +=
2651                     sprintf(&buf[cnt], " %2dMbs: ", iwl_rates[i].ieee / 2);
2652
2653                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
2654                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
2655                         buf[cnt++] =
2656                                 (lq_sta->lq_info[active].win[i].data & mask)
2657                                 ? '1' : '0';
2658
2659                 samples += lq_sta->lq_info[active].win[i].counter;
2660                 good += lq_sta->lq_info[active].win[i].success_counter;
2661                 success += lq_sta->lq_info[active].win[i].success_counter *
2662                            iwl_rates[i].ieee;
2663
2664                 if (lq_sta->lq_info[active].win[i].stamp) {
2665                         int delta =
2666                                    jiffies_to_msecs(now -
2667                                    lq_sta->lq_info[active].win[i].stamp);
2668
2669                         if (delta > max_time)
2670                                 max_time = delta;
2671
2672                         cnt += sprintf(&buf[cnt], "%5dms\n", delta);
2673                 } else
2674                         buf[cnt++] = '\n';
2675
2676                 j = iwl4965_get_prev_ieee_rate(i);
2677                 if (j == i)
2678                         break;
2679                 i = j;
2680         }
2681
2682         /*
2683          * Display the average rate of all samples taken.
2684          * NOTE: We multiply # of samples by 2 since the IEEE measurement
2685          * added from iwl_rates is actually 2X the rate.
2686          */
2687         if (samples)
2688                 cnt += sprintf(&buf[cnt],
2689                          "\nAverage rate is %3d.%02dMbs over last %4dms\n"
2690                          "%3d%% success (%d good packets over %d tries)\n",
2691                          success / (2 * samples), (success * 5 / samples) % 10,
2692                          max_time, good * 100 / samples, good, samples);
2693         else
2694                 cnt += sprintf(&buf[cnt], "\nAverage rate: 0Mbs\n");
2695
2696         cnt += sprintf(&buf[cnt], "\nrate scale type %d antenna %d "
2697                          "active_search %d rate index %d\n", lq_type, antenna,
2698                          lq_sta->search_better_tbl, sta->last_txrate_idx);
2699
2700         rcu_read_unlock();
2701         return cnt;
2702 }
2703
2704 int iwl4965_rate_control_register(void)
2705 {
2706         return ieee80211_rate_control_register(&rs_ops);
2707 }
2708
2709 void iwl4965_rate_control_unregister(void)
2710 {
2711         ieee80211_rate_control_unregister(&rs_ops);
2712 }
2713