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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 #include <net/ieee80211.h>
32
33 #include <linux/netdevice.h>
34 #include <linux/etherdevice.h>
35 #include <linux/delay.h>
36
37 #include <linux/workqueue.h>
38
39 #include "../net/mac80211/ieee80211_rate.h"
40
41 #include "iwl-4965.h"
42 #include "iwl-helpers.h"
43
44 #define RS_NAME "iwl-4965-rs"
45
46 #define NUM_TRY_BEFORE_ANTENNA_TOGGLE 1
47 #define IWL_NUMBER_TRY      1
48 #define IWL_HT_NUMBER_TRY   3
49
50 #define IWL_RATE_MAX_WINDOW             62      /* # tx in history window */
51 #define IWL_RATE_MIN_FAILURE_TH         6       /* min failures to calc tpt */
52 #define IWL_RATE_MIN_SUCCESS_TH         8       /* min successes to calc tpt */
53
54 /* max time to accum history 2 seconds */
55 #define IWL_RATE_SCALE_FLUSH_INTVL   (2*HZ)
56
57 static u8 rs_ht_to_legacy[] = {
58         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
59         IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
60         IWL_RATE_6M_INDEX,
61         IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
62         IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
63         IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
64         IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
65 };
66
67 struct iwl4965_rate {
68         u32 rate_n_flags;
69 } __attribute__ ((packed));
70
71 /**
72  * struct iwl4965_rate_scale_data -- tx success history for one rate
73  */
74 struct iwl4965_rate_scale_data {
75         u64 data;               /* bitmap of successful frames */
76         s32 success_counter;    /* number of frames successful */
77         s32 success_ratio;      /* per-cent * 128  */
78         s32 counter;            /* number of frames attempted */
79         s32 average_tpt;        /* success ratio * expected throughput */
80         unsigned long stamp;
81 };
82
83 /**
84  * struct iwl4965_scale_tbl_info -- tx params and success history for all rates
85  *
86  * There are two of these in struct iwl4965_lq_sta,
87  * one for "active", and one for "search".
88  */
89 struct iwl4965_scale_tbl_info {
90         enum iwl4965_table_type lq_type;
91         enum iwl4965_antenna_type antenna_type;
92         u8 is_SGI;      /* 1 = short guard interval */
93         u8 is_fat;      /* 1 = 40 MHz channel width */
94         u8 is_dup;      /* 1 = duplicated data streams */
95         u8 action;      /* change modulation; IWL_[LEGACY/SISO/MIMO]_SWITCH_* */
96         s32 *expected_tpt;      /* throughput metrics; expected_tpt_G, etc. */
97         struct iwl4965_rate current_rate;  /* rate_n_flags, uCode API format */
98         struct iwl4965_rate_scale_data win[IWL_RATE_COUNT]; /* rate histories */
99 };
100
101 #ifdef CONFIG_IWL4965_HT
102
103 struct iwl4965_traffic_load {
104         unsigned long time_stamp;       /* age of the oldest statistics */
105         u32 packet_count[TID_QUEUE_MAX_SIZE];   /* packet count in this time
106                                                  * slice */
107         u32 total;                      /* total num of packets during the
108                                          * last TID_MAX_TIME_DIFF */
109         u8 queue_count;                 /* number of queues that has
110                                          * been used since the last cleanup */
111         u8 head;                        /* start of the circular buffer */
112 };
113
114 #endif /* CONFIG_IWL4965_HT */
115
116 /**
117  * struct iwl4965_lq_sta -- driver's rate scaling private structure
118  *
119  * Pointer to this gets passed back and forth between driver and mac80211.
120  */
121 struct iwl4965_lq_sta {
122         u8 active_tbl;          /* index of active table, range 0-1 */
123         u8 enable_counter;      /* indicates HT mode */
124         u8 stay_in_tbl;         /* 1: disallow, 0: allow search for new mode */
125         u8 search_better_tbl;   /* 1: currently trying alternate mode */
126         s32 last_tpt;
127
128         /* The following determine when to search for a new mode */
129         u32 table_count_limit;
130         u32 max_failure_limit;  /* # failed frames before new search */
131         u32 max_success_limit;  /* # successful frames before new search */
132         u32 table_count;
133         u32 total_failed;       /* total failed frames, any/all rates */
134         u32 total_success;      /* total successful frames, any/all rates */
135         u32 flush_timer;        /* time staying in mode before new search */
136
137         u8 action_counter;      /* # mode-switch actions tried */
138         u8 antenna;
139         u8 valid_antenna;
140         u8 is_green;
141         u8 is_dup;
142         enum ieee80211_band band;
143         u8 ibss_sta_added;
144
145         /* The following are bitmaps of rates; IWL_RATE_6M_MASK, etc. */
146         u32 supp_rates;
147         u16 active_rate;
148         u16 active_siso_rate;
149         u16 active_mimo_rate;
150         u16 active_rate_basic;
151
152         struct iwl4965_link_quality_cmd lq;
153         struct iwl4965_scale_tbl_info lq_info[LQ_SIZE]; /* "active", "search" */
154 #ifdef CONFIG_IWL4965_HT
155         struct iwl4965_traffic_load load[TID_MAX_LOAD_COUNT];
156         u8 tx_agg_tid_en;
157 #endif
158 #ifdef CONFIG_MAC80211_DEBUGFS
159         struct dentry *rs_sta_dbgfs_scale_table_file;
160         struct dentry *rs_sta_dbgfs_stats_table_file;
161 #ifdef CONFIG_IWL4965_HT
162         struct dentry *rs_sta_dbgfs_tx_agg_tid_en_file;
163 #endif
164         struct iwl4965_rate dbg_fixed;
165         struct iwl4965_priv *drv;
166 #endif
167 };
168
169 static void rs_rate_scale_perform(struct iwl4965_priv *priv,
170                                    struct net_device *dev,
171                                    struct ieee80211_hdr *hdr,
172                                    struct sta_info *sta);
173 static void rs_fill_link_cmd(struct iwl4965_lq_sta *lq_sta,
174                              struct iwl4965_rate *tx_mcs,
175                              struct iwl4965_link_quality_cmd *tbl);
176
177
178 #ifdef CONFIG_MAC80211_DEBUGFS
179 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
180                                 struct iwl4965_rate *mcs, int index);
181 #else
182 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
183                                 struct iwl4965_rate *mcs, int index)
184 {}
185 #endif
186
187 /*
188  * Expected throughput metrics for following rates:
189  * 1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
190  * "G" is the only table that supports CCK (the first 4 rates).
191  */
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 int iwl4965_lq_sync_callback(struct iwl4965_priv *priv,
233                                 struct iwl4965_cmd *cmd, struct sk_buff *skb)
234 {
235         /*We didn't cache the SKB; let the caller free it */
236         return 1;
237 }
238
239 static inline u8 iwl4965_rate_get_rate(u32 rate_n_flags)
240 {
241         return (u8)(rate_n_flags & 0xFF);
242 }
243
244 static int rs_send_lq_cmd(struct iwl4965_priv *priv,
245                           struct iwl4965_link_quality_cmd *lq, u8 flags)
246 {
247 #ifdef CONFIG_IWL4965_DEBUG
248         int i;
249 #endif
250         struct iwl4965_host_cmd cmd = {
251                 .id = REPLY_TX_LINK_QUALITY_CMD,
252                 .len = sizeof(struct iwl4965_link_quality_cmd),
253                 .meta.flags = flags,
254                 .data = lq,
255         };
256
257         if ((lq->sta_id == 0xFF) &&
258             (priv->iw_mode == IEEE80211_IF_TYPE_IBSS))
259                 return -EINVAL;
260
261         if (lq->sta_id == 0xFF)
262                 lq->sta_id = IWL_AP_ID;
263
264         IWL_DEBUG_RATE("lq station id 0x%x\n", lq->sta_id);
265         IWL_DEBUG_RATE("lq dta 0x%X 0x%X\n",
266                        lq->general_params.single_stream_ant_msk,
267                        lq->general_params.dual_stream_ant_msk);
268 #ifdef CONFIG_IWL4965_DEBUG
269         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
270                 IWL_DEBUG_RATE("lq index %d 0x%X\n",
271                                 i, lq->rs_table[i].rate_n_flags);
272 #endif
273
274         if (flags & CMD_ASYNC)
275                 cmd.meta.u.callback = iwl4965_lq_sync_callback;
276
277         if (iwl4965_is_associated(priv) && priv->assoc_station_added &&
278             priv->lq_mngr.lq_ready)
279                 return  iwl4965_send_cmd(priv, &cmd);
280
281         return 0;
282 }
283
284 static void rs_rate_scale_clear_window(struct iwl4965_rate_scale_data *window)
285 {
286         window->data = 0;
287         window->success_counter = 0;
288         window->success_ratio = IWL_INVALID_VALUE;
289         window->counter = 0;
290         window->average_tpt = IWL_INVALID_VALUE;
291         window->stamp = 0;
292 }
293
294 #ifdef CONFIG_IWL4965_HT
295 /*
296  *      removes the old data from the statistics. All data that is older than
297  *      TID_MAX_TIME_DIFF, will be deleted.
298  */
299 static void rs_tl_rm_old_stats(struct iwl4965_traffic_load *tl, u32 curr_time)
300 {
301         /* The oldest age we want to keep */
302         u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
303
304         while (tl->queue_count &&
305                (tl->time_stamp < oldest_time)) {
306                 tl->total -= tl->packet_count[tl->head];
307                 tl->packet_count[tl->head] = 0;
308                 tl->time_stamp += TID_QUEUE_CELL_SPACING;
309                 tl->queue_count--;
310                 tl->head++;
311                 if (tl->head >= TID_QUEUE_MAX_SIZE)
312                         tl->head = 0;
313         }
314 }
315
316 /*
317  *      increment traffic load value for tid and also remove
318  *      any old values if passed the certain time period
319  */
320 static void rs_tl_add_packet(struct iwl4965_lq_sta *lq_data, u8 tid)
321 {
322         u32 curr_time = jiffies_to_msecs(jiffies);
323         u32 time_diff;
324         s32 index;
325         struct iwl4965_traffic_load *tl = NULL;
326
327         if (tid >= TID_MAX_LOAD_COUNT)
328                 return;
329
330         tl = &lq_data->load[tid];
331
332         curr_time -= curr_time % TID_ROUND_VALUE;
333
334         /* Happens only for the first packet. Initialize the data */
335         if (!(tl->queue_count)) {
336                 tl->total = 1;
337                 tl->time_stamp = curr_time;
338                 tl->queue_count = 1;
339                 tl->head = 0;
340                 tl->packet_count[0] = 1;
341                 return;
342         }
343
344         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
345         index = time_diff / TID_QUEUE_CELL_SPACING;
346
347         /* The history is too long: remove data that is older than */
348         /* TID_MAX_TIME_DIFF */
349         if (index >= TID_QUEUE_MAX_SIZE)
350                 rs_tl_rm_old_stats(tl, curr_time);
351
352         index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
353         tl->packet_count[index] = tl->packet_count[index] + 1;
354         tl->total = tl->total + 1;
355
356         if ((index + 1) > tl->queue_count)
357                 tl->queue_count = index + 1;
358 }
359
360 /*
361         get the traffic load value for tid
362 */
363 static u32 rs_tl_get_load(struct iwl4965_lq_sta *lq_data, u8 tid)
364 {
365         u32 curr_time = jiffies_to_msecs(jiffies);
366         u32 time_diff;
367         s32 index;
368         struct iwl4965_traffic_load *tl = NULL;
369
370         if (tid >= TID_MAX_LOAD_COUNT)
371                 return 0;
372
373         tl = &(lq_data->load[tid]);
374
375         curr_time -= curr_time % TID_ROUND_VALUE;
376
377         if (!(tl->queue_count))
378                 return 0;
379
380         time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
381         index = time_diff / TID_QUEUE_CELL_SPACING;
382
383         /* The history is too long: remove data that is older than */
384         /* TID_MAX_TIME_DIFF */
385         if (index >= TID_QUEUE_MAX_SIZE)
386                 rs_tl_rm_old_stats(tl, curr_time);
387
388         return tl->total;
389 }
390
391 static void rs_tl_turn_on_agg_for_tid(struct iwl4965_priv *priv,
392                                 struct iwl4965_lq_sta *lq_data, u8 tid,
393                                 struct sta_info *sta)
394 {
395         unsigned long state;
396         DECLARE_MAC_BUF(mac);
397
398         spin_lock_bh(&sta->ampdu_mlme.ampdu_tx);
399         state = sta->ampdu_mlme.tid_tx[tid].state;
400         spin_unlock_bh(&sta->ampdu_mlme.ampdu_tx);
401
402         if (state == HT_AGG_STATE_IDLE &&
403             rs_tl_get_load(lq_data, tid) > IWL_AGG_LOAD_THRESHOLD) {
404                 IWL_DEBUG_HT("Starting Tx agg: STA: %s tid: %d\n",
405                                 print_mac(mac, sta->addr), tid);
406                 ieee80211_start_tx_ba_session(priv->hw, sta->addr, tid);
407         }
408 }
409
410 static void rs_tl_turn_on_agg(struct iwl4965_priv *priv, u8 tid,
411                                 struct iwl4965_lq_sta *lq_data,
412                                 struct sta_info *sta)
413 {
414         if ((tid < TID_MAX_LOAD_COUNT))
415                 rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
416         else if (tid == IWL_AGG_ALL_TID)
417                 for (tid = 0; tid < TID_MAX_LOAD_COUNT; tid++)
418                         rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
419 }
420
421 #endif /* CONFIG_IWLWIFI_HT */
422
423 /**
424  * rs_collect_tx_data - Update the success/failure sliding window
425  *
426  * We keep a sliding window of the last 62 packets transmitted
427  * at this rate.  window->data contains the bitmask of successful
428  * packets.
429  */
430 static int rs_collect_tx_data(struct iwl4965_rate_scale_data *windows,
431                               int scale_index, s32 tpt, int retries,
432                               int successes)
433 {
434         struct iwl4965_rate_scale_data *window = NULL;
435         u64 mask;
436         u8 win_size = IWL_RATE_MAX_WINDOW;
437         s32 fail_count;
438
439         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
440                 return -EINVAL;
441
442         /* Select data for current tx bit rate */
443         window = &(windows[scale_index]);
444
445         /*
446          * Keep track of only the latest 62 tx frame attempts in this rate's
447          * history window; anything older isn't really relevant any more.
448          * If we have filled up the sliding window, drop the oldest attempt;
449          * if the oldest attempt (highest bit in bitmap) shows "success",
450          * subtract "1" from the success counter (this is the main reason
451          * we keep these bitmaps!).
452          */
453         while (retries > 0) {
454                 if (window->counter >= win_size) {
455                         window->counter = win_size - 1;
456                         mask = 1;
457                         mask = (mask << (win_size - 1));
458                         if (window->data & mask) {
459                                 window->data &= ~mask;
460                                 window->success_counter =
461                                         window->success_counter - 1;
462                         }
463                 }
464
465                 /* Increment frames-attempted counter */
466                 window->counter++;
467
468                 /* Shift bitmap by one frame (throw away oldest history),
469                  * OR in "1", and increment "success" if this
470                  * frame was successful. */
471                 mask = window->data;
472                 window->data = (mask << 1);
473                 if (successes > 0) {
474                         window->success_counter = window->success_counter + 1;
475                         window->data |= 0x1;
476                         successes--;
477                 }
478
479                 retries--;
480         }
481
482         /* Calculate current success ratio, avoid divide-by-0! */
483         if (window->counter > 0)
484                 window->success_ratio = 128 * (100 * window->success_counter)
485                                         / window->counter;
486         else
487                 window->success_ratio = IWL_INVALID_VALUE;
488
489         fail_count = window->counter - window->success_counter;
490
491         /* Calculate average throughput, if we have enough history. */
492         if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
493             (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
494                 window->average_tpt = (window->success_ratio * tpt + 64) / 128;
495         else
496                 window->average_tpt = IWL_INVALID_VALUE;
497
498         /* Tag this window as having been updated */
499         window->stamp = jiffies;
500
501         return 0;
502 }
503
504 /*
505  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
506  */
507 static void rs_mcs_from_tbl(struct iwl4965_rate *mcs_rate,
508                            struct iwl4965_scale_tbl_info *tbl,
509                            int index, u8 use_green)
510 {
511         if (is_legacy(tbl->lq_type)) {
512                 mcs_rate->rate_n_flags = iwl4965_rates[index].plcp;
513                 if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
514                         mcs_rate->rate_n_flags |= RATE_MCS_CCK_MSK;
515
516         } else if (is_siso(tbl->lq_type)) {
517                 if (index > IWL_LAST_OFDM_RATE)
518                         index = IWL_LAST_OFDM_RATE;
519                  mcs_rate->rate_n_flags = iwl4965_rates[index].plcp_siso |
520                                           RATE_MCS_HT_MSK;
521         } else {
522                 if (index > IWL_LAST_OFDM_RATE)
523                         index = IWL_LAST_OFDM_RATE;
524                 mcs_rate->rate_n_flags = iwl4965_rates[index].plcp_mimo |
525                                          RATE_MCS_HT_MSK;
526         }
527
528         switch (tbl->antenna_type) {
529         case ANT_BOTH:
530                 mcs_rate->rate_n_flags |= RATE_MCS_ANT_AB_MSK;
531                 break;
532         case ANT_MAIN:
533                 mcs_rate->rate_n_flags |= RATE_MCS_ANT_A_MSK;
534                 break;
535         case ANT_AUX:
536                 mcs_rate->rate_n_flags |= RATE_MCS_ANT_B_MSK;
537                 break;
538         case ANT_NONE:
539                 break;
540         }
541
542         if (is_legacy(tbl->lq_type))
543                 return;
544
545         if (tbl->is_fat) {
546                 if (tbl->is_dup)
547                         mcs_rate->rate_n_flags |= RATE_MCS_DUP_MSK;
548                 else
549                         mcs_rate->rate_n_flags |= RATE_MCS_FAT_MSK;
550         }
551         if (tbl->is_SGI)
552                 mcs_rate->rate_n_flags |= RATE_MCS_SGI_MSK;
553
554         if (use_green) {
555                 mcs_rate->rate_n_flags |= RATE_MCS_GF_MSK;
556                 if (is_siso(tbl->lq_type))
557                         mcs_rate->rate_n_flags &= ~RATE_MCS_SGI_MSK;
558         }
559 }
560
561 /*
562  * Interpret uCode API's rate_n_flags format,
563  * fill "search" or "active" tx mode table.
564  */
565 static int rs_get_tbl_info_from_mcs(const struct iwl4965_rate *mcs_rate,
566                                     enum ieee80211_band band,
567                                     struct iwl4965_scale_tbl_info *tbl,
568                                     int *rate_idx)
569 {
570         int index;
571         u32 ant_msk;
572
573         index = iwl4965_hwrate_to_plcp_idx(mcs_rate->rate_n_flags);
574
575         if (index  == IWL_RATE_INVALID) {
576                 *rate_idx = -1;
577                 return -EINVAL;
578         }
579         tbl->is_SGI = 0;        /* default legacy setup */
580         tbl->is_fat = 0;
581         tbl->is_dup = 0;
582         tbl->antenna_type = ANT_BOTH;   /* default MIMO setup */
583
584         /* legacy rate format */
585         if (!(mcs_rate->rate_n_flags & RATE_MCS_HT_MSK)) {
586                 ant_msk = (mcs_rate->rate_n_flags & RATE_MCS_ANT_AB_MSK);
587
588                 if (ant_msk == RATE_MCS_ANT_AB_MSK)
589                         tbl->lq_type = LQ_NONE;
590                 else {
591
592                         if (band == IEEE80211_BAND_5GHZ)
593                                 tbl->lq_type = LQ_A;
594                         else
595                                 tbl->lq_type = LQ_G;
596
597                         if (mcs_rate->rate_n_flags & RATE_MCS_ANT_A_MSK)
598                                 tbl->antenna_type = ANT_MAIN;
599                         else
600                                 tbl->antenna_type = ANT_AUX;
601                 }
602                 *rate_idx = index;
603
604         /* HT rate format, SISO (might be 20 MHz legacy or 40 MHz fat width) */
605         } else if (iwl4965_rate_get_rate(mcs_rate->rate_n_flags)
606                                         <= IWL_RATE_SISO_60M_PLCP) {
607                 tbl->lq_type = LQ_SISO;
608
609                 ant_msk = (mcs_rate->rate_n_flags & RATE_MCS_ANT_AB_MSK);
610                 if (ant_msk == RATE_MCS_ANT_AB_MSK)
611                         tbl->lq_type = LQ_NONE;
612                 else {
613                         if (mcs_rate->rate_n_flags & RATE_MCS_ANT_A_MSK)
614                                 tbl->antenna_type = ANT_MAIN;
615                         else
616                                 tbl->antenna_type = ANT_AUX;
617                 }
618                 if (mcs_rate->rate_n_flags & RATE_MCS_SGI_MSK)
619                         tbl->is_SGI = 1;
620
621                 if ((mcs_rate->rate_n_flags & RATE_MCS_FAT_MSK) ||
622                     (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK))
623                         tbl->is_fat = 1;
624
625                 if (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK)
626                         tbl->is_dup = 1;
627
628                 *rate_idx = index;
629
630         /* HT rate format, MIMO (might be 20 MHz legacy or 40 MHz fat width) */
631         } else {
632                 tbl->lq_type = LQ_MIMO;
633                 if (mcs_rate->rate_n_flags & RATE_MCS_SGI_MSK)
634                         tbl->is_SGI = 1;
635
636                 if ((mcs_rate->rate_n_flags & RATE_MCS_FAT_MSK) ||
637                     (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK))
638                         tbl->is_fat = 1;
639
640                 if (mcs_rate->rate_n_flags & RATE_MCS_DUP_MSK)
641                         tbl->is_dup = 1;
642                 *rate_idx = index;
643         }
644         return 0;
645 }
646
647 static inline void rs_toggle_antenna(struct iwl4965_rate *new_rate,
648                                      struct iwl4965_scale_tbl_info *tbl)
649 {
650         if (tbl->antenna_type == ANT_AUX) {
651                 tbl->antenna_type = ANT_MAIN;
652                 new_rate->rate_n_flags &= ~RATE_MCS_ANT_B_MSK;
653                 new_rate->rate_n_flags |= RATE_MCS_ANT_A_MSK;
654         } else {
655                 tbl->antenna_type = ANT_AUX;
656                 new_rate->rate_n_flags &= ~RATE_MCS_ANT_A_MSK;
657                 new_rate->rate_n_flags |= RATE_MCS_ANT_B_MSK;
658         }
659 }
660
661 static inline u8 rs_use_green(struct iwl4965_priv *priv,
662                               struct ieee80211_conf *conf)
663 {
664 #ifdef CONFIG_IWL4965_HT
665         return ((conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) &&
666                 priv->current_ht_config.is_green_field &&
667                 !priv->current_ht_config.non_GF_STA_present);
668 #endif  /* CONFIG_IWL4965_HT */
669         return 0;
670 }
671
672 /**
673  * rs_get_supported_rates - get the available rates
674  *
675  * if management frame or broadcast frame only return
676  * basic available rates.
677  *
678  */
679 static void rs_get_supported_rates(struct iwl4965_lq_sta *lq_sta,
680                                    struct ieee80211_hdr *hdr,
681                                    enum iwl4965_table_type rate_type,
682                                    u16 *data_rate)
683 {
684         if (is_legacy(rate_type))
685                 *data_rate = lq_sta->active_rate;
686         else {
687                 if (is_siso(rate_type))
688                         *data_rate = lq_sta->active_siso_rate;
689                 else
690                         *data_rate = lq_sta->active_mimo_rate;
691         }
692
693         if (hdr && is_multicast_ether_addr(hdr->addr1) &&
694             lq_sta->active_rate_basic) {
695                 *data_rate = lq_sta->active_rate_basic;
696         }
697 }
698
699 static u16 rs_get_adjacent_rate(u8 index, u16 rate_mask, int rate_type)
700 {
701         u8 high = IWL_RATE_INVALID;
702         u8 low = IWL_RATE_INVALID;
703
704         /* 802.11A or ht walks to the next literal adjacent rate in
705          * the rate table */
706         if (is_a_band(rate_type) || !is_legacy(rate_type)) {
707                 int i;
708                 u32 mask;
709
710                 /* Find the previous rate that is in the rate mask */
711                 i = index - 1;
712                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
713                         if (rate_mask & mask) {
714                                 low = i;
715                                 break;
716                         }
717                 }
718
719                 /* Find the next rate that is in the rate mask */
720                 i = index + 1;
721                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
722                         if (rate_mask & mask) {
723                                 high = i;
724                                 break;
725                         }
726                 }
727
728                 return (high << 8) | low;
729         }
730
731         low = index;
732         while (low != IWL_RATE_INVALID) {
733                 low = iwl4965_rates[low].prev_rs;
734                 if (low == IWL_RATE_INVALID)
735                         break;
736                 if (rate_mask & (1 << low))
737                         break;
738                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
739         }
740
741         high = index;
742         while (high != IWL_RATE_INVALID) {
743                 high = iwl4965_rates[high].next_rs;
744                 if (high == IWL_RATE_INVALID)
745                         break;
746                 if (rate_mask & (1 << high))
747                         break;
748                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
749         }
750
751         return (high << 8) | low;
752 }
753
754 static void rs_get_lower_rate(struct iwl4965_lq_sta *lq_sta,
755                              struct iwl4965_scale_tbl_info *tbl, u8 scale_index,
756                              u8 ht_possible, struct iwl4965_rate *mcs_rate)
757 {
758         s32 low;
759         u16 rate_mask;
760         u16 high_low;
761         u8 switch_to_legacy = 0;
762         u8 is_green = lq_sta->is_green;
763
764         /* check if we need to switch from HT to legacy rates.
765          * assumption is that mandatory rates (1Mbps or 6Mbps)
766          * are always supported (spec demand) */
767         if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
768                 switch_to_legacy = 1;
769                 scale_index = rs_ht_to_legacy[scale_index];
770                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
771                         tbl->lq_type = LQ_A;
772                 else
773                         tbl->lq_type = LQ_G;
774
775                 if ((tbl->antenna_type == ANT_BOTH) ||
776                     (tbl->antenna_type == ANT_NONE))
777                         tbl->antenna_type = ANT_MAIN;
778
779                 tbl->is_fat = 0;
780                 tbl->is_SGI = 0;
781         }
782
783         rs_get_supported_rates(lq_sta, NULL, tbl->lq_type, &rate_mask);
784
785         /* Mask with station rate restriction */
786         if (is_legacy(tbl->lq_type)) {
787                 /* supp_rates has no CCK bits in A mode */
788                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
789                         rate_mask  = (u16)(rate_mask &
790                            (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
791                 else
792                         rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
793         }
794
795         /* If we switched from HT to legacy, check current rate */
796         if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
797                 rs_mcs_from_tbl(mcs_rate, tbl, scale_index, is_green);
798                 return;
799         }
800
801         high_low = rs_get_adjacent_rate(scale_index, rate_mask, tbl->lq_type);
802         low = high_low & 0xff;
803
804         if (low != IWL_RATE_INVALID)
805                 rs_mcs_from_tbl(mcs_rate, tbl, low, is_green);
806         else
807                 rs_mcs_from_tbl(mcs_rate, tbl, scale_index, is_green);
808 }
809
810 /*
811  * mac80211 sends us Tx status
812  */
813 static void rs_tx_status(void *priv_rate, struct net_device *dev,
814                          struct sk_buff *skb,
815                          struct ieee80211_tx_status *tx_resp)
816 {
817         int status;
818         u8 retries;
819         int rs_index, index = 0;
820         struct iwl4965_lq_sta *lq_sta;
821         struct iwl4965_link_quality_cmd *table;
822         struct sta_info *sta;
823         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
824         struct iwl4965_priv *priv = (struct iwl4965_priv *)priv_rate;
825         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
826         struct ieee80211_hw *hw = local_to_hw(local);
827         struct iwl4965_rate_scale_data *window = NULL;
828         struct iwl4965_rate_scale_data *search_win = NULL;
829         struct iwl4965_rate tx_mcs;
830         struct iwl4965_scale_tbl_info tbl_type;
831         struct iwl4965_scale_tbl_info *curr_tbl, *search_tbl;
832         u8 active_index = 0;
833         u16 fc = le16_to_cpu(hdr->frame_control);
834         s32 tpt = 0;
835
836         IWL_DEBUG_RATE_LIMIT("get frame ack response, update rate scale window\n");
837
838         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1))
839                 return;
840
841         /* This packet was aggregated but doesn't carry rate scale info */
842         if ((tx_resp->control.flags & IEEE80211_TXCTL_AMPDU) &&
843             !(tx_resp->flags & IEEE80211_TX_STATUS_AMPDU))
844                 return;
845
846         retries = tx_resp->retry_count;
847
848         if (retries > 15)
849                 retries = 15;
850
851         rcu_read_lock();
852
853         sta = sta_info_get(local, hdr->addr1);
854
855         if (!sta || !sta->rate_ctrl_priv)
856                 goto out;
857
858
859         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
860
861         if (!priv->lq_mngr.lq_ready)
862                 goto out;
863
864         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
865             !lq_sta->ibss_sta_added)
866                 goto out;
867
868         table = &lq_sta->lq;
869         active_index = lq_sta->active_tbl;
870
871         /* Get mac80211 antenna info */
872         lq_sta->antenna =
873                 (lq_sta->valid_antenna & local->hw.conf.antenna_sel_tx);
874         if (!lq_sta->antenna)
875                 lq_sta->antenna = lq_sta->valid_antenna;
876
877         /* Ignore mac80211 antenna info for now */
878         lq_sta->antenna = lq_sta->valid_antenna;
879
880         curr_tbl = &(lq_sta->lq_info[active_index]);
881         search_tbl = &(lq_sta->lq_info[(1 - active_index)]);
882         window = (struct iwl4965_rate_scale_data *)
883             &(curr_tbl->win[0]);
884         search_win = (struct iwl4965_rate_scale_data *)
885             &(search_tbl->win[0]);
886
887         /*
888          * Ignore this Tx frame response if its initial rate doesn't match
889          * that of latest Link Quality command.  There may be stragglers
890          * from a previous Link Quality command, but we're no longer interested
891          * in those; they're either from the "active" mode while we're trying
892          * to check "search" mode, or a prior "search" mode after we've moved
893          * to a new "search" mode (which might become the new "active" mode).
894          */
895         tx_mcs.rate_n_flags = le32_to_cpu(table->rs_table[0].rate_n_flags);
896         rs_get_tbl_info_from_mcs(&tx_mcs, priv->band, &tbl_type, &rs_index);
897         if (priv->band == IEEE80211_BAND_5GHZ)
898                 rs_index -= IWL_FIRST_OFDM_RATE;
899
900         if ((tx_resp->control.tx_rate == NULL) ||
901             (tbl_type.is_SGI ^
902                 !!(tx_resp->control.flags & IEEE80211_TXCTL_SHORT_GI)) ||
903             (tbl_type.is_fat ^
904                 !!(tx_resp->control.flags & IEEE80211_TXCTL_40_MHZ_WIDTH)) ||
905             (tbl_type.is_dup ^
906                 !!(tx_resp->control.flags & IEEE80211_TXCTL_DUP_DATA)) ||
907             (tbl_type.antenna_type ^
908                 tx_resp->control.antenna_sel_tx) ||
909             (!!(tx_mcs.rate_n_flags & RATE_MCS_HT_MSK) ^
910                 !!(tx_resp->control.flags & IEEE80211_TXCTL_OFDM_HT)) ||
911             (!!(tx_mcs.rate_n_flags & RATE_MCS_GF_MSK) ^
912                 !!(tx_resp->control.flags & IEEE80211_TXCTL_GREEN_FIELD)) ||
913             (hw->wiphy->bands[priv->band]->bitrates[rs_index].bitrate !=
914                 tx_resp->control.tx_rate->bitrate)) {
915                 IWL_DEBUG_RATE("initial rate does not match 0x%x\n",
916                                 tx_mcs.rate_n_flags);
917                 goto out;
918         }
919
920         /* Update frame history window with "failure" for each Tx retry. */
921         while (retries) {
922                 /* Look up the rate and other info used for each tx attempt.
923                  * Each tx attempt steps one entry deeper in the rate table. */
924                 tx_mcs.rate_n_flags =
925                     le32_to_cpu(table->rs_table[index].rate_n_flags);
926                 rs_get_tbl_info_from_mcs(&tx_mcs, priv->band,
927                                           &tbl_type, &rs_index);
928
929                 /* If type matches "search" table,
930                  * add failure to "search" history */
931                 if ((tbl_type.lq_type == search_tbl->lq_type) &&
932                     (tbl_type.antenna_type == search_tbl->antenna_type) &&
933                     (tbl_type.is_SGI == search_tbl->is_SGI)) {
934                         if (search_tbl->expected_tpt)
935                                 tpt = search_tbl->expected_tpt[rs_index];
936                         else
937                                 tpt = 0;
938                         rs_collect_tx_data(search_win, rs_index, tpt, 1, 0);
939
940                 /* Else if type matches "current/active" table,
941                  * add failure to "current/active" history */
942                 } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
943                            (tbl_type.antenna_type == curr_tbl->antenna_type) &&
944                            (tbl_type.is_SGI == curr_tbl->is_SGI)) {
945                         if (curr_tbl->expected_tpt)
946                                 tpt = curr_tbl->expected_tpt[rs_index];
947                         else
948                                 tpt = 0;
949                         rs_collect_tx_data(window, rs_index, tpt, 1, 0);
950                 }
951
952                 /* If not searching for a new mode, increment failed counter
953                  * ... this helps determine when to start searching again */
954                 if (lq_sta->stay_in_tbl)
955                         lq_sta->total_failed++;
956                 --retries;
957                 index++;
958
959         }
960
961         /*
962          * Find (by rate) the history window to update with final Tx attempt;
963          * if Tx was successful first try, use original rate,
964          * else look up the rate that was, finally, successful.
965          */
966         tx_mcs.rate_n_flags = le32_to_cpu(table->rs_table[index].rate_n_flags);
967         rs_get_tbl_info_from_mcs(&tx_mcs, priv->band, &tbl_type, &rs_index);
968
969         /* Update frame history window with "success" if Tx got ACKed ... */
970         if (tx_resp->flags & IEEE80211_TX_STATUS_ACK)
971                 status = 1;
972         else
973                 status = 0;
974
975         /* If type matches "search" table,
976          * add final tx status to "search" history */
977         if ((tbl_type.lq_type == search_tbl->lq_type) &&
978             (tbl_type.antenna_type == search_tbl->antenna_type) &&
979             (tbl_type.is_SGI == search_tbl->is_SGI)) {
980                 if (search_tbl->expected_tpt)
981                         tpt = search_tbl->expected_tpt[rs_index];
982                 else
983                         tpt = 0;
984                 if (tx_resp->control.flags & IEEE80211_TXCTL_AMPDU)
985                         rs_collect_tx_data(search_win, rs_index, tpt,
986                                            tx_resp->ampdu_ack_len,
987                                            tx_resp->ampdu_ack_map);
988                 else
989                         rs_collect_tx_data(search_win, rs_index, tpt,
990                                            1, status);
991         /* Else if type matches "current/active" table,
992          * add final tx status to "current/active" history */
993         } else if ((tbl_type.lq_type == curr_tbl->lq_type) &&
994                    (tbl_type.antenna_type == curr_tbl->antenna_type) &&
995                    (tbl_type.is_SGI == curr_tbl->is_SGI)) {
996                 if (curr_tbl->expected_tpt)
997                         tpt = curr_tbl->expected_tpt[rs_index];
998                 else
999                         tpt = 0;
1000                 if (tx_resp->control.flags & IEEE80211_TXCTL_AMPDU)
1001                         rs_collect_tx_data(window, rs_index, tpt,
1002                                            tx_resp->ampdu_ack_len,
1003                                            tx_resp->ampdu_ack_map);
1004                 else
1005                         rs_collect_tx_data(window, rs_index, tpt,
1006                                            1, status);
1007         }
1008
1009         /* If not searching for new mode, increment success/failed counter
1010          * ... these help determine when to start searching again */
1011         if (lq_sta->stay_in_tbl) {
1012                 if (tx_resp->control.flags & IEEE80211_TXCTL_AMPDU) {
1013                         lq_sta->total_success += tx_resp->ampdu_ack_map;
1014                         lq_sta->total_failed +=
1015                              (tx_resp->ampdu_ack_len - tx_resp->ampdu_ack_map);
1016                 } else {
1017                         if (status)
1018                                 lq_sta->total_success++;
1019                         else
1020                                 lq_sta->total_failed++;
1021                 }
1022         }
1023
1024         /* See if there's a better rate or modulation mode to try. */
1025         rs_rate_scale_perform(priv, dev, hdr, sta);
1026 out:
1027         rcu_read_unlock();
1028         return;
1029 }
1030
1031 static u8 rs_is_ant_connected(u8 valid_antenna,
1032                               enum iwl4965_antenna_type antenna_type)
1033 {
1034         if (antenna_type == ANT_AUX)
1035                 return ((valid_antenna & 0x2) ? 1:0);
1036         else if (antenna_type == ANT_MAIN)
1037                 return ((valid_antenna & 0x1) ? 1:0);
1038         else if (antenna_type == ANT_BOTH)
1039                 return ((valid_antenna & 0x3) == 0x3);
1040
1041         return 1;
1042 }
1043
1044 static u8 rs_is_other_ant_connected(u8 valid_antenna,
1045                                     enum iwl4965_antenna_type antenna_type)
1046 {
1047         if (antenna_type == ANT_AUX)
1048                 return rs_is_ant_connected(valid_antenna, ANT_MAIN);
1049         else
1050                 return rs_is_ant_connected(valid_antenna, ANT_AUX);
1051
1052         return 0;
1053 }
1054
1055 /*
1056  * Begin a period of staying with a selected modulation mode.
1057  * Set "stay_in_tbl" flag to prevent any mode switches.
1058  * Set frame tx success limits according to legacy vs. high-throughput,
1059  * and reset overall (spanning all rates) tx success history statistics.
1060  * These control how long we stay using same modulation mode before
1061  * searching for a new mode.
1062  */
1063 static void rs_set_stay_in_table(u8 is_legacy,
1064                                  struct iwl4965_lq_sta *lq_sta)
1065 {
1066         IWL_DEBUG_HT("we are staying in the same table\n");
1067         lq_sta->stay_in_tbl = 1;        /* only place this gets set */
1068         if (is_legacy) {
1069                 lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
1070                 lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
1071                 lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
1072         } else {
1073                 lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
1074                 lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
1075                 lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
1076         }
1077         lq_sta->table_count = 0;
1078         lq_sta->total_failed = 0;
1079         lq_sta->total_success = 0;
1080 }
1081
1082 /*
1083  * Find correct throughput table for given mode of modulation
1084  */
1085 static void rs_get_expected_tpt_table(struct iwl4965_lq_sta *lq_sta,
1086                                       struct iwl4965_scale_tbl_info *tbl)
1087 {
1088         if (is_legacy(tbl->lq_type)) {
1089                 if (!is_a_band(tbl->lq_type))
1090                         tbl->expected_tpt = expected_tpt_G;
1091                 else
1092                         tbl->expected_tpt = expected_tpt_A;
1093         } else if (is_siso(tbl->lq_type)) {
1094                 if (tbl->is_fat && !lq_sta->is_dup)
1095                         if (tbl->is_SGI)
1096                                 tbl->expected_tpt = expected_tpt_siso40MHzSGI;
1097                         else
1098                                 tbl->expected_tpt = expected_tpt_siso40MHz;
1099                 else if (tbl->is_SGI)
1100                         tbl->expected_tpt = expected_tpt_siso20MHzSGI;
1101                 else
1102                         tbl->expected_tpt = expected_tpt_siso20MHz;
1103
1104         } else if (is_mimo(tbl->lq_type)) {
1105                 if (tbl->is_fat && !lq_sta->is_dup)
1106                         if (tbl->is_SGI)
1107                                 tbl->expected_tpt = expected_tpt_mimo40MHzSGI;
1108                         else
1109                                 tbl->expected_tpt = expected_tpt_mimo40MHz;
1110                 else if (tbl->is_SGI)
1111                         tbl->expected_tpt = expected_tpt_mimo20MHzSGI;
1112                 else
1113                         tbl->expected_tpt = expected_tpt_mimo20MHz;
1114         } else
1115                 tbl->expected_tpt = expected_tpt_G;
1116 }
1117
1118 #ifdef CONFIG_IWL4965_HT
1119 /*
1120  * Find starting rate for new "search" high-throughput mode of modulation.
1121  * Goal is to find lowest expected rate (under perfect conditions) that is
1122  * above the current measured throughput of "active" mode, to give new mode
1123  * a fair chance to prove itself without too many challenges.
1124  *
1125  * This gets called when transitioning to more aggressive modulation
1126  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1127  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1128  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1129  * bit rate will typically need to increase, but not if performance was bad.
1130  */
1131 static s32 rs_get_best_rate(struct iwl4965_priv *priv,
1132                             struct iwl4965_lq_sta *lq_sta,
1133                             struct iwl4965_scale_tbl_info *tbl, /* "search" */
1134                             u16 rate_mask, s8 index, s8 rate)
1135 {
1136         /* "active" values */
1137         struct iwl4965_scale_tbl_info *active_tbl =
1138             &(lq_sta->lq_info[lq_sta->active_tbl]);
1139         s32 active_sr = active_tbl->win[index].success_ratio;
1140         s32 active_tpt = active_tbl->expected_tpt[index];
1141
1142         /* expected "search" throughput */
1143         s32 *tpt_tbl = tbl->expected_tpt;
1144
1145         s32 new_rate, high, low, start_hi;
1146         u16 high_low;
1147
1148         new_rate = high = low = start_hi = IWL_RATE_INVALID;
1149
1150         for (; ;) {
1151                 high_low = rs_get_adjacent_rate(rate, rate_mask, tbl->lq_type);
1152
1153                 low = high_low & 0xff;
1154                 high = (high_low >> 8) & 0xff;
1155
1156                 /*
1157                  * Lower the "search" bit rate, to give new "search" mode
1158                  * approximately the same throughput as "active" if:
1159                  *
1160                  * 1) "Active" mode has been working modestly well (but not
1161                  *    great), and expected "search" throughput (under perfect
1162                  *    conditions) at candidate rate is above the actual
1163                  *    measured "active" throughput (but less than expected
1164                  *    "active" throughput under perfect conditions).
1165                  * OR
1166                  * 2) "Active" mode has been working perfectly or very well
1167                  *    and expected "search" throughput (under perfect
1168                  *    conditions) at candidate rate is above expected
1169                  *    "active" throughput (under perfect conditions).
1170                  */
1171                 if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1172                      ((active_sr > IWL_RATE_DECREASE_TH) &&
1173                       (active_sr <= IWL_RATE_HIGH_TH) &&
1174                       (tpt_tbl[rate] <= active_tpt))) ||
1175                     ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1176                      (tpt_tbl[rate] > active_tpt))) {
1177
1178                         /* (2nd or later pass)
1179                          * If we've already tried to raise the rate, and are
1180                          * now trying to lower it, use the higher rate. */
1181                         if (start_hi != IWL_RATE_INVALID) {
1182                                 new_rate = start_hi;
1183                                 break;
1184                         }
1185
1186                         new_rate = rate;
1187
1188                         /* Loop again with lower rate */
1189                         if (low != IWL_RATE_INVALID)
1190                                 rate = low;
1191
1192                         /* Lower rate not available, use the original */
1193                         else
1194                                 break;
1195
1196                 /* Else try to raise the "search" rate to match "active" */
1197                 } else {
1198                         /* (2nd or later pass)
1199                          * If we've already tried to lower the rate, and are
1200                          * now trying to raise it, use the lower rate. */
1201                         if (new_rate != IWL_RATE_INVALID)
1202                                 break;
1203
1204                         /* Loop again with higher rate */
1205                         else if (high != IWL_RATE_INVALID) {
1206                                 start_hi = high;
1207                                 rate = high;
1208
1209                         /* Higher rate not available, use the original */
1210                         } else {
1211                                 new_rate = rate;
1212                                 break;
1213                         }
1214                 }
1215         }
1216
1217         return new_rate;
1218 }
1219 #endif                          /* CONFIG_IWL4965_HT */
1220
1221 static inline u8 rs_is_both_ant_supp(u8 valid_antenna)
1222 {
1223         return (rs_is_ant_connected(valid_antenna, ANT_BOTH));
1224 }
1225
1226 /*
1227  * Set up search table for MIMO
1228  */
1229 static int rs_switch_to_mimo(struct iwl4965_priv *priv,
1230                              struct iwl4965_lq_sta *lq_sta,
1231                              struct ieee80211_conf *conf,
1232                              struct sta_info *sta,
1233                              struct iwl4965_scale_tbl_info *tbl, int index)
1234 {
1235 #ifdef CONFIG_IWL4965_HT
1236         u16 rate_mask;
1237         s32 rate;
1238         s8 is_green = lq_sta->is_green;
1239
1240         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1241             !sta->ht_info.ht_supported)
1242                 return -1;
1243
1244         IWL_DEBUG_HT("LQ: try to switch to MIMO\n");
1245         tbl->lq_type = LQ_MIMO;
1246         rs_get_supported_rates(lq_sta, NULL, tbl->lq_type,
1247                                 &rate_mask);
1248
1249         if (priv->current_ht_config.tx_mimo_ps_mode == IWL_MIMO_PS_STATIC)
1250                 return -1;
1251
1252         /* Need both Tx chains/antennas to support MIMO */
1253         if (!rs_is_both_ant_supp(lq_sta->antenna))
1254                 return -1;
1255
1256         tbl->is_dup = lq_sta->is_dup;
1257         tbl->action = 0;
1258         if (priv->current_ht_config.supported_chan_width
1259             == IWL_CHANNEL_WIDTH_40MHZ)
1260                 tbl->is_fat = 1;
1261         else
1262                 tbl->is_fat = 0;
1263
1264         if (tbl->is_fat) {
1265                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1266                         tbl->is_SGI = 1;
1267                 else
1268                         tbl->is_SGI = 0;
1269         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1270                 tbl->is_SGI = 1;
1271         else
1272                 tbl->is_SGI = 0;
1273
1274         rs_get_expected_tpt_table(lq_sta, tbl);
1275
1276         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index, index);
1277
1278         IWL_DEBUG_HT("LQ: MIMO best rate %d mask %X\n", rate, rate_mask);
1279         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask))
1280                 return -1;
1281         rs_mcs_from_tbl(&tbl->current_rate, tbl, rate, is_green);
1282
1283         IWL_DEBUG_HT("LQ: Switch to new mcs %X index is green %X\n",
1284                      tbl->current_rate.rate_n_flags, is_green);
1285         return 0;
1286 #else
1287         return -1;
1288 #endif  /*CONFIG_IWL4965_HT */
1289 }
1290
1291 /*
1292  * Set up search table for SISO
1293  */
1294 static int rs_switch_to_siso(struct iwl4965_priv *priv,
1295                              struct iwl4965_lq_sta *lq_sta,
1296                              struct ieee80211_conf *conf,
1297                              struct sta_info *sta,
1298                              struct iwl4965_scale_tbl_info *tbl, int index)
1299 {
1300 #ifdef CONFIG_IWL4965_HT
1301         u16 rate_mask;
1302         u8 is_green = lq_sta->is_green;
1303         s32 rate;
1304
1305         IWL_DEBUG_HT("LQ: try to switch to SISO\n");
1306         if (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE) ||
1307             !sta->ht_info.ht_supported)
1308                 return -1;
1309
1310         tbl->is_dup = lq_sta->is_dup;
1311         tbl->lq_type = LQ_SISO;
1312         tbl->action = 0;
1313         rs_get_supported_rates(lq_sta, NULL, tbl->lq_type,
1314                                 &rate_mask);
1315
1316         if (priv->current_ht_config.supported_chan_width
1317             == IWL_CHANNEL_WIDTH_40MHZ)
1318                 tbl->is_fat = 1;
1319         else
1320                 tbl->is_fat = 0;
1321
1322         if (tbl->is_fat) {
1323                 if (priv->current_ht_config.sgf & HT_SHORT_GI_40MHZ_ONLY)
1324                         tbl->is_SGI = 1;
1325                 else
1326                         tbl->is_SGI = 0;
1327         } else if (priv->current_ht_config.sgf & HT_SHORT_GI_20MHZ_ONLY)
1328                 tbl->is_SGI = 1;
1329         else
1330                 tbl->is_SGI = 0;
1331
1332         if (is_green)
1333                 tbl->is_SGI = 0;
1334
1335         rs_get_expected_tpt_table(lq_sta, tbl);
1336         rate = rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index, index);
1337
1338         IWL_DEBUG_HT("LQ: get best rate %d mask %X\n", rate, rate_mask);
1339         if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1340                 IWL_DEBUG_HT("can not switch with index %d rate mask %x\n",
1341                              rate, rate_mask);
1342                 return -1;
1343         }
1344         rs_mcs_from_tbl(&tbl->current_rate, tbl, rate, is_green);
1345         IWL_DEBUG_HT("LQ: Switch to new mcs %X index is green %X\n",
1346                      tbl->current_rate.rate_n_flags, is_green);
1347         return 0;
1348 #else
1349         return -1;
1350
1351 #endif  /*CONFIG_IWL4965_HT */
1352 }
1353
1354 /*
1355  * Try to switch to new modulation mode from legacy
1356  */
1357 static int rs_move_legacy_other(struct iwl4965_priv *priv,
1358                                 struct iwl4965_lq_sta *lq_sta,
1359                                 struct ieee80211_conf *conf,
1360                                 struct sta_info *sta,
1361                                 int index)
1362 {
1363         int ret = 0;
1364         struct iwl4965_scale_tbl_info *tbl =
1365             &(lq_sta->lq_info[lq_sta->active_tbl]);
1366         struct iwl4965_scale_tbl_info *search_tbl =
1367             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1368         struct iwl4965_rate_scale_data *window = &(tbl->win[index]);
1369         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1370                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1371         u8 start_action = tbl->action;
1372
1373         for (; ;) {
1374                 switch (tbl->action) {
1375                 case IWL_LEGACY_SWITCH_ANTENNA:
1376                         IWL_DEBUG_HT("LQ Legacy switch Antenna\n");
1377
1378                         search_tbl->lq_type = LQ_NONE;
1379                         lq_sta->action_counter++;
1380
1381                         /* Don't change antenna if success has been great */
1382                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1383                                 break;
1384
1385                         /* Don't change antenna if other one is not connected */
1386                         if (!rs_is_other_ant_connected(lq_sta->antenna,
1387                                                         tbl->antenna_type))
1388                                 break;
1389
1390                         /* Set up search table to try other antenna */
1391                         memcpy(search_tbl, tbl, sz);
1392
1393                         rs_toggle_antenna(&(search_tbl->current_rate),
1394                                            search_tbl);
1395                         rs_get_expected_tpt_table(lq_sta, search_tbl);
1396                         lq_sta->search_better_tbl = 1;
1397                         goto out;
1398
1399                 case IWL_LEGACY_SWITCH_SISO:
1400                         IWL_DEBUG_HT("LQ: Legacy switch to SISO\n");
1401
1402                         /* Set up search table to try SISO */
1403                         memcpy(search_tbl, tbl, sz);
1404                         search_tbl->lq_type = LQ_SISO;
1405                         search_tbl->is_SGI = 0;
1406                         search_tbl->is_fat = 0;
1407                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1408                                                  search_tbl, index);
1409                         if (!ret) {
1410                                 lq_sta->search_better_tbl = 1;
1411                                 lq_sta->action_counter = 0;
1412                                 goto out;
1413                         }
1414
1415                         break;
1416                 case IWL_LEGACY_SWITCH_MIMO:
1417                         IWL_DEBUG_HT("LQ: Legacy switch MIMO\n");
1418
1419                         /* Set up search table to try MIMO */
1420                         memcpy(search_tbl, tbl, sz);
1421                         search_tbl->lq_type = LQ_MIMO;
1422                         search_tbl->is_SGI = 0;
1423                         search_tbl->is_fat = 0;
1424                         search_tbl->antenna_type = ANT_BOTH;
1425                         ret = rs_switch_to_mimo(priv, lq_sta, conf, sta,
1426                                                  search_tbl, index);
1427                         if (!ret) {
1428                                 lq_sta->search_better_tbl = 1;
1429                                 lq_sta->action_counter = 0;
1430                                 goto out;
1431                         }
1432                         break;
1433                 }
1434                 tbl->action++;
1435                 if (tbl->action > IWL_LEGACY_SWITCH_MIMO)
1436                         tbl->action = IWL_LEGACY_SWITCH_ANTENNA;
1437
1438                 if (tbl->action == start_action)
1439                         break;
1440
1441         }
1442         return 0;
1443
1444  out:
1445         tbl->action++;
1446         if (tbl->action > IWL_LEGACY_SWITCH_MIMO)
1447                 tbl->action = IWL_LEGACY_SWITCH_ANTENNA;
1448         return 0;
1449
1450 }
1451
1452 /*
1453  * Try to switch to new modulation mode from SISO
1454  */
1455 static int rs_move_siso_to_other(struct iwl4965_priv *priv,
1456                                  struct iwl4965_lq_sta *lq_sta,
1457                                  struct ieee80211_conf *conf,
1458                                  struct sta_info *sta,
1459                                  int index)
1460 {
1461         int ret;
1462         u8 is_green = lq_sta->is_green;
1463         struct iwl4965_scale_tbl_info *tbl =
1464             &(lq_sta->lq_info[lq_sta->active_tbl]);
1465         struct iwl4965_scale_tbl_info *search_tbl =
1466             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1467         struct iwl4965_rate_scale_data *window = &(tbl->win[index]);
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
1472         for (;;) {
1473                 lq_sta->action_counter++;
1474                 switch (tbl->action) {
1475                 case IWL_SISO_SWITCH_ANTENNA:
1476                         IWL_DEBUG_HT("LQ: SISO SWITCH ANTENNA SISO\n");
1477                         search_tbl->lq_type = LQ_NONE;
1478                         if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1479                                 break;
1480                         if (!rs_is_other_ant_connected(lq_sta->antenna,
1481                                                        tbl->antenna_type))
1482                                 break;
1483
1484                         memcpy(search_tbl, tbl, sz);
1485                         search_tbl->action = IWL_SISO_SWITCH_MIMO;
1486                         rs_toggle_antenna(&(search_tbl->current_rate),
1487                                            search_tbl);
1488                         lq_sta->search_better_tbl = 1;
1489
1490                         goto out;
1491
1492                 case IWL_SISO_SWITCH_MIMO:
1493                         IWL_DEBUG_HT("LQ: SISO SWITCH TO MIMO FROM SISO\n");
1494                         memcpy(search_tbl, tbl, sz);
1495                         search_tbl->lq_type = LQ_MIMO;
1496                         search_tbl->is_SGI = 0;
1497                         search_tbl->is_fat = 0;
1498                         search_tbl->antenna_type = ANT_BOTH;
1499                         ret = rs_switch_to_mimo(priv, lq_sta, conf, sta,
1500                                                  search_tbl, index);
1501                         if (!ret) {
1502                                 lq_sta->search_better_tbl = 1;
1503                                 goto out;
1504                         }
1505                         break;
1506                 case IWL_SISO_SWITCH_GI:
1507                         IWL_DEBUG_HT("LQ: SISO SWITCH TO GI\n");
1508
1509                         memcpy(search_tbl, tbl, sz);
1510                         search_tbl->action = 0;
1511                         if (search_tbl->is_SGI)
1512                                 search_tbl->is_SGI = 0;
1513                         else if (!is_green)
1514                                 search_tbl->is_SGI = 1;
1515                         else
1516                                 break;
1517                         lq_sta->search_better_tbl = 1;
1518                         if ((tbl->lq_type == LQ_SISO) &&
1519                             (tbl->is_SGI)) {
1520                                 s32 tpt = lq_sta->last_tpt / 100;
1521                                 if (((!tbl->is_fat) &&
1522                                      (tpt >= expected_tpt_siso20MHz[index])) ||
1523                                     ((tbl->is_fat) &&
1524                                      (tpt >= expected_tpt_siso40MHz[index])))
1525                                         lq_sta->search_better_tbl = 0;
1526                         }
1527                         rs_get_expected_tpt_table(lq_sta, search_tbl);
1528                         rs_mcs_from_tbl(&search_tbl->current_rate,
1529                                              search_tbl, index, is_green);
1530                         goto out;
1531                 }
1532                 tbl->action++;
1533                 if (tbl->action > IWL_SISO_SWITCH_GI)
1534                         tbl->action = IWL_SISO_SWITCH_ANTENNA;
1535
1536                 if (tbl->action == start_action)
1537                         break;
1538         }
1539         return 0;
1540
1541  out:
1542         tbl->action++;
1543         if (tbl->action > IWL_SISO_SWITCH_GI)
1544                 tbl->action = IWL_SISO_SWITCH_ANTENNA;
1545         return 0;
1546 }
1547
1548 /*
1549  * Try to switch to new modulation mode from MIMO
1550  */
1551 static int rs_move_mimo_to_other(struct iwl4965_priv *priv,
1552                                  struct iwl4965_lq_sta *lq_sta,
1553                                  struct ieee80211_conf *conf,
1554                                  struct sta_info *sta,
1555                                  int index)
1556 {
1557         int ret;
1558         s8 is_green = lq_sta->is_green;
1559         struct iwl4965_scale_tbl_info *tbl =
1560             &(lq_sta->lq_info[lq_sta->active_tbl]);
1561         struct iwl4965_scale_tbl_info *search_tbl =
1562             &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1563         u32 sz = (sizeof(struct iwl4965_scale_tbl_info) -
1564                   (sizeof(struct iwl4965_rate_scale_data) * IWL_RATE_COUNT));
1565         u8 start_action = tbl->action;
1566
1567         for (;;) {
1568                 lq_sta->action_counter++;
1569                 switch (tbl->action) {
1570                 case IWL_MIMO_SWITCH_ANTENNA_A:
1571                 case IWL_MIMO_SWITCH_ANTENNA_B:
1572                         IWL_DEBUG_HT("LQ: MIMO SWITCH TO SISO\n");
1573
1574
1575                         /* Set up new search table for SISO */
1576                         memcpy(search_tbl, tbl, sz);
1577                         search_tbl->lq_type = LQ_SISO;
1578                         search_tbl->is_SGI = 0;
1579                         search_tbl->is_fat = 0;
1580                         if (tbl->action == IWL_MIMO_SWITCH_ANTENNA_A)
1581                                 search_tbl->antenna_type = ANT_MAIN;
1582                         else
1583                                 search_tbl->antenna_type = ANT_AUX;
1584
1585                         ret = rs_switch_to_siso(priv, lq_sta, conf, sta,
1586                                                  search_tbl, index);
1587                         if (!ret) {
1588                                 lq_sta->search_better_tbl = 1;
1589                                 goto out;
1590                         }
1591                         break;
1592
1593                 case IWL_MIMO_SWITCH_GI:
1594                         IWL_DEBUG_HT("LQ: MIMO SWITCH TO GI\n");
1595
1596                         /* Set up new search table for MIMO */
1597                         memcpy(search_tbl, tbl, sz);
1598                         search_tbl->lq_type = LQ_MIMO;
1599                         search_tbl->antenna_type = ANT_BOTH;
1600                         search_tbl->action = 0;
1601                         if (search_tbl->is_SGI)
1602                                 search_tbl->is_SGI = 0;
1603                         else
1604                                 search_tbl->is_SGI = 1;
1605                         lq_sta->search_better_tbl = 1;
1606
1607                         /*
1608                          * If active table already uses the fastest possible
1609                          * modulation (dual stream with short guard interval),
1610                          * and it's working well, there's no need to look
1611                          * for a better type of modulation!
1612                          */
1613                         if ((tbl->lq_type == LQ_MIMO) &&
1614                             (tbl->is_SGI)) {
1615                                 s32 tpt = lq_sta->last_tpt / 100;
1616                                 if (((!tbl->is_fat) &&
1617                                      (tpt >= expected_tpt_mimo20MHz[index])) ||
1618                                     ((tbl->is_fat) &&
1619                                      (tpt >= expected_tpt_mimo40MHz[index])))
1620                                         lq_sta->search_better_tbl = 0;
1621                         }
1622                         rs_get_expected_tpt_table(lq_sta, search_tbl);
1623                         rs_mcs_from_tbl(&search_tbl->current_rate,
1624                                              search_tbl, index, is_green);
1625                         goto out;
1626
1627                 }
1628                 tbl->action++;
1629                 if (tbl->action > IWL_MIMO_SWITCH_GI)
1630                         tbl->action = IWL_MIMO_SWITCH_ANTENNA_A;
1631
1632                 if (tbl->action == start_action)
1633                         break;
1634         }
1635
1636         return 0;
1637  out:
1638         tbl->action++;
1639         if (tbl->action > IWL_MIMO_SWITCH_GI)
1640                 tbl->action = IWL_MIMO_SWITCH_ANTENNA_A;
1641         return 0;
1642
1643 }
1644
1645 /*
1646  * Check whether we should continue using same modulation mode, or
1647  * begin search for a new mode, based on:
1648  * 1) # tx successes or failures while using this mode
1649  * 2) # times calling this function
1650  * 3) elapsed time in this mode (not used, for now)
1651  */
1652 static void rs_stay_in_table(struct iwl4965_lq_sta *lq_sta)
1653 {
1654         struct iwl4965_scale_tbl_info *tbl;
1655         int i;
1656         int active_tbl;
1657         int flush_interval_passed = 0;
1658
1659         active_tbl = lq_sta->active_tbl;
1660
1661         tbl = &(lq_sta->lq_info[active_tbl]);
1662
1663         /* If we've been disallowing search, see if we should now allow it */
1664         if (lq_sta->stay_in_tbl) {
1665
1666                 /* Elapsed time using current modulation mode */
1667                 if (lq_sta->flush_timer)
1668                         flush_interval_passed =
1669                             time_after(jiffies,
1670                                        (unsigned long)(lq_sta->flush_timer +
1671                                         IWL_RATE_SCALE_FLUSH_INTVL));
1672
1673                 /* For now, disable the elapsed time criterion */
1674                 flush_interval_passed = 0;
1675
1676                 /*
1677                  * Check if we should allow search for new modulation mode.
1678                  * If many frames have failed or succeeded, or we've used
1679                  * this same modulation for a long time, allow search, and
1680                  * reset history stats that keep track of whether we should
1681                  * allow a new search.  Also (below) reset all bitmaps and
1682                  * stats in active history.
1683                  */
1684                 if ((lq_sta->total_failed > lq_sta->max_failure_limit) ||
1685                     (lq_sta->total_success > lq_sta->max_success_limit) ||
1686                     ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1687                      && (flush_interval_passed))) {
1688                         IWL_DEBUG_HT("LQ: stay is expired %d %d %d\n:",
1689                                      lq_sta->total_failed,
1690                                      lq_sta->total_success,
1691                                      flush_interval_passed);
1692
1693                         /* Allow search for new mode */
1694                         lq_sta->stay_in_tbl = 0;        /* only place reset */
1695                         lq_sta->total_failed = 0;
1696                         lq_sta->total_success = 0;
1697                         lq_sta->flush_timer = 0;
1698
1699                 /*
1700                  * Else if we've used this modulation mode enough repetitions
1701                  * (regardless of elapsed time or success/failure), reset
1702                  * history bitmaps and rate-specific stats for all rates in
1703                  * active table.
1704                  */
1705                 } else {
1706                         lq_sta->table_count++;
1707                         if (lq_sta->table_count >=
1708                             lq_sta->table_count_limit) {
1709                                 lq_sta->table_count = 0;
1710
1711                                 IWL_DEBUG_HT("LQ: stay in table clear win\n");
1712                                 for (i = 0; i < IWL_RATE_COUNT; i++)
1713                                         rs_rate_scale_clear_window(
1714                                                 &(tbl->win[i]));
1715                         }
1716                 }
1717
1718                 /* If transitioning to allow "search", reset all history
1719                  * bitmaps and stats in active table (this will become the new
1720                  * "search" table). */
1721                 if (!lq_sta->stay_in_tbl) {
1722                         for (i = 0; i < IWL_RATE_COUNT; i++)
1723                                 rs_rate_scale_clear_window(&(tbl->win[i]));
1724                 }
1725         }
1726 }
1727
1728 /*
1729  * Do rate scaling and search for new modulation mode.
1730  */
1731 static void rs_rate_scale_perform(struct iwl4965_priv *priv,
1732                                   struct net_device *dev,
1733                                   struct ieee80211_hdr *hdr,
1734                                   struct sta_info *sta)
1735 {
1736         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1737         struct ieee80211_hw *hw = local_to_hw(local);
1738         struct ieee80211_conf *conf = &hw->conf;
1739         int low = IWL_RATE_INVALID;
1740         int high = IWL_RATE_INVALID;
1741         int index;
1742         int i;
1743         struct iwl4965_rate_scale_data *window = NULL;
1744         int current_tpt = IWL_INVALID_VALUE;
1745         int low_tpt = IWL_INVALID_VALUE;
1746         int high_tpt = IWL_INVALID_VALUE;
1747         u32 fail_count;
1748         s8 scale_action = 0;
1749         u16 fc, rate_mask;
1750         u8 update_lq = 0;
1751         struct iwl4965_lq_sta *lq_sta;
1752         struct iwl4965_scale_tbl_info *tbl, *tbl1;
1753         u16 rate_scale_index_msk = 0;
1754         struct iwl4965_rate mcs_rate;
1755         u8 is_green = 0;
1756         u8 active_tbl = 0;
1757         u8 done_search = 0;
1758         u16 high_low;
1759 #ifdef CONFIG_IWL4965_HT
1760         u8 tid = MAX_TID_COUNT;
1761         __le16 *qc;
1762 #endif
1763
1764         IWL_DEBUG_RATE("rate scale calculate new rate for skb\n");
1765
1766         fc = le16_to_cpu(hdr->frame_control);
1767         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1)) {
1768                 /* Send management frames and broadcast/multicast data using
1769                  * lowest rate. */
1770                 /* TODO: this could probably be improved.. */
1771                 return;
1772         }
1773
1774         if (!sta || !sta->rate_ctrl_priv)
1775                 return;
1776
1777         if (!priv->lq_mngr.lq_ready) {
1778                 IWL_DEBUG_RATE("still rate scaling not ready\n");
1779                 return;
1780         }
1781         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
1782
1783 #ifdef CONFIG_IWL4965_HT
1784         qc = ieee80211_get_qos_ctrl(hdr);
1785         if (qc) {
1786                 tid = (u8)(le16_to_cpu(*qc) & 0xf);
1787                 rs_tl_add_packet(lq_sta, tid);
1788         }
1789 #endif
1790         /*
1791          * Select rate-scale / modulation-mode table to work with in
1792          * the rest of this function:  "search" if searching for better
1793          * modulation mode, or "active" if doing rate scaling within a mode.
1794          */
1795         if (!lq_sta->search_better_tbl)
1796                 active_tbl = lq_sta->active_tbl;
1797         else
1798                 active_tbl = 1 - lq_sta->active_tbl;
1799
1800         tbl = &(lq_sta->lq_info[active_tbl]);
1801         is_green = lq_sta->is_green;
1802
1803         /* current tx rate */
1804         index = sta->last_txrate_idx;
1805
1806         IWL_DEBUG_RATE("Rate scale index %d for type %d\n", index,
1807                        tbl->lq_type);
1808
1809         /* rates available for this association, and for modulation mode */
1810         rs_get_supported_rates(lq_sta, hdr, tbl->lq_type,
1811                                 &rate_mask);
1812
1813         IWL_DEBUG_RATE("mask 0x%04X \n", rate_mask);
1814
1815         /* mask with station rate restriction */
1816         if (is_legacy(tbl->lq_type)) {
1817                 if (lq_sta->band == IEEE80211_BAND_5GHZ)
1818                         /* supp_rates has no CCK bits in A mode */
1819                         rate_scale_index_msk = (u16) (rate_mask &
1820                                 (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1821                 else
1822                         rate_scale_index_msk = (u16) (rate_mask &
1823                                                       lq_sta->supp_rates);
1824
1825         } else
1826                 rate_scale_index_msk = rate_mask;
1827
1828         if (!rate_scale_index_msk)
1829                 rate_scale_index_msk = rate_mask;
1830
1831         /* If current rate is no longer supported on current association,
1832          * or user changed preferences for rates, find a new supported rate. */
1833         if (index < 0 || !((1 << index) & rate_scale_index_msk)) {
1834                 index = IWL_INVALID_VALUE;
1835                 update_lq = 1;
1836
1837                 /* get the highest available rate */
1838                 for (i = 0; i <= IWL_RATE_COUNT; i++) {
1839                         if ((1 << i) & rate_scale_index_msk)
1840                                 index = i;
1841                 }
1842
1843                 if (index == IWL_INVALID_VALUE) {
1844                         IWL_WARNING("Can not find a suitable rate\n");
1845                         return;
1846                 }
1847         }
1848
1849         /* Get expected throughput table and history window for current rate */
1850         if (!tbl->expected_tpt)
1851                 rs_get_expected_tpt_table(lq_sta, tbl);
1852
1853         window = &(tbl->win[index]);
1854
1855         /*
1856          * If there is not enough history to calculate actual average
1857          * throughput, keep analyzing results of more tx frames, without
1858          * changing rate or mode (bypass most of the rest of this function).
1859          * Set up new rate table in uCode only if old rate is not supported
1860          * in current association (use new rate found above).
1861          */
1862         fail_count = window->counter - window->success_counter;
1863         if (((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1864              (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))
1865             || (tbl->expected_tpt == NULL)) {
1866                 IWL_DEBUG_RATE("LQ: still below TH succ %d total %d "
1867                                "for index %d\n",
1868                                window->success_counter, window->counter, index);
1869
1870                 /* Can't calculate this yet; not enough history */
1871                 window->average_tpt = IWL_INVALID_VALUE;
1872
1873                 /* Should we stay with this modulation mode,
1874                  * or search for a new one? */
1875                 rs_stay_in_table(lq_sta);
1876
1877                 /* Set up new rate table in uCode, if needed */
1878                 if (update_lq) {
1879                         rs_mcs_from_tbl(&mcs_rate, tbl, index, is_green);
1880                         rs_fill_link_cmd(lq_sta, &mcs_rate, &lq_sta->lq);
1881                         rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
1882                 }
1883                 goto out;
1884
1885         /* Else we have enough samples; calculate estimate of
1886          * actual average throughput */
1887         } else
1888                 window->average_tpt = ((window->success_ratio *
1889                                         tbl->expected_tpt[index] + 64) / 128);
1890
1891         /* If we are searching for better modulation mode, check success. */
1892         if (lq_sta->search_better_tbl) {
1893                 int success_limit = IWL_RATE_SCALE_SWITCH;
1894
1895                 /* If good success, continue using the "search" mode;
1896                  * no need to send new link quality command, since we're
1897                  * continuing to use the setup that we've been trying. */
1898                 if ((window->success_ratio > success_limit) ||
1899                     (window->average_tpt > lq_sta->last_tpt)) {
1900                         if (!is_legacy(tbl->lq_type)) {
1901                                 IWL_DEBUG_HT("LQ: we are switching to HT"
1902                                              " rate suc %d current tpt %d"
1903                                              " old tpt %d\n",
1904                                              window->success_ratio,
1905                                              window->average_tpt,
1906                                              lq_sta->last_tpt);
1907                                 lq_sta->enable_counter = 1;
1908                         }
1909                         /* Swap tables; "search" becomes "active" */
1910                         lq_sta->active_tbl = active_tbl;
1911                         current_tpt = window->average_tpt;
1912
1913                 /* Else poor success; go back to mode in "active" table */
1914                 } else {
1915                         /* Nullify "search" table */
1916                         tbl->lq_type = LQ_NONE;
1917
1918                         /* Revert to "active" table */
1919                         active_tbl = lq_sta->active_tbl;
1920                         tbl = &(lq_sta->lq_info[active_tbl]);
1921
1922                         /* Revert to "active" rate and throughput info */
1923                         index = iwl4965_hwrate_to_plcp_idx(
1924                                 tbl->current_rate.rate_n_flags);
1925                         current_tpt = lq_sta->last_tpt;
1926
1927                         /* Need to set up a new rate table in uCode */
1928                         update_lq = 1;
1929                         IWL_DEBUG_HT("XXY GO BACK TO OLD TABLE\n");
1930                 }
1931
1932                 /* Either way, we've made a decision; modulation mode
1933                  * search is done, allow rate adjustment next time. */
1934                 lq_sta->search_better_tbl = 0;
1935                 done_search = 1;        /* Don't switch modes below! */
1936                 goto lq_update;
1937         }
1938
1939         /* (Else) not in search of better modulation mode, try for better
1940          * starting rate, while staying in this mode. */
1941         high_low = rs_get_adjacent_rate(index, rate_scale_index_msk,
1942                                         tbl->lq_type);
1943         low = high_low & 0xff;
1944         high = (high_low >> 8) & 0xff;
1945
1946         /* Collect measured throughputs for current and adjacent rates */
1947         current_tpt = window->average_tpt;
1948         if (low != IWL_RATE_INVALID)
1949                 low_tpt = tbl->win[low].average_tpt;
1950         if (high != IWL_RATE_INVALID)
1951                 high_tpt = tbl->win[high].average_tpt;
1952
1953         /* Assume rate increase */
1954         scale_action = 1;
1955
1956         /* Too many failures, decrease rate */
1957         if ((window->success_ratio <= IWL_RATE_DECREASE_TH) ||
1958             (current_tpt == 0)) {
1959                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
1960                 scale_action = -1;
1961
1962         /* No throughput measured yet for adjacent rates; try increase. */
1963         } else if ((low_tpt == IWL_INVALID_VALUE) &&
1964                    (high_tpt == IWL_INVALID_VALUE))
1965                 scale_action = 1;
1966
1967         /* Both adjacent throughputs are measured, but neither one has better
1968          * throughput; we're using the best rate, don't change it! */
1969         else if ((low_tpt != IWL_INVALID_VALUE) &&
1970                  (high_tpt != IWL_INVALID_VALUE) &&
1971                  (low_tpt < current_tpt) &&
1972                  (high_tpt < current_tpt))
1973                 scale_action = 0;
1974
1975         /* At least one adjacent rate's throughput is measured,
1976          * and may have better performance. */
1977         else {
1978                 /* Higher adjacent rate's throughput is measured */
1979                 if (high_tpt != IWL_INVALID_VALUE) {
1980                         /* Higher rate has better throughput */
1981                         if (high_tpt > current_tpt)
1982                                 scale_action = 1;
1983                         else {
1984                                 IWL_DEBUG_RATE
1985                                     ("decrease rate because of high tpt\n");
1986                                 scale_action = -1;
1987                         }
1988
1989                 /* Lower adjacent rate's throughput is measured */
1990                 } else if (low_tpt != IWL_INVALID_VALUE) {
1991                         /* Lower rate has better throughput */
1992                         if (low_tpt > current_tpt) {
1993                                 IWL_DEBUG_RATE
1994                                     ("decrease rate because of low tpt\n");
1995                                 scale_action = -1;
1996                         } else
1997                                 scale_action = 1;
1998                 }
1999         }
2000
2001         /* Sanity check; asked for decrease, but success rate or throughput
2002          * has been good at old rate.  Don't change it. */
2003         if (scale_action == -1) {
2004                 if ((low != IWL_RATE_INVALID) &&
2005                     ((window->success_ratio > IWL_RATE_HIGH_TH) ||
2006                      (current_tpt > (100 * tbl->expected_tpt[low]))))
2007                         scale_action = 0;
2008
2009         /* Sanity check; asked for increase, but success rate has not been great
2010          * even at old rate, higher rate will be worse.  Don't change it. */
2011         } else if ((scale_action == 1) &&
2012                    (window->success_ratio < IWL_RATE_INCREASE_TH))
2013                 scale_action = 0;
2014
2015         switch (scale_action) {
2016         case -1:
2017                 /* Decrease starting rate, update uCode's rate table */
2018                 if (low != IWL_RATE_INVALID) {
2019                         update_lq = 1;
2020                         index = low;
2021                 }
2022                 break;
2023         case 1:
2024                 /* Increase starting rate, update uCode's rate table */
2025                 if (high != IWL_RATE_INVALID) {
2026                         update_lq = 1;
2027                         index = high;
2028                 }
2029
2030                 break;
2031         case 0:
2032                 /* No change */
2033         default:
2034                 break;
2035         }
2036
2037         IWL_DEBUG_HT("choose rate scale index %d action %d low %d "
2038                     "high %d type %d\n",
2039                      index, scale_action, low, high, tbl->lq_type);
2040
2041  lq_update:
2042         /* Replace uCode's rate table for the destination station. */
2043         if (update_lq) {
2044                 rs_mcs_from_tbl(&mcs_rate, tbl, index, is_green);
2045                 rs_fill_link_cmd(lq_sta, &mcs_rate, &lq_sta->lq);
2046                 rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2047         }
2048
2049         /* Should we stay with this modulation mode, or search for a new one? */
2050         rs_stay_in_table(lq_sta);
2051
2052         /*
2053          * Search for new modulation mode if we're:
2054          * 1)  Not changing rates right now
2055          * 2)  Not just finishing up a search
2056          * 3)  Allowing a new search
2057          */
2058         if (!update_lq && !done_search && !lq_sta->stay_in_tbl) {
2059                 /* Save current throughput to compare with "search" throughput*/
2060                 lq_sta->last_tpt = current_tpt;
2061
2062                 /* Select a new "search" modulation mode to try.
2063                  * If one is found, set up the new "search" table. */
2064                 if (is_legacy(tbl->lq_type))
2065                         rs_move_legacy_other(priv, lq_sta, conf, sta, index);
2066                 else if (is_siso(tbl->lq_type))
2067                         rs_move_siso_to_other(priv, lq_sta, conf, sta, index);
2068                 else
2069                         rs_move_mimo_to_other(priv, lq_sta, conf, sta, index);
2070
2071                 /* If new "search" mode was selected, set up in uCode table */
2072                 if (lq_sta->search_better_tbl) {
2073                         /* Access the "search" table, clear its history. */
2074                         tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2075                         for (i = 0; i < IWL_RATE_COUNT; i++)
2076                                 rs_rate_scale_clear_window(&(tbl->win[i]));
2077
2078                         /* Use new "search" start rate */
2079                         index = iwl4965_hwrate_to_plcp_idx(
2080                                         tbl->current_rate.rate_n_flags);
2081
2082                         IWL_DEBUG_HT("Switch current  mcs: %X index: %d\n",
2083                                      tbl->current_rate.rate_n_flags, index);
2084                         rs_fill_link_cmd(lq_sta, &tbl->current_rate,
2085                                          &lq_sta->lq);
2086                         rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2087                 }
2088
2089                 /* If the "active" (non-search) mode was legacy,
2090                  * and we've tried switching antennas,
2091                  * but we haven't been able to try HT modes (not available),
2092                  * stay with best antenna legacy modulation for a while
2093                  * before next round of mode comparisons. */
2094                 tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2095                 if (is_legacy(tbl1->lq_type) &&
2096 #ifdef CONFIG_IWL4965_HT
2097                    (!(conf->flags & IEEE80211_CONF_SUPPORT_HT_MODE)) &&
2098 #endif
2099                     (lq_sta->action_counter >= 1)) {
2100                         lq_sta->action_counter = 0;
2101                         IWL_DEBUG_HT("LQ: STAY in legacy table\n");
2102                         rs_set_stay_in_table(1, lq_sta);
2103                 }
2104
2105                 /* If we're in an HT mode, and all 3 mode switch actions
2106                  * have been tried and compared, stay in this best modulation
2107                  * mode for a while before next round of mode comparisons. */
2108                 if (lq_sta->enable_counter &&
2109                     (lq_sta->action_counter >= IWL_ACTION_LIMIT)) {
2110 #ifdef CONFIG_IWL4965_HT
2111                         if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2112                             (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2113                             (tid != MAX_TID_COUNT)) {
2114                                 IWL_DEBUG_HT("try to aggregate tid %d\n", tid);
2115                                 rs_tl_turn_on_agg(priv, tid, lq_sta, sta);
2116                         }
2117 #endif /*CONFIG_IWL4965_HT */
2118                         lq_sta->action_counter = 0;
2119                         rs_set_stay_in_table(0, lq_sta);
2120                 }
2121
2122         /*
2123          * Else, don't search for a new modulation mode.
2124          * Put new timestamp in stay-in-modulation-mode flush timer if:
2125          * 1)  Not changing rates right now
2126          * 2)  Not just finishing up a search
2127          * 3)  flush timer is empty
2128          */
2129         } else {
2130                 if ((!update_lq) && (!done_search) && (!lq_sta->flush_timer))
2131                         lq_sta->flush_timer = jiffies;
2132         }
2133
2134 out:
2135         rs_mcs_from_tbl(&tbl->current_rate, tbl, index, is_green);
2136         i = index;
2137         sta->last_txrate_idx = i;
2138
2139         /* sta->txrate_idx is an index to A mode rates which start
2140          * at IWL_FIRST_OFDM_RATE
2141          */
2142         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2143                 sta->txrate_idx = i - IWL_FIRST_OFDM_RATE;
2144         else
2145                 sta->txrate_idx = i;
2146
2147         return;
2148 }
2149
2150
2151 static void rs_initialize_lq(struct iwl4965_priv *priv,
2152                              struct ieee80211_conf *conf,
2153                              struct sta_info *sta)
2154 {
2155         int i;
2156         struct iwl4965_lq_sta *lq_sta;
2157         struct iwl4965_scale_tbl_info *tbl;
2158         u8 active_tbl = 0;
2159         int rate_idx;
2160         u8 use_green = rs_use_green(priv, conf);
2161         struct iwl4965_rate mcs_rate;
2162
2163         if (!sta || !sta->rate_ctrl_priv)
2164                 goto out;
2165
2166         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
2167         i = sta->last_txrate_idx;
2168
2169         if ((lq_sta->lq.sta_id == 0xff) &&
2170             (priv->iw_mode == IEEE80211_IF_TYPE_IBSS))
2171                 goto out;
2172
2173         if (!lq_sta->search_better_tbl)
2174                 active_tbl = lq_sta->active_tbl;
2175         else
2176                 active_tbl = 1 - lq_sta->active_tbl;
2177
2178         tbl = &(lq_sta->lq_info[active_tbl]);
2179
2180         if ((i < 0) || (i >= IWL_RATE_COUNT))
2181                 i = 0;
2182
2183         mcs_rate.rate_n_flags = iwl4965_rates[i].plcp ;
2184         mcs_rate.rate_n_flags |= RATE_MCS_ANT_B_MSK;
2185         mcs_rate.rate_n_flags &= ~RATE_MCS_ANT_A_MSK;
2186
2187         if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2188                 mcs_rate.rate_n_flags |= RATE_MCS_CCK_MSK;
2189
2190         tbl->antenna_type = ANT_AUX;
2191         rs_get_tbl_info_from_mcs(&mcs_rate, priv->band, tbl, &rate_idx);
2192         if (!rs_is_ant_connected(priv->valid_antenna, tbl->antenna_type))
2193             rs_toggle_antenna(&mcs_rate, tbl);
2194
2195         rs_mcs_from_tbl(&mcs_rate, tbl, rate_idx, use_green);
2196         tbl->current_rate.rate_n_flags = mcs_rate.rate_n_flags;
2197         rs_get_expected_tpt_table(lq_sta, tbl);
2198         rs_fill_link_cmd(lq_sta, &mcs_rate, &lq_sta->lq);
2199         rs_send_lq_cmd(priv, &lq_sta->lq, CMD_ASYNC);
2200  out:
2201         return;
2202 }
2203
2204 static void rs_get_rate(void *priv_rate, struct net_device *dev,
2205                         struct ieee80211_supported_band *sband,
2206                         struct sk_buff *skb,
2207                         struct rate_selection *sel)
2208 {
2209
2210         int i;
2211         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
2212         struct ieee80211_conf *conf = &local->hw.conf;
2213         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2214         struct sta_info *sta;
2215         u16 fc;
2216         struct iwl4965_priv *priv = (struct iwl4965_priv *)priv_rate;
2217         struct iwl4965_lq_sta *lq_sta;
2218
2219         IWL_DEBUG_RATE_LIMIT("rate scale calculate new rate for skb\n");
2220
2221         rcu_read_lock();
2222
2223         sta = sta_info_get(local, hdr->addr1);
2224
2225         /* Send management frames and broadcast/multicast data using lowest
2226          * rate. */
2227         fc = le16_to_cpu(hdr->frame_control);
2228         if (!ieee80211_is_data(fc) || is_multicast_ether_addr(hdr->addr1) ||
2229             !sta || !sta->rate_ctrl_priv) {
2230                 sel->rate = rate_lowest(local, sband, sta);
2231                 goto out;
2232         }
2233
2234         lq_sta = (struct iwl4965_lq_sta *)sta->rate_ctrl_priv;
2235         i = sta->last_txrate_idx;
2236
2237         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
2238             !lq_sta->ibss_sta_added) {
2239                 u8 sta_id = iwl4965_hw_find_station(priv, hdr->addr1);
2240                 DECLARE_MAC_BUF(mac);
2241
2242                 if (sta_id == IWL_INVALID_STATION) {
2243                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
2244                                        print_mac(mac, hdr->addr1));
2245                         sta_id = iwl4965_add_station_flags(priv, hdr->addr1,
2246                                                         0, CMD_ASYNC, NULL);
2247                 }
2248                 if ((sta_id != IWL_INVALID_STATION)) {
2249                         lq_sta->lq.sta_id = sta_id;
2250                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2251                         lq_sta->ibss_sta_added = 1;
2252                         rs_initialize_lq(priv, conf, sta);
2253                 }
2254                 if (!lq_sta->ibss_sta_added)
2255                         goto done;
2256         }
2257
2258 done:
2259         if ((i < 0) || (i > IWL_RATE_COUNT)) {
2260                 sel->rate = rate_lowest(local, sband, sta);
2261                 goto out;
2262         }
2263
2264         sel->rate = &priv->ieee_rates[i];
2265 out:
2266         rcu_read_unlock();
2267 }
2268
2269 static void *rs_alloc_sta(void *priv, gfp_t gfp)
2270 {
2271         struct iwl4965_lq_sta *lq_sta;
2272         int i, j;
2273
2274         IWL_DEBUG_RATE("create station rate scale window\n");
2275
2276         lq_sta = kzalloc(sizeof(struct iwl4965_lq_sta), gfp);
2277
2278         if (lq_sta == NULL)
2279                 return NULL;
2280         lq_sta->lq.sta_id = 0xff;
2281
2282
2283         for (j = 0; j < LQ_SIZE; j++)
2284                 for (i = 0; i < IWL_RATE_COUNT; i++)
2285                         rs_rate_scale_clear_window(&(lq_sta->lq_info[j].win[i]));
2286
2287         return lq_sta;
2288 }
2289
2290 static void rs_rate_init(void *priv_rate, void *priv_sta,
2291                          struct ieee80211_local *local,
2292                          struct sta_info *sta)
2293 {
2294         int i, j;
2295         struct ieee80211_conf *conf = &local->hw.conf;
2296         struct ieee80211_supported_band *sband;
2297         struct iwl4965_priv *priv = (struct iwl4965_priv *)priv_rate;
2298         struct iwl4965_lq_sta *lq_sta = priv_sta;
2299
2300         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
2301
2302         lq_sta->flush_timer = 0;
2303         lq_sta->supp_rates = sta->supp_rates[sband->band];
2304         sta->txrate_idx = 3;
2305         for (j = 0; j < LQ_SIZE; j++)
2306                 for (i = 0; i < IWL_RATE_COUNT; i++)
2307                         rs_rate_scale_clear_window(&(lq_sta->lq_info[j].win[i]));
2308
2309         IWL_DEBUG_RATE("rate scale global init\n");
2310         /* TODO: what is a good starting rate for STA? About middle? Maybe not
2311          * the lowest or the highest rate.. Could consider using RSSI from
2312          * previous packets? Need to have IEEE 802.1X auth succeed immediately
2313          * after assoc.. */
2314
2315         lq_sta->ibss_sta_added = 0;
2316         if (priv->iw_mode == IEEE80211_IF_TYPE_AP) {
2317                 u8 sta_id = iwl4965_hw_find_station(priv, sta->addr);
2318                 DECLARE_MAC_BUF(mac);
2319
2320                 /* for IBSS the call are from tasklet */
2321                 IWL_DEBUG_HT("LQ: ADD station %s\n",
2322                              print_mac(mac, sta->addr));
2323
2324                 if (sta_id == IWL_INVALID_STATION) {
2325                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
2326                                        print_mac(mac, sta->addr));
2327                         sta_id = iwl4965_add_station_flags(priv, sta->addr,
2328                                                         0, CMD_ASYNC, NULL);
2329                 }
2330                 if ((sta_id != IWL_INVALID_STATION)) {
2331                         lq_sta->lq.sta_id = sta_id;
2332                         lq_sta->lq.rs_table[0].rate_n_flags = 0;
2333                 }
2334                 /* FIXME: this is w/a remove it later */
2335                 priv->assoc_station_added = 1;
2336         }
2337
2338         /* Find highest tx rate supported by hardware and destination station */
2339         for (i = 0; i < sband->n_bitrates; i++)
2340                 if (sta->supp_rates[sband->band] & BIT(i))
2341                         sta->txrate_idx = i;
2342
2343         sta->last_txrate_idx = sta->txrate_idx;
2344         /* WTF is with this bogus comment? A doesn't have cck rates */
2345         /* For MODE_IEEE80211A, cck rates are at end of rate table */
2346         if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ)
2347                 sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2348
2349         lq_sta->is_dup = 0;
2350         lq_sta->valid_antenna = priv->valid_antenna;
2351         lq_sta->antenna = priv->antenna;
2352         lq_sta->is_green = rs_use_green(priv, conf);
2353         lq_sta->active_rate = priv->active_rate;
2354         lq_sta->active_rate &= ~(0x1000);
2355         lq_sta->active_rate_basic = priv->active_rate_basic;
2356         lq_sta->band = priv->band;
2357 #ifdef CONFIG_IWL4965_HT
2358         /*
2359          * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2360          * supp_rates[] does not; shift to convert format, force 9 MBits off.
2361          */
2362         lq_sta->active_siso_rate = (priv->current_ht_config.supp_mcs_set[0] << 1);
2363         lq_sta->active_siso_rate |=
2364                         (priv->current_ht_config.supp_mcs_set[0] & 0x1);
2365         lq_sta->active_siso_rate &= ~((u16)0x2);
2366         lq_sta->active_siso_rate =
2367                         lq_sta->active_siso_rate << IWL_FIRST_OFDM_RATE;
2368
2369         /* Same here */
2370         lq_sta->active_mimo_rate = (priv->current_ht_config.supp_mcs_set[1] << 1);
2371         lq_sta->active_mimo_rate |=
2372                         (priv->current_ht_config.supp_mcs_set[1] & 0x1);
2373         lq_sta->active_mimo_rate &= ~((u16)0x2);
2374         lq_sta->active_mimo_rate =
2375                         lq_sta->active_mimo_rate << IWL_FIRST_OFDM_RATE;
2376         IWL_DEBUG_HT("SISO RATE 0x%X MIMO RATE 0x%X\n",
2377                      lq_sta->active_siso_rate,
2378                      lq_sta->active_mimo_rate);
2379         /* as default allow aggregation for all tids */
2380         lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2381 #endif /*CONFIG_IWL4965_HT*/
2382 #ifdef CONFIG_MAC80211_DEBUGFS
2383         lq_sta->drv = priv;
2384 #endif
2385
2386         if (priv->assoc_station_added)
2387                 priv->lq_mngr.lq_ready = 1;
2388
2389         rs_initialize_lq(priv, conf, sta);
2390 }
2391
2392 static void rs_fill_link_cmd(struct iwl4965_lq_sta *lq_sta,
2393                             struct iwl4965_rate *tx_mcs,
2394                             struct iwl4965_link_quality_cmd *lq_cmd)
2395 {
2396         int index = 0;
2397         int rate_idx;
2398         int repeat_rate = 0;
2399         u8 ant_toggle_count = 0;
2400         u8 use_ht_possible = 1;
2401         struct iwl4965_rate new_rate;
2402         struct iwl4965_scale_tbl_info tbl_type = { 0 };
2403
2404         /* Override starting rate (index 0) if needed for debug purposes */
2405         rs_dbgfs_set_mcs(lq_sta, tx_mcs, index);
2406
2407         /* Interpret rate_n_flags */
2408         rs_get_tbl_info_from_mcs(tx_mcs, lq_sta->band,
2409                                   &tbl_type, &rate_idx);
2410
2411         /* How many times should we repeat the initial rate? */
2412         if (is_legacy(tbl_type.lq_type)) {
2413                 ant_toggle_count = 1;
2414                 repeat_rate = IWL_NUMBER_TRY;
2415         } else
2416                 repeat_rate = IWL_HT_NUMBER_TRY;
2417
2418         lq_cmd->general_params.mimo_delimiter =
2419                         is_mimo(tbl_type.lq_type) ? 1 : 0;
2420
2421         /* Fill 1st table entry (index 0) */
2422         lq_cmd->rs_table[index].rate_n_flags =
2423                         cpu_to_le32(tx_mcs->rate_n_flags);
2424         new_rate.rate_n_flags = tx_mcs->rate_n_flags;
2425
2426         if (is_mimo(tbl_type.lq_type) || (tbl_type.antenna_type == ANT_MAIN))
2427                 lq_cmd->general_params.single_stream_ant_msk
2428                         = LINK_QUAL_ANT_A_MSK;
2429         else
2430                 lq_cmd->general_params.single_stream_ant_msk
2431                         = LINK_QUAL_ANT_B_MSK;
2432
2433         index++;
2434         repeat_rate--;
2435
2436         /* Fill rest of rate table */
2437         while (index < LINK_QUAL_MAX_RETRY_NUM) {
2438                 /* Repeat initial/next rate.
2439                  * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2440                  * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2441                 while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2442                         if (is_legacy(tbl_type.lq_type)) {
2443                                 if (ant_toggle_count <
2444                                     NUM_TRY_BEFORE_ANTENNA_TOGGLE)
2445                                         ant_toggle_count++;
2446                                 else {
2447                                         rs_toggle_antenna(&new_rate, &tbl_type);
2448                                         ant_toggle_count = 1;
2449                                 }
2450                         }
2451
2452                         /* Override next rate if needed for debug purposes */
2453                         rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2454
2455                         /* Fill next table entry */
2456                         lq_cmd->rs_table[index].rate_n_flags =
2457                                         cpu_to_le32(new_rate.rate_n_flags);
2458                         repeat_rate--;
2459                         index++;
2460                 }
2461
2462                 rs_get_tbl_info_from_mcs(&new_rate, lq_sta->band, &tbl_type,
2463                                                 &rate_idx);
2464
2465                 /* Indicate to uCode which entries might be MIMO.
2466                  * If initial rate was MIMO, this will finally end up
2467                  * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2468                 if (is_mimo(tbl_type.lq_type))
2469                         lq_cmd->general_params.mimo_delimiter = index;
2470
2471                 /* Get next rate */
2472                 rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2473                                   use_ht_possible, &new_rate);
2474
2475                 /* How many times should we repeat the next rate? */
2476                 if (is_legacy(tbl_type.lq_type)) {
2477                         if (ant_toggle_count < NUM_TRY_BEFORE_ANTENNA_TOGGLE)
2478                                 ant_toggle_count++;
2479                         else {
2480                                 rs_toggle_antenna(&new_rate, &tbl_type);
2481                                 ant_toggle_count = 1;
2482                         }
2483                         repeat_rate = IWL_NUMBER_TRY;
2484                 } else
2485                         repeat_rate = IWL_HT_NUMBER_TRY;
2486
2487                 /* Don't allow HT rates after next pass.
2488                  * rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2489                 use_ht_possible = 0;
2490
2491                 /* Override next rate if needed for debug purposes */
2492                 rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2493
2494                 /* Fill next table entry */
2495                 lq_cmd->rs_table[index].rate_n_flags =
2496                                 cpu_to_le32(new_rate.rate_n_flags);
2497
2498                 index++;
2499                 repeat_rate--;
2500         }
2501
2502         lq_cmd->general_params.dual_stream_ant_msk = 3;
2503         lq_cmd->agg_params.agg_dis_start_th = 3;
2504         lq_cmd->agg_params.agg_time_limit = cpu_to_le16(4000);
2505 }
2506
2507 static void *rs_alloc(struct ieee80211_local *local)
2508 {
2509         return local->hw.priv;
2510 }
2511 /* rate scale requires free function to be implemented */
2512 static void rs_free(void *priv_rate)
2513 {
2514         return;
2515 }
2516
2517 static void rs_clear(void *priv_rate)
2518 {
2519         struct iwl4965_priv *priv = (struct iwl4965_priv *) priv_rate;
2520
2521         IWL_DEBUG_RATE("enter\n");
2522
2523         priv->lq_mngr.lq_ready = 0;
2524
2525         IWL_DEBUG_RATE("leave\n");
2526 }
2527
2528 static void rs_free_sta(void *priv, void *priv_sta)
2529 {
2530         struct iwl4965_lq_sta *lq_sta = priv_sta;
2531
2532         IWL_DEBUG_RATE("enter\n");
2533         kfree(lq_sta);
2534         IWL_DEBUG_RATE("leave\n");
2535 }
2536
2537
2538 #ifdef CONFIG_MAC80211_DEBUGFS
2539 static int open_file_generic(struct inode *inode, struct file *file)
2540 {
2541         file->private_data = inode->i_private;
2542         return 0;
2543 }
2544 static void rs_dbgfs_set_mcs(struct iwl4965_lq_sta *lq_sta,
2545                                 struct iwl4965_rate *mcs, int index)
2546 {
2547         u32 base_rate;
2548
2549         if (lq_sta->band == IEEE80211_BAND_5GHZ)
2550                 base_rate = 0x800D;
2551         else
2552                 base_rate = 0x820A;
2553
2554         if (lq_sta->dbg_fixed.rate_n_flags) {
2555                 if (index < 12)
2556                         mcs->rate_n_flags = lq_sta->dbg_fixed.rate_n_flags;
2557                 else
2558                         mcs->rate_n_flags = base_rate;
2559                 IWL_DEBUG_RATE("Fixed rate ON\n");
2560                 return;
2561         }
2562
2563         IWL_DEBUG_RATE("Fixed rate OFF\n");
2564 }
2565
2566 static ssize_t rs_sta_dbgfs_scale_table_write(struct file *file,
2567                         const char __user *user_buf, size_t count, loff_t *ppos)
2568 {
2569         struct iwl4965_lq_sta *lq_sta = file->private_data;
2570         char buf[64];
2571         int buf_size;
2572         u32 parsed_rate;
2573
2574         memset(buf, 0, sizeof(buf));
2575         buf_size = min(count, sizeof(buf) -  1);
2576         if (copy_from_user(buf, user_buf, buf_size))
2577                 return -EFAULT;
2578
2579         if (sscanf(buf, "%x", &parsed_rate) == 1)
2580                 lq_sta->dbg_fixed.rate_n_flags = parsed_rate;
2581         else
2582                 lq_sta->dbg_fixed.rate_n_flags = 0;
2583
2584         lq_sta->active_rate = 0x0FFF;   /* 1 - 54 MBits, includes CCK */
2585         lq_sta->active_siso_rate = 0x1FD0;      /* 6 - 60 MBits, no 9, no CCK */
2586         lq_sta->active_mimo_rate = 0x1FD0;      /* 6 - 60 MBits, no 9, no CCK */
2587
2588         IWL_DEBUG_RATE("sta_id %d rate 0x%X\n",
2589                 lq_sta->lq.sta_id, lq_sta->dbg_fixed.rate_n_flags);
2590
2591         if (lq_sta->dbg_fixed.rate_n_flags) {
2592                 rs_fill_link_cmd(lq_sta, &lq_sta->dbg_fixed, &lq_sta->lq);
2593                 rs_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC);
2594         }
2595
2596         return count;
2597 }
2598
2599 static ssize_t rs_sta_dbgfs_scale_table_read(struct file *file,
2600                         char __user *user_buf, size_t count, loff_t *ppos)
2601 {
2602         char buff[1024];
2603         int desc = 0;
2604         int i = 0;
2605
2606         struct iwl4965_lq_sta *lq_sta = file->private_data;
2607
2608         desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2609         desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2610                         lq_sta->total_failed, lq_sta->total_success,
2611                         lq_sta->active_rate);
2612         desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2613                         lq_sta->dbg_fixed.rate_n_flags);
2614         desc += sprintf(buff+desc, "general:"
2615                 "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2616                 lq_sta->lq.general_params.flags,
2617                 lq_sta->lq.general_params.mimo_delimiter,
2618                 lq_sta->lq.general_params.single_stream_ant_msk,
2619                 lq_sta->lq.general_params.dual_stream_ant_msk);
2620
2621         desc += sprintf(buff+desc, "agg:"
2622                         "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2623                         le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2624                         lq_sta->lq.agg_params.agg_dis_start_th,
2625                         lq_sta->lq.agg_params.agg_frame_cnt_limit);
2626
2627         desc += sprintf(buff+desc,
2628                         "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2629                         lq_sta->lq.general_params.start_rate_index[0],
2630                         lq_sta->lq.general_params.start_rate_index[1],
2631                         lq_sta->lq.general_params.start_rate_index[2],
2632                         lq_sta->lq.general_params.start_rate_index[3]);
2633
2634
2635         for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++)
2636                 desc += sprintf(buff+desc, " rate[%d] 0x%X\n",
2637                         i, le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2638
2639         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2640 }
2641
2642 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2643         .write = rs_sta_dbgfs_scale_table_write,
2644         .read = rs_sta_dbgfs_scale_table_read,
2645         .open = open_file_generic,
2646 };
2647 static ssize_t rs_sta_dbgfs_stats_table_read(struct file *file,
2648                         char __user *user_buf, size_t count, loff_t *ppos)
2649 {
2650         char buff[1024];
2651         int desc = 0;
2652         int i, j;
2653
2654         struct iwl4965_lq_sta *lq_sta = file->private_data;
2655         for (i = 0; i < LQ_SIZE; i++) {
2656                 desc += sprintf(buff+desc, "%s type=%d SGI=%d FAT=%d DUP=%d\n"
2657                                 "rate=0x%X\n",
2658                                 lq_sta->active_tbl == i?"*":"x",
2659                                 lq_sta->lq_info[i].lq_type,
2660                                 lq_sta->lq_info[i].is_SGI,
2661                                 lq_sta->lq_info[i].is_fat,
2662                                 lq_sta->lq_info[i].is_dup,
2663                                 lq_sta->lq_info[i].current_rate.rate_n_flags);
2664                 for (j = 0; j < IWL_RATE_COUNT; j++) {
2665                         desc += sprintf(buff+desc,
2666                                 "counter=%d success=%d %%=%d\n",
2667                                 lq_sta->lq_info[i].win[j].counter,
2668                                 lq_sta->lq_info[i].win[j].success_counter,
2669                                 lq_sta->lq_info[i].win[j].success_ratio);
2670                 }
2671         }
2672         return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2673 }
2674
2675 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2676         .read = rs_sta_dbgfs_stats_table_read,
2677         .open = open_file_generic,
2678 };
2679
2680 static void rs_add_debugfs(void *priv, void *priv_sta,
2681                                         struct dentry *dir)
2682 {
2683         struct iwl4965_lq_sta *lq_sta = priv_sta;
2684         lq_sta->rs_sta_dbgfs_scale_table_file =
2685                 debugfs_create_file("rate_scale_table", 0600, dir,
2686                                 lq_sta, &rs_sta_dbgfs_scale_table_ops);
2687         lq_sta->rs_sta_dbgfs_stats_table_file =
2688                 debugfs_create_file("rate_stats_table", 0600, dir,
2689                         lq_sta, &rs_sta_dbgfs_stats_table_ops);
2690 #ifdef CONFIG_IWL4965_HT
2691         lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2692                 debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2693                 &lq_sta->tx_agg_tid_en);
2694 #endif
2695
2696 }
2697
2698 static void rs_remove_debugfs(void *priv, void *priv_sta)
2699 {
2700         struct iwl4965_lq_sta *lq_sta = priv_sta;
2701         debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2702         debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2703 #ifdef CONFIG_IWL4965_HT
2704         debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2705 #endif
2706 }
2707 #endif
2708
2709 static struct rate_control_ops rs_ops = {
2710         .module = NULL,
2711         .name = RS_NAME,
2712         .tx_status = rs_tx_status,
2713         .get_rate = rs_get_rate,
2714         .rate_init = rs_rate_init,
2715         .clear = rs_clear,
2716         .alloc = rs_alloc,
2717         .free = rs_free,
2718         .alloc_sta = rs_alloc_sta,
2719         .free_sta = rs_free_sta,
2720 #ifdef CONFIG_MAC80211_DEBUGFS
2721         .add_sta_debugfs = rs_add_debugfs,
2722         .remove_sta_debugfs = rs_remove_debugfs,
2723 #endif
2724 };
2725
2726 int iwl4965_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
2727 {
2728         struct ieee80211_local *local = hw_to_local(hw);
2729         struct iwl4965_priv *priv = hw->priv;
2730         struct iwl4965_lq_sta *lq_sta;
2731         struct sta_info *sta;
2732         int cnt = 0, i;
2733         u32 samples = 0, success = 0, good = 0;
2734         unsigned long now = jiffies;
2735         u32 max_time = 0;
2736         u8 lq_type, antenna;
2737
2738         rcu_read_lock();
2739
2740         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
2741         if (!sta || !sta->rate_ctrl_priv) {
2742                 if (sta)
2743                         IWL_DEBUG_RATE("leave - no private rate data!\n");
2744                 else
2745                         IWL_DEBUG_RATE("leave - no station!\n");
2746                 rcu_read_unlock();
2747                 return sprintf(buf, "station %d not found\n", sta_id);
2748         }
2749
2750         lq_sta = (void *)sta->rate_ctrl_priv;
2751
2752         lq_type = lq_sta->lq_info[lq_sta->active_tbl].lq_type;
2753         antenna = lq_sta->lq_info[lq_sta->active_tbl].antenna_type;
2754
2755         if (is_legacy(lq_type))
2756                 i = IWL_RATE_54M_INDEX;
2757         else
2758                 i = IWL_RATE_60M_INDEX;
2759         while (1) {
2760                 u64 mask;
2761                 int j;
2762                 int active = lq_sta->active_tbl;
2763
2764                 cnt +=
2765                     sprintf(&buf[cnt], " %2dMbs: ", iwl4965_rates[i].ieee / 2);
2766
2767                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
2768                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
2769                         buf[cnt++] =
2770                                 (lq_sta->lq_info[active].win[i].data & mask)
2771                                 ? '1' : '0';
2772
2773                 samples += lq_sta->lq_info[active].win[i].counter;
2774                 good += lq_sta->lq_info[active].win[i].success_counter;
2775                 success += lq_sta->lq_info[active].win[i].success_counter *
2776                            iwl4965_rates[i].ieee;
2777
2778                 if (lq_sta->lq_info[active].win[i].stamp) {
2779                         int delta =
2780                                    jiffies_to_msecs(now -
2781                                    lq_sta->lq_info[active].win[i].stamp);
2782
2783                         if (delta > max_time)
2784                                 max_time = delta;
2785
2786                         cnt += sprintf(&buf[cnt], "%5dms\n", delta);
2787                 } else
2788                         buf[cnt++] = '\n';
2789
2790                 j = iwl4965_get_prev_ieee_rate(i);
2791                 if (j == i)
2792                         break;
2793                 i = j;
2794         }
2795
2796         /* Display the average rate of all samples taken.
2797          *
2798          * NOTE:  We multiply # of samples by 2 since the IEEE measurement
2799          * added from iwl4965_rates is actually 2X the rate */
2800         if (samples)
2801                 cnt += sprintf(&buf[cnt],
2802                          "\nAverage rate is %3d.%02dMbs over last %4dms\n"
2803                          "%3d%% success (%d good packets over %d tries)\n",
2804                          success / (2 * samples), (success * 5 / samples) % 10,
2805                          max_time, good * 100 / samples, good, samples);
2806         else
2807                 cnt += sprintf(&buf[cnt], "\nAverage rate: 0Mbs\n");
2808
2809         cnt += sprintf(&buf[cnt], "\nrate scale type %d antenna %d "
2810                          "active_search %d rate index %d\n", lq_type, antenna,
2811                          lq_sta->search_better_tbl, sta->last_txrate_idx);
2812
2813         rcu_read_unlock();
2814         return cnt;
2815 }
2816
2817 void iwl4965_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
2818 {
2819         struct iwl4965_priv *priv = hw->priv;
2820
2821         priv->lq_mngr.lq_ready = 1;
2822 }
2823
2824 void iwl4965_rate_control_register(struct ieee80211_hw *hw)
2825 {
2826         ieee80211_rate_control_register(&rs_ops);
2827 }
2828
2829 void iwl4965_rate_control_unregister(struct ieee80211_hw *hw)
2830 {
2831         ieee80211_rate_control_unregister(&rs_ops);
2832 }
2833