Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-2.6] / drivers / net / wireless / iwlwifi / iwl-3945-rs.c
1 /******************************************************************************
2  *
3  * Copyright(c) 2005 - 2008 Intel Corporation. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
17  *
18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  * Contact Information:
22  * James P. Ketrenos <ipw2100-admin@linux.intel.com>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  *****************************************************************************/
26
27 #include <linux/kernel.h>
28 #include <linux/init.h>
29 #include <linux/skbuff.h>
30 #include <linux/wireless.h>
31 #include <net/mac80211.h>
32 #include <net/ieee80211.h>
33
34 #include <linux/netdevice.h>
35 #include <linux/etherdevice.h>
36 #include <linux/delay.h>
37
38 #include <linux/workqueue.h>
39
40 #include "../net/mac80211/rate.h"
41
42 #include "iwl-3945.h"
43
44 #define RS_NAME "iwl-3945-rs"
45
46 struct iwl3945_rate_scale_data {
47         u64 data;
48         s32 success_counter;
49         s32 success_ratio;
50         s32 counter;
51         s32 average_tpt;
52         unsigned long stamp;
53 };
54
55 struct iwl3945_rs_sta {
56         spinlock_t lock;
57         s32 *expected_tpt;
58         unsigned long last_partial_flush;
59         unsigned long last_flush;
60         u32 flush_time;
61         u32 last_tx_packets;
62         u32 tx_packets;
63         u8 tgg;
64         u8 flush_pending;
65         u8 start_rate;
66         u8 ibss_sta_added;
67         struct timer_list rate_scale_flush;
68         struct iwl3945_rate_scale_data win[IWL_RATE_COUNT];
69 };
70
71 static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT] = {
72         7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
73 };
74
75 static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT] = {
76         7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
77 };
78
79 static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT] = {
80         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
81 };
82
83 static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT] = {
84         7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
85 };
86
87 struct iwl3945_tpt_entry {
88         s8 min_rssi;
89         u8 index;
90 };
91
92 static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
93         {-60, IWL_RATE_54M_INDEX},
94         {-64, IWL_RATE_48M_INDEX},
95         {-72, IWL_RATE_36M_INDEX},
96         {-80, IWL_RATE_24M_INDEX},
97         {-84, IWL_RATE_18M_INDEX},
98         {-85, IWL_RATE_12M_INDEX},
99         {-87, IWL_RATE_9M_INDEX},
100         {-89, IWL_RATE_6M_INDEX}
101 };
102
103 static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
104         {-60, IWL_RATE_54M_INDEX},
105         {-64, IWL_RATE_48M_INDEX},
106         {-68, IWL_RATE_36M_INDEX},
107         {-80, IWL_RATE_24M_INDEX},
108         {-84, IWL_RATE_18M_INDEX},
109         {-85, IWL_RATE_12M_INDEX},
110         {-86, IWL_RATE_11M_INDEX},
111         {-88, IWL_RATE_5M_INDEX},
112         {-90, IWL_RATE_2M_INDEX},
113         {-92, IWL_RATE_1M_INDEX}
114 };
115
116 #define IWL_RATE_MAX_WINDOW          62
117 #define IWL_RATE_FLUSH        (3*HZ/10)
118 #define IWL_RATE_WIN_FLUSH       (HZ/2)
119 #define IWL_RATE_HIGH_TH          11520
120 #define IWL_RATE_MIN_FAILURE_TH       8
121 #define IWL_RATE_MIN_SUCCESS_TH       8
122 #define IWL_RATE_DECREASE_TH       1920
123
124 static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, enum ieee80211_band band)
125 {
126         u32 index = 0;
127         u32 table_size = 0;
128         struct iwl3945_tpt_entry *tpt_table = NULL;
129
130         if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
131                 rssi = IWL_MIN_RSSI_VAL;
132
133         switch (band) {
134         case IEEE80211_BAND_2GHZ:
135                 tpt_table = iwl3945_tpt_table_g;
136                 table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
137                 break;
138
139         case IEEE80211_BAND_5GHZ:
140                 tpt_table = iwl3945_tpt_table_a;
141                 table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
142                 break;
143
144         default:
145                 BUG();
146                 break;
147         }
148
149         while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
150                 index++;
151
152         index = min(index, (table_size - 1));
153
154         return tpt_table[index].index;
155 }
156
157 static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
158 {
159         window->data = 0;
160         window->success_counter = 0;
161         window->success_ratio = -1;
162         window->counter = 0;
163         window->average_tpt = IWL_INV_TPT;
164         window->stamp = 0;
165 }
166
167 /**
168  * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
169  *
170  * Returns the number of windows that have gathered data but were
171  * not flushed.  If there were any that were not flushed, then
172  * reschedule the rate flushing routine.
173  */
174 static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
175 {
176         int unflushed = 0;
177         int i;
178         unsigned long flags;
179
180         /*
181          * For each rate, if we have collected data on that rate
182          * and it has been more than IWL_RATE_WIN_FLUSH
183          * since we flushed, clear out the gathered statistics
184          */
185         for (i = 0; i < IWL_RATE_COUNT; i++) {
186                 if (!rs_sta->win[i].counter)
187                         continue;
188
189                 spin_lock_irqsave(&rs_sta->lock, flags);
190                 if (time_after(jiffies, rs_sta->win[i].stamp +
191                                IWL_RATE_WIN_FLUSH)) {
192                         IWL_DEBUG_RATE("flushing %d samples of rate "
193                                        "index %d\n",
194                                        rs_sta->win[i].counter, i);
195                         iwl3945_clear_window(&rs_sta->win[i]);
196                 } else
197                         unflushed++;
198                 spin_unlock_irqrestore(&rs_sta->lock, flags);
199         }
200
201         return unflushed;
202 }
203
204 #define IWL_RATE_FLUSH_MAX              5000    /* msec */
205 #define IWL_RATE_FLUSH_MIN              50      /* msec */
206
207 static void iwl3945_bg_rate_scale_flush(unsigned long data)
208 {
209         struct iwl3945_rs_sta *rs_sta = (void *)data;
210         int unflushed = 0;
211         unsigned long flags;
212         u32 packet_count, duration, pps;
213
214         IWL_DEBUG_RATE("enter\n");
215
216         unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
217
218         spin_lock_irqsave(&rs_sta->lock, flags);
219
220         rs_sta->flush_pending = 0;
221
222         /* Number of packets Rx'd since last time this timer ran */
223         packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
224
225         rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
226
227         if (unflushed) {
228                 duration =
229                     jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
230 /*              duration = jiffies_to_msecs(rs_sta->flush_time); */
231
232                 IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
233                                packet_count, duration);
234
235                 /* Determine packets per second */
236                 if (duration)
237                         pps = (packet_count * 1000) / duration;
238                 else
239                         pps = 0;
240
241                 if (pps) {
242                         duration = IWL_RATE_FLUSH_MAX / pps;
243                         if (duration < IWL_RATE_FLUSH_MIN)
244                                 duration = IWL_RATE_FLUSH_MIN;
245                 } else
246                         duration = IWL_RATE_FLUSH_MAX;
247
248                 rs_sta->flush_time = msecs_to_jiffies(duration);
249
250                 IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
251                                duration, packet_count);
252
253                 mod_timer(&rs_sta->rate_scale_flush, jiffies +
254                           rs_sta->flush_time);
255
256                 rs_sta->last_partial_flush = jiffies;
257         }
258
259         /* If there weren't any unflushed entries, we don't schedule the timer
260          * to run again */
261
262         rs_sta->last_flush = jiffies;
263
264         spin_unlock_irqrestore(&rs_sta->lock, flags);
265
266         IWL_DEBUG_RATE("leave\n");
267 }
268
269 /**
270  * iwl3945_collect_tx_data - Update the success/failure sliding window
271  *
272  * We keep a sliding window of the last 64 packets transmitted
273  * at this rate.  window->data contains the bitmask of successful
274  * packets.
275  */
276 static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
277                                 struct iwl3945_rate_scale_data *window,
278                                 int success, int retries)
279 {
280         unsigned long flags;
281
282         if (!retries) {
283                 IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
284                 return;
285         }
286
287         while (retries--) {
288                 spin_lock_irqsave(&rs_sta->lock, flags);
289
290                 /* If we have filled up the window then subtract one from the
291                  * success counter if the high-bit is counting toward
292                  * success */
293                 if (window->counter == IWL_RATE_MAX_WINDOW) {
294                         if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
295                                 window->success_counter--;
296                 } else
297                         window->counter++;
298
299                 /* Slide the window to the left one bit */
300                 window->data = (window->data << 1);
301
302                 /* If this packet was a success then set the low bit high */
303                 if (success) {
304                         window->success_counter++;
305                         window->data |= 1;
306                 }
307
308                 /* window->counter can't be 0 -- it is either >0 or
309                  * IWL_RATE_MAX_WINDOW */
310                 window->success_ratio = 12800 * window->success_counter /
311                     window->counter;
312
313                 /* Tag this window as having been updated */
314                 window->stamp = jiffies;
315
316                 spin_unlock_irqrestore(&rs_sta->lock, flags);
317         }
318 }
319
320 static void rs_rate_init(void *priv_rate, void *priv_sta,
321                          struct ieee80211_local *local, struct sta_info *sta)
322 {
323         int i;
324
325         IWL_DEBUG_RATE("enter\n");
326
327         /* TODO: what is a good starting rate for STA? About middle? Maybe not
328          * the lowest or the highest rate.. Could consider using RSSI from
329          * previous packets? Need to have IEEE 802.1X auth succeed immediately
330          * after assoc.. */
331
332         for (i = IWL_RATE_COUNT - 1; i >= 0; i--) {
333                 if (sta->supp_rates[local->hw.conf.channel->band] & (1 << i)) {
334                         sta->txrate_idx = i;
335                         break;
336                 }
337         }
338
339         sta->last_txrate_idx = sta->txrate_idx;
340
341         /* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
342         if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ)
343                 sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
344
345         IWL_DEBUG_RATE("leave\n");
346 }
347
348 static void *rs_alloc(struct ieee80211_local *local)
349 {
350         return local->hw.priv;
351 }
352
353 /* rate scale requires free function to be implemented */
354 static void rs_free(void *priv)
355 {
356         return;
357 }
358 static void rs_clear(void *priv)
359 {
360         return;
361 }
362
363
364 static void *rs_alloc_sta(void *priv, gfp_t gfp)
365 {
366         struct iwl3945_rs_sta *rs_sta;
367         int i;
368
369         IWL_DEBUG_RATE("enter\n");
370
371         rs_sta = kzalloc(sizeof(struct iwl3945_rs_sta), gfp);
372         if (!rs_sta) {
373                 IWL_DEBUG_RATE("leave: ENOMEM\n");
374                 return NULL;
375         }
376
377         spin_lock_init(&rs_sta->lock);
378
379         rs_sta->start_rate = IWL_RATE_INVALID;
380
381         /* default to just 802.11b */
382         rs_sta->expected_tpt = iwl3945_expected_tpt_b;
383
384         rs_sta->last_partial_flush = jiffies;
385         rs_sta->last_flush = jiffies;
386         rs_sta->flush_time = IWL_RATE_FLUSH;
387         rs_sta->last_tx_packets = 0;
388         rs_sta->ibss_sta_added = 0;
389
390         init_timer(&rs_sta->rate_scale_flush);
391         rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
392         rs_sta->rate_scale_flush.function = &iwl3945_bg_rate_scale_flush;
393
394         for (i = 0; i < IWL_RATE_COUNT; i++)
395                 iwl3945_clear_window(&rs_sta->win[i]);
396
397         IWL_DEBUG_RATE("leave\n");
398
399         return rs_sta;
400 }
401
402 static void rs_free_sta(void *priv, void *priv_sta)
403 {
404         struct iwl3945_rs_sta *rs_sta = priv_sta;
405
406         IWL_DEBUG_RATE("enter\n");
407         del_timer_sync(&rs_sta->rate_scale_flush);
408         kfree(rs_sta);
409         IWL_DEBUG_RATE("leave\n");
410 }
411
412
413 /*
414  * get ieee prev rate from rate scale table.
415  * for A and B mode we need to overright prev
416  * value
417  */
418 static int rs_adjust_next_rate(struct iwl3945_priv *priv, int rate)
419 {
420         int next_rate = iwl3945_get_prev_ieee_rate(rate);
421
422         switch (priv->band) {
423         case IEEE80211_BAND_5GHZ:
424                 if (rate == IWL_RATE_12M_INDEX)
425                         next_rate = IWL_RATE_9M_INDEX;
426                 else if (rate == IWL_RATE_6M_INDEX)
427                         next_rate = IWL_RATE_6M_INDEX;
428                 break;
429 /* XXX cannot be invoked in current mac80211 so not a regression
430         case MODE_IEEE80211B:
431                 if (rate == IWL_RATE_11M_INDEX_TABLE)
432                         next_rate = IWL_RATE_5M_INDEX_TABLE;
433                 break;
434  */
435         default:
436                 break;
437         }
438
439         return next_rate;
440 }
441 /**
442  * rs_tx_status - Update rate control values based on Tx results
443  *
444  * NOTE: Uses iwl3945_priv->retry_rate for the # of retries attempted by
445  * the hardware for each rate.
446  */
447 static void rs_tx_status(void *priv_rate,
448                          struct net_device *dev,
449                          struct sk_buff *skb,
450                          struct ieee80211_tx_status *tx_resp)
451 {
452         u8 retries, current_count;
453         int scale_rate_index, first_index, last_index;
454         unsigned long flags;
455         struct sta_info *sta;
456         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
457         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
458         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
459         struct iwl3945_rs_sta *rs_sta;
460         struct ieee80211_supported_band *sband;
461
462         IWL_DEBUG_RATE("enter\n");
463
464         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
465
466
467         retries = tx_resp->retry_count;
468         first_index = tx_resp->control.tx_rate->hw_value;
469         if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
470                 IWL_DEBUG_RATE("leave: Rate out of bounds: %d\n", first_index);
471                 return;
472         }
473
474         rcu_read_lock();
475
476         sta = sta_info_get(local, hdr->addr1);
477         if (!sta || !sta->rate_ctrl_priv) {
478                 rcu_read_unlock();
479                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
480                 return;
481         }
482
483         rs_sta = (void *)sta->rate_ctrl_priv;
484
485         rs_sta->tx_packets++;
486
487         scale_rate_index = first_index;
488         last_index = first_index;
489
490         /*
491          * Update the window for each rate.  We determine which rates
492          * were Tx'd based on the total number of retries vs. the number
493          * of retries configured for each rate -- currently set to the
494          * priv value 'retry_rate' vs. rate specific
495          *
496          * On exit from this while loop last_index indicates the rate
497          * at which the frame was finally transmitted (or failed if no
498          * ACK)
499          */
500         while (retries > 0) {
501                 if (retries < priv->retry_rate) {
502                         current_count = retries;
503                         last_index = scale_rate_index;
504                 } else {
505                         current_count = priv->retry_rate;
506                         last_index = rs_adjust_next_rate(priv,
507                                                          scale_rate_index);
508                 }
509
510                 /* Update this rate accounting for as many retries
511                  * as was used for it (per current_count) */
512                 iwl3945_collect_tx_data(rs_sta,
513                                     &rs_sta->win[scale_rate_index],
514                                     0, current_count);
515                 IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
516                                scale_rate_index, current_count);
517
518                 retries -= current_count;
519
520                 if (retries)
521                         scale_rate_index =
522                             rs_adjust_next_rate(priv, scale_rate_index);
523         }
524
525
526         /* Update the last index window with success/failure based on ACK */
527         IWL_DEBUG_RATE("Update rate %d with %s.\n",
528                        last_index,
529                        (tx_resp->flags & IEEE80211_TX_STATUS_ACK) ?
530                        "success" : "failure");
531         iwl3945_collect_tx_data(rs_sta,
532                             &rs_sta->win[last_index],
533                             tx_resp->flags & IEEE80211_TX_STATUS_ACK, 1);
534
535         /* We updated the rate scale window -- if its been more than
536          * flush_time since the last run, schedule the flush
537          * again */
538         spin_lock_irqsave(&rs_sta->lock, flags);
539
540         if (!rs_sta->flush_pending &&
541             time_after(jiffies, rs_sta->last_partial_flush +
542                        rs_sta->flush_time)) {
543
544                 rs_sta->flush_pending = 1;
545                 mod_timer(&rs_sta->rate_scale_flush,
546                           jiffies + rs_sta->flush_time);
547         }
548
549         spin_unlock_irqrestore(&rs_sta->lock, flags);
550
551         rcu_read_unlock();
552
553         IWL_DEBUG_RATE("leave\n");
554
555         return;
556 }
557
558 static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
559                                  u8 index, u16 rate_mask, enum ieee80211_band band)
560 {
561         u8 high = IWL_RATE_INVALID;
562         u8 low = IWL_RATE_INVALID;
563
564         /* 802.11A walks to the next literal adjacent rate in
565          * the rate table */
566         if (unlikely(band == IEEE80211_BAND_5GHZ)) {
567                 int i;
568                 u32 mask;
569
570                 /* Find the previous rate that is in the rate mask */
571                 i = index - 1;
572                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
573                         if (rate_mask & mask) {
574                                 low = i;
575                                 break;
576                         }
577                 }
578
579                 /* Find the next rate that is in the rate mask */
580                 i = index + 1;
581                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
582                         if (rate_mask & mask) {
583                                 high = i;
584                                 break;
585                         }
586                 }
587
588                 return (high << 8) | low;
589         }
590
591         low = index;
592         while (low != IWL_RATE_INVALID) {
593                 if (rs_sta->tgg)
594                         low = iwl3945_rates[low].prev_rs_tgg;
595                 else
596                         low = iwl3945_rates[low].prev_rs;
597                 if (low == IWL_RATE_INVALID)
598                         break;
599                 if (rate_mask & (1 << low))
600                         break;
601                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
602         }
603
604         high = index;
605         while (high != IWL_RATE_INVALID) {
606                 if (rs_sta->tgg)
607                         high = iwl3945_rates[high].next_rs_tgg;
608                 else
609                         high = iwl3945_rates[high].next_rs;
610                 if (high == IWL_RATE_INVALID)
611                         break;
612                 if (rate_mask & (1 << high))
613                         break;
614                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
615         }
616
617         return (high << 8) | low;
618 }
619
620 /**
621  * rs_get_rate - find the rate for the requested packet
622  *
623  * Returns the ieee80211_rate structure allocated by the driver.
624  *
625  * The rate control algorithm has no internal mapping between hw_mode's
626  * rate ordering and the rate ordering used by the rate control algorithm.
627  *
628  * The rate control algorithm uses a single table of rates that goes across
629  * the entire A/B/G spectrum vs. being limited to just one particular
630  * hw_mode.
631  *
632  * As such, we can't convert the index obtained below into the hw_mode's
633  * rate table and must reference the driver allocated rate table
634  *
635  */
636 static void rs_get_rate(void *priv_rate, struct net_device *dev,
637                         struct ieee80211_supported_band *sband,
638                         struct sk_buff *skb,
639                         struct rate_selection *sel)
640 {
641         u8 low = IWL_RATE_INVALID;
642         u8 high = IWL_RATE_INVALID;
643         u16 high_low;
644         int index;
645         struct iwl3945_rs_sta *rs_sta;
646         struct iwl3945_rate_scale_data *window = NULL;
647         int current_tpt = IWL_INV_TPT;
648         int low_tpt = IWL_INV_TPT;
649         int high_tpt = IWL_INV_TPT;
650         u32 fail_count;
651         s8 scale_action = 0;
652         unsigned long flags;
653         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
654         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
655         struct sta_info *sta;
656         u16 fc, rate_mask;
657         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
658         DECLARE_MAC_BUF(mac);
659
660         IWL_DEBUG_RATE("enter\n");
661
662         rcu_read_lock();
663
664         sta = sta_info_get(local, hdr->addr1);
665
666         /* Send management frames and broadcast/multicast data using lowest
667          * rate. */
668         fc = le16_to_cpu(hdr->frame_control);
669         if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
670             is_multicast_ether_addr(hdr->addr1) ||
671             !sta || !sta->rate_ctrl_priv) {
672                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
673                 sel->rate = rate_lowest(local, sband, sta);
674                 rcu_read_unlock();
675                 return;
676         }
677
678         rate_mask = sta->supp_rates[sband->band];
679         index = min(sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT - 1);
680
681         if (sband->band == IEEE80211_BAND_5GHZ)
682                 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
683
684         rs_sta = (void *)sta->rate_ctrl_priv;
685
686         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
687             !rs_sta->ibss_sta_added) {
688                 u8 sta_id = iwl3945_hw_find_station(priv, hdr->addr1);
689
690                 if (sta_id == IWL_INVALID_STATION) {
691                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
692                                        print_mac(mac, hdr->addr1));
693                         sta_id = iwl3945_add_station(priv,
694                                     hdr->addr1, 0, CMD_ASYNC);
695                 }
696                 if (sta_id != IWL_INVALID_STATION)
697                         rs_sta->ibss_sta_added = 1;
698         }
699
700         spin_lock_irqsave(&rs_sta->lock, flags);
701
702         if (rs_sta->start_rate != IWL_RATE_INVALID) {
703                 index = rs_sta->start_rate;
704                 rs_sta->start_rate = IWL_RATE_INVALID;
705         }
706
707         window = &(rs_sta->win[index]);
708
709         fail_count = window->counter - window->success_counter;
710
711         if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
712              (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
713                 window->average_tpt = IWL_INV_TPT;
714                 spin_unlock_irqrestore(&rs_sta->lock, flags);
715
716                 IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
717                                "counter: %d, success_counter: %d, "
718                                "expected_tpt is %sNULL\n",
719                                index,
720                                window->counter,
721                                window->success_counter,
722                                rs_sta->expected_tpt ? "not " : "");
723                 goto out;
724
725         }
726
727         window->average_tpt = ((window->success_ratio *
728                                 rs_sta->expected_tpt[index] + 64) / 128);
729         current_tpt = window->average_tpt;
730
731         high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
732                                              sband->band);
733         low = high_low & 0xff;
734         high = (high_low >> 8) & 0xff;
735
736         if (low != IWL_RATE_INVALID)
737                 low_tpt = rs_sta->win[low].average_tpt;
738
739         if (high != IWL_RATE_INVALID)
740                 high_tpt = rs_sta->win[high].average_tpt;
741
742         spin_unlock_irqrestore(&rs_sta->lock, flags);
743
744         scale_action = 1;
745
746         if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
747                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
748                 scale_action = -1;
749         } else if ((low_tpt == IWL_INV_TPT) && (high_tpt == IWL_INV_TPT))
750                 scale_action = 1;
751         else if ((low_tpt != IWL_INV_TPT) && (high_tpt != IWL_INV_TPT) &&
752                  (low_tpt < current_tpt) && (high_tpt < current_tpt)) {
753                 IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
754                                "current_tpt [%d]\n",
755                                low_tpt, high_tpt, current_tpt);
756                 scale_action = 0;
757         } else {
758                 if (high_tpt != IWL_INV_TPT) {
759                         if (high_tpt > current_tpt)
760                                 scale_action = 1;
761                         else {
762                                 IWL_DEBUG_RATE
763                                     ("decrease rate because of high tpt\n");
764                                 scale_action = -1;
765                         }
766                 } else if (low_tpt != IWL_INV_TPT) {
767                         if (low_tpt > current_tpt) {
768                                 IWL_DEBUG_RATE
769                                     ("decrease rate because of low tpt\n");
770                                 scale_action = -1;
771                         } else
772                                 scale_action = 1;
773                 }
774         }
775
776         if ((window->success_ratio > IWL_RATE_HIGH_TH) ||
777             (current_tpt > window->average_tpt)) {
778                 IWL_DEBUG_RATE("No action -- success_ratio [%d] > HIGH_TH or "
779                                "current_tpt [%d] > average_tpt [%d]\n",
780                                window->success_ratio,
781                                current_tpt, window->average_tpt);
782                 scale_action = 0;
783         }
784
785         switch (scale_action) {
786         case -1:
787                 if (low != IWL_RATE_INVALID)
788                         index = low;
789                 break;
790
791         case 1:
792                 if (high != IWL_RATE_INVALID)
793                         index = high;
794
795                 break;
796
797         case 0:
798         default:
799                 break;
800         }
801
802         IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
803                        index, scale_action, low, high);
804
805  out:
806
807         sta->last_txrate_idx = index;
808         if (sband->band == IEEE80211_BAND_5GHZ)
809                 sta->txrate_idx = sta->last_txrate_idx - IWL_FIRST_OFDM_RATE;
810         else
811                 sta->txrate_idx = sta->last_txrate_idx;
812
813         rcu_read_unlock();
814
815         IWL_DEBUG_RATE("leave: %d\n", index);
816
817         sel->rate = &sband->bitrates[sta->txrate_idx];
818 }
819
820 static struct rate_control_ops rs_ops = {
821         .module = NULL,
822         .name = RS_NAME,
823         .tx_status = rs_tx_status,
824         .get_rate = rs_get_rate,
825         .rate_init = rs_rate_init,
826         .clear = rs_clear,
827         .alloc = rs_alloc,
828         .free = rs_free,
829         .alloc_sta = rs_alloc_sta,
830         .free_sta = rs_free_sta,
831 };
832
833 int iwl3945_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
834 {
835         struct ieee80211_local *local = hw_to_local(hw);
836         struct iwl3945_priv *priv = hw->priv;
837         struct iwl3945_rs_sta *rs_sta;
838         struct sta_info *sta;
839         unsigned long flags;
840         int count = 0, i;
841         u32 samples = 0, success = 0, good = 0;
842         unsigned long now = jiffies;
843         u32 max_time = 0;
844
845         rcu_read_lock();
846
847         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
848         if (!sta || !sta->rate_ctrl_priv) {
849                 if (sta)
850                         IWL_DEBUG_RATE("leave - no private rate data!\n");
851                 else
852                         IWL_DEBUG_RATE("leave - no station!\n");
853                 rcu_read_unlock();
854                 return sprintf(buf, "station %d not found\n", sta_id);
855         }
856
857         rs_sta = (void *)sta->rate_ctrl_priv;
858         spin_lock_irqsave(&rs_sta->lock, flags);
859         i = IWL_RATE_54M_INDEX;
860         while (1) {
861                 u64 mask;
862                 int j;
863
864                 count +=
865                     sprintf(&buf[count], " %2dMbs: ", iwl3945_rates[i].ieee / 2);
866
867                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
868                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
869                         buf[count++] =
870                             (rs_sta->win[i].data & mask) ? '1' : '0';
871
872                 samples += rs_sta->win[i].counter;
873                 good += rs_sta->win[i].success_counter;
874                 success += rs_sta->win[i].success_counter *
875                                                 iwl3945_rates[i].ieee;
876
877                 if (rs_sta->win[i].stamp) {
878                         int delta =
879                             jiffies_to_msecs(now - rs_sta->win[i].stamp);
880
881                         if (delta > max_time)
882                                 max_time = delta;
883
884                         count += sprintf(&buf[count], "%5dms\n", delta);
885                 } else
886                         buf[count++] = '\n';
887
888                 j = iwl3945_get_prev_ieee_rate(i);
889                 if (j == i)
890                         break;
891                 i = j;
892         }
893         spin_unlock_irqrestore(&rs_sta->lock, flags);
894         rcu_read_unlock();
895
896         /* Display the average rate of all samples taken.
897          *
898          * NOTE:  We multiple # of samples by 2 since the IEEE measurement
899          * added from iwl3945_rates is actually 2X the rate */
900         if (samples)
901                 count += sprintf(
902                         &buf[count],
903                         "\nAverage rate is %3d.%02dMbs over last %4dms\n"
904                         "%3d%% success (%d good packets over %d tries)\n",
905                         success / (2 * samples), (success * 5 / samples) % 10,
906                         max_time, good * 100 / samples, good, samples);
907         else
908                 count += sprintf(&buf[count], "\nAverage rate: 0Mbs\n");
909
910         return count;
911 }
912
913 void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
914 {
915         struct iwl3945_priv *priv = hw->priv;
916         s32 rssi = 0;
917         unsigned long flags;
918         struct ieee80211_local *local = hw_to_local(hw);
919         struct iwl3945_rs_sta *rs_sta;
920         struct sta_info *sta;
921
922         IWL_DEBUG_RATE("enter\n");
923
924         if (!local->rate_ctrl->ops->name ||
925             strcmp(local->rate_ctrl->ops->name, RS_NAME)) {
926                 IWL_WARNING("iwl-3945-rs not selected as rate control algo!\n");
927                 IWL_DEBUG_RATE("leave - mac80211 picked the wrong RC algo.\n");
928                 return;
929         }
930
931         rcu_read_lock();
932
933         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
934         if (!sta || !sta->rate_ctrl_priv) {
935                 IWL_DEBUG_RATE("leave - no private rate data!\n");
936                 rcu_read_unlock();
937                 return;
938         }
939
940         rs_sta = (void *)sta->rate_ctrl_priv;
941
942         spin_lock_irqsave(&rs_sta->lock, flags);
943
944         rs_sta->tgg = 0;
945         switch (priv->band) {
946         case IEEE80211_BAND_2GHZ:
947                 /* TODO: this always does G, not a regression */
948                 if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
949                         rs_sta->tgg = 1;
950                         rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
951                 } else
952                         rs_sta->expected_tpt = iwl3945_expected_tpt_g;
953                 break;
954
955         case IEEE80211_BAND_5GHZ:
956                 rs_sta->expected_tpt = iwl3945_expected_tpt_a;
957                 break;
958         case IEEE80211_NUM_BANDS:
959                 BUG();
960                 break;
961         }
962
963         rcu_read_unlock();
964         spin_unlock_irqrestore(&rs_sta->lock, flags);
965
966         rssi = priv->last_rx_rssi;
967         if (rssi == 0)
968                 rssi = IWL_MIN_RSSI_VAL;
969
970         IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
971
972         rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
973
974         IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
975                        "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
976                        iwl3945_rates[rs_sta->start_rate].plcp);
977 }
978
979 int iwl3945_rate_control_register(void)
980 {
981         return ieee80211_rate_control_register(&rs_ops);
982 }
983
984 void iwl3945_rate_control_unregister(void)
985 {
986         ieee80211_rate_control_unregister(&rs_ops);
987 }
988
989