mac80211: move TX info into skb->cb
[linux-2.6.git] / 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
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/rate.h"
40
41 #include "iwl-3945.h"
42
43 #define RS_NAME "iwl-3945-rs"
44
45 struct iwl3945_rate_scale_data {
46         u64 data;
47         s32 success_counter;
48         s32 success_ratio;
49         s32 counter;
50         s32 average_tpt;
51         unsigned long stamp;
52 };
53
54 struct iwl3945_rs_sta {
55         spinlock_t lock;
56         s32 *expected_tpt;
57         unsigned long last_partial_flush;
58         unsigned long last_flush;
59         u32 flush_time;
60         u32 last_tx_packets;
61         u32 tx_packets;
62         u8 tgg;
63         u8 flush_pending;
64         u8 start_rate;
65         u8 ibss_sta_added;
66         struct timer_list rate_scale_flush;
67         struct iwl3945_rate_scale_data win[IWL_RATE_COUNT];
68 };
69
70 static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT] = {
71         7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
72 };
73
74 static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT] = {
75         7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
76 };
77
78 static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT] = {
79         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
80 };
81
82 static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT] = {
83         7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
84 };
85
86 struct iwl3945_tpt_entry {
87         s8 min_rssi;
88         u8 index;
89 };
90
91 static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
92         {-60, IWL_RATE_54M_INDEX},
93         {-64, IWL_RATE_48M_INDEX},
94         {-72, IWL_RATE_36M_INDEX},
95         {-80, IWL_RATE_24M_INDEX},
96         {-84, IWL_RATE_18M_INDEX},
97         {-85, IWL_RATE_12M_INDEX},
98         {-87, IWL_RATE_9M_INDEX},
99         {-89, IWL_RATE_6M_INDEX}
100 };
101
102 static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
103         {-60, IWL_RATE_54M_INDEX},
104         {-64, IWL_RATE_48M_INDEX},
105         {-68, IWL_RATE_36M_INDEX},
106         {-80, IWL_RATE_24M_INDEX},
107         {-84, IWL_RATE_18M_INDEX},
108         {-85, IWL_RATE_12M_INDEX},
109         {-86, IWL_RATE_11M_INDEX},
110         {-88, IWL_RATE_5M_INDEX},
111         {-90, IWL_RATE_2M_INDEX},
112         {-92, IWL_RATE_1M_INDEX}
113 };
114
115 #define IWL_RATE_MAX_WINDOW          62
116 #define IWL_RATE_FLUSH        (3*HZ/10)
117 #define IWL_RATE_WIN_FLUSH       (HZ/2)
118 #define IWL_RATE_HIGH_TH          11520
119 #define IWL_RATE_MIN_FAILURE_TH       8
120 #define IWL_RATE_MIN_SUCCESS_TH       8
121 #define IWL_RATE_DECREASE_TH       1920
122
123 static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, enum ieee80211_band band)
124 {
125         u32 index = 0;
126         u32 table_size = 0;
127         struct iwl3945_tpt_entry *tpt_table = NULL;
128
129         if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
130                 rssi = IWL_MIN_RSSI_VAL;
131
132         switch (band) {
133         case IEEE80211_BAND_2GHZ:
134                 tpt_table = iwl3945_tpt_table_g;
135                 table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
136                 break;
137
138         case IEEE80211_BAND_5GHZ:
139                 tpt_table = iwl3945_tpt_table_a;
140                 table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
141                 break;
142
143         default:
144                 BUG();
145                 break;
146         }
147
148         while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
149                 index++;
150
151         index = min(index, (table_size - 1));
152
153         return tpt_table[index].index;
154 }
155
156 static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
157 {
158         window->data = 0;
159         window->success_counter = 0;
160         window->success_ratio = -1;
161         window->counter = 0;
162         window->average_tpt = IWL_INV_TPT;
163         window->stamp = 0;
164 }
165
166 /**
167  * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
168  *
169  * Returns the number of windows that have gathered data but were
170  * not flushed.  If there were any that were not flushed, then
171  * reschedule the rate flushing routine.
172  */
173 static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
174 {
175         int unflushed = 0;
176         int i;
177         unsigned long flags;
178
179         /*
180          * For each rate, if we have collected data on that rate
181          * and it has been more than IWL_RATE_WIN_FLUSH
182          * since we flushed, clear out the gathered statistics
183          */
184         for (i = 0; i < IWL_RATE_COUNT; i++) {
185                 if (!rs_sta->win[i].counter)
186                         continue;
187
188                 spin_lock_irqsave(&rs_sta->lock, flags);
189                 if (time_after(jiffies, rs_sta->win[i].stamp +
190                                IWL_RATE_WIN_FLUSH)) {
191                         IWL_DEBUG_RATE("flushing %d samples of rate "
192                                        "index %d\n",
193                                        rs_sta->win[i].counter, i);
194                         iwl3945_clear_window(&rs_sta->win[i]);
195                 } else
196                         unflushed++;
197                 spin_unlock_irqrestore(&rs_sta->lock, flags);
198         }
199
200         return unflushed;
201 }
202
203 #define IWL_RATE_FLUSH_MAX              5000    /* msec */
204 #define IWL_RATE_FLUSH_MIN              50      /* msec */
205
206 static void iwl3945_bg_rate_scale_flush(unsigned long data)
207 {
208         struct iwl3945_rs_sta *rs_sta = (void *)data;
209         int unflushed = 0;
210         unsigned long flags;
211         u32 packet_count, duration, pps;
212
213         IWL_DEBUG_RATE("enter\n");
214
215         unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
216
217         spin_lock_irqsave(&rs_sta->lock, flags);
218
219         rs_sta->flush_pending = 0;
220
221         /* Number of packets Rx'd since last time this timer ran */
222         packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
223
224         rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
225
226         if (unflushed) {
227                 duration =
228                     jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
229 /*              duration = jiffies_to_msecs(rs_sta->flush_time); */
230
231                 IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
232                                packet_count, duration);
233
234                 /* Determine packets per second */
235                 if (duration)
236                         pps = (packet_count * 1000) / duration;
237                 else
238                         pps = 0;
239
240                 if (pps) {
241                         duration = IWL_RATE_FLUSH_MAX / pps;
242                         if (duration < IWL_RATE_FLUSH_MIN)
243                                 duration = IWL_RATE_FLUSH_MIN;
244                 } else
245                         duration = IWL_RATE_FLUSH_MAX;
246
247                 rs_sta->flush_time = msecs_to_jiffies(duration);
248
249                 IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
250                                duration, packet_count);
251
252                 mod_timer(&rs_sta->rate_scale_flush, jiffies +
253                           rs_sta->flush_time);
254
255                 rs_sta->last_partial_flush = jiffies;
256         }
257
258         /* If there weren't any unflushed entries, we don't schedule the timer
259          * to run again */
260
261         rs_sta->last_flush = jiffies;
262
263         spin_unlock_irqrestore(&rs_sta->lock, flags);
264
265         IWL_DEBUG_RATE("leave\n");
266 }
267
268 /**
269  * iwl3945_collect_tx_data - Update the success/failure sliding window
270  *
271  * We keep a sliding window of the last 64 packets transmitted
272  * at this rate.  window->data contains the bitmask of successful
273  * packets.
274  */
275 static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
276                                 struct iwl3945_rate_scale_data *window,
277                                 int success, int retries)
278 {
279         unsigned long flags;
280
281         if (!retries) {
282                 IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
283                 return;
284         }
285
286         while (retries--) {
287                 spin_lock_irqsave(&rs_sta->lock, flags);
288
289                 /* If we have filled up the window then subtract one from the
290                  * success counter if the high-bit is counting toward
291                  * success */
292                 if (window->counter == IWL_RATE_MAX_WINDOW) {
293                         if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
294                                 window->success_counter--;
295                 } else
296                         window->counter++;
297
298                 /* Slide the window to the left one bit */
299                 window->data = (window->data << 1);
300
301                 /* If this packet was a success then set the low bit high */
302                 if (success) {
303                         window->success_counter++;
304                         window->data |= 1;
305                 }
306
307                 /* window->counter can't be 0 -- it is either >0 or
308                  * IWL_RATE_MAX_WINDOW */
309                 window->success_ratio = 12800 * window->success_counter /
310                     window->counter;
311
312                 /* Tag this window as having been updated */
313                 window->stamp = jiffies;
314
315                 spin_unlock_irqrestore(&rs_sta->lock, flags);
316         }
317 }
318
319 static void rs_rate_init(void *priv_rate, void *priv_sta,
320                          struct ieee80211_local *local, struct sta_info *sta)
321 {
322         int i;
323
324         IWL_DEBUG_RATE("enter\n");
325
326         /* TODO: what is a good starting rate for STA? About middle? Maybe not
327          * the lowest or the highest rate.. Could consider using RSSI from
328          * previous packets? Need to have IEEE 802.1X auth succeed immediately
329          * after assoc.. */
330
331         for (i = IWL_RATE_COUNT - 1; i >= 0; i--) {
332                 if (sta->supp_rates[local->hw.conf.channel->band] & (1 << i)) {
333                         sta->txrate_idx = i;
334                         break;
335                 }
336         }
337
338         sta->last_txrate_idx = sta->txrate_idx;
339
340         /* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
341         if (local->hw.conf.channel->band == IEEE80211_BAND_5GHZ)
342                 sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
343
344         IWL_DEBUG_RATE("leave\n");
345 }
346
347 static void *rs_alloc(struct ieee80211_local *local)
348 {
349         return local->hw.priv;
350 }
351
352 /* rate scale requires free function to be implemented */
353 static void rs_free(void *priv)
354 {
355         return;
356 }
357 static void rs_clear(void *priv)
358 {
359         return;
360 }
361
362
363 static void *rs_alloc_sta(void *priv, gfp_t gfp)
364 {
365         struct iwl3945_rs_sta *rs_sta;
366         int i;
367
368         IWL_DEBUG_RATE("enter\n");
369
370         rs_sta = kzalloc(sizeof(struct iwl3945_rs_sta), gfp);
371         if (!rs_sta) {
372                 IWL_DEBUG_RATE("leave: ENOMEM\n");
373                 return NULL;
374         }
375
376         spin_lock_init(&rs_sta->lock);
377
378         rs_sta->start_rate = IWL_RATE_INVALID;
379
380         /* default to just 802.11b */
381         rs_sta->expected_tpt = iwl3945_expected_tpt_b;
382
383         rs_sta->last_partial_flush = jiffies;
384         rs_sta->last_flush = jiffies;
385         rs_sta->flush_time = IWL_RATE_FLUSH;
386         rs_sta->last_tx_packets = 0;
387         rs_sta->ibss_sta_added = 0;
388
389         init_timer(&rs_sta->rate_scale_flush);
390         rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
391         rs_sta->rate_scale_flush.function = &iwl3945_bg_rate_scale_flush;
392
393         for (i = 0; i < IWL_RATE_COUNT; i++)
394                 iwl3945_clear_window(&rs_sta->win[i]);
395
396         IWL_DEBUG_RATE("leave\n");
397
398         return rs_sta;
399 }
400
401 static void rs_free_sta(void *priv, void *priv_sta)
402 {
403         struct iwl3945_rs_sta *rs_sta = priv_sta;
404
405         IWL_DEBUG_RATE("enter\n");
406         del_timer_sync(&rs_sta->rate_scale_flush);
407         kfree(rs_sta);
408         IWL_DEBUG_RATE("leave\n");
409 }
410
411
412 /*
413  * get ieee prev rate from rate scale table.
414  * for A and B mode we need to overright prev
415  * value
416  */
417 static int rs_adjust_next_rate(struct iwl3945_priv *priv, int rate)
418 {
419         int next_rate = iwl3945_get_prev_ieee_rate(rate);
420
421         switch (priv->band) {
422         case IEEE80211_BAND_5GHZ:
423                 if (rate == IWL_RATE_12M_INDEX)
424                         next_rate = IWL_RATE_9M_INDEX;
425                 else if (rate == IWL_RATE_6M_INDEX)
426                         next_rate = IWL_RATE_6M_INDEX;
427                 break;
428 /* XXX cannot be invoked in current mac80211 so not a regression
429         case MODE_IEEE80211B:
430                 if (rate == IWL_RATE_11M_INDEX_TABLE)
431                         next_rate = IWL_RATE_5M_INDEX_TABLE;
432                 break;
433  */
434         default:
435                 break;
436         }
437
438         return next_rate;
439 }
440 /**
441  * rs_tx_status - Update rate control values based on Tx results
442  *
443  * NOTE: Uses iwl3945_priv->retry_rate for the # of retries attempted by
444  * the hardware for each rate.
445  */
446 static void rs_tx_status(void *priv_rate,
447                          struct net_device *dev,
448                          struct sk_buff *skb)
449 {
450         u8 retries, current_count;
451         int scale_rate_index, first_index, last_index;
452         unsigned long flags;
453         struct sta_info *sta;
454         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
455         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
456         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
457         struct iwl3945_rs_sta *rs_sta;
458         struct ieee80211_supported_band *sband;
459         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
460
461         IWL_DEBUG_RATE("enter\n");
462
463         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
464
465
466         retries = info->status.retry_count;
467         first_index = sband->bitrates[info->tx_rate_idx].hw_value;
468         if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
469                 IWL_DEBUG_RATE("leave: Rate out of bounds: %d\n", first_index);
470                 return;
471         }
472
473         rcu_read_lock();
474
475         sta = sta_info_get(local, hdr->addr1);
476         if (!sta || !sta->rate_ctrl_priv) {
477                 rcu_read_unlock();
478                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
479                 return;
480         }
481
482         rs_sta = (void *)sta->rate_ctrl_priv;
483
484         rs_sta->tx_packets++;
485
486         scale_rate_index = first_index;
487         last_index = first_index;
488
489         /*
490          * Update the window for each rate.  We determine which rates
491          * were Tx'd based on the total number of retries vs. the number
492          * of retries configured for each rate -- currently set to the
493          * priv value 'retry_rate' vs. rate specific
494          *
495          * On exit from this while loop last_index indicates the rate
496          * at which the frame was finally transmitted (or failed if no
497          * ACK)
498          */
499         while (retries > 0) {
500                 if (retries < priv->retry_rate) {
501                         current_count = retries;
502                         last_index = scale_rate_index;
503                 } else {
504                         current_count = priv->retry_rate;
505                         last_index = rs_adjust_next_rate(priv,
506                                                          scale_rate_index);
507                 }
508
509                 /* Update this rate accounting for as many retries
510                  * as was used for it (per current_count) */
511                 iwl3945_collect_tx_data(rs_sta,
512                                     &rs_sta->win[scale_rate_index],
513                                     0, current_count);
514                 IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
515                                scale_rate_index, current_count);
516
517                 retries -= current_count;
518
519                 if (retries)
520                         scale_rate_index =
521                             rs_adjust_next_rate(priv, scale_rate_index);
522         }
523
524
525         /* Update the last index window with success/failure based on ACK */
526         IWL_DEBUG_RATE("Update rate %d with %s.\n",
527                        last_index,
528                        (info->flags & IEEE80211_TX_STAT_ACK) ?
529                        "success" : "failure");
530         iwl3945_collect_tx_data(rs_sta,
531                             &rs_sta->win[last_index],
532                             info->flags & IEEE80211_TX_STAT_ACK, 1);
533
534         /* We updated the rate scale window -- if its been more than
535          * flush_time since the last run, schedule the flush
536          * again */
537         spin_lock_irqsave(&rs_sta->lock, flags);
538
539         if (!rs_sta->flush_pending &&
540             time_after(jiffies, rs_sta->last_partial_flush +
541                        rs_sta->flush_time)) {
542
543                 rs_sta->flush_pending = 1;
544                 mod_timer(&rs_sta->rate_scale_flush,
545                           jiffies + rs_sta->flush_time);
546         }
547
548         spin_unlock_irqrestore(&rs_sta->lock, flags);
549
550         rcu_read_unlock();
551
552         IWL_DEBUG_RATE("leave\n");
553
554         return;
555 }
556
557 static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
558                                  u8 index, u16 rate_mask, enum ieee80211_band band)
559 {
560         u8 high = IWL_RATE_INVALID;
561         u8 low = IWL_RATE_INVALID;
562
563         /* 802.11A walks to the next literal adjacent rate in
564          * the rate table */
565         if (unlikely(band == IEEE80211_BAND_5GHZ)) {
566                 int i;
567                 u32 mask;
568
569                 /* Find the previous rate that is in the rate mask */
570                 i = index - 1;
571                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
572                         if (rate_mask & mask) {
573                                 low = i;
574                                 break;
575                         }
576                 }
577
578                 /* Find the next rate that is in the rate mask */
579                 i = index + 1;
580                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
581                         if (rate_mask & mask) {
582                                 high = i;
583                                 break;
584                         }
585                 }
586
587                 return (high << 8) | low;
588         }
589
590         low = index;
591         while (low != IWL_RATE_INVALID) {
592                 if (rs_sta->tgg)
593                         low = iwl3945_rates[low].prev_rs_tgg;
594                 else
595                         low = iwl3945_rates[low].prev_rs;
596                 if (low == IWL_RATE_INVALID)
597                         break;
598                 if (rate_mask & (1 << low))
599                         break;
600                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
601         }
602
603         high = index;
604         while (high != IWL_RATE_INVALID) {
605                 if (rs_sta->tgg)
606                         high = iwl3945_rates[high].next_rs_tgg;
607                 else
608                         high = iwl3945_rates[high].next_rs;
609                 if (high == IWL_RATE_INVALID)
610                         break;
611                 if (rate_mask & (1 << high))
612                         break;
613                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
614         }
615
616         return (high << 8) | low;
617 }
618
619 /**
620  * rs_get_rate - find the rate for the requested packet
621  *
622  * Returns the ieee80211_rate structure allocated by the driver.
623  *
624  * The rate control algorithm has no internal mapping between hw_mode's
625  * rate ordering and the rate ordering used by the rate control algorithm.
626  *
627  * The rate control algorithm uses a single table of rates that goes across
628  * the entire A/B/G spectrum vs. being limited to just one particular
629  * hw_mode.
630  *
631  * As such, we can't convert the index obtained below into the hw_mode's
632  * rate table and must reference the driver allocated rate table
633  *
634  */
635 static void rs_get_rate(void *priv_rate, struct net_device *dev,
636                         struct ieee80211_supported_band *sband,
637                         struct sk_buff *skb,
638                         struct rate_selection *sel)
639 {
640         u8 low = IWL_RATE_INVALID;
641         u8 high = IWL_RATE_INVALID;
642         u16 high_low;
643         int index;
644         struct iwl3945_rs_sta *rs_sta;
645         struct iwl3945_rate_scale_data *window = NULL;
646         int current_tpt = IWL_INV_TPT;
647         int low_tpt = IWL_INV_TPT;
648         int high_tpt = IWL_INV_TPT;
649         u32 fail_count;
650         s8 scale_action = 0;
651         unsigned long flags;
652         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
653         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
654         struct sta_info *sta;
655         u16 fc, rate_mask;
656         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
657         DECLARE_MAC_BUF(mac);
658
659         IWL_DEBUG_RATE("enter\n");
660
661         rcu_read_lock();
662
663         sta = sta_info_get(local, hdr->addr1);
664
665         /* Send management frames and broadcast/multicast data using lowest
666          * rate. */
667         fc = le16_to_cpu(hdr->frame_control);
668         if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
669             is_multicast_ether_addr(hdr->addr1) ||
670             !sta || !sta->rate_ctrl_priv) {
671                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
672                 sel->rate_idx = rate_lowest_index(local, sband, sta);
673                 rcu_read_unlock();
674                 return;
675         }
676
677         rate_mask = sta->supp_rates[sband->band];
678         index = min(sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT - 1);
679
680         if (sband->band == IEEE80211_BAND_5GHZ)
681                 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
682
683         rs_sta = (void *)sta->rate_ctrl_priv;
684
685         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
686             !rs_sta->ibss_sta_added) {
687                 u8 sta_id = iwl3945_hw_find_station(priv, hdr->addr1);
688
689                 if (sta_id == IWL_INVALID_STATION) {
690                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
691                                        print_mac(mac, hdr->addr1));
692                         sta_id = iwl3945_add_station(priv,
693                                     hdr->addr1, 0, CMD_ASYNC);
694                 }
695                 if (sta_id != IWL_INVALID_STATION)
696                         rs_sta->ibss_sta_added = 1;
697         }
698
699         spin_lock_irqsave(&rs_sta->lock, flags);
700
701         if (rs_sta->start_rate != IWL_RATE_INVALID) {
702                 index = rs_sta->start_rate;
703                 rs_sta->start_rate = IWL_RATE_INVALID;
704         }
705
706         window = &(rs_sta->win[index]);
707
708         fail_count = window->counter - window->success_counter;
709
710         if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
711              (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
712                 window->average_tpt = IWL_INV_TPT;
713                 spin_unlock_irqrestore(&rs_sta->lock, flags);
714
715                 IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
716                                "counter: %d, success_counter: %d, "
717                                "expected_tpt is %sNULL\n",
718                                index,
719                                window->counter,
720                                window->success_counter,
721                                rs_sta->expected_tpt ? "not " : "");
722                 goto out;
723
724         }
725
726         window->average_tpt = ((window->success_ratio *
727                                 rs_sta->expected_tpt[index] + 64) / 128);
728         current_tpt = window->average_tpt;
729
730         high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
731                                              sband->band);
732         low = high_low & 0xff;
733         high = (high_low >> 8) & 0xff;
734
735         if (low != IWL_RATE_INVALID)
736                 low_tpt = rs_sta->win[low].average_tpt;
737
738         if (high != IWL_RATE_INVALID)
739                 high_tpt = rs_sta->win[high].average_tpt;
740
741         spin_unlock_irqrestore(&rs_sta->lock, flags);
742
743         scale_action = 1;
744
745         if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
746                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
747                 scale_action = -1;
748         } else if ((low_tpt == IWL_INV_TPT) && (high_tpt == IWL_INV_TPT))
749                 scale_action = 1;
750         else if ((low_tpt != IWL_INV_TPT) && (high_tpt != IWL_INV_TPT) &&
751                  (low_tpt < current_tpt) && (high_tpt < current_tpt)) {
752                 IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
753                                "current_tpt [%d]\n",
754                                low_tpt, high_tpt, current_tpt);
755                 scale_action = 0;
756         } else {
757                 if (high_tpt != IWL_INV_TPT) {
758                         if (high_tpt > current_tpt)
759                                 scale_action = 1;
760                         else {
761                                 IWL_DEBUG_RATE
762                                     ("decrease rate because of high tpt\n");
763                                 scale_action = -1;
764                         }
765                 } else if (low_tpt != IWL_INV_TPT) {
766                         if (low_tpt > current_tpt) {
767                                 IWL_DEBUG_RATE
768                                     ("decrease rate because of low tpt\n");
769                                 scale_action = -1;
770                         } else
771                                 scale_action = 1;
772                 }
773         }
774
775         if ((window->success_ratio > IWL_RATE_HIGH_TH) ||
776             (current_tpt > window->average_tpt)) {
777                 IWL_DEBUG_RATE("No action -- success_ratio [%d] > HIGH_TH or "
778                                "current_tpt [%d] > average_tpt [%d]\n",
779                                window->success_ratio,
780                                current_tpt, window->average_tpt);
781                 scale_action = 0;
782         }
783
784         switch (scale_action) {
785         case -1:
786                 if (low != IWL_RATE_INVALID)
787                         index = low;
788                 break;
789
790         case 1:
791                 if (high != IWL_RATE_INVALID)
792                         index = high;
793
794                 break;
795
796         case 0:
797         default:
798                 break;
799         }
800
801         IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
802                        index, scale_action, low, high);
803
804  out:
805
806         sta->last_txrate_idx = index;
807         if (sband->band == IEEE80211_BAND_5GHZ)
808                 sta->txrate_idx = sta->last_txrate_idx - IWL_FIRST_OFDM_RATE;
809         else
810                 sta->txrate_idx = sta->last_txrate_idx;
811
812         rcu_read_unlock();
813
814         IWL_DEBUG_RATE("leave: %d\n", index);
815
816         sel->rate_idx = sta->txrate_idx;
817 }
818
819 static struct rate_control_ops rs_ops = {
820         .module = NULL,
821         .name = RS_NAME,
822         .tx_status = rs_tx_status,
823         .get_rate = rs_get_rate,
824         .rate_init = rs_rate_init,
825         .clear = rs_clear,
826         .alloc = rs_alloc,
827         .free = rs_free,
828         .alloc_sta = rs_alloc_sta,
829         .free_sta = rs_free_sta,
830 };
831
832 int iwl3945_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
833 {
834         struct ieee80211_local *local = hw_to_local(hw);
835         struct iwl3945_priv *priv = hw->priv;
836         struct iwl3945_rs_sta *rs_sta;
837         struct sta_info *sta;
838         unsigned long flags;
839         int count = 0, i;
840         u32 samples = 0, success = 0, good = 0;
841         unsigned long now = jiffies;
842         u32 max_time = 0;
843
844         rcu_read_lock();
845
846         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
847         if (!sta || !sta->rate_ctrl_priv) {
848                 if (sta)
849                         IWL_DEBUG_RATE("leave - no private rate data!\n");
850                 else
851                         IWL_DEBUG_RATE("leave - no station!\n");
852                 rcu_read_unlock();
853                 return sprintf(buf, "station %d not found\n", sta_id);
854         }
855
856         rs_sta = (void *)sta->rate_ctrl_priv;
857         spin_lock_irqsave(&rs_sta->lock, flags);
858         i = IWL_RATE_54M_INDEX;
859         while (1) {
860                 u64 mask;
861                 int j;
862
863                 count +=
864                     sprintf(&buf[count], " %2dMbs: ", iwl3945_rates[i].ieee / 2);
865
866                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
867                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
868                         buf[count++] =
869                             (rs_sta->win[i].data & mask) ? '1' : '0';
870
871                 samples += rs_sta->win[i].counter;
872                 good += rs_sta->win[i].success_counter;
873                 success += rs_sta->win[i].success_counter *
874                                                 iwl3945_rates[i].ieee;
875
876                 if (rs_sta->win[i].stamp) {
877                         int delta =
878                             jiffies_to_msecs(now - rs_sta->win[i].stamp);
879
880                         if (delta > max_time)
881                                 max_time = delta;
882
883                         count += sprintf(&buf[count], "%5dms\n", delta);
884                 } else
885                         buf[count++] = '\n';
886
887                 j = iwl3945_get_prev_ieee_rate(i);
888                 if (j == i)
889                         break;
890                 i = j;
891         }
892         spin_unlock_irqrestore(&rs_sta->lock, flags);
893         rcu_read_unlock();
894
895         /* Display the average rate of all samples taken.
896          *
897          * NOTE:  We multiple # of samples by 2 since the IEEE measurement
898          * added from iwl3945_rates is actually 2X the rate */
899         if (samples)
900                 count += sprintf(
901                         &buf[count],
902                         "\nAverage rate is %3d.%02dMbs over last %4dms\n"
903                         "%3d%% success (%d good packets over %d tries)\n",
904                         success / (2 * samples), (success * 5 / samples) % 10,
905                         max_time, good * 100 / samples, good, samples);
906         else
907                 count += sprintf(&buf[count], "\nAverage rate: 0Mbs\n");
908
909         return count;
910 }
911
912 void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
913 {
914         struct iwl3945_priv *priv = hw->priv;
915         s32 rssi = 0;
916         unsigned long flags;
917         struct ieee80211_local *local = hw_to_local(hw);
918         struct iwl3945_rs_sta *rs_sta;
919         struct sta_info *sta;
920
921         IWL_DEBUG_RATE("enter\n");
922
923         if (!local->rate_ctrl->ops->name ||
924             strcmp(local->rate_ctrl->ops->name, RS_NAME)) {
925                 IWL_WARNING("iwl-3945-rs not selected as rate control algo!\n");
926                 IWL_DEBUG_RATE("leave - mac80211 picked the wrong RC algo.\n");
927                 return;
928         }
929
930         rcu_read_lock();
931
932         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
933         if (!sta || !sta->rate_ctrl_priv) {
934                 IWL_DEBUG_RATE("leave - no private rate data!\n");
935                 rcu_read_unlock();
936                 return;
937         }
938
939         rs_sta = (void *)sta->rate_ctrl_priv;
940
941         spin_lock_irqsave(&rs_sta->lock, flags);
942
943         rs_sta->tgg = 0;
944         switch (priv->band) {
945         case IEEE80211_BAND_2GHZ:
946                 /* TODO: this always does G, not a regression */
947                 if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
948                         rs_sta->tgg = 1;
949                         rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
950                 } else
951                         rs_sta->expected_tpt = iwl3945_expected_tpt_g;
952                 break;
953
954         case IEEE80211_BAND_5GHZ:
955                 rs_sta->expected_tpt = iwl3945_expected_tpt_a;
956                 break;
957         case IEEE80211_NUM_BANDS:
958                 BUG();
959                 break;
960         }
961
962         rcu_read_unlock();
963         spin_unlock_irqrestore(&rs_sta->lock, flags);
964
965         rssi = priv->last_rx_rssi;
966         if (rssi == 0)
967                 rssi = IWL_MIN_RSSI_VAL;
968
969         IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
970
971         rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
972
973         IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
974                        "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
975                        iwl3945_rates[rs_sta->start_rate].plcp);
976 }
977
978 int iwl3945_rate_control_register(void)
979 {
980         return ieee80211_rate_control_register(&rs_ops);
981 }
982
983 void iwl3945_rate_control_unregister(void)
984 {
985         ieee80211_rate_control_unregister(&rs_ops);
986 }
987
988