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Staging: netwave: delete the driver
[linux/fpc-iii.git] / drivers / net / wireless / iwlwifi / iwl-3945-rs.c
blob902c4d4293e9634bbcfd135c880c79d7a3b27772
1 /******************************************************************************
2 *
3 * Copyright(c) 2005 - 2010 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 * Intel Linux Wireless <ilw@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/slab.h>
31 #include <linux/wireless.h>
32 #include <net/mac80211.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 "iwl-commands.h"
41 #include "iwl-3945.h"
42 #include "iwl-sta.h"
43
44 #define RS_NAME "iwl-3945-rs"
45
46 static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT_3945] = {
47 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
48 };
49
50 static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT_3945] = {
51 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
52 };
53
54 static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT_3945] = {
55 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
56 };
57
58 static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT_3945] = {
59 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
60 };
61
62 struct iwl3945_tpt_entry {
63 s8 min_rssi;
64 u8 index;
65 };
66
67 static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
68 {-60, IWL_RATE_54M_INDEX},
69 {-64, IWL_RATE_48M_INDEX},
70 {-72, IWL_RATE_36M_INDEX},
71 {-80, IWL_RATE_24M_INDEX},
72 {-84, IWL_RATE_18M_INDEX},
73 {-85, IWL_RATE_12M_INDEX},
74 {-87, IWL_RATE_9M_INDEX},
75 {-89, IWL_RATE_6M_INDEX}
76 };
77
78 static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
79 {-60, IWL_RATE_54M_INDEX},
80 {-64, IWL_RATE_48M_INDEX},
81 {-68, IWL_RATE_36M_INDEX},
82 {-80, IWL_RATE_24M_INDEX},
83 {-84, IWL_RATE_18M_INDEX},
84 {-85, IWL_RATE_12M_INDEX},
85 {-86, IWL_RATE_11M_INDEX},
86 {-88, IWL_RATE_5M_INDEX},
87 {-90, IWL_RATE_2M_INDEX},
88 {-92, IWL_RATE_1M_INDEX}
89 };
90
91 #define IWL_RATE_MAX_WINDOW 62
92 #define IWL_RATE_FLUSH (3*HZ)
93 #define IWL_RATE_WIN_FLUSH (HZ/2)
94 #define IWL39_RATE_HIGH_TH 11520
95 #define IWL_SUCCESS_UP_TH 8960
96 #define IWL_SUCCESS_DOWN_TH 10880
97 #define IWL_RATE_MIN_FAILURE_TH 6
98 #define IWL_RATE_MIN_SUCCESS_TH 8
99 #define IWL_RATE_DECREASE_TH 1920
100 #define IWL_RATE_RETRY_TH 15
101
102 static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, enum ieee80211_band band)
103 {
104 u32 index = 0;
105 u32 table_size = 0;
106 struct iwl3945_tpt_entry *tpt_table = NULL;
107
108 if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
109 rssi = IWL_MIN_RSSI_VAL;
110
111 switch (band) {
112 case IEEE80211_BAND_2GHZ:
113 tpt_table = iwl3945_tpt_table_g;
114 table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
115 break;
116
117 case IEEE80211_BAND_5GHZ:
118 tpt_table = iwl3945_tpt_table_a;
119 table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
120 break;
121
122 default:
123 BUG();
124 break;
125 }
126
127 while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
128 index++;
129
130 index = min(index, (table_size - 1));
131
132 return tpt_table[index].index;
133 }
134
135 static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
136 {
137 window->data = 0;
138 window->success_counter = 0;
139 window->success_ratio = -1;
140 window->counter = 0;
141 window->average_tpt = IWL_INVALID_VALUE;
142 window->stamp = 0;
143 }
144
145 /**
146 * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
147 *
148 * Returns the number of windows that have gathered data but were
149 * not flushed. If there were any that were not flushed, then
150 * reschedule the rate flushing routine.
151 */
152 static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
153 {
154 int unflushed = 0;
155 int i;
156 unsigned long flags;
157 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
158
159 /*
160 * For each rate, if we have collected data on that rate
161 * and it has been more than IWL_RATE_WIN_FLUSH
162 * since we flushed, clear out the gathered statistics
163 */
164 for (i = 0; i < IWL_RATE_COUNT_3945; i++) {
165 if (!rs_sta->win[i].counter)
166 continue;
167
168 spin_lock_irqsave(&rs_sta->lock, flags);
169 if (time_after(jiffies, rs_sta->win[i].stamp +
170 IWL_RATE_WIN_FLUSH)) {
171 IWL_DEBUG_RATE(priv, "flushing %d samples of rate "
172 "index %d\n",
173 rs_sta->win[i].counter, i);
174 iwl3945_clear_window(&rs_sta->win[i]);
175 } else
176 unflushed++;
177 spin_unlock_irqrestore(&rs_sta->lock, flags);
178 }
179
180 return unflushed;
181 }
182
183 #define IWL_RATE_FLUSH_MAX 5000 /* msec */
184 #define IWL_RATE_FLUSH_MIN 50 /* msec */
185 #define IWL_AVERAGE_PACKETS 1500
186
187 static void iwl3945_bg_rate_scale_flush(unsigned long data)
188 {
189 struct iwl3945_rs_sta *rs_sta = (void *)data;
190 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
191 int unflushed = 0;
192 unsigned long flags;
193 u32 packet_count, duration, pps;
194
195 IWL_DEBUG_RATE(priv, "enter\n");
196
197 unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
198
199 spin_lock_irqsave(&rs_sta->lock, flags);
200
201 /* Number of packets Rx'd since last time this timer ran */
202 packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
203
204 rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
205
206 if (unflushed) {
207 duration =
208 jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
209
210 IWL_DEBUG_RATE(priv, "Tx'd %d packets in %dms\n",
211 packet_count, duration);
212
213 /* Determine packets per second */
214 if (duration)
215 pps = (packet_count * 1000) / duration;
216 else
217 pps = 0;
218
219 if (pps) {
220 duration = (IWL_AVERAGE_PACKETS * 1000) / pps;
221 if (duration < IWL_RATE_FLUSH_MIN)
222 duration = IWL_RATE_FLUSH_MIN;
223 else if (duration > IWL_RATE_FLUSH_MAX)
224 duration = IWL_RATE_FLUSH_MAX;
225 } else
226 duration = IWL_RATE_FLUSH_MAX;
227
228 rs_sta->flush_time = msecs_to_jiffies(duration);
229
230 IWL_DEBUG_RATE(priv, "new flush period: %d msec ave %d\n",
231 duration, packet_count);
232
233 mod_timer(&rs_sta->rate_scale_flush, jiffies +
234 rs_sta->flush_time);
235
236 rs_sta->last_partial_flush = jiffies;
237 } else {
238 rs_sta->flush_time = IWL_RATE_FLUSH;
239 rs_sta->flush_pending = 0;
240 }
241 /* If there weren't any unflushed entries, we don't schedule the timer
242 * to run again */
243
244 rs_sta->last_flush = jiffies;
245
246 spin_unlock_irqrestore(&rs_sta->lock, flags);
247
248 IWL_DEBUG_RATE(priv, "leave\n");
249 }
250
251 /**
252 * iwl3945_collect_tx_data - Update the success/failure sliding window
253 *
254 * We keep a sliding window of the last 64 packets transmitted
255 * at this rate. window->data contains the bitmask of successful
256 * packets.
257 */
258 static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
259 struct iwl3945_rate_scale_data *window,
260 int success, int retries, int index)
261 {
262 unsigned long flags;
263 s32 fail_count;
264 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
265
266 if (!retries) {
267 IWL_DEBUG_RATE(priv, "leave: retries == 0 -- should be at least 1\n");
268 return;
269 }
270
271 spin_lock_irqsave(&rs_sta->lock, flags);
272
273 /*
274 * Keep track of only the latest 62 tx frame attempts in this rate's
275 * history window; anything older isn't really relevant any more.
276 * If we have filled up the sliding window, drop the oldest attempt;
277 * if the oldest attempt (highest bit in bitmap) shows "success",
278 * subtract "1" from the success counter (this is the main reason
279 * we keep these bitmaps!).
280 * */
281 while (retries > 0) {
282 if (window->counter >= IWL_RATE_MAX_WINDOW) {
283
284 /* remove earliest */
285 window->counter = IWL_RATE_MAX_WINDOW - 1;
286
287 if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1))) {
288 window->data &= ~(1ULL << (IWL_RATE_MAX_WINDOW - 1));
289 window->success_counter--;
290 }
291 }
292
293 /* Increment frames-attempted counter */
294 window->counter++;
295
296 /* Shift bitmap by one frame (throw away oldest history),
297 * OR in "1", and increment "success" if this
298 * frame was successful. */
299 window->data <<= 1;
300 if (success > 0) {
301 window->success_counter++;
302 window->data |= 0x1;
303 success--;
304 }
305
306 retries--;
307 }
308
309 /* Calculate current success ratio, avoid divide-by-0! */
310 if (window->counter > 0)
311 window->success_ratio = 128 * (100 * window->success_counter)
312 / window->counter;
313 else
314 window->success_ratio = IWL_INVALID_VALUE;
315
316 fail_count = window->counter - window->success_counter;
317
318 /* Calculate average throughput, if we have enough history. */
319 if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
320 (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
321 window->average_tpt = ((window->success_ratio *
322 rs_sta->expected_tpt[index] + 64) / 128);
323 else
324 window->average_tpt = IWL_INVALID_VALUE;
325
326 /* Tag this window as having been updated */
327 window->stamp = jiffies;
328
329 spin_unlock_irqrestore(&rs_sta->lock, flags);
330
331 }
332
333 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
334 struct ieee80211_sta *sta, void *priv_sta)
335 {
336 struct iwl3945_rs_sta *rs_sta = priv_sta;
337 struct iwl_priv *priv = (struct iwl_priv *)priv_r;
338 int i;
339
340 IWL_DEBUG_RATE(priv, "enter\n");
341
342 spin_lock_init(&rs_sta->lock);
343
344 rs_sta->priv = priv;
345
346 rs_sta->start_rate = IWL_RATE_INVALID;
347
348 /* default to just 802.11b */
349 rs_sta->expected_tpt = iwl3945_expected_tpt_b;
350
351 rs_sta->last_partial_flush = jiffies;
352 rs_sta->last_flush = jiffies;
353 rs_sta->flush_time = IWL_RATE_FLUSH;
354 rs_sta->last_tx_packets = 0;
355 rs_sta->ibss_sta_added = 0;
356
357 init_timer(&rs_sta->rate_scale_flush);
358 rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
359 rs_sta->rate_scale_flush.function = iwl3945_bg_rate_scale_flush;
360
361 for (i = 0; i < IWL_RATE_COUNT_3945; i++)
362 iwl3945_clear_window(&rs_sta->win[i]);
363
364 /* TODO: what is a good starting rate for STA? About middle? Maybe not
365 * the lowest or the highest rate.. Could consider using RSSI from
366 * previous packets? Need to have IEEE 802.1X auth succeed immediately
367 * after assoc.. */
368
369 for (i = sband->n_bitrates - 1; i >= 0; i--) {
370 if (sta->supp_rates[sband->band] & (1 << i)) {
371 rs_sta->last_txrate_idx = i;
372 break;
373 }
374 }
375
376 priv->sta_supp_rates = sta->supp_rates[sband->band];
377 /* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
378 if (sband->band == IEEE80211_BAND_5GHZ) {
379 rs_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
380 priv->sta_supp_rates = priv->sta_supp_rates <<
381 IWL_FIRST_OFDM_RATE;
382 }
383
384
385 IWL_DEBUG_RATE(priv, "leave\n");
386 }
387
388 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
389 {
390 return hw->priv;
391 }
392
393 /* rate scale requires free function to be implemented */
394 static void rs_free(void *priv)
395 {
396 return;
397 }
398
399 static void *rs_alloc_sta(void *iwl_priv, struct ieee80211_sta *sta, gfp_t gfp)
400 {
401 struct iwl3945_rs_sta *rs_sta;
402 struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
403 struct iwl_priv *priv __maybe_unused = iwl_priv;
404
405 IWL_DEBUG_RATE(priv, "enter\n");
406
407 rs_sta = &psta->rs_sta;
408
409 IWL_DEBUG_RATE(priv, "leave\n");
410
411 return rs_sta;
412 }
413
414 static void rs_free_sta(void *iwl_priv, struct ieee80211_sta *sta,
415 void *priv_sta)
416 {
417 struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
418 struct iwl3945_rs_sta *rs_sta = &psta->rs_sta;
419 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
420
421 IWL_DEBUG_RATE(priv, "enter\n");
422 del_timer_sync(&rs_sta->rate_scale_flush);
423 IWL_DEBUG_RATE(priv, "leave\n");
424 }
425
426
427 /**
428 * rs_tx_status - Update rate control values based on Tx results
429 *
430 * NOTE: Uses iwl_priv->retry_rate for the # of retries attempted by
431 * the hardware for each rate.
432 */
433 static void rs_tx_status(void *priv_rate, struct ieee80211_supported_band *sband,
434 struct ieee80211_sta *sta, void *priv_sta,
435 struct sk_buff *skb)
436 {
437 s8 retries = 0, current_count;
438 int scale_rate_index, first_index, last_index;
439 unsigned long flags;
440 struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
441 struct iwl3945_rs_sta *rs_sta = priv_sta;
442 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
443
444 IWL_DEBUG_RATE(priv, "enter\n");
445
446 retries = info->status.rates[0].count;
447 /* Sanity Check for retries */
448 if (retries > IWL_RATE_RETRY_TH)
449 retries = IWL_RATE_RETRY_TH;
450
451 first_index = sband->bitrates[info->status.rates[0].idx].hw_value;
452 if ((first_index < 0) || (first_index >= IWL_RATE_COUNT_3945)) {
453 IWL_DEBUG_RATE(priv, "leave: Rate out of bounds: %d\n", first_index);
454 return;
455 }
456
457 if (!priv_sta) {
458 IWL_DEBUG_RATE(priv, "leave: No STA priv data to update!\n");
459 return;
460 }
461
462 rs_sta->tx_packets++;
463
464 scale_rate_index = first_index;
465 last_index = first_index;
466
467 /*
468 * Update the window for each rate. We determine which rates
469 * were Tx'd based on the total number of retries vs. the number
470 * of retries configured for each rate -- currently set to the
471 * priv value 'retry_rate' vs. rate specific
472 *
473 * On exit from this while loop last_index indicates the rate
474 * at which the frame was finally transmitted (or failed if no
475 * ACK)
476 */
477 while (retries > 1) {
478 if ((retries - 1) < priv->retry_rate) {
479 current_count = (retries - 1);
480 last_index = scale_rate_index;
481 } else {
482 current_count = priv->retry_rate;
483 last_index = iwl3945_rs_next_rate(priv,
484 scale_rate_index);
485 }
486
487 /* Update this rate accounting for as many retries
488 * as was used for it (per current_count) */
489 iwl3945_collect_tx_data(rs_sta,
490 &rs_sta->win[scale_rate_index],
491 0, current_count, scale_rate_index);
492 IWL_DEBUG_RATE(priv, "Update rate %d for %d retries.\n",
493 scale_rate_index, current_count);
494
495 retries -= current_count;
496
497 scale_rate_index = last_index;
498 }
499
500
501 /* Update the last index window with success/failure based on ACK */
502 IWL_DEBUG_RATE(priv, "Update rate %d with %s.\n",
503 last_index,
504 (info->flags & IEEE80211_TX_STAT_ACK) ?
505 "success" : "failure");
506 iwl3945_collect_tx_data(rs_sta,
507 &rs_sta->win[last_index],
508 info->flags & IEEE80211_TX_STAT_ACK, 1, last_index);
509
510 /* We updated the rate scale window -- if its been more than
511 * flush_time since the last run, schedule the flush
512 * again */
513 spin_lock_irqsave(&rs_sta->lock, flags);
514
515 if (!rs_sta->flush_pending &&
516 time_after(jiffies, rs_sta->last_flush +
517 rs_sta->flush_time)) {
518
519 rs_sta->last_partial_flush = jiffies;
520 rs_sta->flush_pending = 1;
521 mod_timer(&rs_sta->rate_scale_flush,
522 jiffies + rs_sta->flush_time);
523 }
524
525 spin_unlock_irqrestore(&rs_sta->lock, flags);
526
527 IWL_DEBUG_RATE(priv, "leave\n");
528
529 return;
530 }
531
532 static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
533 u8 index, u16 rate_mask, enum ieee80211_band band)
534 {
535 u8 high = IWL_RATE_INVALID;
536 u8 low = IWL_RATE_INVALID;
537 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
538
539 /* 802.11A walks to the next literal adjacent rate in
540 * the rate table */
541 if (unlikely(band == IEEE80211_BAND_5GHZ)) {
542 int i;
543 u32 mask;
544
545 /* Find the previous rate that is in the rate mask */
546 i = index - 1;
547 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
548 if (rate_mask & mask) {
549 low = i;
550 break;
551 }
552 }
553
554 /* Find the next rate that is in the rate mask */
555 i = index + 1;
556 for (mask = (1 << i); i < IWL_RATE_COUNT_3945;
557 i++, mask <<= 1) {
558 if (rate_mask & mask) {
559 high = i;
560 break;
561 }
562 }
563
564 return (high << 8) | low;
565 }
566
567 low = index;
568 while (low != IWL_RATE_INVALID) {
569 if (rs_sta->tgg)
570 low = iwl3945_rates[low].prev_rs_tgg;
571 else
572 low = iwl3945_rates[low].prev_rs;
573 if (low == IWL_RATE_INVALID)
574 break;
575 if (rate_mask & (1 << low))
576 break;
577 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
578 }
579
580 high = index;
581 while (high != IWL_RATE_INVALID) {
582 if (rs_sta->tgg)
583 high = iwl3945_rates[high].next_rs_tgg;
584 else
585 high = iwl3945_rates[high].next_rs;
586 if (high == IWL_RATE_INVALID)
587 break;
588 if (rate_mask & (1 << high))
589 break;
590 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
591 }
592
593 return (high << 8) | low;
594 }
595
596 /**
597 * rs_get_rate - find the rate for the requested packet
598 *
599 * Returns the ieee80211_rate structure allocated by the driver.
600 *
601 * The rate control algorithm has no internal mapping between hw_mode's
602 * rate ordering and the rate ordering used by the rate control algorithm.
603 *
604 * The rate control algorithm uses a single table of rates that goes across
605 * the entire A/B/G spectrum vs. being limited to just one particular
606 * hw_mode.
607 *
608 * As such, we can't convert the index obtained below into the hw_mode's
609 * rate table and must reference the driver allocated rate table
610 *
611 */
612 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta,
613 void *priv_sta, struct ieee80211_tx_rate_control *txrc)
614 {
615 struct ieee80211_supported_band *sband = txrc->sband;
616 struct sk_buff *skb = txrc->skb;
617 u8 low = IWL_RATE_INVALID;
618 u8 high = IWL_RATE_INVALID;
619 u16 high_low;
620 int index;
621 struct iwl3945_rs_sta *rs_sta = priv_sta;
622 struct iwl3945_rate_scale_data *window = NULL;
623 int current_tpt = IWL_INVALID_VALUE;
624 int low_tpt = IWL_INVALID_VALUE;
625 int high_tpt = IWL_INVALID_VALUE;
626 u32 fail_count;
627 s8 scale_action = 0;
628 unsigned long flags;
629 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
630 u16 rate_mask = sta ? sta->supp_rates[sband->band] : 0;
631 s8 max_rate_idx = -1;
632 struct iwl_priv *priv = (struct iwl_priv *)priv_r;
633 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
634
635 IWL_DEBUG_RATE(priv, "enter\n");
636
637 if (rate_control_send_low(sta, priv_sta, txrc))
638 return;
639
640 rate_mask = sta->supp_rates[sband->band];
641
642 /* get user max rate if set */
643 max_rate_idx = txrc->max_rate_idx;
644 if ((sband->band == IEEE80211_BAND_5GHZ) && (max_rate_idx != -1))
645 max_rate_idx += IWL_FIRST_OFDM_RATE;
646 if ((max_rate_idx < 0) || (max_rate_idx >= IWL_RATE_COUNT))
647 max_rate_idx = -1;
648
649 index = min(rs_sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT_3945 - 1);
650
651 if (sband->band == IEEE80211_BAND_5GHZ)
652 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
653
654 if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
655 !rs_sta->ibss_sta_added) {
656 u8 sta_id = iwl_find_station(priv, hdr->addr1);
657
658 if (sta_id == IWL_INVALID_STATION) {
659 IWL_DEBUG_RATE(priv, "LQ: ADD station %pM\n",
660 hdr->addr1);
661 sta_id = iwl_add_station(priv, hdr->addr1, false,
662 CMD_ASYNC, NULL);
663 }
664 if (sta_id != IWL_INVALID_STATION)
665 rs_sta->ibss_sta_added = 1;
666 }
667
668 spin_lock_irqsave(&rs_sta->lock, flags);
669
670 /* for recent assoc, choose best rate regarding
671 * to rssi value
672 */
673 if (rs_sta->start_rate != IWL_RATE_INVALID) {
674 if (rs_sta->start_rate < index &&
675 (rate_mask & (1 << rs_sta->start_rate)))
676 index = rs_sta->start_rate;
677 rs_sta->start_rate = IWL_RATE_INVALID;
678 }
679
680 /* force user max rate if set by user */
681 if ((max_rate_idx != -1) && (max_rate_idx < index)) {
682 if (rate_mask & (1 << max_rate_idx))
683 index = max_rate_idx;
684 }
685
686 window = &(rs_sta->win[index]);
687
688 fail_count = window->counter - window->success_counter;
689
690 if (((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
691 (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
692 spin_unlock_irqrestore(&rs_sta->lock, flags);
693
694 IWL_DEBUG_RATE(priv, "Invalid average_tpt on rate %d: "
695 "counter: %d, success_counter: %d, "
696 "expected_tpt is %sNULL\n",
697 index,
698 window->counter,
699 window->success_counter,
700 rs_sta->expected_tpt ? "not " : "");
701
702 /* Can't calculate this yet; not enough history */
703 window->average_tpt = IWL_INVALID_VALUE;
704 goto out;
705
706 }
707
708 current_tpt = window->average_tpt;
709
710 high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
711 sband->band);
712 low = high_low & 0xff;
713 high = (high_low >> 8) & 0xff;
714
715 /* If user set max rate, dont allow higher than user constrain */
716 if ((max_rate_idx != -1) && (max_rate_idx < high))
717 high = IWL_RATE_INVALID;
718
719 /* Collect Measured throughputs of adjacent rates */
720 if (low != IWL_RATE_INVALID)
721 low_tpt = rs_sta->win[low].average_tpt;
722
723 if (high != IWL_RATE_INVALID)
724 high_tpt = rs_sta->win[high].average_tpt;
725
726 spin_unlock_irqrestore(&rs_sta->lock, flags);
727
728 scale_action = 0;
729
730 /* Low success ratio , need to drop the rate */
731 if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
732 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
733 scale_action = -1;
734 /* No throughput measured yet for adjacent rates,
735 * try increase */
736 } else if ((low_tpt == IWL_INVALID_VALUE) &&
737 (high_tpt == IWL_INVALID_VALUE)) {
738
739 if (high != IWL_RATE_INVALID && window->success_ratio >= IWL_RATE_INCREASE_TH)
740 scale_action = 1;
741 else if (low != IWL_RATE_INVALID)
742 scale_action = 0;
743
744 /* Both adjacent throughputs are measured, but neither one has
745 * better throughput; we're using the best rate, don't change
746 * it! */
747 } else if ((low_tpt != IWL_INVALID_VALUE) &&
748 (high_tpt != IWL_INVALID_VALUE) &&
749 (low_tpt < current_tpt) && (high_tpt < current_tpt)) {
750
751 IWL_DEBUG_RATE(priv, "No action -- low [%d] & high [%d] < "
752 "current_tpt [%d]\n",
753 low_tpt, high_tpt, current_tpt);
754 scale_action = 0;
755
756 /* At least one of the rates has better throughput */
757 } else {
758 if (high_tpt != IWL_INVALID_VALUE) {
759
760 /* High rate has better throughput, Increase
761 * rate */
762 if (high_tpt > current_tpt &&
763 window->success_ratio >= IWL_RATE_INCREASE_TH)
764 scale_action = 1;
765 else {
766 IWL_DEBUG_RATE(priv,
767 "decrease rate because of high tpt\n");
768 scale_action = 0;
769 }
770 } else if (low_tpt != IWL_INVALID_VALUE) {
771 if (low_tpt > current_tpt) {
772 IWL_DEBUG_RATE(priv,
773 "decrease rate because of low tpt\n");
774 scale_action = -1;
775 } else if (window->success_ratio >= IWL_RATE_INCREASE_TH) {
776 /* Lower rate has better
777 * throughput,decrease rate */
778 scale_action = 1;
779 }
780 }
781 }
782
783 /* Sanity check; asked for decrease, but success rate or throughput
784 * has been good at old rate. Don't change it. */
785 if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
786 ((window->success_ratio > IWL_RATE_HIGH_TH) ||
787 (current_tpt > (100 * rs_sta->expected_tpt[low]))))
788 scale_action = 0;
789
790 switch (scale_action) {
791 case -1:
792
793 /* Decrese rate */
794 if (low != IWL_RATE_INVALID)
795 index = low;
796 break;
797
798 case 1:
799 /* Increase rate */
800 if (high != IWL_RATE_INVALID)
801 index = high;
802
803 break;
804
805 case 0:
806 default:
807 /* No change */
808 break;
809 }
810
811 IWL_DEBUG_RATE(priv, "Selected %d (action %d) - low %d high %d\n",
812 index, scale_action, low, high);
813
814 out:
815
816 rs_sta->last_txrate_idx = index;
817 if (sband->band == IEEE80211_BAND_5GHZ)
818 info->control.rates[0].idx = rs_sta->last_txrate_idx -
819 IWL_FIRST_OFDM_RATE;
820 else
821 info->control.rates[0].idx = rs_sta->last_txrate_idx;
822
823 IWL_DEBUG_RATE(priv, "leave: %d\n", index);
824 }
825
826 #ifdef CONFIG_MAC80211_DEBUGFS
827 static int iwl3945_open_file_generic(struct inode *inode, struct file *file)
828 {
829 file->private_data = inode->i_private;
830 return 0;
831 }
832
833 static ssize_t iwl3945_sta_dbgfs_stats_table_read(struct file *file,
834 char __user *user_buf,
835 size_t count, loff_t *ppos)
836 {
837 char *buff;
838 int desc = 0;
839 int j;
840 ssize_t ret;
841 struct iwl3945_rs_sta *lq_sta = file->private_data;
842
843 buff = kmalloc(1024, GFP_KERNEL);
844 if (!buff)
845 return -ENOMEM;
846
847 desc += sprintf(buff + desc, "tx packets=%d last rate index=%d\n"
848 "rate=0x%X flush time %d\n",
849 lq_sta->tx_packets,
850 lq_sta->last_txrate_idx,
851 lq_sta->start_rate, jiffies_to_msecs(lq_sta->flush_time));
852 for (j = 0; j < IWL_RATE_COUNT_3945; j++) {
853 desc += sprintf(buff+desc,
854 "counter=%d success=%d %%=%d\n",
855 lq_sta->win[j].counter,
856 lq_sta->win[j].success_counter,
857 lq_sta->win[j].success_ratio);
858 }
859 ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
860 kfree(buff);
861 return ret;
862 }
863
864 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
865 .read = iwl3945_sta_dbgfs_stats_table_read,
866 .open = iwl3945_open_file_generic,
867 };
868
869 static void iwl3945_add_debugfs(void *priv, void *priv_sta,
870 struct dentry *dir)
871 {
872 struct iwl3945_rs_sta *lq_sta = priv_sta;
873
874 lq_sta->rs_sta_dbgfs_stats_table_file =
875 debugfs_create_file("rate_stats_table", 0600, dir,
876 lq_sta, &rs_sta_dbgfs_stats_table_ops);
877
878 }
879
880 static void iwl3945_remove_debugfs(void *priv, void *priv_sta)
881 {
882 struct iwl3945_rs_sta *lq_sta = priv_sta;
883 debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
884 }
885 #endif
886
887 static struct rate_control_ops rs_ops = {
888 .module = NULL,
889 .name = RS_NAME,
890 .tx_status = rs_tx_status,
891 .get_rate = rs_get_rate,
892 .rate_init = rs_rate_init,
893 .alloc = rs_alloc,
894 .free = rs_free,
895 .alloc_sta = rs_alloc_sta,
896 .free_sta = rs_free_sta,
897 #ifdef CONFIG_MAC80211_DEBUGFS
898 .add_sta_debugfs = iwl3945_add_debugfs,
899 .remove_sta_debugfs = iwl3945_remove_debugfs,
900 #endif
901
902 };
903
904 void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
905 {
906 struct iwl_priv *priv = hw->priv;
907 s32 rssi = 0;
908 unsigned long flags;
909 struct iwl3945_rs_sta *rs_sta;
910 struct ieee80211_sta *sta;
911 struct iwl3945_sta_priv *psta;
912
913 IWL_DEBUG_RATE(priv, "enter\n");
914
915 rcu_read_lock();
916
917 sta = ieee80211_find_sta(priv->vif,
918 priv->stations[sta_id].sta.sta.addr);
919 if (!sta) {
920 rcu_read_unlock();
921 return;
922 }
923
924 psta = (void *) sta->drv_priv;
925 rs_sta = &psta->rs_sta;
926
927 spin_lock_irqsave(&rs_sta->lock, flags);
928
929 rs_sta->tgg = 0;
930 switch (priv->band) {
931 case IEEE80211_BAND_2GHZ:
932 /* TODO: this always does G, not a regression */
933 if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
934 rs_sta->tgg = 1;
935 rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
936 } else
937 rs_sta->expected_tpt = iwl3945_expected_tpt_g;
938 break;
939
940 case IEEE80211_BAND_5GHZ:
941 rs_sta->expected_tpt = iwl3945_expected_tpt_a;
942 break;
943 case IEEE80211_NUM_BANDS:
944 BUG();
945 break;
946 }
947
948 spin_unlock_irqrestore(&rs_sta->lock, flags);
949
950 rssi = priv->last_rx_rssi;
951 if (rssi == 0)
952 rssi = IWL_MIN_RSSI_VAL;
953
954 IWL_DEBUG_RATE(priv, "Network RSSI: %d\n", rssi);
955
956 rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
957
958 IWL_DEBUG_RATE(priv, "leave: rssi %d assign rate index: "
959 "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
960 iwl3945_rates[rs_sta->start_rate].plcp);
961 rcu_read_unlock();
962 }
963
964 int iwl3945_rate_control_register(void)
965 {
966 return ieee80211_rate_control_register(&rs_ops);
967 }
968
969 void iwl3945_rate_control_unregister(void)
970 {
971 ieee80211_rate_control_unregister(&rs_ops);
972 }
973
974
Linux with added FPC-III support