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 * 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/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 "iwl-3945.h"
40
41 #define RS_NAME "iwl-3945-rs"
42
43 struct iwl3945_rate_scale_data {
44 u64 data;
45 s32 success_counter;
46 s32 success_ratio;
47 s32 counter;
48 s32 average_tpt;
49 unsigned long stamp;
50 };
51
52 struct iwl3945_rs_sta {
53 spinlock_t lock;
54 s32 *expected_tpt;
55 unsigned long last_partial_flush;
56 unsigned long last_flush;
57 u32 flush_time;
58 u32 last_tx_packets;
59 u32 tx_packets;
60 u8 tgg;
61 u8 flush_pending;
62 u8 start_rate;
63 u8 ibss_sta_added;
64 struct timer_list rate_scale_flush;
65 struct iwl3945_rate_scale_data win[IWL_RATE_COUNT];
66 #ifdef CONFIG_MAC80211_DEBUGFS
67 struct dentry *rs_sta_dbgfs_stats_table_file;
68 #endif
69
70 /* used to be in sta_info */
71 int last_txrate_idx;
72 };
73
74 static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT] = {
75 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
76 };
77
78 static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT] = {
79 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
80 };
81
82 static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT] = {
83 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
84 };
85
86 static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT] = {
87 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
88 };
89
90 struct iwl3945_tpt_entry {
91 s8 min_rssi;
92 u8 index;
93 };
94
95 static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
96 {-60, IWL_RATE_54M_INDEX},
97 {-64, IWL_RATE_48M_INDEX},
98 {-72, IWL_RATE_36M_INDEX},
99 {-80, IWL_RATE_24M_INDEX},
100 {-84, IWL_RATE_18M_INDEX},
101 {-85, IWL_RATE_12M_INDEX},
102 {-87, IWL_RATE_9M_INDEX},
103 {-89, IWL_RATE_6M_INDEX}
104 };
105
106 static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
107 {-60, IWL_RATE_54M_INDEX},
108 {-64, IWL_RATE_48M_INDEX},
109 {-68, IWL_RATE_36M_INDEX},
110 {-80, IWL_RATE_24M_INDEX},
111 {-84, IWL_RATE_18M_INDEX},
112 {-85, IWL_RATE_12M_INDEX},
113 {-86, IWL_RATE_11M_INDEX},
114 {-88, IWL_RATE_5M_INDEX},
115 {-90, IWL_RATE_2M_INDEX},
116 {-92, IWL_RATE_1M_INDEX}
117 };
118
119 #define IWL_RATE_MAX_WINDOW 62
120 #define IWL_RATE_FLUSH (3*HZ)
121 #define IWL_RATE_WIN_FLUSH (HZ/2)
122 #define IWL_RATE_HIGH_TH 11520
123 #define IWL_SUCCESS_UP_TH 8960
124 #define IWL_SUCCESS_DOWN_TH 10880
125 #define IWL_RATE_MIN_FAILURE_TH 8
126 #define IWL_RATE_MIN_SUCCESS_TH 8
127 #define IWL_RATE_DECREASE_TH 1920
128
iwl3945_get_rate_index_by_rssi(s32 rssi,enum ieee80211_band band)129 static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, enum ieee80211_band band)
130 {
131 u32 index = 0;
132 u32 table_size = 0;
133 struct iwl3945_tpt_entry *tpt_table = NULL;
134
135 if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
136 rssi = IWL_MIN_RSSI_VAL;
137
138 switch (band) {
139 case IEEE80211_BAND_2GHZ:
140 tpt_table = iwl3945_tpt_table_g;
141 table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
142 break;
143
144 case IEEE80211_BAND_5GHZ:
145 tpt_table = iwl3945_tpt_table_a;
146 table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
147 break;
148
149 default:
150 BUG();
151 break;
152 }
153
154 while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
155 index++;
156
157 index = min(index, (table_size - 1));
158
159 return tpt_table[index].index;
160 }
161
iwl3945_clear_window(struct iwl3945_rate_scale_data * window)162 static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
163 {
164 window->data = 0;
165 window->success_counter = 0;
166 window->success_ratio = -1;
167 window->counter = 0;
168 window->average_tpt = IWL_INV_TPT;
169 window->stamp = 0;
170 }
171
172 /**
173 * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
174 *
175 * Returns the number of windows that have gathered data but were
176 * not flushed. If there were any that were not flushed, then
177 * reschedule the rate flushing routine.
178 */
iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta * rs_sta)179 static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
180 {
181 int unflushed = 0;
182 int i;
183 unsigned long flags;
184
185 /*
186 * For each rate, if we have collected data on that rate
187 * and it has been more than IWL_RATE_WIN_FLUSH
188 * since we flushed, clear out the gathered statistics
189 */
190 for (i = 0; i < IWL_RATE_COUNT; i++) {
191 if (!rs_sta->win[i].counter)
192 continue;
193
194 spin_lock_irqsave(&rs_sta->lock, flags);
195 if (time_after(jiffies, rs_sta->win[i].stamp +
196 IWL_RATE_WIN_FLUSH)) {
197 IWL_DEBUG_RATE("flushing %d samples of rate "
198 "index %d\n",
199 rs_sta->win[i].counter, i);
200 iwl3945_clear_window(&rs_sta->win[i]);
201 } else
202 unflushed++;
203 spin_unlock_irqrestore(&rs_sta->lock, flags);
204 }
205
206 return unflushed;
207 }
208
209 #define IWL_RATE_FLUSH_MAX 5000 /* msec */
210 #define IWL_RATE_FLUSH_MIN 50 /* msec */
211 #define IWL_AVERAGE_PACKETS 1500
212
iwl3945_bg_rate_scale_flush(unsigned long data)213 static void iwl3945_bg_rate_scale_flush(unsigned long data)
214 {
215 struct iwl3945_rs_sta *rs_sta = (void *)data;
216 int unflushed = 0;
217 unsigned long flags;
218 u32 packet_count, duration, pps;
219
220 IWL_DEBUG_RATE("enter\n");
221
222 unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
223
224 spin_lock_irqsave(&rs_sta->lock, flags);
225
226 /* Number of packets Rx'd since last time this timer ran */
227 packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
228
229 rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
230
231 if (unflushed) {
232 duration =
233 jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
234
235 IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
236 packet_count, duration);
237
238 /* Determine packets per second */
239 if (duration)
240 pps = (packet_count * 1000) / duration;
241 else
242 pps = 0;
243
244 if (pps) {
245 duration = (IWL_AVERAGE_PACKETS * 1000) / pps;
246 if (duration < IWL_RATE_FLUSH_MIN)
247 duration = IWL_RATE_FLUSH_MIN;
248 else if (duration > IWL_RATE_FLUSH_MAX)
249 duration = IWL_RATE_FLUSH_MAX;
250 } else
251 duration = IWL_RATE_FLUSH_MAX;
252
253 rs_sta->flush_time = msecs_to_jiffies(duration);
254
255 IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
256 duration, packet_count);
257
258 mod_timer(&rs_sta->rate_scale_flush, jiffies +
259 rs_sta->flush_time);
260
261 rs_sta->last_partial_flush = jiffies;
262 } else {
263 rs_sta->flush_time = IWL_RATE_FLUSH;
264 rs_sta->flush_pending = 0;
265 }
266 /* If there weren't any unflushed entries, we don't schedule the timer
267 * to run again */
268
269 rs_sta->last_flush = jiffies;
270
271 spin_unlock_irqrestore(&rs_sta->lock, flags);
272
273 IWL_DEBUG_RATE("leave\n");
274 }
275
276 /**
277 * iwl3945_collect_tx_data - Update the success/failure sliding window
278 *
279 * We keep a sliding window of the last 64 packets transmitted
280 * at this rate. window->data contains the bitmask of successful
281 * packets.
282 */
iwl3945_collect_tx_data(struct iwl3945_rs_sta * rs_sta,struct iwl3945_rate_scale_data * window,int success,int retries,int index)283 static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
284 struct iwl3945_rate_scale_data *window,
285 int success, int retries, int index)
286 {
287 unsigned long flags;
288 s32 fail_count;
289
290 if (!retries) {
291 IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
292 return;
293 }
294
295 spin_lock_irqsave(&rs_sta->lock, flags);
296 while (retries--) {
297
298 /* If we have filled up the window then subtract one from the
299 * success counter if the high-bit is counting toward
300 * success */
301 if (window->counter == IWL_RATE_MAX_WINDOW) {
302 if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
303 window->success_counter--;
304 } else
305 window->counter++;
306
307 /* Slide the window to the left one bit */
308 window->data = (window->data << 1);
309
310 /* If this packet was a success then set the low bit high */
311 if (success) {
312 window->success_counter++;
313 window->data |= 1;
314 }
315
316 /* window->counter can't be 0 -- it is either >0 or
317 * IWL_RATE_MAX_WINDOW */
318 window->success_ratio = 12800 * window->success_counter /
319 window->counter;
320
321 /* Tag this window as having been updated */
322 window->stamp = jiffies;
323
324 }
325
326 fail_count = window->counter - window->success_counter;
327 if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
328 (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
329 window->average_tpt = ((window->success_ratio *
330 rs_sta->expected_tpt[index] + 64) / 128);
331 else
332 window->average_tpt = IWL_INV_TPT;
333
334 spin_unlock_irqrestore(&rs_sta->lock, flags);
335
336 }
337
rs_rate_init(void * priv_r,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,void * priv_sta)338 static void rs_rate_init(void *priv_r, struct ieee80211_supported_band *sband,
339 struct ieee80211_sta *sta, void *priv_sta)
340 {
341 struct iwl3945_rs_sta *rs_sta = priv_sta;
342 struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_r;
343 int i;
344
345 IWL_DEBUG_RATE("enter\n");
346
347 /* TODO: what is a good starting rate for STA? About middle? Maybe not
348 * the lowest or the highest rate.. Could consider using RSSI from
349 * previous packets? Need to have IEEE 802.1X auth succeed immediately
350 * after assoc.. */
351
352 for (i = sband->n_bitrates - 1; i >= 0; i--) {
353 if (sta->supp_rates[sband->band] & (1 << i)) {
354 rs_sta->last_txrate_idx = i;
355 break;
356 }
357 }
358
359 priv->sta_supp_rates = sta->supp_rates[sband->band];
360 /* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
361 if (sband->band == IEEE80211_BAND_5GHZ) {
362 rs_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
363 priv->sta_supp_rates = priv->sta_supp_rates <<
364 IWL_FIRST_OFDM_RATE;
365 }
366
367
368 IWL_DEBUG_RATE("leave\n");
369 }
370
rs_alloc(struct ieee80211_hw * hw,struct dentry * debugfsdir)371 static void *rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
372 {
373 return hw->priv;
374 }
375
376 /* rate scale requires free function to be implemented */
rs_free(void * priv)377 static void rs_free(void *priv)
378 {
379 return;
380 }
381
rs_alloc_sta(void * priv,struct ieee80211_sta * sta,gfp_t gfp)382 static void *rs_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
383 {
384 struct iwl3945_rs_sta *rs_sta;
385 struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
386 int i;
387
388 /*
389 * XXX: If it's using sta->drv_priv anyway, it might
390 * as well just put all the information there.
391 */
392
393 IWL_DEBUG_RATE("enter\n");
394
395 rs_sta = kzalloc(sizeof(struct iwl3945_rs_sta), gfp);
396 if (!rs_sta) {
397 IWL_DEBUG_RATE("leave: ENOMEM\n");
398 return NULL;
399 }
400
401 psta->rs_sta = rs_sta;
402
403 spin_lock_init(&rs_sta->lock);
404
405 rs_sta->start_rate = IWL_RATE_INVALID;
406
407 /* default to just 802.11b */
408 rs_sta->expected_tpt = iwl3945_expected_tpt_b;
409
410 rs_sta->last_partial_flush = jiffies;
411 rs_sta->last_flush = jiffies;
412 rs_sta->flush_time = IWL_RATE_FLUSH;
413 rs_sta->last_tx_packets = 0;
414 rs_sta->ibss_sta_added = 0;
415
416 init_timer(&rs_sta->rate_scale_flush);
417 rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
418 rs_sta->rate_scale_flush.function = &iwl3945_bg_rate_scale_flush;
419
420 for (i = 0; i < IWL_RATE_COUNT; i++)
421 iwl3945_clear_window(&rs_sta->win[i]);
422
423 IWL_DEBUG_RATE("leave\n");
424
425 return rs_sta;
426 }
427
rs_free_sta(void * priv,struct ieee80211_sta * sta,void * priv_sta)428 static void rs_free_sta(void *priv, struct ieee80211_sta *sta,
429 void *priv_sta)
430 {
431 struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
432 struct iwl3945_rs_sta *rs_sta = priv_sta;
433
434 psta->rs_sta = NULL;
435
436 IWL_DEBUG_RATE("enter\n");
437 del_timer_sync(&rs_sta->rate_scale_flush);
438 kfree(rs_sta);
439 IWL_DEBUG_RATE("leave\n");
440 }
441
442
443 /**
444 * rs_tx_status - Update rate control values based on Tx results
445 *
446 * NOTE: Uses iwl3945_priv->retry_rate for the # of retries attempted by
447 * the hardware for each rate.
448 */
rs_tx_status(void * priv_rate,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,void * priv_sta,struct sk_buff * skb)449 static void rs_tx_status(void *priv_rate, struct ieee80211_supported_band *sband,
450 struct ieee80211_sta *sta, void *priv_sta,
451 struct sk_buff *skb)
452 {
453 s8 retries = 0, current_count;
454 int scale_rate_index, first_index, last_index;
455 unsigned long flags;
456 struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
457 struct iwl3945_rs_sta *rs_sta = priv_sta;
458 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
459
460 IWL_DEBUG_RATE("enter\n");
461
462 retries = info->status.rates[0].count;
463
464 first_index = sband->bitrates[info->status.rates[0].idx].hw_value;
465 if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
466 IWL_DEBUG_RATE("leave: Rate out of bounds: %d\n", first_index);
467 return;
468 }
469
470 if (!priv_sta) {
471 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
472 return;
473 }
474
475 rs_sta->tx_packets++;
476
477 scale_rate_index = first_index;
478 last_index = first_index;
479
480 /*
481 * Update the window for each rate. We determine which rates
482 * were Tx'd based on the total number of retries vs. the number
483 * of retries configured for each rate -- currently set to the
484 * priv value 'retry_rate' vs. rate specific
485 *
486 * On exit from this while loop last_index indicates the rate
487 * at which the frame was finally transmitted (or failed if no
488 * ACK)
489 */
490 while (retries > 1) {
491 if ((retries - 1) < priv->retry_rate) {
492 current_count = (retries - 1);
493 last_index = scale_rate_index;
494 } else {
495 current_count = priv->retry_rate;
496 last_index = iwl3945_rs_next_rate(priv,
497 scale_rate_index);
498 }
499
500 /* Update this rate accounting for as many retries
501 * as was used for it (per current_count) */
502 iwl3945_collect_tx_data(rs_sta,
503 &rs_sta->win[scale_rate_index],
504 0, current_count, scale_rate_index);
505 IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
506 scale_rate_index, current_count);
507
508 retries -= current_count;
509
510 scale_rate_index = last_index;
511 }
512
513
514 /* Update the last index window with success/failure based on ACK */
515 IWL_DEBUG_RATE("Update rate %d with %s.\n",
516 last_index,
517 (info->flags & IEEE80211_TX_STAT_ACK) ?
518 "success" : "failure");
519 iwl3945_collect_tx_data(rs_sta,
520 &rs_sta->win[last_index],
521 info->flags & IEEE80211_TX_STAT_ACK, 1, last_index);
522
523 /* We updated the rate scale window -- if its been more than
524 * flush_time since the last run, schedule the flush
525 * again */
526 spin_lock_irqsave(&rs_sta->lock, flags);
527
528 if (!rs_sta->flush_pending &&
529 time_after(jiffies, rs_sta->last_flush +
530 rs_sta->flush_time)) {
531
532 rs_sta->last_partial_flush = jiffies;
533 rs_sta->flush_pending = 1;
534 mod_timer(&rs_sta->rate_scale_flush,
535 jiffies + rs_sta->flush_time);
536 }
537
538 spin_unlock_irqrestore(&rs_sta->lock, flags);
539
540 IWL_DEBUG_RATE("leave\n");
541
542 return;
543 }
544
iwl3945_get_adjacent_rate(struct iwl3945_rs_sta * rs_sta,u8 index,u16 rate_mask,enum ieee80211_band band)545 static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
546 u8 index, u16 rate_mask, enum ieee80211_band band)
547 {
548 u8 high = IWL_RATE_INVALID;
549 u8 low = IWL_RATE_INVALID;
550
551 /* 802.11A walks to the next literal adjacent rate in
552 * the rate table */
553 if (unlikely(band == IEEE80211_BAND_5GHZ)) {
554 int i;
555 u32 mask;
556
557 /* Find the previous rate that is in the rate mask */
558 i = index - 1;
559 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
560 if (rate_mask & mask) {
561 low = i;
562 break;
563 }
564 }
565
566 /* Find the next rate that is in the rate mask */
567 i = index + 1;
568 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
569 if (rate_mask & mask) {
570 high = i;
571 break;
572 }
573 }
574
575 return (high << 8) | low;
576 }
577
578 low = index;
579 while (low != IWL_RATE_INVALID) {
580 if (rs_sta->tgg)
581 low = iwl3945_rates[low].prev_rs_tgg;
582 else
583 low = iwl3945_rates[low].prev_rs;
584 if (low == IWL_RATE_INVALID)
585 break;
586 if (rate_mask & (1 << low))
587 break;
588 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
589 }
590
591 high = index;
592 while (high != IWL_RATE_INVALID) {
593 if (rs_sta->tgg)
594 high = iwl3945_rates[high].next_rs_tgg;
595 else
596 high = iwl3945_rates[high].next_rs;
597 if (high == IWL_RATE_INVALID)
598 break;
599 if (rate_mask & (1 << high))
600 break;
601 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
602 }
603
604 return (high << 8) | low;
605 }
606
607 /**
608 * rs_get_rate - find the rate for the requested packet
609 *
610 * Returns the ieee80211_rate structure allocated by the driver.
611 *
612 * The rate control algorithm has no internal mapping between hw_mode's
613 * rate ordering and the rate ordering used by the rate control algorithm.
614 *
615 * The rate control algorithm uses a single table of rates that goes across
616 * the entire A/B/G spectrum vs. being limited to just one particular
617 * hw_mode.
618 *
619 * As such, we can't convert the index obtained below into the hw_mode's
620 * rate table and must reference the driver allocated rate table
621 *
622 */
rs_get_rate(void * priv_r,struct ieee80211_sta * sta,void * priv_sta,struct ieee80211_tx_rate_control * txrc)623 static void rs_get_rate(void *priv_r, struct ieee80211_sta *sta,
624 void *priv_sta, struct ieee80211_tx_rate_control *txrc)
625 {
626 struct ieee80211_supported_band *sband = txrc->sband;
627 struct sk_buff *skb = txrc->skb;
628 u8 low = IWL_RATE_INVALID;
629 u8 high = IWL_RATE_INVALID;
630 u16 high_low;
631 int index;
632 struct iwl3945_rs_sta *rs_sta = priv_sta;
633 struct iwl3945_rate_scale_data *window = NULL;
634 int current_tpt = IWL_INV_TPT;
635 int low_tpt = IWL_INV_TPT;
636 int high_tpt = IWL_INV_TPT;
637 u32 fail_count;
638 s8 scale_action = 0;
639 unsigned long flags;
640 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
641 u16 fc;
642 u16 rate_mask = 0;
643 struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_r;
644 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
645
646 IWL_DEBUG_RATE("enter\n");
647
648 if (sta)
649 rate_mask = sta->supp_rates[sband->band];
650
651 /* Send management frames and broadcast/multicast data using lowest
652 * rate. */
653 fc = le16_to_cpu(hdr->frame_control);
654 if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
655 is_multicast_ether_addr(hdr->addr1) ||
656 !sta || !priv_sta) {
657 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
658 if (!rate_mask)
659 info->control.rates[0].idx =
660 rate_lowest_index(sband, NULL);
661 else
662 info->control.rates[0].idx =
663 rate_lowest_index(sband, sta);
664 return;
665 }
666
667 index = min(rs_sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT - 1);
668
669 if (sband->band == IEEE80211_BAND_5GHZ)
670 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
671
672 if ((priv->iw_mode == NL80211_IFTYPE_ADHOC) &&
673 !rs_sta->ibss_sta_added) {
674 u8 sta_id = iwl3945_hw_find_station(priv, hdr->addr1);
675
676 if (sta_id == IWL_INVALID_STATION) {
677 IWL_DEBUG_RATE("LQ: ADD station %pm\n",
678 hdr->addr1);
679 sta_id = iwl3945_add_station(priv,
680 hdr->addr1, 0, CMD_ASYNC);
681 }
682 if (sta_id != IWL_INVALID_STATION)
683 rs_sta->ibss_sta_added = 1;
684 }
685
686 spin_lock_irqsave(&rs_sta->lock, flags);
687
688 /* for recent assoc, choose best rate regarding
689 * to rssi value
690 */
691 if (rs_sta->start_rate != IWL_RATE_INVALID) {
692 if (rs_sta->start_rate < index &&
693 (rate_mask & (1 << rs_sta->start_rate)))
694 index = rs_sta->start_rate;
695 rs_sta->start_rate = IWL_RATE_INVALID;
696 }
697
698 window = &(rs_sta->win[index]);
699
700 fail_count = window->counter - window->success_counter;
701
702 if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
703 (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
704 spin_unlock_irqrestore(&rs_sta->lock, flags);
705
706 IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
707 "counter: %d, success_counter: %d, "
708 "expected_tpt is %sNULL\n",
709 index,
710 window->counter,
711 window->success_counter,
712 rs_sta->expected_tpt ? "not " : "");
713 goto out;
714
715 }
716
717 current_tpt = window->average_tpt;
718
719 high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
720 sband->band);
721 low = high_low & 0xff;
722 high = (high_low >> 8) & 0xff;
723
724 if (low != IWL_RATE_INVALID)
725 low_tpt = rs_sta->win[low].average_tpt;
726
727 if (high != IWL_RATE_INVALID)
728 high_tpt = rs_sta->win[high].average_tpt;
729
730 spin_unlock_irqrestore(&rs_sta->lock, flags);
731
732 scale_action = 1;
733
734 if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
735 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
736 scale_action = -1;
737 } else if ((low_tpt == IWL_INV_TPT) && (high_tpt == IWL_INV_TPT))
738 scale_action = 1;
739 else if ((low_tpt != IWL_INV_TPT) && (high_tpt != IWL_INV_TPT) &&
740 (low_tpt < current_tpt) && (high_tpt < current_tpt)) {
741 IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
742 "current_tpt [%d]\n",
743 low_tpt, high_tpt, current_tpt);
744 scale_action = 0;
745 } else {
746 if (high_tpt != IWL_INV_TPT) {
747 if (high_tpt > current_tpt)
748 scale_action = 1;
749 else {
750 IWL_DEBUG_RATE
751 ("decrease rate because of high tpt\n");
752 scale_action = -1;
753 }
754 } else if (low_tpt != IWL_INV_TPT) {
755 if (low_tpt > current_tpt) {
756 IWL_DEBUG_RATE
757 ("decrease rate because of low tpt\n");
758 scale_action = -1;
759 } else
760 scale_action = 1;
761 }
762 }
763
764 if (scale_action == -1) {
765 if (window->success_ratio > IWL_SUCCESS_DOWN_TH)
766 scale_action = 0;
767 } else if (scale_action == 1) {
768 if (window->success_ratio < IWL_SUCCESS_UP_TH) {
769 IWL_DEBUG_RATE("No action -- success_ratio [%d] < "
770 "SUCCESS UP\n", window->success_ratio);
771 scale_action = 0;
772 }
773 }
774
775 switch (scale_action) {
776 case -1:
777 if (low != IWL_RATE_INVALID)
778 index = low;
779 break;
780
781 case 1:
782 if (high != IWL_RATE_INVALID)
783 index = high;
784
785 break;
786
787 case 0:
788 default:
789 break;
790 }
791
792 IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
793 index, scale_action, low, high);
794
795 out:
796
797 rs_sta->last_txrate_idx = index;
798 if (sband->band == IEEE80211_BAND_5GHZ)
799 info->control.rates[0].idx = rs_sta->last_txrate_idx -
800 IWL_FIRST_OFDM_RATE;
801 else
802 info->control.rates[0].idx = rs_sta->last_txrate_idx;
803
804 IWL_DEBUG_RATE("leave: %d\n", index);
805 }
806
807 #ifdef CONFIG_MAC80211_DEBUGFS
iwl3945_open_file_generic(struct inode * inode,struct file * file)808 static int iwl3945_open_file_generic(struct inode *inode, struct file *file)
809 {
810 file->private_data = inode->i_private;
811 return 0;
812 }
813
iwl3945_sta_dbgfs_stats_table_read(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)814 static ssize_t iwl3945_sta_dbgfs_stats_table_read(struct file *file,
815 char __user *user_buf,
816 size_t count, loff_t *ppos)
817 {
818 char buff[1024];
819 int desc = 0;
820 int j;
821 struct iwl3945_rs_sta *lq_sta = file->private_data;
822
823 desc += sprintf(buff + desc, "tx packets=%d last rate index=%d\n"
824 "rate=0x%X flush time %d\n",
825 lq_sta->tx_packets,
826 lq_sta->last_txrate_idx,
827 lq_sta->start_rate, jiffies_to_msecs(lq_sta->flush_time));
828 for (j = 0; j < IWL_RATE_COUNT; j++) {
829 desc += sprintf(buff+desc,
830 "counter=%d success=%d %%=%d\n",
831 lq_sta->win[j].counter,
832 lq_sta->win[j].success_counter,
833 lq_sta->win[j].success_ratio);
834 }
835 return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
836 }
837
838 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
839 .read = iwl3945_sta_dbgfs_stats_table_read,
840 .open = iwl3945_open_file_generic,
841 };
842
iwl3945_add_debugfs(void * priv,void * priv_sta,struct dentry * dir)843 static void iwl3945_add_debugfs(void *priv, void *priv_sta,
844 struct dentry *dir)
845 {
846 struct iwl3945_rs_sta *lq_sta = priv_sta;
847
848 lq_sta->rs_sta_dbgfs_stats_table_file =
849 debugfs_create_file("rate_stats_table", 0600, dir,
850 lq_sta, &rs_sta_dbgfs_stats_table_ops);
851
852 }
853
iwl3945_remove_debugfs(void * priv,void * priv_sta)854 static void iwl3945_remove_debugfs(void *priv, void *priv_sta)
855 {
856 struct iwl3945_rs_sta *lq_sta = priv_sta;
857 debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
858 }
859 #endif
860
861 static struct rate_control_ops rs_ops = {
862 .module = NULL,
863 .name = RS_NAME,
864 .tx_status = rs_tx_status,
865 .get_rate = rs_get_rate,
866 .rate_init = rs_rate_init,
867 .alloc = rs_alloc,
868 .free = rs_free,
869 .alloc_sta = rs_alloc_sta,
870 .free_sta = rs_free_sta,
871 #ifdef CONFIG_MAC80211_DEBUGFS
872 .add_sta_debugfs = iwl3945_add_debugfs,
873 .remove_sta_debugfs = iwl3945_remove_debugfs,
874 #endif
875
876 };
877
iwl3945_rate_scale_init(struct ieee80211_hw * hw,s32 sta_id)878 void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
879 {
880 struct iwl3945_priv *priv = hw->priv;
881 s32 rssi = 0;
882 unsigned long flags;
883 struct iwl3945_rs_sta *rs_sta;
884 struct ieee80211_sta *sta;
885 struct iwl3945_sta_priv *psta;
886
887 IWL_DEBUG_RATE("enter\n");
888
889 rcu_read_lock();
890
891 sta = ieee80211_find_sta(hw, priv->stations[sta_id].sta.sta.addr);
892 if (!sta) {
893 rcu_read_unlock();
894 return;
895 }
896
897 psta = (void *) sta->drv_priv;
898 rs_sta = psta->rs_sta;
899
900 spin_lock_irqsave(&rs_sta->lock, flags);
901
902 rs_sta->tgg = 0;
903 switch (priv->band) {
904 case IEEE80211_BAND_2GHZ:
905 /* TODO: this always does G, not a regression */
906 if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
907 rs_sta->tgg = 1;
908 rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
909 } else
910 rs_sta->expected_tpt = iwl3945_expected_tpt_g;
911 break;
912
913 case IEEE80211_BAND_5GHZ:
914 rs_sta->expected_tpt = iwl3945_expected_tpt_a;
915 break;
916 case IEEE80211_NUM_BANDS:
917 BUG();
918 break;
919 }
920
921 spin_unlock_irqrestore(&rs_sta->lock, flags);
922
923 rssi = priv->last_rx_rssi;
924 if (rssi == 0)
925 rssi = IWL_MIN_RSSI_VAL;
926
927 IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
928
929 rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
930
931 IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
932 "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
933 iwl3945_rates[rs_sta->start_rate].plcp);
934 rcu_read_unlock();
935 }
936
iwl3945_rate_control_register(void)937 int iwl3945_rate_control_register(void)
938 {
939 return ieee80211_rate_control_register(&rs_ops);
940 }
941
iwl3945_rate_control_unregister(void)942 void iwl3945_rate_control_unregister(void)
943 {
944 ieee80211_rate_control_unregister(&rs_ops);
945 }
946
947
948