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iwlegacy: remove wireless extensions inclusions
[deliverable/linux.git] / drivers / net / wireless / iwlegacy / iwl-3945-rs.c
CommitLineData
4bc85c13
WYG		 1/******************************************************************************
2 *
be663ab6 3 * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved.
4bc85c13
WYG		 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>
4bc85c13
WYG		 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-commands.h"
40#include "iwl-3945.h"
41#include "iwl-sta.h"
42
43#define RS_NAME "iwl-3945-rs"
44
45static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT_3945] = {
46 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
47};
48
49static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT_3945] = {
50 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
51};
52
53static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT_3945] = {
54 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
55};
56
57static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT_3945] = {
58 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
59};
60
61struct iwl3945_tpt_entry {
62 s8 min_rssi;
63 u8 index;
64};
65
66static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
67 {-60, IWL_RATE_54M_INDEX},
68 {-64, IWL_RATE_48M_INDEX},
69 {-72, IWL_RATE_36M_INDEX},
70 {-80, IWL_RATE_24M_INDEX},
71 {-84, IWL_RATE_18M_INDEX},
72 {-85, IWL_RATE_12M_INDEX},
73 {-87, IWL_RATE_9M_INDEX},
74 {-89, IWL_RATE_6M_INDEX}
75};
76
77static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
78 {-60, IWL_RATE_54M_INDEX},
79 {-64, IWL_RATE_48M_INDEX},
80 {-68, IWL_RATE_36M_INDEX},
81 {-80, IWL_RATE_24M_INDEX},
82 {-84, IWL_RATE_18M_INDEX},
83 {-85, IWL_RATE_12M_INDEX},
84 {-86, IWL_RATE_11M_INDEX},
85 {-88, IWL_RATE_5M_INDEX},
86 {-90, IWL_RATE_2M_INDEX},
87 {-92, IWL_RATE_1M_INDEX}
88};
89
90#define IWL_RATE_MAX_WINDOW 62
be663ab6 91#define IWL_RATE_FLUSH (3*HZ)
4bc85c13
WYG		 92#define IWL_RATE_WIN_FLUSH (HZ/2)
93#define IWL39_RATE_HIGH_TH 11520
94#define IWL_SUCCESS_UP_TH 8960
95#define IWL_SUCCESS_DOWN_TH 10880
96#define IWL_RATE_MIN_FAILURE_TH 6
97#define IWL_RATE_MIN_SUCCESS_TH 8
98#define IWL_RATE_DECREASE_TH 1920
99#define IWL_RATE_RETRY_TH 15
100
101static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, enum ieee80211_band band)
102{
103 u32 index = 0;
104 u32 table_size = 0;
105 struct iwl3945_tpt_entry *tpt_table = NULL;
106
107 if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
108 rssi = IWL_MIN_RSSI_VAL;
109
110 switch (band) {
111 case IEEE80211_BAND_2GHZ:
112 tpt_table = iwl3945_tpt_table_g;
113 table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
114 break;
115
116 case IEEE80211_BAND_5GHZ:
117 tpt_table = iwl3945_tpt_table_a;
118 table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
119 break;
120
121 default:
122 BUG();
123 break;
124 }
125
126 while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
127 index++;
128
129 index = min(index, (table_size - 1));
130
131 return tpt_table[index].index;
132}
133
134static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
135{
136 window->data = 0;
137 window->success_counter = 0;
138 window->success_ratio = -1;
139 window->counter = 0;
140 window->average_tpt = IWL_INVALID_VALUE;
141 window->stamp = 0;
142}
143
144/**
145 * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
146 *
147 * Returns the number of windows that have gathered data but were
148 * not flushed. If there were any that were not flushed, then
149 * reschedule the rate flushing routine.
150 */
151static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
152{
153 int unflushed = 0;
154 int i;
155 unsigned long flags;
156 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
157
158 /*
159 * For each rate, if we have collected data on that rate
160 * and it has been more than IWL_RATE_WIN_FLUSH
161 * since we flushed, clear out the gathered statistics
162 */
163 for (i = 0; i < IWL_RATE_COUNT_3945; i++) {
164 if (!rs_sta->win[i].counter)
165 continue;
166
167 spin_lock_irqsave(&rs_sta->lock, flags);
168 if (time_after(jiffies, rs_sta->win[i].stamp +
169 IWL_RATE_WIN_FLUSH)) {
170 IWL_DEBUG_RATE(priv, "flushing %d samples of rate "
171 "index %d\n",
172 rs_sta->win[i].counter, i);
173 iwl3945_clear_window(&rs_sta->win[i]);
174 } else
175 unflushed++;
176 spin_unlock_irqrestore(&rs_sta->lock, flags);
177 }
178
179 return unflushed;
180}
181
182#define IWL_RATE_FLUSH_MAX 5000 /* msec */
183#define IWL_RATE_FLUSH_MIN 50 /* msec */
184#define IWL_AVERAGE_PACKETS 1500
185
186static void iwl3945_bg_rate_scale_flush(unsigned long data)
187{
188 struct iwl3945_rs_sta *rs_sta = (void *)data;
189 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
190 int unflushed = 0;
191 unsigned long flags;
192 u32 packet_count, duration, pps;
193
194 IWL_DEBUG_RATE(priv, "enter\n");
195
196 unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
197
198 spin_lock_irqsave(&rs_sta->lock, flags);
199
200 /* Number of packets Rx'd since last time this timer ran */
201 packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
202
203 rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
204
205 if (unflushed) {
206 duration =
207 jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
208
209 IWL_DEBUG_RATE(priv, "Tx'd %d packets in %dms\n",
210 packet_count, duration);
211
212 /* Determine packets per second */
213 if (duration)
214 pps = (packet_count * 1000) / duration;
215 else
216 pps = 0;
217
218 if (pps) {
219 duration = (IWL_AVERAGE_PACKETS * 1000) / pps;
220 if (duration < IWL_RATE_FLUSH_MIN)
221 duration = IWL_RATE_FLUSH_MIN;
222 else if (duration > IWL_RATE_FLUSH_MAX)
223 duration = IWL_RATE_FLUSH_MAX;
224 } else
225 duration = IWL_RATE_FLUSH_MAX;
226
227 rs_sta->flush_time = msecs_to_jiffies(duration);
228
229 IWL_DEBUG_RATE(priv, "new flush period: %d msec ave %d\n",
230 duration, packet_count);
231
232 mod_timer(&rs_sta->rate_scale_flush, jiffies +
233 rs_sta->flush_time);
234
235 rs_sta->last_partial_flush = jiffies;
236 } else {
237 rs_sta->flush_time = IWL_RATE_FLUSH;
238 rs_sta->flush_pending = 0;
239 }
240 /* If there weren't any unflushed entries, we don't schedule the timer
241 * to run again */
242
243 rs_sta->last_flush = jiffies;
244
245 spin_unlock_irqrestore(&rs_sta->lock, flags);
246
247 IWL_DEBUG_RATE(priv, "leave\n");
248}
249
250/**
251 * iwl3945_collect_tx_data - Update the success/failure sliding window
252 *
253 * We keep a sliding window of the last 64 packets transmitted
254 * at this rate. window->data contains the bitmask of successful
255 * packets.
256 */
257static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
258 struct iwl3945_rate_scale_data *window,
259 int success, int retries, int index)
260{
261 unsigned long flags;
262 s32 fail_count;
263 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
264
265 if (!retries) {
266 IWL_DEBUG_RATE(priv, "leave: retries == 0 -- should be at least 1\n");
267 return;
268 }
269
270 spin_lock_irqsave(&rs_sta->lock, flags);
271
272 /*
273 * Keep track of only the latest 62 tx frame attempts in this rate's
274 * history window; anything older isn't really relevant any more.
275 * If we have filled up the sliding window, drop the oldest attempt;
276 * if the oldest attempt (highest bit in bitmap) shows "success",
277 * subtract "1" from the success counter (this is the main reason
278 * we keep these bitmaps!).
279 * */
280 while (retries > 0) {
281 if (window->counter >= IWL_RATE_MAX_WINDOW) {
282
283 /* remove earliest */
284 window->counter = IWL_RATE_MAX_WINDOW - 1;
285
286 if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1))) {
287 window->data &= ~(1ULL << (IWL_RATE_MAX_WINDOW - 1));
288 window->success_counter--;
289 }
290 }
291
292 /* Increment frames-attempted counter */
293 window->counter++;
294
295 /* Shift bitmap by one frame (throw away oldest history),
296 * OR in "1", and increment "success" if this
297 * frame was successful. */
298 window->data <<= 1;
299 if (success > 0) {
300 window->success_counter++;
301 window->data |= 0x1;
302 success--;
303 }
304
305 retries--;
306 }
307
308 /* Calculate current success ratio, avoid divide-by-0! */
309 if (window->counter > 0)
310 window->success_ratio = 128 * (100 * window->success_counter)
311 / window->counter;
312 else
313 window->success_ratio = IWL_INVALID_VALUE;
314
315 fail_count = window->counter - window->success_counter;
316
317 /* Calculate average throughput, if we have enough history. */
318 if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
319 (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
320 window->average_tpt = ((window->success_ratio *
321 rs_sta->expected_tpt[index] + 64) / 128);
322 else
323 window->average_tpt = IWL_INVALID_VALUE;
324
325 /* Tag this window as having been updated */
326 window->stamp = jiffies;
327
328 spin_unlock_irqrestore(&rs_sta->lock, flags);
329
330}
331
332/*
333 * Called after adding a new station to initialize rate scaling
334 */
335void iwl3945_rs_rate_init(struct iwl_priv *priv, struct ieee80211_sta *sta, u8 sta_id)
336{
337 struct ieee80211_hw *hw = priv->hw;
338 struct ieee80211_conf *conf = &priv->hw->conf;
339 struct iwl3945_sta_priv *psta;
340 struct iwl3945_rs_sta *rs_sta;
341 struct ieee80211_supported_band *sband;
342 int i;
343
344 IWL_DEBUG_INFO(priv, "enter\n");
345 if (sta_id == priv->contexts[IWL_RXON_CTX_BSS].bcast_sta_id)
346 goto out;
347
348 psta = (struct iwl3945_sta_priv *) sta->drv_priv;
349 rs_sta = &psta->rs_sta;
350 sband = hw->wiphy->bands[conf->channel->band];
351
352 rs_sta->priv = priv;
353
354 rs_sta->start_rate = IWL_RATE_INVALID;
355
356 /* default to just 802.11b */
357 rs_sta->expected_tpt = iwl3945_expected_tpt_b;
358
359 rs_sta->last_partial_flush = jiffies;
360 rs_sta->last_flush = jiffies;
361 rs_sta->flush_time = IWL_RATE_FLUSH;
362 rs_sta->last_tx_packets = 0;
363
364 rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
365 rs_sta->rate_scale_flush.function = iwl3945_bg_rate_scale_flush;
366
367 for (i = 0; i < IWL_RATE_COUNT_3945; i++)
368 iwl3945_clear_window(&rs_sta->win[i]);
369
370 /* TODO: what is a good starting rate for STA? About middle? Maybe not
371 * the lowest or the highest rate.. Could consider using RSSI from
372 * previous packets? Need to have IEEE 802.1X auth succeed immediately
373 * after assoc.. */
374
375 for (i = sband->n_bitrates - 1; i >= 0; i--) {
376 if (sta->supp_rates[sband->band] & (1 << i)) {
377 rs_sta->last_txrate_idx = i;
378 break;
379 }
380 }
381
382 priv->_3945.sta_supp_rates = sta->supp_rates[sband->band];
383 /* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
384 if (sband->band == IEEE80211_BAND_5GHZ) {
385 rs_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
386 priv->_3945.sta_supp_rates = priv->_3945.sta_supp_rates <<
387 IWL_FIRST_OFDM_RATE;
388 }
389
390out:
391 priv->stations[sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;
392
393 IWL_DEBUG_INFO(priv, "leave\n");
394}
395
be663ab6 396static void *iwl3945_rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
4bc85c13
WYG		 397{
398 return hw->priv;
399}
400
401/* rate scale requires free function to be implemented */
be663ab6 402static void iwl3945_rs_free(void *priv)
4bc85c13
WYG		 403{
404 return;
405}
406
be663ab6 407static void *iwl3945_rs_alloc_sta(void *iwl_priv, struct ieee80211_sta *sta, gfp_t gfp)
4bc85c13
WYG		 408{
409 struct iwl3945_rs_sta *rs_sta;
410 struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
411 struct iwl_priv *priv __maybe_unused = iwl_priv;
412
413 IWL_DEBUG_RATE(priv, "enter\n");
414
415 rs_sta = &psta->rs_sta;
416
417 spin_lock_init(&rs_sta->lock);
418 init_timer(&rs_sta->rate_scale_flush);
419
420 IWL_DEBUG_RATE(priv, "leave\n");
421
422 return rs_sta;
423}
424
be663ab6 425static void iwl3945_rs_free_sta(void *iwl_priv, struct ieee80211_sta *sta,
4bc85c13
WYG		 426 void *priv_sta)
427{
428 struct iwl3945_rs_sta *rs_sta = priv_sta;
429
430 /*
431 * Be careful not to use any members of iwl3945_rs_sta (like trying
432 * to use iwl_priv to print out debugging) since it may not be fully
433 * initialized at this point.
434 */
435 del_timer_sync(&rs_sta->rate_scale_flush);
436}
437
438
439/**
be663ab6 440 * iwl3945_rs_tx_status - Update rate control values based on Tx results
4bc85c13
WYG		 441 *
442 * NOTE: Uses iwl_priv->retry_rate for the # of retries attempted by
443 * the hardware for each rate.
444 */
be663ab6 445static void iwl3945_rs_tx_status(void *priv_rate, struct ieee80211_supported_band *sband,
4bc85c13
WYG		 446 struct ieee80211_sta *sta, void *priv_sta,
447 struct sk_buff *skb)
448{
449 s8 retries = 0, current_count;
450 int scale_rate_index, first_index, last_index;
451 unsigned long flags;
452 struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
453 struct iwl3945_rs_sta *rs_sta = priv_sta;
454 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
455
456 IWL_DEBUG_RATE(priv, "enter\n");
457
458 retries = info->status.rates[0].count;
459 /* Sanity Check for retries */
460 if (retries > IWL_RATE_RETRY_TH)
461 retries = IWL_RATE_RETRY_TH;
462
463 first_index = sband->bitrates[info->status.rates[0].idx].hw_value;
464 if ((first_index < 0) || (first_index >= IWL_RATE_COUNT_3945)) {
465 IWL_DEBUG_RATE(priv, "leave: Rate out of bounds: %d\n", first_index);
466 return;
467 }
468
469 if (!priv_sta) {
470 IWL_DEBUG_RATE(priv, "leave: No STA priv data to update!\n");
471 return;
472 }
473
474 /* Treat uninitialized rate scaling data same as non-existing. */
475 if (!rs_sta->priv) {
476 IWL_DEBUG_RATE(priv, "leave: STA priv data uninitialized!\n");
477 return;
478 }
479
480
481 rs_sta->tx_packets++;
482
483 scale_rate_index = first_index;
484 last_index = first_index;
485
486 /*
487 * Update the window for each rate. We determine which rates
488 * were Tx'd based on the total number of retries vs. the number
489 * of retries configured for each rate -- currently set to the
490 * priv value 'retry_rate' vs. rate specific
491 *
492 * On exit from this while loop last_index indicates the rate
493 * at which the frame was finally transmitted (or failed if no
494 * ACK)
495 */
496 while (retries > 1) {
497 if ((retries - 1) < priv->retry_rate) {
498 current_count = (retries - 1);
499 last_index = scale_rate_index;
500 } else {
501 current_count = priv->retry_rate;
502 last_index = iwl3945_rs_next_rate(priv,
503 scale_rate_index);
504 }
505
506 /* Update this rate accounting for as many retries
507 * as was used for it (per current_count) */
508 iwl3945_collect_tx_data(rs_sta,
509 &rs_sta->win[scale_rate_index],
510 0, current_count, scale_rate_index);
511 IWL_DEBUG_RATE(priv, "Update rate %d for %d retries.\n",
512 scale_rate_index, current_count);
513
514 retries -= current_count;
515
516 scale_rate_index = last_index;
517 }
518
519
520 /* Update the last index window with success/failure based on ACK */
521 IWL_DEBUG_RATE(priv, "Update rate %d with %s.\n",
522 last_index,
523 (info->flags & IEEE80211_TX_STAT_ACK) ?
524 "success" : "failure");
525 iwl3945_collect_tx_data(rs_sta,
526 &rs_sta->win[last_index],
527 info->flags & IEEE80211_TX_STAT_ACK, 1, last_index);
528
529 /* We updated the rate scale window -- if its been more than
530 * flush_time since the last run, schedule the flush
531 * again */
532 spin_lock_irqsave(&rs_sta->lock, flags);
533
534 if (!rs_sta->flush_pending &&
535 time_after(jiffies, rs_sta->last_flush +
536 rs_sta->flush_time)) {
537
538 rs_sta->last_partial_flush = jiffies;
539 rs_sta->flush_pending = 1;
540 mod_timer(&rs_sta->rate_scale_flush,
541 jiffies + rs_sta->flush_time);
542 }
543
544 spin_unlock_irqrestore(&rs_sta->lock, flags);
545
546 IWL_DEBUG_RATE(priv, "leave\n");
547}
548
549static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
550 u8 index, u16 rate_mask, enum ieee80211_band band)
551{
552 u8 high = IWL_RATE_INVALID;
553 u8 low = IWL_RATE_INVALID;
554 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
555
556 /* 802.11A walks to the next literal adjacent rate in
557 * the rate table */
558 if (unlikely(band == IEEE80211_BAND_5GHZ)) {
559 int i;
560 u32 mask;
561
562 /* Find the previous rate that is in the rate mask */
563 i = index - 1;
564 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
565 if (rate_mask & mask) {
566 low = i;
567 break;
568 }
569 }
570
571 /* Find the next rate that is in the rate mask */
572 i = index + 1;
573 for (mask = (1 << i); i < IWL_RATE_COUNT_3945;
574 i++, mask <<= 1) {
575 if (rate_mask & mask) {
576 high = i;
577 break;
578 }
579 }
580
581 return (high << 8) | low;
582 }
583
584 low = index;
585 while (low != IWL_RATE_INVALID) {
586 if (rs_sta->tgg)
587 low = iwl3945_rates[low].prev_rs_tgg;
588 else
589 low = iwl3945_rates[low].prev_rs;
590 if (low == IWL_RATE_INVALID)
591 break;
592 if (rate_mask & (1 << low))
593 break;
594 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
595 }
596
597 high = index;
598 while (high != IWL_RATE_INVALID) {
599 if (rs_sta->tgg)
600 high = iwl3945_rates[high].next_rs_tgg;
601 else
602 high = iwl3945_rates[high].next_rs;
603 if (high == IWL_RATE_INVALID)
604 break;
605 if (rate_mask & (1 << high))
606 break;
607 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
608 }
609
610 return (high << 8) | low;
611}
612
613/**
be663ab6 614 * iwl3945_rs_get_rate - find the rate for the requested packet
4bc85c13
WYG		 615 *
616 * Returns the ieee80211_rate structure allocated by the driver.
617 *
618 * The rate control algorithm has no internal mapping between hw_mode's
619 * rate ordering and the rate ordering used by the rate control algorithm.
620 *
621 * The rate control algorithm uses a single table of rates that goes across
622 * the entire A/B/G spectrum vs. being limited to just one particular
623 * hw_mode.
624 *
625 * As such, we can't convert the index obtained below into the hw_mode's
626 * rate table and must reference the driver allocated rate table
627 *
628 */
be663ab6 629static void iwl3945_rs_get_rate(void *priv_r, struct ieee80211_sta *sta,
4bc85c13
WYG		 630 void *priv_sta, struct ieee80211_tx_rate_control *txrc)
631{
632 struct ieee80211_supported_band *sband = txrc->sband;
633 struct sk_buff *skb = txrc->skb;
634 u8 low = IWL_RATE_INVALID;
635 u8 high = IWL_RATE_INVALID;
636 u16 high_low;
637 int index;
638 struct iwl3945_rs_sta *rs_sta = priv_sta;
639 struct iwl3945_rate_scale_data *window = NULL;
640 int current_tpt = IWL_INVALID_VALUE;
641 int low_tpt = IWL_INVALID_VALUE;
642 int high_tpt = IWL_INVALID_VALUE;
643 u32 fail_count;
644 s8 scale_action = 0;
645 unsigned long flags;
c3371d64 646 u16 rate_mask;
4bc85c13
WYG		 647 s8 max_rate_idx = -1;
648 struct iwl_priv *priv __maybe_unused = (struct iwl_priv *)priv_r;
649 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
650
651 IWL_DEBUG_RATE(priv, "enter\n");
652
653 /* Treat uninitialized rate scaling data same as non-existing. */
654 if (rs_sta && !rs_sta->priv) {
655 IWL_DEBUG_RATE(priv, "Rate scaling information not initialized yet.\n");
656 priv_sta = NULL;
657 }
658
659 if (rate_control_send_low(sta, priv_sta, txrc))
660 return;
661
662 rate_mask = sta->supp_rates[sband->band];
663
664 /* get user max rate if set */
665 max_rate_idx = txrc->max_rate_idx;
666 if ((sband->band == IEEE80211_BAND_5GHZ) && (max_rate_idx != -1))
667 max_rate_idx += IWL_FIRST_OFDM_RATE;
668 if ((max_rate_idx < 0) || (max_rate_idx >= IWL_RATE_COUNT))
669 max_rate_idx = -1;
670
671 index = min(rs_sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT_3945 - 1);
672
673 if (sband->band == IEEE80211_BAND_5GHZ)
674 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
675
676 spin_lock_irqsave(&rs_sta->lock, flags);
677
678 /* for recent assoc, choose best rate regarding
679 * to rssi value
680 */
681 if (rs_sta->start_rate != IWL_RATE_INVALID) {
682 if (rs_sta->start_rate < index &&
683 (rate_mask & (1 << rs_sta->start_rate)))
684 index = rs_sta->start_rate;
685 rs_sta->start_rate = IWL_RATE_INVALID;
686 }
687
688 /* force user max rate if set by user */
689 if ((max_rate_idx != -1) && (max_rate_idx < index)) {
690 if (rate_mask & (1 << max_rate_idx))
691 index = max_rate_idx;
692 }
693
694 window = &(rs_sta->win[index]);
695
696 fail_count = window->counter - window->success_counter;
697
698 if (((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
699 (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
700 spin_unlock_irqrestore(&rs_sta->lock, flags);
701
702 IWL_DEBUG_RATE(priv, "Invalid average_tpt on rate %d: "
703 "counter: %d, success_counter: %d, "
704 "expected_tpt is %sNULL\n",
705 index,
706 window->counter,
707 window->success_counter,
708 rs_sta->expected_tpt ? "not " : "");
709
710 /* Can't calculate this yet; not enough history */
711 window->average_tpt = IWL_INVALID_VALUE;
712 goto out;
713
714 }
715
716 current_tpt = window->average_tpt;
717
718 high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
719 sband->band);
720 low = high_low & 0xff;
721 high = (high_low >> 8) & 0xff;
722
723 /* If user set max rate, dont allow higher than user constrain */
724 if ((max_rate_idx != -1) && (max_rate_idx < high))
725 high = IWL_RATE_INVALID;
726
727 /* Collect Measured throughputs of adjacent rates */
728 if (low != IWL_RATE_INVALID)
729 low_tpt = rs_sta->win[low].average_tpt;
730
731 if (high != IWL_RATE_INVALID)
732 high_tpt = rs_sta->win[high].average_tpt;
733
734 spin_unlock_irqrestore(&rs_sta->lock, flags);
735
736 scale_action = 0;
737
738 /* Low success ratio , need to drop the rate */
739 if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
740 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
741 scale_action = -1;
742 /* No throughput measured yet for adjacent rates,
743 * try increase */
744 } else if ((low_tpt == IWL_INVALID_VALUE) &&
745 (high_tpt == IWL_INVALID_VALUE)) {
746
747 if (high != IWL_RATE_INVALID && window->success_ratio >= IWL_RATE_INCREASE_TH)
748 scale_action = 1;
749 else if (low != IWL_RATE_INVALID)
750 scale_action = 0;
751
752 /* Both adjacent throughputs are measured, but neither one has
753 * better throughput; we're using the best rate, don't change
754 * it! */
755 } else if ((low_tpt != IWL_INVALID_VALUE) &&
756 (high_tpt != IWL_INVALID_VALUE) &&
757 (low_tpt < current_tpt) && (high_tpt < current_tpt)) {
758
759 IWL_DEBUG_RATE(priv, "No action -- low [%d] & high [%d] < "
760 "current_tpt [%d]\n",
761 low_tpt, high_tpt, current_tpt);
762 scale_action = 0;
763
764 /* At least one of the rates has better throughput */
765 } else {
766 if (high_tpt != IWL_INVALID_VALUE) {
767
768 /* High rate has better throughput, Increase
769 * rate */
770 if (high_tpt > current_tpt &&
771 window->success_ratio >= IWL_RATE_INCREASE_TH)
772 scale_action = 1;
773 else {
774 IWL_DEBUG_RATE(priv,
775 "decrease rate because of high tpt\n");
776 scale_action = 0;
777 }
778 } else if (low_tpt != IWL_INVALID_VALUE) {
779 if (low_tpt > current_tpt) {
780 IWL_DEBUG_RATE(priv,
781 "decrease rate because of low tpt\n");
782 scale_action = -1;
783 } else if (window->success_ratio >= IWL_RATE_INCREASE_TH) {
784 /* Lower rate has better
785 * throughput,decrease rate */
786 scale_action = 1;
787 }
788 }
789 }
790
791 /* Sanity check; asked for decrease, but success rate or throughput
792 * has been good at old rate. Don't change it. */
793 if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
794 ((window->success_ratio > IWL_RATE_HIGH_TH) ||
795 (current_tpt > (100 * rs_sta->expected_tpt[low]))))
796 scale_action = 0;
797
798 switch (scale_action) {
799 case -1:
800
801 /* Decrese rate */
802 if (low != IWL_RATE_INVALID)
803 index = low;
804 break;
805
806 case 1:
807 /* Increase rate */
808 if (high != IWL_RATE_INVALID)
809 index = high;
810
811 break;
812
813 case 0:
814 default:
815 /* No change */
816 break;
817 }
818
819 IWL_DEBUG_RATE(priv, "Selected %d (action %d) - low %d high %d\n",
820 index, scale_action, low, high);
821
822 out:
823
824 rs_sta->last_txrate_idx = index;
825 if (sband->band == IEEE80211_BAND_5GHZ)
826 info->control.rates[0].idx = rs_sta->last_txrate_idx -
827 IWL_FIRST_OFDM_RATE;
828 else
829 info->control.rates[0].idx = rs_sta->last_txrate_idx;
830
831 IWL_DEBUG_RATE(priv, "leave: %d\n", index);
832}
833
834#ifdef CONFIG_MAC80211_DEBUGFS
835static int iwl3945_open_file_generic(struct inode *inode, struct file *file)
836{
837 file->private_data = inode->i_private;
838 return 0;
839}
840
841static ssize_t iwl3945_sta_dbgfs_stats_table_read(struct file *file,
842 char __user *user_buf,
843 size_t count, loff_t *ppos)
844{
845 char *buff;
846 int desc = 0;
847 int j;
848 ssize_t ret;
849 struct iwl3945_rs_sta *lq_sta = file->private_data;
850
851 buff = kmalloc(1024, GFP_KERNEL);
852 if (!buff)
853 return -ENOMEM;
854
855 desc += sprintf(buff + desc, "tx packets=%d last rate index=%d\n"
856 "rate=0x%X flush time %d\n",
857 lq_sta->tx_packets,
858 lq_sta->last_txrate_idx,
859 lq_sta->start_rate, jiffies_to_msecs(lq_sta->flush_time));
860 for (j = 0; j < IWL_RATE_COUNT_3945; j++) {
861 desc += sprintf(buff+desc,
862 "counter=%d success=%d %%=%d\n",
863 lq_sta->win[j].counter,
864 lq_sta->win[j].success_counter,
865 lq_sta->win[j].success_ratio);
866 }
867 ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
868 kfree(buff);
869 return ret;
870}
871
872static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
873 .read = iwl3945_sta_dbgfs_stats_table_read,
874 .open = iwl3945_open_file_generic,
875 .llseek = default_llseek,
876};
877
878static void iwl3945_add_debugfs(void *priv, void *priv_sta,
879 struct dentry *dir)
880{
881 struct iwl3945_rs_sta *lq_sta = priv_sta;
882
883 lq_sta->rs_sta_dbgfs_stats_table_file =
884 debugfs_create_file("rate_stats_table", 0600, dir,
885 lq_sta, &rs_sta_dbgfs_stats_table_ops);
886
887}
888
889static void iwl3945_remove_debugfs(void *priv, void *priv_sta)
890{
891 struct iwl3945_rs_sta *lq_sta = priv_sta;
892 debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
893}
894#endif
895
896/*
897 * Initialization of rate scaling information is done by driver after
898 * the station is added. Since mac80211 calls this function before a
899 * station is added we ignore it.
900 */
be663ab6
WYG		 901static void iwl3945_rs_rate_init_stub(void *priv_r,
902 struct ieee80211_supported_band *sband,
4bc85c13
WYG		 903 struct ieee80211_sta *sta, void *priv_sta)
904{
905}
906
907static struct rate_control_ops rs_ops = {
908 .module = NULL,
909 .name = RS_NAME,
be663ab6
WYG		 910 .tx_status = iwl3945_rs_tx_status,
911 .get_rate = iwl3945_rs_get_rate,
912 .rate_init = iwl3945_rs_rate_init_stub,
913 .alloc = iwl3945_rs_alloc,
914 .free = iwl3945_rs_free,
915 .alloc_sta = iwl3945_rs_alloc_sta,
916 .free_sta = iwl3945_rs_free_sta,
4bc85c13
WYG		 917#ifdef CONFIG_MAC80211_DEBUGFS
918 .add_sta_debugfs = iwl3945_add_debugfs,
919 .remove_sta_debugfs = iwl3945_remove_debugfs,
920#endif
921
922};
923void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
924{
925 struct iwl_priv *priv = hw->priv;
926 s32 rssi = 0;
927 unsigned long flags;
928 struct iwl3945_rs_sta *rs_sta;
929 struct ieee80211_sta *sta;
930 struct iwl3945_sta_priv *psta;
931
932 IWL_DEBUG_RATE(priv, "enter\n");
933
934 rcu_read_lock();
935
936 sta = ieee80211_find_sta(priv->contexts[IWL_RXON_CTX_BSS].vif,
937 priv->stations[sta_id].sta.sta.addr);
938 if (!sta) {
939 IWL_DEBUG_RATE(priv, "Unable to find station to initialize rate scaling.\n");
940 rcu_read_unlock();
941 return;
942 }
943
944 psta = (void *) sta->drv_priv;
945 rs_sta = &psta->rs_sta;
946
947 spin_lock_irqsave(&rs_sta->lock, flags);
948
949 rs_sta->tgg = 0;
950 switch (priv->band) {
951 case IEEE80211_BAND_2GHZ:
952 /* TODO: this always does G, not a regression */
953 if (priv->contexts[IWL_RXON_CTX_BSS].active.flags &
954 RXON_FLG_TGG_PROTECT_MSK) {
955 rs_sta->tgg = 1;
956 rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
957 } else
958 rs_sta->expected_tpt = iwl3945_expected_tpt_g;
959 break;
960
961 case IEEE80211_BAND_5GHZ:
962 rs_sta->expected_tpt = iwl3945_expected_tpt_a;
963 break;
964 case IEEE80211_NUM_BANDS:
965 BUG();
966 break;
967 }
968
969 spin_unlock_irqrestore(&rs_sta->lock, flags);
970
971 rssi = priv->_3945.last_rx_rssi;
972 if (rssi == 0)
973 rssi = IWL_MIN_RSSI_VAL;
974
975 IWL_DEBUG_RATE(priv, "Network RSSI: %d\n", rssi);
976
977 rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
978
979 IWL_DEBUG_RATE(priv, "leave: rssi %d assign rate index: "
980 "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
981 iwl3945_rates[rs_sta->start_rate].plcp);
982 rcu_read_unlock();
983}
984
985int iwl3945_rate_control_register(void)
986{
987 return ieee80211_rate_control_register(&rs_ops);
988}
989
990void iwl3945_rate_control_unregister(void)
991{
992 ieee80211_rate_control_unregister(&rs_ops);
993}
Linux kernel - Deliverables
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