aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/wireless/iwlegacy/iwl-3945-rs.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/net/wireless/iwlegacy/iwl-3945-rs.c')
-rw-r--r--drivers/net/wireless/iwlegacy/iwl-3945-rs.c994
1 files changed, 994 insertions, 0 deletions
diff --git a/drivers/net/wireless/iwlegacy/iwl-3945-rs.c b/drivers/net/wireless/iwlegacy/iwl-3945-rs.c
new file mode 100644
index 000000000000..4fabc5439858
--- /dev/null
+++ b/drivers/net/wireless/iwlegacy/iwl-3945-rs.c
@@ -0,0 +1,994 @@
1/******************************************************************************
2 *
3 * Copyright(c) 2005 - 2011 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
46static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT_3945] = {
47 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
48};
49
50static 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
54static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT_3945] = {
55 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
56};
57
58static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT_3945] = {
59 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
60};
61
62struct iwl3945_tpt_entry {
63 s8 min_rssi;
64 u8 index;
65};
66
67static 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
78static 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
102static 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
135static 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 */
152static 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
187static 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 */
258static 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/*
334 * Called after adding a new station to initialize rate scaling
335 */
336void iwl3945_rs_rate_init(struct iwl_priv *priv, struct ieee80211_sta *sta, u8 sta_id)
337{
338 struct ieee80211_hw *hw = priv->hw;
339 struct ieee80211_conf *conf = &priv->hw->conf;
340 struct iwl3945_sta_priv *psta;
341 struct iwl3945_rs_sta *rs_sta;
342 struct ieee80211_supported_band *sband;
343 int i;
344
345 IWL_DEBUG_INFO(priv, "enter\n");
346 if (sta_id == priv->contexts[IWL_RXON_CTX_BSS].bcast_sta_id)
347 goto out;
348
349 psta = (struct iwl3945_sta_priv *) sta->drv_priv;
350 rs_sta = &psta->rs_sta;
351 sband = hw->wiphy->bands[conf->channel->band];
352
353 rs_sta->priv = priv;
354
355 rs_sta->start_rate = IWL_RATE_INVALID;
356
357 /* default to just 802.11b */
358 rs_sta->expected_tpt = iwl3945_expected_tpt_b;
359
360 rs_sta->last_partial_flush = jiffies;
361 rs_sta->last_flush = jiffies;
362 rs_sta->flush_time = IWL_RATE_FLUSH;
363 rs_sta->last_tx_packets = 0;
364
365 rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
366 rs_sta->rate_scale_flush.function = iwl3945_bg_rate_scale_flush;
367
368 for (i = 0; i < IWL_RATE_COUNT_3945; i++)
369 iwl3945_clear_window(&rs_sta->win[i]);
370
371 /* TODO: what is a good starting rate for STA? About middle? Maybe not
372 * the lowest or the highest rate.. Could consider using RSSI from
373 * previous packets? Need to have IEEE 802.1X auth succeed immediately
374 * after assoc.. */
375
376 for (i = sband->n_bitrates - 1; i >= 0; i--) {
377 if (sta->supp_rates[sband->band] & (1 << i)) {
378 rs_sta->last_txrate_idx = i;
379 break;
380 }
381 }
382
383 priv->_3945.sta_supp_rates = sta->supp_rates[sband->band];
384 /* For 5 GHz band it start at IWL_FIRST_OFDM_RATE */
385 if (sband->band == IEEE80211_BAND_5GHZ) {
386 rs_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
387 priv->_3945.sta_supp_rates = priv->_3945.sta_supp_rates <<
388 IWL_FIRST_OFDM_RATE;
389 }
390
391out:
392 priv->stations[sta_id].used &= ~IWL_STA_UCODE_INPROGRESS;
393
394 IWL_DEBUG_INFO(priv, "leave\n");
395}
396
397static void *iwl3945_rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
398{
399 return hw->priv;
400}
401
402/* rate scale requires free function to be implemented */
403static void iwl3945_rs_free(void *priv)
404{
405 return;
406}
407
408static void *iwl3945_rs_alloc_sta(void *iwl_priv, struct ieee80211_sta *sta, gfp_t gfp)
409{
410 struct iwl3945_rs_sta *rs_sta;
411 struct iwl3945_sta_priv *psta = (void *) sta->drv_priv;
412 struct iwl_priv *priv __maybe_unused = iwl_priv;
413
414 IWL_DEBUG_RATE(priv, "enter\n");
415
416 rs_sta = &psta->rs_sta;
417
418 spin_lock_init(&rs_sta->lock);
419 init_timer(&rs_sta->rate_scale_flush);
420
421 IWL_DEBUG_RATE(priv, "leave\n");
422
423 return rs_sta;
424}
425
426static void iwl3945_rs_free_sta(void *iwl_priv, struct ieee80211_sta *sta,
427 void *priv_sta)
428{
429 struct iwl3945_rs_sta *rs_sta = priv_sta;
430
431 /*
432 * Be careful not to use any members of iwl3945_rs_sta (like trying
433 * to use iwl_priv to print out debugging) since it may not be fully
434 * initialized at this point.
435 */
436 del_timer_sync(&rs_sta->rate_scale_flush);
437}
438
439
440/**
441 * iwl3945_rs_tx_status - Update rate control values based on Tx results
442 *
443 * NOTE: Uses iwl_priv->retry_rate for the # of retries attempted by
444 * the hardware for each rate.
445 */
446static void iwl3945_rs_tx_status(void *priv_rate, struct ieee80211_supported_band *sband,
447 struct ieee80211_sta *sta, void *priv_sta,
448 struct sk_buff *skb)
449{
450 s8 retries = 0, current_count;
451 int scale_rate_index, first_index, last_index;
452 unsigned long flags;
453 struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
454 struct iwl3945_rs_sta *rs_sta = priv_sta;
455 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
456
457 IWL_DEBUG_RATE(priv, "enter\n");
458
459 retries = info->status.rates[0].count;
460 /* Sanity Check for retries */
461 if (retries > IWL_RATE_RETRY_TH)
462 retries = IWL_RATE_RETRY_TH;
463
464 first_index = sband->bitrates[info->status.rates[0].idx].hw_value;
465 if ((first_index < 0) || (first_index >= IWL_RATE_COUNT_3945)) {
466 IWL_DEBUG_RATE(priv, "leave: Rate out of bounds: %d\n", first_index);
467 return;
468 }
469
470 if (!priv_sta) {
471 IWL_DEBUG_RATE(priv, "leave: No STA priv data to update!\n");
472 return;
473 }
474
475 /* Treat uninitialized rate scaling data same as non-existing. */
476 if (!rs_sta->priv) {
477 IWL_DEBUG_RATE(priv, "leave: STA priv data uninitialized!\n");
478 return;
479 }
480
481
482 rs_sta->tx_packets++;
483
484 scale_rate_index = first_index;
485 last_index = first_index;
486
487 /*
488 * Update the window for each rate. We determine which rates
489 * were Tx'd based on the total number of retries vs. the number
490 * of retries configured for each rate -- currently set to the
491 * priv value 'retry_rate' vs. rate specific
492 *
493 * On exit from this while loop last_index indicates the rate
494 * at which the frame was finally transmitted (or failed if no
495 * ACK)
496 */
497 while (retries > 1) {
498 if ((retries - 1) < priv->retry_rate) {
499 current_count = (retries - 1);
500 last_index = scale_rate_index;
501 } else {
502 current_count = priv->retry_rate;
503 last_index = iwl3945_rs_next_rate(priv,
504 scale_rate_index);
505 }
506
507 /* Update this rate accounting for as many retries
508 * as was used for it (per current_count) */
509 iwl3945_collect_tx_data(rs_sta,
510 &rs_sta->win[scale_rate_index],
511 0, current_count, scale_rate_index);
512 IWL_DEBUG_RATE(priv, "Update rate %d for %d retries.\n",
513 scale_rate_index, current_count);
514
515 retries -= current_count;
516
517 scale_rate_index = last_index;
518 }
519
520
521 /* Update the last index window with success/failure based on ACK */
522 IWL_DEBUG_RATE(priv, "Update rate %d with %s.\n",
523 last_index,
524 (info->flags & IEEE80211_TX_STAT_ACK) ?
525 "success" : "failure");
526 iwl3945_collect_tx_data(rs_sta,
527 &rs_sta->win[last_index],
528 info->flags & IEEE80211_TX_STAT_ACK, 1, last_index);
529
530 /* We updated the rate scale window -- if its been more than
531 * flush_time since the last run, schedule the flush
532 * again */
533 spin_lock_irqsave(&rs_sta->lock, flags);
534
535 if (!rs_sta->flush_pending &&
536 time_after(jiffies, rs_sta->last_flush +
537 rs_sta->flush_time)) {
538
539 rs_sta->last_partial_flush = jiffies;
540 rs_sta->flush_pending = 1;
541 mod_timer(&rs_sta->rate_scale_flush,
542 jiffies + rs_sta->flush_time);
543 }
544
545 spin_unlock_irqrestore(&rs_sta->lock, flags);
546
547 IWL_DEBUG_RATE(priv, "leave\n");
548}
549
550static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
551 u8 index, u16 rate_mask, enum ieee80211_band band)
552{
553 u8 high = IWL_RATE_INVALID;
554 u8 low = IWL_RATE_INVALID;
555 struct iwl_priv *priv __maybe_unused = rs_sta->priv;
556
557 /* 802.11A walks to the next literal adjacent rate in
558 * the rate table */
559 if (unlikely(band == IEEE80211_BAND_5GHZ)) {
560 int i;
561 u32 mask;
562
563 /* Find the previous rate that is in the rate mask */
564 i = index - 1;
565 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
566 if (rate_mask & mask) {
567 low = i;
568 break;
569 }
570 }
571
572 /* Find the next rate that is in the rate mask */
573 i = index + 1;
574 for (mask = (1 << i); i < IWL_RATE_COUNT_3945;
575 i++, mask <<= 1) {
576 if (rate_mask & mask) {
577 high = i;
578 break;
579 }
580 }
581
582 return (high << 8) | low;
583 }
584
585 low = index;
586 while (low != IWL_RATE_INVALID) {
587 if (rs_sta->tgg)
588 low = iwl3945_rates[low].prev_rs_tgg;
589 else
590 low = iwl3945_rates[low].prev_rs;
591 if (low == IWL_RATE_INVALID)
592 break;
593 if (rate_mask & (1 << low))
594 break;
595 IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
596 }
597
598 high = index;
599 while (high != IWL_RATE_INVALID) {
600 if (rs_sta->tgg)
601 high = iwl3945_rates[high].next_rs_tgg;
602 else
603 high = iwl3945_rates[high].next_rs;
604 if (high == IWL_RATE_INVALID)
605 break;
606 if (rate_mask & (1 << high))
607 break;
608 IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
609 }
610
611 return (high << 8) | low;
612}
613
614/**
615 * iwl3945_rs_get_rate - find the rate for the requested packet
616 *
617 * Returns the ieee80211_rate structure allocated by the driver.
618 *
619 * The rate control algorithm has no internal mapping between hw_mode's
620 * rate ordering and the rate ordering used by the rate control algorithm.
621 *
622 * The rate control algorithm uses a single table of rates that goes across
623 * the entire A/B/G spectrum vs. being limited to just one particular
624 * hw_mode.
625 *
626 * As such, we can't convert the index obtained below into the hw_mode's
627 * rate table and must reference the driver allocated rate table
628 *
629 */
630static void iwl3945_rs_get_rate(void *priv_r, struct ieee80211_sta *sta,
631 void *priv_sta, struct ieee80211_tx_rate_control *txrc)
632{
633 struct ieee80211_supported_band *sband = txrc->sband;
634 struct sk_buff *skb = txrc->skb;
635 u8 low = IWL_RATE_INVALID;
636 u8 high = IWL_RATE_INVALID;
637 u16 high_low;
638 int index;
639 struct iwl3945_rs_sta *rs_sta = priv_sta;
640 struct iwl3945_rate_scale_data *window = NULL;
641 int current_tpt = IWL_INVALID_VALUE;
642 int low_tpt = IWL_INVALID_VALUE;
643 int high_tpt = IWL_INVALID_VALUE;
644 u32 fail_count;
645 s8 scale_action = 0;
646 unsigned long flags;
647 u16 rate_mask = sta ? sta->supp_rates[sband->band] : 0;
648 s8 max_rate_idx = -1;
649 struct iwl_priv *priv __maybe_unused = (struct iwl_priv *)priv_r;
650 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
651
652 IWL_DEBUG_RATE(priv, "enter\n");
653
654 /* Treat uninitialized rate scaling data same as non-existing. */
655 if (rs_sta && !rs_sta->priv) {
656 IWL_DEBUG_RATE(priv, "Rate scaling information not initialized yet.\n");
657 priv_sta = NULL;
658 }
659
660 if (rate_control_send_low(sta, priv_sta, txrc))
661 return;
662
663 rate_mask = sta->supp_rates[sband->band];
664
665 /* get user max rate if set */
666 max_rate_idx = txrc->max_rate_idx;
667 if ((sband->band == IEEE80211_BAND_5GHZ) && (max_rate_idx != -1))
668 max_rate_idx += IWL_FIRST_OFDM_RATE;
669 if ((max_rate_idx < 0) || (max_rate_idx >= IWL_RATE_COUNT))
670 max_rate_idx = -1;
671
672 index = min(rs_sta->last_txrate_idx & 0xffff, IWL_RATE_COUNT_3945 - 1);
673
674 if (sband->band == IEEE80211_BAND_5GHZ)
675 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
676
677 spin_lock_irqsave(&rs_sta->lock, flags);
678
679 /* for recent assoc, choose best rate regarding
680 * to rssi value
681 */
682 if (rs_sta->start_rate != IWL_RATE_INVALID) {
683 if (rs_sta->start_rate < index &&
684 (rate_mask & (1 << rs_sta->start_rate)))
685 index = rs_sta->start_rate;
686 rs_sta->start_rate = IWL_RATE_INVALID;
687 }
688
689 /* force user max rate if set by user */
690 if ((max_rate_idx != -1) && (max_rate_idx < index)) {
691 if (rate_mask & (1 << max_rate_idx))
692 index = max_rate_idx;
693 }
694
695 window = &(rs_sta->win[index]);
696
697 fail_count = window->counter - window->success_counter;
698
699 if (((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
700 (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
701 spin_unlock_irqrestore(&rs_sta->lock, flags);
702
703 IWL_DEBUG_RATE(priv, "Invalid average_tpt on rate %d: "
704 "counter: %d, success_counter: %d, "
705 "expected_tpt is %sNULL\n",
706 index,
707 window->counter,
708 window->success_counter,
709 rs_sta->expected_tpt ? "not " : "");
710
711 /* Can't calculate this yet; not enough history */
712 window->average_tpt = IWL_INVALID_VALUE;
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 user set max rate, dont allow higher than user constrain */
725 if ((max_rate_idx != -1) && (max_rate_idx < high))
726 high = IWL_RATE_INVALID;
727
728 /* Collect Measured throughputs of adjacent rates */
729 if (low != IWL_RATE_INVALID)
730 low_tpt = rs_sta->win[low].average_tpt;
731
732 if (high != IWL_RATE_INVALID)
733 high_tpt = rs_sta->win[high].average_tpt;
734
735 spin_unlock_irqrestore(&rs_sta->lock, flags);
736
737 scale_action = 0;
738
739 /* Low success ratio , need to drop the rate */
740 if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
741 IWL_DEBUG_RATE(priv, "decrease rate because of low success_ratio\n");
742 scale_action = -1;
743 /* No throughput measured yet for adjacent rates,
744 * try increase */
745 } else if ((low_tpt == IWL_INVALID_VALUE) &&
746 (high_tpt == IWL_INVALID_VALUE)) {
747
748 if (high != IWL_RATE_INVALID && window->success_ratio >= IWL_RATE_INCREASE_TH)
749 scale_action = 1;
750 else if (low != IWL_RATE_INVALID)
751 scale_action = 0;
752
753 /* Both adjacent throughputs are measured, but neither one has
754 * better throughput; we're using the best rate, don't change
755 * it! */
756 } else if ((low_tpt != IWL_INVALID_VALUE) &&
757 (high_tpt != IWL_INVALID_VALUE) &&
758 (low_tpt < current_tpt) && (high_tpt < current_tpt)) {
759
760 IWL_DEBUG_RATE(priv, "No action -- low [%d] & high [%d] < "
761 "current_tpt [%d]\n",
762 low_tpt, high_tpt, current_tpt);
763 scale_action = 0;
764
765 /* At least one of the rates has better throughput */
766 } else {
767 if (high_tpt != IWL_INVALID_VALUE) {
768
769 /* High rate has better throughput, Increase
770 * rate */
771 if (high_tpt > current_tpt &&
772 window->success_ratio >= IWL_RATE_INCREASE_TH)
773 scale_action = 1;
774 else {
775 IWL_DEBUG_RATE(priv,
776 "decrease rate because of high tpt\n");
777 scale_action = 0;
778 }
779 } else if (low_tpt != IWL_INVALID_VALUE) {
780 if (low_tpt > current_tpt) {
781 IWL_DEBUG_RATE(priv,
782 "decrease rate because of low tpt\n");
783 scale_action = -1;
784 } else if (window->success_ratio >= IWL_RATE_INCREASE_TH) {
785 /* Lower rate has better
786 * throughput,decrease rate */
787 scale_action = 1;
788 }
789 }
790 }
791
792 /* Sanity check; asked for decrease, but success rate or throughput
793 * has been good at old rate. Don't change it. */
794 if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
795 ((window->success_ratio > IWL_RATE_HIGH_TH) ||
796 (current_tpt > (100 * rs_sta->expected_tpt[low]))))
797 scale_action = 0;
798
799 switch (scale_action) {
800 case -1:
801
802 /* Decrese rate */
803 if (low != IWL_RATE_INVALID)
804 index = low;
805 break;
806
807 case 1:
808 /* Increase rate */
809 if (high != IWL_RATE_INVALID)
810 index = high;
811
812 break;
813
814 case 0:
815 default:
816 /* No change */
817 break;
818 }
819
820 IWL_DEBUG_RATE(priv, "Selected %d (action %d) - low %d high %d\n",
821 index, scale_action, low, high);
822
823 out:
824
825 rs_sta->last_txrate_idx = index;
826 if (sband->band == IEEE80211_BAND_5GHZ)
827 info->control.rates[0].idx = rs_sta->last_txrate_idx -
828 IWL_FIRST_OFDM_RATE;
829 else
830 info->control.rates[0].idx = rs_sta->last_txrate_idx;
831
832 IWL_DEBUG_RATE(priv, "leave: %d\n", index);
833}
834
835#ifdef CONFIG_MAC80211_DEBUGFS
836static int iwl3945_open_file_generic(struct inode *inode, struct file *file)
837{
838 file->private_data = inode->i_private;
839 return 0;
840}
841
842static ssize_t iwl3945_sta_dbgfs_stats_table_read(struct file *file,
843 char __user *user_buf,
844 size_t count, loff_t *ppos)
845{
846 char *buff;
847 int desc = 0;
848 int j;
849 ssize_t ret;
850 struct iwl3945_rs_sta *lq_sta = file->private_data;
851
852 buff = kmalloc(1024, GFP_KERNEL);
853 if (!buff)
854 return -ENOMEM;
855
856 desc += sprintf(buff + desc, "tx packets=%d last rate index=%d\n"
857 "rate=0x%X flush time %d\n",
858 lq_sta->tx_packets,
859 lq_sta->last_txrate_idx,
860 lq_sta->start_rate, jiffies_to_msecs(lq_sta->flush_time));
861 for (j = 0; j < IWL_RATE_COUNT_3945; j++) {
862 desc += sprintf(buff+desc,
863 "counter=%d success=%d %%=%d\n",
864 lq_sta->win[j].counter,
865 lq_sta->win[j].success_counter,
866 lq_sta->win[j].success_ratio);
867 }
868 ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
869 kfree(buff);
870 return ret;
871}
872
873static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
874 .read = iwl3945_sta_dbgfs_stats_table_read,
875 .open = iwl3945_open_file_generic,
876 .llseek = default_llseek,
877};
878
879static void iwl3945_add_debugfs(void *priv, void *priv_sta,
880 struct dentry *dir)
881{
882 struct iwl3945_rs_sta *lq_sta = priv_sta;
883
884 lq_sta->rs_sta_dbgfs_stats_table_file =
885 debugfs_create_file("rate_stats_table", 0600, dir,
886 lq_sta, &rs_sta_dbgfs_stats_table_ops);
887
888}
889
890static void iwl3945_remove_debugfs(void *priv, void *priv_sta)
891{
892 struct iwl3945_rs_sta *lq_sta = priv_sta;
893 debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
894}
895#endif
896
897/*
898 * Initialization of rate scaling information is done by driver after
899 * the station is added. Since mac80211 calls this function before a
900 * station is added we ignore it.
901 */
902static void iwl3945_rs_rate_init_stub(void *priv_r,
903 struct ieee80211_supported_band *sband,
904 struct ieee80211_sta *sta, void *priv_sta)
905{
906}
907
908static struct rate_control_ops rs_ops = {
909 .module = NULL,
910 .name = RS_NAME,
911 .tx_status = iwl3945_rs_tx_status,
912 .get_rate = iwl3945_rs_get_rate,
913 .rate_init = iwl3945_rs_rate_init_stub,
914 .alloc = iwl3945_rs_alloc,
915 .free = iwl3945_rs_free,
916 .alloc_sta = iwl3945_rs_alloc_sta,
917 .free_sta = iwl3945_rs_free_sta,
918#ifdef CONFIG_MAC80211_DEBUGFS
919 .add_sta_debugfs = iwl3945_add_debugfs,
920 .remove_sta_debugfs = iwl3945_remove_debugfs,
921#endif
922
923};
924void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
925{
926 struct iwl_priv *priv = hw->priv;
927 s32 rssi = 0;
928 unsigned long flags;
929 struct iwl3945_rs_sta *rs_sta;
930 struct ieee80211_sta *sta;
931 struct iwl3945_sta_priv *psta;
932
933 IWL_DEBUG_RATE(priv, "enter\n");
934
935 rcu_read_lock();
936
937 sta = ieee80211_find_sta(priv->contexts[IWL_RXON_CTX_BSS].vif,
938 priv->stations[sta_id].sta.sta.addr);
939 if (!sta) {
940 IWL_DEBUG_RATE(priv, "Unable to find station to initialize rate scaling.\n");
941 rcu_read_unlock();
942 return;
943 }
944
945 psta = (void *) sta->drv_priv;
946 rs_sta = &psta->rs_sta;
947
948 spin_lock_irqsave(&rs_sta->lock, flags);
949
950 rs_sta->tgg = 0;
951 switch (priv->band) {
952 case IEEE80211_BAND_2GHZ:
953 /* TODO: this always does G, not a regression */
954 if (priv->contexts[IWL_RXON_CTX_BSS].active.flags &
955 RXON_FLG_TGG_PROTECT_MSK) {
956 rs_sta->tgg = 1;
957 rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
958 } else
959 rs_sta->expected_tpt = iwl3945_expected_tpt_g;
960 break;
961
962 case IEEE80211_BAND_5GHZ:
963 rs_sta->expected_tpt = iwl3945_expected_tpt_a;
964 break;
965 case IEEE80211_NUM_BANDS:
966 BUG();
967 break;
968 }
969
970 spin_unlock_irqrestore(&rs_sta->lock, flags);
971
972 rssi = priv->_3945.last_rx_rssi;
973 if (rssi == 0)
974 rssi = IWL_MIN_RSSI_VAL;
975
976 IWL_DEBUG_RATE(priv, "Network RSSI: %d\n", rssi);
977
978 rs_sta->start_rate = iwl3945_get_rate_index_by_rssi(rssi, priv->band);
979
980 IWL_DEBUG_RATE(priv, "leave: rssi %d assign rate index: "
981 "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
982 iwl3945_rates[rs_sta->start_rate].plcp);
983 rcu_read_unlock();
984}
985
986int iwl3945_rate_control_register(void)
987{
988 return ieee80211_rate_control_register(&rs_ops);
989}
990
991void iwl3945_rate_control_unregister(void)
992{
993 ieee80211_rate_control_unregister(&rs_ops);
994}
generated by cgit v1.2.2 (git 2.25.0) at 2026-01-09 04:52:45 -0500