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Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
[linux-2.6-block.git] / net / mac80211 / rc80211_minstrel_ht.c
CommitLineData
ec8aa669 1/*
a0497f9f 2 * Copyright (C) 2010-2013 Felix Fietkau <nbd@openwrt.org>
ec8aa669
FF		 3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8#include <linux/netdevice.h>
9#include <linux/types.h>
10#include <linux/skbuff.h>
11#include <linux/debugfs.h>
12#include <linux/random.h>
9208247d 13#include <linux/moduleparam.h>
ec8aa669
FF		 14#include <linux/ieee80211.h>
15#include <net/mac80211.h>
16#include "rate.h"
782dda00 17#include "sta_info.h"
ec8aa669
FF		 18#include "rc80211_minstrel.h"
19#include "rc80211_minstrel_ht.h"
20
d66c2582 21#define AVG_AMPDU_SIZE 16
ec8aa669 22#define AVG_PKT_SIZE 1200
ec8aa669
FF		 23
24/* Number of bits for an average sized packet */
d66c2582 25#define MCS_NBITS ((AVG_PKT_SIZE * AVG_AMPDU_SIZE) << 3)
ec8aa669
FF		 26
27/* Number of symbols for a packet with (bps) bits per symbol */
00591cea 28#define MCS_NSYMS(bps) DIV_ROUND_UP(MCS_NBITS, (bps))
ec8aa669 29
ed97a13c 30/* Transmission time (nanoseconds) for a packet containing (syms) symbols */
ec8aa669
FF		 31#define MCS_SYMBOL_TIME(sgi, syms) \
32 (sgi ? \
ed97a13c
FF		 33 ((syms) * 18000 + 4000) / 5 : /* syms * 3.6 us */ \
34 ((syms) * 1000) << 2 /* syms * 4 us */ \
ec8aa669
FF		 35 )
36
37/* Transmit duration for the raw data part of an average sized packet */
d66c2582
FF		 38#define MCS_DURATION(streams, sgi, bps) \
39 (MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps))) / AVG_AMPDU_SIZE)
ec8aa669 40
8a0ee4fe
KB		 41#define BW_20 0
42#define BW_40 1
9208247d 43#define BW_80 2
8a0ee4fe 44
a5f69d94
HS		 45/*
46 * Define group sort order: HT40 -> SGI -> #streams
47 */
48#define GROUP_IDX(_streams, _sgi, _ht40) \
8a0ee4fe 49 MINSTREL_HT_GROUP_0 + \
a5f69d94 50 MINSTREL_MAX_STREAMS * 2 * _ht40 + \
8a0ee4fe 51 MINSTREL_MAX_STREAMS * _sgi + \
a5f69d94
HS		 52 _streams - 1
53
ec8aa669 54/* MCS rate information for an MCS group */
a5f69d94
HS		 55#define MCS_GROUP(_streams, _sgi, _ht40) \
56 [GROUP_IDX(_streams, _sgi, _ht40)] = { \
ec8aa669
FF		 57 .streams = _streams, \
58 .flags = \
3ec373c4 59 IEEE80211_TX_RC_MCS | \
ec8aa669
FF		 60 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
61 (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
62 .duration = { \
63 MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \
64 MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \
65 MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \
66 MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \
67 MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \
68 MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \
69 MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \
70 MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \
71 } \
72}
73
9208247d
KB		 74#define VHT_GROUP_IDX(_streams, _sgi, _bw) \
75 (MINSTREL_VHT_GROUP_0 + \
76 MINSTREL_MAX_STREAMS * 2 * (_bw) + \
77 MINSTREL_MAX_STREAMS * (_sgi) + \
78 (_streams) - 1)
79
80#define BW2VBPS(_bw, r3, r2, r1) \
81 (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1)
82
83#define VHT_GROUP(_streams, _sgi, _bw) \
84 [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \
85 .streams = _streams, \
86 .flags = \
87 IEEE80211_TX_RC_VHT_MCS | \
88 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
89 (_bw == BW_80 ? IEEE80211_TX_RC_80_MHZ_WIDTH : \
90 _bw == BW_40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
91 .duration = { \
92 MCS_DURATION(_streams, _sgi, \
93 BW2VBPS(_bw, 117, 54, 26)), \
94 MCS_DURATION(_streams, _sgi, \
95 BW2VBPS(_bw, 234, 108, 52)), \
96 MCS_DURATION(_streams, _sgi, \
97 BW2VBPS(_bw, 351, 162, 78)), \
98 MCS_DURATION(_streams, _sgi, \
99 BW2VBPS(_bw, 468, 216, 104)), \
100 MCS_DURATION(_streams, _sgi, \
101 BW2VBPS(_bw, 702, 324, 156)), \
102 MCS_DURATION(_streams, _sgi, \
103 BW2VBPS(_bw, 936, 432, 208)), \
104 MCS_DURATION(_streams, _sgi, \
105 BW2VBPS(_bw, 1053, 486, 234)), \
106 MCS_DURATION(_streams, _sgi, \
107 BW2VBPS(_bw, 1170, 540, 260)), \
108 MCS_DURATION(_streams, _sgi, \
109 BW2VBPS(_bw, 1404, 648, 312)), \
110 MCS_DURATION(_streams, _sgi, \
111 BW2VBPS(_bw, 1560, 720, 346)) \
112 } \
113}
114
a0497f9f 115#define CCK_DURATION(_bitrate, _short, _len) \
ed97a13c 116 (1000 * (10 /* SIFS */ + \
f359d3fe 117 (_short ? 72 + 24 : 144 + 48) + \
ed97a13c 118 (8 * (_len + 4) * 10) / (_bitrate)))
a0497f9f
FF		 119
120#define CCK_ACK_DURATION(_bitrate, _short) \
121 (CCK_DURATION((_bitrate > 10 ? 20 : 10), false, 60) + \
122 CCK_DURATION(_bitrate, _short, AVG_PKT_SIZE))
123
124#define CCK_DURATION_LIST(_short) \
125 CCK_ACK_DURATION(10, _short), \
126 CCK_ACK_DURATION(20, _short), \
127 CCK_ACK_DURATION(55, _short), \
128 CCK_ACK_DURATION(110, _short)
129
8a0ee4fe
KB		 130#define CCK_GROUP \
131 [MINSTREL_CCK_GROUP] = { \
132 .streams = 0, \
3ec373c4 133 .flags = 0, \
8a0ee4fe
KB		 134 .duration = { \
135 CCK_DURATION_LIST(false), \
136 CCK_DURATION_LIST(true) \
137 } \
a0497f9f
FF		 138 }
139
9208247d
KB		 140#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
141static bool minstrel_vht_only = true;
142module_param(minstrel_vht_only, bool, 0644);
143MODULE_PARM_DESC(minstrel_vht_only,
144 "Use only VHT rates when VHT is supported by sta.");
145#endif
146
ec8aa669
FF		 147/*
148 * To enable sufficiently targeted rate sampling, MCS rates are divided into
149 * groups, based on the number of streams and flags (HT40, SGI) that they
150 * use.
a5f69d94
HS		 151 *
152 * Sortorder has to be fixed for GROUP_IDX macro to be applicable:
8a0ee4fe 153 * BW -> SGI -> #streams
ec8aa669
FF		 154 */
155const struct mcs_group minstrel_mcs_groups[] = {
8a0ee4fe
KB		 156 MCS_GROUP(1, 0, BW_20),
157 MCS_GROUP(2, 0, BW_20),
8a0ee4fe 158 MCS_GROUP(3, 0, BW_20),
ec8aa669 159
8a0ee4fe
KB		 160 MCS_GROUP(1, 1, BW_20),
161 MCS_GROUP(2, 1, BW_20),
8a0ee4fe 162 MCS_GROUP(3, 1, BW_20),
ec8aa669 163
8a0ee4fe
KB		 164 MCS_GROUP(1, 0, BW_40),
165 MCS_GROUP(2, 0, BW_40),
8a0ee4fe 166 MCS_GROUP(3, 0, BW_40),
ec8aa669 167
8a0ee4fe
KB		 168 MCS_GROUP(1, 1, BW_40),
169 MCS_GROUP(2, 1, BW_40),
8a0ee4fe 170 MCS_GROUP(3, 1, BW_40),
a0497f9f 171
9208247d
KB		 172 CCK_GROUP,
173
174#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
175 VHT_GROUP(1, 0, BW_20),
176 VHT_GROUP(2, 0, BW_20),
9208247d 177 VHT_GROUP(3, 0, BW_20),
9208247d
KB		 178
179 VHT_GROUP(1, 1, BW_20),
180 VHT_GROUP(2, 1, BW_20),
9208247d 181 VHT_GROUP(3, 1, BW_20),
ec8aa669 182
9208247d
KB		 183 VHT_GROUP(1, 0, BW_40),
184 VHT_GROUP(2, 0, BW_40),
9208247d 185 VHT_GROUP(3, 0, BW_40),
9208247d
KB		 186
187 VHT_GROUP(1, 1, BW_40),
188 VHT_GROUP(2, 1, BW_40),
9208247d 189 VHT_GROUP(3, 1, BW_40),
9208247d
KB		 190
191 VHT_GROUP(1, 0, BW_80),
192 VHT_GROUP(2, 0, BW_80),
9208247d 193 VHT_GROUP(3, 0, BW_80),
9208247d
KB		 194
195 VHT_GROUP(1, 1, BW_80),
196 VHT_GROUP(2, 1, BW_80),
9208247d
KB		 197 VHT_GROUP(3, 1, BW_80),
198#endif
9208247d 199};
a0497f9f 200
f6e1a73b 201static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
ec8aa669 202
a8566662
FF		 203static void
204minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi);
205
9208247d
KB		 206/*
207 * Some VHT MCSes are invalid (when Ndbps / Nes is not an integer)
208 * e.g for MCS9@20MHzx1Nss: Ndbps=8x52*(5/6) Nes=1
209 *
210 * Returns the valid mcs map for struct minstrel_mcs_group_data.supported
211 */
212static u16
213minstrel_get_valid_vht_rates(int bw, int nss, __le16 mcs_map)
214{
215 u16 mask = 0;
216
217 if (bw == BW_20) {
218 if (nss != 3 && nss != 6)
219 mask = BIT(9);
220 } else if (bw == BW_80) {
221 if (nss == 3 || nss == 7)
222 mask = BIT(6);
223 else if (nss == 6)
224 mask = BIT(9);
225 } else {
226 WARN_ON(bw != BW_40);
227 }
228
229 switch ((le16_to_cpu(mcs_map) >> (2 * (nss - 1))) & 3) {
230 case IEEE80211_VHT_MCS_SUPPORT_0_7:
231 mask |= 0x300;
232 break;
233 case IEEE80211_VHT_MCS_SUPPORT_0_8:
234 mask |= 0x200;
235 break;
236 case IEEE80211_VHT_MCS_SUPPORT_0_9:
237 break;
238 default:
239 mask = 0x3ff;
240 }
241
242 return 0x3ff & ~mask;
243}
244
ec8aa669
FF		 245/*
246 * Look up an MCS group index based on mac80211 rate information
247 */
248static int
249minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate)
250{
cc61d8df 251 return GROUP_IDX((rate->idx / 8) + 1,
a5f69d94
HS		 252 !!(rate->flags & IEEE80211_TX_RC_SHORT_GI),
253 !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH));
ec8aa669
FF		 254}
255
9208247d
KB		 256static int
257minstrel_vht_get_group_idx(struct ieee80211_tx_rate *rate)
258{
259 return VHT_GROUP_IDX(ieee80211_rate_get_vht_nss(rate),
260 !!(rate->flags & IEEE80211_TX_RC_SHORT_GI),
261 !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) +
262 2*!!(rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH));
263}
264
a0497f9f
FF		 265static struct minstrel_rate_stats *
266minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
267 struct ieee80211_tx_rate *rate)
268{
269 int group, idx;
270
271 if (rate->flags & IEEE80211_TX_RC_MCS) {
272 group = minstrel_ht_get_group_idx(rate);
7a5e3fa2 273 idx = rate->idx % 8;
9208247d
KB		 274 } else if (rate->flags & IEEE80211_TX_RC_VHT_MCS) {
275 group = minstrel_vht_get_group_idx(rate);
276 idx = ieee80211_rate_get_vht_mcs(rate);
a0497f9f
FF		 277 } else {
278 group = MINSTREL_CCK_GROUP;
279
280 for (idx = 0; idx < ARRAY_SIZE(mp->cck_rates); idx++)
281 if (rate->idx == mp->cck_rates[idx])
282 break;
283
284 /* short preamble */
41d08583 285 if (!(mi->supported[group] & BIT(idx)))
a0497f9f
FF		 286 idx += 4;
287 }
288 return &mi->groups[group].rates[idx];
289}
290
ec8aa669
FF		 291static inline struct minstrel_rate_stats *
292minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index)
293{
294 return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
295}
296
ec8aa669 297/*
6a27b2c4
TH		 298 * Return current throughput based on the average A-MPDU length, taking into
299 * account the expected number of retransmissions and their expected length
ec8aa669 300 */
6a27b2c4 301int
50e55a8e
TH		 302minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate,
303 int prob_ewma)
ec8aa669 304{
ed97a13c 305 unsigned int nsecs = 0;
ec8aa669 306
9134073b 307 /* do not account throughput if sucess prob is below 10% */
50e55a8e 308 if (prob_ewma < MINSTREL_FRAC(10, 100))
6a27b2c4 309 return 0;
ec8aa669 310
a0497f9f 311 if (group != MINSTREL_CCK_GROUP)
ed97a13c 312 nsecs = 1000 * mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
a0497f9f 313
ed97a13c 314 nsecs += minstrel_mcs_groups[group].duration[rate];
ed97a13c 315
50e55a8e
TH		 316 /*
317 * For the throughput calculation, limit the probability value to 90% to
318 * account for collision related packet error rate fluctuation
319 * (prob is scaled - see MINSTREL_FRAC above)
320 */
321 if (prob_ewma > MINSTREL_FRAC(90, 100))
322 return MINSTREL_TRUNC(100000 * ((MINSTREL_FRAC(90, 100) * 1000)
323 / nsecs));
324 else
325 return MINSTREL_TRUNC(100000 * ((prob_ewma * 1000) / nsecs));
ec8aa669
FF		 326}
327
5935839a
TH		 328/*
329 * Find & sort topmost throughput rates
330 *
331 * If multiple rates provide equal throughput the sorting is based on their
332 * current success probability. Higher success probability is preferred among
333 * MCS groups, CCK rates do not provide aggregation and are therefore at last.
334 */
335static void
d4d141ca
KB		 336minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index,
337 u16 *tp_list)
5935839a 338{
6a27b2c4
TH		 339 int cur_group, cur_idx, cur_tp_avg, cur_prob;
340 int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
5935839a
TH		 341 int j = MAX_THR_RATES;
342
343 cur_group = index / MCS_GROUP_RATES;
344 cur_idx = index % MCS_GROUP_RATES;
9134073b 345 cur_prob = mi->groups[cur_group].rates[cur_idx].prob_ewma;
50e55a8e 346 cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, cur_prob);
5935839a 347
280ba51d 348 do {
5935839a
TH		 349 tmp_group = tp_list[j - 1] / MCS_GROUP_RATES;
350 tmp_idx = tp_list[j - 1] % MCS_GROUP_RATES;
9134073b 351 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
50e55a8e
TH		 352 tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx,
353 tmp_prob);
6a27b2c4
TH		 354 if (cur_tp_avg < tmp_tp_avg ||
355 (cur_tp_avg == tmp_tp_avg && cur_prob <= tmp_prob))
280ba51d
FF		 356 break;
357 j--;
358 } while (j > 0);
5935839a
TH		 359
360 if (j < MAX_THR_RATES - 1) {
361 memmove(&tp_list[j + 1], &tp_list[j], (sizeof(*tp_list) *
362 (MAX_THR_RATES - (j + 1))));
363 }
364 if (j < MAX_THR_RATES)
365 tp_list[j] = index;
366}
367
368/*
369 * Find and set the topmost probability rate per sta and per group
370 */
371static void
d4d141ca 372minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index)
5935839a
TH		 373{
374 struct minstrel_mcs_group_data *mg;
9134073b 375 struct minstrel_rate_stats *mrs;
6a27b2c4
TH		 376 int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
377 int max_tp_group, cur_tp_avg, cur_group, cur_idx;
50e55a8e
TH		 378 int max_gpr_group, max_gpr_idx;
379 int max_gpr_tp_avg, max_gpr_prob;
5935839a 380
6a27b2c4
TH		 381 cur_group = index / MCS_GROUP_RATES;
382 cur_idx = index % MCS_GROUP_RATES;
5935839a 383 mg = &mi->groups[index / MCS_GROUP_RATES];
9134073b 384 mrs = &mg->rates[index % MCS_GROUP_RATES];
5935839a
TH		 385
386 tmp_group = mi->max_prob_rate / MCS_GROUP_RATES;
387 tmp_idx = mi->max_prob_rate % MCS_GROUP_RATES;
9134073b 388 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
50e55a8e 389 tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
5935839a
TH		 390
391 /* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from
392 * MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */
393 max_tp_group = mi->max_tp_rate[0] / MCS_GROUP_RATES;
394 if((index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) &&
395 (max_tp_group != MINSTREL_CCK_GROUP))
396 return;
397
f84a9372
KK		 398 max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES;
399 max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
400 max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_ewma;
401
9134073b 402 if (mrs->prob_ewma > MINSTREL_FRAC(75, 100)) {
50e55a8e
TH		 403 cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx,
404 mrs->prob_ewma);
6a27b2c4 405 if (cur_tp_avg > tmp_tp_avg)
5935839a 406 mi->max_prob_rate = index;
6a27b2c4 407
50e55a8e
TH		 408 max_gpr_tp_avg = minstrel_ht_get_tp_avg(mi, max_gpr_group,
409 max_gpr_idx,
410 max_gpr_prob);
411 if (cur_tp_avg > max_gpr_tp_avg)
5935839a
TH		 412 mg->max_group_prob_rate = index;
413 } else {
9134073b 414 if (mrs->prob_ewma > tmp_prob)
5935839a 415 mi->max_prob_rate = index;
f84a9372 416 if (mrs->prob_ewma > max_gpr_prob)
5935839a
TH		 417 mg->max_group_prob_rate = index;
418 }
419}
420
421
422/*
423 * Assign new rate set per sta and use CCK rates only if the fastest
424 * rate (max_tp_rate[0]) is from CCK group. This prohibits such sorted
425 * rate sets where MCS and CCK rates are mixed, because CCK rates can
426 * not use aggregation.
427 */
428static void
429minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi,
d4d141ca
KB		 430 u16 tmp_mcs_tp_rate[MAX_THR_RATES],
431 u16 tmp_cck_tp_rate[MAX_THR_RATES])
5935839a 432{
50e55a8e 433 unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob;
5935839a
TH		 434 int i;
435
436 tmp_group = tmp_cck_tp_rate[0] / MCS_GROUP_RATES;
437 tmp_idx = tmp_cck_tp_rate[0] % MCS_GROUP_RATES;
50e55a8e
TH		 438 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
439 tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
5935839a
TH		 440
441 tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES;
442 tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES;
50e55a8e
TH		 443 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
444 tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
5935839a
TH		 445
446 if (tmp_cck_tp > tmp_mcs_tp) {
447 for(i = 0; i < MAX_THR_RATES; i++) {
448 minstrel_ht_sort_best_tp_rates(mi, tmp_cck_tp_rate[i],
449 tmp_mcs_tp_rate);
450 }
451 }
452
453}
454
455/*
456 * Try to increase robustness of max_prob rate by decrease number of
457 * streams if possible.
458 */
459static inline void
460minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
461{
462 struct minstrel_mcs_group_data *mg;
50e55a8e 463 int tmp_max_streams, group, tmp_idx, tmp_prob;
5935839a
TH		 464 int tmp_tp = 0;
465
466 tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] /
467 MCS_GROUP_RATES].streams;
468 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
469 mg = &mi->groups[group];
41d08583 470 if (!mi->supported[group] || group == MINSTREL_CCK_GROUP)
5935839a 471 continue;
6a27b2c4
TH		 472
473 tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
50e55a8e 474 tmp_prob = mi->groups[group].rates[tmp_idx].prob_ewma;
6a27b2c4 475
50e55a8e 476 if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) &&
5935839a
TH		 477 (minstrel_mcs_groups[group].streams < tmp_max_streams)) {
478 mi->max_prob_rate = mg->max_group_prob_rate;
6a27b2c4 479 tmp_tp = minstrel_ht_get_tp_avg(mi, group,
50e55a8e
TH		 480 tmp_idx,
481 tmp_prob);
5935839a
TH		 482 }
483 }
484}
485
ec8aa669
FF		 486/*
487 * Update rate statistics and select new primary rates
488 *
489 * Rules for rate selection:
490 * - max_prob_rate must use only one stream, as a tradeoff between delivery
491 * probability and throughput during strong fluctuations
5935839a 492 * - as long as the max prob rate has a probability of more than 75%, pick
ec8aa669
FF		 493 * higher throughput rates, even if the probablity is a bit lower
494 */
495static void
496minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
497{
498 struct minstrel_mcs_group_data *mg;
9134073b 499 struct minstrel_rate_stats *mrs;
50e55a8e 500 int group, i, j, cur_prob;
d4d141ca
KB		 501 u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES];
502 u16 tmp_cck_tp_rate[MAX_THR_RATES], index;
ec8aa669
FF		 503
504 if (mi->ampdu_packets > 0) {
505 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
506 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL);
507 mi->ampdu_len = 0;
508 mi->ampdu_packets = 0;
509 }
510
511 mi->sample_slow = 0;
512 mi->sample_count = 0;
ec8aa669 513
5935839a
TH		 514 /* Initialize global rate indexes */
515 for(j = 0; j < MAX_THR_RATES; j++){
516 tmp_mcs_tp_rate[j] = 0;
517 tmp_cck_tp_rate[j] = 0;
518 }
c2eb5b0f 519
5935839a
TH		 520 /* Find best rate sets within all MCS groups*/
521 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
ec8aa669
FF		 522
523 mg = &mi->groups[group];
41d08583 524 if (!mi->supported[group])
ec8aa669
FF		 525 continue;
526
ec8aa669
FF		 527 mi->sample_count++;
528
5935839a
TH		 529 /* (re)Initialize group rate indexes */
530 for(j = 0; j < MAX_THR_RATES; j++)
531 tmp_group_tp_rate[j] = group;
532
ec8aa669 533 for (i = 0; i < MCS_GROUP_RATES; i++) {
41d08583 534 if (!(mi->supported[group] & BIT(i)))
ec8aa669
FF		 535 continue;
536
351df099
KB		 537 index = MCS_GROUP_RATES * group + i;
538
9134073b
TH		 539 mrs = &mg->rates[i];
540 mrs->retry_updated = false;
541 minstrel_calc_rate_stats(mrs);
50e55a8e 542 cur_prob = mrs->prob_ewma;
ec8aa669 543
50e55a8e 544 if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0)
ec8aa669
FF		 545 continue;
546
5935839a
TH		 547 /* Find max throughput rate set */
548 if (group != MINSTREL_CCK_GROUP) {
549 minstrel_ht_sort_best_tp_rates(mi, index,
550 tmp_mcs_tp_rate);
551 } else if (group == MINSTREL_CCK_GROUP) {
552 minstrel_ht_sort_best_tp_rates(mi, index,
553 tmp_cck_tp_rate);
ec8aa669 554 }
ec8aa669 555
5935839a
TH		 556 /* Find max throughput rate set within a group */
557 minstrel_ht_sort_best_tp_rates(mi, index,
558 tmp_group_tp_rate);
ec8aa669 559
5935839a
TH		 560 /* Find max probability rate per group and global */
561 minstrel_ht_set_best_prob_rate(mi, index);
ec8aa669
FF		 562 }
563
5935839a
TH		 564 memcpy(mg->max_group_tp_rate, tmp_group_tp_rate,
565 sizeof(mg->max_group_tp_rate));
ec8aa669
FF		 566 }
567
5935839a
TH		 568 /* Assign new rate set per sta */
569 minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, tmp_cck_tp_rate);
570 memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate));
a299c6d5 571
5935839a
TH		 572 /* Try to increase robustness of max_prob_rate*/
573 minstrel_ht_prob_rate_reduce_streams(mi);
574
575 /* try to sample all available rates during each interval */
576 mi->sample_count *= 8;
a299c6d5 577
37feb7e2
LB		 578#ifdef CONFIG_MAC80211_DEBUGFS
579 /* use fixed index if set */
580 if (mp->fixed_rate_idx != -1) {
5935839a
TH		 581 for (i = 0; i < 4; i++)
582 mi->max_tp_rate[i] = mp->fixed_rate_idx;
37feb7e2
LB		 583 mi->max_prob_rate = mp->fixed_rate_idx;
584 }
585#endif
a299c6d5 586
5935839a 587 /* Reset update timer */
9134073b 588 mi->last_stats_update = jiffies;
ec8aa669
FF		 589}
590
591static bool
a0497f9f 592minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct ieee80211_tx_rate *rate)
ec8aa669 593{
b79296be 594 if (rate->idx < 0)
ec8aa669
FF		 595 return false;
596
b79296be 597 if (!rate->count)
ec8aa669
FF		 598 return false;
599
9208247d
KB		 600 if (rate->flags & IEEE80211_TX_RC_MCS ||
601 rate->flags & IEEE80211_TX_RC_VHT_MCS)
a0497f9f
FF		 602 return true;
603
604 return rate->idx == mp->cck_rates[0] ||
605 rate->idx == mp->cck_rates[1] ||
606 rate->idx == mp->cck_rates[2] ||
607 rate->idx == mp->cck_rates[3];
ec8aa669
FF		 608}
609
610static void
9134073b 611minstrel_set_next_sample_idx(struct minstrel_ht_sta *mi)
ec8aa669
FF		 612{
613 struct minstrel_mcs_group_data *mg;
614
615 for (;;) {
616 mi->sample_group++;
617 mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
618 mg = &mi->groups[mi->sample_group];
619
41d08583 620 if (!mi->supported[mi->sample_group])
ec8aa669
FF		 621 continue;
622
623 if (++mg->index >= MCS_GROUP_RATES) {
624 mg->index = 0;
625 if (++mg->column >= ARRAY_SIZE(sample_table))
626 mg->column = 0;
627 }
628 break;
629 }
630}
631
632static void
d4d141ca 633minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary)
ec8aa669
FF		 634{
635 int group, orig_group;
636
637 orig_group = group = *idx / MCS_GROUP_RATES;
638 while (group > 0) {
639 group--;
640
41d08583 641 if (!mi->supported[group])
ec8aa669
FF		 642 continue;
643
644 if (minstrel_mcs_groups[group].streams >
645 minstrel_mcs_groups[orig_group].streams)
646 continue;
647
648 if (primary)
5935839a 649 *idx = mi->groups[group].max_group_tp_rate[0];
ec8aa669 650 else
5935839a 651 *idx = mi->groups[group].max_group_tp_rate[1];
ec8aa669
FF		 652 break;
653 }
654}
655
656static void
6048d763 657minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb)
ec8aa669
FF		 658{
659 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
660 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
661 u16 tid;
662
75769c80
FF		 663 if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO)
664 return;
665
ec8aa669
FF		 666 if (unlikely(!ieee80211_is_data_qos(hdr->frame_control)))
667 return;
668
e133fae2 669 if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE)))
ec8aa669
FF		 670 return;
671
672 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
a622ab72 673 if (likely(sta->ampdu_mlme.tid_tx[tid]))
ec8aa669
FF		 674 return;
675
7a36b930 676 ieee80211_start_tx_ba_session(pubsta, tid, 0);
ec8aa669
FF		 677}
678
679static void
680minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
681 struct ieee80211_sta *sta, void *priv_sta,
63558a65 682 struct ieee80211_tx_info *info)
ec8aa669
FF		 683{
684 struct minstrel_ht_sta_priv *msp = priv_sta;
685 struct minstrel_ht_sta *mi = &msp->ht;
ec8aa669
FF		 686 struct ieee80211_tx_rate *ar = info->status.rates;
687 struct minstrel_rate_stats *rate, *rate2;
688 struct minstrel_priv *mp = priv;
a8566662 689 bool last, update = false;
a544ab7f 690 int i;
ec8aa669
FF		 691
692 if (!msp->is_ht)
63558a65
FF		 693 return mac80211_minstrel.tx_status_noskb(priv, sband, sta,
694 &msp->legacy, info);
ec8aa669
FF		 695
696 /* This packet was aggregated but doesn't carry status info */
697 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
698 !(info->flags & IEEE80211_TX_STAT_AMPDU))
699 return;
700
15d46f38
BS		 701 if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) {
702 info->status.ampdu_ack_len =
703 (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0);
ec8aa669
FF		 704 info->status.ampdu_len = 1;
705 }
706
707 mi->ampdu_packets++;
708 mi->ampdu_len += info->status.ampdu_len;
709
710 if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
c7317e41 711 mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len);
52c00a37 712 mi->sample_tries = 1;
ec8aa669
FF		 713 mi->sample_count--;
714 }
715
8d5eab5a 716 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
ec8aa669 717 mi->sample_packets += info->status.ampdu_len;
ec8aa669 718
a0497f9f 719 last = !minstrel_ht_txstat_valid(mp, &ar[0]);
ec8aa669
FF		 720 for (i = 0; !last; i++) {
721 last = (i == IEEE80211_TX_MAX_RATES - 1) ||
a0497f9f 722 !minstrel_ht_txstat_valid(mp, &ar[i + 1]);
ec8aa669 723
a0497f9f 724 rate = minstrel_ht_get_stats(mp, mi, &ar[i]);
ec8aa669 725
15d46f38 726 if (last)
ec8aa669
FF		 727 rate->success += info->status.ampdu_ack_len;
728
729 rate->attempts += ar[i].count * info->status.ampdu_len;
730 }
731
732 /*
733 * check for sudden death of spatial multiplexing,
734 * downgrade to a lower number of streams if necessary.
735 */
5935839a 736 rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]);
ec8aa669
FF		 737 if (rate->attempts > 30 &&
738 MINSTREL_FRAC(rate->success, rate->attempts) <
a8566662 739 MINSTREL_FRAC(20, 100)) {
5935839a 740 minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true);
a8566662
FF		 741 update = true;
742 }
ec8aa669 743
5935839a 744 rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]);
ecc3d5ae
ML		 745 if (rate2->attempts > 30 &&
746 MINSTREL_FRAC(rate2->success, rate2->attempts) <
a8566662 747 MINSTREL_FRAC(20, 100)) {
5935839a 748 minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false);
a8566662
FF		 749 update = true;
750 }
ec8aa669 751
9134073b
TH		 752 if (time_after(jiffies, mi->last_stats_update +
753 (mp->update_interval / 2 * HZ) / 1000)) {
a8566662 754 update = true;
ec8aa669 755 minstrel_ht_update_stats(mp, mi);
ec8aa669 756 }
a8566662
FF		 757
758 if (update)
759 minstrel_ht_update_rates(mp, mi);
ec8aa669
FF		 760}
761
762static void
763minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
764 int index)
765{
9134073b 766 struct minstrel_rate_stats *mrs;
ec8aa669
FF		 767 const struct mcs_group *group;
768 unsigned int tx_time, tx_time_rtscts, tx_time_data;
769 unsigned int cw = mp->cw_min;
8fddddff 770 unsigned int ctime = 0;
ec8aa669
FF		 771 unsigned int t_slot = 9; /* FIXME */
772 unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len);
a0497f9f 773 unsigned int overhead = 0, overhead_rtscts = 0;
ec8aa669 774
9134073b
TH		 775 mrs = minstrel_get_ratestats(mi, index);
776 if (mrs->prob_ewma < MINSTREL_FRAC(1, 10)) {
777 mrs->retry_count = 1;
778 mrs->retry_count_rtscts = 1;
ec8aa669
FF		 779 return;
780 }
781
9134073b
TH		 782 mrs->retry_count = 2;
783 mrs->retry_count_rtscts = 2;
784 mrs->retry_updated = true;
ec8aa669
FF		 785
786 group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
ed97a13c 787 tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len / 1000;
8fddddff
DH		 788
789 /* Contention time for first 2 tries */
790 ctime = (t_slot * cw) >> 1;
791 cw = min((cw << 1) | 1, mp->cw_max);
792 ctime += (t_slot * cw) >> 1;
793 cw = min((cw << 1) | 1, mp->cw_max);
794
a0497f9f
FF		 795 if (index / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) {
796 overhead = mi->overhead;
797 overhead_rtscts = mi->overhead_rtscts;
798 }
799
8fddddff 800 /* Total TX time for data and Contention after first 2 tries */
a0497f9f
FF		 801 tx_time = ctime + 2 * (overhead + tx_time_data);
802 tx_time_rtscts = ctime + 2 * (overhead_rtscts + tx_time_data);
8fddddff
DH		 803
804 /* See how many more tries we can fit inside segment size */
ec8aa669 805 do {
8fddddff
DH		 806 /* Contention time for this try */
807 ctime = (t_slot * cw) >> 1;
808 cw = min((cw << 1) | 1, mp->cw_max);
809
810 /* Total TX time after this try */
a0497f9f
FF		 811 tx_time += ctime + overhead + tx_time_data;
812 tx_time_rtscts += ctime + overhead_rtscts + tx_time_data;
8fddddff 813
ec8aa669 814 if (tx_time_rtscts < mp->segment_size)
9134073b 815 mrs->retry_count_rtscts++;
ec8aa669 816 } while ((tx_time < mp->segment_size) &&
9134073b 817 (++mrs->retry_count < mp->max_retry));
ec8aa669
FF		 818}
819
820
821static void
822minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
a8566662 823 struct ieee80211_sta_rates *ratetbl, int offset, int index)
ec8aa669
FF		 824{
825 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
9134073b 826 struct minstrel_rate_stats *mrs;
a8566662 827 u8 idx;
3ec373c4 828 u16 flags = group->flags;
ec8aa669 829
9134073b
TH		 830 mrs = minstrel_get_ratestats(mi, index);
831 if (!mrs->retry_updated)
ec8aa669
FF		 832 minstrel_calc_retransmit(mp, mi, index);
833
9134073b 834 if (mrs->prob_ewma < MINSTREL_FRAC(20, 100) || !mrs->retry_count) {
a8566662
FF		 835 ratetbl->rate[offset].count = 2;
836 ratetbl->rate[offset].count_rts = 2;
837 ratetbl->rate[offset].count_cts = 2;
838 } else {
9134073b
TH		 839 ratetbl->rate[offset].count = mrs->retry_count;
840 ratetbl->rate[offset].count_cts = mrs->retry_count;
841 ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts;
a8566662 842 }
a0497f9f 843
3ec373c4 844 if (index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP)
a8566662 845 idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)];
9208247d
KB		 846 else if (flags & IEEE80211_TX_RC_VHT_MCS)
847 idx = ((group->streams - 1) << 4) |
848 ((index % MCS_GROUP_RATES) & 0xF);
3ec373c4 849 else
7a5e3fa2 850 idx = index % MCS_GROUP_RATES + (group->streams - 1) * 8;
a8566662 851
a3ebb4e1
KC		 852 /* enable RTS/CTS if needed:
853 * - if station is in dynamic SMPS (and streams > 1)
854 * - for fallback rates, to increase chances of getting through
855 */
c36dd3ea 856 if (offset > 0 ||
a3ebb4e1
KC		 857 (mi->sta->smps_mode == IEEE80211_SMPS_DYNAMIC &&
858 group->streams > 1)) {
a8566662
FF		 859 ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts;
860 flags |= IEEE80211_TX_RC_USE_RTS_CTS;
861 }
862
863 ratetbl->rate[offset].idx = idx;
864 ratetbl->rate[offset].flags = flags;
865}
866
918fe04b
FF		 867static inline int
868minstrel_ht_get_prob_ewma(struct minstrel_ht_sta *mi, int rate)
869{
870 int group = rate / MCS_GROUP_RATES;
871 rate %= MCS_GROUP_RATES;
872 return mi->groups[group].rates[rate].prob_ewma;
873}
874
875static int
876minstrel_ht_get_max_amsdu_len(struct minstrel_ht_sta *mi)
877{
878 int group = mi->max_prob_rate / MCS_GROUP_RATES;
879 const struct mcs_group *g = &minstrel_mcs_groups[group];
880 int rate = mi->max_prob_rate % MCS_GROUP_RATES;
881
882 /* Disable A-MSDU if max_prob_rate is bad */
883 if (mi->groups[group].rates[rate].prob_ewma < MINSTREL_FRAC(50, 100))
884 return 1;
885
886 /* If the rate is slower than single-stream MCS1, make A-MSDU limit small */
887 if (g->duration[rate] > MCS_DURATION(1, 0, 52))
888 return 500;
889
890 /*
891 * If the rate is slower than single-stream MCS4, limit A-MSDU to usual
892 * data packet size
893 */
894 if (g->duration[rate] > MCS_DURATION(1, 0, 104))
895 return 1600;
896
897 /*
898 * If the rate is slower than single-stream MCS7, or if the max throughput
899 * rate success probability is less than 75%, limit A-MSDU to twice the usual
900 * data packet size
901 */
902 if (g->duration[rate] > MCS_DURATION(1, 0, 260) ||
903 (minstrel_ht_get_prob_ewma(mi, mi->max_tp_rate[0]) <
904 MINSTREL_FRAC(75, 100)))
905 return 3200;
906
907 /*
908 * HT A-MPDU limits maximum MPDU size under BA agreement to 4095 bytes.
909 * Since aggregation sessions are started/stopped without txq flush, use
910 * the limit here to avoid the complexity of having to de-aggregate
911 * packets in the queue.
912 */
913 if (!mi->sta->vht_cap.vht_supported)
914 return IEEE80211_MAX_MPDU_LEN_HT_BA;
915
916 /* unlimited */
917 return 0;
918}
919
a8566662
FF		 920static void
921minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
922{
923 struct ieee80211_sta_rates *rates;
924 int i = 0;
925
926 rates = kzalloc(sizeof(*rates), GFP_ATOMIC);
927 if (!rates)
a0497f9f 928 return;
a8566662 929
5935839a
TH		 930 /* Start with max_tp_rate[0] */
931 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]);
a8566662
FF		 932
933 if (mp->hw->max_rates >= 3) {
5935839a
TH		 934 /* At least 3 tx rates supported, use max_tp_rate[1] next */
935 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]);
a8566662
FF		 936 }
937
938 if (mp->hw->max_rates >= 2) {
939 /*
940 * At least 2 tx rates supported, use max_prob_rate next */
941 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate);
a0497f9f
FF		 942 }
943
918fe04b 944 mi->sta->max_rc_amsdu_len = minstrel_ht_get_max_amsdu_len(mi);
a8566662
FF		 945 rates->rate[i].idx = -1;
946 rate_control_set_rates(mp->hw, mi->sta, rates);
ec8aa669
FF		 947}
948
949static inline int
950minstrel_get_duration(int index)
951{
952 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
953 return group->duration[index % MCS_GROUP_RATES];
954}
955
956static int
957minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
958{
9134073b 959 struct minstrel_rate_stats *mrs;
ec8aa669 960 struct minstrel_mcs_group_data *mg;
5935839a 961 unsigned int sample_dur, sample_group, cur_max_tp_streams;
06171e9c 962 int tp_rate1, tp_rate2;
ec8aa669
FF		 963 int sample_idx = 0;
964
965 if (mi->sample_wait > 0) {
966 mi->sample_wait--;
967 return -1;
968 }
969
970 if (!mi->sample_tries)
971 return -1;
972
f12140c0
KB		 973 sample_group = mi->sample_group;
974 mg = &mi->groups[sample_group];
ec8aa669 975 sample_idx = sample_table[mg->column][mg->index];
9134073b 976 minstrel_set_next_sample_idx(mi);
f12140c0 977
41d08583 978 if (!(mi->supported[sample_group] & BIT(sample_idx)))
f12140c0
KB		 979 return -1;
980
9134073b 981 mrs = &mg->rates[sample_idx];
965237ab 982 sample_idx += sample_group * MCS_GROUP_RATES;
ec8aa669 983
06171e9c
FF		 984 /* Set tp_rate1, tp_rate2 to the highest / second highest max_tp_rate */
985 if (minstrel_get_duration(mi->max_tp_rate[0]) >
986 minstrel_get_duration(mi->max_tp_rate[1])) {
987 tp_rate1 = mi->max_tp_rate[1];
988 tp_rate2 = mi->max_tp_rate[0];
989 } else {
990 tp_rate1 = mi->max_tp_rate[0];
991 tp_rate2 = mi->max_tp_rate[1];
992 }
993
ba6fa29c
HS		 994 /*
995 * Sampling might add some overhead (RTS, no aggregation)
06171e9c
FF		 996 * to the frame. Hence, don't use sampling for the highest currently
997 * used highest throughput or probability rate.
ba6fa29c 998 */
06171e9c 999 if (sample_idx == mi->max_tp_rate[0] || sample_idx == mi->max_prob_rate)
ba6fa29c 1000 return -1;
a0ca796c 1001
ec8aa669 1002 /*
bc96f242
FF		 1003 * Do not sample if the probability is already higher than 95%
1004 * to avoid wasting airtime.
ec8aa669 1005 */
9134073b 1006 if (mrs->prob_ewma > MINSTREL_FRAC(95, 100))
8d5eab5a 1007 return -1;
ec8aa669
FF		 1008
1009 /*
1010 * Make sure that lower rates get sampled only occasionally,
1011 * if the link is working perfectly.
1012 */
5935839a 1013
06171e9c 1014 cur_max_tp_streams = minstrel_mcs_groups[tp_rate1 /
5935839a 1015 MCS_GROUP_RATES].streams;
965237ab 1016 sample_dur = minstrel_get_duration(sample_idx);
06171e9c 1017 if (sample_dur >= minstrel_get_duration(tp_rate2) &&
5935839a 1018 (cur_max_tp_streams - 1 <
965237ab
FF		 1019 minstrel_mcs_groups[sample_group].streams ||
1020 sample_dur >= minstrel_get_duration(mi->max_prob_rate))) {
9134073b 1021 if (mrs->sample_skipped < 20)
8d5eab5a 1022 return -1;
ec8aa669
FF		 1023
1024 if (mi->sample_slow++ > 2)
8d5eab5a 1025 return -1;
ec8aa669 1026 }
098b8afb 1027 mi->sample_tries--;
ec8aa669
FF		 1028
1029 return sample_idx;
ec8aa669
FF		 1030}
1031
1032static void
1033minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
1034 struct ieee80211_tx_rate_control *txrc)
1035{
a8566662 1036 const struct mcs_group *sample_group;
ec8aa669 1037 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
a8566662 1038 struct ieee80211_tx_rate *rate = &info->status.rates[0];
ec8aa669
FF		 1039 struct minstrel_ht_sta_priv *msp = priv_sta;
1040 struct minstrel_ht_sta *mi = &msp->ht;
1041 struct minstrel_priv *mp = priv;
1042 int sample_idx;
1043
1044 if (rate_control_send_low(sta, priv_sta, txrc))
1045 return;
1046
1047 if (!msp->is_ht)
1048 return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc);
1049
95943425
FF		 1050 if (!(info->flags & IEEE80211_TX_CTL_AMPDU) &&
1051 mi->max_prob_rate / MCS_GROUP_RATES != MINSTREL_CCK_GROUP)
1052 minstrel_aggr_check(sta, txrc->skb);
1053
ec8aa669 1054 info->flags |= mi->tx_flags;
6de062ce 1055
37feb7e2
LB		 1056#ifdef CONFIG_MAC80211_DEBUGFS
1057 if (mp->fixed_rate_idx != -1)
1058 return;
1059#endif
1060
6de062ce
HS		 1061 /* Don't use EAPOL frames for sampling on non-mrr hw */
1062 if (mp->hw->max_rates == 1 &&
af61a165 1063 (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO))
6de062ce
HS		 1064 sample_idx = -1;
1065 else
1066 sample_idx = minstrel_get_sample_rate(mp, mi);
24f7580e 1067
ec8aa669
FF		 1068 mi->total_packets++;
1069
1070 /* wraparound */
1071 if (mi->total_packets == ~0) {
1072 mi->total_packets = 0;
1073 mi->sample_packets = 0;
1074 }
a8566662
FF		 1075
1076 if (sample_idx < 0)
1077 return;
1078
1079 sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES];
1080 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
1cd15857
FF		 1081 rate->count = 1;
1082
1083 if (sample_idx / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) {
1084 int idx = sample_idx % ARRAY_SIZE(mp->cck_rates);
1085 rate->idx = mp->cck_rates[idx];
9208247d
KB		 1086 } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) {
1087 ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES,
1088 sample_group->streams);
3ec373c4
KB		 1089 } else {
1090 rate->idx = sample_idx % MCS_GROUP_RATES +
1091 (sample_group->streams - 1) * 8;
1cd15857
FF		 1092 }
1093
3ec373c4 1094 rate->flags = sample_group->flags;
ec8aa669
FF		 1095}
1096
a0497f9f
FF		 1097static void
1098minstrel_ht_update_cck(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
1099 struct ieee80211_supported_band *sband,
1100 struct ieee80211_sta *sta)
1101{
1102 int i;
1103
57fbcce3 1104 if (sband->band != NL80211_BAND_2GHZ)
a0497f9f
FF		 1105 return;
1106
30686bf7 1107 if (!ieee80211_hw_check(mp->hw, SUPPORTS_HT_CCK_RATES))
2dfca312
FF		 1108 return;
1109
a0497f9f
FF		 1110 mi->cck_supported = 0;
1111 mi->cck_supported_short = 0;
1112 for (i = 0; i < 4; i++) {
1113 if (!rate_supported(sta, sband->band, mp->cck_rates[i]))
1114 continue;
1115
1116 mi->cck_supported |= BIT(i);
1117 if (sband->bitrates[i].flags & IEEE80211_RATE_SHORT_PREAMBLE)
1118 mi->cck_supported_short |= BIT(i);
1119 }
1120
41d08583 1121 mi->supported[MINSTREL_CCK_GROUP] = mi->cck_supported;
a0497f9f
FF		 1122}
1123
ec8aa669
FF		 1124static void
1125minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
3de805cf 1126 struct cfg80211_chan_def *chandef,
64f68e5d 1127 struct ieee80211_sta *sta, void *priv_sta)
ec8aa669
FF		 1128{
1129 struct minstrel_priv *mp = priv;
1130 struct minstrel_ht_sta_priv *msp = priv_sta;
1131 struct minstrel_ht_sta *mi = &msp->ht;
1132 struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
ec8aa669 1133 u16 sta_cap = sta->ht_cap.cap;
9208247d 1134 struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
782dda00 1135 struct sta_info *sinfo = container_of(sta, struct sta_info, sta);
9208247d 1136 int use_vht;
4dc217df 1137 int n_supported = 0;
ec8aa669
FF		 1138 int ack_dur;
1139 int stbc;
1140 int i;
1141
1142 /* fall back to the old minstrel for legacy stations */
4dc217df
FF		 1143 if (!sta->ht_cap.ht_supported)
1144 goto use_legacy;
ec8aa669 1145
8a0ee4fe 1146 BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB);
ec8aa669 1147
9208247d
KB		 1148#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
1149 if (vht_cap->vht_supported)
1150 use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0);
1151 else
1152#endif
1153 use_vht = 0;
1154
ec8aa669
FF		 1155 msp->is_ht = true;
1156 memset(mi, 0, sizeof(*mi));
a8566662
FF		 1157
1158 mi->sta = sta;
9134073b 1159 mi->last_stats_update = jiffies;
ec8aa669 1160
438b61b7
SW		 1161 ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1, 0);
1162 mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1, 0);
1163 mi->overhead += ack_dur;
ec8aa669
FF		 1164 mi->overhead_rtscts = mi->overhead + 2 * ack_dur;
1165
1166 mi->avg_ampdu_len = MINSTREL_FRAC(1, 1);
1167
1168 /* When using MRR, sample more on the first attempt, without delay */
1169 if (mp->has_mrr) {
1170 mi->sample_count = 16;
1171 mi->sample_wait = 0;
1172 } else {
1173 mi->sample_count = 8;
1174 mi->sample_wait = 8;
1175 }
1176 mi->sample_tries = 4;
1177
9208247d
KB		 1178 /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */
1179 if (!use_vht) {
1180 stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
1181 IEEE80211_HT_CAP_RX_STBC_SHIFT;
1182 mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
ec8aa669 1183
9208247d
KB		 1184 if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
1185 mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
1186 }
ec8aa669 1187
ec8aa669 1188 for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
3ec373c4 1189 u32 gflags = minstrel_mcs_groups[i].flags;
9208247d 1190 int bw, nss;
3ec373c4 1191
41d08583 1192 mi->supported[i] = 0;
a0497f9f
FF		 1193 if (i == MINSTREL_CCK_GROUP) {
1194 minstrel_ht_update_cck(mp, mi, sband, sta);
1195 continue;
1196 }
1197
3ec373c4
KB		 1198 if (gflags & IEEE80211_TX_RC_SHORT_GI) {
1199 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
e1a0c6b3
JB		 1200 if (!(sta_cap & IEEE80211_HT_CAP_SGI_40))
1201 continue;
1202 } else {
1203 if (!(sta_cap & IEEE80211_HT_CAP_SGI_20))
1204 continue;
1205 }
ec8aa669
FF		 1206 }
1207
3ec373c4 1208 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH &&
e1a0c6b3 1209 sta->bandwidth < IEEE80211_STA_RX_BW_40)
ec8aa669
FF		 1210 continue;
1211
9208247d
KB		 1212 nss = minstrel_mcs_groups[i].streams;
1213
e9219779 1214 /* Mark MCS > 7 as unsupported if STA is in static SMPS mode */
9208247d
KB		 1215 if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1)
1216 continue;
1217
1218 /* HT rate */
1219 if (gflags & IEEE80211_TX_RC_MCS) {
1220#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
9ffe9044 1221 if (use_vht && minstrel_vht_only)
9208247d
KB		 1222 continue;
1223#endif
41d08583
FF		 1224 mi->supported[i] = mcs->rx_mask[nss - 1];
1225 if (mi->supported[i])
9208247d
KB		 1226 n_supported++;
1227 continue;
1228 }
1229
1230 /* VHT rate */
1231 if (!vht_cap->vht_supported ||
1232 WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) ||
1233 WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH))
e9219779
HS		 1234 continue;
1235
9208247d
KB		 1236 if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) {
1237 if (sta->bandwidth < IEEE80211_STA_RX_BW_80 ||
1238 ((gflags & IEEE80211_TX_RC_SHORT_GI) &&
1239 !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) {
1240 continue;
1241 }
1242 }
1243
1244 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH)
1245 bw = BW_40;
1246 else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH)
1247 bw = BW_80;
1248 else
1249 bw = BW_20;
1250
41d08583 1251 mi->supported[i] = minstrel_get_valid_vht_rates(bw, nss,
9208247d 1252 vht_cap->vht_mcs.tx_mcs_map);
4dc217df 1253
41d08583 1254 if (mi->supported[i])
4dc217df 1255 n_supported++;
ec8aa669 1256 }
4dc217df
FF		 1257
1258 if (!n_supported)
1259 goto use_legacy;
1260
782dda00
FF		 1261 if (test_sta_flag(sinfo, WLAN_STA_SHORT_PREAMBLE))
1262 mi->cck_supported_short |= mi->cck_supported_short << 4;
1263
a8566662 1264 /* create an initial rate table with the lowest supported rates */
a3647362 1265 minstrel_ht_update_stats(mp, mi);
a8566662 1266 minstrel_ht_update_rates(mp, mi);
a3647362 1267
4dc217df
FF		 1268 return;
1269
1270use_legacy:
1271 msp->is_ht = false;
1272 memset(&msp->legacy, 0, sizeof(msp->legacy));
1273 msp->legacy.r = msp->ratelist;
1274 msp->legacy.sample_table = msp->sample_table;
3de805cf
SW		 1275 return mac80211_minstrel.rate_init(priv, sband, chandef, sta,
1276 &msp->legacy);
ec8aa669
FF		 1277}
1278
1279static void
1280minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband,
3de805cf 1281 struct cfg80211_chan_def *chandef,
ec8aa669
FF		 1282 struct ieee80211_sta *sta, void *priv_sta)
1283{
3de805cf 1284 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta);
ec8aa669
FF		 1285}
1286
1287static void
1288minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband,
3de805cf 1289 struct cfg80211_chan_def *chandef,
ec8aa669 1290 struct ieee80211_sta *sta, void *priv_sta,
64f68e5d 1291 u32 changed)
ec8aa669 1292{
3de805cf 1293 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta);
ec8aa669
FF		 1294}
1295
1296static void *
1297minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
1298{
1299 struct ieee80211_supported_band *sband;
1300 struct minstrel_ht_sta_priv *msp;
1301 struct minstrel_priv *mp = priv;
1302 struct ieee80211_hw *hw = mp->hw;
1303 int max_rates = 0;
1304 int i;
1305
57fbcce3 1306 for (i = 0; i < NUM_NL80211_BANDS; i++) {
ec8aa669
FF		 1307 sband = hw->wiphy->bands[i];
1308 if (sband && sband->n_bitrates > max_rates)
1309 max_rates = sband->n_bitrates;
1310 }
1311
472dd35c 1312 msp = kzalloc(sizeof(*msp), gfp);
ec8aa669
FF		 1313 if (!msp)
1314 return NULL;
1315
1316 msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp);
1317 if (!msp->ratelist)
1318 goto error;
1319
1320 msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp);
1321 if (!msp->sample_table)
1322 goto error1;
1323
1324 return msp;
1325
1326error1:
7e988014 1327 kfree(msp->ratelist);
ec8aa669
FF		 1328error:
1329 kfree(msp);
1330 return NULL;
1331}
1332
1333static void
1334minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
1335{
1336 struct minstrel_ht_sta_priv *msp = priv_sta;
1337
1338 kfree(msp->sample_table);
1339 kfree(msp->ratelist);
1340 kfree(msp);
1341}
1342
1343static void *
1344minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
1345{
1346 return mac80211_minstrel.alloc(hw, debugfsdir);
1347}
1348
1349static void
1350minstrel_ht_free(void *priv)
1351{
1352 mac80211_minstrel.free(priv);
1353}
1354
cca674d4
AQ		 1355static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
1356{
1357 struct minstrel_ht_sta_priv *msp = priv_sta;
1358 struct minstrel_ht_sta *mi = &msp->ht;
50e55a8e 1359 int i, j, prob, tp_avg;
cca674d4
AQ		 1360
1361 if (!msp->is_ht)
1362 return mac80211_minstrel.get_expected_throughput(priv_sta);
1363
5935839a
TH		 1364 i = mi->max_tp_rate[0] / MCS_GROUP_RATES;
1365 j = mi->max_tp_rate[0] % MCS_GROUP_RATES;
50e55a8e 1366 prob = mi->groups[i].rates[j].prob_ewma;
cca674d4 1367
6a27b2c4 1368 /* convert tp_avg from pkt per second in kbps */
212c5a5e
SE		 1369 tp_avg = minstrel_ht_get_tp_avg(mi, i, j, prob) * 10;
1370 tp_avg = tp_avg * AVG_PKT_SIZE * 8 / 1024;
6a27b2c4
TH		 1371
1372 return tp_avg;
cca674d4
AQ		 1373}
1374
631ad703 1375static const struct rate_control_ops mac80211_minstrel_ht = {
ec8aa669 1376 .name = "minstrel_ht",
63558a65 1377 .tx_status_noskb = minstrel_ht_tx_status,
ec8aa669
FF		 1378 .get_rate = minstrel_ht_get_rate,
1379 .rate_init = minstrel_ht_rate_init,
1380 .rate_update = minstrel_ht_rate_update,
1381 .alloc_sta = minstrel_ht_alloc_sta,
1382 .free_sta = minstrel_ht_free_sta,
1383 .alloc = minstrel_ht_alloc,
1384 .free = minstrel_ht_free,
1385#ifdef CONFIG_MAC80211_DEBUGFS
1386 .add_sta_debugfs = minstrel_ht_add_sta_debugfs,
1387 .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs,
1388#endif
cca674d4 1389 .get_expected_throughput = minstrel_ht_get_expected_throughput,
ec8aa669
FF		 1390};
1391
1392
f6e1a73b 1393static void __init init_sample_table(void)
ec8aa669
FF		 1394{
1395 int col, i, new_idx;
1396 u8 rnd[MCS_GROUP_RATES];
1397
1398 memset(sample_table, 0xff, sizeof(sample_table));
1399 for (col = 0; col < SAMPLE_COLUMNS; col++) {
f7d8ad81 1400 prandom_bytes(rnd, sizeof(rnd));
ec8aa669 1401 for (i = 0; i < MCS_GROUP_RATES; i++) {
ec8aa669 1402 new_idx = (i + rnd[i]) % MCS_GROUP_RATES;
ec8aa669
FF		 1403 while (sample_table[col][new_idx] != 0xff)
1404 new_idx = (new_idx + 1) % MCS_GROUP_RATES;
1405
1406 sample_table[col][new_idx] = i;
1407 }
1408 }
1409}
1410
1411int __init
1412rc80211_minstrel_ht_init(void)
1413{
1414 init_sample_table();
1415 return ieee80211_rate_control_register(&mac80211_minstrel_ht);
1416}
1417
1418void
1419rc80211_minstrel_ht_exit(void)
1420{
1421 ieee80211_rate_control_unregister(&mac80211_minstrel_ht);
1422}
Linux 6.x block layer and io_uring tree(s)