--- /dev/null
+/*
+ * Copyright (C) 2010-2013 Felix Fietkau <nbd@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/netdevice.h>
+#include <linux/types.h>
+#include <linux/skbuff.h>
+#include <linux/debugfs.h>
+#include <linux/random.h>
+#include <linux/moduleparam.h>
+#include <linux/ieee80211.h>
+#include <net/mac80211.h>
+#include "rate.h"
+#include "rc80211_minstrel.h"
+#include "rc80211_minstrel_ht.h"
+
+#define AVG_AMPDU_SIZE 16
+#define AVG_PKT_SIZE 1200
+
+/* Number of bits for an average sized packet */
+#define MCS_NBITS ((AVG_PKT_SIZE * AVG_AMPDU_SIZE) << 3)
+
+/* Number of symbols for a packet with (bps) bits per symbol */
+#define MCS_NSYMS(bps) DIV_ROUND_UP(MCS_NBITS, (bps))
+
+/* Transmission time (nanoseconds) for a packet containing (syms) symbols */
+#define MCS_SYMBOL_TIME(sgi, syms) \
+ (sgi ? \
+ ((syms) * 18000 + 4000) / 5 : /* syms * 3.6 us */ \
+ ((syms) * 1000) << 2 /* syms * 4 us */ \
+ )
+
+/* Transmit duration for the raw data part of an average sized packet */
+#define MCS_DURATION(streams, sgi, bps) \
+ (MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps))) / AVG_AMPDU_SIZE)
+
+#define BW_20 0
+#define BW_40 1
+#define BW_80 2
+
+/*
+ * Define group sort order: HT40 -> SGI -> #streams
+ */
+#define GROUP_IDX(_streams, _sgi, _ht40) \
+ MINSTREL_HT_GROUP_0 + \
+ MINSTREL_MAX_STREAMS * 2 * _ht40 + \
+ MINSTREL_MAX_STREAMS * _sgi + \
+ _streams - 1
+
+/* MCS rate information for an MCS group */
+#define MCS_GROUP(_streams, _sgi, _ht40) \
+ [GROUP_IDX(_streams, _sgi, _ht40)] = { \
+ .streams = _streams, \
+ .flags = \
+ IEEE80211_TX_RC_MCS | \
+ (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
+ (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
+ .duration = { \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \
+ } \
+}
+
+#define VHT_GROUP_IDX(_streams, _sgi, _bw) \
+ (MINSTREL_VHT_GROUP_0 + \
+ MINSTREL_MAX_STREAMS * 2 * (_bw) + \
+ MINSTREL_MAX_STREAMS * (_sgi) + \
+ (_streams) - 1)
+
+#define BW2VBPS(_bw, r3, r2, r1) \
+ (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1)
+
+#define VHT_GROUP(_streams, _sgi, _bw) \
+ [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \
+ .streams = _streams, \
+ .flags = \
+ IEEE80211_TX_RC_VHT_MCS | \
+ (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \
+ (_bw == BW_80 ? IEEE80211_TX_RC_80_MHZ_WIDTH : \
+ _bw == BW_40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \
+ .duration = { \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 117, 54, 26)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 234, 108, 52)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 351, 162, 78)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 468, 216, 104)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 702, 324, 156)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 936, 432, 208)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1053, 486, 234)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1170, 540, 260)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1404, 648, 312)), \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1560, 720, 346)) \
+ } \
+}
+
+#define CCK_DURATION(_bitrate, _short, _len) \
+ (1000 * (10 /* SIFS */ + \
+ (_short ? 72 + 24 : 144 + 48) + \
+ (8 * (_len + 4) * 10) / (_bitrate)))
+
+#define CCK_ACK_DURATION(_bitrate, _short) \
+ (CCK_DURATION((_bitrate > 10 ? 20 : 10), false, 60) + \
+ CCK_DURATION(_bitrate, _short, AVG_PKT_SIZE))
+
+#define CCK_DURATION_LIST(_short) \
+ CCK_ACK_DURATION(10, _short), \
+ CCK_ACK_DURATION(20, _short), \
+ CCK_ACK_DURATION(55, _short), \
+ CCK_ACK_DURATION(110, _short)
+
+#define CCK_GROUP \
+ [MINSTREL_CCK_GROUP] = { \
+ .streams = 0, \
+ .flags = 0, \
+ .duration = { \
+ CCK_DURATION_LIST(false), \
+ CCK_DURATION_LIST(true) \
+ } \
+ }
+
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+static bool minstrel_vht_only = true;
+module_param(minstrel_vht_only, bool, 0644);
+MODULE_PARM_DESC(minstrel_vht_only,
+ "Use only VHT rates when VHT is supported by sta.");
+#endif
+
+/*
+ * To enable sufficiently targeted rate sampling, MCS rates are divided into
+ * groups, based on the number of streams and flags (HT40, SGI) that they
+ * use.
+ *
+ * Sortorder has to be fixed for GROUP_IDX macro to be applicable:
+ * BW -> SGI -> #streams
+ */
+const struct mcs_group minstrel_mcs_groups[] = {
+ MCS_GROUP(1, 0, BW_20),
+ MCS_GROUP(2, 0, BW_20),
+#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 0, BW_20),
+#endif
+
+ MCS_GROUP(1, 1, BW_20),
+ MCS_GROUP(2, 1, BW_20),
+#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 1, BW_20),
+#endif
+
+ MCS_GROUP(1, 0, BW_40),
+ MCS_GROUP(2, 0, BW_40),
+#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 0, BW_40),
+#endif
+
+ MCS_GROUP(1, 1, BW_40),
+ MCS_GROUP(2, 1, BW_40),
+#if MINSTREL_MAX_STREAMS >= 3
+ MCS_GROUP(3, 1, BW_40),
+#endif
+
+ CCK_GROUP,
+
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+ VHT_GROUP(1, 0, BW_20),
+ VHT_GROUP(2, 0, BW_20),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_20),
+#endif
+
+ VHT_GROUP(1, 1, BW_20),
+ VHT_GROUP(2, 1, BW_20),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_20),
+#endif
+
+ VHT_GROUP(1, 0, BW_40),
+ VHT_GROUP(2, 0, BW_40),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_40),
+#endif
+
+ VHT_GROUP(1, 1, BW_40),
+ VHT_GROUP(2, 1, BW_40),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_40),
+#endif
+
+ VHT_GROUP(1, 0, BW_80),
+ VHT_GROUP(2, 0, BW_80),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 0, BW_80),
+#endif
+
+ VHT_GROUP(1, 1, BW_80),
+ VHT_GROUP(2, 1, BW_80),
+#if MINSTREL_MAX_STREAMS >= 3
+ VHT_GROUP(3, 1, BW_80),
+#endif
+#endif
+};
+
+static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly;
+
+static void
+minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi);
+
+/*
+ * Some VHT MCSes are invalid (when Ndbps / Nes is not an integer)
+ * e.g for MCS9@20MHzx1Nss: Ndbps=8x52*(5/6) Nes=1
+ *
+ * Returns the valid mcs map for struct minstrel_mcs_group_data.supported
+ */
+static u16
+minstrel_get_valid_vht_rates(int bw, int nss, __le16 mcs_map)
+{
+ u16 mask = 0;
+
+ if (bw == BW_20) {
+ if (nss != 3 && nss != 6)
+ mask = BIT(9);
+ } else if (bw == BW_80) {
+ if (nss == 3 || nss == 7)
+ mask = BIT(6);
+ else if (nss == 6)
+ mask = BIT(9);
+ } else {
+ WARN_ON(bw != BW_40);
+ }
+
+ switch ((le16_to_cpu(mcs_map) >> (2 * (nss - 1))) & 3) {
+ case IEEE80211_VHT_MCS_SUPPORT_0_7:
+ mask |= 0x300;
+ break;
+ case IEEE80211_VHT_MCS_SUPPORT_0_8:
+ mask |= 0x200;
+ break;
+ case IEEE80211_VHT_MCS_SUPPORT_0_9:
+ break;
+ default:
+ mask = 0x3ff;
+ }
+
+ return 0x3ff & ~mask;
+}
+
+/*
+ * Look up an MCS group index based on mac80211 rate information
+ */
+static int
+minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate)
+{
+ return GROUP_IDX((rate->idx / 8) + 1,
+ !!(rate->flags & IEEE80211_TX_RC_SHORT_GI),
+ !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH));
+}
+
+static int
+minstrel_vht_get_group_idx(struct ieee80211_tx_rate *rate)
+{
+ return VHT_GROUP_IDX(ieee80211_rate_get_vht_nss(rate),
+ !!(rate->flags & IEEE80211_TX_RC_SHORT_GI),
+ !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) +
+ 2*!!(rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH));
+}
+
+static struct minstrel_rate_stats *
+minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
+ struct ieee80211_tx_rate *rate)
+{
+ int group, idx;
+
+ if (rate->flags & IEEE80211_TX_RC_MCS) {
+ group = minstrel_ht_get_group_idx(rate);
+ idx = rate->idx % 8;
+ } else if (rate->flags & IEEE80211_TX_RC_VHT_MCS) {
+ group = minstrel_vht_get_group_idx(rate);
+ idx = ieee80211_rate_get_vht_mcs(rate);
+ } else {
+ group = MINSTREL_CCK_GROUP;
+
+ for (idx = 0; idx < ARRAY_SIZE(mp->cck_rates); idx++)
+ if (rate->idx == mp->cck_rates[idx])
+ break;
+
+ /* short preamble */
+ if (!(mi->groups[group].supported & BIT(idx)))
+ idx += 4;
+ }
+ return &mi->groups[group].rates[idx];
+}
+
+static inline struct minstrel_rate_stats *
+minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index)
+{
+ return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES];
+}
+
+/*
+ * Return current throughput based on the average A-MPDU length, taking into
+ * account the expected number of retransmissions and their expected length
+ */
+int
+minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate,
+ int prob_ewma)
+{
+ unsigned int nsecs = 0;
+
+ /* do not account throughput if sucess prob is below 10% */
+ if (prob_ewma < MINSTREL_FRAC(10, 100))
+ return 0;
+
+ if (group != MINSTREL_CCK_GROUP)
+ nsecs = 1000 * mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len);
+
+ nsecs += minstrel_mcs_groups[group].duration[rate];
+
+ /*
+ * For the throughput calculation, limit the probability value to 90% to
+ * account for collision related packet error rate fluctuation
+ * (prob is scaled - see MINSTREL_FRAC above)
+ */
+ if (prob_ewma > MINSTREL_FRAC(90, 100))
+ return MINSTREL_TRUNC(100000 * ((MINSTREL_FRAC(90, 100) * 1000)
+ / nsecs));
+ else
+ return MINSTREL_TRUNC(100000 * ((prob_ewma * 1000) / nsecs));
+}
+
+/*
+ * Find & sort topmost throughput rates
+ *
+ * If multiple rates provide equal throughput the sorting is based on their
+ * current success probability. Higher success probability is preferred among
+ * MCS groups, CCK rates do not provide aggregation and are therefore at last.
+ */
+static void
+minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index,
+ u16 *tp_list)
+{
+ int cur_group, cur_idx, cur_tp_avg, cur_prob;
+ int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
+ int j = MAX_THR_RATES;
+
+ cur_group = index / MCS_GROUP_RATES;
+ cur_idx = index % MCS_GROUP_RATES;
+ cur_prob = mi->groups[cur_group].rates[cur_idx].prob_ewma;
+ cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, cur_prob);
+
+ do {
+ tmp_group = tp_list[j - 1] / MCS_GROUP_RATES;
+ tmp_idx = tp_list[j - 1] % MCS_GROUP_RATES;
+ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
+ tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx,
+ tmp_prob);
+ if (cur_tp_avg < tmp_tp_avg ||
+ (cur_tp_avg == tmp_tp_avg && cur_prob <= tmp_prob))
+ break;
+ j--;
+ } while (j > 0);
+
+ if (j < MAX_THR_RATES - 1) {
+ memmove(&tp_list[j + 1], &tp_list[j], (sizeof(*tp_list) *
+ (MAX_THR_RATES - (j + 1))));
+ }
+ if (j < MAX_THR_RATES)
+ tp_list[j] = index;
+}
+
+/*
+ * Find and set the topmost probability rate per sta and per group
+ */
+static void
+minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index)
+{
+ struct minstrel_mcs_group_data *mg;
+ struct minstrel_rate_stats *mrs;
+ int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob;
+ int max_tp_group, cur_tp_avg, cur_group, cur_idx;
+ int max_gpr_group, max_gpr_idx;
+ int max_gpr_tp_avg, max_gpr_prob;
+
+ cur_group = index / MCS_GROUP_RATES;
+ cur_idx = index % MCS_GROUP_RATES;
+ mg = &mi->groups[index / MCS_GROUP_RATES];
+ mrs = &mg->rates[index % MCS_GROUP_RATES];
+
+ tmp_group = mi->max_prob_rate / MCS_GROUP_RATES;
+ tmp_idx = mi->max_prob_rate % MCS_GROUP_RATES;
+ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
+ tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
+
+ /* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from
+ * MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */
+ max_tp_group = mi->max_tp_rate[0] / MCS_GROUP_RATES;
+ if((index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) &&
+ (max_tp_group != MINSTREL_CCK_GROUP))
+ return;
+
+ if (mrs->prob_ewma > MINSTREL_FRAC(75, 100)) {
+ cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx,
+ mrs->prob_ewma);
+ if (cur_tp_avg > tmp_tp_avg)
+ mi->max_prob_rate = index;
+
+ max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES;
+ max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
+ max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_ewma;
+ max_gpr_tp_avg = minstrel_ht_get_tp_avg(mi, max_gpr_group,
+ max_gpr_idx,
+ max_gpr_prob);
+ if (cur_tp_avg > max_gpr_tp_avg)
+ mg->max_group_prob_rate = index;
+ } else {
+ if (mrs->prob_ewma > tmp_prob)
+ mi->max_prob_rate = index;
+ if (mrs->prob_ewma > mg->rates[mg->max_group_prob_rate].prob_ewma)
+ mg->max_group_prob_rate = index;
+ }
+}
+
+
+/*
+ * Assign new rate set per sta and use CCK rates only if the fastest
+ * rate (max_tp_rate[0]) is from CCK group. This prohibits such sorted
+ * rate sets where MCS and CCK rates are mixed, because CCK rates can
+ * not use aggregation.
+ */
+static void
+minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi,
+ u16 tmp_mcs_tp_rate[MAX_THR_RATES],
+ u16 tmp_cck_tp_rate[MAX_THR_RATES])
+{
+ unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob;
+ int i;
+
+ tmp_group = tmp_cck_tp_rate[0] / MCS_GROUP_RATES;
+ tmp_idx = tmp_cck_tp_rate[0] % MCS_GROUP_RATES;
+ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
+ tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
+
+ tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES;
+ tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES;
+ tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma;
+ tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob);
+
+ if (tmp_cck_tp > tmp_mcs_tp) {
+ for(i = 0; i < MAX_THR_RATES; i++) {
+ minstrel_ht_sort_best_tp_rates(mi, tmp_cck_tp_rate[i],
+ tmp_mcs_tp_rate);
+ }
+ }
+
+}
+
+/*
+ * Try to increase robustness of max_prob rate by decrease number of
+ * streams if possible.
+ */
+static inline void
+minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi)
+{
+ struct minstrel_mcs_group_data *mg;
+ int tmp_max_streams, group, tmp_idx, tmp_prob;
+ int tmp_tp = 0;
+
+ tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] /
+ MCS_GROUP_RATES].streams;
+ for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
+ mg = &mi->groups[group];
+ if (!mg->supported || group == MINSTREL_CCK_GROUP)
+ continue;
+
+ tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES;
+ tmp_prob = mi->groups[group].rates[tmp_idx].prob_ewma;
+
+ if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) &&
+ (minstrel_mcs_groups[group].streams < tmp_max_streams)) {
+ mi->max_prob_rate = mg->max_group_prob_rate;
+ tmp_tp = minstrel_ht_get_tp_avg(mi, group,
+ tmp_idx,
+ tmp_prob);
+ }
+ }
+}
+
+/*
+ * Update rate statistics and select new primary rates
+ *
+ * Rules for rate selection:
+ * - max_prob_rate must use only one stream, as a tradeoff between delivery
+ * probability and throughput during strong fluctuations
+ * - as long as the max prob rate has a probability of more than 75%, pick
+ * higher throughput rates, even if the probablity is a bit lower
+ */
+static void
+minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
+{
+ struct minstrel_mcs_group_data *mg;
+ struct minstrel_rate_stats *mrs;
+ int group, i, j, cur_prob;
+ u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES];
+ u16 tmp_cck_tp_rate[MAX_THR_RATES], index;
+
+ if (mi->ampdu_packets > 0) {
+ mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len,
+ MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL);
+ mi->ampdu_len = 0;
+ mi->ampdu_packets = 0;
+ }
+
+ mi->sample_slow = 0;
+ mi->sample_count = 0;
+
+ /* Initialize global rate indexes */
+ for(j = 0; j < MAX_THR_RATES; j++){
+ tmp_mcs_tp_rate[j] = 0;
+ tmp_cck_tp_rate[j] = 0;
+ }
+
+ /* Find best rate sets within all MCS groups*/
+ for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) {
+
+ mg = &mi->groups[group];
+ if (!mg->supported)
+ continue;
+
+ mi->sample_count++;
+
+ /* (re)Initialize group rate indexes */
+ for(j = 0; j < MAX_THR_RATES; j++)
+ tmp_group_tp_rate[j] = group;
+
+ for (i = 0; i < MCS_GROUP_RATES; i++) {
+ if (!(mg->supported & BIT(i)))
+ continue;
+
+ index = MCS_GROUP_RATES * group + i;
+
+ mrs = &mg->rates[i];
+ mrs->retry_updated = false;
+ minstrel_calc_rate_stats(mrs);
+ cur_prob = mrs->prob_ewma;
+
+ if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0)
+ continue;
+
+ /* Find max throughput rate set */
+ if (group != MINSTREL_CCK_GROUP) {
+ minstrel_ht_sort_best_tp_rates(mi, index,
+ tmp_mcs_tp_rate);
+ } else if (group == MINSTREL_CCK_GROUP) {
+ minstrel_ht_sort_best_tp_rates(mi, index,
+ tmp_cck_tp_rate);
+ }
+
+ /* Find max throughput rate set within a group */
+ minstrel_ht_sort_best_tp_rates(mi, index,
+ tmp_group_tp_rate);
+
+ /* Find max probability rate per group and global */
+ minstrel_ht_set_best_prob_rate(mi, index);
+ }
+
+ memcpy(mg->max_group_tp_rate, tmp_group_tp_rate,
+ sizeof(mg->max_group_tp_rate));
+ }
+
+ /* Assign new rate set per sta */
+ minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, tmp_cck_tp_rate);
+ memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate));
+
+ /* Try to increase robustness of max_prob_rate*/
+ minstrel_ht_prob_rate_reduce_streams(mi);
+
+ /* try to sample all available rates during each interval */
+ mi->sample_count *= 8;
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+ /* use fixed index if set */
+ if (mp->fixed_rate_idx != -1) {
+ for (i = 0; i < 4; i++)
+ mi->max_tp_rate[i] = mp->fixed_rate_idx;
+ mi->max_prob_rate = mp->fixed_rate_idx;
+ }
+#endif
+
+ /* Reset update timer */
+ mi->last_stats_update = jiffies;
+}
+
+static bool
+minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct ieee80211_tx_rate *rate)
+{
+ if (rate->idx < 0)
+ return false;
+
+ if (!rate->count)
+ return false;
+
+ if (rate->flags & IEEE80211_TX_RC_MCS ||
+ rate->flags & IEEE80211_TX_RC_VHT_MCS)
+ return true;
+
+ return rate->idx == mp->cck_rates[0] ||
+ rate->idx == mp->cck_rates[1] ||
+ rate->idx == mp->cck_rates[2] ||
+ rate->idx == mp->cck_rates[3];
+}
+
+static void
+minstrel_set_next_sample_idx(struct minstrel_ht_sta *mi)
+{
+ struct minstrel_mcs_group_data *mg;
+
+ for (;;) {
+ mi->sample_group++;
+ mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups);
+ mg = &mi->groups[mi->sample_group];
+
+ if (!mg->supported)
+ continue;
+
+ if (++mg->index >= MCS_GROUP_RATES) {
+ mg->index = 0;
+ if (++mg->column >= ARRAY_SIZE(sample_table))
+ mg->column = 0;
+ }
+ break;
+ }
+}
+
+static void
+minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary)
+{
+ int group, orig_group;
+
+ orig_group = group = *idx / MCS_GROUP_RATES;
+ while (group > 0) {
+ group--;
+
+ if (!mi->groups[group].supported)
+ continue;
+
+ if (minstrel_mcs_groups[group].streams >
+ minstrel_mcs_groups[orig_group].streams)
+ continue;
+
+ if (primary)
+ *idx = mi->groups[group].max_group_tp_rate[0];
+ else
+ *idx = mi->groups[group].max_group_tp_rate[1];
+ break;
+ }
+}
+
+static void
+minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb)
+{
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+ struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
+ u16 tid;
+
+ if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO)
+ return;
+
+ if (unlikely(!ieee80211_is_data_qos(hdr->frame_control)))
+ return;
+
+ if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE)))
+ return;
+
+ tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
+ if (likely(sta->ampdu_mlme.tid_tx[tid]))
+ return;
+
+ ieee80211_start_tx_ba_session(pubsta, tid, 5000);
+}
+
+static void
+minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta, void *priv_sta,
+ struct ieee80211_tx_info *info)
+{
+ struct minstrel_ht_sta_priv *msp = priv_sta;
+ struct minstrel_ht_sta *mi = &msp->ht;
+ struct ieee80211_tx_rate *ar = info->status.rates;
+ struct minstrel_rate_stats *rate, *rate2;
+ struct minstrel_priv *mp = priv;
+ bool last, update = false;
+ int i;
+
+ if (!msp->is_ht)
+ return mac80211_minstrel.tx_status_noskb(priv, sband, sta,
+ &msp->legacy, info);
+
+ /* This packet was aggregated but doesn't carry status info */
+ if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
+ !(info->flags & IEEE80211_TX_STAT_AMPDU))
+ return;
+
+ if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) {
+ info->status.ampdu_ack_len =
+ (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0);
+ info->status.ampdu_len = 1;
+ }
+
+ mi->ampdu_packets++;
+ mi->ampdu_len += info->status.ampdu_len;
+
+ if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) {
+ mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len);
+ mi->sample_tries = 1;
+ mi->sample_count--;
+ }
+
+ if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
+ mi->sample_packets += info->status.ampdu_len;
+
+ last = !minstrel_ht_txstat_valid(mp, &ar[0]);
+ for (i = 0; !last; i++) {
+ last = (i == IEEE80211_TX_MAX_RATES - 1) ||
+ !minstrel_ht_txstat_valid(mp, &ar[i + 1]);
+
+ rate = minstrel_ht_get_stats(mp, mi, &ar[i]);
+
+ if (last)
+ rate->success += info->status.ampdu_ack_len;
+
+ rate->attempts += ar[i].count * info->status.ampdu_len;
+ }
+
+ /*
+ * check for sudden death of spatial multiplexing,
+ * downgrade to a lower number of streams if necessary.
+ */
+ rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]);
+ if (rate->attempts > 30 &&
+ MINSTREL_FRAC(rate->success, rate->attempts) <
+ MINSTREL_FRAC(20, 100)) {
+ minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true);
+ update = true;
+ }
+
+ rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]);
+ if (rate2->attempts > 30 &&
+ MINSTREL_FRAC(rate2->success, rate2->attempts) <
+ MINSTREL_FRAC(20, 100)) {
+ minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false);
+ update = true;
+ }
+
+ if (time_after(jiffies, mi->last_stats_update +
+ (mp->update_interval / 2 * HZ) / 1000)) {
+ update = true;
+ minstrel_ht_update_stats(mp, mi);
+ }
+
+ if (update)
+ minstrel_ht_update_rates(mp, mi);
+}
+
+static void
+minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
+ int index)
+{
+ struct minstrel_rate_stats *mrs;
+ const struct mcs_group *group;
+ unsigned int tx_time, tx_time_rtscts, tx_time_data;
+ unsigned int cw = mp->cw_min;
+ unsigned int ctime = 0;
+ unsigned int t_slot = 9; /* FIXME */
+ unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len);
+ unsigned int overhead = 0, overhead_rtscts = 0;
+
+ mrs = minstrel_get_ratestats(mi, index);
+ if (mrs->prob_ewma < MINSTREL_FRAC(1, 10)) {
+ mrs->retry_count = 1;
+ mrs->retry_count_rtscts = 1;
+ return;
+ }
+
+ mrs->retry_count = 2;
+ mrs->retry_count_rtscts = 2;
+ mrs->retry_updated = true;
+
+ group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
+ tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len / 1000;
+
+ /* Contention time for first 2 tries */
+ ctime = (t_slot * cw) >> 1;
+ cw = min((cw << 1) | 1, mp->cw_max);
+ ctime += (t_slot * cw) >> 1;
+ cw = min((cw << 1) | 1, mp->cw_max);
+
+ if (index / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) {
+ overhead = mi->overhead;
+ overhead_rtscts = mi->overhead_rtscts;
+ }
+
+ /* Total TX time for data and Contention after first 2 tries */
+ tx_time = ctime + 2 * (overhead + tx_time_data);
+ tx_time_rtscts = ctime + 2 * (overhead_rtscts + tx_time_data);
+
+ /* See how many more tries we can fit inside segment size */
+ do {
+ /* Contention time for this try */
+ ctime = (t_slot * cw) >> 1;
+ cw = min((cw << 1) | 1, mp->cw_max);
+
+ /* Total TX time after this try */
+ tx_time += ctime + overhead + tx_time_data;
+ tx_time_rtscts += ctime + overhead_rtscts + tx_time_data;
+
+ if (tx_time_rtscts < mp->segment_size)
+ mrs->retry_count_rtscts++;
+ } while ((tx_time < mp->segment_size) &&
+ (++mrs->retry_count < mp->max_retry));
+}
+
+
+static void
+minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
+ struct ieee80211_sta_rates *ratetbl, int offset, int index)
+{
+ const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
+ struct minstrel_rate_stats *mrs;
+ u8 idx;
+ u16 flags = group->flags;
+
+ mrs = minstrel_get_ratestats(mi, index);
+ if (!mrs->retry_updated)
+ minstrel_calc_retransmit(mp, mi, index);
+
+ if (mrs->prob_ewma < MINSTREL_FRAC(20, 100) || !mrs->retry_count) {
+ ratetbl->rate[offset].count = 2;
+ ratetbl->rate[offset].count_rts = 2;
+ ratetbl->rate[offset].count_cts = 2;
+ } else {
+ ratetbl->rate[offset].count = mrs->retry_count;
+ ratetbl->rate[offset].count_cts = mrs->retry_count;
+ ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts;
+ }
+
+ if (index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP)
+ idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)];
+ else if (flags & IEEE80211_TX_RC_VHT_MCS)
+ idx = ((group->streams - 1) << 4) |
+ ((index % MCS_GROUP_RATES) & 0xF);
+ else
+ idx = index % MCS_GROUP_RATES + (group->streams - 1) * 8;
+
+ if (offset > 0) {
+ ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts;
+ flags |= IEEE80211_TX_RC_USE_RTS_CTS;
+ }
+
+ ratetbl->rate[offset].idx = idx;
+ ratetbl->rate[offset].flags = flags;
+}
+
+static void
+minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
+{
+ struct ieee80211_sta_rates *rates;
+ int i = 0;
+
+ rates = kzalloc(sizeof(*rates), GFP_ATOMIC);
+ if (!rates)
+ return;
+
+ /* Start with max_tp_rate[0] */
+ minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]);
+
+ if (mp->hw->max_rates >= 3) {
+ /* At least 3 tx rates supported, use max_tp_rate[1] next */
+ minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]);
+ }
+
+ if (mp->hw->max_rates >= 2) {
+ /*
+ * At least 2 tx rates supported, use max_prob_rate next */
+ minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate);
+ }
+
+ rates->rate[i].idx = -1;
+ rate_control_set_rates(mp->hw, mi->sta, rates);
+}
+
+static inline int
+minstrel_get_duration(int index)
+{
+ const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES];
+ return group->duration[index % MCS_GROUP_RATES];
+}
+
+static int
+minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi)
+{
+ struct minstrel_rate_stats *mrs;
+ struct minstrel_mcs_group_data *mg;
+ unsigned int sample_dur, sample_group, cur_max_tp_streams;
+ int sample_idx = 0;
+
+ if (mi->sample_wait > 0) {
+ mi->sample_wait--;
+ return -1;
+ }
+
+ if (!mi->sample_tries)
+ return -1;
+
+ sample_group = mi->sample_group;
+ mg = &mi->groups[sample_group];
+ sample_idx = sample_table[mg->column][mg->index];
+ minstrel_set_next_sample_idx(mi);
+
+ if (!(mg->supported & BIT(sample_idx)))
+ return -1;
+
+ mrs = &mg->rates[sample_idx];
+ sample_idx += sample_group * MCS_GROUP_RATES;
+
+ /*
+ * Sampling might add some overhead (RTS, no aggregation)
+ * to the frame. Hence, don't use sampling for the currently
+ * used rates.
+ */
+ if (sample_idx == mi->max_tp_rate[0] ||
+ sample_idx == mi->max_tp_rate[1] ||
+ sample_idx == mi->max_prob_rate)
+ return -1;
+
+ /*
+ * Do not sample if the probability is already higher than 95%
+ * to avoid wasting airtime.
+ */
+ if (mrs->prob_ewma > MINSTREL_FRAC(95, 100))
+ return -1;
+
+ /*
+ * Make sure that lower rates get sampled only occasionally,
+ * if the link is working perfectly.
+ */
+
+ cur_max_tp_streams = minstrel_mcs_groups[mi->max_tp_rate[0] /
+ MCS_GROUP_RATES].streams;
+ sample_dur = minstrel_get_duration(sample_idx);
+ if (sample_dur >= minstrel_get_duration(mi->max_tp_rate[1]) &&
+ (cur_max_tp_streams - 1 <
+ minstrel_mcs_groups[sample_group].streams ||
+ sample_dur >= minstrel_get_duration(mi->max_prob_rate))) {
+ if (mrs->sample_skipped < 20)
+ return -1;
+
+ if (mi->sample_slow++ > 2)
+ return -1;
+ }
+ mi->sample_tries--;
+
+ return sample_idx;
+}
+
+static void
+minstrel_ht_check_cck_shortpreamble(struct minstrel_priv *mp,
+ struct minstrel_ht_sta *mi, bool val)
+{
+ u8 supported = mi->groups[MINSTREL_CCK_GROUP].supported;
+
+ if (!supported || !mi->cck_supported_short)
+ return;
+
+ if (supported & (mi->cck_supported_short << (val * 4)))
+ return;
+
+ supported ^= mi->cck_supported_short | (mi->cck_supported_short << 4);
+ mi->groups[MINSTREL_CCK_GROUP].supported = supported;
+}
+
+static void
+minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta,
+ struct ieee80211_tx_rate_control *txrc)
+{
+ const struct mcs_group *sample_group;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
+ struct ieee80211_tx_rate *rate = &info->status.rates[0];
+ struct minstrel_ht_sta_priv *msp = priv_sta;
+ struct minstrel_ht_sta *mi = &msp->ht;
+ struct minstrel_priv *mp = priv;
+ int sample_idx;
+
+ if (rate_control_send_low(sta, priv_sta, txrc))
+ return;
+
+ if (!msp->is_ht)
+ return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc);
+
+ if (!(info->flags & IEEE80211_TX_CTL_AMPDU) &&
+ mi->max_prob_rate / MCS_GROUP_RATES != MINSTREL_CCK_GROUP)
+ minstrel_aggr_check(sta, txrc->skb);
+
+ info->flags |= mi->tx_flags;
+ minstrel_ht_check_cck_shortpreamble(mp, mi, txrc->short_preamble);
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+ if (mp->fixed_rate_idx != -1)
+ return;
+#endif
+
+ /* Don't use EAPOL frames for sampling on non-mrr hw */
+ if (mp->hw->max_rates == 1 &&
+ (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO))
+ sample_idx = -1;
+ else
+ sample_idx = minstrel_get_sample_rate(mp, mi);
+
+ mi->total_packets++;
+
+ /* wraparound */
+ if (mi->total_packets == ~0) {
+ mi->total_packets = 0;
+ mi->sample_packets = 0;
+ }
+
+ if (sample_idx < 0)
+ return;
+
+ sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES];
+ info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
+ rate->count = 1;
+
+ if (sample_idx / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) {
+ int idx = sample_idx % ARRAY_SIZE(mp->cck_rates);
+ rate->idx = mp->cck_rates[idx];
+ } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) {
+ ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES,
+ sample_group->streams);
+ } else {
+ rate->idx = sample_idx % MCS_GROUP_RATES +
+ (sample_group->streams - 1) * 8;
+ }
+
+ rate->flags = sample_group->flags;
+}
+
+static void
+minstrel_ht_update_cck(struct minstrel_priv *mp, struct minstrel_ht_sta *mi,
+ struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta)
+{
+ int i;
+
+ if (sband->band != IEEE80211_BAND_2GHZ)
+ return;
+
+ if (!(mp->hw->flags & IEEE80211_HW_SUPPORTS_HT_CCK_RATES))
+ return;
+
+ mi->cck_supported = 0;
+ mi->cck_supported_short = 0;
+ for (i = 0; i < 4; i++) {
+ if (!rate_supported(sta, sband->band, mp->cck_rates[i]))
+ continue;
+
+ mi->cck_supported |= BIT(i);
+ if (sband->bitrates[i].flags & IEEE80211_RATE_SHORT_PREAMBLE)
+ mi->cck_supported_short |= BIT(i);
+ }
+
+ mi->groups[MINSTREL_CCK_GROUP].supported = mi->cck_supported;
+}
+
+static void
+minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband,
+ struct cfg80211_chan_def *chandef,
+ struct ieee80211_sta *sta, void *priv_sta)
+{
+ struct minstrel_priv *mp = priv;
+ struct minstrel_ht_sta_priv *msp = priv_sta;
+ struct minstrel_ht_sta *mi = &msp->ht;
+ struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
+ u16 sta_cap = sta->ht_cap.cap;
+ struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
+ int use_vht;
+ int n_supported = 0;
+ int ack_dur;
+ int stbc;
+ int i;
+
+ /* fall back to the old minstrel for legacy stations */
+ if (!sta->ht_cap.ht_supported)
+ goto use_legacy;
+
+ BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB);
+
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+ if (vht_cap->vht_supported)
+ use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0);
+ else
+#endif
+ use_vht = 0;
+
+ msp->is_ht = true;
+ memset(mi, 0, sizeof(*mi));
+
+ mi->sta = sta;
+ mi->last_stats_update = jiffies;
+
+ ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1, 0);
+ mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1, 0);
+ mi->overhead += ack_dur;
+ mi->overhead_rtscts = mi->overhead + 2 * ack_dur;
+
+ mi->avg_ampdu_len = MINSTREL_FRAC(1, 1);
+
+ /* When using MRR, sample more on the first attempt, without delay */
+ if (mp->has_mrr) {
+ mi->sample_count = 16;
+ mi->sample_wait = 0;
+ } else {
+ mi->sample_count = 8;
+ mi->sample_wait = 8;
+ }
+ mi->sample_tries = 4;
+
+ /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */
+ if (!use_vht) {
+ stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
+ IEEE80211_HT_CAP_RX_STBC_SHIFT;
+ mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
+
+ if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
+ mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(mi->groups); i++) {
+ u32 gflags = minstrel_mcs_groups[i].flags;
+ int bw, nss;
+
+ mi->groups[i].supported = 0;
+ if (i == MINSTREL_CCK_GROUP) {
+ minstrel_ht_update_cck(mp, mi, sband, sta);
+ continue;
+ }
+
+ if (gflags & IEEE80211_TX_RC_SHORT_GI) {
+ if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
+ if (!(sta_cap & IEEE80211_HT_CAP_SGI_40))
+ continue;
+ } else {
+ if (!(sta_cap & IEEE80211_HT_CAP_SGI_20))
+ continue;
+ }
+ }
+
+ if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH &&
+ sta->bandwidth < IEEE80211_STA_RX_BW_40)
+ continue;
+
+ nss = minstrel_mcs_groups[i].streams;
+
+ /* Mark MCS > 7 as unsupported if STA is in static SMPS mode */
+ if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1)
+ continue;
+
+ /* HT rate */
+ if (gflags & IEEE80211_TX_RC_MCS) {
+#ifdef CONFIG_MAC80211_RC_MINSTREL_VHT
+ if (use_vht && minstrel_vht_only)
+ continue;
+#endif
+ mi->groups[i].supported = mcs->rx_mask[nss - 1];
+ if (mi->groups[i].supported)
+ n_supported++;
+ continue;
+ }
+
+ /* VHT rate */
+ if (!vht_cap->vht_supported ||
+ WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) ||
+ WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH))
+ continue;
+
+ if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) {
+ if (sta->bandwidth < IEEE80211_STA_RX_BW_80 ||
+ ((gflags & IEEE80211_TX_RC_SHORT_GI) &&
+ !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) {
+ continue;
+ }
+ }
+
+ if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH)
+ bw = BW_40;
+ else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH)
+ bw = BW_80;
+ else
+ bw = BW_20;
+
+ mi->groups[i].supported = minstrel_get_valid_vht_rates(bw, nss,
+ vht_cap->vht_mcs.tx_mcs_map);
+
+ if (mi->groups[i].supported)
+ n_supported++;
+ }
+
+ if (!n_supported)
+ goto use_legacy;
+
+ /* create an initial rate table with the lowest supported rates */
+ minstrel_ht_update_stats(mp, mi);
+ minstrel_ht_update_rates(mp, mi);
+
+ return;
+
+use_legacy:
+ msp->is_ht = false;
+ memset(&msp->legacy, 0, sizeof(msp->legacy));
+ msp->legacy.r = msp->ratelist;
+ msp->legacy.sample_table = msp->sample_table;
+ return mac80211_minstrel.rate_init(priv, sband, chandef, sta,
+ &msp->legacy);
+}
+
+static void
+minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband,
+ struct cfg80211_chan_def *chandef,
+ struct ieee80211_sta *sta, void *priv_sta)
+{
+ minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta);
+}
+
+static void
+minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband,
+ struct cfg80211_chan_def *chandef,
+ struct ieee80211_sta *sta, void *priv_sta,
+ u32 changed)
+{
+ minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta);
+}
+
+static void *
+minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp)
+{
+ struct ieee80211_supported_band *sband;
+ struct minstrel_ht_sta_priv *msp;
+ struct minstrel_priv *mp = priv;
+ struct ieee80211_hw *hw = mp->hw;
+ int max_rates = 0;
+ int i;
+
+ for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
+ sband = hw->wiphy->bands[i];
+ if (sband && sband->n_bitrates > max_rates)
+ max_rates = sband->n_bitrates;
+ }
+
+ msp = kzalloc(sizeof(*msp), gfp);
+ if (!msp)
+ return NULL;
+
+ msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp);
+ if (!msp->ratelist)
+ goto error;
+
+ msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp);
+ if (!msp->sample_table)
+ goto error1;
+
+ return msp;
+
+error1:
+ kfree(msp->ratelist);
+error:
+ kfree(msp);
+ return NULL;
+}
+
+static void
+minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta)
+{
+ struct minstrel_ht_sta_priv *msp = priv_sta;
+
+ kfree(msp->sample_table);
+ kfree(msp->ratelist);
+ kfree(msp);
+}
+
+static void *
+minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
+{
+ return mac80211_minstrel.alloc(hw, debugfsdir);
+}
+
+static void
+minstrel_ht_free(void *priv)
+{
+ mac80211_minstrel.free(priv);
+}
+
+static u32 minstrel_ht_get_expected_throughput(void *priv_sta)
+{
+ struct minstrel_ht_sta_priv *msp = priv_sta;
+ struct minstrel_ht_sta *mi = &msp->ht;
+ int i, j, prob, tp_avg;
+
+ if (!msp->is_ht)
+ return mac80211_minstrel.get_expected_throughput(priv_sta);
+
+ i = mi->max_tp_rate[0] / MCS_GROUP_RATES;
+ j = mi->max_tp_rate[0] % MCS_GROUP_RATES;
+ prob = mi->groups[i].rates[j].prob_ewma;
+
+ /* convert tp_avg from pkt per second in kbps */
+ tp_avg = minstrel_ht_get_tp_avg(mi, i, j, prob) * AVG_PKT_SIZE * 8 / 1024;
+
+ return tp_avg;
+}
+
+static const struct rate_control_ops mac80211_minstrel_ht = {
+ .name = "minstrel_ht",
+ .tx_status_noskb = minstrel_ht_tx_status,
+ .get_rate = minstrel_ht_get_rate,
+ .rate_init = minstrel_ht_rate_init,
+ .rate_update = minstrel_ht_rate_update,
+ .alloc_sta = minstrel_ht_alloc_sta,
+ .free_sta = minstrel_ht_free_sta,
+ .alloc = minstrel_ht_alloc,
+ .free = minstrel_ht_free,
+#ifdef CONFIG_MAC80211_DEBUGFS
+ .add_sta_debugfs = minstrel_ht_add_sta_debugfs,
+ .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs,
+#endif
+ .get_expected_throughput = minstrel_ht_get_expected_throughput,
+};
+
+
+static void __init init_sample_table(void)
+{
+ int col, i, new_idx;
+ u8 rnd[MCS_GROUP_RATES];
+
+ memset(sample_table, 0xff, sizeof(sample_table));
+ for (col = 0; col < SAMPLE_COLUMNS; col++) {
+ prandom_bytes(rnd, sizeof(rnd));
+ for (i = 0; i < MCS_GROUP_RATES; i++) {
+ new_idx = (i + rnd[i]) % MCS_GROUP_RATES;
+ while (sample_table[col][new_idx] != 0xff)
+ new_idx = (new_idx + 1) % MCS_GROUP_RATES;
+
+ sample_table[col][new_idx] = i;
+ }
+ }
+}
+
+int __init
+rc80211_minstrel_ht_init(void)
+{
+ init_sample_table();
+ return ieee80211_rate_control_register(&mac80211_minstrel_ht);
+}
+
+void
+rc80211_minstrel_ht_exit(void)
+{
+ ieee80211_rate_control_unregister(&mac80211_minstrel_ht);
+}
Code Review / kvmfornfv.git / blobdiff