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Diffstat (limited to 'drivers/net/wireless/mediatek/mt76/airtime.c')
-rw-r--r--drivers/net/wireless/mediatek/mt76/airtime.c326
1 files changed, 326 insertions, 0 deletions
diff --git a/drivers/net/wireless/mediatek/mt76/airtime.c b/drivers/net/wireless/mediatek/mt76/airtime.c
new file mode 100644
index 000000000000..55116f395f9a
--- /dev/null
+++ b/drivers/net/wireless/mediatek/mt76/airtime.c
@@ -0,0 +1,326 @@
+// SPDX-License-Identifier: ISC
+/*
+ * Copyright (C) 2019 Felix Fietkau <nbd@nbd.name>
+ */
+
+#include "mt76.h"
+
+#define AVG_PKT_SIZE 1024
+
+/* Number of bits for an average sized packet */
+#define MCS_NBITS (AVG_PKT_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 (1024 usec) for a packet containing (syms) * symbols */
+#define MCS_SYMBOL_TIME(sgi, syms) \
+ (sgi ? \
+ ((syms) * 18 * 1024 + 4 * 1024) / 5 : /* syms * 3.6 us */ \
+ ((syms) * 1024) << 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)))
+
+#define BW_20 0
+#define BW_40 1
+#define BW_80 2
+
+/*
+ * Define group sort order: HT40 -> SGI -> #streams
+ */
+#define MT_MAX_STREAMS 4
+#define MT_HT_STREAM_GROUPS 4 /* BW(=2) * SGI(=2) */
+#define MT_VHT_STREAM_GROUPS 6 /* BW(=3) * SGI(=2) */
+
+#define MT_HT_GROUPS_NB (MT_MAX_STREAMS * \
+ MT_HT_STREAM_GROUPS)
+#define MT_VHT_GROUPS_NB (MT_MAX_STREAMS * \
+ MT_VHT_STREAM_GROUPS)
+#define MT_GROUPS_NB (MT_HT_GROUPS_NB + \
+ MT_VHT_GROUPS_NB)
+
+#define MT_HT_GROUP_0 0
+#define MT_VHT_GROUP_0 (MT_HT_GROUP_0 + MT_HT_GROUPS_NB)
+
+#define MCS_GROUP_RATES 10
+
+#define HT_GROUP_IDX(_streams, _sgi, _ht40) \
+ MT_HT_GROUP_0 + \
+ MT_MAX_STREAMS * 2 * _ht40 + \
+ MT_MAX_STREAMS * _sgi + \
+ _streams - 1
+
+#define _MAX(a, b) (((a)>(b))?(a):(b))
+
+#define GROUP_SHIFT(duration) \
+ _MAX(0, 16 - __builtin_clz(duration))
+
+/* MCS rate information for an MCS group */
+#define __MCS_GROUP(_streams, _sgi, _ht40, _s) \
+ [HT_GROUP_IDX(_streams, _sgi, _ht40)] = { \
+ .shift = _s, \
+ .duration = { \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26) >> _s, \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52) >> _s, \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78) >> _s, \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104) >> _s, \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156) >> _s, \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208) >> _s, \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234) >> _s, \
+ MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) >> _s \
+ } \
+}
+
+#define MCS_GROUP_SHIFT(_streams, _sgi, _ht40) \
+ GROUP_SHIFT(MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26))
+
+#define MCS_GROUP(_streams, _sgi, _ht40) \
+ __MCS_GROUP(_streams, _sgi, _ht40, \
+ MCS_GROUP_SHIFT(_streams, _sgi, _ht40))
+
+#define VHT_GROUP_IDX(_streams, _sgi, _bw) \
+ (MT_VHT_GROUP_0 + \
+ MT_MAX_STREAMS * 2 * (_bw) + \
+ MT_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, _s) \
+ [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \
+ .shift = _s, \
+ .duration = { \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 117, 54, 26)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 234, 108, 52)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 351, 162, 78)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 468, 216, 104)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 702, 324, 156)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 936, 432, 208)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1053, 486, 234)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1170, 540, 260)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1404, 648, 312)) >> _s, \
+ MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 1560, 720, 346)) >> _s \
+ } \
+}
+
+#define VHT_GROUP_SHIFT(_streams, _sgi, _bw) \
+ GROUP_SHIFT(MCS_DURATION(_streams, _sgi, \
+ BW2VBPS(_bw, 117, 54, 26)))
+
+#define VHT_GROUP(_streams, _sgi, _bw) \
+ __VHT_GROUP(_streams, _sgi, _bw, \
+ VHT_GROUP_SHIFT(_streams, _sgi, _bw))
+
+struct mcs_group {
+ u8 shift;
+ u16 duration[MCS_GROUP_RATES];
+};
+
+static const struct mcs_group airtime_mcs_groups[] = {
+ MCS_GROUP(1, 0, BW_20),
+ MCS_GROUP(2, 0, BW_20),
+ MCS_GROUP(3, 0, BW_20),
+ MCS_GROUP(4, 0, BW_20),
+
+ MCS_GROUP(1, 1, BW_20),
+ MCS_GROUP(2, 1, BW_20),
+ MCS_GROUP(3, 1, BW_20),
+ MCS_GROUP(4, 1, BW_20),
+
+ MCS_GROUP(1, 0, BW_40),
+ MCS_GROUP(2, 0, BW_40),
+ MCS_GROUP(3, 0, BW_40),
+ MCS_GROUP(4, 0, BW_40),
+
+ MCS_GROUP(1, 1, BW_40),
+ MCS_GROUP(2, 1, BW_40),
+ MCS_GROUP(3, 1, BW_40),
+ MCS_GROUP(4, 1, BW_40),
+
+ VHT_GROUP(1, 0, BW_20),
+ VHT_GROUP(2, 0, BW_20),
+ VHT_GROUP(3, 0, BW_20),
+ VHT_GROUP(4, 0, BW_20),
+
+ VHT_GROUP(1, 1, BW_20),
+ VHT_GROUP(2, 1, BW_20),
+ VHT_GROUP(3, 1, BW_20),
+ VHT_GROUP(4, 1, BW_20),
+
+ VHT_GROUP(1, 0, BW_40),
+ VHT_GROUP(2, 0, BW_40),
+ VHT_GROUP(3, 0, BW_40),
+ VHT_GROUP(4, 0, BW_40),
+
+ VHT_GROUP(1, 1, BW_40),
+ VHT_GROUP(2, 1, BW_40),
+ VHT_GROUP(3, 1, BW_40),
+ VHT_GROUP(4, 1, BW_40),
+
+ VHT_GROUP(1, 0, BW_80),
+ VHT_GROUP(2, 0, BW_80),
+ VHT_GROUP(3, 0, BW_80),
+ VHT_GROUP(4, 0, BW_80),
+
+ VHT_GROUP(1, 1, BW_80),
+ VHT_GROUP(2, 1, BW_80),
+ VHT_GROUP(3, 1, BW_80),
+ VHT_GROUP(4, 1, BW_80),
+};
+
+static u32
+mt76_calc_legacy_rate_duration(const struct ieee80211_rate *rate, bool short_pre,
+ int len)
+{
+ u32 duration;
+
+ switch (rate->hw_value >> 8) {
+ case MT_PHY_TYPE_CCK:
+ duration = 144 + 48; /* preamble + PLCP */
+ if (short_pre)
+ duration >>= 1;
+
+ duration += 10; /* SIFS */
+ break;
+ case MT_PHY_TYPE_OFDM:
+ duration = 20 + 16; /* premable + SIFS */
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+
+ len <<= 3;
+ duration += (len * 10) / rate->bitrate;
+
+ return duration;
+}
+
+u32 mt76_calc_rx_airtime(struct mt76_dev *dev, struct mt76_rx_status *status,
+ int len)
+{
+ struct ieee80211_supported_band *sband;
+ const struct ieee80211_rate *rate;
+ bool sgi = status->enc_flags & RX_ENC_FLAG_SHORT_GI;
+ bool sp = status->enc_flags & RX_ENC_FLAG_SHORTPRE;
+ int bw, streams;
+ u32 duration;
+ int group, idx;
+
+ switch (status->bw) {
+ case RATE_INFO_BW_20:
+ bw = BW_20;
+ break;
+ case RATE_INFO_BW_40:
+ bw = BW_40;
+ break;
+ case RATE_INFO_BW_80:
+ bw = BW_80;
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+
+ switch (status->encoding) {
+ case RX_ENC_LEGACY:
+ if (WARN_ON_ONCE(status->band > NL80211_BAND_5GHZ))
+ return 0;
+
+ sband = dev->hw->wiphy->bands[status->band];
+ if (!sband || status->rate_idx > sband->n_bitrates)
+ return 0;
+
+ rate = &sband->bitrates[status->rate_idx];
+
+ return mt76_calc_legacy_rate_duration(rate, sp, len);
+ case RX_ENC_VHT:
+ streams = status->nss;
+ idx = status->rate_idx;
+ group = VHT_GROUP_IDX(streams, sgi, bw);
+ break;
+ case RX_ENC_HT:
+ streams = ((status->rate_idx >> 3) & 3) + 1;
+ idx = status->rate_idx & 7;
+ group = HT_GROUP_IDX(streams, sgi, bw);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+
+ if (WARN_ON_ONCE(streams > 4))
+ return 0;
+
+ duration = airtime_mcs_groups[group].duration[idx];
+ duration <<= airtime_mcs_groups[group].shift;
+ duration *= len;
+ duration /= AVG_PKT_SIZE;
+ duration /= 1024;
+
+ duration += 36 + (streams << 2);
+
+ return duration;
+}
+
+u32 mt76_calc_tx_airtime(struct mt76_dev *dev, struct ieee80211_tx_info *info,
+ int len)
+{
+ struct mt76_rx_status stat = {
+ .band = info->band,
+ };
+ u32 duration = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(info->status.rates); i++) {
+ struct ieee80211_tx_rate *rate = &info->status.rates[i];
+ u32 cur_duration;
+
+ if (rate->idx < 0 || !rate->count)
+ break;
+
+ if (rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
+ stat.bw = RATE_INFO_BW_80;
+ else if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
+ stat.bw = RATE_INFO_BW_40;
+ else
+ stat.bw = RATE_INFO_BW_20;
+
+ stat.enc_flags = 0;
+ if (rate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
+ stat.enc_flags |= RX_ENC_FLAG_SHORTPRE;
+ if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
+ stat.enc_flags |= RX_ENC_FLAG_SHORT_GI;
+
+ stat.rate_idx = rate->idx;
+ if (rate->flags & IEEE80211_TX_RC_VHT_MCS) {
+ stat.encoding = RX_ENC_VHT;
+ stat.rate_idx = ieee80211_rate_get_vht_mcs(rate);
+ stat.nss = ieee80211_rate_get_vht_nss(rate);
+ } else if (rate->flags & IEEE80211_TX_RC_MCS) {
+ stat.encoding = RX_ENC_HT;
+ } else {
+ stat.encoding = RX_ENC_LEGACY;
+ }
+
+ cur_duration = mt76_calc_rx_airtime(dev, &stat, len);
+ duration += cur_duration * rate->count;
+ }
+
+ return duration;
+}
+EXPORT_SYMBOL_GPL(mt76_calc_tx_airtime);