diff options
Diffstat (limited to 'drivers/net/wireless/mediatek/mt76/airtime.c')
| -rw-r--r-- | drivers/net/wireless/mediatek/mt76/airtime.c | 326 |
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); |