1 // SPDX-License-Identifier: ISC
3 * Copyright (C) 2019 Felix Fietkau <nbd@nbd.name>
8 #define AVG_PKT_SIZE 1024
10 /* Number of bits for an average sized packet */
11 #define MCS_NBITS (AVG_PKT_SIZE << 3)
13 /* Number of symbols for a packet with (bps) bits per symbol */
14 #define MCS_NSYMS(bps) DIV_ROUND_UP(MCS_NBITS, (bps))
16 /* Transmission time (1024 usec) for a packet containing (syms) * symbols */
17 #define MCS_SYMBOL_TIME(sgi, syms) \
19 ((syms) * 18 * 1024 + 4 * 1024) / 5 : /* syms * 3.6 us */ \
20 ((syms) * 1024) << 2 /* syms * 4 us */ \
23 /* Transmit duration for the raw data part of an average sized packet */
24 #define MCS_DURATION(streams, sgi, bps) \
25 MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps)))
32 * Define group sort order: HT40 -> SGI -> #streams
34 #define MT_MAX_STREAMS 4
35 #define MT_HT_STREAM_GROUPS 4 /* BW(=2) * SGI(=2) */
36 #define MT_VHT_STREAM_GROUPS 6 /* BW(=3) * SGI(=2) */
38 #define MT_HT_GROUPS_NB (MT_MAX_STREAMS * \
40 #define MT_VHT_GROUPS_NB (MT_MAX_STREAMS * \
42 #define MT_GROUPS_NB (MT_HT_GROUPS_NB + \
45 #define MT_HT_GROUP_0 0
46 #define MT_VHT_GROUP_0 (MT_HT_GROUP_0 + MT_HT_GROUPS_NB)
48 #define MCS_GROUP_RATES 10
50 #define HT_GROUP_IDX(_streams, _sgi, _ht40) \
52 MT_MAX_STREAMS * 2 * _ht40 + \
53 MT_MAX_STREAMS * _sgi + \
56 #define _MAX(a, b) (((a)>(b))?(a):(b))
58 #define GROUP_SHIFT(duration) \
59 _MAX(0, 16 - __builtin_clz(duration))
61 /* MCS rate information for an MCS group */
62 #define __MCS_GROUP(_streams, _sgi, _ht40, _s) \
63 [HT_GROUP_IDX(_streams, _sgi, _ht40)] = { \
66 MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26) >> _s, \
67 MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52) >> _s, \
68 MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78) >> _s, \
69 MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104) >> _s, \
70 MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156) >> _s, \
71 MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208) >> _s, \
72 MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234) >> _s, \
73 MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) >> _s \
77 #define MCS_GROUP_SHIFT(_streams, _sgi, _ht40) \
78 GROUP_SHIFT(MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26))
80 #define MCS_GROUP(_streams, _sgi, _ht40) \
81 __MCS_GROUP(_streams, _sgi, _ht40, \
82 MCS_GROUP_SHIFT(_streams, _sgi, _ht40))
84 #define VHT_GROUP_IDX(_streams, _sgi, _bw) \
86 MT_MAX_STREAMS * 2 * (_bw) + \
87 MT_MAX_STREAMS * (_sgi) + \
90 #define BW2VBPS(_bw, r3, r2, r1) \
91 (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1)
93 #define __VHT_GROUP(_streams, _sgi, _bw, _s) \
94 [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \
97 MCS_DURATION(_streams, _sgi, \
98 BW2VBPS(_bw, 117, 54, 26)) >> _s, \
99 MCS_DURATION(_streams, _sgi, \
100 BW2VBPS(_bw, 234, 108, 52)) >> _s, \
101 MCS_DURATION(_streams, _sgi, \
102 BW2VBPS(_bw, 351, 162, 78)) >> _s, \
103 MCS_DURATION(_streams, _sgi, \
104 BW2VBPS(_bw, 468, 216, 104)) >> _s, \
105 MCS_DURATION(_streams, _sgi, \
106 BW2VBPS(_bw, 702, 324, 156)) >> _s, \
107 MCS_DURATION(_streams, _sgi, \
108 BW2VBPS(_bw, 936, 432, 208)) >> _s, \
109 MCS_DURATION(_streams, _sgi, \
110 BW2VBPS(_bw, 1053, 486, 234)) >> _s, \
111 MCS_DURATION(_streams, _sgi, \
112 BW2VBPS(_bw, 1170, 540, 260)) >> _s, \
113 MCS_DURATION(_streams, _sgi, \
114 BW2VBPS(_bw, 1404, 648, 312)) >> _s, \
115 MCS_DURATION(_streams, _sgi, \
116 BW2VBPS(_bw, 1560, 720, 346)) >> _s \
120 #define VHT_GROUP_SHIFT(_streams, _sgi, _bw) \
121 GROUP_SHIFT(MCS_DURATION(_streams, _sgi, \
122 BW2VBPS(_bw, 117, 54, 26)))
124 #define VHT_GROUP(_streams, _sgi, _bw) \
125 __VHT_GROUP(_streams, _sgi, _bw, \
126 VHT_GROUP_SHIFT(_streams, _sgi, _bw))
130 u16 duration
[MCS_GROUP_RATES
];
133 static const struct mcs_group airtime_mcs_groups
[] = {
134 MCS_GROUP(1, 0, BW_20
),
135 MCS_GROUP(2, 0, BW_20
),
136 MCS_GROUP(3, 0, BW_20
),
137 MCS_GROUP(4, 0, BW_20
),
139 MCS_GROUP(1, 1, BW_20
),
140 MCS_GROUP(2, 1, BW_20
),
141 MCS_GROUP(3, 1, BW_20
),
142 MCS_GROUP(4, 1, BW_20
),
144 MCS_GROUP(1, 0, BW_40
),
145 MCS_GROUP(2, 0, BW_40
),
146 MCS_GROUP(3, 0, BW_40
),
147 MCS_GROUP(4, 0, BW_40
),
149 MCS_GROUP(1, 1, BW_40
),
150 MCS_GROUP(2, 1, BW_40
),
151 MCS_GROUP(3, 1, BW_40
),
152 MCS_GROUP(4, 1, BW_40
),
154 VHT_GROUP(1, 0, BW_20
),
155 VHT_GROUP(2, 0, BW_20
),
156 VHT_GROUP(3, 0, BW_20
),
157 VHT_GROUP(4, 0, BW_20
),
159 VHT_GROUP(1, 1, BW_20
),
160 VHT_GROUP(2, 1, BW_20
),
161 VHT_GROUP(3, 1, BW_20
),
162 VHT_GROUP(4, 1, BW_20
),
164 VHT_GROUP(1, 0, BW_40
),
165 VHT_GROUP(2, 0, BW_40
),
166 VHT_GROUP(3, 0, BW_40
),
167 VHT_GROUP(4, 0, BW_40
),
169 VHT_GROUP(1, 1, BW_40
),
170 VHT_GROUP(2, 1, BW_40
),
171 VHT_GROUP(3, 1, BW_40
),
172 VHT_GROUP(4, 1, BW_40
),
174 VHT_GROUP(1, 0, BW_80
),
175 VHT_GROUP(2, 0, BW_80
),
176 VHT_GROUP(3, 0, BW_80
),
177 VHT_GROUP(4, 0, BW_80
),
179 VHT_GROUP(1, 1, BW_80
),
180 VHT_GROUP(2, 1, BW_80
),
181 VHT_GROUP(3, 1, BW_80
),
182 VHT_GROUP(4, 1, BW_80
),
186 mt76_calc_legacy_rate_duration(const struct ieee80211_rate
*rate
, bool short_pre
,
191 switch (rate
->hw_value
>> 8) {
192 case MT_PHY_TYPE_CCK
:
193 duration
= 144 + 48; /* preamble + PLCP */
197 duration
+= 10; /* SIFS */
199 case MT_PHY_TYPE_OFDM
:
200 duration
= 20 + 16; /* premable + SIFS */
208 duration
+= (len
* 10) / rate
->bitrate
;
213 u32
mt76_calc_rx_airtime(struct mt76_dev
*dev
, struct mt76_rx_status
*status
,
216 struct ieee80211_supported_band
*sband
;
217 const struct ieee80211_rate
*rate
;
218 bool sgi
= status
->enc_flags
& RX_ENC_FLAG_SHORT_GI
;
219 bool sp
= status
->enc_flags
& RX_ENC_FLAG_SHORTPRE
;
224 switch (status
->bw
) {
225 case RATE_INFO_BW_20
:
228 case RATE_INFO_BW_40
:
231 case RATE_INFO_BW_80
:
239 switch (status
->encoding
) {
241 if (WARN_ON_ONCE(status
->band
> NL80211_BAND_5GHZ
))
244 sband
= dev
->hw
->wiphy
->bands
[status
->band
];
245 if (!sband
|| status
->rate_idx
> sband
->n_bitrates
)
248 rate
= &sband
->bitrates
[status
->rate_idx
];
250 return mt76_calc_legacy_rate_duration(rate
, sp
, len
);
252 streams
= status
->nss
;
253 idx
= status
->rate_idx
;
254 group
= VHT_GROUP_IDX(streams
, sgi
, bw
);
257 streams
= ((status
->rate_idx
>> 3) & 3) + 1;
258 idx
= status
->rate_idx
& 7;
259 group
= HT_GROUP_IDX(streams
, sgi
, bw
);
266 if (WARN_ON_ONCE(streams
> 4))
269 duration
= airtime_mcs_groups
[group
].duration
[idx
];
270 duration
<<= airtime_mcs_groups
[group
].shift
;
272 duration
/= AVG_PKT_SIZE
;
275 duration
+= 36 + (streams
<< 2);
280 u32
mt76_calc_tx_airtime(struct mt76_dev
*dev
, struct ieee80211_tx_info
*info
,
283 struct mt76_rx_status stat
= {
289 for (i
= 0; i
< ARRAY_SIZE(info
->status
.rates
); i
++) {
290 struct ieee80211_tx_rate
*rate
= &info
->status
.rates
[i
];
293 if (rate
->idx
< 0 || !rate
->count
)
296 if (rate
->flags
& IEEE80211_TX_RC_80_MHZ_WIDTH
)
297 stat
.bw
= RATE_INFO_BW_80
;
298 else if (rate
->flags
& IEEE80211_TX_RC_40_MHZ_WIDTH
)
299 stat
.bw
= RATE_INFO_BW_40
;
301 stat
.bw
= RATE_INFO_BW_20
;
304 if (rate
->flags
& IEEE80211_TX_RC_USE_SHORT_PREAMBLE
)
305 stat
.enc_flags
|= RX_ENC_FLAG_SHORTPRE
;
306 if (rate
->flags
& IEEE80211_TX_RC_SHORT_GI
)
307 stat
.enc_flags
|= RX_ENC_FLAG_SHORT_GI
;
309 stat
.rate_idx
= rate
->idx
;
310 if (rate
->flags
& IEEE80211_TX_RC_VHT_MCS
) {
311 stat
.encoding
= RX_ENC_VHT
;
312 stat
.rate_idx
= ieee80211_rate_get_vht_mcs(rate
);
313 stat
.nss
= ieee80211_rate_get_vht_nss(rate
);
314 } else if (rate
->flags
& IEEE80211_TX_RC_MCS
) {
315 stat
.encoding
= RX_ENC_HT
;
317 stat
.encoding
= RX_ENC_LEGACY
;
320 cur_duration
= mt76_calc_rx_airtime(dev
, &stat
, len
);
321 duration
+= cur_duration
* rate
->count
;
326 EXPORT_SYMBOL_GPL(mt76_calc_tx_airtime
);