path: root/Revert-mt76-rely-on-mac80211-utility-routines-to-com.patch

From 83b962a61249259039e2af60441bac9c017ab6c2 Mon Sep 17 00:00:00 2001
From: Tomasz Maciej Nowak <tomek_n@o2.pl>
Date: Fri, 19 Jun 2020 16:52:56 +0200
Subject: [PATCH] Revert "mt76: rely on mac80211 utility routines to compute
 airtime"

This reverts commit 29fec3a9b0b446036198860f0e9a9caffd9f8103.
---
 Makefile      |   2 +-
 airtime.c     | 326 ++++++++++++++++++++++++++++++++++++++++++++++++++
 mac80211.c    |  10 +-
 mt76.h        |   4 +
 mt76x02_mac.c |   2 +-
 5 files changed, 333 insertions(+), 11 deletions(-)
 create mode 100644 airtime.c

diff --git a/Makefile b/Makefile
index ccb41729f726..ec1121507191 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@ obj-$(CONFIG_MT76x02_USB) += mt76x02-usb.o
 
 mt76-y := \
 	mmio.o util.o trace.o dma.o mac80211.o debugfs.o eeprom.o \
-	tx.o agg-rx.o mcu.o
+	tx.o agg-rx.o mcu.o airtime.o
 
 mt76-$(CONFIG_PCI) += pci.o
 
diff --git a/airtime.c b/airtime.c
new file mode 100644
index 000000000000..a4a785467748
--- /dev/null
+++ b/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);
diff --git a/mac80211.c b/mac80211.c
index d8533d0c6e81..f4dd010ac73f 100644
--- a/mac80211.c
+++ b/mac80211.c
@@ -758,18 +758,10 @@ mt76_airtime_report(struct mt76_dev *dev, struct mt76_rx_status *status,
 		    int len)
 {
 	struct mt76_wcid *wcid = status->wcid;
-	struct ieee80211_rx_status info = {
-		.enc_flags = status->enc_flags,
-		.rate_idx = status->rate_idx,
-		.encoding = status->encoding,
-		.band = status->band,
-		.nss = status->nss,
-		.bw = status->bw,
-	};
 	struct ieee80211_sta *sta;
 	u32 airtime;
 
-	airtime = ieee80211_calc_rx_airtime(dev->hw, &info, len);
+	airtime = mt76_calc_rx_airtime(dev, status, len);
 	spin_lock(&dev->cc_lock);
 	dev->cur_cc_bss_rx += airtime;
 	spin_unlock(&dev->cc_lock);
diff --git a/mt76.h b/mt76.h
index d50871653de1..3476efe60fdb 100644
--- a/mt76.h
+++ b/mt76.h
@@ -886,6 +886,8 @@ void mt76_sw_scan(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 		  const u8 *mac);
 void mt76_sw_scan_complete(struct ieee80211_hw *hw,
 			   struct ieee80211_vif *vif);
+u32 mt76_calc_tx_airtime(struct mt76_dev *dev, struct ieee80211_tx_info *info,
+			 int len);
 
 /* internal */
 static inline struct ieee80211_hw *
@@ -910,6 +912,8 @@ void mt76_rx_complete(struct mt76_dev *dev, struct sk_buff_head *frames,
 void mt76_rx_poll_complete(struct mt76_dev *dev, enum mt76_rxq_id q,
 			   struct napi_struct *napi);
 void mt76_rx_aggr_reorder(struct sk_buff *skb, struct sk_buff_head *frames);
+u32 mt76_calc_rx_airtime(struct mt76_dev *dev, struct mt76_rx_status *status,
+			 int len);
 
 /* usb */
 static inline bool mt76u_urb_error(struct urb *urb)
diff --git a/mt76x02_mac.c b/mt76x02_mac.c
index e4e03beabe43..7d4e0c394e94 100644
--- a/mt76x02_mac.c
+++ b/mt76x02_mac.c
@@ -634,7 +634,7 @@ void mt76x02_send_tx_status(struct mt76x02_dev *dev,
 	if (!len)
 		goto out;
 
-	duration = ieee80211_calc_tx_airtime(mt76_hw(dev), &info, len);
+	duration = mt76_calc_tx_airtime(&dev->mt76, &info, len);
 
 	spin_lock_bh(&dev->mt76.cc_lock);
 	dev->tx_airtime += duration;
-- 
2.27.0