mt76: mt7915: query station rx rate from firmware

When per-packet rate reporting is enabled, the hardware can get stuck under
some conditions. It self-recovers quickly, but in practice this leads to
reduced performance.
In order to avoid running into this issue, disable per-packet rate reporting
by default and query the rx rate from firmware instead, unless monitor mode
is enabled.
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7915/init.c

@@ -43,8 +43,8 @@ static void mt7915_mac_init(struct mt7915_dev *dev)
 
 	mt76_rmw_field(dev, MT_DMA_DCR0, MT_DMA_DCR0_MAX_RX_LEN, 1536);
 	mt76_rmw_field(dev, MT_MDP_DCR1, MT_MDP_DCR1_MAX_RX_LEN, 1536);
-	/* enable rx rate report */
-	mt76_set(dev, MT_DMA_DCR0, MT_DMA_DCR0_RXD_G5_EN);
+	/* disable rx rate report by default due to hw issues */
+	mt76_clear(dev, MT_DMA_DCR0, MT_DMA_DCR0_RXD_G5_EN);
 	/* disable hardware de-agg */
 	mt76_clear(dev, MT_MDP_DCR0, MT_MDP_DCR0_DAMSDU_EN);
 

drivers/net/wireless/mediatek/mt76/mt7915/main.c

@@ -362,11 +362,14 @@ static int mt7915_config(struct ieee80211_hw *hw, u32 changed)
 	mutex_lock(&dev->mt76.mutex);
 
 	if (changed & IEEE80211_CONF_CHANGE_MONITOR) {
-		if (!(hw->conf.flags & IEEE80211_CONF_MONITOR))
+		bool enabled = !!(hw->conf.flags & IEEE80211_CONF_MONITOR);
+
+		if (!enabled)
 			phy->rxfilter |= MT_WF_RFCR_DROP_OTHER_UC;
 		else
 			phy->rxfilter &= ~MT_WF_RFCR_DROP_OTHER_UC;
 
+		mt76_rmw_field(dev, MT_DMA_DCR0, MT_DMA_DCR0_RXD_G5_EN, enabled);
 		mt76_wr(dev, MT_WF_RFCR(band), phy->rxfilter);
 	}
 
@@ -794,9 +797,13 @@ static void mt7915_sta_statistics(struct ieee80211_hw *hw,
 				  struct ieee80211_sta *sta,
 				  struct station_info *sinfo)
 {
+	struct mt7915_phy *phy = mt7915_hw_phy(hw);
 	struct mt7915_sta *msta = (struct mt7915_sta *)sta->drv_priv;
 	struct mt7915_sta_stats *stats = &msta->stats;
 
+	if (mt7915_mcu_get_rx_rate(phy, vif, sta, &sinfo->rxrate) == 0)
+		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_BITRATE);
+
 	if (!stats->tx_rate.legacy && !stats->tx_rate.flags)
 		return;
 

drivers/net/wireless/mediatek/mt76/mt7915/mcu.c

@@ -3404,3 +3404,97 @@ int mt7915_mcu_add_obss_spr(struct mt7915_dev *dev, struct ieee80211_vif *vif,
 	return mt76_mcu_send_msg(&dev->mt76, MCU_EXT_CMD_SET_SPR, &req,
 				 sizeof(req), true);
 }
+
+int mt7915_mcu_get_rx_rate(struct mt7915_phy *phy, struct ieee80211_vif *vif,
+			   struct ieee80211_sta *sta, struct rate_info *rate)
+{
+	struct mt7915_vif *mvif = (struct mt7915_vif *)vif->drv_priv;
+	struct mt7915_sta *msta = (struct mt7915_sta *)sta->drv_priv;
+	struct mt7915_dev *dev = phy->dev;
+	struct mt76_phy *mphy = phy->mt76;
+	struct {
+		u8 category;
+		u8 band;
+		__le16 wcid;
+	} __packed req = {
+		.category = MCU_PHY_STATE_CONTENTION_RX_RATE,
+		.band = mvif->band_idx,
+		.wcid = cpu_to_le16(msta->wcid.idx),
+	};
+	struct ieee80211_supported_band *sband;
+	struct mt7915_mcu_phy_rx_info *res;
+	struct sk_buff *skb;
+	u16 flags = 0;
+	int ret;
+	int i;
+
+	ret = mt76_mcu_send_and_get_msg(&dev->mt76, MCU_EXT_CMD_PHY_STAT_INFO,
+					&req, sizeof(req), true, &skb);
+	if (ret)
+		return ret;
+
+	res = (struct mt7915_mcu_phy_rx_info *)skb->data;
+
+	rate->mcs = res->rate;
+	rate->nss = res->nsts + 1;
+
+	switch (res->mode) {
+	case MT_PHY_TYPE_CCK:
+	case MT_PHY_TYPE_OFDM:
+		if (mphy->chandef.chan->band == NL80211_BAND_5GHZ)
+			sband = &mphy->sband_5g.sband;
+		else
+			sband = &mphy->sband_2g.sband;
+
+		for (i = 0; i < sband->n_bitrates; i++) {
+			if (rate->mcs != (sband->bitrates[i].hw_value & 0xf))
+				continue;
+
+			rate->legacy = sband->bitrates[i].bitrate;
+			break;
+		}
+		break;
+	case MT_PHY_TYPE_HT:
+	case MT_PHY_TYPE_HT_GF:
+		rate->mcs += (rate->nss - 1) * 8;
+		flags |= RATE_INFO_FLAGS_MCS;
+
+		if (res->gi)
+			flags |= RATE_INFO_FLAGS_SHORT_GI;
+		break;
+	case MT_PHY_TYPE_VHT:
+		flags |= RATE_INFO_FLAGS_VHT_MCS;
+
+		if (res->gi)
+			flags |= RATE_INFO_FLAGS_SHORT_GI;
+		break;
+	case MT_PHY_TYPE_HE_SU:
+	case MT_PHY_TYPE_HE_EXT_SU:
+	case MT_PHY_TYPE_HE_TB:
+	case MT_PHY_TYPE_HE_MU:
+		rate->he_gi = res->gi;
+
+		flags |= RATE_INFO_FLAGS_HE_MCS;
+		break;
+	default:
+		break;
+	}
+	rate->flags = flags;
+
+	switch (res->bw) {
+	case IEEE80211_STA_RX_BW_160:
+		rate->bw = RATE_INFO_BW_160;
+		break;
+	case IEEE80211_STA_RX_BW_80:
+		rate->bw = RATE_INFO_BW_80;
+		break;
+	case IEEE80211_STA_RX_BW_40:
+		rate->bw = RATE_INFO_BW_40;
+		break;
+	default:
+		rate->bw = RATE_INFO_BW_20;
+		break;
+	}
+
+	return 0;
+}

drivers/net/wireless/mediatek/mt76/mt7915/mcu.h

@@ -153,6 +153,18 @@ struct mt7915_mcu_ra_info {
 	u8 prob_down_pending;
 } __packed;
 
+
+struct mt7915_mcu_phy_rx_info {
+	u8 category;
+	u8 rate;
+	u8 mode;
+	u8 nsts;
+	u8 gi;
+	u8 coding;
+	u8 stbc;
+	u8 bw;
+};
+
 #define MT_RA_RATE_NSS			GENMASK(8, 6)
 #define MT_RA_RATE_MCS			GENMASK(3, 0)
 #define MT_RA_RATE_TX_MODE		GENMASK(12, 9)
@@ -217,6 +229,7 @@ enum {
 	MCU_EXT_CMD_FW_DBG_CTRL = 0x95,
 	MCU_EXT_CMD_SET_RDD_TH = 0x9d,
 	MCU_EXT_CMD_SET_SPR = 0xa8,
+	MCU_EXT_CMD_PHY_STAT_INFO = 0xad,
 };
 
 enum {
@@ -250,6 +263,14 @@ enum {
 	EE_FORMAT_MULTIPLE,
 };
 
+enum {
+	MCU_PHY_STATE_TX_RATE,
+	MCU_PHY_STATE_RX_RATE,
+	MCU_PHY_STATE_RSSI,
+	MCU_PHY_STATE_CONTENTION_RX_RATE,
+	MCU_PHY_STATE_OFDMLQ_CNINFO,
+};
+
 #define STA_TYPE_STA			BIT(0)
 #define STA_TYPE_AP			BIT(1)
 #define STA_TYPE_ADHOC			BIT(2)

drivers/net/wireless/mediatek/mt76/mt7915/mt7915.h

@@ -321,6 +321,8 @@ int mt7915_mcu_set_radar_th(struct mt7915_dev *dev, int index,
 			    const struct mt7915_dfs_pattern *pattern);
 int mt7915_mcu_get_rate_info(struct mt7915_dev *dev, u32 cmd, u16 wlan_idx);
 int mt7915_mcu_get_temperature(struct mt7915_dev *dev, int index);
+int mt7915_mcu_get_rx_rate(struct mt7915_phy *phy, struct ieee80211_vif *vif,
+			   struct ieee80211_sta *sta, struct rate_info *rate);
 int mt7915_mcu_rdd_cmd(struct mt7915_dev *dev, enum mt7915_rdd_cmd cmd,
 		       u8 index, u8 rx_sel, u8 val);
 int mt7915_mcu_fw_log_2_host(struct mt7915_dev *dev, u8 ctrl);