wifi: mt76: mt7915: deal with special variant of mt7916

A variant of mt7916 supports up to 3 tx/rx paths but with only
2 spatial streams. An example usage of the 3rd path is to server as
an auxiliary for beamforming.
In order to deal with this case, this patch reworks some parts to
correctly use paths or streams.
Signed-off-by: Peter Chiu <chui-hao.chiu@mediatek.com>
Signed-off-by: Shayne Chen <shayne.chen@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -700,13 +700,13 @@ mt7915_init_hardware(struct mt7915_dev *dev, struct mt7915_phy *phy2)
 
 void mt7915_set_stream_vht_txbf_caps(struct mt7915_phy *phy)
 {
-	int nss;
+	int sts;
 	u32 *cap;
 
 	if (!phy->mt76->cap.has_5ghz)
 		return;
 
-	nss = hweight8(phy->mt76->chainmask);
+	sts = hweight8(phy->mt76->chainmask);
 	cap = &phy->mt76->sband_5g.sband.vht_cap.cap;
 
 	*cap |= IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE |
@@ -717,28 +717,27 @@ void mt7915_set_stream_vht_txbf_caps(struct mt7915_phy *phy)
 		  IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE |
 		  IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE);
 
-	if (nss < 2)
+	if (sts < 2)
 		return;
 
 	*cap |= IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE |
 		IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE |
 		FIELD_PREP(IEEE80211_VHT_CAP_SOUNDING_DIMENSIONS_MASK,
-			   nss - 1);
+			   sts - 1);
 }
 
 static void
-mt7915_set_stream_he_txbf_caps(struct mt7915_dev *dev,
-			       struct ieee80211_sta_he_cap *he_cap,
-			       int vif, int nss)
+mt7915_set_stream_he_txbf_caps(struct mt7915_phy *phy,
+			       struct ieee80211_sta_he_cap *he_cap, int vif)
 {
+	struct mt7915_dev *dev = phy->dev;
 	struct ieee80211_he_cap_elem *elem = &he_cap->he_cap_elem;
-	u8 c, nss_160;
+	int sts = hweight8(phy->mt76->chainmask);
+	u8 c, sts_160 = sts;
 
-	/* Can do 1/2 of NSS streams in 160Mhz mode for mt7915 */
+	/* Can do 1/2 of STS in 160Mhz mode for mt7915 */
 	if (is_mt7915(&dev->mt76) && !dev->dbdc_support)
-		nss_160 = nss / 2;
-	else
-		nss_160 = nss;
+		sts_160 /= 2;
 
 #ifdef CONFIG_MAC80211_MESH
 	if (vif == NL80211_IFTYPE_MESH_POINT)
@@ -778,11 +777,11 @@ mt7915_set_stream_he_txbf_caps(struct mt7915_dev *dev,
 
 	elem->phy_cap_info[6] |= c;
 
-	if (nss < 2)
+	if (sts < 2)
 		return;
 
 	/* the maximum cap is 4 x 3, (Nr, Nc) = (3, 2) */
-	elem->phy_cap_info[7] |= min_t(int, nss - 1, 2) << 3;
+	elem->phy_cap_info[7] |= min_t(int, sts - 1, 2) << 3;
 
 	if (vif != NL80211_IFTYPE_AP)
 		return;
@@ -791,12 +790,12 @@ mt7915_set_stream_he_txbf_caps(struct mt7915_dev *dev,
 	elem->phy_cap_info[4] |= IEEE80211_HE_PHY_CAP4_MU_BEAMFORMER;
 
 	/* num_snd_dim
-	 * for mt7915, max supported nss is 2 for bw > 80MHz
+	 * for mt7915, max supported sts is 2 for bw > 80MHz
 	 */
 	c = FIELD_PREP(IEEE80211_HE_PHY_CAP5_BEAMFORMEE_NUM_SND_DIM_UNDER_80MHZ_MASK,
-		       nss - 1) |
+		       sts - 1) |
 	    FIELD_PREP(IEEE80211_HE_PHY_CAP5_BEAMFORMEE_NUM_SND_DIM_ABOVE_80MHZ_MASK,
-		       nss_160 - 1);
+		       sts_160 - 1);
 	elem->phy_cap_info[5] |= c;
 
 	c = IEEE80211_HE_PHY_CAP6_TRIG_SU_BEAMFORMING_FB |
@@ -836,7 +835,7 @@ mt7915_init_he_caps(struct mt7915_phy *phy, enum nl80211_band band,
 		    struct ieee80211_sband_iftype_data *data)
 {
 	struct mt7915_dev *dev = phy->dev;
-	int i, idx = 0, nss = hweight8(phy->mt76->chainmask);
+	int i, idx = 0, nss = hweight8(phy->mt76->antenna_mask);
 	u16 mcs_map = 0;
 	u16 mcs_map_160 = 0;
 	u8 nss_160;
@@ -969,7 +968,7 @@ mt7915_init_he_caps(struct mt7915_phy *phy, enum nl80211_band band,
 		he_mcs->rx_mcs_80p80 = cpu_to_le16(mcs_map_160);
 		he_mcs->tx_mcs_80p80 = cpu_to_le16(mcs_map_160);
 
-		mt7915_set_stream_he_txbf_caps(dev, he_cap, i, nss);
+		mt7915_set_stream_he_txbf_caps(phy, he_cap, i);
 
 		memset(he_cap->ppe_thres, 0, sizeof(he_cap->ppe_thres));
 		if (he_cap_elem->phy_cap_info[6] &

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

@@ -953,7 +953,7 @@ mt7915_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
 	struct mt7915_dev *dev = mt7915_hw_dev(hw);
 	struct mt7915_phy *phy = mt7915_hw_phy(hw);
 	int max_nss = hweight8(hw->wiphy->available_antennas_tx);
-	bool ext_phy = phy != &dev->phy;
+	u8 chainshift = dev->chainshift;
 
 	if (!tx_ant || tx_ant != rx_ant || ffs(tx_ant) > max_nss)
 		return -EINVAL;
@@ -965,10 +965,11 @@ mt7915_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
 
 	phy->mt76->antenna_mask = tx_ant;
 
-	if (ext_phy)
-		tx_ant <<= dev->chainshift;
-
-	phy->mt76->chainmask = tx_ant;
+	/* handle a variant of mt7916 which has 3T3R but nss2 on 5 GHz band */
+	if (is_mt7916(&dev->mt76) && phy->band_idx && hweight8(tx_ant) == max_nss)
+		phy->mt76->chainmask = (dev->chainmask >> chainshift) << chainshift;
+	else
+		phy->mt76->chainmask = tx_ant << (chainshift * phy->band_idx);
 
 	mt76_set_stream_caps(phy->mt76, true);
 	mt7915_set_stream_vht_txbf_caps(phy);

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

@@ -485,7 +485,7 @@ static void
 mt7915_mcu_bss_ra_tlv(struct sk_buff *skb, struct ieee80211_vif *vif,
 		      struct mt7915_phy *phy)
 {
-	int max_nss = hweight8(phy->mt76->chainmask);
+	int max_nss = hweight8(phy->mt76->antenna_mask);
 	struct bss_info_ra *ra;
 	struct tlv *tlv;
 
@@ -2617,8 +2617,8 @@ int mt7915_mcu_set_chan_info(struct mt7915_phy *phy, int cmd)
 		u8 control_ch;
 		u8 center_ch;
 		u8 bw;
-		u8 tx_streams_num;
-		u8 rx_streams;	/* mask or num */
+		u8 tx_path_num;
+		u8 rx_path;	/* mask or num */
 		u8 switch_reason;
 		u8 band_idx;
 		u8 center_ch2;	/* for 80+80 only */
@@ -2634,8 +2634,8 @@ int mt7915_mcu_set_chan_info(struct mt7915_phy *phy, int cmd)
 		.control_ch = chandef->chan->hw_value,
 		.center_ch = ieee80211_frequency_to_channel(freq1),
 		.bw = mt76_connac_chan_bw(chandef),
-		.tx_streams_num = hweight8(phy->mt76->antenna_mask),
-		.rx_streams = phy->mt76->antenna_mask,
+		.tx_path_num = hweight16(phy->mt76->chainmask),
+		.rx_path = phy->mt76->chainmask >> (dev->chainshift * phy->band_idx),
 		.band_idx = phy->band_idx,
 		.channel_band = ch_band[chandef->chan->band],
 	};
@@ -2645,8 +2645,8 @@ int mt7915_mcu_set_chan_info(struct mt7915_phy *phy, int cmd)
 	    (phy->mt76->test.state == MT76_TM_STATE_TX_FRAMES ||
 	     phy->mt76->test.state == MT76_TM_STATE_RX_FRAMES ||
 	     phy->mt76->test.state == MT76_TM_STATE_TX_CONT)) {
-		req.tx_streams_num = fls(phy->mt76->test.tx_antenna_mask);
-		req.rx_streams = phy->mt76->test.tx_antenna_mask;
+		req.tx_path_num = fls(phy->mt76->test.tx_antenna_mask);
+		req.rx_path = phy->mt76->test.tx_antenna_mask;
 
 		if (phy != &dev->phy)
 			req.rx_streams >>= dev->chainshift;
@@ -2665,7 +2665,7 @@ int mt7915_mcu_set_chan_info(struct mt7915_phy *phy, int cmd)
 		req.switch_reason = CH_SWITCH_NORMAL;
 
 	if (cmd == MCU_EXT_CMD(CHANNEL_SWITCH))
-		req.rx_streams = hweight8(req.rx_streams);
+		req.rx_path = hweight8(req.rx_path);
 
 	if (chandef->width == NL80211_CHAN_WIDTH_80P80) {
 		int freq2 = chandef->center_freq2;