mt76: mt7615: read {tx,rx} mask from eeprom

Parse configured {tx,rx} mask from eeprom data instead of just setting it
to four tx-rx streams

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7615/eeprom.c

@@ -93,6 +93,7 @@ static int mt7615_check_eeprom(struct mt76_dev *dev)
 static void mt7615_eeprom_parse_hw_cap(struct mt7615_dev *dev)
 {
 	u8 val, *eeprom = dev->mt76.eeprom.data;
+	u8 tx_mask, rx_mask, max_nss;
 
 	val = FIELD_GET(MT_EE_NIC_WIFI_CONF_BAND_SEL,
 			eeprom[MT_EE_WIFI_CONF]);
@@ -108,6 +109,23 @@ static void mt7615_eeprom_parse_hw_cap(struct mt7615_dev *dev)
 		dev->mt76.cap.has_5ghz = true;
 		break;
 	}
+
+	/* read tx-rx mask from eeprom */
+	val = mt76_rr(dev, MT_TOP_STRAP_STA);
+	max_nss = val & MT_TOP_3NSS ? 3 : 4;
+
+	rx_mask =  FIELD_GET(MT_EE_NIC_CONF_RX_MASK,
+			     eeprom[MT_EE_NIC_CONF_0]);
+	if (!rx_mask || rx_mask > max_nss)
+		rx_mask = max_nss;
+
+	tx_mask =  FIELD_GET(MT_EE_NIC_CONF_TX_MASK,
+			     eeprom[MT_EE_NIC_CONF_0]);
+	if (!tx_mask || tx_mask > max_nss)
+		tx_mask = max_nss;
+
+	dev->mt76.chainmask = tx_mask << 8 | rx_mask;
+	dev->mt76.antenna_mask = BIT(tx_mask) - 1;
 }
 
 int mt7615_eeprom_get_power_index(struct mt7615_dev *dev,

drivers/net/wireless/mediatek/mt76/mt7615/eeprom.h

@@ -24,6 +24,9 @@ enum mt7615_eeprom_field {
 	__MT_EE_MAX =				0x3bf
 };
 
+#define MT_EE_NIC_CONF_TX_MASK			GENMASK(7, 4)
+#define MT_EE_NIC_CONF_RX_MASK			GENMASK(3, 0)
+
 #define MT_EE_NIC_CONF_TSSI_2G			BIT(5)
 #define MT_EE_NIC_CONF_TSSI_5G			BIT(6)
 

drivers/net/wireless/mediatek/mt76/mt7615/init.c

@@ -303,8 +303,6 @@ int mt7615_register_device(struct mt7615_dev *dev)
 			IEEE80211_VHT_CAP_MAX_MPDU_LENGTH_11454 |
 			IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK |
 			IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ;
-	dev->mt76.chainmask = 0x404;
-	dev->mt76.antenna_mask = 0xf;
 	dev->dfs_state = -1;
 
 	ret = mt76_register_device(&dev->mt76, true, mt7615_rates,

drivers/net/wireless/mediatek/mt76/mt7615/regs.h

@@ -6,6 +6,8 @@
 
 #define MT_HW_REV			0x1000
 #define MT_HW_CHIPID			0x1008
+#define MT_TOP_STRAP_STA		0x1010
+#define MT_TOP_3NSS			BIT(24)
 #define MT_TOP_MISC2			0x1134
 #define MT_TOP_MISC2_FW_STATE		GENMASK(2, 0)