wifi: mt76: connac: enable critical packet mode support for mt7992

For mt7992 chipsets, critical packet mode should be properly configured
to let the HW SDO module correctly fill the AC queue in TX descriptors of
some higher priority packets such as ARP and ICMP.
Without this patch, HW queues may hang when running MU traffic.
Signed-off-by: Howard Hsu <howard-yh.hsu@mediatek.com>
Signed-off-by: Shayne Chen <shayne.chen@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.h

@@ -1220,6 +1220,7 @@ enum {
 	MCU_EXT_CMD_TXDPD_CAL = 0x60,
 	MCU_EXT_CMD_CAL_CACHE = 0x67,
 	MCU_EXT_CMD_RED_ENABLE = 0x68,
+	MCU_EXT_CMD_CP_SUPPORT = 0x75,
 	MCU_EXT_CMD_SET_RADAR_TH = 0x7c,
 	MCU_EXT_CMD_SET_RDD_PATTERN = 0x7d,
 	MCU_EXT_CMD_MWDS_SUPPORT = 0x80,

drivers/net/wireless/mediatek/mt76/mt7996/main.c

@@ -35,6 +35,14 @@ int mt7996_run(struct ieee80211_hw *hw)
 		ret = mt7996_mcu_set_hdr_trans(dev, true);
 		if (ret)
 			goto out;
+
+		if (is_mt7992(&dev->mt76)) {
+			u8 queue = mt76_connac_lmac_mapping(IEEE80211_AC_VI);
+
+			ret = mt7996_mcu_cp_support(dev, queue);
+			if (ret)
+				goto out;
+		}
 	}
 
 	mt7996_mac_enable_nf(dev, phy->mt76->band_idx);

drivers/net/wireless/mediatek/mt76/mt7996/mcu.c

@@ -4533,3 +4533,16 @@ int mt7996_mcu_set_txpower_sku(struct mt7996_phy *phy)
 	return mt76_mcu_skb_send_msg(&dev->mt76, skb,
 				     MCU_WM_UNI_CMD(TXPOWER), true);
 }
+
+int mt7996_mcu_cp_support(struct mt7996_dev *dev, u8 mode)
+{
+	__le32 cp_mode;
+
+	if (mode < mt76_connac_lmac_mapping(IEEE80211_AC_BE) ||
+	    mode > mt76_connac_lmac_mapping(IEEE80211_AC_VO))
+		return -EINVAL;
+
+	cp_mode = cpu_to_le32(mode);
+	return mt76_mcu_send_msg(&dev->mt76, MCU_WA_EXT_CMD(CP_SUPPORT),
+				 &cp_mode, sizeof(cp_mode), true);
+}

drivers/net/wireless/mediatek/mt76/mt7996/mt7996.h

@@ -613,6 +613,7 @@ int mt7996_mcu_bcn_prot_enable(struct mt7996_dev *dev, struct ieee80211_vif *vif
 int mt7996_mcu_wtbl_update_hdr_trans(struct mt7996_dev *dev,
 				     struct ieee80211_vif *vif,
 				     struct ieee80211_sta *sta);
+int mt7996_mcu_cp_support(struct mt7996_dev *dev, u8 mode);
 #ifdef CONFIG_MAC80211_DEBUGFS
 void mt7996_sta_add_debugfs(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 			    struct ieee80211_sta *sta, struct dentry *dir);