mt76: mt7615: fix survey channel busy time

Like on mt7603, MIB status register 16 tracks CCA time, but does not
include tx time. Switch to status register 9 to includ NAV and tx
time as well.
Signed-off-by: Felix Fietkau <nbd@nbd.name>

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

@@ -53,7 +53,7 @@ void mt7615_mac_reset_counters(struct mt7615_dev *dev)
 	/* TODO: add DBDC support */
 
 	/* reset airtime counters */
-	mt76_rr(dev, MT_MIB_SDR16(0));
+	mt76_rr(dev, MT_MIB_SDR9(0));
 	mt76_rr(dev, MT_MIB_SDR36(0));
 	mt76_rr(dev, MT_MIB_SDR37(0));
 	mt76_set(dev, MT_WF_RMAC_MIB_TIME0, MT_WF_RMAC_MIB_RXTIME_CLR);
@@ -1274,7 +1274,8 @@ void mt7615_update_channel(struct mt76_dev *mdev)
 	u64 busy_time, tx_time, rx_time, obss_time;
 
 	/* TODO: add DBDC support */
-	busy_time = mt76_get_field(dev, MT_MIB_SDR16(0), MT_MIB_BUSY_MASK);
+	busy_time = mt76_get_field(dev, MT_MIB_SDR9(0),
+				   MT_MIB_SDR9_BUSY_MASK);
 	tx_time = mt76_get_field(dev, MT_MIB_SDR36(0),
 				 MT_MIB_SDR36_TXTIME_MASK);
 	rx_time = mt76_get_field(dev, MT_MIB_SDR37(0),

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

@@ -293,8 +293,11 @@
 #define MT_MIB_RTS_RETRIES_COUNT_MASK	GENMASK(31, 16)
 #define MT_MIB_RTS_COUNT_MASK		GENMASK(15, 0)
 
-#define MT_MIB_SDR16(n)			MT_WF_MIB(0x48 + ((n) << 9))
-#define MT_MIB_BUSY_MASK		GENMASK(23, 0)
+#define MT_MIB_SDR9(n)			MT_WF_MIB(0x02c + ((n) << 9))
+#define MT_MIB_SDR9_BUSY_MASK		GENMASK(23, 0)
+
+#define MT_MIB_SDR16(n)			MT_WF_MIB(0x048 + ((n) << 9))
+#define MT_MIB_SDR16_BUSY_MASK		GENMASK(23, 0)
 
 #define MT_MIB_SDR36(n)			MT_WF_MIB(0x098 + ((n) << 9))
 #define MT_MIB_SDR36_TXTIME_MASK	GENMASK(23, 0)