[PATCH 5.5 070/151] net: dsa: mv88e6xxx: Add missing mask of ATU occupancy register

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

From: Andrew Lunn <andrew@xxxxxxx>

[ Upstream commit 012fc74517b25177dfede2ed45cd108258564e4a ]

Only the bottom 12 bits contain the ATU bin occupancy statistics. The
upper bits need masking off.

Fixes: e0c69ca7dfbb ("net: dsa: mv88e6xxx: Add ATU occupancy via devlink resources")
Signed-off-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/dsa/mv88e6xxx/chip.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -2762,6 +2762,8 @@ static u64 mv88e6xxx_devlink_atu_bin_get
 		goto unlock;
 	}
 
+	occupancy &= MV88E6XXX_G2_ATU_STATS_MASK;
+
 unlock:
 	mv88e6xxx_reg_unlock(chip);