[PATCH 5.5 331/367] net: stmmac: xgmac: fix incorrect XGMAC_VLAN_TAG register writting
From: Greg Kroah-Hartman
Date: Mon Feb 10 2020 - 07:54:34 EST
From: Ong Boon Leong <boon.leong.ong@xxxxxxxxx>
[ Upstream commit 907a076881f171254219faad05f46ac5baabedfb ]
We should always do a read of current value of XGMAC_VLAN_TAG instead of
directly overwriting the register value.
Fixes: 3cd1cfcba26e2 ("net: stmmac: Implement VLAN Hash Filtering in XGMAC")
Signed-off-by: Ong Boon Leong <boon.leong.ong@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
@@ -569,7 +569,9 @@ static void dwxgmac2_update_vlan_hash(st
writel(value, ioaddr + XGMAC_PACKET_FILTER);
- value = XGMAC_VLAN_VTHM | XGMAC_VLAN_ETV;
+ value = readl(ioaddr + XGMAC_VLAN_TAG);
+
+ value |= XGMAC_VLAN_VTHM | XGMAC_VLAN_ETV;
if (is_double) {
value |= XGMAC_VLAN_EDVLP;
value |= XGMAC_VLAN_ESVL;
@@ -584,7 +586,9 @@ static void dwxgmac2_update_vlan_hash(st
writel(value, ioaddr + XGMAC_PACKET_FILTER);
- value = XGMAC_VLAN_ETV;
+ value = readl(ioaddr + XGMAC_VLAN_TAG);
+
+ value |= XGMAC_VLAN_ETV;
if (is_double) {
value |= XGMAC_VLAN_EDVLP;
value |= XGMAC_VLAN_ESVL;