[PATCH 5.5 28/65] net: stmmac: xgmac: Fix VLAN register handling

From: Greg Kroah-Hartman
Date: Mon Apr 20 2020 - 08:40:58 EST


From: Jose Abreu <Jose.Abreu@xxxxxxxxxxxx>

commit 21f64e72e7073199a6f8d7d8efe52cd814d7d665 upstream.

Commit 907a076881f1, forgot that we need to clear old values of
XGMAC_VLAN_TAG register when we switch from VLAN perfect matching to
HASH matching.

Fix it.

Fixes: 907a076881f1 ("net: stmmac: xgmac: fix incorrect XGMAC_VLAN_TAG register writting")
Signed-off-by: Jose Abreu <Jose.Abreu@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c | 11 +++++++++++
1 file changed, 11 insertions(+)

--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
@@ -576,8 +576,13 @@ static void dwxgmac2_update_vlan_hash(st
value |= XGMAC_VLAN_EDVLP;
value |= XGMAC_VLAN_ESVL;
value |= XGMAC_VLAN_DOVLTC;
+ } else {
+ value &= ~XGMAC_VLAN_EDVLP;
+ value &= ~XGMAC_VLAN_ESVL;
+ value &= ~XGMAC_VLAN_DOVLTC;
}

+ value &= ~XGMAC_VLAN_VID;
writel(value, ioaddr + XGMAC_VLAN_TAG);
} else if (perfect_match) {
u32 value = readl(ioaddr + XGMAC_PACKET_FILTER);
@@ -588,13 +593,19 @@ static void dwxgmac2_update_vlan_hash(st

value = readl(ioaddr + XGMAC_VLAN_TAG);

+ value &= ~XGMAC_VLAN_VTHM;
value |= XGMAC_VLAN_ETV;
if (is_double) {
value |= XGMAC_VLAN_EDVLP;
value |= XGMAC_VLAN_ESVL;
value |= XGMAC_VLAN_DOVLTC;
+ } else {
+ value &= ~XGMAC_VLAN_EDVLP;
+ value &= ~XGMAC_VLAN_ESVL;
+ value &= ~XGMAC_VLAN_DOVLTC;
}

+ value &= ~XGMAC_VLAN_VID;
writel(value | perfect_match, ioaddr + XGMAC_VLAN_TAG);
} else {
u32 value = readl(ioaddr + XGMAC_PACKET_FILTER);