Subject: [PATCH AUTOSEL 5.5 078/106] net: stmmac: xgmac: Fix VLAN register handling

From: Sasha Levin <[email-masked]>
Date: Wed, 15 Apr 2020 07:41:58 -0400

From: Jose Abreu <[email-masked]>

[ Upstream commit 21f64e72e7073199a6f8d7d8efe52cd814d7d665 ]

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 <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c
index e9bf54a579df6..f0b9c43f6e31e 100644
--- 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(struct mac_device_info *hw, u32 hash,
 			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(struct mac_device_info *hw, u32 hash,
 
 		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);
-- 
2.20.1