[PATCH AUTOSEL 5.1 029/219] net: stmmac: dwmac4/5: Clear unused address entries

[Sasha Levin]

From: Jose Abreu <jose.ab...@synopsys.com>

[ Upstream commit 0620ec6c62a5a07625b65f699adc5d1b90394ee6 ]

In case we don't use a given address entry we need to clear it because
it could contain previous values that are no longer valid.

Found out while running stmmac selftests.

Signed-off-by: Jose Abreu <joab...@synopsys.com>
Cc: Joao Pinto <jpi...@synopsys.com>
Cc: David S. Miller <da...@davemloft.net>
Cc: Giuseppe Cavallaro <peppe.cavall...@st.com>
Cc: Alexandre Torgue <alexandre.tor...@st.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c 
b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index 7e5d5db0d516..a2f3db39221e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -444,14 +444,20 @@ static void dwmac4_set_filter(struct mac_device_info *hw,
                 * are required
                 */
                value |= GMAC_PACKET_FILTER_PR;
-       } else if (!netdev_uc_empty(dev)) {
-               int reg = 1;
+       } else {
                struct netdev_hw_addr *ha;
+               int reg = 1;
 
                netdev_for_each_uc_addr(ha, dev) {
                        dwmac4_set_umac_addr(hw, ha->addr, reg);
                        reg++;
                }
+
+               while (reg <= GMAC_MAX_PERFECT_ADDRESSES) {
+                       writel(0, ioaddr + GMAC_ADDR_HIGH(reg));
+                       writel(0, ioaddr + GMAC_ADDR_LOW(reg));
+                       reg++;
+               }
        }
 
        writel(value, ioaddr + GMAC_PACKET_FILTER);
-- 
2.20.1