From: Vladimir Oltean <vladimir.oltean@xxxxxxx> [ Upstream commit 325fd36ae76a6d089983b2d2eccb41237d35b221 ] The enetc phylink .mac_config handler intends to clear the IFMODE field (bits 1:0) of the PM0_IF_MODE register, but incorrectly clears all the other fields instead. For normal operation, the bug was inconsequential, due to the fact that we write the PM0_IF_MODE register in two stages, first in phylink .mac_config (which incorrectly cleared out a bunch of stuff), then we update the speed and duplex to the correct values in phylink .mac_link_up. Judging by the code (not tested), it looks like maybe loopback mode was broken, since this is one of the settings in PM0_IF_MODE which is incorrectly cleared. Fixes: c76a97218dcb ("net: enetc: force the RGMII speed and duplex instead of operating in inband mode") Reported-by: Pavel Machek (CIP) <pavel@xxxxxxx> Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/ethernet/freescale/enetc/enetc_pf.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c index c84f6c226743..cf00709caea4 100644 --- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c +++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c @@ -541,8 +541,7 @@ static void enetc_mac_config(struct enetc_hw *hw, phy_interface_t phy_mode) if (phy_interface_mode_is_rgmii(phy_mode)) { val = enetc_port_rd(hw, ENETC_PM0_IF_MODE); - val &= ~ENETC_PM0_IFM_EN_AUTO; - val &= ENETC_PM0_IFM_IFMODE_MASK; + val &= ~(ENETC_PM0_IFM_EN_AUTO | ENETC_PM0_IFM_IFMODE_MASK); val |= ENETC_PM0_IFM_IFMODE_GMII | ENETC_PM0_IFM_RG; enetc_port_wr(hw, ENETC_PM0_IF_MODE, val); } -- 2.33.0