diff --git a/drivers/phy/microchip/lan966x_serdes.c b/drivers/phy/microchip/lan966x_serdes.c
index 262bb616b4bb684a8428dd5c5b87419eb9826669..c0b80a176387e0944caa069c57bb803403106599 100644
--- a/drivers/phy/microchip/lan966x_serdes.c
+++ b/drivers/phy/microchip/lan966x_serdes.c
@@ -392,6 +392,10 @@ static int serdes_set_mode(struct phy *phy, enum phy_mode mode, int submode)
 	if (mode != PHY_MODE_ETHERNET)
 		return -EOPNOTSUPP;
 
+	if (submode == PHY_INTERFACE_MODE_1000BASEX ||
+	    submode == PHY_INTERFACE_MODE_2500BASEX)
+		submode = PHY_INTERFACE_MODE_SGMII;
+
 	for (i = 0; i < ARRAY_SIZE(lan966x_serdes_muxes); i++) {
 		if (macro->idx != lan966x_serdes_muxes[i].idx ||
 		    mode != lan966x_serdes_muxes[i].mode ||