diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index 5ba1e0d71c68..9939ccafb556 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -507,6 +507,11 @@ struct bufdesc_ex {
 /* i.MX6Q adds pm_qos support */
 #define FEC_QUIRK_HAS_PMQOS			BIT(23)
 
+/* Not all FEC hardware block MDIOs support accesses in C45 mode.
+ * Older blocks in the ColdFire parts do not support it.
+ */
+#define FEC_QUIRK_HAS_MDIO_C45		BIT(24)
+
 struct bufdesc_prop {
 	int qid;
 	/* Address of Rx and Tx buffers */
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index f3b16a6673e2..160c1b3525f5 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -100,18 +100,19 @@ struct fec_devinfo {
 
 static const struct fec_devinfo fec_imx25_info = {
 	.quirks = FEC_QUIRK_USE_GASKET | FEC_QUIRK_MIB_CLEAR |
-		  FEC_QUIRK_HAS_FRREG,
+		  FEC_QUIRK_HAS_FRREG | FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_imx27_info = {
-	.quirks = FEC_QUIRK_MIB_CLEAR | FEC_QUIRK_HAS_FRREG,
+	.quirks = FEC_QUIRK_MIB_CLEAR | FEC_QUIRK_HAS_FRREG |
+		  FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_imx28_info = {
 	.quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME |
 		  FEC_QUIRK_SINGLE_MDIO | FEC_QUIRK_HAS_RACC |
 		  FEC_QUIRK_HAS_FRREG | FEC_QUIRK_CLEAR_SETUP_MII |
-		  FEC_QUIRK_NO_HARD_RESET,
+		  FEC_QUIRK_NO_HARD_RESET | FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_imx6q_info = {
@@ -119,11 +120,12 @@ static const struct fec_devinfo fec_imx6q_info = {
 		  FEC_QUIRK_HAS_BUFDESC_EX | FEC_QUIRK_HAS_CSUM |
 		  FEC_QUIRK_HAS_VLAN | FEC_QUIRK_ERR006358 |
 		  FEC_QUIRK_HAS_RACC | FEC_QUIRK_CLEAR_SETUP_MII |
-		  FEC_QUIRK_HAS_PMQOS,
+		  FEC_QUIRK_HAS_PMQOS | FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_mvf600_info = {
-	.quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_RACC,
+	.quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_RACC |
+		  FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_imx6x_info = {
@@ -132,7 +134,8 @@ static const struct fec_devinfo fec_imx6x_info = {
 		  FEC_QUIRK_HAS_VLAN | FEC_QUIRK_HAS_AVB |
 		  FEC_QUIRK_ERR007885 | FEC_QUIRK_BUG_CAPTURE |
 		  FEC_QUIRK_HAS_RACC | FEC_QUIRK_HAS_COALESCE |
-		  FEC_QUIRK_CLEAR_SETUP_MII | FEC_QUIRK_HAS_MULTI_QUEUES,
+		  FEC_QUIRK_CLEAR_SETUP_MII | FEC_QUIRK_HAS_MULTI_QUEUES |
+		  FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_imx6ul_info = {
@@ -140,7 +143,8 @@ static const struct fec_devinfo fec_imx6ul_info = {
 		  FEC_QUIRK_HAS_BUFDESC_EX | FEC_QUIRK_HAS_CSUM |
 		  FEC_QUIRK_HAS_VLAN | FEC_QUIRK_ERR007885 |
 		  FEC_QUIRK_BUG_CAPTURE | FEC_QUIRK_HAS_RACC |
-		  FEC_QUIRK_HAS_COALESCE | FEC_QUIRK_CLEAR_SETUP_MII,
+		  FEC_QUIRK_HAS_COALESCE | FEC_QUIRK_CLEAR_SETUP_MII |
+		  FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_imx8mq_info = {
@@ -150,7 +154,8 @@ static const struct fec_devinfo fec_imx8mq_info = {
 		  FEC_QUIRK_ERR007885 | FEC_QUIRK_BUG_CAPTURE |
 		  FEC_QUIRK_HAS_RACC | FEC_QUIRK_HAS_COALESCE |
 		  FEC_QUIRK_CLEAR_SETUP_MII | FEC_QUIRK_HAS_MULTI_QUEUES |
-		  FEC_QUIRK_HAS_EEE | FEC_QUIRK_WAKEUP_FROM_INT2,
+		  FEC_QUIRK_HAS_EEE | FEC_QUIRK_WAKEUP_FROM_INT2 |
+		  FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_imx8qm_info = {
@@ -160,14 +165,15 @@ static const struct fec_devinfo fec_imx8qm_info = {
 		  FEC_QUIRK_ERR007885 | FEC_QUIRK_BUG_CAPTURE |
 		  FEC_QUIRK_HAS_RACC | FEC_QUIRK_HAS_COALESCE |
 		  FEC_QUIRK_CLEAR_SETUP_MII | FEC_QUIRK_HAS_MULTI_QUEUES |
-		  FEC_QUIRK_DELAYED_CLKS_SUPPORT,
+		  FEC_QUIRK_DELAYED_CLKS_SUPPORT | FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static const struct fec_devinfo fec_s32v234_info = {
 	.quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_GBIT |
 		  FEC_QUIRK_HAS_BUFDESC_EX | FEC_QUIRK_HAS_CSUM |
 		  FEC_QUIRK_HAS_VLAN | FEC_QUIRK_HAS_AVB |
-		  FEC_QUIRK_ERR007885 | FEC_QUIRK_BUG_CAPTURE,
+		  FEC_QUIRK_ERR007885 | FEC_QUIRK_BUG_CAPTURE |
+		  FEC_QUIRK_HAS_MDIO_C45,
 };
 
 static struct platform_device_id fec_devtype[] = {
@@ -2434,8 +2440,10 @@ static int fec_enet_mii_init(struct platform_device *pdev)
 	fep->mii_bus->name = "fec_enet_mii_bus";
 	fep->mii_bus->read = fec_enet_mdio_read_c22;
 	fep->mii_bus->write = fec_enet_mdio_write_c22;
-	fep->mii_bus->read_c45 = fec_enet_mdio_read_c45;
-	fep->mii_bus->write_c45 = fec_enet_mdio_write_c45;
+	if (fep->quirks & FEC_QUIRK_HAS_MDIO_C45) {
+		fep->mii_bus->read_c45 = fec_enet_mdio_read_c45;
+		fep->mii_bus->write_c45 = fec_enet_mdio_write_c45;
+	}
 	snprintf(fep->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x",
 		pdev->name, fep->dev_id + 1);
 	fep->mii_bus->priv = fep;