Index: sys/dev/etherswitch/ip17x/ip175c.h
===================================================================
--- sys/dev/etherswitch/ip17x/ip175c.h
+++ sys/dev/etherswitch/ip17x/ip175c.h
@@ -35,6 +35,9 @@
 #define	IP175C_MODE_REG			31
 #define	IP175C_RESET_PHY		30
 #define	IP175C_RESET_REG		0
+#define	IP175C_MII_PHY			31
+#define	IP175C_MII_CTL_REG		5
+#define	IP175C_MII_MII1_RMII_EN		8
 
 #define	IP175C_LAST_VLAN		15
 
Index: sys/dev/etherswitch/ip17x/ip175c.c
===================================================================
--- sys/dev/etherswitch/ip17x/ip175c.c
+++ sys/dev/etherswitch/ip17x/ip175c.c
@@ -234,6 +234,13 @@
 void
 ip175c_attach(struct ip17x_softc *sc)
 {
+	uint32_t data;
+
+	data = ip17x_readphy(sc->sc_dev, IP175C_MII_PHY, IP175C_MII_CTL_REG);
+	device_printf(sc->sc_dev, "MII: %x\n", data);
+	/* check mii1 interface if disabled then phy4 and mac4 hold on switch */
+	if((data & (1 << IP175C_MII_MII1_RMII_EN)) == 0)
+		sc->phymask |= 0x10;
 
 	sc->hal.ip17x_reset = ip175c_reset;
 	sc->hal.ip17x_hw_setup = ip175c_hw_setup;