Add support for changing Ethernet speeds

rtl837x_phy.h

@@ -1,8 +1,14 @@
 #ifndef _RTL837X_PHY_H_
 #define _RTL837X_PHY_H_
 
+#define PHY_SPEED_AUTO	0x1
+#define PHY_SPEED_1G	0x2
+#define PHY_SPEED_2G5	0x3
+#define PHY_OFF		0xff
+
 void rtl8224_phy_enable(void) __banked;
 void phy_config(uint8_t phy) __banked;
 void phy_config_8224(void) __banked;
+void phy_set_mode(uint8_t port, uint8_t speed, uint8_t flow_control, uint8_t duplex) __banked;
 
 #endif