ARM: dts: iwg22d-sodimm: Add Ethernet AVB support

Define the iWave RainboW-G22D board dependent part of the Ethernet
AVB device node.

On some older versions of the platform (before R4.0) the phy address
may be 1 or 3. The address is fixed to 3 for R4.0 onwards (which
will be the first mainstream release), hence using 3 in the dts.
Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Signed-off-by: Chris Paterson <chris.paterson2@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7745-iwg22d-sodimm.dts

@@ -17,9 +17,11 @@ / {
 
 	aliases {
 		serial0 = &scif4;
+		ethernet0 = &avb;
 	};
 
 	chosen {
+		bootargs = "ignore_loglevel rw root=/dev/nfs ip=dhcp";
 		stdout-path = "serial0:115200n8";
 	};
 };
@@ -29,6 +31,11 @@ scif4_pins: scif4 {
 		groups = "scif4_data_b";
 		function = "scif4";
 	};
+
+	avb_pins: avb {
+		groups = "avb_mdio", "avb_gmii";
+		function = "avb";
+	};
 };
 
 &scif4 {
@@ -37,3 +44,22 @@ &scif4 {
 
 	status = "okay";
 };
+
+&avb {
+	pinctrl-0 = <&avb_pins>;
+	pinctrl-names = "default";
+
+	phy-handle = <&phy3>;
+	phy-mode = "gmii";
+	renesas,no-ether-link;
+	status = "okay";
+
+	phy3: ethernet-phy@3 {
+	/*
+	 * On some older versions of the platform (before R4.0) the phy address
+	 * may be 1 or 3. The address is fixed to 3 for R4.0 onwards.
+	 */
+		reg = <3>;
+		micrel,led-mode = <1>;
+	};
+};