Documentation: add Device tree bindings for Hisilicon hip04 ethernet

This patch adds the Device Tree bindings for the Hisilicon hip04
Ethernet controller, including 100M / 1000M controller.
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/hisilicon-hip04-net.txt

+Hisilicon hip04 Ethernet Controller
+
+* Ethernet controller node
+
+Required properties:
+- compatible: should be "hisilicon,hip04-mac".
+- reg: address and length of the register set for the device.
+- interrupts: interrupt for the device.
+- port-handle: <phandle port channel>
+	phandle, specifies a reference to the syscon ppe node
+	port, port number connected to the controller
+	channel, recv channel start from channel * number (RX_DESC_NUM)
+- phy-mode: see ethernet.txt [1].
+
+Optional properties:
+- phy-handle: see ethernet.txt [1].
+
+[1] Documentation/devicetree/bindings/net/ethernet.txt
+
+
+* Ethernet ppe node:
+Control rx & tx fifos of all ethernet controllers.
+Have 2048 recv channels shared by all ethernet controllers, only if no overlap.
+Each controller's recv channel start from channel * number (RX_DESC_NUM).
+
+Required properties:
+- compatible: "hisilicon,hip04-ppe", "syscon".
+- reg: address and length of the register set for the device.
+
+
+* MDIO bus node:
+
+Required properties:
+
+- compatible: should be "hisilicon,hip04-mdio".
+- Inherits from MDIO bus node binding [2]
+[2] Documentation/devicetree/bindings/net/phy.txt
+
+Example:
+	mdio {
+		compatible = "hisilicon,hip04-mdio";
+		reg = <0x28f1000 0x1000>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		phy0: ethernet-phy@0 {
+			compatible = "ethernet-phy-ieee802.3-c22";
+			reg = <0>;
+			marvell,reg-init = <18 0x14 0 0x8001>;
+		};
+
+		phy1: ethernet-phy@1 {
+			compatible = "ethernet-phy-ieee802.3-c22";
+			reg = <1>;
+			marvell,reg-init = <18 0x14 0 0x8001>;
+		};
+	};
+
+	ppe: ppe@28c0000 {
+		compatible = "hisilicon,hip04-ppe", "syscon";
+		reg = <0x28c0000 0x10000>;
+	};
+
+	fe: ethernet@28b0000 {
+		compatible = "hisilicon,hip04-mac";
+		reg = <0x28b0000 0x10000>;
+		interrupts = <0 413 4>;
+		phy-mode = "mii";
+		port-handle = <&ppe 31 0>;
+	};
+
+	ge0: ethernet@2800000 {
+		compatible = "hisilicon,hip04-mac";
+		reg = <0x2800000 0x10000>;
+		interrupts = <0 402 4>;
+		phy-mode = "sgmii";
+		port-handle = <&ppe 0 1>;
+		phy-handle = <&phy0>;
+	};
+
+	ge8: ethernet@2880000 {
+		compatible = "hisilicon,hip04-mac";
+		reg = <0x2880000 0x10000>;
+		interrupts = <0 410 4>;
+		phy-mode = "sgmii";
+		port-handle = <&ppe 8 2>;
+		phy-handle = <&phy1>;
+	};