设备树 macb

* Cadence MACB/GEM Ethernet controller

Required properties:
- compatible: Should be "cdns,[<chip>-]{macb|gem}"
  Use "cdns,at91rm9200-emac" Atmel at91rm9200 SoC.
  Use "cdns,at91sam9260-macb" for Atmel at91sam9 SoCs or the 10/100Mbit IP
  available on sama5d3 SoCs.
  Use "cdns,np4-macb" for NP4 SoC devices.
  Use "cdns,at32ap7000-macb" for other 10/100 usage or use the generic form: "cdns,macb".
  Use "cdns,pc302-gem" for Picochip picoXcell pc302 and later devices based on
  the Cadence GEM, or the generic form: "cdns,gem".
  Use "atmel,sama5d2-gem" for the GEM IP (10/100) available on Atmel sama5d2 SoCs.
  Use "atmel,sama5d3-macb" for the 10/100Mbit IP available on Atmel sama5d3 SoCs.
  Use "atmel,sama5d3-gem" for the Gigabit IP available on Atmel sama5d3 SoCs.
  Use "atmel,sama5d4-gem" for the GEM IP (10/100) available on Atmel sama5d4 SoCs.
  Use "cdns,zynq-gem" Xilinx Zynq-7xxx SoC.
  Use "cdns,zynqmp-gem" for Zynq Ultrascale+ MPSoC.
  Or the generic form: "cdns,emac".
- reg: Address and length of the register set for the device
- interrupts: Should contain macb interrupt
- phy-mode: See ethernet.txt file in the same directory.
- clock-names: Tuple listing input clock names.
	Required elements: 'pclk', 'hclk'
	Optional elements: 'tx_clk'
	Optional elements: 'rx_clk' applies to cdns,zynqmp-gem
	Optional elements: 'tsu_clk'
- clocks: Phandles to input clocks.

Optional properties for PHY child node:
- reset-gpios : Should specify the gpio for phy reset
- magic-packet : If present, indicates that the hardware supports waking
  up via magic packet.
- phy-handle : see ethernet.txt file in the same directory

Optional properties:
- tsu-clk: Time stamp unit clock frequency used.
- rx-watermark: Set watermark value for pbuf_rxcutthru reg and enable
  rx partial store and forward, only when compatible = "cdns,zynqmp-gem".
  Value should be less than 0xFFF.

Examples:

	macb0: [email protected] {
		compatible = "cdns,at32ap7000-macb";
		reg = <0xfffc4000 0x4000>;
		interrupts = <21>;
		rx-watermark = /bits/ 16 <0x44>;
		phy-mode = "rmii";
		local-mac-address = [3a 0e 03 04 05 06];
		clock-names = "pclk", "hclk", "tx_clk";
		clocks = <&clkc 30>, <&clkc 30>, <&clkc 13>;
		[email protected] {
			reg = <0x1>;
			reset-gpios = <&pioE 6 1>;
		};
	};

以下内容是谷歌翻译：

* Cadence MACB / GEM以太网控制器

必需的属性：
-兼容：应为“ cdns，[<chip>-] {macb | gem}”
  使用“ cdns，at91rm9200-emac” Atmel at91rm9200 SoC。
  对Atmel at91sam9 SoC或10 / 100Mbit IP使用“ cdns，at91sam9260-macb”
  在sama5d3 SoC上可用。
  对于NP4 SoC设备使用“ cdns，np4-macb”。
  将“ cdns，at32ap7000-macb”用于其他10/100用法，或使用通用形式：“ cdns，macb”。
  对于基于Picochip picoXcell pc302和更高版本的设备，请使用“ cdns，pc302-gem”
  Cadence GEM或通用形式：“ cdns，gem”。
  对于Atmel sama5d2 SoC上可用的GEM IP（10/100），请使用“ atmel，sama5d2-gem”。
  对于Atmel sama5d3 SoC上可用的10 / 100Mbit IP，请使用“ atmel，sama5d3-macb”。
  对于Atmel sama5d3 SoC上可用的千兆位IP，请使用“ atmel，sama5d3-gem”。
  对于Atmel sama5d4 SoC上可用的GEM IP（10/100），请使用“ atmel，sama5d4-gem”。
  使用“ cdns，zynq-gem” Xilinx Zynq-7xxx SoC。
  对于Zynq Ultrascale + MPSoC使用“ cdns，zynqmp-gem”。
  或通用形式：“ cdns，emac”。
-reg：设备设置的寄存器的地址和长度
-中断：应包含macb中断
-phy模式：请参阅同一目录中的ethernet.txt文件。
-clock-names：元组列出输入时钟名称。
必填元素：“ pclk”，“ hclk”
可选元素：“ tx_clk”
可选元素：“ rx_clk”适用于cdns，zynqmp-gem
可选元素：“ tsu_clk”
-时钟：用于输入时钟的句柄。

PHY子节点的可选属性：
-reset-gpios：应为phy重置指定gpio
-magic-packet：如果存在，则表示硬件支持唤醒
  通过魔术包。
-phy-handle：请参阅同一目录中的ethernet.txt文件

可选属性：
-tsu-clk：使用的时间戳单位时钟频率。
-rx-watermark：设置pbuf_rxcutthru reg的水印值并启用
  仅当compatible =“ cdns，zynqmp-gem”时，rx部分存储和转发。
  值应小于0xFFF。

例子：

macb0：ethernet @ fffc4000 {
兼容=“ cdns，at32ap7000-macb”;
reg = <0xfffc4000 0x4000>;
中断= <21>;
rx-watermark = / bits / 16 <0x44>;
phy-mode =“ rmii”;
local-mac-address = [3a 0e 03 04 05 06];
时钟名称=“ pclk”，“ hclk”，“ tx_clk”；
时钟= <＆clkc 30>，<＆clkc 30>，<＆clkc 13>;
ethernet-phy @ 1 {
reg = <0x1>;
reset-gpios = <＆pioE 6 1>;
};
};