net: axienet: document axistream-connected attribute

[linux-2.6-block.git] / Documentation / devicetree / bindings / net / xilinx_axienet.txt

XILINX AXI ETHERNET Device Tree Bindings
--------------------------------------------------------

Also called  AXI 1G/2.5G Ethernet Subsystem, the xilinx axi ethernet IP core
provides connectivity to an external ethernet PHY supporting different
interfaces: MII, GMII, RGMII, SGMII, 1000BaseX. It also includes two
segments of memory for buffering TX and RX, as well as the capability of
offloading TX/RX checksum calculation off the processor.

Management configuration is done through the AXI interface, while payload is
sent and received through means of an AXI DMA controller. This driver
includes the DMA driver code, so this driver is incompatible with AXI DMA
driver.

For more details about mdio please refer phy.txt file in the same directory.

Required properties:
- compatible	: Must be one of "xlnx,axi-ethernet-1.00.a",
		  "xlnx,axi-ethernet-1.01.a", "xlnx,axi-ethernet-2.01.a"
- reg		: Address and length of the IO space, as well as the address
                  and length of the AXI DMA controller IO space, unless
                  axistream-connected is specified, in which case the reg
                  attribute of the node referenced by it is used.
- interrupts	: Should be a list of 2 or 3 interrupts: TX DMA, RX DMA,
		  and optionally Ethernet core. If axistream-connected is
		  specified, the TX/RX DMA interrupts should be on that node
		  instead, and only the Ethernet core interrupt is optionally
		  specified here.
- phy-handle	: Should point to the external phy device.
		  See ethernet.txt file in the same directory.
- xlnx,rxmem	: Set to allocated memory buffer for Rx/Tx in the hardware

Optional properties:
- phy-mode	: See ethernet.txt
- xlnx,phy-type	: Deprecated, do not use, but still accepted in preference
		  to phy-mode.
- xlnx,txcsum	: 0 or empty for disabling TX checksum offload,
		  1 to enable partial TX checksum offload,
		  2 to enable full TX checksum offload
- xlnx,rxcsum	: Same values as xlnx,txcsum but for RX checksum offload
- clocks	: AXI bus clock for the device. Refer to common clock bindings.
		  Used to calculate MDIO clock divisor. If not specified, it is
		  auto-detected from the CPU clock (but only on platforms where
		  this is possible). New device trees should specify this - the
		  auto detection is only for backward compatibility.
- axistream-connected: Reference to another node which contains the resources
		       for the AXI DMA controller used by this device.
		       If this is specified, the DMA-related resources from that
		       device (DMA registers and DMA TX/RX interrupts) rather
		       than this one will be used.
 - mdio		: Child node for MDIO bus. Must be defined if PHY access is
		  required through the core's MDIO interface (i.e. always,
		  unless the PHY is accessed through a different bus).

Example:
	axi_ethernet_eth: ethernet@40c00000 {
		compatible = "xlnx,axi-ethernet-1.00.a";
		device_type = "network";
		interrupt-parent = <&microblaze_0_axi_intc>;
		interrupts = <2 0 1>;
		clocks = <&axi_clk>;
		phy-mode = "mii";
		reg = <0x40c00000 0x40000 0x50c00000 0x40000>;
		xlnx,rxcsum = <0x2>;
		xlnx,rxmem = <0x800>;
		xlnx,txcsum = <0x2>;
		phy-handle = <&phy0>;
		axi_ethernetlite_0_mdio: mdio {
			#address-cells = <1>;
			#size-cells = <0>;
			phy0: phy@0 {
				device_type = "ethernet-phy";
				reg = <1>;
			};
		};
	};