Hisilicon RoCE DT description

Hisilicon RoCE engine is a part of network subsystem.
It works depending on other part of network wubsytem, such as, gmac and
dsa fabric.

Additional properties are described here:

Required properties:
- compatible: Should contain "hisilicon,hns-roce-v1".
- reg: Physical base address of the RoCE driver and
length of memory mapped region.
- eth-handle: phandle, specifies a reference to a node
representing a ethernet device.
- dsaf-handle: phandle, specifies a reference to a node
representing a dsaf device.
- node_guid: a number that uniquely identifies a device or component
- #address-cells: must be 2
- #size-cells: must be 2
Optional properties:
- dma-coherent: Present if DMA operations are coherent.
- interrupts: should contain 32 completion event irq,1 async event irq
and 1 event overflow irq.
- interrupt-names:should be one of 34 irqs for roce device
  - hns-roce-comp-0 ~ hns-roce-comp-31: 32 complete event irq
  - hns-roce-async: 1 async event irq
  - hns-roce-common: named common exception warning irq
Example:
	infiniband@c4000000 {
			compatible = "hisilicon,hns-roce-v1";
			reg = <0x0 0xc4000000 0x0 0x100000>;
			dma-coherent;
			eth-handle = <&eth2 &eth3 &eth4 &eth5 &eth6 &eth7>;
			dsaf-handle = <&soc0_dsa>;
			node-guid = [00 9A CD 00 00 01 02 03];
			#address-cells = <2>;
			#size-cells = <2>;
			interrupt-parent = <&mbigen_dsa>;
			interrupts = <722 1>,
					<723 1>,
					<724 1>,
					<725 1>,
					<726 1>,
					<727 1>,
					<728 1>,
					<729 1>,
					<730 1>,
					<731 1>,
					<732 1>,
					<733 1>,
					<734 1>,
					<735 1>,
					<736 1>,
					<737 1>,
					<738 1>,
					<739 1>,
					<740 1>,
					<741 1>,
					<742 1>,
					<743 1>,
					<744 1>,
					<745 1>,
					<746 1>,
					<747 1>,
					<748 1>,
					<749 1>,
					<750 1>,
					<751 1>,
					<752 1>,
					<753 1>,
					<785 1>,
					<754 4>;

			interrupt-names = "hns-roce-comp-0",
					"hns-roce-comp-1",
					"hns-roce-comp-2",
					"hns-roce-comp-3",
					"hns-roce-comp-4",
					"hns-roce-comp-5",
					"hns-roce-comp-6",
					"hns-roce-comp-7",
					"hns-roce-comp-8",
					"hns-roce-comp-9",
					"hns-roce-comp-10",
					"hns-roce-comp-11",
					"hns-roce-comp-12",
					"hns-roce-comp-13",
					"hns-roce-comp-14",
					"hns-roce-comp-15",
					"hns-roce-comp-16",
					"hns-roce-comp-17",
					"hns-roce-comp-18",
					"hns-roce-comp-19",
					"hns-roce-comp-20",
					"hns-roce-comp-21",
					"hns-roce-comp-22",
					"hns-roce-comp-23",
					"hns-roce-comp-24",
					"hns-roce-comp-25",
					"hns-roce-comp-26",
					"hns-roce-comp-27",
					"hns-roce-comp-28",
					"hns-roce-comp-29",
					"hns-roce-comp-30",
					"hns-roce-comp-31",
					"hns-roce-async",
					"hns-roce-common";
		};
