docs: Xen ARM DT bindings

Add a doc to describe the Xen ARM device tree bindings

Changes in v4:

- "xen,xen" should be last as it is less specific;
- update reg property using 2 address-cells and 2 size-cells.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC: devicetree-discuss@lists.ozlabs.org
CC: David Vrabel <david.vrabel@citrix.com>
CC: Rob Herring <robherring2@gmail.com>
CC: Dave Martin <dave.martin@linaro.org>

diff --git a/Documentation/devicetree/bindings/arm/xen.txt b/Documentation/devicetree/bindings/arm/xen.txt
new file mode 100644 (file)
index 0000000..1f8f7d4
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/xen.txt
@@ -0,0 +1,22 @@
+* Xen hypervisor device tree bindings
+
+Xen ARM virtual platforms shall have the following properties:
+
+- compatible:
+       compatible = "xen,xen-<version>", "xen,xen";
+  where <version> is the version of the Xen ABI of the platform.
+
+- reg: specifies the base physical address and size of a region in
+  memory where the grant table should be mapped to, using an
+  HYPERVISOR_memory_op hypercall. 
+
+- interrupts: the interrupt used by Xen to inject event notifications.
+
+
+Example:
+
+hypervisor {
+       compatible = "xen,xen-4.3", "xen,xen";
+       reg = <0 0xb0000000 0 0x20000>;
+       interrupts = <1 15 0xf08>;
+};