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+* Xen hypervisor device tree bindings
+
+Xen ARM virtual platforms shall have a top-level "hypervisor" node with
+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 the regions in memory
+  where the special resources should be mapped to, using an HYPERVISOR_memory_op
+  hypercall.
+  Region 0 is reserved for mapping grant table, it must be always present.
+  The memory region is large enough to map the whole grant table (it is larger
+  or equal to gnttab_max_grant_frames()).
+  Regions 1...N are extended regions (unused address space) for mapping foreign
+  GFNs and grants, they might be absent if there is nothing to expose.
+
+- interrupts: the interrupt used by Xen to inject event notifications.
+  A GIC node is also required.
+
+To support UEFI on Xen ARM virtual platforms, Xen populates the FDT "uefi" node
+under /hypervisor with following parameters:
+
+________________________________________________________________________________
+Name                      | Size   | Description
+================================================================================
+xen,uefi-system-table     | 64-bit | Guest physical address of the UEFI System
+			  |	   | Table.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-start       | 64-bit | Guest physical address of the UEFI memory
+			  |	   | map.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-size        | 32-bit | Size in bytes of the UEFI memory map
+                          |        | pointed to in previous entry.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-desc-size   | 32-bit | Size in bytes of each entry in the UEFI
+                          |        | memory map.
+--------------------------------------------------------------------------------
+xen,uefi-mmap-desc-ver    | 32-bit | Version of the mmap descriptor format.
+--------------------------------------------------------------------------------
+
+Example (assuming #address-cells = <2> and #size-cells = <2>):
+
+hypervisor {
+	compatible = "xen,xen-4.3", "xen,xen";
+	reg = <0 0xb0000000 0 0x20000>;
+	interrupts = <1 15 0xf08>;
+	uefi {
+		xen,uefi-system-table = <0xXXXXXXXX>;
+		xen,uefi-mmap-start = <0xXXXXXXXX>;
+		xen,uefi-mmap-size = <0xXXXXXXXX>;
+		xen,uefi-mmap-desc-size = <0xXXXXXXXX>;
+		xen,uefi-mmap-desc-ver = <0xXXXXXXXX>;
+        };
+};
+
+The format and meaning of the "xen,uefi-*" parameters are similar to those in
+Documentation/arch/arm/uefi.rst, which are provided by the regular UEFI stub. However
+they differ because they are provided by the Xen hypervisor, together with a set
+of UEFI runtime services implemented via hypercalls, see
+http://xenbits.xen.org/docs/unstable/hypercall/x86_64/include,public,platform.h.html.