xref: /freebsd/sys/contrib/device-tree/Bindings/arm/xen.txt (revision 18f21f0355481283ceef0ec10e99554f44c205c2)
1* Xen hypervisor device tree bindings
2
3Xen ARM virtual platforms shall have a top-level "hypervisor" node with
4the following properties:
5
6- compatible:
7	compatible = "xen,xen-<version>", "xen,xen";
8  where <version> is the version of the Xen ABI of the platform.
9
10- reg: specifies the base physical address and size of a region in
11  memory where the grant table should be mapped to, using an
12  HYPERVISOR_memory_op hypercall. The memory region is large enough to map
13  the whole grant table (it is larger or equal to gnttab_max_grant_frames()).
14  This property is unnecessary when booting Dom0 using ACPI.
15
16- interrupts: the interrupt used by Xen to inject event notifications.
17  A GIC node is also required.
18  This property is unnecessary when booting Dom0 using ACPI.
19
20To support UEFI on Xen ARM virtual platforms, Xen populates the FDT "uefi" node
21under /hypervisor with following parameters:
22
23________________________________________________________________________________
24Name                      | Size   | Description
25================================================================================
26xen,uefi-system-table     | 64-bit | Guest physical address of the UEFI System
27			  |	   | Table.
28--------------------------------------------------------------------------------
29xen,uefi-mmap-start       | 64-bit | Guest physical address of the UEFI memory
30			  |	   | map.
31--------------------------------------------------------------------------------
32xen,uefi-mmap-size        | 32-bit | Size in bytes of the UEFI memory map
33                          |        | pointed to in previous entry.
34--------------------------------------------------------------------------------
35xen,uefi-mmap-desc-size   | 32-bit | Size in bytes of each entry in the UEFI
36                          |        | memory map.
37--------------------------------------------------------------------------------
38xen,uefi-mmap-desc-ver    | 32-bit | Version of the mmap descriptor format.
39--------------------------------------------------------------------------------
40
41Example (assuming #address-cells = <2> and #size-cells = <2>):
42
43hypervisor {
44	compatible = "xen,xen-4.3", "xen,xen";
45	reg = <0 0xb0000000 0 0x20000>;
46	interrupts = <1 15 0xf08>;
47	uefi {
48		xen,uefi-system-table = <0xXXXXXXXX>;
49		xen,uefi-mmap-start = <0xXXXXXXXX>;
50		xen,uefi-mmap-size = <0xXXXXXXXX>;
51		xen,uefi-mmap-desc-size = <0xXXXXXXXX>;
52		xen,uefi-mmap-desc-ver = <0xXXXXXXXX>;
53        };
54};
55
56The format and meaning of the "xen,uefi-*" parameters are similar to those in
57Documentation/arm/uefi.rst, which are provided by the regular UEFI stub. However
58they differ because they are provided by the Xen hypervisor, together with a set
59of UEFI runtime services implemented via hypercalls, see
60http://xenbits.xen.org/docs/unstable/hypercall/x86_64/include,public,platform.h.html.
61