diff options
Diffstat (limited to 'Documentation/devicetree/bindings/arm/xen.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/arm/xen.txt | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/arm/xen.txt b/Documentation/devicetree/bindings/arm/xen.txt new file mode 100644 index 0000000000..f925290d46 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/xen.txt @@ -0,0 +1,62 @@ +* 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. |