| Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | * Xen hypervisor device tree bindings |
| 2 | |
| 3 | Xen ARM virtual platforms shall have a top-level "hypervisor" node with |
| 4 | the 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 the regions in memory |
| 11 | where the special resources should be mapped to, using an HYPERVISOR_memory_op |
| 12 | hypercall. |
| 13 | Region 0 is reserved for mapping grant table, it must be always present. |
| 14 | The memory region is large enough to map the whole grant table (it is larger |
| 15 | or equal to gnttab_max_grant_frames()). |
| 16 | Regions 1...N are extended regions (unused address space) for mapping foreign |
| 17 | GFNs and grants, they might be absent if there is nothing to expose. |
| 18 | |
| 19 | - interrupts: the interrupt used by Xen to inject event notifications. |
| 20 | A GIC node is also required. |
| 21 | |
| 22 | To support UEFI on Xen ARM virtual platforms, Xen populates the FDT "uefi" node |
| 23 | under /hypervisor with following parameters: |
| 24 | |
| 25 | ________________________________________________________________________________ |
| 26 | Name | Size | Description |
| 27 | ================================================================================ |
| 28 | xen,uefi-system-table | 64-bit | Guest physical address of the UEFI System |
| 29 | | | Table. |
| 30 | -------------------------------------------------------------------------------- |
| 31 | xen,uefi-mmap-start | 64-bit | Guest physical address of the UEFI memory |
| 32 | | | map. |
| 33 | -------------------------------------------------------------------------------- |
| 34 | xen,uefi-mmap-size | 32-bit | Size in bytes of the UEFI memory map |
| 35 | | | pointed to in previous entry. |
| 36 | -------------------------------------------------------------------------------- |
| 37 | xen,uefi-mmap-desc-size | 32-bit | Size in bytes of each entry in the UEFI |
| 38 | | | memory map. |
| 39 | -------------------------------------------------------------------------------- |
| 40 | xen,uefi-mmap-desc-ver | 32-bit | Version of the mmap descriptor format. |
| 41 | -------------------------------------------------------------------------------- |
| 42 | |
| 43 | Example (assuming #address-cells = <2> and #size-cells = <2>): |
| 44 | |
| 45 | hypervisor { |
| 46 | compatible = "xen,xen-4.3", "xen,xen"; |
| 47 | reg = <0 0xb0000000 0 0x20000>; |
| 48 | interrupts = <1 15 0xf08>; |
| 49 | uefi { |
| 50 | xen,uefi-system-table = <0xXXXXXXXX>; |
| 51 | xen,uefi-mmap-start = <0xXXXXXXXX>; |
| 52 | xen,uefi-mmap-size = <0xXXXXXXXX>; |
| 53 | xen,uefi-mmap-desc-size = <0xXXXXXXXX>; |
| 54 | xen,uefi-mmap-desc-ver = <0xXXXXXXXX>; |
| 55 | }; |
| 56 | }; |
| 57 | |
| 58 | The format and meaning of the "xen,uefi-*" parameters are similar to those in |
| 59 | Documentation/arch/arm/uefi.rst, which are provided by the regular UEFI stub. However |
| 60 | they differ because they are provided by the Xen hypervisor, together with a set |
| 61 | of UEFI runtime services implemented via hypercalls, see |
| 62 | http://xenbits.xen.org/docs/unstable/hypercall/x86_64/include,public,platform.h.html. |