This patch set adds ACPI support for Xen Dom0 on ARM64. The relevant Xen
ACPI on ARM64 design document could be found from [1].
This patch set adds a new FDT node "uefi" under /hypervisor to pass UEFI
information. Introduce a bus notifier of AMBA and Platform bus to map
the new added device's MMIO space. Make Xen domain use
xlated_setup_gnttab_pages to setup grant table and a new hypercall to
get event-channel irq.
Regarding the initialization flow of Linux kernel, it needs to move
xen_early_init() before efi_init(). Then xen_early_init() will check
whether it runs on Xen through the /hypervisor node and efi_init() will
call a new function fdt_find_xen_uefi_params(), to parse those
xen,uefi-* parameters just like the existing efi_get_fdt_params().
And in arm64_enable_runtime_services() it will check whether it runs on
Xen and call another new function xen_efi_runtime_setup() to setup
runtime service instead of efi_native_runtime_setup(). The
xen_efi_runtime_setup() will assign the runtime function pointers with
the functions of driver/xen/efi.c.
And since we pass a /hypervisor node and a /chosen node to Dom0, it
needs to check whether the DTS only contains a /hypervisor node and a
/chosen node in acpi_boot_table_init().
Patches are tested on FVP base model. They can be fetched from[2].