On 31.03.2022 11:45, Jan Beulich wrote:
> When booting directly from EFI, obtaining this information from EFI is
> the only possible way. And even when booting with a boot loader
> interposed, it's more clean not to use legacy BIOS calls for this
> purpose. (The downside being that there are no "capabilities" that we
> can retrieve the EFI way.)
>
> To achieve this we need to propagate the handle used to obtain the
> EFI_GRAPHICS_OUTPUT_PROTOCOL instance for further obtaining an
> EFI_EDID_*_PROTOCOL instance, which has been part of the spec since 2.5.
>
> Signed-off-by: Jan Beulich <jbeul...@suse.com>
> ---
> Setting boot_edid_caps to zero isn't desirable, but arbitrarily setting
> one or both of the two low bits also doesn't seem appropriate.
>
> GrUB also checks an "agp-internal-edid" variable. As I haven't been able
> to find any related documentation, and as GrUB being happy about the
> variable being any size (rather than at least / precisely 128 bytes),
> I didn't follow that route.
> ---
> v3: Re-base.
> v2: New.
>
> --- a/xen/arch/arm/efi/efi-boot.h
> +++ b/xen/arch/arm/efi/efi-boot.h
> @@ -464,6 +464,10 @@ static void __init efi_arch_edd(void)
> {
> }
>
> +static void __init efi_arch_edid(EFI_HANDLE gop_handle)
> +{
> +}
> +
> static void __init efi_arch_memory_setup(void)
> {
> }
May I ask for an Arm side ack here, please?
Thanks, Jan
