Re: [PATCH 4/7] arm: efi: add a generic efi machine.

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hi,

On 31.08.25 05:55, chalianis1@gmail.com wrote:
> From: Chali Anis <chalianis1@gmail.com>
> 
> add a generic arm64 machine that can select the CPU_V8 and the
> required efi payload minimal configs. this machine permits to have
> a clean arm64 efi payload, idealy we don't need the other machine
> that comes from multi arch since they execute code that is specific
> for the correspondig hardware. with this generic efi machine the
> barebox log shell is more clean. to get a pure clean efi payload
> you need to unselect all the other arch machines and keep only the
> EFI ARM64.
> 
> Signed-off-by: Chali Anis <chalianis1@gmail.com>
> ---
>  arch/arm/Kconfig | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index cce71b50eb04..0a098440ddde 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -254,6 +254,18 @@ config ARCH_ZYNQMP
>  	select GPIOLIB
>  	select HAS_MACB
>  
> +config EFI_ARM64

Thinking about it, this doesn't really fit into the existing model.
We have CONFIG_EFI_PAYLOAD, which when enabled gives _all_ images
an EFI stub.

I think it's better to just give CPU_V7 and CPU_V8 prompts.
Then they can be enabled for the barebones EFI-only use case alongside
CONFIG_EFI_PAYLOAD. CONFIG_EFI_PAYLOAD should have its depends on
COMPILE_TEST removed as last patch in your series then I think (or
before last if you add a dedicated efi_defconfig).

> +	bool "EFI on ARM64"

Generally, we should call it EFI payload to differentiate from
EFI loader (firmware)

> +	select CPU_V8
> +	select CPU_SUPPORTS_64BIT_KERNEL

Symbol doesn't exist on ARM.

> +	select HAVE_EFI_PAYLOAD

Already selected by CPU_64

> +	select EFI_PAYLOAD
> +	select BOOTM_FITIMAGE

select means it can't be deselected, which is not needed here.

> +    select CLOCKSOURCE_EFI
> +    select DRIVER_VIDEO_EFI_GOP

It's reasonable to disable GOP if the device is headless anyway.
You can give the DRIVER_VIDEO_EFI_GOP a default y though if you like,
because many (most?) users will likely want to use GOP.

Point is moot with above suggested change though.

> +	depends on 64BIT
> +	default y if ARCH_MULTIARCH

> +
>  source "arch/arm/cpu/Kconfig"
>  source "arch/arm/mach-at91/Kconfig"
>  source "arch/arm/mach-bcm283x/Kconfig"


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