Re: [PATCH 3/8] firmware: sysfb: Make CONFIG_SYSFB a user-selectable option

[Thomas Zimmermann <tzimmermann@suse.de>]

Hi

Am 02.04.26 um 15:08 schrieb Arnd Bergmann:
> On Thu, Apr 2, 2026, at 11:09, Thomas Zimmermann wrote:
>> Add a descriptive string and help text to CONFIG_SYSFB, so that users
>> can modify it. Flip all implicit selects in the Kconfig options into
>> dependencies. This avoids cyclic dependencies in the config.
>>
>> Enabling CONFIG_SYSFB makes the kernel provide a device for the firmware
>> framebuffer. As this can (slightly) affect system behavior, having a
>> user-facing option seems preferable. Some users might also want to set
>> every detail of their kernel config.
>>
>> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> I don't really like this part of the series and would prefer
> to keep CONFIG_SYSFB hidden as much as possible as an x86
> (and EFI) specific implementation detail, with the hope
> of eventually seperating out the x86 bits from the EFI ones.

You mean, you want to use the EFI-provided framebuffers without the 
intermediate step of going through sysfb_primary_display?

In that case, CONFIG_SYSFB would become an x86-internal thing, right?

>
> In general, I am always in favor of properly using Kconfig
> dependencies over 'select' statements, for the same reasons
> you describe, but I don't want the the x86 logic for
> the legacy VESA and VGA console handling to leak into more
> architectures than necessary.
>
> Do you think we could instead move the sysfb_init()
> function into the same two places that contain the
> sysfb_primary_display definition (arch/x86/kernel/setup.c,
> drivers/firmware/efi/efi-init.c) and simplify the efi version
> to take out the x86 bits? That would reduce the rest
> of sysfb-primary.c to the logic to unregister the device,
> and that could then be selected by both x86 and EFI.

No, I'm more than happy that sysfb finally consolidates all the 
init-framebuffer setup and detection that floated around in the kernel. 
I would not want it to be duplicated again.

For now, we could certainly keep CONFIG_SYSFB hidden and autoselected. 
Although I think this will require soem sort of solution at a later point.

Best regards
Thomas

>
>        Arnd

-- 
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Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
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