[PATCH 3/3] powerpc: replace vga_fixup() with generic code

[Daniel Axtens]

Michael Ellerman <mpe at ellerman.id.au> writes:

> Daniel Axtens <dja at axtens.net> writes:
>
>> Currently, we do a PCI fixup to mark a default card so that Xorg
>> autoconfiguration works.
>>
>> There is a new generic method to do this sort of vga fixup, and
>> it occurs by default.
>>
>> Drop our old method.
>>
>> This method is different:
>>  - it will only mark a card as default if a driver is bound
>>  - the marking will happen at late_initcall time, or even later
>>    if a card is enabled later on (via an ENABLE hook). Currently
>>    things are enabled in a FINAL hook.
>>
>> This *does* change behaviour under some circumstances.
>>
>> For example, pseries_le_defconfig doesn't have DRM drivers for
>> many of the qemu GPU models, including the 'standard' vga.
>
> Should we enable them/it?

Hard to say.

The 'standard' vga module (bochs_drm) was blacklisted by Ubuntu -
apparently at IBM's request [0] - some years back. Even if you
un-blacklist it, I had trouble with getting it and the openfirmware
framebuffer driver to play nicely together. It may not be worth the
trouble for bochs_drm.

There's a better case for including some of the more modern drivers -
maybe QXL and virtio - but I wasn't able to test them: my particular
build of qemu/TCG refused to start with them and I didn't feel like
rebuilding/debugging qemu.

It would also be legitmate to say that you're focussing on headless use
with pseries_*defconfig and not include them: you need to bring in the
DRM core if you want these drivers.

HTH.

Regards,
Daniel

[0] https://bugs.launchpad.net/ubuntu/+source/kmod/+bug/1378648

>
> cheers