[coreboot] Intel G41 - Asrock G41M-GS: no coreboot screen output from Intel GPU on VGA

[Nico Huber]

On 01.09.2018 23:13, h42 at memeware.net wrote:
> Cherry picking did not worked for me. I cloned coreboot today on an new
> linux installation.

The submodule pointer didn't change since June. Something must be wrong
with your checkout. To be sure I just picked said commit on 718c79b:

  $ git log -2 --oneline
  e9a4ba2 (HEAD) gma pipe_setup: Work around a PFIT_CONTROL quirk on G45
  718c79b g45/hw-gfx-gma-gmch-hdmi.adb: Use GMCH_HDMI_MODE_SELECT_DVI

> So i did additional:
> $ cd 3rdparty/libgfxinit/
> $ git checkout master
> $ cd -
> $ git add 3rdparty/libgfxinit/
> 
> Then i build the buildroot and the coreboot image.
> I think i should have the patch (and some other things that was merged
> in between) now inside the image. But i still dont have any seabios
> output on the screen. I am using seabios master.

Sorry to hear that. Might still be some incompatibility with your
hardware. If it works with the linear framebuffer option that might
hint again towards the scaler. OTOH, libgfxinit master is not tested
at all against coreboot atm.

> 
> Then i tried out linear (high resolution) framebuffer.
> I got that when building:
> ...
>     CC         ramstage/drivers/intel/wifi/wifi.o
>     GCC        ramstage/drivers/intel/gma/hires_fb/gma.o
> gma.adb:78:59: expected type "Interfaces.Integer_16"
> gma.adb:78:59: found type "Interfaces.Integer_32"
> gma.adb:79:59: expected type "Interfaces.Integer_16"
> gma.adb:79:59: found type "Interfaces.Integer_32"
> Makefile:338: recipe for target
> 'build/ramstage/drivers/intel/gma/hires_fb/gma.o' failed
> make: *** [build/ramstage/drivers/intel/gma/hires_fb/gma.o] Error 1

That's much expected because libgfxinit master is not compatible to
coreboot (the interface changed, so coreboot will need an update). The
linear framebuffer option should work with the unaltered submodule
pointer, however.

Nico