[coreboot] No external PCIe GPU possible/working on Gigabyte g41m-es2l

[Arthur Heymans]

Stefan Reinauer <stefan.reinauer at coreboot.org> writes:

> * i1w5d7gf38keg at tutanota.com <i1w5d7gf38keg at tutanota.com> [170226 21:59]:
>> Hardware: Gigabyte g41m-es2l, latest coreboot git, latest seabios git, two
>> nvidia gpu cards tested
>> 
>> I tried to use some external GPU on a g41m-es2l to get some digial screen
>> output. It does not seem to work. When having build coreboot with native
>> vga-init for the internal intel gpu, i never get a output from the nvidia card.
>> When i connect the analog VGA cable to the internal intel gpu and boot up i can
>> see many nouveau (memory-space?) errors. Both GPUs (nvidia and intel) are then
>> enabled at once. Kernel 4.10 cant boot.
>> 
>> I tried removing the native vga-init. The only change is then that the Intel
>> GPU works only when the kernel have load. Nvidia card deliver still same
>> errors.
>> 
>> With OEM-bios the intel card gets disabled and a PCIe GPU works fine.
>
> Please provide coreboot boot logs.
>
> Stefan

Actually https://review.coreboot.org/#/c/18504/
https://review.coreboot.org/#/c/18511/ (not sure if needed) and 
https://review.coreboot.org/#/c/18513/ (works but might be improved)
fix this issue.

-- 
Arthur Heymans