mikeb mikeb has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/31448 )
Change subject: src/device/pci: Add support for discrete VGA initialization and OpROM loading ......................................................................
Patch Set 1:
Patch Set 1:
The Kconfig option seems useless.
Which option, and why useless?
Patch Set 1:
Can't you simply write two VFCT acpi tables ? Looking at the code that be possible.
I tried doing that but my discrete GPU did not work because of initialization errors. And I don't know how to create a single working table for both of them, so I am not doing it yet.
Is it safe to load / run two option ROMs ? I'd only load the primary one.
If you will not load the OpROM for your discrete GPU, and it does not have its' own memory with a local copy of OpROM stored, then your discrete GPU will fail to initialize and will not be working. At least that's the case for laptop discrete AMD GPUs. But if you don't need a working discrete GPU (e.g. because you are not satisfied with its' performance), then you could include only your primary option ROM to CBFS.
This patch should be split into two parts: One for providing multiple VFCT tables, and one for option ROM loading.
I do not plan to change the VFCT part because of the reasons mentioned above and at commit message, but please let me know if I still need to separate it into a different patch.