It seems that some of the graphics device IDs for intel Comet Lake CPUs are incorrect. According to the supported GPU list [1], fixed them in https://review.coreboot.org/c/coreboot/+/83708. If you support a motherboard with -S or -H processors, then please take a look at this patch. And it would be great if someone from Intel checked out these changes.
Thx
[1] https://web.archive.org/web/20240731152818/https://dgpu-docs.intel.com/devic...
// Regards, // Max