With libgfxinit, you don't need any VBIOS for the Intel GPU.
I first got a working display with the GOP driver, but I'll try libgfxinit again. Would there be a difference between the vendor's VBT and the one that I've been using with the FSP?
The Nvidia GPU might need a VBIOS, but I don't think you need to run it in coreboot, as the OS should be able to handle it.
`sudo lspci -vvv | grep "Expansion ROM"` is only giving me one for the integrated GPU, so I'm slightly confused (but it's mentioned here (https://coreboot.coreboot.narkive.com/zEkIcuSS/ultimate-vgabios-extraction-n...) that the Linux kernel method only worked for the integrated GPU, so perhaps this is expected. However, now I'm also concerned that the vendor firmware could be patching the ROM in memory). I've been including one for the dGPU anyway.
Thanks for your help.