[Solved] Keep Intel iGPU enabled on MacBook on Fedora 30?
Edit: Solved; build and guide here
I have a rMBP, an eGPU (Thunder2), and a RX 580. The eGPU seemingly works great (outputs to an external display, and performance is good).
I can't hot-plug the eGPU after boot (amdgpu kernel module fails to load), so it seems one way to work around this is to have the eGPU plugged in at boot. Doing this however disables the Intel iGPU.
I'd like to have the Intel iGPU enabled in order to use the internal display, and to be able to use DRI_PRIME to use the eGPU for acceleration as-needed.
If I read right, I can use GRUB to chain load apple_set_os.efi to let EFI keep the iGPU enabled? I tried this briefly, but it didn't work (likely I didn't set it up correctly). Does anyone have any modern-day instructions on how to do this correctly, preferably on recent distros like Fedora 30?