Initialize graphics on iMac efi the same way as in legacy mode

[tenzap]

I've installed Linux debian on iMac 9.1 in efi mode but I sometimes face display issues. I slightly changed the boot config to boot it in legacy mode, and the result is better by some aspects.

I understood that the graphics card is initialized differently in legacy mode that in efi mode.

I there a way, with clover, to boot Debian in EFI mode and having the graphics initialization done as in the legacy mode?

I read the wiki and I can't figure out if this is a use case of clover.

Graphics hardware on this iMac is Nvidia based (Nvidia Tesla architecture).

I suppose this would also be of interest to those who try to boot windows on a Mac in efi mode instead of legacy. Most people seem to experience failures with windows/efi in relation to graphics.