AFAIK it can. I believe some UEFI implementations don't have CSM.

p_l · 2024-07-15T12:05:35 1721045135

a Type 3 UEFI implementation has no CSM, Type 2 has CSM available, Type 1 enforces booting into CSM (what many "BIOS"es actually was in later days)

EvanAnderson · 2024-07-15T15:41:01 1721058061

Thanks for that. That sent me down an enjoyable rabbit hole. I got started with PCs back in the 80s and became fairly familiar with how boot worked back then. UEFI happened while I was paying attention to other things and I've never become as familiar with it as I should be. This was a good excuse to do some reading.

deaddodo · 2024-07-15T15:42:03 1721058123

Just for clarification's sake, the proper terminology is "UEFI class" not "type".

Otherwise, this is accurate.