[S] Change in coreboot[main]: cpu/x86: Add 1GiB pages for memory access up to 512GiB

[Arthur Heymans (Code Review)]

Attention is currently required from: Ashish Kumar Mishra, Jérémy Compostella, Paul Menzel, Subrata Banik, Wonkyu Kim.

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/80088?usp=email )

Change subject: cpu/x86: Add 1GiB pages for memory access up to 512GiB
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Patch Set 5: Code-Review-1

(1 comment)

Patchset:

PS5: 
This assumes a physical address space of 41 bits which is not always the case on all hardware supporting 4G tables. Also you might need to trampoline into long mode with limited page tables (4G first) before setting up larger ones. At least I had some troubles on real hardware with this kind of setup.