[XS] Change in coreboot[main]: mb/asus/p8z77-m: Ensure RAM stays powered in ACPI S3 suspend

[Keith Hui (Code Review)]

Attention is currently required from: Kevin Keijzer, Paul Menzel.

Keith Hui has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78205?usp=email )

Change subject: mb/asus/p8z77-m: Ensure RAM stays powered in ACPI S3 suspend
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Patch Set 4:

(5 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/78205/comment/27b461dd_54cac256 :
PS2, Line 7: Fix ACPI S3 suspend
           :
> When 3VSBSW# is disabled, the RAM loses power in S3 suspend, so S3 resume fails. […]

Done

https://review.coreboot.org/c/coreboot/+/78205/comment/4ef014a3_7247451b :
PS2, Line 9: Enable 3VSBSW# in NCT6779D super I/O like other variants in the
           : family. Without it S3 suspend totally fails.
> It would be nice to factor in the root cause: S3 resume fails because the RAM was not powered during […]

Done

https://review.coreboot.org/c/coreboot/+/78205/comment/9ca1b5a7_d6330411 :
PS2, Line 10: S3 suspend totally fails
> nit: Strictly speaking, it is S3 *resume* that totally fails. […]

Acknowledged

Patchset:

PS2:
> @Paul, @Angel, I am holding off resolving the commit message comments because this patch is again no […]

...

Patchset:

PS4: 
For the record, this fix works for @Kevin, but didn't work for me at this moment. Seeing that my OS also couldn't power off by software, I may have other bigger problems.