[coreboot-gerrit] Change in coreboot[master]: mb/prodrive/hermes: Disable ACPI S3 and S4 with SPS

[Angel Pons (Code Review)]

Attention is currently required from: [e-mail], Guido Beyer @ Prodrive Technologies, Justin van Son, Patrick Rudolph, Christian Walter, Michael Niewöhner, Stef van Os.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54058 )

Change subject: mb/prodrive/hermes: Disable ACPI S3 and S4 with SPS
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Patch Set 1:

(1 comment)

Patchset:

PS1:
> x11 boards could use that too, then

I'd prefer to go with the current approach for now, and adjust things later on if need be.

Does S3 resume work on the X11 boards with ME instead of SPS? Something you could check is whether the RAM can ever stay powered on in S3, where only the +5VSB rail remains powered on.

If S3 support is impossible on the X11 boards, they should not select HAVE_ACPI_RESUME. S4 might still work, as it shouldn't require special hardware support.

Otherwise, if S3 works with ME firmware, then the exact procedure to follow should be documented, and we would need to have a similar Kconfig option on the X11 boards.

Ideally, coreboot would detect the ME/SPS firmware SKU and report supported sleep states accordingly. However, this involves more work.