[coreboot-gerrit] Change in coreboot[master]: apple/macbook21: configure the clockgen and add C3 CPU state

[Paul Menzel (Code Review)]

Attention is currently required from: Ferass EL HAFIDI, Arthur Heymans, Evgeny Zinoviev, Felix Held.
Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63587 )

Change subject: apple/macbook21: configure the clockgen and add C3 CPU state
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Patch Set 6:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/63587/comment/7a8f55c1_d9f8e412 
PS6, Line 11: 
Please extend the commit message, describing why the overridetree is needed for example, and which models have what clockgen, and so on.

File src/mainboard/apple/macbook21/cstates.c:

https://review.coreboot.org/c/coreboot/+/63587/comment/ec12b9db_fc463a5b 
PS4, Line 34: 		.latency = 17,
> That latency value works perfectly fine. […]

Only because you do not experience any problems with your use cases, this does not have to be the correct value, does it?

File src/mainboard/apple/macbook21/cstates.c:

https://review.coreboot.org/c/coreboot/+/63587/comment/570d484b_709275de 
PS6, Line 32: 	#if !CONFIG(BOARD_APPLE_IMAC52)
Preprocessor statement are not indented to my knowledge.