[S] Change in coreboot[main]: cpu/intel/model_206ax: Allow turbo boost ratio limit configuration

[Anastasios Koutian (Code Review)]

Attention is currently required from: Angel Pons.

Anastasios Koutian has posted comments on this change by Anastasios Koutian. ( https://review.coreboot.org/c/coreboot/+/83271?usp=email )

Change subject: cpu/intel/model_206ax: Allow turbo boost ratio limit configuration
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Patch Set 2:

(2 comments)

Patchset:

PS2:
> Also see CB:42547 which admittedly I haven't really taken care of.

Thank you, I saw your change but assumed it to be stale so I decided to start fresh.

Commit Message:

https://review.coreboot.org/c/coreboot/+/83271/comment/3b610378_4431a537?usp... :
PS2, Line 9: Tested on ThinkPad T420 with the i7-3940XM.
> Hmmm, I don't see any changes to the T420. […]

This branch is intended to enable setting the values in devicetree.cb.
I haven't included the changes to T420 devicetree.cb in this branch, since I wanted to keep it single-topic, but I have tested it locally and it works.

I have a separate branch with changes to T420 devicetree.cb which use the vendor default values for TCC offset, PL1/PL2 and current limits. I intend to push this for review after this branch is merged.

That being said, I also like the idea of making these CMOS options. That way users don't need to recompile and flash in order to change power limits. Perhaps we can think about it.