[M] Change in coreboot[master]: soc/intel/meteorlake: Skip setting D0I3 bit for HECI devices

[Subrata Banik (Code Review)]

Attention is currently required from: Tarun Tuli, Kapil Porwal, Sridhar Siricilla.

Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/69680 )

Change subject: soc/intel/meteorlake: Skip setting D0I3 bit for HECI devices
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Patch Set 3:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/69680/comment/dc309f9e_29ff489d 
PS2, Line 10: 
            : The learning being made from Alder Lake platform showed that the CSE
            : EOP cmd response time is highly nondeterministic and letting the EOP
            : cmd issued by FSP makes the response time even worse.
            : 
            : The idea being pursued during Alder Lake platform is to let FSP skip sending the EOP cmd and coreboot sends it at the last minute
            : (late sending of EOP) to ensure there is ample time for CSE to come
            : to a state where the response to the EOP is almost immediate.
> > > Can you please elaborate how the EOP cmd receiving arch is different between ADL and MTL?
> >
> > My comment is based on the issue you indicated in the CL's commit message. It seems the current commit message is not relevant directly.
>
> I have verified today that sending EOP using FSP is still taking longer time and even sending EOP late is no different. My conclusion is, the issue we have seen on ADL is still very much applicable on MTL.

I'm marking this comment resolved now and please move the discussion into mailing list or bug, whatever you prefer.