[XS] Change in coreboot[main]: intel/alderlake: Remove FSP_PUBLISH_MBP_HOB config for RPL

[Subrata Banik (Code Review)]

Attention is currently required from: Dinesh Gehlot, Kapil Porwal, Kilari Raasi, Nick Vaccaro, Paul Menzel, Ronak Kanabar.

Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81446?usp=email )

Change subject: intel/alderlake: Remove FSP_PUBLISH_MBP_HOB config for RPL
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Patch Set 2:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/81446/comment/c036dcea_576cff84 :
PS2, Line 8: 
           : By removing FSP_PUBLISH_MBP_HOB for RPL SkipMbpHob is set to 0.
           : And it prevents the boot time increase of ~158ms.
i guess you are presenting the twisted fact here, ideally we wish to avoid sending MBP cmd and create HOB to save boot time. Based on our experience it saves 10-20ms of boot time. CB:71873

Now, Intel CSE has been experiencing some boot delay without sending MBP cmd due to some other issue (which is yet to debug) and setting SkipMbpHob=0 is helping Intel CSE/FSP to avoid additional boot penalty.

Ideally, we should be root causing why SkipMbpHob=1 is causing the issue all of a sudden.

Until then please specify this is a W/A and not final fix.

https://review.coreboot.org/c/coreboot/+/81446/comment/3b15750c_aa3b6872 :
PS2, Line 18: With
without

File src/soc/intel/alderlake/Kconfig:

https://review.coreboot.org/c/coreboot/+/81446/comment/5a6466b7_af503f71 :
PS2, Line 529: RPL
consider changing this now?