[coreboot-gerrit] [L] Change in coreboot[master]: mb/google/rex: Enable ISH support

[Subrata Banik (Code Review)]

Attention is currently required from: Bernardo Perez Priego, Boris Mittelberg, Caveh Jalali, Gwendal Grignou, Harsha B R, Jamie Ryu, Jay Patel, Kapil Porwal, Li1 Feng, Paul Menzel, Tarun Tuli, Vijay P Hiremath, Wonkyu Kim.

Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/75039?usp=email )

Change subject: mb/google/rex: Enable ISH support
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Patch Set 13:

(1 comment)

File src/mainboard/google/rex/Kconfig:

https://review.coreboot.org/c/coreboot/+/75039/comment/9bdc062b_73d88a76 :
PS13, Line 111: 	default "variants/$(CONFIG_VARIANT_DIR)/overridetree_ec_ish.cb" if DRIVERS_INTEL_ISH
> I would think so. Including the ISH into devicetree requires `DRIVERS_INTEL_ISH`, which is only selected by `BOARD_GOOGLE_REX_EC_ISH`. See [75470/Kconfig.name](https://review.coreboot.org/c/coreboot/+/75470/2/src/mainboard/google/rex/Kc...)
>
> The change below in overridetree.cb without `DRIVERS_INTEL_ISH` causes build failure.
>    device ref ish on
>    	probe ISH ISH_ENABLE
>    	chip drivers/intel/ish
>    		register "firmware_name" = ""rex_ish.bin""
>    		device generic 0 on end
>    	end
>    end

the cost of maintaining different override*.cb is too much. I would rather suggest to move DRIVERS_INTEL_ISH under both rex0 and rex_ec_ish and keep only one *.cb override file.