[M] Change in coreboot[main]: drivers/option: Add CBFS file based option backend

[Subrata Banik (Code Review)]

Attention is currently required from: Julius Werner, Nicholas Chin.

Subrata Banik has posted comments on this change by Nicholas Chin. ( https://review.coreboot.org/c/coreboot/+/85905?usp=email )

Change subject: drivers/option: Add CBFS file based option backend
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Patch Set 9:

(2 comments)

Patchset:

PS2:
> @[e-mail] If it makes things easier feel free to push new patchsets. I won't be able to get back to this until later in the day.

thanks, I believe we are good now. thanks for addressing the review comments

File src/drivers/option/Makefile.mk:

https://review.coreboot.org/c/coreboot/+/85905/comment/950c4b63_6a4b7de2?usp... :
PS6, Line 6: smm-$(CONFIG_USE_CBFS_FILE_OPTION_BACKEND) += cbfs_file_option.c
> Seems like the only user of the option api in SMM is the `power_on_after_fail` option, which defaults to a a value that can be set by Kconfig. So there isn't much lost by removing the ability to configure options in SMM, and keeping SMM as simple as possible and having fewer possible SMM runtime codepaths is probably not a bad idea anyway.

I agree with you that pmclib.c is the only consumer where we can directly assign Kconfig value. we might not need an option there. It would eliminate the need for compiling option API for smm mode