Attention is currently required from: Jérémy Compostella, Nicholas Chin, Subrata Banik.
Julius Werner 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 ......................................................................
Patch Set 14:
(1 comment)
Patchset:
PS4:
Acknowledged […]
Hmm... yeah, okay, this points out an important issue of this backend in combination with CONFIG_VBOOT_RETURN_FROM_VERSTAGE. The whole point of RETURN_FROM_VERSTAGE is that we can save SRAM and flash space by avoiding to link the CBFS and SPI driver code into verstage. Using this backend breaks all that.
I would say this patch should add `depends on !VBOOT_RETURN_FROM_VERSTAGE` to the USE_CBFS_FILE_OPTION_BACKEND option to prevent people from accidentally making that mistake. That means that it won't be usable on most Arm platforms, but I guess that's fine for now until someone starts finding a real need for it.
For the Intel boards, maybe just make it `default USE_CBFS_FILE_OPTION_BACKEND if CHROMEOS && PLATFORM_USES_FSP2_0` for now? Or select it in ChromeOS' downstream ebuilds for the appropriate boards instead.