Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/47826 )
Change subject: soc/amd/picasso/acpi/sb_fch: add SPI controller ......................................................................
Patch Set 1: Code-Review-1
Patch Set 1:
Unfortunately, the OS can't really use the spi controller for anything because there's no hardware arbitration. Any reads to the SPI ROM's memory address will automatically get sent out over the spi bus to the Firmware ROM, messing up any transactions if there were another device on the SPI bus.
Because of that, I think it's better just not to even tell the OS about the spi controller.
oh, you might have a point there. I'll add a -1, so that it won't accidentally get merged for now; not sure when I'll get around to have a close look into this