Attention is currently required from: Furquan Shaikh, Paul Menzel, Patrick Rudolph. Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55224 )
Change subject: soc/intel/skylake: Auto-configure SerialIoDevMode UPD ......................................................................
Patch Set 1:
(2 comments)
File src/soc/intel/skylake/Kconfig:
https://review.coreboot.org/c/coreboot/+/55224/comment/9f839272_4d20e41c PS1, Line 180: DERIVE_SERIALIO_CFG_FROM_DEV_STATE
Is this Kconfig required?
It's necessary for now, but can be removed once all mainboards select it. Having it allows adapting each board in a separate commit, which is useful because some boards may have inconsistencies (between SerialIoDevMode values and device states).
The change looks like the direction we would want to go in for all mainboards i.e. eliminate the devicetree config and instead rely on SoC determining the correct values for the UPDs based on device state in devicetree and other configs.
I fully agree.
https://review.coreboot.org/c/coreboot/+/55224/comment/b7a254c9_3f34c351 PS1, Line 186: When enabled, the `SerialIoDevMode` setting in chip config is useless.
It’d make it the other way around `EXPLICIT_SERIALIO_CFG`, so boards needing this have to select it.
Usually, I would agree. However, doing so in this commit means that all boards except hp/280_g2 would have to select `EXPLICIT_SERIALIO_CFG`, which would be rather noisy. Plus, if we're going to update all mainboards to not use `SerialIoDevMode` in the devicetree (see Furquan's comment), we will end up removing the Kconfig option altogether.