[coreboot-gerrit] Change in coreboot[master]: console: Override coreboot log level via VPD variable

[Johnny Lin (Code Review)]

Johnny Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/45134 )

Change subject: console: Override coreboot log level via VPD variable
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Patch Set 3:
> Patch Set 2:
> > Patch Set 2:
> > > Patch Set 2:
> > >
> > > I guess this could be moved to some generic location?
> >
> > Maybe drivers/vpd or src/console and add a new config option for this?
>
> src/console makes more sense to me. The input may be come from VPD, or something else (depending on platform). So:
> Use the CONFIG_DEFAULT_CONSOLE_LOGLEVEL_* as default.
> If CONFIG_CONSOLE_LOGLEVEL_OVERRIDE is defined, call a platform specific function to get the desired log level, and use it.
> Deltalake platform code implements the platform specific function which queries COREBOOT_LOG_LEVEL vpd variable.

CONFIG_CONSOLE_LOGLEVEL_OVERRIDE and CONFIG_DEFAULT_CONSOLE_LOGLEVEL_* are mutual exclusive, so I need to add CONSOLE_VPD_DEFAULT_LOGLEVEL as the fallback default loglevel. Added loglevel_vpd.c to be the general code instead of mainboard-specific implementation per Patrick's request.