Martin Roth has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/33380 )
Change subject: Console: Allow console UART to be enabled without serial console ......................................................................
Patch Set 1:
(3 comments)
Patch Set 1:
Sorry for the basic question, but: What does this fix?
If this is needed to make something work in the OS, I guess something at the chip level is accidentally guarded by SERIAL_CONSOLE? At least the code in drivers/uart/ shouldn't make any difference regarding the general availability of the UART.
This is just to set up the UAER even if coreboot doesn't use it. This also goes along with the following patches to set up the SPCR ACPI table.
https://review.coreboot.org/#/c/33380/1/src/drivers/uart/Kconfig File src/drivers/uart/Kconfig:
https://review.coreboot.org/#/c/33380/1/src/drivers/uart/Kconfig@4 PS1, Line 4: config ENABLE_UART
nit: why not just make this option directly menuconfig-visible? I think it would have the same effec […]
This should be separate because this symbol can be turned on by selecting the serial console. At that point, it's not a change that gets saved in defconfig.
Right now, if you select ENABLE_UART_WITHOUT_CONSOLE, that gets saved in a defconfig, regardless of the state of the serial console option.
https://review.coreboot.org/#/c/33380/1/src/drivers/uart/Kconfig@12 PS1, Line 12: The primary UART has previously only been set up when the serial console
nit: I think explaining how older versions used to work is confusing and somewhat irrelevant here... […]
I'll update it.
https://review.coreboot.org/#/c/33380/1/src/include/console/uart.h File src/include/console/uart.h:
https://review.coreboot.org/#/c/33380/1/src/include/console/uart.h@70 PS1, Line 70: #if CONFIG(ENABLE_UART)
This is changing the effect for (ENV_SMM && !CONFIG(DEBUG_SMI)). […]
It shouldn't matter if it gets enabled in a stage that doesn't call it. I could specifically exclude it in verstage, postcar, and SMM, but I don't think that will actually change anything.