Re: [PATCH 1/3] serial: 8250_early: Add earlycon support for AMD Carrizo / Stoneyridge

[Aaron Durbin]

On Fri, Apr 6, 2018 at 7:47 AM, Alan Cox <gnomes@xxxxxxxxxxxxxxxxxxx> wrote:
>> But we don't have the full ACPI interpreter up in the early part of
>> the kernel. All these 'early' devices have their own setup/config
>> which is the source of the issue. Or maybe I am wrong about the full
>> interpreter and the early drivers are just not taking advantage of the
>> ACPI device binding?
>
> In very early boot with serial console you just have to pray. No change
> there. Once ACPI comes up you however have the information to populate
> everything and configure correctly.
>
> So it should work fine except for kernel hackers trying to do early boot
> debug, which is a small (but important) cornercase ?

Yes, I think we're on the same page. This patch series is trying to
get the early console working correctly given the current code
assumptions.

-Aaron