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Date:   Fri, 6 Apr 2018 14:47:13 +0100
From:   Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To:     Aaron Durbin <adurbin@chromium.org>
Cc:     Andy Shevchenko <andy.shevchenko@gmail.com>,
        Daniel Kurtz <djkurtz@chromium.org>,
        Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>,
        Marc Gonzalez <marc_gonzalez@sigmadesigns.com>,
        Doug Anderson <dianders@chromium.org>,
        Matt Redfearn <matt.redfearn@mips.com>,
        Jeffy <jeffy.chen@rock-chips.com>,
        "open list:SERIAL DRIVERS" <linux-serial@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/3] serial: 8250_early: Add earlycon support for AMD
 Carrizo / Stoneyridge
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> 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 ?

Alan