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From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Tue, 16 Jan 2024 15:13:42 +0100
Message-ID: <CAMuHMdU0qtMeX=7SY+32=30-QGMRniFVCCm217REJ1X+ZNJ=Aw@mail.gmail.com>
Subject: Re: [PATCH 1/6] arm64: Unconditionally call unflatten_device_tree()
To: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Boyd <sboyd@kernel.org>, Rob Herring <robh+dt@kernel.org>, linux-kernel@vger.kernel.org, 
	patches@lists.linux.dev, linux-um@lists.infradead.org, 
	linux-arm-kernel@lists.infradead.org, kunit-dev@googlegroups.com, 
	linux-kselftest@vger.kernel.org, devicetree@vger.kernel.org, 
	Frank Rowand <frowand.list@gmail.com>, Catalin Marinas <catalin.marinas@arm.com>, 
	Will Deacon <will@kernel.org>
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Hi Mark,

On Tue, Jan 16, 2024 at 12:51=E2=80=AFPM Mark Rutland <mark.rutland@arm.com=
> wrote:
> On Fri, Jan 12, 2024 at 12:07:44PM -0800, Stephen Boyd wrote:
> > Call this function unconditionally so that we can populate an empty DTB
> > on platforms that don't boot with a firmware provided or builtin DTB.
> > There's no harm in calling unflatten_device_tree() unconditionally.
>
> For better or worse, that's not true: there are systems the provide both =
a DTB
> *and* ACPI tables, and we must not consume both at the same time as those=
 can
> clash and cause all sorts of problems. In addition, we don't want people =
being
> "clever" and describing disparate portions of their system in ACPI and DT=
.

We'd get to the latter anyway, when plugging in a USB device where the
circuitry on/behind the USB device is described in DT.

Gr{oetje,eeting}s,

                        Geert

--=20
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k=
org

In personal conversations with technical people, I call myself a hacker. Bu=
t
when I'm talking to journalists I just say "programmer" or something like t=
hat.
                                -- Linus Torvalds