[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <CAD=FV=WmqDSbnA8OWL00WS-qc9A4wCpkgxHhLBW3qEE=SkzupA@mail.gmail.com>
Date: Wed, 30 Sep 2015 16:58:43 -0700
From: Doug Anderson <dianders@...omium.org>
To: Krzysztof Kozlowski <k.kozlowski@...sung.com>
Cc: Javier Martinez Canillas <javier@....samsung.com>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
Mauro Carvalho Chehab <mchehab@....samsung.com>,
Olof Johansson <olof@...om.net>,
Russell King <linux@....linux.org.uk>,
Kukjin Kim <kgene@...nel.org>,
"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
Kumar Gala <galak@...eaurora.org>,
Ian Campbell <ijc+devicetree@...lion.org.uk>,
linux-samsung-soc <linux-samsung-soc@...r.kernel.org>,
Rob Herring <robh+dt@...nel.org>,
Pawel Moll <pawel.moll@....com>,
Mark Rutland <mark.rutland@....com>,
"linux-arm-kernel@...ts.infradead.org"
<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH] ARM: dts: Add Exynos5250 Snow Rev5+ support
Hi,
On Wed, Sep 30, 2015 at 4:44 PM, Krzysztof Kozlowski
<k.kozlowski@...sung.com> wrote:
>> Switching the default meaning of "google,snow" to Rev5 is probably not
>> something we'd ever want to do, since it could confuse "rev3" boards
>> (which should be serviced by the rev4 dts). From comments in the
>> Chrome OS tree:
>>
>> In the "rev4" DTS:
>> * - Any real rev 0-3 boards in the field will match "google,snow",
>> * since older U-Boots don't look for a revision specific device tree.
>> * - Any real rev 4 boards in the field will match "google,snow-rev4"
>> * first. If that's not present they will pick the first
>> * "google,snow" device tree that they find (ignoring the kernel
>> * ordering).
>>
>> In the "rev5" DTS:
>> * - Purposely don't add "google,snow" so old firmware (which didn't
>> * include a -revN suffix) won't pick this one.
>
> These are requirements written somewhere in the downstream tree... not
> in upstream. Have in mind that someone may not be using Chrome OS on
> Chromebook but custom U-Boot and different distro.
>
> You cannot expect that everyone will new some requirements of some
> downstream OS. If you need such requirements, write them in bindings
> documentation *in the upstream*.
Agreed, which is why I bring it up here. I think Javier wasn't aware
of these when he sent up his patch. I believe when he adds the
bindings docs he'll put this information.
Previously rev5 wasn't supported upstream and I believe rev5 didn't
even exist when the upstream stuff was submitted.
-Doug
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists