From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dave Martin <dave.martin-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Subject: Re: [RFC PATCH 2/2] ARM: DT: kernel: DT cpu node bindings update
Date: Tue, 16 Apr 2013 15:30:18 +0100
Message-ID: <20130416143018.GB2229@linaro.org>
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To: Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
Cc: Nicolas Pitre <nicolas.pitre-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Jon Medhurst <tixy-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Andrew Lunn <andrew-g2DYL2Zd6BY@public.gmane.org>, Sekhar Nori <nsekhar-l0cyMroinI0@public.gmane.org>, Viresh Kumar <viresh.kumar-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Kukjin Kim <kgene.kim-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Lennert Buytenhek <kernel-OLH4Qvv75CYX/NnBR394Jw@public.gmane.org>, Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>, Magnus Damm <magnus.damm-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Catalin Marinas <catalin.marinas-5wv7dgnIgG8@public.gmane.org>, David Brown <davidb-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>, devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>, Simon Horman <horms-/R6kz+dDXgpPR4JQBCEnsQ@public.gmane.org>, Barry Song <baohua.song-kQvG35nSl+M@public.gmane.org>, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Amit Kucheria <amit.kucheria-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
List-Id: devicetree@vger.kernel.org

On Mon, Apr 15, 2013 at 01:26:02PM -0600, Stephen Warren wrote:
> On 04/15/2013 10:13 AM, Lorenzo Pieralisi wrote:

[...]

> > +	- enable-method
> > +		Usage: required on ARM 64-bit systems, optional on ARM 32-bit
> > +		       systems

If we define no meaningful enumerations for 32-bit systems (for example,
the spin-table boot method doesn't exist), then arguably this property
should be prohibited for 32-bit systems in this version of the binding.

The binding should be extended later when we have enable methods to add?

(enable-method = "psci" is one plausible addition)

> > +		Value type: <string>
> > +		Definition: On ARM 64-bit systems must be "spin-table" [1].
> 
> Can that be an integer instead? with dtc+cpp support, that shouldn't
> hurt the eyes too much any more.

That doesn't feel very DT-like, and it makes the standalone FDT excessively
cryptic without the headers.  Does it really matter that much?  DT parsing
should not be on any performance-critical path.

Mostly, DT convention seems to be to use legible string names for
enumerations like this.

Anything which tends to encrypt the DT content starts us on a slippery
slope IMHO.  Converting the DT back to a vaguely human-readable form
becomes impossible without the headers.

Cheers
---Dave