From: Arnd Bergmann <arnd@arndb.de>
To: linux-arm-kernel@lists.infradead.org
Cc: Pali =?ISO-8859-1?Q?Roh=E1r?= <pali.rohar@gmail.com>,
        Rob Herring <robherring2@gmail.com>,
        Russell King <linux@arm.linux.org.uk>,
        Will Deacon <will.deacon@arm.com>,
        Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>,
        Sebastian Reichel <sre@debian.org>, Pavel Machek <pavel@ucw.cz>,
        Tony Lindgren <tony@atomide.com>,
        Andreas =?ISO-8859-1?Q?F=E4rber?= <afaerber@suse.de>,
        linux-omap@vger.kernel.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        devicetree@vger.kernel.org
Subject: Re: [RESEND] [PATCH v2 1/2] arm: devtree: Set system_rev from DT revision
Date: Wed, 06 May 2015 11:31:15 +0200
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On Wednesday 06 May 2015 10:49:01 Pali Roh?r wrote:
> With this patch "revision" DT string entry is used to set global system_rev
> variable. DT "revision" is expected to be string with one hexadecimal number.
> So "Revision" line in /proc/cpuinfo will be same as "revision" DT value.
> 
> Signed-off-by: Pali Roh?r <pali.rohar@gmail.com>
> Acked-by: Pavel Machek <pavel@ucw.cz>

+devicetree mailing list

The property needs to be specified in a binding somewhere.

> @@ -246,5 +247,14 @@ const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys)
>  	/* Change machine number to match the mdesc we're using */
>  	__machine_arch_type = mdesc->nr;
>  
> +	/* Set system revision from DT */
> +	prop = of_get_flat_dt_prop(dt_root, "revision", &size);
> +	if (prop && size > 0) {
> +		char revision[11];
> +		strlcpy(revision, prop, min(size, (int)sizeof(revision)));
> +		if (kstrtouint(revision, 16, &system_rev) != 0)
> +			system_rev = 0;
> +	}
> +
>  	return mdesc;
>  }
> 

What is the reason for doing it this early? I think it would be nicer to do
it after unflattening the DT.

Also, it seems strange to have a string property and then use kstrtouint
to convert it into a number. I think it should either be specified in a DT
binding to be a string and then have the kernel not assume that it is a number,
or we should define it to be binary.

	Arnd
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