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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [PATCH 2/2] [POWERPC] Describe memory-mapped RAM&ROM chips of
	bindings
Date: Wed, 26 Mar 2008 15:52:37 +0100
To: Laurent Pinchart <laurentp@cse-semaphore.com>
Cc: ben@simtec.co.uk, linuxppc-dev@ozlabs.org, linux-mtd@lists.infradead.org,
	David Gibson <david@gibson.dropbear.id.au>
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> +    Dedicated RAM and ROM chips are often used as storage for 
> temporary or
> +    permanent data in embedded devices. Possible usage include 
> non-volatile
> +    storage in battery-backed SRAM, semi-permanent storage in 
> dedicated SRAM
> +    to preserve data accross reboots and firmware storage in 
> dedicated ROM.
> +
> +     - compatible : should contain the specific model of RAM/ROM 
> chip(s)
> +       used, if known, followed by either "physmap-ram" or 
> "physmap-rom"
> +     - reg : Address range of the RAM/ROM chip
> +     - bank-width : Width (in bytes) of the RAM/ROM bank. Equal to the
> +       device width times the number of interleaved chips.
> +     - device-width : (optional) Width of a single RAM/ROM chip. If
> +       omitted, assumed to be equal to 'bank-width'.

Maybe I'm rehashing some old discussion here, if so, sorry; but why
do you have bank-width and device-width here?  What useful information
does it provide?  If this is about saying what the preferred (or only
possible) access width is, better names are in order.


Segher