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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [PATCH] powerpc: Create "rom" (MTD) device prpmc2800
Date: Thu, 7 Jun 2007 17:55:44 +0200
To: David Woodhouse <dwmw2@infradead.org>
Cc: linuxppc-dev@ozlabs.org, linux-mtd@lists.infradead.org,
	Milton Miller <miltonm@bga.com>
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> Any representation of flash devices in the device-tree should ideally
> have 'bus width' and 'interleave' properties to contain this
> information.
>
> The 'bus width' cannot necessarily be inferred, especially where a 
> given
> bus can be configured to allow multiple sizes of access. It's purely a
> function of how the flash chips are wired up. That's why we actually
> call it 'bank width', not 'bus width' in the Linux code.

Ah, "bank width" as in "bus width" per chip select.  I see.

So I think the best thing to have would be

	compatible      "cfi-flash"
	bank-width      like you said
	device-width    width of a single flash device
	reg             complete address range of this thing

and then the Linux OF CFI flash code / MTD code just keeps
on probing devices from that address range until it has it
filled.

Sounds good / comments / anything I missed?


Segher