[PATCH] powerpc: Create "rom" (MTD) device prpmc2800

David Gibson david at gibson.dropbear.id.au
Fri Jun 15 14:14:23 EST 2007


On Thu, Jun 07, 2007 at 05:55:44PM +0200, Segher Boessenkool wrote:
> > 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?

Slight revision suggestion.  Can we make 'device-width' optional, with
the default value being equal to the bank-width?

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson



More information about the Linuxppc-dev mailing list