From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Thu, 9 Jan 2014 10:35:05 -0700
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: boris brezillon <b.brezillon@overkiz.com>
Subject: Re: [RFC PATCH 3/9] of: mtd: add NAND timings retrieval support
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Cc: devicetree@vger.kernel.org, Russell King <linux@arm.linux.org.uk>,
 linux-doc@vger.kernel.org, dev@linux-sunxi.org, linux-kernel@vger.kernel.org,
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On Thu, Jan 09, 2014 at 09:36:18AM +0100, boris brezillon wrote:

> >You might want to check if you can boil down the DT timings from the
> >huge list to just an ONFI mode number..
> 
> Sure, but the sunxi driver needs at least 19 of them...

So does mvebu's NAND driver..

What I ment was you could have a

  onfi,nand-timing-mode = 0

in the DT. Each of the modes defines all ~19 parameters, higher modes
are faster.

Pick a mode value that fits all the parameters of the connected
non-ONFI flash.

This would be instead of defining each parameter
individually.. Provide some helpers to convert from a onfi mode number
to all the onfi defined timing parameters so that drivers can
configure the HW..

Jason