From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
Subject: Re: [RFC PATCH 3/9] of: mtd: add NAND timings retrieval support
Date: Thu, 9 Jan 2014 10:35:05 -0700
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To: boris brezillon <b.brezillon-ZNYIgs0QAGpBDgjK7y7TUQ@public.gmane.org>
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>, linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dev-3kdeTeqwOZ9EV1b7eY7vFQ@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Rob Landley <rob-VoJi6FS/r0vR7s880joybQ@public.gmane.org>, Grant Likely <grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>, David Woodhouse <dwmw2-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
List-Id: devicetree@vger.kernel.org

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