From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <segher@kernel.crashing.org>
In-Reply-To: <1186438523.938.83.camel@localhost.localdomain>
References: <20070730150648.GA5005@ru.mvista.com>
	<20070801020836.GB31391@localhost.localdomain>
	<65ff446478a9fd0a48061079d5f04f8f@kernel.crashing.org>
	<20070801050422.GI31391@localhost.localdomain>
	<20070801054751.GM31391@localhost.localdomain>
	<46B1F6D4.3070707@ru.mvista.com>
	<20070803031349.GD6418@localhost.localdomain>
	<46B34E1F.5060009@ru.mvista.com>
	<20070806042109.GB6103@localhost.localdomain>
	<46B76A5A.3030300@ru.mvista.com>
	<1186438523.938.83.camel@localhost.localdomain>
Mime-Version: 1.0 (Apple Message framework v623)
Content-Type: text/plain; charset=US-ASCII; format=flowed
Message-Id: <30b543242f076847597582b8589dadec@kernel.crashing.org>
From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [PATCH 2/6] PowerPC 440EPx: Sequoia DTS
Date: Tue, 7 Aug 2007 01:09:22 +0200
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@ozlabs.org, David Gibson <david@gibson.dropbear.id.au>
List-Id: Linux on PowerPC Developers Mail List <linuxppc-dev.ozlabs.org>
List-Unsubscribe: <https://ozlabs.org/mailman/listinfo/linuxppc-dev>,
	<mailto:linuxppc-dev-request@ozlabs.org?subject=unsubscribe>
List-Archive: <http://ozlabs.org/pipermail/linuxppc-dev>
List-Post: <mailto:linuxppc-dev@ozlabs.org>
List-Help: <mailto:linuxppc-dev-request@ozlabs.org?subject=help>
List-Subscribe: <https://ozlabs.org/mailman/listinfo/linuxppc-dev>,
	<mailto:linuxppc-dev-request@ozlabs.org?subject=subscribe>

>>     Actually, checking for the presence of all possible perverted
>> mapping
>> props doesn't seem a good idea -- it's simpler to check for the
>> presence of
>> one prop (like "direct-mapped" I was thinking about, or maybe
>> "simple-map").
>
> Or more simply... if it's not a direct mapping, it doesn't have a 
> ranges
> property and can't be walked down by conventional means.

That establishes that the flash address space is mapped 1-1 into
the host address space; however it doesn't say anything about
swizzling or interleaving or endianness etc., which are important
for NOR flash memory because of how the command sets work.


Segher