From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 19922 invoked by alias); 13 Jun 2009 16:31:28 -0000 Received: (qmail 19872 invoked by uid 22791); 13 Jun 2009 16:31:26 -0000 X-SWARE-Spam-Status: No, hits=-1.7 required=5.0 tests=AWL,BAYES_05,SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: sourceware.org Received: from londo.lunn.ch (HELO londo.lunn.ch) (80.238.139.98) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sat, 13 Jun 2009 16:31:20 +0000 Received: from lunn by londo.lunn.ch with local (Exim 3.36 #1 (Debian)) id 1MFW8S-0002Gy-00; Sat, 13 Jun 2009 18:31:16 +0200 Date: Sat, 13 Jun 2009 16:31:00 -0000 From: Andrew Lunn To: Nick Garnett Cc: "ecos-devel@ecos.sourceware.org" Subject: Re: NAND review Message-ID: <20090613163115.GN5179@lunn.ch> References: <4A126D59.7070404@intefo.ch> <20090519162853.GA27459@lunn.ch> <20090603085115.GA27508@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-IsSubscribed: yes Mailing-List: contact ecos-devel-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-devel-owner@ecos.sourceware.org X-SW-Source: 2009-06/txt/msg00023.txt.bz2 > It is sometimes best to think about a concrete example, and my > thoughts on NAND use were informed by thinking about how to use the > NAND on an Atmel AT91SAM9 based device. I agree with the sentiment. Lets take another couple of examples. Both Rutger and Simon have NOR flash to boot from. They will put one filesystem onto the NAND device. For them partitioning is just bloat. I think that should be a strong argument for having an API which does not enforce the use of partitions. http://pokylinux.org/releases/pinky-3.1/readme.hardware The freescale ADS section talks about using NAND devices and putting the partition table in the FIS directory. I found other freescale extensions for Redboot, but most information seems to require that you register. However it looks like Freescale have a redboot which fully integrated NAND devices into FIS and FIS can be used to partition the flash. Your argument about the HAL knowing about the boot block sections makes a lot of sense. However i think we need an architecture where additional partition information can come from other places. FIS, or a NandFIS would be one such other place. We also need to think about how this information is exported, eg into file systems, to Linux, and to RAM versions of eCos running on top of ROM or ROMRAM Redboot etc. Andrew