From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25166 invoked by alias); 20 May 2009 15:34:21 -0000 Received: (qmail 25156 invoked by uid 22791); 20 May 2009 15:34:20 -0000 X-SWARE-Spam-Status: No, hits=-2.1 required=5.0 tests=AWL,BAYES_00,SPF_PASS X-Spam-Check-By: sourceware.org Received: from hagrid.ecoscentric.com (HELO mail.ecoscentric.com) (212.13.207.197) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 20 May 2009 15:34:13 +0000 Received: from localhost (hagrid.ecoscentric.com [127.0.0.1]) by mail.ecoscentric.com (Postfix) with ESMTP id 2901B60B8007; Wed, 20 May 2009 16:34:11 +0100 (BST) Received: from mail.ecoscentric.com ([127.0.0.1]) by localhost (hagrid.ecoscentric.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id kiuYlM+7owTe; Wed, 20 May 2009 16:34:09 +0100 (BST) Date: Wed, 20 May 2009 15:34:00 -0000 Message-Id: From: Bart Veer To: Andrew Lunn CC: gary@mlbassoc.com, andrew@lunn.ch, rutger@cs.vu.nl, ecos-devel@ecos.sourceware.org In-reply-to: <20090520142223.GM20046@lunn.ch> (message from Andrew Lunn on Wed, 20 May 2009 16:22:23 +0200) Subject: Re: NAND review References: <4A126D59.7070404@intefo.ch> <4A12B877.9030404@ecoscentric.com> <20090519141710.GJ20046@lunn.ch> <4A14083B.2040107@cs.vu.nl> <20090520135338.GL20046@lunn.ch> <4A140BEE.2060506@mlbassoc.com> <20090520142223.GM20046@lunn.ch> 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: 2009-05/txt/msg00060.txt.bz2 >>>>> "Andrew" == Andrew Lunn writes: Andrew> On Wed, May 20, 2009 at 07:55:58AM -0600, Gary Thomas wrote: >> Andrew Lunn wrote: >> >> FWIW, this is the approach taken by MTD with the BBT (Bad Block Table). >> > >> > Hi Rutger >> > >> > You seem to know the MTD code. How does MTD handle partition >> > information? Where does it get it from? >> >> It can be hard coded, come from the command line, or use the RedBoot >> FIS directory. (any or all of this set) Andrew> You could map these into eCos like concepts: Andrew> Hard code -> Hard coded Andrew> command line -> Redboot cfg block parameter? Andrew> FIS Directory -> FIS Directory! Andrew> I find it interesting that Linux guys consider FIS Andrew> directory usable, which is against what Bart was saying. The approach is usable iff you have NOR flash as well as NAND flash. Andrew> Putting that point aside, it does show that Linux Andrew> considers it necessary to have multiple ways of Andrew> configuring the partitions, so maybe eCos also needs Andrew> multiple ways of configuring partitions. To cope with systems which only have NAND flash, I think we must support hard-coding via configury. Hence that functionality must be implemented straightaway. It does not preclude adding other ways of specifying partitions in future, e.g. by storing them in NOR flash, if we feel that the added flexibility is worth the implementation effort and the code and data bloat. Obviously typically Linux developers will be less concerned about the latter than eCos developers. Bart