From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7540 invoked by alias); 13 May 2009 13:59:01 -0000 Received: (qmail 7528 invoked by uid 22791); 13 May 2009 13:58:59 -0000 X-SWARE-Spam-Status: No, hits=0.5 required=5.0 tests=AWL,BAYES_05,J_CHICKENPOX_45,J_CHICKENPOX_93,SPF_PASS,SUBJ_ALL_CAPS 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, 13 May 2009 13:58:54 +0000 Received: from localhost (hagrid.ecoscentric.com [127.0.0.1]) by mail.ecoscentric.com (Postfix) with ESMTP id D524660B8002; Wed, 13 May 2009 14:58:49 +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 kAifhbLeyg0V; Wed, 13 May 2009 14:58:48 +0100 (BST) Message-ID: <4A0AD212.60208@ecoscentric.com> Date: Wed, 13 May 2009 13:59:00 -0000 From: Ross Younger User-Agent: Thunderbird 2.0.0.21 (X11/20090318) MIME-Version: 1.0 To: ecos-maintainers@ecos.sourceware.org CC: Rutger Hofman , Simon Kallweit , Sergei Gavrikov Subject: NAND & YAFFS Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Mailing-List: contact ecos-maintainers-help@ecos.sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: ecos-maintainers-owner@ecos.sourceware.org X-SW-Source: 2009-05/txt/msg00007.txt.bz2 Dear maintainers, We (eCosCentric) have been working on a NAND layer for eCos and integration with YAFFS, which we intend to contribute. Unfortunately, due to commercial considerations - including licensing and technical discussions with Aleph One - we have previously had to keep quiet about it. We can now talk about this work publicly, and would like to explore how the best overall solution for the eCos project can be pulled together. Obviously two alternative implementations and further duplication of work is best avoided, so we have opened a discussion with Rutger to see if there are ways in which we can work together to try and find a common "best of breed" technical solution. It seems sensible that the maintainers are aware of this discussion and have the opportunity to provide input and direction. A quick overview of our status: * We have developed a NAND interface library, drivers for a single chip+board combination and a synthetic pseudo-device, and an adaptation layer to bring YAFFS into eCos via the fileio layer. Specific further support for RedBoot is also in the works. * The NAND layer is complete and fully documented; YAFFS integration is approaching completion. * Written testcases exist for the NAND layer and YAFFS, and they will be subject to the same rigorous in-house automated test processes we use for all eCosPro code. * All of our code is intended to be contributed back to eCos, except of course the GPL parts of YAFFS itself. We have included in our plan building YAFFS as a separate .epk file so users who are happy with the GPL can easily download it and install using ecosadmin.tcl. We had looked at Rutger's early work, but decided against using it. Part of the reason for this was that integrating alpha code from other sources is always difficult, and we were (still are) operating under commercial time pressures. It would have been difficult for us to go public before now without sounding like we were taking advantage of Rutger's work, or compromising the project's earlier need for confidentiality. There were also some technical considerations; our NAND library has fewer layers, and our YAFFS integration is subtly different. Please let me know your thoughts. I can provide an interim documentation or code drop if you'd like to see one. (The NAND layer is complete; YAFFS is still being worked on, and RedBoot will be next.) Regards, Ross -- Embedded Software Engineer, eCosCentric Limited. Barnwell House, Barnwell Drive, Cambridge CB5 8UU, UK. Registered in England no. 4422071. www.ecoscentric.com