From s.popov@rsc.bg Tue Apr 28 17:01:43 2009 Received: from sigma.superhosting.bg ([91.196.124.10]) by stoneboat.aleph1.co.uk with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.69) (envelope-from ) id 1LypkY-0005GM-39 for yaffs@lists.aleph1.co.uk; Tue, 28 Apr 2009 17:01:43 +0100 Received: from blueice3n1.de.ibm.com ([195.212.29.179] helo=[9.157.146.18]) by sigma.superhosting.bg with esmtpsa (SSLv3:AES256-SHA:256) (Exim 4.69) (envelope-from ) id 1LypkR-0006qz-Oe for yaffs@lists.aleph1.co.uk; Tue, 28 Apr 2009 19:01:31 +0300 Message-ID: <49F72859.3050104@rsc.bg> Date: Tue, 28 Apr 2009 19:01:29 +0300 From: Stanislav Popov User-Agent: Thunderbird 2.0.0.21 (Windows/20090302) MIME-Version: 1.0 To: yaffs@lists.aleph1.co.uk Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - sigma.superhosting.bg X-AntiAbuse: Original Domain - lists.aleph1.co.uk X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - rsc.bg X-Source: X-Source-Args: X-Source-Dir: X-SA-Exim-Connect-IP: 91.196.124.10 X-SA-Exim-Mail-From: s.popov@rsc.bg X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on stoneboat.aleph1.co.uk X-Spam-Level: X-Spam-Status: No, score=-2.6 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.2.5 X-SA-Exim-Version: 4.2.1 (built Wed, 25 Jun 2008 17:14:11 +0000) X-SA-Exim-Scanned: Yes (on stoneboat.aleph1.co.uk) Subject: [Yaffs] NAND + YAFFS2 - bad blocks X-BeenThere: yaffs@lists.aleph1.co.uk X-Mailman-Version: 2.1.11 Precedence: list List-Id: Discussion of YAFFS NAND flash filesystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Apr 2009 16:01:43 -0000 Hi, I have 64 MB NAND flash on Jacinto (ARM) board. I am using the device formatted as one YAFFS2 partition. My SW ECC from NAND is enabled in the kernel and "useNANDECC" in YAFFS is set to 0 (If this is non-zero, then YAFFS will not perform ECC and it is assumed that the hardware ECC or specified NAND access functions will perform EC checks.) I found that I have 1000-2000 eraseblocks that were reported as "bad block". I can see them in u-boot with "nand bad" command and when laoding my nand_jacinto driver. When using the NAND they are getting much more. Actually they are NOT bad blocks! I edited the kernel and remove is_bad checking when erasing. Also I edited the mtd-utils (flash_eraseall) and removed is_bad checking when erasing. So I was able to make low-level format of my NAND flash which also erase the bad blocks. (like 'nand erase scrub' command in u-boot, but I currently I do not have such command) After that I had NO bad blocks. I made some tests: I formatted Nand with YAFFS2 FS - YAFFS2 ECC + NO NAND ECC - when using fs appeared bad blocks and getting more. - YAFFS2 NO ECC + NAND SW ECC - when using fs appeared bad blocks and getting more. I formatted Nand with EXT2 FS (ext2 fs is not writing into oob) - NAND SW ECC ENABLE - NO bad blocks appeared in the time!!! So the result is that the issue is in using YAFFS2 + NAND. Maybe the source of the issue is some YAFFS2 configurations? Do you have any idea? It's very critical issue for me. Thanks and Regards, Stanislav