From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from trinity.fluff.org ([217.147.94.151]) by canuck.infradead.org with esmtps (Exim 4.63 #1 (Red Hat Linux)) id 1HnpjF-0004Zz-Ov for linux-mtd@lists.infradead.org; Tue, 15 May 2007 01:37:46 -0400 Date: Tue, 15 May 2007 06:37:28 +0100 To: Harald Welte Subject: Re: ECC on 2048 byte page size 8-bit NAND on Samsung S3C2440 Message-ID: <20070515053727.GF805@trinity.fluff.org> References: <20070515003039.GB32448@prithivi.gnumonks.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070515003039.GB32448@prithivi.gnumonks.org> From: Ben Dooks Cc: linux-mtd@lists.infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, May 15, 2007 at 08:30:40AM +0800, Harald Welte wrote: > Hi! > > On openmoko's future mobile communications devices, we're using 2048 > byte page sized NAND chips (x8 organization such as K9F8G08U0A). > > However, it seems to me that the ECC support for 2048byte page sized > NAND chips is not really implemented yet, neither by the NAND core, nor > by the S3C2440 NAND driver. > > As far as I understand it (I haven't worked with 2k page before), the > 2440 NAND controller can generate a 4-byte ECC for each 2048byte page (8 > bytes in case of x16 organization, this seems somehow strange). > > In addition to ECC on the actual main data area, it also supports ECC on > the OOB data, too. I haven't found any piece of code in any other NAND > driver in the kernel that uses this feature. > > Also, I don't see something like a standard ECC layout for the 2048byte > page deivces. Is there one? > > I can certainly spend my time hacking up some working code. The > quesetion is if there is already some thought by one of the people > involved for some longer time with linux-mtd and/or the s3c2440. > > So if you have implementation thoughts / wishes / guidelines: THis is > the time to raise them, before I just doo what I deem appropriate ;) Hi. we're in the process of upgrading to large page nand ourselves, expect patches released before the end of the week, we're just doing QA on our patchset and updating our release tool. -- Ben Q: What's a light-year? A: One-third less calories than a regular year.