From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lazybastard.de ([212.112.238.170] helo=longford.lazybastard.org) by bombadil.infradead.org with esmtps (Exim 4.68 #1 (Red Hat Linux)) id 1Izikj-00015q-Vl for linux-mtd@lists.infradead.org; Wed, 05 Dec 2007 01:08:48 +0000 Date: Wed, 5 Dec 2007 02:03:18 +0100 From: =?utf-8?B?SsO2cm4=?= Engel To: Kyungmin Park Subject: Re: [RFC][PATCH][JFFS2] JFFS2 doesn't use OOB at MLC NAND/OneNAND Message-ID: <20071205010318.GG26112@lazybastard.org> References: <20071205005553.GA28782@party> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20071205005553.GA28782@party> Cc: dwmw2@infradead.org, linux-mtd@lists.infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 5 December 2007 09:55:53 +0900, Kyungmin Park wrote: > > It's the preparation patch for the MLC NAND/OneNAND flash. > The current jffs2 implementation at NAND case uses the NOP 2, cleanmarker and data each page 0. It breaks the NOP 1 limitation in MLC flash. > > With this patch, we don't write the cleanmarker at oob area. > I'm not sure it should use the cleanmarker at data area as NOR does. > Apart from the cleanmarker, there's serious POR issue, paired page at MLC. > > The paired page problem is that if the some page is broken, the paired page is also broken even though it is written correctly at previous time. > That's the reason the cleanmarker is not big issue at this time. > > Now we support the NOP 1 and later we have to address this paired page issue. I'm not sure when this problem is addressed. > > Any comments are welcome. I like it. Jörn -- Joern's library part 3: http://inst.eecs.berkeley.edu/~cs152/fa05/handouts/clark-test.pdf