From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dell-paw-3.cambridge.redhat.com ([195.224.55.237] helo=passion.cambridge.redhat.com) by pentafluge.infradead.org with esmtp (Exim 3.22 #1 (Red Hat Linux)) id 15U9Cg-0007oG-00 for ; Tue, 07 Aug 2001 16:55:34 +0100 From: David Woodhouse In-Reply-To: References: To: "James, Laura" Cc: linux-mtd@lists.infradead.org Subject: Re: Problems with NAND support Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 07 Aug 2001 17:01:22 +0100 Message-ID: <19639.997200082@redhat.com> Sender: linux-mtd-admin@lists.infradead.org Errors-To: linux-mtd-admin@lists.infradead.org List-Help: List-Post: List-Subscribe: , List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: laurajames@attlabs.att.com said: > We're going to be working on a new board with large amounts of NAND > flash in the immediate future. It would seem to be a much better idea > to go with jffs2 than jffs. What will we need to do to get it > working? > Any pointers you can give will be very much appreciated. Mainly: 1. Deal with the 10-write-per-page restriction on NAND chips. Probably just by keeping track of the number of writes to a page and when dishing out the tenth chunk (which will be rare, most nodes will be greater than 1/10 of a page) mark the remainder of the page as obsolete. 2. Ideally, we should do ECC instead of just the CRC we have at the moment. We need to invent two new node types with ECC to parallel the original inode and dirent nodes. 3. Be better about detecting bad blocks and treating them appropriately. -- dwmw2