From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from osdsun1.nrl.navy.mil ([132.250.130.7]) by canuck.infradead.org with esmtp (Exim 4.33 #1 (Red Hat Linux)) id 1BaglJ-0000xy-VE for linux-mtd@lists.infradead.org; Wed, 16 Jun 2004 16:12:01 -0400 Message-ID: <083701c453df$c65db960$0100a8c0@superfortress> From: "Dan Brown" To: "Slim" , References: <20040616161345.33330.qmail@web50802.mail.yahoo.com> Date: Wed, 16 Jun 2004 16:23:24 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: Subject: Re: [PATCH] Towards DiskOnChip support as a NAND driver List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , A few answers: > Is the doc2000 dip NFTL or INFTL? With read only support, would I be > able to create a filesystem to read? Some are NFTL, some are INFTL. The INFTL variant is sometimes also known as DiskOnChip 2000 TSOP. From the pdf file that comes with the DOS-based DOC utilities (hint hint): [Inverse NAND Flash Translation Layer] M-Systems' latest flash management algorithm, used by the TrueFFS driver for the following devices: - DiskOnChip Millennium Plus - Mobile DiskOnChip Plus - DiskOnChip 2000 DIP (high), 384Mbytes and higher. - DiskOnChip 2000 DIP (low), 192Mbytes and higher. As for read-only support, its only the bad-block table itself that's read-only, not the device itself. Sorry, I should have been clearer in my message. If more blocks go bad at runtime, the information won't be recorded to flash, and you'll forget about these additional bad blocks at poweroff (which is bad). Unless you're using INFTL filesystem, which has its own markers for post-sale bad blocks. Except INFTL doesn't work with this driver yet. :( The ability to update the BBT is something I plan to add soon, since I need it. :) You should be able to create a filesystem, but as I mentioned I haven't gotten JFFS2 to work for me, yet. > ECC - hardware error correction by the device? Is this an optional > enable in the driver? Yes, the DOC has an ASIC that does ECC computation (for actual error correction, software assitance is required). It's not optional, though it could be made so.... Why would you want to turn it off? > Does it support other filesystems (ext2/3)? Once the (I)NFTL code works with this driver, you can put filesystems like ext2/3 over (I)NFTL. For reasons why you might not want to, read up on JFFS2. > Thanks to everyone working on this. I've needed a driver for doc2000 > dip devices for a couple years now. Yeah, me too, but until now I kept hoping David would do it in his copious spare time :) -Dan