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 17BCjS-0003Fw-00 for ; Fri, 24 May 2002 11:55:38 +0100 From: David Woodhouse In-Reply-To: References: To: Chris Wilson Cc: linux-mtd@lists.infradead.org Subject: Re: Getting big flash onto motherboards. Will CF work? what will Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 24 May 2002 11:55:34 +0100 Message-ID: <25366.1022237734@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: chris@netservers.co.uk said: > I would guess that these are IDE-compatible then? So I guess I would > have to use the mtdblock driver to drive it? No. The mtdblock driver is a vary simplistic 'translation layer' that doesn't actually do any wear levelling or translation, just lets you use a real flash device as if it were a block device. If the hardware in question looks like IDE, you use the IDE drivers. > Does it have internal wear levelling like CF? It might. You cannot tell, just like with CF. > Has anyone seen this behaviour, or had any clues about how or why it > might happen? We have had the same effect with several different > brands of CF, including SanDisk. Does this kind of thing happen to > DoC and/or DoM? I have no knowledge of the DiskOnModule. It's just like CF in all respects other than the physical size, isn't it? So there's no real reason to believe that it must have different reliability characteristics. But there's no real reason for _everyone_ who makes CF to have implemented it so unreliably in the first place -- so maybe M-Systems have managed to do it properly -- they generally do seem to have sufficient clue. You'd have to test it. The DiskOnChip is a different matter. That allows the system to deal with real flash, so if there are problems you can fix them. Although in practice, nobody _does_ seem to be dealing with the problems which occasionally crop up with the DiskOnChip drivers. I still keep trying to get our salespeople to find a customer who wants to pay for me to spend some real time on them, but it hasn't happened yet :) -- dwmw2