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 17sQ7u-0007tL-00 for ; Fri, 20 Sep 2002 16:55:30 +0100 From: David Woodhouse In-Reply-To: References: To: "Jack Lu" Cc: linux-mtd@lists.infradead.org Subject: Re: about jffs2's compression and cfi->fast_prog being turn off Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 20 Sep 2002 16:55:26 +0100 Message-ID: <22326.1032537326@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: jlu@rdmcorp.com said: > 1. With this latest jffs2, can we turn off the compression? If can , > how can we turn it? Not implemented yet. Send patch -- it's quite simple :) > 2. If we still use the jffs2 compression after we compress the image > using CCITT4 Group algorithm, could it help us to reduce the size to > store the compressed image into the flash memory? It's unlikely that further compression will have any useful effect. You could try telling it to attempt only 'rtime' compression, but just telling it not to compress the file(s) in question would be best. > 3. With the latest jffs2, the erase suspend is implemented for AMD > CFI chips, such as Am29Lv320MB? JFFS2 knows nothing of such things. The current cfi_cmdset_0002 code does not support erase suspend. I've never had hardware I can test on, and nobody's submitted a patch known to be working. Again, fairly simple to implement this yourself. > Turnning off the cfi->fast_prog will affect the the time needed to > program the flahsh? It shouldn't make a lot of difference. -- dwmw2