From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from risingsoftware01.propagation.net ([66.221.33.65]) by bombadil.infradead.org with esmtps (Exim 4.68 #1 (Red Hat Linux)) id 1JovTB-0006sh-Pc for linux-mtd@lists.infradead.org; Thu, 24 Apr 2008 07:02:14 +0000 Date: Thu, 24 Apr 2008 17:02:06 +1000 From: Hamish Moffatt To: Artem Bityutskiy Subject: Re: [RFC] slight UBI scan time improvement Message-ID: <20080424070206.GA20799@cloud.net.au> References: <1208882552.11721.13.camel@sauron> <20080423073840.GA9472@cloud.net.au> <480EEFAB.7010304@parrot.com> <1208938864.11721.44.camel@sauron> <20080423124046.GA16201@cloud.net.au> <1208955467.11721.69.camel@sauron> <20080423134254.GA17867@cloud.net.au> <1208959759.11721.76.camel@sauron> <20080424015303.GB13358@cloud.net.au> <1209018080.11721.88.camel@sauron> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1209018080.11721.88.camel@sauron> Cc: linux-mtd@lists.infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, Apr 24, 2008 at 09:21:20AM +0300, Artem Bityutskiy wrote: > On Thu, 2008-04-24 at 11:53 +1000, Hamish Moffatt wrote: > > Hmm. The software ECC seems to work internally on 256 byte blocks. > > However it appears that nand_base will always read in a whole page (2K > > on my flash). It should be ok to read only a 256-byte block as that's > > all you need for ECC calculation? Not a whole 2K which requires 8 ECC > > calculations. > > However, there was a patch from Alexey which may certainly help you. It > was not looked at properly, unfortunately. I'll try to find it in my > mailbox and will send to you. Thanks. Yes I found the patch in my linux-mtd folder too. It's very nice! Here's my attach time before: [ 0.950000] NAND device: Manufacturer ID: 0xec, Chip ID: 0xdc (Samsung NAND 512MiB 3,3V 8-bit) [ 0.960000] Scanning device for bad blocks [ 1.000000] Bad eraseblock 494 at 0x03dc0000 [ 1.050000] Bad eraseblock 1300 at 0x0a280000 [ 1.140000] Bad eraseblock 2554 at 0x13f40000 [ 1.160000] Bad eraseblock 2923 at 0x16d60000 [ 1.200000] Bad eraseblock 3349 at 0x1a2a0000 [ 1.230000] Bad eraseblock 3790 at 0x1d9c0000 [ 6.900000] UBI: attached mtd9 to ubi0 ... and now: [ 0.950000] NAND device: Manufacturer ID: 0xec, Chip ID: 0xdc (Samsung NAND 512MiB 3,3V 8-bit) [ 0.970000] Scanning device for bad blocks [ 1.000000] Bad eraseblock 494 at 0x03dc0000 [ 1.060000] Bad eraseblock 1300 at 0x0a280000 [ 1.140000] Bad eraseblock 2554 at 0x13f40000 [ 1.170000] Bad eraseblock 2923 at 0x16d60000 [ 1.200000] Bad eraseblock 3349 at 0x1a2a0000 [ 1.230000] Bad eraseblock 3790 at 0x1d9c0000 [ 3.880000] UBI: attached mtd9 to ubi0 Hamish -- Hamish Moffatt VK3SB