Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755047AbbGTSW5 (ORCPT ); Mon, 20 Jul 2015 14:22:57 -0400 Received: from mail-wg0-f52.google.com ([74.125.82.52]:35264 "EHLO mail-wg0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753024AbbGTSWy convert rfc822-to-8bit (ORCPT ); Mon, 20 Jul 2015 14:22:54 -0400 MIME-Version: 1.0 In-Reply-To: <20150720180847.GH24125@google.com> References: <1431356341-31640-1-git-send-email-antoine.tenart@free-electrons.com> <1431356341-31640-8-git-send-email-antoine.tenart@free-electrons.com> <555792FC.8030407@vanguardiasur.com.ar> <20150520140631.GN22054@kwain> <555C9584.1030609@vanguardiasur.com.ar> <20150520142409.GP22054@kwain> <20150520144341.GQ22054@kwain> <55621B83.4040909@vanguardiasur.com.ar> <20150720180847.GH24125@google.com> Date: Mon, 20 Jul 2015 15:22:53 -0300 Message-ID: Subject: Re: [PATCH v5 07/12] mtd: nand: add Samsung K9GBG08U0A-M to nand_ids table From: Ezequiel Garcia To: Brian Norris Cc: Antoine Tenart , Sebastian Hesselbarth , David Woodhouse , Boris Brezillon , zmxu@marvell.com, jszhang@marvell.com, linux-arm-kernel , "linux-mtd@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Robert Jarzmik Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2319 Lines: 64 On 20 July 2015 at 15:08, Brian Norris wrote: > Hi Ezequiel, > > On Sun, May 24, 2015 at 03:42:11PM -0300, Ezequiel Garcia wrote: >> On 05/20/2015 11:43 AM, Antoine Tenart wrote: >> [..] >> >> >> >> I just had a look on the datasheet, and I you're right, the nand should >> >> support JDEC. However I get a "No NAND device found" error when >> >> reverting this patch. >> >> >> >> It seems nand_flash_detect_jedec() is not reading "JDEC" and is returning >> >> directly. I'm having a look at this. >> > >> > So, I can read 'J', 'E', 'D' and 'E' but then I got 0xff's. So I tried >> > to only check of JEDE in nand_flash_detect_jedec() but the JEDEC >> > parameter page was then not valid. >> > >> >> This uncovers two different bugs in the driver. >> >> 1. read_id_bytes is either '2' or '4', but JEDEC detections needs at >> least 5 bytes. >> >> 2. The initial buffer (to read the ID and the parameter page) has >> 256 bytes, but the JEDEC parameter page is 512-bytes. >> >> And while at it, the driver doesn't seem to support reading the >> redundant parameter pages (recently reported on barebox ML [1]). So this >> is a third bug. >> >> Would you try setting read_id_bytes to '5' and also increasing the READ_PARAM >> transfer length? Something like this: > > I'm trying to parse through the latest pxa3xx_nand patches, and I'm a > bit lost. Did this piece get dropped on the floor? > As far as I can see, yes. Regarding this particular patch, the flash device supports JEDEC detection but the driver needs a fix. Hopefully, Antoine will submit a fix in the future. > At any rate, it looks like there are a few more things to fix in > Antoine's latest work, so I can't quite take them. Correct me if I'm > misunderstanding. > The current patchset under discussion is "v2 mtd: pxa3xx_nand: rework the timing setup": http://lists.infradead.org/pipermail/linux-mtd/2015-July/060033.html We are trying to get that sorted out, so we can move to the Berlin SoC support. Cheers, -- Ezequiel García, VanguardiaSur www.vanguardiasur.com.ar -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/