From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pa0-f47.google.com ([209.85.220.47]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1U1Wmv-00028m-Rz for linux-mtd@lists.infradead.org; Sat, 02 Feb 2013 06:41:23 +0000 Received: by mail-pa0-f47.google.com with SMTP id bj3so1419185pad.34 for ; Fri, 01 Feb 2013 22:41:20 -0800 (PST) Message-ID: <510CB507.4020105@gmail.com> Date: Sat, 02 Feb 2013 12:11:11 +0530 From: Vikram Narayanan MIME-Version: 1.0 To: Huang Shijie Subject: Re: mtd_oobtest fails with GPMI-NAND References: <50F97DB5.7040801@gmail.com> <50FCA426.6030309@freescale.com> <5105E4CE.1090800@gmail.com> <5105EE9B.9050405@freescale.com> <5106AFAA.1020502@gmail.com> <51072EA4.7000201@freescale.com> <51073373.4080006@gmail.com> <510735B3.1040509@freescale.com> <5107F899.5090506@gmail.com> <5108852C.5040002@freescale.com> In-Reply-To: <5108852C.5040002@freescale.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Cc: linux-mtd@lists.infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 1/30/2013 7:57 AM, Huang Shijie wrote: > 于 2013年01月30日 00:28, Vikram Narayanan 写道: >> On 1/29/2013 8:06 AM, Huang Shijie wrote: >>>> May I know in what way the driver is restricted for using with other >>>> boards? >>> The devicetree. Please check the dts file in arch/arm/boot/dts/. >>> If there is no dts file for your board, the gpmi will not works very >>> well for your board. >>> for example, there is arch/arm/boot/dts/imx6q-arm2.dts for the MX6Q-ARM2 >>> board. >> >> I've a valid dts file for my board which is good enough to probe the >> Toshiba NAND on-board and mount a UBIFS filesystem. > could you tell the dts file for your board? > are you sure the pinmux settings are right? I'm using the same pinumx settings mentioned in the file "arch/arm/boot/dts/imx6q.dtsi". Hope that is right. >> >>>> You're right and we knew it earlier as the Kernel detects the OOB size >>>> as 128 bytes. So, some remaining bytes become unused at the end of >>>> each page. i.e., (224-128). Instead of supporting ecc strength as ECC9 >>>> we end up using ECC8. Should this be a cause for the -74 error? >>> no. this is not the cause. even you get the wrong geometry of the nand >>> chip. the gpmi still can works. >>> >>> I think the root cause is the devicetree issue as above. >> >> Something else is causing the issue. Can you give some other pointers >> which can potentially cause this -74 error while mounting? > the -74 error is the EBADMSG, it's caused by the uncorrectable ECC failure. > There are many reasons can cause this error: > [1] the pinmux setting is not right, the gpmi does not works well. As said above, my pinmux settings are right. GPMI detects my NAND, does read/write/erase/mount. At times I'm seeing this -74 issue. Sometimes this error goes off in the next reboot. > [2] the wrong setting of BCH. for example, the page size is 8K, you > set 4k to BCH. > so you can set the correct nand geometry parameters for your > nand chip firstly, and then do the debug. From the driver I understood that the geometry are determined according to the data from the read_id bytes. mtd layer detects my NAND as 4K page-sized. So, this shouldn't be a problem I guess. > [3] timings. Should I tweak something specific according to the NAND device that I have? Can you give more hints please? Thanks, Vikram