From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Subhash Jadavani" Subject: RE: DDR eMMC write failures Date: Sun, 13 Nov 2011 22:18:54 +0530 Message-ID: <000901cca224$22f49b40$68ddd1c0$@org> References: <000601cca222$3a103430$ae309c90$@org> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from wolverine02.qualcomm.com ([199.106.114.251]:40795 "EHLO wolverine02.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752829Ab1KMQs5 convert rfc822-to-8bit (ORCPT ); Sun, 13 Nov 2011 11:48:57 -0500 In-Reply-To: <000601cca222$3a103430$ae309c90$@org> Content-Language: en-us Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: 'Praveen Krishnan' , linux-mmc@vger.kernel.org You may also try by lowering the clock speed (from 50mhz to some lower = value say 40 or 30 Mhz). See if you are still seeing the data crc errors with lower clock speed in DDR50 mode or not. Regards, Subhash > -----Original Message----- > From: linux-mmc-owner@vger.kernel.org [mailto:linux-mmc- > owner@vger.kernel.org] On Behalf Of Subhash Jadavani > Sent: Sunday, November 13, 2011 10:05 PM > To: 'Praveen Krishnan'; linux-mmc@vger.kernel.org > Subject: RE: DDR eMMC write failures >=20 > I guess there is some issue with board level signal condition issue o= n > MMC > interface lines. You may try increasing the drive strength of interfa= ce > lines from host controller side. >=20 > Regards, > Subhash >=20 > > -----Original Message----- > > From: linux-mmc-owner@vger.kernel.org [mailto:linux-mmc- > > owner@vger.kernel.org] On Behalf Of Praveen Krishnan > > Sent: Saturday, November 05, 2011 5:57 AM > > To: linux-mmc@vger.kernel.org > > Subject: Re: DDR eMMC write failures > > > > I am seeing some very strange things. > > > > When I do > > > > Dd if=3D/dev/zero of=3D/dev/mmcblk0 bs=3D512k count=3D200 (it fails= when > > writing about 100MB of data with a crc error) > > > > When I do > > Dd if=3D/dev/zero of=3D/dev/mmcblk0 bs=3D64k count=3D3000 (it fails= only > after > > 125 MB of data with a crc error) > > > > When I do > > > > Dd if=3D/dev/zero of=3D/dev/mmcblk0 bs=3D32k count=3D16000 (it fail= s when I > > try to write 500MB of data, but good until 375MB of data) > > > > Any ideas what I am running into? > > > > Thanks, > > Praveen > > > > > > On Wed, Nov 2, 2011 at 4:51 PM, Praveen Krishnan > > > wrote: > > > Hello all, > > > > > > I am working on getting the DDR50 mode up and running for the eMM= C > > > cards. =A0I am running into some weird CRC error cases. =A0Initia= lly, I > > > thought that everything works fine, but when I stress test it wit= h > > > large amounts of data (more than 100MB of writes), I notice that = my > > > console is spewed with venomous error messages. =A0I get a CRC er= ror > > and > > > every now and then, I also see this message "Got data interrupt > even > > > though no data operation was in progress" and "Buffer I/O error" > and > > > so on. > > > > > > Can anybody give any pointers as to what could be causing this? > > > > > > Thanks a lot, > > > Praveen > > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-mmc= " > in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html >=20 > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" = in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html