From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933101Ab0CKPkV (ORCPT ); Thu, 11 Mar 2010 10:40:21 -0500 Received: from ns.penguin.cz ([84.21.108.25]:49491 "EHLO ns.penguin.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932198Ab0CKPkT (ORCPT ); Thu, 11 Mar 2010 10:40:19 -0500 Subject: Re: bit errors on spitz From: Stanislav Brabec To: Andy Green Cc: Cyril Hrubis , Pavel Machek , Eric Miao , dbaryshkov@gmail.com, arminlitzel@web.de, kernel list , Dirk@opfer-online.de, lenz@cs.wisc.edu, rpurdie@rpsys.net, omegamoon@gmail.com, thommycheck@gmail.com, zaurus-devel@www.linuxtogo.org, linux-arm-kernel In-Reply-To: <4B98EF5D.5000609@warmcat.com> References: <20100305212708.GC21773@elf.ucw.cz> <20100308072858.GA29939@atrey.karlin.mff.cuni.cz> <20100308082530.GA1982@atrey.karlin.mff.cuni.cz> <4B98EF5D.5000609@warmcat.com> Content-Type: text/plain; charset="ISO-8859-2" Date: Thu, 11 Mar 2010 16:42:35 +0100 Message-ID: <1268322155.3990.114.camel@hammer.suse.cz> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Andy Green wrote: > I saw very similar failures for a long time on our iMX31 based device. > Eventually I found a Freescale errata where the RAM inside the USB2 > macrocell started to make single bit errors below 1.38V Vcore; ours was > 1.4V at that time but dipped on CPU load. Good tip. It seems that nobody ported driver for the voltage control chip ISL6271 from 2.4 kernel, and bootloader probably does not set correct values. Datasheet: http://www.penguin.cz/~utx/zaurus/datasheets/power/Xscale/ISL6271.pdf -- Stanislav Brabec http://www.penguin.cz/~utx/zaurus