Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758931Ab0FCADF (ORCPT ); Wed, 2 Jun 2010 20:03:05 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:45615 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758647Ab0FCADC convert rfc822-to-8bit (ORCPT ); Wed, 2 Jun 2010 20:03:02 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:organization:to:subject:date:user-agent:cc:references :in-reply-to:mime-version:content-type:content-transfer-encoding :message-id; b=jZyyp4M7D9mNa9VTdQ8WEHqcI3iKx3dGilxM8+YZ3UlZEX6Y7san6L9ryP/SHhyAqP fRVRIXiD2Bd6Zt4IKk8srQDUHNtBoFfusVhnswV7p7NRgzxt5oZ8bXLK10fZlNVn50Yn UtC8PX6R9mrsJnYW9PA0kLJJEv6YdvRK+P4qs= From: Marek Vasut Organization: Hack&Dev To: linux-arm-kernel@lists.infradead.org Subject: [URGENT] Re: bit errors on spitz + voipac Date: Thu, 3 Jun 2010 02:01:13 +0200 User-Agent: KMail/1.13.2 (Linux/2.6.33-2-amd64; KDE/4.4.2; x86_64; ; ) Cc: Cyril Hrubis , Stanislav Brabec , Eric Miao , dbaryshkov@gmail.com, arminlitzel@web.de, kernel list , Dirk@opfer-online.de, lenz@cs.wisc.edu, rpurdie@rpsys.net, omegamoon@gmail.com, Pavel Machek , thommycheck@gmail.com, zaurus-devel@www.linuxtogo.org, Haojian Zhuang References: <20100305212708.GC21773@elf.ucw.cz> <1268048916.6477.9.camel@utx.utx.cz> <20100308121634.GA14904@atrey.karlin.mff.cuni.cz> In-Reply-To: <20100308121634.GA14904@atrey.karlin.mff.cuni.cz> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 8BIT Message-Id: <201006030201.13341.marek.vasut@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1388 Lines: 33 Dne Po 8. března 2010 13:16:35 Cyril Hrubis napsal(a): > Hi! > > > - And I see display noise while CF Wi-Fi card is active. > > Forgotten about this one. See for yourself, notice short black vertical > lines flashing randomly. > > http://atrey.karlin.mff.cuni.cz/~metan/outgoing/zaurus_sickness.mpg This is not only case of spitz. I've seen LCD image falling apart on pxafb on Voipac PXA270 board. The image was like "torn in half and part of it was moved to right, the hole between staying white". This happened exactly when I started doing a DMA transfer from a harddrive attached through pata_pxa. It's perfectly replicable. If I disabled DMA and let it run only in PIO, the image was fine. I assume the corruption Pavel was seeing is related. My guess is the problems are caused when DMA between the CPU and a companion chip happens. I dunno if the DMA controller doesn't have enough power to supply LCD and the companion chip with data, but that's one of my guesses. btw. Adjusting the DMA descriptor length in pata_pxa didn't help. Guys, we need to investigate this as it seems to cause problems on many places. Cheers! -- 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/