From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751692AbWDCJVv (ORCPT ); Mon, 3 Apr 2006 05:21:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751693AbWDCJVv (ORCPT ); Mon, 3 Apr 2006 05:21:51 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:58586 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S1751692AbWDCJVu (ORCPT ); Mon, 3 Apr 2006 05:21:50 -0400 Subject: Re: [RESEND][2.6.15] New ATA error messages on upgrade to 2.6.15 From: Alan Cox To: Mikael Pettersson Cc: mrmacman_g4@mac.com, edmudama@gmail.com, hahn@physics.mcmaster.ca, hancockr@shaw.ca, jujutama@comcast.net, linux-kernel@vger.kernel.org In-Reply-To: <200604030907.k33974O9020701@harpo.it.uu.se> References: <200604030907.k33974O9020701@harpo.it.uu.se> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Mon, 03 Apr 2006 10:29:36 +0100 Message-Id: <1144056576.719.16.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Llu, 2006-04-03 at 11:07 +0200, Mikael Pettersson wrote: > 20269 PCI controller card. The 20269+cable+disk does udma5 > just fine in a PC, but throws a few BadCRCs at bootup on > the PowerMac, resets and drops to udma4, and then things work > OK for me, but I don't stress it very much (no RAID). Interesting. > Since the card's bios doesn't get run at powerup, I always > suspected that the driver fails to initialize some timing thing. The BIOS does various bits of PCI bus setup on some systems including latency setting. That might be relevant, especially latency to get bursting. > Another possibility is the "data coherency" issue in some > G4 CPUs which requires mappings of memory shared with other > agents to use some additional magic in the page table. The CRC is computed between the controller as the bits get fired over the cable and drive so it shouldn't be caused by any weird bus timings. More info would be useful although it may be a while before I can look at it