From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755734Ab0APSCg (ORCPT ); Sat, 16 Jan 2010 13:02:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752594Ab0APSCf (ORCPT ); Sat, 16 Jan 2010 13:02:35 -0500 Received: from khc.piap.pl ([195.187.100.11]:60379 "EHLO khc.piap.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752124Ab0APSCe (ORCPT ); Sat, 16 Jan 2010 13:02:34 -0500 From: Krzysztof Halasa To: Robert Hancock Cc: Jeff Garzik , Seth Heasley , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2.6.32.3] ahci: AHCI and RAID mode SATA patch for Intel Cougar Point DeviceIDs References: <201001121700.18234.seth.heasley@intel.com> <4B4D4EAA.2010109@gmail.com> <4B4DAA68.60608@pobox.com> <4B4DFE1A.4000606@pobox.com> <51f3faa71001131557n52e34260k13bf1fe3057bb0e@mail.gmail.com> <51f3faa71001141615n5776454cwbf6787b7a7fb0081@mail.gmail.com> <51f3faa71001151732s77c198bdu1268879afadd2308@mail.gmail.com> Date: Sat, 16 Jan 2010 19:02:31 +0100 In-Reply-To: <51f3faa71001151732s77c198bdu1268879afadd2308@mail.gmail.com> (Robert Hancock's message of "Fri, 15 Jan 2010 19:32:34 -0600") Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Robert Hancock writes: > Hmm.. From those test results I really suspect some kind of hardware > fault. Could be a defective motherboard - I don't know if that chip > needs any terminating resistors on the motherboard for the SATA signal > lines or something, if so, could be they weren't installed properly.. Unfortunately I can't find a JMB363 datasheet on the net, but there is a certain mb (p965t-a) schematic available. It seems JMB363 doesn't need terminators on SATA RX/TX lines, there is capacitative coupling only (10 nF in each line). The port in question (SATA#2) on my mb (P45 Neo2) uses pins 56 (RXP) 57 (RXN) and 60 (TXN) 61 (TXP). No visible irregularity, the traces look like they should, go straigt to the capacitors, and then to 0R R-packs and to the connector. It looks exactly the same for both ports. There is no short circuit past the capacitors (from the connector side). I'd say quite low probability that there is something wrong with these signals. It seems the chip uses extra 12k resistors for SATA (p965t-a calls the pins SJ_REXT[12]), pin 44 for port#1 and 55 for port#2. Both look sane. I will check the suspected connections with the machine powered off later. The RX and TX trace pairs go next to each other for up to 10 mm, could that be a problem at these frequencies? If so it would show up on all/many such boards certainly? Can't find any report. OTOH other people have similar problems with other boards: e.g. ASUS P5KC: http://ubuntuforums.org/showthread.php?t=766217 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/377633 (unknown boards) https://archlinux-fr.org/doku.php?id=securisation:logcheck http://forum.ubuntu-fr.org/viewtopic.php?pid=2739616 http://ubuntu-ky.ubuntuforums.org/showthread.php?p=7243061 The last one claims: this started after an upgrade to ubuntu 9.04 and is stll here after re-installing ubuntu 8.10. this was fixed by re-installing ubuntu 8.10 only using the kernal, 2.6.27-7-generic. I don't know if JMB36x is involved in this case, and how reliable the info is. Investigating as time permits. -- Krzysztof Halasa