From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from qw-out-2122.google.com (qw-out-2122.google.com [74.125.92.25]) by ozlabs.org (Postfix) with ESMTP id EFAF0DE2CE for ; Fri, 17 Apr 2009 07:28:02 +1000 (EST) Received: by qw-out-2122.google.com with SMTP id 9so584678qwb.15 for ; Thu, 16 Apr 2009 14:28:00 -0700 (PDT) MIME-Version: 1.0 Sender: timur.tabi@gmail.com In-Reply-To: <49DD8871.2030404@garzik.org> References: <49DB6914.1030107@freescale.com> <49DD11D1.7060105@freescale.com> <49DD1375.8030400@kernel.org> <49DD1465.6070001@freescale.com> <49DD17C3.7040607@kernel.org> <1239234793.6214.5.camel@localhost> <1239251928.22777.2.camel@localhost> <49DD8871.2030404@garzik.org> Date: Thu, 16 Apr 2009 16:27:59 -0500 Message-ID: Subject: Re: "ahci: drop intx manipulation on msi enable" breaks ULI M1575 From: Timur Tabi To: Jeff Garzik Content-Type: text/plain; charset=ISO-8859-1 Cc: Tejun Heo , Linux PPC Development , linux-ide@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thu, Apr 9, 2009 at 12:32 AM, Jeff Garzik wrote: > 3) As a result, Timur's 'ahci' is no longer receiving interrupts. Presuma= bly > this means that BOTH of the following conditions are true > > =A0 =A0 =A0 =A0a) INTX is disabled > =A0 =A0 =A0 =A0b) MSI is not available > > Today I am thinking we should either revert the libata commit > (a5bfc4714b3f01365aef89a92673f2ceb1ccf246), or poke PCI to twiddle INTX f= or > us at pci_enable_device() time, perhaps. We (Freescale) have discussed and debugged this issue, and I'm 99% certain that we have a board-specific fix, so there's no need to revert the patch. According to the original developer, he had to disable the INTX on the board if SATA were disabled, otherwise some other problem occurred. He noticed that the interrupt was re-enabled (presumably by the pre-patch code in ahci.c), so he thought it would be okay to disable it. I've run some tests, and so far it appears that the problem does not occur with the latest kernel (or the latest revision of the hardware). I need to run some more tests to be absolutely certain. If those tests pass, then I will post a patch that modifies hpcd_quirk_uli5288(). So please, don't revert any patches. And thanks to everyone for helping me resolve this issue. --=20 Timur Tabi Linux kernel developer at Freescale