From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: Enabling MSI in sata_nv Date: Mon, 03 Dec 2007 14:16:15 -0500 Message-ID: <475455FF.2060707@garzik.org> References: <47537304.2030801@overt.org> <87f94c370712031055h4c359ee9w59fd076fedcc8b9f@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:53440 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751384AbXLCTQS (ORCPT ); Mon, 3 Dec 2007 14:16:18 -0500 In-Reply-To: <87f94c370712031055h4c359ee9w59fd076fedcc8b9f@mail.gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Philip Langdale Cc: Greg Freemyer , linux-ide@vger.kernel.org, Mark Lord Greg Freemyer wrote: > On Dec 2, 2007 10:07 PM, Philip Langdale wrote: >> Hi all, >> >> At least for my hardware (MCP55), the sata controller supports MSI >> and it seems that turning it on is as simple as inserting the call >> to pci_enable_msi - after that it Just Works(tm). >> >> Are there any gotchas that I'm missing? Would a patch to do this >> be accepted? >> >> --phil > > I don't know if it is relevant, but I had to disable MSI to get a > MCP55 NIC to work under 2.6.22. MSI is pretty flaky, but we default it to 'on' for AHCI, which is the "enhanced mode" side of the sata_nv chip. So it is likely that it works on newer boards -- but even though Mark Lord's response was mistaken (he thought sata_mv was being discussed), he was right too... sata_nv has stability problems and I would prefer not to enable MSI just yet, until we cure the other problems. Jeff