From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Subject: Re: [PATCH 4/12] PCI PM: Make it possible to force using INTx for PCIe PME signaling Date: Wed, 6 Jan 2010 13:56:25 -0800 Message-ID: <20100106135625.14b37f10@jbarnes-piketon> References: <200912272057.10443.rjw@sisk.pl> <200912272102.22775.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from outbound-mail-319.bluehost.com ([67.222.54.251]:60403 "HELO outbound-mail-319.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S932813Ab0AFV41 (ORCPT ); Wed, 6 Jan 2010 16:56:27 -0500 In-Reply-To: <200912272102.22775.rjw@sisk.pl> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" Cc: Matthew Garrett , Len Brown , LKML , pm list , Alan Stern , ACPI Devel Maling List , Linux PCI , Oliver Neukum , Bjorn Helgaas , Shaohua Li , Francois Romieu On Sun, 27 Dec 2009 21:02:22 +0100 "Rafael J. Wysocki" wrote: > From: Rafael J. Wysocki > > Apparently, some machines may have problems with PCI run-time power > management if MSIs are used for the hative PCIe PME signaling. In > particular, on the MSI Wind U-100 PCIe PME interrupts are not > generated by a PCIe root port after a resume from suspend to RAM, if > the system wake-up was triggered by a PME from the device attached to > this port. [It doesn't help to free the interrupt on suspend and > request it back on resume, even if that is done along with disabling > the MSI and re-enabling it, respectively.] However, if INTx > interrupts are used for this purpose on the same machine, everything > works just fine. > > For this reason, add a kernel command line switch allowing one to > request that MSIs be not used for the native PCIe PME signaling, > introduce a DMI table allowing us to blacklist machines that need > this switch to be set by default and put the MSI Wind U-100 into this > table. > > Signed-off-by: Rafael J. Wysocki > --- This scares me a little... seems like we're not restoring some state on resume that's needed for MSIs to work? Looks fine though. -- Jesse Barnes, Intel Open Source Technology Center