From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner+w=401wt.eu-S932927Ab0AFV43@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S932927Ab0AFV43 (ORCPT <rfc822;w@1wt.eu>);
	Wed, 6 Jan 2010 16:56:29 -0500
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932904Ab0AFV41
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Wed, 6 Jan 2010 16:56:27 -0500
Received: from outbound-mail-319.bluehost.com ([67.222.54.251]:54159 "HELO
	outbound-mail-319.bluehost.com" rhost-flags-OK-OK-OK-OK)
	by vger.kernel.org with SMTP id S932783Ab0AFV41 (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 6 Jan 2010 16:56:27 -0500
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=default; d=virtuousgeek.org;
	h=Received:Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References:X-Mailer:Mime-Version:Content-Type:Content-Transfer-Encoding:X-Identified-User;
	b=S40Nys366igAp0yMT/MbnGZwZoXY25N/qykrpkQakm3qGexuJjwfbiFcAHTzAISfjQzSBD8kmPxI+n/sEAfvEWaLB4sJ8slj4Msu/CNLqr/rFi2kOQUALBRjlzFCaiWX;
Date: Wed, 6 Jan 2010 13:56:25 -0800
From: Jesse Barnes <jbarnes@virtuousgeek.org>
To: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Matthew Garrett <mjg@redhat.com>, Len Brown <lenb@kernel.org>,
       LKML <linux-kernel@vger.kernel.org>,
       pm list <linux-pm@lists.linux-foundation.org>,
       Alan Stern <stern@rowland.harvard.edu>,
       ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
       Linux PCI <linux-pci@vger.kernel.org>,
       Oliver Neukum <oliver@neukum.org>, Bjorn Helgaas <bjorn.helgaas@hp.com>,
       Shaohua Li <shaohua.li@intel.com>,
       Francois Romieu <romieu@fr.zoreil.com>
Subject: Re: [PATCH 4/12] PCI PM: Make it possible to force using INTx for
 PCIe PME signaling
Message-ID: <20100106135625.14b37f10@jbarnes-piketon>
In-Reply-To: <200912272102.22775.rjw@sisk.pl>
References: <200912272057.10443.rjw@sisk.pl>
	<200912272102.22775.rjw@sisk.pl>
X-Mailer: Claws Mail 3.7.2 (GTK+ 2.18.3; x86_64-pc-linux-gnu)
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
X-Identified-User: {10642:box514.bluehost.com:virtuous:virtuousgeek.org} {sentby:smtp auth 75.111.28.251 authed with jbarnes@virtuousgeek.org}
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Sun, 27 Dec 2009 21:02:22 +0100
"Rafael J. Wysocki" <rjw@sisk.pl> wrote:

> From: Rafael J. Wysocki <rjw@sisk.pl>
> 
> 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 <rjw@sisk.pl>
> ---

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