Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753852Ab0G1DkU (ORCPT ); Tue, 27 Jul 2010 23:40:20 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:49081 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753330Ab0G1DkS (ORCPT ); Tue, 27 Jul 2010 23:40:18 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Message-ID: <4C4FA663.9090204@jp.fujitsu.com> Date: Wed, 28 Jul 2010 12:39:15 +0900 From: Hidetoshi Seto User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; ja; rv:1.9.2.7) Gecko/20100713 Thunderbird/3.1.1 MIME-Version: 1.0 To: "Rafael J. Wysocki" CC: linux-pci@vger.kernel.org, Len Brown , ACPI Devel Maling List , linux-pm@lists.linux-foundation.org, Linux Kernel Mailing List , Matthew Garrett , Jesse Barnes Subject: Re: [RFC][PATCH] PCI / PCIe: Ask BIOS for control of all native services simultaneously References: <201007250105.23610.rjw@sisk.pl> In-Reply-To: <201007250105.23610.rjw@sisk.pl> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1321 Lines: 38 Hi, (2010/07/25 8:05), Rafael J. Wysocki wrote: > It turns out that asking ACPI BIOS, through _OSC, for control of each > PCIe port native service individually sometimes confuses the BIOS if > one sevice is requested while the others are not (eg. requesting > control of the native PCIe PME without requesting control of the > native PCIe hot-plug at the same time leads to interrupt storms on > some systems). Then why not invent quirks or something for such systems? IMHO it sounds like a BIOS bug since it should grant PME control to OS only when both of PME and pciehp (plus PCIe caps) are requested at same time. Did you confirm that the system also confuses when pciehp is requested without requesting PME? e.g. assume that some BIOS might behave: _OSC(pciehp) => OK _OSC(PME) => NG (bugs on shared interrupt?) _OSC(pciehp|PME) => OK _OSC(SHPC) => OK _OSC(pciehp|SHPC) => NG (must choose one, not both) _OSC(AER|SHPC) => OK I don't doubt that handling of _OSC needs some improvement... Thanks, H.Seto -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/