From patchwork Thu Dec 3 22:40:13 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Machek X-Patchwork-Id: 7763941 Return-Path: X-Original-To: patchwork-linux-acpi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 14B0D9F1C2 for ; Thu, 3 Dec 2015 22:40:21 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 491292046F for ; Thu, 3 Dec 2015 22:40:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A4CD20456 for ; Thu, 3 Dec 2015 22:40:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751260AbbLCWkS (ORCPT ); Thu, 3 Dec 2015 17:40:18 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:38099 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751243AbbLCWkQ (ORCPT ); Thu, 3 Dec 2015 17:40:16 -0500 Received: by atrey.karlin.mff.cuni.cz (Postfix, from userid 512) id C60DE82248; Thu, 3 Dec 2015 23:40:14 +0100 (CET) Date: Thu, 3 Dec 2015 23:40:13 +0100 From: Pavel Machek To: Josef Bacik Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, bhelgaas@google.com, shli@fb.com, kernel-team@fb.com Subject: Re: [PATCH] pci: completely disable aspm if it's unsupported Message-ID: <20151203224013.GG14427@amd> References: <1447856703-2566-1-git-send-email-jbacik@fb.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1447856703-2566-1-git-send-email-jbacik@fb.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hi! > We have some hardware that takes about 30 seconds to setup common clocks for > ASPM, but our bios'es don't actually allow ASPM. It seems we had this thing in > place where we would disable ASPM after the pci bus probe so that we would make > sure that pre pcie 1.1 devices would be properly skipped during initialization. > This is because the mechanism to disable ASPM doesn't actually disable the > setting up of the link state stuff, it just keeps us from changing the link > state after the fact. So instead make it so that when we call pcie_no_aspm() > that we disable ASPM completley, that is we skip setting up the link state and > everything. This way we avoid the costly setup for a feature we cannot support > in the first place and we also make sure we are safe from future tampering with > the ASPM link state. Thanks, On thinkpad x60, I have similar problem. I'm carying this for long long time now: diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index a32ba75..5eb7621 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -700,7 +700,7 @@ static int __init acpi_pci_init(void) if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) { pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n"); - pcie_no_aspm(); +// pcie_no_aspm(); } ret = register_acpi_bus_type(&acpi_pci_bus);