From patchwork Sun Feb 18 08:38:32 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 874851 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zkgKp3LFgz9ryf for ; Sun, 18 Feb 2018 19:39:42 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751187AbeBRIjk (ORCPT ); Sun, 18 Feb 2018 03:39:40 -0500 Received: from mailout2.hostsharing.net ([83.223.90.233]:36527 "EHLO mailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751052AbeBRIjj (ORCPT ); Sun, 18 Feb 2018 03:39:39 -0500 Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "COMODO RSA Domain Validation Secure Server CA" (not verified)) by mailout2.hostsharing.net (Postfix) with ESMTPS id 2ED671008C2D1; Sun, 18 Feb 2018 09:39:37 +0100 (CET) Received: from localhost (6-38-90-81.adsl.cmo.de [81.90.38.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id 3494B603E059; Sun, 18 Feb 2018 09:39:36 +0100 (CET) X-Mailbox-Line: From 9d36522bc3d7e0ed1c1d5f653514d9fb0d34c0a8 Mon Sep 17 00:00:00 2001 Message-Id: <9d36522bc3d7e0ed1c1d5f653514d9fb0d34c0a8.1518941073.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Sun, 18 Feb 2018 09:38:32 +0100 Subject: [PATCH 2/7] PCI: Make pci_wakeup_bus() & pci_bus_set_current_state() public To: dri-devel@lists.freedesktop.org Cc: Peter Wu , Alex Deucher , Dave Airlie , nouveau@lists.freedesktop.org, Ben Skeggs , Lyude Paul , Hans de Goede , alsa-devel@alsa-project.org, Takashi Iwai , Jaroslav Kysela , linux-pm@vger.kernel.org, "Rafael J. Wysocki" , Pierre Moreau , Bastien Nocera , Bjorn Helgaas , linux-pci@vger.kernel.org Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org There are PCI devices which are power-manageable by a nonstandard means, such as a custom ACPI method. One example are discrete GPUs in hybrid graphics laptops, another are Thunderbolt controllers in Macs. Such devices can't be put into D3cold with pci_set_power_state() because pci_platform_power_transition() fails with -ENODEV. Instead they're put into D3hot by pci_set_power_state() and subsequently into D3cold by invoking the nonstandard means. However as a consequence the cached current_state is incorrectly left at D3hot. What we need to do is walk the hierarchy below such a PCI device on powerdown and update the current_state to D3cold. On powerup the PCI device itself and the hierarchy below it is in D0uninitialized, so we need to walk the hierarchy again and wake all devices, causing them to be put into D0active and then letting them autosuspend as they see fit. To this end make pci_wakeup_bus() & pci_bus_set_current_state() public so PCI drivers don't have to reinvent the wheel. Cc: Bjorn Helgaas Cc: Rafael J. Wysocki Signed-off-by: Lukas Wunner Acked-by: Bjorn Helgaas --- drivers/pci/pci.c | 8 ++++---- include/linux/pci.h | 2 ++ 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index f694650235f2..6e6e322a5a7d 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -800,7 +800,7 @@ static int pci_wakeup(struct pci_dev *pci_dev, void *ign) * pci_wakeup_bus - Walk given bus and wake up devices on it * @bus: Top bus of the subtree to walk. */ -static void pci_wakeup_bus(struct pci_bus *bus) +void pci_wakeup_bus(struct pci_bus *bus) { if (bus) pci_walk_bus(bus, pci_wakeup, NULL); @@ -850,11 +850,11 @@ static int __pci_dev_set_current_state(struct pci_dev *dev, void *data) } /** - * __pci_bus_set_current_state - Walk given bus and set current state of devices + * pci_bus_set_current_state - Walk given bus and set current state of devices * @bus: Top bus of the subtree to walk. * @state: state to be set */ -static void __pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state) +void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state) { if (bus) pci_walk_bus(bus, __pci_dev_set_current_state, &state); @@ -876,7 +876,7 @@ int __pci_complete_power_transition(struct pci_dev *dev, pci_power_t state) ret = pci_platform_power_transition(dev, state); /* Power off the bridge may power off the whole hierarchy */ if (!ret && state == PCI_D3cold) - __pci_bus_set_current_state(dev->subordinate, PCI_D3cold); + pci_bus_set_current_state(dev->subordinate, PCI_D3cold); return ret; } EXPORT_SYMBOL_GPL(__pci_complete_power_transition); diff --git a/include/linux/pci.h b/include/linux/pci.h index 024a1beda008..ae42289662df 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1147,6 +1147,8 @@ void pci_pme_wakeup_bus(struct pci_bus *bus); void pci_d3cold_enable(struct pci_dev *dev); void pci_d3cold_disable(struct pci_dev *dev); bool pcie_relaxed_ordering_enabled(struct pci_dev *dev); +void pci_wakeup_bus(struct pci_bus *bus); +void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state); /* PCI Virtual Channel */ int pci_save_vc_state(struct pci_dev *dev);