From patchwork Sat Mar 3 09:53:24 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 10256047 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 96A9B6037F for ; Sat, 3 Mar 2018 09:55:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 82FDC206E2 for ; Sat, 3 Mar 2018 09:55:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 742792863B; Sat, 3 Mar 2018 09:55:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 9D4CD206E2 for ; Sat, 3 Mar 2018 09:55:05 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 230246E199; Sat, 3 Mar 2018 09:55:04 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mailout2.hostsharing.net (mailout2.hostsharing.net [83.223.90.233]) by gabe.freedesktop.org (Postfix) with ESMTPS id CFBCB6E199; Sat, 3 Mar 2018 09:55:02 +0000 (UTC) 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 E9B3A10189C94; Sat, 3 Mar 2018 10:54:59 +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 DEBD8603E059; Sat, 3 Mar 2018 10:54:58 +0100 (CET) X-Mailbox-Line: From 2962443259e7faec577274b4ef8c54aad66f9a94 Mon Sep 17 00:00:00 2001 Message-Id: <2962443259e7faec577274b4ef8c54aad66f9a94.1520068884.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Sat, 3 Mar 2018 10:53:24 +0100 Subject: [PATCH v2 2/7] PCI: Make pci_wakeup_bus() & pci_bus_set_current_state() public To: dri-devel@lists.freedesktop.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: zigarrre@gmail.com, nouveau@lists.freedesktop.org, Daniel Drake , Denis Lisov , Peter Wu , Martin Lopatar , Alex Deucher , Maik Freudenberg , Raphael Doursenaud MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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: Rafael J. Wysocki Acked-by: Bjorn Helgaas Signed-off-by: Lukas Wunner --- 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 f6a4dd10d9b0..bd6f156dc3cf 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);