From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B77FC2D0A3 for ; Thu, 29 Oct 2020 09:24:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BDB772087E for ; Thu, 29 Oct 2020 09:24:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725948AbgJ2JY6 (ORCPT ); Thu, 29 Oct 2020 05:24:58 -0400 Received: from mga12.intel.com ([192.55.52.136]:63947 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725803AbgJ2JY5 (ORCPT ); Thu, 29 Oct 2020 05:24:57 -0400 IronPort-SDR: 1zFzAifahJMs6YDUyQnW5fmrYYd2o3UsTSXqluptXGuuVvmjhLIa3YOSocdKSSysXoEAbqkkRl pa/6M0dDBE/g== X-IronPort-AV: E=McAfee;i="6000,8403,9788"; a="147684965" X-IronPort-AV: E=Sophos;i="5.77,429,1596524400"; d="scan'208";a="147684965" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Oct 2020 02:24:57 -0700 IronPort-SDR: 1qOSSQvFXfDbo33OAuDktFbq6SQGgfnxx762j56lkbDKoe/1c3hBoGHjSpN5SyCWLgyGR4cjcu iasUSCHIBQcA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,429,1596524400"; d="scan'208";a="536595407" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga005.jf.intel.com with ESMTP; 29 Oct 2020 02:24:54 -0700 Received: by black.fi.intel.com (Postfix, from userid 1001) id 5C0DB4E1; Thu, 29 Oct 2020 11:24:53 +0200 (EET) From: Mika Westerberg To: Bjorn Helgaas , "Rafael J. Wysocki" Cc: Lukas Wunner , David Airlie , Daniel Vetter , Utkarsh Patel , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , linux-pci@vger.kernel.org, Mika Westerberg Subject: [PATCH] PCI/PM: Do not generate wakeup event when runtime resuming bus Date: Thu, 29 Oct 2020 12:24:53 +0300 Message-Id: <20201029092453.69869-1-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org When a PCI bridge is runtime resumed from D3cold the underlying bus is walked and the attached devices are runtime resumed as well. However, in addition to that we also generate a wakeup event for these devices even though this actually is not a real wakeup event coming from the hardware. Normally this does not cause problems but when combined with /sys/power/wakeup_count like using the steps below: # count=$(cat /sys/power/wakeup_count) # echo $count > /sys/power/wakeup_count # echo mem > /sys/power/state The system suspend cycle might get aborted at this point if a PCI bridge that was runtime suspended (D3cold) was runtime resumed for any reason. The runtime resume calls pci_wakeup_bus() and that generates wakeup event increasing wakeup_count. Since this is not a real wakeup event we can prevent the above from happening by removing the call to pci_wakeup_event() in pci_wakeup_bus(). While there rename pci_wakeup_bus() to pci_resume_bus() to better reflect what it does. Reported-by: Utkarsh Patel Signed-off-by: Mika Westerberg --- drivers/gpu/vga/vga_switcheroo.c | 2 +- drivers/pci/pci.c | 16 +++++----------- include/linux/pci.h | 2 +- 3 files changed, 7 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c index 087304b1a5d7..8843b078ad4e 100644 --- a/drivers/gpu/vga/vga_switcheroo.c +++ b/drivers/gpu/vga/vga_switcheroo.c @@ -1039,7 +1039,7 @@ static int vga_switcheroo_runtime_resume(struct device *dev) mutex_lock(&vgasr_mutex); vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_ON); mutex_unlock(&vgasr_mutex); - pci_wakeup_bus(pdev->bus); + pci_resume_bus(pdev->bus); ret = dev->bus->pm->runtime_resume(dev); if (ret) return ret; diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 6d4d5a2f923d..b25dfa63eeb9 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1174,26 +1174,20 @@ int pci_platform_power_transition(struct pci_dev *dev, pci_power_t state) } EXPORT_SYMBOL_GPL(pci_platform_power_transition); -/** - * pci_wakeup - Wake up a PCI device - * @pci_dev: Device to handle. - * @ign: ignored parameter - */ -static int pci_wakeup(struct pci_dev *pci_dev, void *ign) +static int pci_resume_one(struct pci_dev *pci_dev, void *ign) { - pci_wakeup_event(pci_dev); pm_request_resume(&pci_dev->dev); return 0; } /** - * pci_wakeup_bus - Walk given bus and wake up devices on it + * pci_resume_bus - Walk given bus and runtime resume devices on it * @bus: Top bus of the subtree to walk. */ -void pci_wakeup_bus(struct pci_bus *bus) +void pci_resume_bus(struct pci_bus *bus) { if (bus) - pci_walk_bus(bus, pci_wakeup, NULL); + pci_walk_bus(bus, pci_resume_one, NULL); } static int pci_dev_wait(struct pci_dev *dev, char *reset_type, int timeout) @@ -1256,7 +1250,7 @@ int pci_power_up(struct pci_dev *dev) * may be powered on into D0uninitialized state, resume them to * give them a chance to suspend again */ - pci_wakeup_bus(dev->subordinate); + pci_resume_bus(dev->subordinate); } return pci_raw_set_power_state(dev, PCI_D0); diff --git a/include/linux/pci.h b/include/linux/pci.h index 22207a79762c..9256ef2e4327 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1271,7 +1271,7 @@ bool pci_dev_run_wake(struct pci_dev *dev); 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_resume_bus(struct pci_bus *bus); void pci_bus_set_current_state(struct pci_bus *bus, pci_power_t state); /* For use by arch with custom probe code */ -- 2.28.0