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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 7C0C8C4320A for ; Mon, 9 Aug 2021 09:47:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 649026023B for ; Mon, 9 Aug 2021 09:47:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234724AbhHIJrz (ORCPT ); Mon, 9 Aug 2021 05:47:55 -0400 Received: from bmailout2.hostsharing.net ([83.223.78.240]:45819 "EHLO bmailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234365AbhHIJrz (ORCPT ); Mon, 9 Aug 2021 05:47:55 -0400 Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "RapidSSL TLS DV RSA Mixed SHA256 2020 CA-1" (verified OK)) by bmailout2.hostsharing.net (Postfix) with ESMTPS id 2F86F2800B3D2; Mon, 9 Aug 2021 11:47:31 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 1733A260B31; Mon, 9 Aug 2021 11:47:31 +0200 (CEST) Date: Mon, 9 Aug 2021 11:47:31 +0200 From: Lukas Wunner To: Kai-Heng Feng Cc: bhelgaas@google.com, Sean V Kelley , Jonathan Cameron , Qiuxu Zhuo , Kuppuswamy Sathyanarayanan , Keith Busch , "open list:PCI SUBSYSTEM" , open list , Mika Westerberg Subject: Re: [PATCH] PCI/portdrv: Disallow runtime suspend when waekup is required but PME service isn't supported Message-ID: <20210809094731.GA16595@wunner.de> References: <20210713075726.1232938-1-kai.heng.feng@canonical.com> <20210809042414.107430-1-kai.heng.feng@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210809042414.107430-1-kai.heng.feng@canonical.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [cc += Mika] On Mon, Aug 09, 2021 at 12:24:12PM +0800, Kai-Heng Feng wrote: > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=213873 The last comment on this bugzilla says "BIOS will fix this." and the status is RESOLVED WILL_NOT_FIX. Why is the patch still necessary? > Some platforms cannot detect ethernet hotplug once its upstream port is > runtime suspended because PME isn't enabled in _OSC. If PME is not handled natively, why does the NIC runtime suspend? Shouldn't this be fixed in the NIC driver by keeping the device runtime active if PME cannot be used? > Disallow port runtime suspend when any child device requires wakeup, so > pci_pme_list_scan() can still read the PME status from the devices > behind the port. pci_pme_list_scan() is for broken devices which fail to signal PME. Is this NIC really among them or does PME fail merely because it's not granted to OSPM? > --- a/drivers/pci/pcie/portdrv_pci.c > +++ b/drivers/pci/pcie/portdrv_pci.c > @@ -59,14 +59,30 @@ static int pcie_port_runtime_suspend(struct device *dev) > return pcie_port_device_runtime_suspend(dev); > } > > +static int pcie_port_wakeup_check(struct device *dev, void *data) > +{ > + struct pci_dev *pdev = to_pci_dev(dev); > + > + if (!pdev) > + return 0; > + > + return pdev->wakeup_prepared; > +} > + > static int pcie_port_runtime_idle(struct device *dev) > { > + struct pci_dev *pdev = to_pci_dev(dev); > + > + if (!pcie_port_find_device(pdev, PCIE_PORT_SERVICE_PME) && > + device_for_each_child(dev, NULL, pcie_port_wakeup_check)) > + return -EBUSY; > + > /* > * Assume the PCI core has set bridge_d3 whenever it thinks the port > * should be good to go to D3. Everything else, including moving > * the port to D3, is handled by the PCI core. > */ > - return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY; > + return pdev->bridge_d3 ? 0 : -EBUSY; If an additional check is necessary for this issue, it should be integrated into pci_dev_check_d3cold() instead of pcie_port_runtime_idle(). Thanks, Lukas