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=-11.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, 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 39887C4320A for ; Fri, 20 Aug 2021 14:47:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2558461057 for ; Fri, 20 Aug 2021 14:47:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240963AbhHTOsR (ORCPT ); Fri, 20 Aug 2021 10:48:17 -0400 Received: from lizzard.sbs.de ([194.138.37.39]:58472 "EHLO lizzard.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240935AbhHTOsQ (ORCPT ); Fri, 20 Aug 2021 10:48:16 -0400 Received: from mail2.sbs.de (mail2.sbs.de [192.129.41.66]) by lizzard.sbs.de (8.15.2/8.15.2) with ESMTPS id 17KElYgX006287 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 20 Aug 2021 16:47:34 +0200 Received: from [167.87.0.29] ([167.87.0.29]) by mail2.sbs.de (8.15.2/8.15.2) with ESMTP id 17KElX7I007803; Fri, 20 Aug 2021 16:47:33 +0200 Subject: Re: [PATCH] PCI/portdrv: Do not setup up IRQs if there are no users To: Lukas Wunner Cc: "linux-pci@vger.kernel.org" , Bjorn Helgaas , Linux Kernel Mailing List References: <43e1591d-51ed-39fa-3bc5-c11777f27b62@siemens.com> <20210820144532.GA25391@wunner.de> From: Jan Kiszka Message-ID: <53a826fb-ece9-450d-e5fc-f145c2513688@siemens.com> Date: Fri, 20 Aug 2021 16:47:33 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <20210820144532.GA25391@wunner.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20.08.21 16:45, Lukas Wunner wrote: > On Fri, Aug 20, 2021 at 03:52:18PM +0200, Jan Kiszka wrote: >> --- a/drivers/pci/pcie/portdrv_core.c >> +++ b/drivers/pci/pcie/portdrv_core.c >> @@ -312,7 +312,7 @@ static int pcie_device_init(struct pci_dev *pdev, int service, int irq) >> */ >> int pcie_port_device_register(struct pci_dev *dev) >> { >> - int status, capabilities, i, nr_service; >> + int status, capabilities, irq_services, i, nr_service; >> int irqs[PCIE_PORT_DEVICE_MAXSERVICES]; >> >> /* Enable PCI Express port device */ >> @@ -326,18 +326,32 @@ int pcie_port_device_register(struct pci_dev *dev) >> return 0; >> >> pci_set_master(dev); >> - /* >> - * Initialize service irqs. Don't use service devices that >> - * require interrupts if there is no way to generate them. >> - * However, some drivers may have a polling mode (e.g. pciehp_poll_mode) >> - * that can be used in the absence of irqs. Allow them to determine >> - * if that is to be used. >> - */ >> - status = pcie_init_service_irqs(dev, irqs, capabilities); >> - if (status) { >> - capabilities &= PCIE_PORT_SERVICE_HP; >> - if (!capabilities) >> - goto error_disable; >> + >> + irq_services = 0; >> + if (IS_ENABLED(CONFIG_PCIE_PME)) >> + irq_services |= PCIE_PORT_SERVICE_PME; >> + if (IS_ENABLED(CONFIG_PCIEAER)) >> + irq_services |= PCIE_PORT_SERVICE_AER; >> + if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE)) >> + irq_services |= PCIE_PORT_SERVICE_HP; >> + if (IS_ENABLED(CONFIG_PCIE_DPC)) >> + irq_services |= PCIE_PORT_SERVICE_DPC; >> + irq_services &= capabilities; > > get_port_device_capability() would seem like a more natural place > to put these checks. > > Note that your check for CONFIG_PCIEAER is superfluous due to > the "#ifdef CONFIG_PCIEAER" in get_port_device_capability(). > Not all service drivers need IRQs. That's why the test is separate. See also the comment I shuffled around. Jan -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux