From patchwork Thu Sep 28 11:37:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Pieralisi X-Patchwork-Id: 9975853 X-Patchwork-Delegate: bhelgaas@google.com 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 9AF9B6037E for ; Thu, 28 Sep 2017 11:34:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 834DF294DD for ; Thu, 28 Sep 2017 11:34:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 763D12954C; Thu, 28 Sep 2017 11:34:39 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5AAE4294E5 for ; Thu, 28 Sep 2017 11:34:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751888AbdI1Leg (ORCPT ); Thu, 28 Sep 2017 07:34:36 -0400 Received: from foss.arm.com ([217.140.101.70]:55544 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751082AbdI1Leg (ORCPT ); Thu, 28 Sep 2017 07:34:36 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 92C0F1529; Thu, 28 Sep 2017 04:34:35 -0700 (PDT) Received: from red-moon.cambridge.arm.com (red-moon.cambridge.arm.com [10.1.206.55]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A29BE3F53D; Thu, 28 Sep 2017 04:34:33 -0700 (PDT) From: Lorenzo Pieralisi To: linux-pci@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ide@vger.kernel.org, Lorenzo Pieralisi , Bjorn Helgaas , Richard Henderson , Ivan Kokshaysky , "David S. Miller" , Guenter Roeck , Matt Turner Subject: [PATCH] PCI: Fix legacy IRQ assignment execution stage Date: Thu, 28 Sep 2017 12:37:07 +0100 Message-Id: <1506598627-8985-1-git-send-email-lorenzo.pieralisi@arm.com> X-Mailer: git-send-email 2.4.12 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Through struct pci_host_bridge->{map/swizzle}_irq() hooks is now possible to define IRQ mapping functions on a per PCI host bridge basis. Actual IRQ allocation is carried out by the pci_assign_irq() function in pci_device_probe() - to make sure a device is assigned an IRQ only if it is probed (ie match a driver); it retrieves a struct pci_host_bridge* for a given PCI device and through {map/swizzle}_irq() hooks it carries out the PCI IRQ allocation. As it turned out, some legacy drivers (eg IDE layer) require that a device allocates IRQ as soon as it is added so that its actual IRQ settings are available early in the boot process. With current code calling pci_assign_irq() in pci_device_probe() IDE IRQ probing fails for some drivers: ide0: disabled, no IRQ ide0: failed to initialize IDE interface ide0: disabling port cmd64x 0000:00:02.0: IDE controller (0x1095:0x0646 rev 0x07) CMD64x_IDE 0000:00:02.0: BAR 0: can't reserve [io 0x8050-0x8057] cmd64x 0000:00:02.0: can't reserve resources CMD64x_IDE: probe of 0000:00:02.0 failed with error -16 ide_generic: please use "probe_mask=0x3f" module parameter for probing all legacy ISA IDE ports ------------[ cut here ]------------ WARNING: CPU: 0 PID: 1 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x94/0xd0 sysfs: cannot create duplicate filename '/class/ide_port/ide0' ... Trace: [] __warn+0x160/0x190 [] sysfs_warn_dup+0x94/0xd0 [] warn_slowpath_fmt+0x58/0x70 [] sysfs_warn_dup+0x94/0xd0 [] kernfs_path_from_node+0x30/0x60 [] kernfs_put+0x16c/0x2c0 [] kernfs_put+0x16c/0x2c0 [] sysfs_do_create_link_sd.isra.2+0x100/0x120 [] device_add+0x2a4/0x7c0 [] device_create_groups_vargs+0x14c/0x170 [] device_create_groups_vargs+0x98/0x170 [] device_create+0x50/0x70 [] ide_host_register+0x48c/0xa00 [] ide_host_register+0x450/0xa00 [] device_register+0x20/0x50 [] ide_host_register+0x450/0xa00 [] ide_host_add+0x64/0xe0 [] kobject_uevent_env+0x16c/0x710 [] do_one_initcall+0x68/0x260 [] kernel_init+0x1c/0x1a0 [] kernel_init+0x0/0x1a0 [] ret_from_kernel_thread+0x18/0x20 [] kernel_init+0x0/0x1a0 ---[ end trace 24a70433c3e4d374 ]--- ide0: disabling port Fix the IRQ allocation issue by moving the pci_assign_irq() call from pci_device_probe() to pci_device_add(), so that IRQs for a given PCI device are allocated as soon as it is scanned by the PCI enumeration. This has the drawback of allocating an IRQ even for PCI devices that do not have a matching kernel driver but it should be safe to carry out in all configurations. Fixes: 30fdfb929e82 ("PCI: Add a call to pci_assign_irq() in pci_device_probe()") Link: http://lkml.kernel.org/r/32ec730f-c1b0-5584-cd35-f8a809122b96@roeck-us.net Signed-off-by: Lorenzo Pieralisi Reported-by: Guenter Roeck Cc: Bjorn Helgaas Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: David S. Miller Cc: Guenter Roeck Cc: Matt Turner Tested-by: Guenter Roeck --- drivers/pci/pci-driver.c | 2 -- drivers/pci/probe.c | 3 +++ 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 11bd267..750d688 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -415,8 +415,6 @@ static int pci_device_probe(struct device *dev) struct pci_dev *pci_dev = to_pci_dev(dev); struct pci_driver *drv = to_pci_driver(dev->driver); - pci_assign_irq(pci_dev); - error = pcibios_alloc_irq(pci_dev); if (error < 0) return error; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index ff94b69..ba4e466 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2103,6 +2103,9 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) /* Initialize various capabilities */ pci_init_capabilities(dev); + /* Assign device IRQ number */ + pci_assign_irq(dev); + /* * Add the device to our list of discovered devices * and the bus list for fixup functions, etc.