From patchwork Wed Apr 26 11:17:54 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Pieralisi X-Patchwork-Id: 9701145 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 4A11E603F6 for ; Wed, 26 Apr 2017 11:17:51 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4602B2807B for ; Wed, 26 Apr 2017 11:17:51 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3A74528437; Wed, 26 Apr 2017 11:17:51 +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 CE0D92807B for ; Wed, 26 Apr 2017 11:17:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2999256AbdDZLRt (ORCPT ); Wed, 26 Apr 2017 07:17:49 -0400 Received: from foss.arm.com ([217.140.101.70]:53932 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2999245AbdDZLRq (ORCPT ); Wed, 26 Apr 2017 07:17:46 -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 BED60169E; Wed, 26 Apr 2017 04:17:44 -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 CE6BA3F3E1; Wed, 26 Apr 2017 04:17:40 -0700 (PDT) From: Lorenzo Pieralisi To: linux-pci@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Lorenzo Pieralisi , Arnd Bergmann , Bjorn Helgaas , Will Deacon , Russell King , Pratyush Anand , Jingoo Han , Rob Herring , Simon Horman , Mingkai Hu , Tanmay Inamdar , Murali Karicheri , Bharat Kumar Gogada , Wenrui Li , Shawn Lin , Minghuan Lian , Gabriele Paoloni , Thomas Petazzoni , Joao Pinto , Thierry Reding , Michal Simek , Stanimir Varbanov , Zhou Wang , Roy Zang , Matthew Minter Subject: [RFC/RFT PATCH 03/18] PCI: Introduce pci_scan_root_bus_bridge() Date: Wed, 26 Apr 2017 12:17:54 +0100 Message-Id: <20170426111809.19922-4-lorenzo.pieralisi@arm.com> X-Mailer: git-send-email 2.10.0 In-Reply-To: <20170426111809.19922-1-lorenzo.pieralisi@arm.com> References: <20170426111809.19922-1-lorenzo.pieralisi@arm.com> 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 Current pci_scan_root_bus() interface is made up of two main code paths: - pci_create_root_bus() - pci_scan_child_bus() pci_create_root_bus() is a wrapper function that allows to create a struct pci_host_bridge structure, initialize it with the passed parameters and register it with the kernel. As the struct pci_host_bridge require additional struct members, pci_create_root_bus() parameters list has grown in time, making it unwieldy to add further parameters to it in case the struct pci_host_bridge gains more members fields to augment its functionality. Since PCI core code provides functions to allocate struct pci_host_bridge, instead of forcing the pci_create_root_bus() interface to add new parameters to cater for new struct pci_host_bridge functionality, it is more suitable to add an interface in PCI core code to scan a PCI bus straight from a struct pci_host_bridge created and customized by each specific PCI host controller driver. Add a pci_scan_root_bus_bridge() function to allow PCI host controller drivers to create and initialize struct pci_host_bridge and scan the resulting bus. Signed-off-by: Lorenzo Pieralisi Cc: Arnd Bergmann Cc: Bjorn Helgaas --- drivers/pci/probe.c | 38 ++++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 1 + 2 files changed, 39 insertions(+) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 7e4ffc4..c7a7f72 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2412,6 +2412,44 @@ void pci_bus_release_busn_res(struct pci_bus *b) res, ret ? "can not be" : "is"); } +int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge) +{ + struct resource_entry *window; + bool found = false; + struct pci_bus *b; + int max, bus, ret; + + if (!bridge) + return -EINVAL; + + resource_list_for_each_entry(window, &bridge->windows) + if (window->res->flags & IORESOURCE_BUS) { + found = true; + break; + } + + ret = pci_register_host_bridge(bridge); + if (ret < 0) + return ret; + + b = bridge->bus; + bus = bridge->busnr; + + if (!found) { + dev_info(&b->dev, + "No busn resource found for root bus, will use [bus %02x-ff]\n", + bus); + pci_bus_insert_busn_res(b, bus, 255); + } + + max = pci_scan_child_bus(b); + + if (!found) + pci_bus_update_busn_res_end(b, max); + + return 0; +} + struct pci_bus *pci_scan_root_bus_msi(struct device *parent, int bus, struct pci_ops *ops, void *sysdata, struct list_head *resources, struct msi_controller *msi) diff --git a/include/linux/pci.h b/include/linux/pci.h index 99878a9..757779a 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -847,6 +847,7 @@ struct pci_bus *pci_scan_root_bus_msi(struct device *parent, int bus, struct pci_bus *pci_scan_root_bus(struct device *parent, int bus, struct pci_ops *ops, void *sysdata, struct list_head *resources); +int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge); struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr); void pcie_update_link_speed(struct pci_bus *bus, u16 link_status);