From patchwork Fri Mar 14 15:34:32 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liviu Dudau X-Patchwork-Id: 3833401 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4A2CEBF540 for ; Fri, 14 Mar 2014 15:35:57 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1299F2026C for ; Fri, 14 Mar 2014 15:35:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ED2AB2026D for ; Fri, 14 Mar 2014 15:35:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755579AbaCNPfW (ORCPT ); Fri, 14 Mar 2014 11:35:22 -0400 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21]:51033 "EHLO cam-smtp0.cambridge.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755524AbaCNPfT (ORCPT ); Fri, 14 Mar 2014 11:35:19 -0400 Received: from e106497-lin.cambridge.arm.com (e106497-lin.cambridge.arm.com [10.1.195.170]) by cam-smtp0.cambridge.arm.com (8.13.8/8.13.8) with ESMTP id s2EFYWIE004053; Fri, 14 Mar 2014 15:34:32 GMT From: Liviu Dudau To: linux-pci , Bjorn Helgaas , Catalin Marinas , Will Deacon , Benjamin Herrenschmidt , linaro-kernel , Arnd Bergmann Cc: LKML , "devicetree@vger.kernel.org" , LAKML , Tanmay Inamdar , Grant Likely Subject: [PATCH v7 6/6] pci: Add support for creating a generic host_bridge from device tree Date: Fri, 14 Mar 2014 15:34:32 +0000 Message-Id: <1394811272-1547-7-git-send-email-Liviu.Dudau@arm.com> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1394811272-1547-1-git-send-email-Liviu.Dudau@arm.com> References: <1394811272-1547-1-git-send-email-Liviu.Dudau@arm.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Several platforms use a rather generic version of parsing the device tree to find the host bridge ranges. Move the common code into the generic PCI code and use it to create a pci_host_bridge structure that can be used by arch code. Based on early attempts by Andrew Murray to unify the code. Used powerpc and microblaze PCI code as starting point. Signed-off-by: Liviu Dudau Tested-by: Tanmay Inamdar --- drivers/pci/host-bridge.c | 158 ++++++++++++++++++++++++++++++++++++ include/linux/pci.h | 13 +++ 2 files changed, 171 insertions(+) diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c index 8708b652..7cda90b 100644 --- a/drivers/pci/host-bridge.c +++ b/drivers/pci/host-bridge.c @@ -6,9 +6,14 @@ #include #include #include +#include +#include +#include #include "pci.h" +static atomic_t domain_nr = ATOMIC_INIT(-1); + static struct pci_bus *find_pci_root_bus(struct pci_bus *bus) { while (bus->parent) @@ -92,3 +97,156 @@ void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res, res->end = region->end + offset; } EXPORT_SYMBOL(pcibios_bus_to_resource); + +#ifdef CONFIG_OF +/** + * Simple version of the platform specific code for filtering the list + * of resources obtained from the ranges declaration in DT. + * + * Platforms can override this function in order to impose stronger + * constraints onto the list of resources that a host bridge can use. + * The filtered list will then be used to create a root bus and associate + * it with the host bridge. + * + */ +int __weak pcibios_fixup_bridge_ranges(struct list_head *resources) +{ + return 0; +} + +/** + * pci_host_bridge_of_get_ranges - Parse PCI host bridge resources from DT + * @dev: device node of the host bridge having the range property + * @resources: list where the range of resources will be added after DT parsing + * @io_base: pointer to a variable that will contain the physical address for + * the start of the I/O range. + * + * It is the callers job to free the @resources list if an error is returned. + * + * This function will parse the "ranges" property of a PCI host bridge device + * node and setup the resource mapping based on its content. It is expected + * that the property conforms with the Power ePAPR document. + * + * Each architecture is then offered the chance of applying their own + * filtering of pci_host_bridge_windows based on their own restrictions by + * calling pcibios_fixup_bridge_ranges(). The filtered list of windows + * can then be used when creating a pci_host_bridge structure. + */ +static int pci_host_bridge_of_get_ranges(struct device_node *dev, + struct list_head *resources, resource_size_t *io_base) +{ + struct resource *res; + struct of_pci_range range; + struct of_pci_range_parser parser; + int err; + + pr_info("PCI host bridge %s ranges:\n", dev->full_name); + + /* Check for ranges property */ + err = of_pci_range_parser_init(&parser, dev); + if (err) + return err; + + pr_debug("Parsing ranges property...\n"); + for_each_of_pci_range(&parser, &range) { + /* Read next ranges element */ + pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ", + range.pci_space, range.pci_addr); + pr_debug("cpu_addr:0x%016llx size:0x%016llx\n", + range.cpu_addr, range.size); + + /* + * If we failed translation or got a zero-sized region + * then skip this range + */ + if (range.cpu_addr == OF_BAD_ADDR || range.size == 0) + continue; + + res = kzalloc(sizeof(struct resource), GFP_KERNEL); + if (!res) + return -ENOMEM; + + err = of_pci_range_to_resource(&range, dev, res); + if (err) + return err; + + if (resource_type(res) == IORESOURCE_IO) + *io_base = range.cpu_addr; + + pci_add_resource_offset(resources, res, + res->start - range.pci_addr); + } + + /* Apply architecture specific fixups for the ranges */ + return pcibios_fixup_bridge_ranges(resources); +} + +/** + * of_create_pci_host_bridge - Create a PCI host bridge structure using + * information passed in the DT. + * @parent: device owning this host bridge + * @ops: pci_ops associated with the host controller + * @host_data: opaque data structure used by the host controller. + * + * returns a pointer to the newly created pci_host_bridge structure, or + * NULL if the call failed. + * + * This function will try to obtain the host bridge domain number by + * using of_alias_get_id() call with "pci-domain" as a stem. If that + * fails, a local allocator will be used that will put each host bridge + * in a new domain. + */ +struct pci_host_bridge * +of_create_pci_host_bridge(struct device *parent, struct pci_ops *ops, void *host_data) +{ + int err, domain, busno; + struct resource *bus_range; + struct pci_bus *root_bus; + struct pci_host_bridge *bridge; + resource_size_t io_base; + LIST_HEAD(res); + + bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL); + if (!bus_range) + return ERR_PTR(-ENOMEM); + + domain = of_alias_get_id(parent->of_node, "pci-domain"); + if (domain == -ENODEV) + domain = atomic_inc_return(&domain_nr); + + err = of_pci_parse_bus_range(parent->of_node, bus_range); + if (err) { + dev_info(parent, "No bus range for %s, using default [0-255]\n", + parent->of_node->full_name); + bus_range->start = 0; + bus_range->end = 255; + bus_range->flags = IORESOURCE_BUS; + } + busno = bus_range->start; + pci_add_resource(&res, bus_range); + + /* now parse the rest of host bridge bus ranges */ + err = pci_host_bridge_of_get_ranges(parent->of_node, &res, &io_base); + if (err) + goto err_create; + + /* then create the root bus */ + root_bus = pci_create_root_bus_in_domain(parent, domain, busno, + ops, host_data, &res); + if (IS_ERR(root_bus)) { + err = PTR_ERR(root_bus); + goto err_create; + } + + bridge = to_pci_host_bridge(root_bus->bridge); + bridge->io_base = io_base; + + return bridge; + +err_create: + pci_free_resource_list(&res); + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(of_create_pci_host_bridge); + +#endif /* CONFIG_OF */ diff --git a/include/linux/pci.h b/include/linux/pci.h index 1eed009..40ddd3d 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -395,6 +395,7 @@ struct pci_host_bridge { struct device dev; struct pci_bus *bus; /* root bus */ int domain_nr; + resource_size_t io_base; /* physical address for the start of I/O area */ struct list_head windows; /* pci_host_bridge_windows */ void (*release_fn)(struct pci_host_bridge *); void *release_data; @@ -1786,11 +1787,23 @@ static inline struct device_node *pci_bus_to_OF_node(struct pci_bus *bus) return bus ? bus->dev.of_node : NULL; } +struct pci_host_bridge * +of_create_pci_host_bridge(struct device *parent, struct pci_ops *ops, + void *host_data); + +int pcibios_fixup_bridge_ranges(struct list_head *resources); #else /* CONFIG_OF */ static inline void pci_set_of_node(struct pci_dev *dev) { } static inline void pci_release_of_node(struct pci_dev *dev) { } static inline void pci_set_bus_of_node(struct pci_bus *bus) { } static inline void pci_release_bus_of_node(struct pci_bus *bus) { } + +static inline struct pci_host_bridge * +of_create_pci_host_bridge(struct device *parent, struct pci_ops *ops, + void *host_data) +{ + return NULL; +} #endif /* CONFIG_OF */ #ifdef CONFIG_EEH