Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753372AbaBCSfX (ORCPT ); Mon, 3 Feb 2014 13:35:23 -0500 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21]:54710 "EHLO cam-smtp0.cambridge.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751912AbaBCSfT (ORCPT ); Mon, 3 Feb 2014 13:35:19 -0500 From: Liviu Dudau To: linux-pci , Bjorn Helgaas , Catalin Marinas , Will Deacon Cc: LKML , "devicetree@vger.kernel.org" , LAKML , linaro-kernel Subject: [PATCH] pci: Add support for creating a generic host_bridge from device tree Date: Mon, 3 Feb 2014 18:33:48 +0000 Message-Id: <1391452428-22917-2-git-send-email-Liviu.Dudau@arm.com> X-Mailer: git-send-email 1.8.5.3 In-Reply-To: <1391452428-22917-1-git-send-email-Liviu.Dudau@arm.com> References: <1391452428-22917-1-git-send-email-Liviu.Dudau@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Several platforms use a rather generic version of parsing the device tree to find the host bridge ranges. Move that 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 Cc: Catalin Marinas Cc: Will Deacon --- drivers/pci/host-bridge.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/probe.c | 11 ++++++ include/linux/pci.h | 14 ++++++++ 3 files changed, 117 insertions(+) diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c index 06ace62..9d11deb 100644 --- a/drivers/pci/host-bridge.c +++ b/drivers/pci/host-bridge.c @@ -6,6 +6,7 @@ #include #include #include +#include #include "pci.h" @@ -91,3 +92,94 @@ void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res, res->end = region->end + offset; } EXPORT_SYMBOL(pcibios_bus_to_resource); + +/** + * 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 + * + * 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 will then apply their filtering based on the limitations + * of each platform. One general restriction seems to be the number of IO space + * ranges, the PCI framework makes intensive use of struct resource management, + * and for IORESOURCE_IO types they can only be requested if they are contained + * within the global ioport_resource, so that should be limited to one IO space + * range. + */ +static int pci_host_bridge_of_get_ranges(struct device_node *dev, + struct list_head *resources) +{ + 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 + * (some FW try to feed us with non sensical zero sized regions + * such as power3 which look like some kind of attempt + * at exposing the VGA memory hole) then skip this range + */ + if (range.cpu_addr == OF_BAD_ADDR || range.size == 0) + continue; + + res = kzalloc(sizeof(struct resource), GFP_KERNEL); + if (!res) { + err = -ENOMEM; + goto bridge_ranges_nomem; + } + + of_pci_range_to_resource(&range, dev, res); + + pci_add_resource_offset(resources, res, + range.cpu_addr - range.pci_addr); + } + + /* Apply architecture specific fixups for the ranges */ + pcibios_fixup_bridge_ranges(resources); + + return 0; + +bridge_ranges_nomem: + pci_free_resource_list(resources); + return err; +} + +struct pci_host_bridge * +pci_host_bridge_of_init(struct device *parent, int busno, struct pci_ops *ops, + void *host_data, struct list_head *resources) +{ + struct pci_bus *root_bus; + struct pci_host_bridge *bridge; + + /* first parse the host bridge bus ranges */ + if (pci_host_bridge_of_get_ranges(parent->of_node, resources)) + return NULL; + + /* then create the root bus */ + root_bus = pci_create_root_bus(parent, busno, ops, host_data, resources); + if (!root_bus) + return NULL; + + bridge = to_pci_host_bridge(root_bus->bridge); + + return bridge; +} +EXPORT_SYMBOL(pci_host_bridge_of_init); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 6e34498..16febae 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1787,6 +1787,17 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, list_for_each_entry_safe(window, n, resources, list) { list_move_tail(&window->list, &bridge->windows); res = window->res; + /* + * IO resources are stored in the kernel with a CPU start + * address of zero. Adjust the data accordingly and remember + * the offset + */ + if (resource_type(res) == IORESOURCE_IO) { + bridge->io_offset = res->start; + res->end -= res->start; + window->offset -= res->start; + res->start = 0; + } offset = window->offset; if (res->flags & IORESOURCE_BUS) pci_bus_insert_busn_res(b, bus, res->end); diff --git a/include/linux/pci.h b/include/linux/pci.h index fb57c89..8953997 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -394,6 +394,8 @@ struct pci_host_bridge_window { struct pci_host_bridge { struct device dev; struct pci_bus *bus; /* root bus */ + resource_size_t io_offset; /* CPU address offset for io resources */ + int domain_nr; struct list_head windows; /* pci_host_bridge_windows */ void (*release_fn)(struct pci_host_bridge *); void *release_data; @@ -1762,11 +1764,23 @@ 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 * +pci_host_bridge_of_init(struct device *parent, int busno, struct pci_ops *ops, + void *host_data, struct list_head *resources); + +void 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 * +pci_host_bridge_of_init(struct device *parent, struct pci_ops *ops, + void *host_data, struct list_head *resources) +{ + return NULL; +} #endif /* CONFIG_OF */ #ifdef CONFIG_EEH -- 1.8.5.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/