Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752283AbaGAUvn (ORCPT ); Tue, 1 Jul 2014 16:51:43 -0400 Received: from dliviu.plus.com ([80.229.23.120]:32838 "EHLO smtp.dudau.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751654AbaGAUvm (ORCPT ); Tue, 1 Jul 2014 16:51:42 -0400 From: "Liviu Dudau" Date: Tue, 1 Jul 2014 21:50:50 +0100 To: Liviu Dudau Cc: linux-pci , Bjorn Helgaas , Catalin Marinas , Will Deacon , Benjamin Herrenschmidt , Arnd Bergmann , linaro-kernel , Tanmay Inamdar , Grant Likely , Sinan Kaya , Jingoo Han , Kukjin Kim , Suravee Suthikulanit , LKML , Device Tree ML , LAKML Subject: [RESEND] [PATCH v8 8/9] pci: Add support for creating a generic host_bridge from device tree Message-ID: <20140701205050.GB19569@bart.dudau.co.uk> References: <1404240214-9804-1-git-send-email-Liviu.Dudau@arm.com> <1404240214-9804-9-git-send-email-Liviu.Dudau@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1404240214-9804-9-git-send-email-Liviu.Dudau@arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-DSPAM-Result: Whitelisted X-DSPAM-Processed: Tue Jul 1 21:51:39 2014 X-DSPAM-Confidence: 0.9899 X-DSPAM-Probability: 0.0000 X-DSPAM-Signature: 13,53b31f5b3301702818276 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 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/of/of_pci.c | 136 ++++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/host-bridge.c | 15 +++++ include/linux/of_pci.h | 10 ++++ include/linux/pci.h | 8 +++ 4 files changed, 169 insertions(+) diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 8481996..e81402a 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -1,6 +1,7 @@ #include #include #include +#include #include static inline int __of_pci_pci_compare(struct device_node *node, @@ -89,6 +90,141 @@ int of_pci_parse_bus_range(struct device_node *node, struct resource *res) } EXPORT_SYMBOL_GPL(of_pci_parse_bus_range); +/** + * 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 cpu_addr:0x%016llx size:0x%016llx\n", + range.pci_space, range.pci_addr, 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); +} + +static atomic_t domain_nr = ATOMIC_INIT(-1); + +/** + * 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 = 0; + 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); + #ifdef CONFIG_PCI_MSI static LIST_HEAD(of_pci_msi_chip_list); diff --git a/drivers/pci/host-bridge.c b/drivers/pci/host-bridge.c index 36c669e..54ceafd 100644 --- a/drivers/pci/host-bridge.c +++ b/drivers/pci/host-bridge.c @@ -83,3 +83,18 @@ void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res, res->end = region->end + offset; } EXPORT_SYMBOL(pcibios_bus_to_resource); + +/** + * 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; +} diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index dde3a4a..71e36d0 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -15,6 +15,9 @@ struct device_node *of_pci_find_child_device(struct device_node *parent, int of_pci_get_devfn(struct device_node *np); int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); +struct pci_host_bridge *of_create_pci_host_bridge(struct device *parent, + struct pci_ops *ops, void *host_data); + #else static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) { @@ -43,6 +46,13 @@ of_pci_parse_bus_range(struct device_node *node, struct resource *res) { return -EINVAL; } + +static inline struct pci_host_bridge * +of_create_pci_host_bridge(struct device *parent, struct pci_ops *ops, + void *host_data) +{ + return NULL; +} #endif #if defined(CONFIG_OF) && defined(CONFIG_PCI_MSI) diff --git a/include/linux/pci.h b/include/linux/pci.h index 7e7b939..556dc5f 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -402,6 +402,7 @@ 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; @@ -1809,8 +1810,15 @@ 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) { } + #endif /* CONFIG_OF */ +/* Used by architecture code to apply any quirks to the list of + * pci_host_bridge resource ranges before they are being used + * by of_create_pci_host_bridge() + */ +extern int pcibios_fixup_bridge_ranges(struct list_head *resources); + #ifdef CONFIG_EEH static inline struct eeh_dev *pci_dev_to_eeh_dev(struct pci_dev *pdev) { -- 2.0.0 -- 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/