Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932233AbaGHBBN (ORCPT ); Mon, 7 Jul 2014 21:01:13 -0400 Received: from mail-ie0-f173.google.com ([209.85.223.173]:54648 "EHLO mail-ie0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754706AbaGHBBH (ORCPT ); Mon, 7 Jul 2014 21:01:07 -0400 Date: Mon, 7 Jul 2014 19:01:04 -0600 From: Bjorn Helgaas To: Liviu Dudau Cc: linux-pci , 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: Re: [PATCH v8 8/9] pci: Add support for creating a generic host_bridge from device tree Message-ID: <20140708010103.GD22939@google.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <1404240214-9804-9-git-send-email-Liviu.Dudau@arm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 01, 2014 at 07:43:33PM +0100, Liviu Dudau wrote: > 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 | 135 ++++++++++++++++++++++++++++++++++++++++++++++ > drivers/pci/host-bridge.c | 18 +++++++ > include/linux/of_pci.h | 10 ++++ > include/linux/pci.h | 8 +++ > 4 files changed, 171 insertions(+) > > diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c > index 8481996..55d8320 100644 > --- a/drivers/of/of_pci.c > +++ b/drivers/of/of_pci.c > @@ -89,6 +89,141 @@ 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 you're not trying to match other printk formats, you could try to match the %pR format used elsewhere, e.g., "%#010llx-%#010llx" with range.cpu_addr, range.cpu_addr + range.size - 1. > + > + /* > + * 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; > + 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; If you put the dev_info() down here, you can print &bus_range with %pR. > + } > + 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..cfee5d1 100644 > --- a/drivers/pci/host-bridge.c > +++ b/drivers/pci/host-bridge.c > @@ -5,6 +5,9 @@ > #include > #include > #include > +#include > +#include > +#include > > #include "pci.h" > > @@ -83,3 +86,18 @@ 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; > +} I'd wait to add this until there's a platform that needs to implement it. Splitting it out will make this patch that much smaller and easier to understand. > 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 */ I don't see where this is used yet. As far as I know, there's nothing that prevents a host bridge from having several I/O port apertures (or several memory-mapped I/O port spaces). > 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/