diff options
Diffstat (limited to 'drivers/of/of_pci.c')
| -rw-r--r-- | drivers/of/of_pci.c | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c new file mode 100644 index 000000000..5751dc5b6 --- /dev/null +++ b/drivers/of/of_pci.c @@ -0,0 +1,301 @@ +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of_pci.h> +#include <linux/slab.h> + +static inline int __of_pci_pci_compare(struct device_node *node, + unsigned int data) +{ + int devfn; + + devfn = of_pci_get_devfn(node); + if (devfn < 0) + return 0; + + return devfn == data; +} + +struct device_node *of_pci_find_child_device(struct device_node *parent, + unsigned int devfn) +{ + struct device_node *node, *node2; + + for_each_child_of_node(parent, node) { + if (__of_pci_pci_compare(node, devfn)) + return node; + /* + * Some OFs create a parent node "multifunc-device" as + * a fake root for all functions of a multi-function + * device we go down them as well. + */ + if (!strcmp(node->name, "multifunc-device")) { + for_each_child_of_node(node, node2) { + if (__of_pci_pci_compare(node2, devfn)) { + of_node_put(node); + return node2; + } + } + } + } + return NULL; +} +EXPORT_SYMBOL_GPL(of_pci_find_child_device); + +/** + * of_pci_get_devfn() - Get device and function numbers for a device node + * @np: device node + * + * Parses a standard 5-cell PCI resource and returns an 8-bit value that can + * be passed to the PCI_SLOT() and PCI_FUNC() macros to extract the device + * and function numbers respectively. On error a negative error code is + * returned. + */ +int of_pci_get_devfn(struct device_node *np) +{ + unsigned int size; + const __be32 *reg; + + reg = of_get_property(np, "reg", &size); + + if (!reg || size < 5 * sizeof(__be32)) + return -EINVAL; + + return (be32_to_cpup(reg) >> 8) & 0xff; +} +EXPORT_SYMBOL_GPL(of_pci_get_devfn); + +/** + * of_pci_parse_bus_range() - parse the bus-range property of a PCI device + * @node: device node + * @res: address to a struct resource to return the bus-range + * + * Returns 0 on success or a negative error-code on failure. + */ +int of_pci_parse_bus_range(struct device_node *node, struct resource *res) +{ + const __be32 *values; + int len; + + values = of_get_property(node, "bus-range", &len); + if (!values || len < sizeof(*values) * 2) + return -EINVAL; + + res->name = node->name; + res->start = be32_to_cpup(values++); + res->end = be32_to_cpup(values); + res->flags = IORESOURCE_BUS; + + return 0; +} +EXPORT_SYMBOL_GPL(of_pci_parse_bus_range); + +/** + * This function will try to obtain the host bridge domain number by + * finding a property called "linux,pci-domain" of the given device node. + * + * @node: device tree node with the domain information + * + * Returns the associated domain number from DT in the range [0-0xffff], or + * a negative value if the required property is not found. + */ +int of_get_pci_domain_nr(struct device_node *node) +{ + const __be32 *value; + int len; + u16 domain; + + value = of_get_property(node, "linux,pci-domain", &len); + if (!value || len < sizeof(*value)) + return -EINVAL; + + domain = (u16)be32_to_cpup(value); + + return domain; +} +EXPORT_SYMBOL_GPL(of_get_pci_domain_nr); + +/** + * of_pci_dma_configure - Setup DMA configuration + * @dev: ptr to pci_dev struct of the PCI device + * + * Function to update PCI devices's DMA configuration using the same + * info from the OF node of host bridge's parent (if any). + */ +void of_pci_dma_configure(struct pci_dev *pci_dev) +{ + struct device *dev = &pci_dev->dev; + struct device *bridge = pci_get_host_bridge_device(pci_dev); + + if (!bridge->parent) + return; + + of_dma_configure(dev, bridge->parent->of_node); + pci_put_host_bridge_device(bridge); +} +EXPORT_SYMBOL_GPL(of_pci_dma_configure); + +#if defined(CONFIG_OF_ADDRESS) +/** + * of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT + * @dev: device node of the host bridge having the range property + * @busno: bus number associated with the bridge root bus + * @bus_max: maximum number of buses for this bridge + * @resources: list where the range of resources will be added after DT parsing + * @io_base: pointer to a variable that will contain on return the physical + * address for the start of the I/O range. Can be NULL if the caller doesn't + * expect IO ranges to be present in the device tree. + * + * It is the caller's job to free the @resources list. + * + * 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. + * + * It returns zero if the range parsing has been successful or a standard error + * value if it failed. + */ +int of_pci_get_host_bridge_resources(struct device_node *dev, + unsigned char busno, unsigned char bus_max, + struct list_head *resources, resource_size_t *io_base) +{ + struct resource_entry *window; + struct resource *res; + struct resource *bus_range; + struct of_pci_range range; + struct of_pci_range_parser parser; + char range_type[4]; + int err; + + if (io_base) + *io_base = (resource_size_t)OF_BAD_ADDR; + + bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL); + if (!bus_range) + return -ENOMEM; + + pr_info("PCI host bridge %s ranges:\n", dev->full_name); + + err = of_pci_parse_bus_range(dev, bus_range); + if (err) { + bus_range->start = busno; + bus_range->end = bus_max; + bus_range->flags = IORESOURCE_BUS; + pr_info(" No bus range found for %s, using %pR\n", + dev->full_name, bus_range); + } else { + if (bus_range->end > bus_range->start + bus_max) + bus_range->end = bus_range->start + bus_max; + } + pci_add_resource(resources, bus_range); + + /* Check for ranges property */ + err = of_pci_range_parser_init(&parser, dev); + if (err) + goto parse_failed; + + pr_debug("Parsing ranges property...\n"); + for_each_of_pci_range(&parser, &range) { + /* Read next ranges element */ + if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO) + snprintf(range_type, 4, " IO"); + else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM) + snprintf(range_type, 4, "MEM"); + else + snprintf(range_type, 4, "err"); + pr_info(" %s %#010llx..%#010llx -> %#010llx\n", range_type, + range.cpu_addr, range.cpu_addr + range.size - 1, + range.pci_addr); + + /* + * 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) { + err = -ENOMEM; + goto parse_failed; + } + + err = of_pci_range_to_resource(&range, dev, res); + if (err) + goto conversion_failed; + + if (resource_type(res) == IORESOURCE_IO) { + if (!io_base) { + pr_err("I/O range found for %s. Please provide an io_base pointer to save CPU base address\n", + dev->full_name); + err = -EINVAL; + goto conversion_failed; + } + if (*io_base != (resource_size_t)OF_BAD_ADDR) + pr_warn("More than one I/O resource converted for %s. CPU base address for old range lost!\n", + dev->full_name); + *io_base = range.cpu_addr; + } + + pci_add_resource_offset(resources, res, res->start - range.pci_addr); + } + + return 0; + +conversion_failed: + kfree(res); +parse_failed: + resource_list_for_each_entry(window, resources) + kfree(window->res); + pci_free_resource_list(resources); + return err; +} +EXPORT_SYMBOL_GPL(of_pci_get_host_bridge_resources); +#endif /* CONFIG_OF_ADDRESS */ + +#ifdef CONFIG_PCI_MSI + +static LIST_HEAD(of_pci_msi_chip_list); +static DEFINE_MUTEX(of_pci_msi_chip_mutex); + +int of_pci_msi_chip_add(struct msi_controller *chip) +{ + if (!of_property_read_bool(chip->of_node, "msi-controller")) + return -EINVAL; + + mutex_lock(&of_pci_msi_chip_mutex); + list_add(&chip->list, &of_pci_msi_chip_list); + mutex_unlock(&of_pci_msi_chip_mutex); + + return 0; +} +EXPORT_SYMBOL_GPL(of_pci_msi_chip_add); + +void of_pci_msi_chip_remove(struct msi_controller *chip) +{ + mutex_lock(&of_pci_msi_chip_mutex); + list_del(&chip->list); + mutex_unlock(&of_pci_msi_chip_mutex); +} +EXPORT_SYMBOL_GPL(of_pci_msi_chip_remove); + +struct msi_controller *of_pci_find_msi_chip_by_node(struct device_node *of_node) +{ + struct msi_controller *c; + + mutex_lock(&of_pci_msi_chip_mutex); + list_for_each_entry(c, &of_pci_msi_chip_list, list) { + if (c->of_node == of_node) { + mutex_unlock(&of_pci_msi_chip_mutex); + return c; + } + } + mutex_unlock(&of_pci_msi_chip_mutex); + + return NULL; +} +EXPORT_SYMBOL_GPL(of_pci_find_msi_chip_by_node); + +#endif /* CONFIG_PCI_MSI */ |