drivers/pci/host-bridge.c

   1 /*
   2  * host bridge related code
   3  */
   4
   5 #include <linux/kernel.h>
   6 #include <linux/pci.h>
   7 #include <linux/module.h>
   8
   9 #include "pci.h"
  10
  11 static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
  12 {
  13         while (bus->parent)
  14                 bus = bus->parent;
  15
  16         return bus;
  17 }
  18
  19 struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus)
  20 {
  21         struct pci_bus *root_bus = find_pci_root_bus(bus);
  22
  23         return to_pci_host_bridge(root_bus->bridge);
  24 }
  25
  26 struct device *pci_get_host_bridge_device(struct pci_dev *dev)
  27 {
  28         struct pci_bus *root_bus = find_pci_root_bus(dev->bus);
  29         struct device *bridge = root_bus->bridge;
  30
  31         kobject_get(&bridge->kobj);
  32         return bridge;
  33 }
  34
  35 void  pci_put_host_bridge_device(struct device *dev)
  36 {
  37         kobject_put(&dev->kobj);
  38 }
  39
  40 void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
  41                                  void (*release_fn)(struct pci_host_bridge *),
  42                                  void *release_data)
  43 {
  44         bridge->release_fn = release_fn;
  45         bridge->release_data = release_data;
  46 }
  47 EXPORT_SYMBOL_GPL(pci_set_host_bridge_release);
  48
  49 void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
  50                              struct resource *res)
  51 {
  52         struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
  53         struct resource_entry *window;
  54         resource_size_t offset = 0;
  55
  56         resource_list_for_each_entry(window, &bridge->windows) {
  57                 if (resource_contains(window->res, res)) {
  58                         offset = window->offset;
  59                         break;
  60                 }
  61         }
  62
  63         region->start = res->start - offset;
  64         region->end = res->end - offset;
  65 }
  66 EXPORT_SYMBOL(pcibios_resource_to_bus);
  67
  68 static bool region_contains(struct pci_bus_region *region1,
  69                             struct pci_bus_region *region2)
  70 {
  71         return region1->start <= region2->start && region1->end >= region2->end;
  72 }
  73
  74 void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
  75                              struct pci_bus_region *region)
  76 {
  77         struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
  78         struct resource_entry *window;
  79         resource_size_t offset = 0;
  80
  81         resource_list_for_each_entry(window, &bridge->windows) {
  82                 struct pci_bus_region bus_region;
  83
  84                 if (resource_type(res) != resource_type(window->res))
  85                         continue;
  86
  87                 bus_region.start = window->res->start - window->offset;
  88                 bus_region.end = window->res->end - window->offset;
  89
  90                 if (region_contains(&bus_region, region)) {
  91                         offset = window->offset;
  92                         break;
  93                 }
  94         }
  95
  96         res->start = region->start + offset;
  97         res->end = region->end + offset;
  98 }
  99 EXPORT_SYMBOL(pcibios_bus_to_resource);