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
  48 void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
  49                              struct resource *res)
  50 {
  51         struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
  52         struct resource_entry *window;
  53         resource_size_t offset = 0;
  54
  55         resource_list_for_each_entry(window, &bridge->windows) {
  56                 if (resource_contains(window->res, res)) {
  57                         offset = window->offset;
  58                         break;
  59                 }
  60         }
  61
  62         region->start = res->start - offset;
  63         region->end = res->end - offset;
  64 }
  65 EXPORT_SYMBOL(pcibios_resource_to_bus);
  66
  67 static bool region_contains(struct pci_bus_region *region1,
  68                             struct pci_bus_region *region2)
  69 {
  70         return region1->start <= region2->start && region1->end >= region2->end;
  71 }
  72
  73 void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
  74                              struct pci_bus_region *region)
  75 {
  76         struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
  77         struct resource_entry *window;
  78         resource_size_t offset = 0;
  79
  80         resource_list_for_each_entry(window, &bridge->windows) {
  81                 struct pci_bus_region bus_region;
  82
  83                 if (resource_type(res) != resource_type(window->res))
  84                         continue;
  85
  86                 bus_region.start = window->res->start - window->offset;
  87                 bus_region.end = window->res->end - window->offset;
  88
  89                 if (region_contains(&bus_region, region)) {
  90                         offset = window->offset;
  91                         break;
  92                 }
  93         }
  94
  95         res->start = region->start + offset;
  96         res->end = region->end + offset;
  97 }
  98 EXPORT_SYMBOL(pcibios_bus_to_resource);