drivers/pci/host-bridge.c

   1 /*
   2  * host bridge related code
   3  */
   4
   5 #include <linux/kernel.h>
   6 #include <linux/init.h>
   7 #include <linux/pci.h>
   8 #include <linux/module.h>
   9
  10 #include "pci.h"
  11
  12 static struct pci_bus *find_pci_root_bus(struct pci_dev *dev)
  13 {
  14         struct pci_bus *bus;
  15
  16         bus = dev->bus;
  17         while (bus->parent)
  18                 bus = bus->parent;
  19
  20         return bus;
  21 }
  22
  23 static struct pci_host_bridge *find_pci_host_bridge(struct pci_dev *dev)
  24 {
  25         struct pci_bus *bus = find_pci_root_bus(dev);
  26
  27         return to_pci_host_bridge(bus->bridge);
  28 }
  29
  30 void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
  31                                  void (*release_fn)(struct pci_host_bridge *),
  32                                  void *release_data)
  33 {
  34         bridge->release_fn = release_fn;
  35         bridge->release_data = release_data;
  36 }
  37
  38 static bool resource_contains(struct resource *res1, struct resource *res2)
  39 {
  40         return res1->start <= res2->start && res1->end >= res2->end;
  41 }
  42
  43 void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
  44                              struct resource *res)
  45 {
  46         struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
  47         struct pci_host_bridge_window *window;
  48         resource_size_t offset = 0;
  49
  50         list_for_each_entry(window, &bridge->windows, list) {
  51                 if (resource_type(res) != resource_type(window->res))
  52                         continue;
  53
  54                 if (resource_contains(window->res, res)) {
  55                         offset = window->offset;
  56                         break;
  57                 }
  58         }
  59
  60         region->start = res->start - offset;
  61         region->end = res->end - offset;
  62 }
  63 EXPORT_SYMBOL(pcibios_resource_to_bus);
  64
  65 static bool region_contains(struct pci_bus_region *region1,
  66                             struct pci_bus_region *region2)
  67 {
  68         return region1->start <= region2->start && region1->end >= region2->end;
  69 }
  70
  71 void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
  72                              struct pci_bus_region *region)
  73 {
  74         struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
  75         struct pci_host_bridge_window *window;
  76         resource_size_t offset = 0;
  77
  78         list_for_each_entry(window, &bridge->windows, list) {
  79                 struct pci_bus_region bus_region;
  80
  81                 if (resource_type(res) != resource_type(window->res))
  82                         continue;
  83
  84                 bus_region.start = window->res->start - window->offset;
  85                 bus_region.end = window->res->end - window->offset;
  86
  87                 if (region_contains(&bus_region, region)) {
  88                         offset = window->offset;
  89                         break;
  90                 }
  91         }
  92
  93         res->start = region->start + offset;
  94         res->end = region->end + offset;
  95 }
  96 EXPORT_SYMBOL(pcibios_bus_to_resource);