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
11static 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
19struct 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
26struct 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
35void  pci_put_host_bridge_device(struct device *dev)
36{
37	kobject_put(&dev->kobj);
38}
39
40void 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}
47EXPORT_SYMBOL_GPL(pci_set_host_bridge_release);
48
49void 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}
66EXPORT_SYMBOL(pcibios_resource_to_bus);
67
68static 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
74void 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}
99EXPORT_SYMBOL(pcibios_bus_to_resource);