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
12static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
13{
14	while (bus->parent)
15		bus = bus->parent;
16
17	return bus;
18}
19
20static struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus)
21{
22	struct pci_bus *root_bus = find_pci_root_bus(bus);
23
24	return to_pci_host_bridge(root_bus->bridge);
25}
26
27void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
28				 void (*release_fn)(struct pci_host_bridge *),
29				 void *release_data)
30{
31	bridge->release_fn = release_fn;
32	bridge->release_data = release_data;
33}
34
35void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
36			     struct resource *res)
37{
38	struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
39	struct pci_host_bridge_window *window;
40	resource_size_t offset = 0;
41
42	list_for_each_entry(window, &bridge->windows, list) {
43		if (resource_contains(window->res, res)) {
44			offset = window->offset;
45			break;
46		}
47	}
48
49	region->start = res->start - offset;
50	region->end = res->end - offset;
51}
52EXPORT_SYMBOL(pcibios_resource_to_bus);
53
54static bool region_contains(struct pci_bus_region *region1,
55			    struct pci_bus_region *region2)
56{
57	return region1->start <= region2->start && region1->end >= region2->end;
58}
59
60void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
61			     struct pci_bus_region *region)
62{
63	struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
64	struct pci_host_bridge_window *window;
65	resource_size_t offset = 0;
66
67	list_for_each_entry(window, &bridge->windows, list) {
68		struct pci_bus_region bus_region;
69
70		if (resource_type(res) != resource_type(window->res))
71			continue;
72
73		bus_region.start = window->res->start - window->offset;
74		bus_region.end = window->res->end - window->offset;
75
76		if (region_contains(&bus_region, region)) {
77			offset = window->offset;
78			break;
79		}
80	}
81
82	res->start = region->start + offset;
83	res->end = region->end + offset;
84}
85EXPORT_SYMBOL(pcibios_bus_to_resource);