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102 lines · 2.5 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Host bridge related code
4 */
5
6#include <linux/kernel.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
20struct pci_host_bridge *pci_find_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}
26EXPORT_SYMBOL_GPL(pci_find_host_bridge);
27
28struct device *pci_get_host_bridge_device(struct pci_dev *dev)
29{
30 struct pci_bus *root_bus = find_pci_root_bus(dev->bus);
31 struct device *bridge = root_bus->bridge;
32
33 kobject_get(&bridge->kobj);
34 return bridge;
35}
36EXPORT_SYMBOL_GPL(pci_get_host_bridge_device);
37
38void pci_put_host_bridge_device(struct device *dev)
39{
40 kobject_put(&dev->kobj);
41}
42
43void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
44 void (*release_fn)(struct pci_host_bridge *),
45 void *release_data)
46{
47 bridge->release_fn = release_fn;
48 bridge->release_data = release_data;
49}
50EXPORT_SYMBOL_GPL(pci_set_host_bridge_release);
51
52void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
53 struct resource *res)
54{
55 struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
56 struct resource_entry *window;
57 resource_size_t offset = 0;
58
59 resource_list_for_each_entry(window, &bridge->windows) {
60 if (resource_contains(window->res, res)) {
61 offset = window->offset;
62 break;
63 }
64 }
65
66 region->start = res->start - offset;
67 region->end = res->end - offset;
68}
69EXPORT_SYMBOL(pcibios_resource_to_bus);
70
71static bool region_contains(struct pci_bus_region *region1,
72 struct pci_bus_region *region2)
73{
74 return region1->start <= region2->start && region1->end >= region2->end;
75}
76
77void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
78 struct pci_bus_region *region)
79{
80 struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
81 struct resource_entry *window;
82 resource_size_t offset = 0;
83
84 resource_list_for_each_entry(window, &bridge->windows) {
85 struct pci_bus_region bus_region;
86
87 if (resource_type(res) != resource_type(window->res))
88 continue;
89
90 bus_region.start = window->res->start - window->offset;
91 bus_region.end = window->res->end - window->offset;
92
93 if (region_contains(&bus_region, region)) {
94 offset = window->offset;
95 break;
96 }
97 }
98
99 res->start = region->start + offset;
100 res->end = region->end + offset;
101}
102EXPORT_SYMBOL(pcibios_bus_to_resource);