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 12 static 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 20 struct 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 } 26 EXPORT_SYMBOL_GPL(pci_find_host_bridge); 27 28 struct 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 } 36 37 void pci_put_host_bridge_device(struct device *dev) 38 { 39 kobject_put(&dev->kobj); 40 } 41 42 void pci_set_host_bridge_release(struct pci_host_bridge *bridge, 43 void (*release_fn)(struct pci_host_bridge *), 44 void *release_data) 45 { 46 bridge->release_fn = release_fn; 47 bridge->release_data = release_data; 48 } 49 EXPORT_SYMBOL_GPL(pci_set_host_bridge_release); 50 51 void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region, 52 struct resource *res) 53 { 54 struct pci_host_bridge *bridge = pci_find_host_bridge(bus); 55 struct resource_entry *window; 56 resource_size_t offset = 0; 57 58 resource_list_for_each_entry(window, &bridge->windows) { 59 if (resource_contains(window->res, res)) { 60 offset = window->offset; 61 break; 62 } 63 } 64 65 region->start = res->start - offset; 66 region->end = res->end - offset; 67 } 68 EXPORT_SYMBOL(pcibios_resource_to_bus); 69 70 static bool region_contains(struct pci_bus_region *region1, 71 struct pci_bus_region *region2) 72 { 73 return region1->start <= region2->start && region1->end >= region2->end; 74 } 75 76 void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res, 77 struct pci_bus_region *region) 78 { 79 struct pci_host_bridge *bridge = pci_find_host_bridge(bus); 80 struct resource_entry *window; 81 resource_size_t offset = 0; 82 83 resource_list_for_each_entry(window, &bridge->windows) { 84 struct pci_bus_region bus_region; 85 86 if (resource_type(res) != resource_type(window->res)) 87 continue; 88 89 bus_region.start = window->res->start - window->offset; 90 bus_region.end = window->res->end - window->offset; 91 92 if (region_contains(&bus_region, region)) { 93 offset = window->offset; 94 break; 95 } 96 } 97 98 res->start = region->start + offset; 99 res->end = region->end + offset; 100 } 101 EXPORT_SYMBOL(pcibios_bus_to_resource); 102