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 EXPORT_SYMBOL_GPL(pci_get_host_bridge_device); 37 38 void pci_put_host_bridge_device(struct device *dev) 39 { 40 kobject_put(&dev->kobj); 41 } 42 43 void 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 } 50 EXPORT_SYMBOL_GPL(pci_set_host_bridge_release); 51 52 void 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 } 69 EXPORT_SYMBOL(pcibios_resource_to_bus); 70 71 static 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 77 void 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 } 102 EXPORT_SYMBOL(pcibios_bus_to_resource); 103