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