linux/linux-5.18.11/drivers/pci/host-bridge.c

102 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Host bridge related code
*/
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/module.h>
#include "pci.h"
static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
{
while (bus->parent)
bus = bus->parent;
return bus;
}
struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus)
{
struct pci_bus *root_bus = find_pci_root_bus(bus);
return to_pci_host_bridge(root_bus->bridge);
}
EXPORT_SYMBOL_GPL(pci_find_host_bridge);
struct device *pci_get_host_bridge_device(struct pci_dev *dev)
{
struct pci_bus *root_bus = find_pci_root_bus(dev->bus);
struct device *bridge = root_bus->bridge;
kobject_get(&bridge->kobj);
return bridge;
}
void pci_put_host_bridge_device(struct device *dev)
{
kobject_put(&dev->kobj);
}
void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
void (*release_fn)(struct pci_host_bridge *),
void *release_data)
{
bridge->release_fn = release_fn;
bridge->release_data = release_data;
}
EXPORT_SYMBOL_GPL(pci_set_host_bridge_release);
void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
struct resource *res)
{
struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
struct resource_entry *window;
resource_size_t offset = 0;
resource_list_for_each_entry(window, &bridge->windows) {
if (resource_contains(window->res, res)) {
offset = window->offset;
break;
}
}
region->start = res->start - offset;
region->end = res->end - offset;
}
EXPORT_SYMBOL(pcibios_resource_to_bus);
static bool region_contains(struct pci_bus_region *region1,
struct pci_bus_region *region2)
{
return region1->start <= region2->start && region1->end >= region2->end;
}
void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
struct pci_bus_region *region)
{
struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
struct resource_entry *window;
resource_size_t offset = 0;
resource_list_for_each_entry(window, &bridge->windows) {
struct pci_bus_region bus_region;
if (resource_type(res) != resource_type(window->res))
continue;
bus_region.start = window->res->start - window->offset;
bus_region.end = window->res->end - window->offset;
if (region_contains(&bus_region, region)) {
offset = window->offset;
break;
}
}
res->start = region->start + offset;
res->end = region->end + offset;
}
EXPORT_SYMBOL(pcibios_bus_to_resource);