linux/drivers/pci/host-bridge.c

102 lines
2.3 KiB
C
Raw Normal View History

/*
* host bridge related code
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/module.h>
#include "pci.h"
static LIST_HEAD(pci_host_bridges);
void add_to_pci_host_bridges(struct pci_host_bridge *bridge)
{
list_add_tail(&bridge->list, &pci_host_bridges);
}
static struct pci_bus *find_pci_root_bus(struct pci_dev *dev)
{
struct pci_bus *bus;
bus = dev->bus;
while (bus->parent)
bus = bus->parent;
return bus;
}
static struct pci_host_bridge *find_pci_host_bridge(struct pci_dev *dev)
{
struct pci_bus *bus = find_pci_root_bus(dev);
struct pci_host_bridge *bridge;
list_for_each_entry(bridge, &pci_host_bridges, list) {
if (bridge->bus == bus)
return bridge;
}
return NULL;
}
static bool resource_contains(struct resource *res1, struct resource *res2)
{
return res1->start <= res2->start && res1->end >= res2->end;
}
void pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
struct resource *res)
{
struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
struct pci_host_bridge_window *window;
resource_size_t offset = 0;
list_for_each_entry(window, &bridge->windows, list) {
if (resource_type(res) != resource_type(window->res))
continue;
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_dev *dev, struct resource *res,
struct pci_bus_region *region)
{
struct pci_host_bridge *bridge = find_pci_host_bridge(dev);
struct pci_host_bridge_window *window;
resource_size_t offset = 0;
list_for_each_entry(window, &bridge->windows, list) {
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);