x86/PCI: convert to pci_create_root_bus() and pci_scan_root_bus()
x86 has two kinds of PCI root bus scanning:
(1) ACPI-based, using _CRS resources. This used pci_create_bus(), not
pci_scan_bus(), because ACPI hotplug needed to split the
pci_bus_add_devices() into a separate host bridge .start() method.
This patch parses the _CRS resources earlier, so we can build a list of
resources and pass it to pci_create_root_bus().
Note that as before, we parse the _CRS even if we aren't going to use
it so we can print it for debugging purposes.
(2) All other, which used either default resources (ioport_resource and
iomem_resource) or information read from the hardware via amd_bus.c or
similar. This used pci_scan_bus().
This patch converts x86_pci_root_bus_res_quirks() (previously called
from pcibios_fixup_bus()) to x86_pci_root_bus_resources(), which builds
a list of resources before we call pci_scan_root_bus().
We also use x86_pci_root_bus_resources() if we have ACPI but are
ignoring _CRS.
CC: Yinghai Lu <yinghai.lu@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index 425500b..a312e76 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -12,7 +12,7 @@
char *name;
unsigned int res_num;
struct resource *res;
- struct pci_bus *bus;
+ struct list_head *resources;
int busnum;
};
@@ -304,23 +304,20 @@
"ignoring host bridge window %pR (conflicts with %s %pR)\n",
res, conflict->name, conflict);
else
- pci_bus_add_resource(info->bus, res, 0);
+ pci_add_resource(info->resources, res);
}
}
static void
get_current_resources(struct acpi_device *device, int busnum,
- int domain, struct pci_bus *bus)
+ int domain, struct list_head *resources)
{
struct pci_root_info info;
size_t size;
- if (pci_use_crs)
- pci_bus_remove_resources(bus);
-
info.bridge = device;
- info.bus = bus;
info.res_num = 0;
+ info.resources = resources;
acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_resource,
&info);
if (!info.res_num)
@@ -329,7 +326,7 @@
size = sizeof(*info.res) * info.res_num;
info.res = kmalloc(size, GFP_KERNEL);
if (!info.res)
- goto res_alloc_fail;
+ return;
info.name = kasprintf(GFP_KERNEL, "PCI Bus %04x:%02x", domain, busnum);
if (!info.name)
@@ -344,8 +341,6 @@
name_alloc_fail:
kfree(info.res);
-res_alloc_fail:
- return;
}
struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root)
@@ -353,6 +348,7 @@
struct acpi_device *device = root->device;
int domain = root->segment;
int busnum = root->secondary.start;
+ LIST_HEAD(resources);
struct pci_bus *bus;
struct pci_sysdata *sd;
int node;
@@ -407,11 +403,15 @@
memcpy(bus->sysdata, sd, sizeof(*sd));
kfree(sd);
} else {
- bus = pci_create_bus(NULL, busnum, &pci_root_ops, sd);
- if (bus) {
- get_current_resources(device, busnum, domain, bus);
+ get_current_resources(device, busnum, domain, &resources);
+ if (list_empty(&resources))
+ x86_pci_root_bus_resources(busnum, &resources);
+ bus = pci_create_root_bus(NULL, busnum, &pci_root_ops, sd,
+ &resources);
+ if (bus)
bus->subordinate = pci_scan_child_bus(bus);
- }
+ else
+ pci_free_resource_list(&resources);
}
/* After the PCI-E bus has been walked and all devices discovered,