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linux/arch/x86/pci/acpi.c
Bjorn Helgaas 7bc5e3f2be x86/PCI: use host bridge _CRS info by default on 2008 and newer machines
The main benefit of using ACPI host bridge window information is that
we can do better resource allocation in systems with multiple host bridges,
e.g., http://bugzilla.kernel.org/show_bug.cgi?id=14183

Sometimes we need _CRS information even if we only have one host bridge,
e.g., https://bugs.launchpad.net/ubuntu/+source/linux/+bug/341681

Most of these systems are relatively new, so this patch turns on
"pci=use_crs" only on machines with a BIOS date of 2008 or newer.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-23 09:43:42 -08:00

326 lines
7.6 KiB
C

#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/dmi.h>
#include <asm/numa.h>
#include <asm/pci_x86.h>
struct pci_root_info {
struct acpi_device *bridge;
char *name;
unsigned int res_num;
struct resource *res;
struct pci_bus *bus;
int busnum;
};
static bool pci_use_crs = true;
static int __init set_use_crs(const struct dmi_system_id *id)
{
pci_use_crs = true;
return 0;
}
static const struct dmi_system_id pci_use_crs_table[] __initconst = {
/* http://bugzilla.kernel.org/show_bug.cgi?id=14183 */
{
.callback = set_use_crs,
.ident = "IBM System x3800",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
DMI_MATCH(DMI_PRODUCT_NAME, "x3800"),
},
},
{}
};
void __init pci_acpi_crs_quirks(void)
{
int year;
if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year < 2008)
pci_use_crs = false;
dmi_check_system(pci_use_crs_table);
/*
* If the user specifies "pci=use_crs" or "pci=nocrs" explicitly, that
* takes precedence over anything we figured out above.
*/
if (pci_probe & PCI_ROOT_NO_CRS)
pci_use_crs = false;
else if (pci_probe & PCI_USE__CRS)
pci_use_crs = true;
printk(KERN_INFO "PCI: %s host bridge windows from ACPI; "
"if necessary, use \"pci=%s\" and report a bug\n",
pci_use_crs ? "Using" : "Ignoring",
pci_use_crs ? "nocrs" : "use_crs");
}
static acpi_status
resource_to_addr(struct acpi_resource *resource,
struct acpi_resource_address64 *addr)
{
acpi_status status;
status = acpi_resource_to_address64(resource, addr);
if (ACPI_SUCCESS(status) &&
(addr->resource_type == ACPI_MEMORY_RANGE ||
addr->resource_type == ACPI_IO_RANGE) &&
addr->address_length > 0 &&
addr->producer_consumer == ACPI_PRODUCER) {
return AE_OK;
}
return AE_ERROR;
}
static acpi_status
count_resource(struct acpi_resource *acpi_res, void *data)
{
struct pci_root_info *info = data;
struct acpi_resource_address64 addr;
acpi_status status;
status = resource_to_addr(acpi_res, &addr);
if (ACPI_SUCCESS(status))
info->res_num++;
return AE_OK;
}
static void
align_resource(struct acpi_device *bridge, struct resource *res)
{
int align = (res->flags & IORESOURCE_MEM) ? 16 : 4;
/*
* Host bridge windows are not BARs, but the decoders on the PCI side
* that claim this address space have starting alignment and length
* constraints, so fix any obvious BIOS goofs.
*/
if (!IS_ALIGNED(res->start, align)) {
dev_printk(KERN_DEBUG, &bridge->dev,
"host bridge window %pR invalid; "
"aligning start to %d-byte boundary\n", res, align);
res->start &= ~(align - 1);
}
if (!IS_ALIGNED(res->end + 1, align)) {
dev_printk(KERN_DEBUG, &bridge->dev,
"host bridge window %pR invalid; "
"aligning end to %d-byte boundary\n", res, align);
res->end = ALIGN(res->end, align) - 1;
}
}
static acpi_status
setup_resource(struct acpi_resource *acpi_res, void *data)
{
struct pci_root_info *info = data;
struct resource *res;
struct acpi_resource_address64 addr;
acpi_status status;
unsigned long flags;
struct resource *root;
u64 start, end;
status = resource_to_addr(acpi_res, &addr);
if (!ACPI_SUCCESS(status))
return AE_OK;
if (addr.resource_type == ACPI_MEMORY_RANGE) {
root = &iomem_resource;
flags = IORESOURCE_MEM;
if (addr.info.mem.caching == ACPI_PREFETCHABLE_MEMORY)
flags |= IORESOURCE_PREFETCH;
} else if (addr.resource_type == ACPI_IO_RANGE) {
root = &ioport_resource;
flags = IORESOURCE_IO;
} else
return AE_OK;
start = addr.minimum + addr.translation_offset;
end = start + addr.address_length - 1;
res = &info->res[info->res_num];
res->name = info->name;
res->flags = flags;
res->start = start;
res->end = end;
res->child = NULL;
align_resource(info->bridge, res);
if (!pci_use_crs) {
dev_printk(KERN_DEBUG, &info->bridge->dev,
"host bridge window %pR (ignored)\n", res);
return AE_OK;
}
if (insert_resource(root, res)) {
dev_err(&info->bridge->dev,
"can't allocate host bridge window %pR\n", res);
} else {
pci_bus_add_resource(info->bus, res, 0);
info->res_num++;
if (addr.translation_offset)
dev_info(&info->bridge->dev, "host bridge window %pR "
"(PCI address [%#llx-%#llx])\n",
res, res->start - addr.translation_offset,
res->end - addr.translation_offset);
else
dev_info(&info->bridge->dev,
"host bridge window %pR\n", res);
}
return AE_OK;
}
static void
get_current_resources(struct acpi_device *device, int busnum,
int domain, struct pci_bus *bus)
{
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;
acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_resource,
&info);
if (!info.res_num)
return;
size = sizeof(*info.res) * info.res_num;
info.res = kmalloc(size, GFP_KERNEL);
if (!info.res)
goto res_alloc_fail;
info.name = kmalloc(16, GFP_KERNEL);
if (!info.name)
goto name_alloc_fail;
sprintf(info.name, "PCI Bus %04x:%02x", domain, busnum);
info.res_num = 0;
acpi_walk_resources(device->handle, METHOD_NAME__CRS, setup_resource,
&info);
return;
name_alloc_fail:
kfree(info.res);
res_alloc_fail:
return;
}
struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_device *device, int domain, int busnum)
{
struct pci_bus *bus;
struct pci_sysdata *sd;
int node;
#ifdef CONFIG_ACPI_NUMA
int pxm;
#endif
if (domain && !pci_domains_supported) {
printk(KERN_WARNING "pci_bus %04x:%02x: "
"ignored (multiple domains not supported)\n",
domain, busnum);
return NULL;
}
node = -1;
#ifdef CONFIG_ACPI_NUMA
pxm = acpi_get_pxm(device->handle);
if (pxm >= 0)
node = pxm_to_node(pxm);
if (node != -1)
set_mp_bus_to_node(busnum, node);
else
#endif
node = get_mp_bus_to_node(busnum);
if (node != -1 && !node_online(node))
node = -1;
/* Allocate per-root-bus (not per bus) arch-specific data.
* TODO: leak; this memory is never freed.
* It's arguable whether it's worth the trouble to care.
*/
sd = kzalloc(sizeof(*sd), GFP_KERNEL);
if (!sd) {
printk(KERN_WARNING "pci_bus %04x:%02x: "
"ignored (out of memory)\n", domain, busnum);
return NULL;
}
sd->domain = domain;
sd->node = node;
/*
* Maybe the desired pci bus has been already scanned. In such case
* it is unnecessary to scan the pci bus with the given domain,busnum.
*/
bus = pci_find_bus(domain, busnum);
if (bus) {
/*
* If the desired bus exits, the content of bus->sysdata will
* be replaced by sd.
*/
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);
bus->subordinate = pci_scan_child_bus(bus);
}
}
if (!bus)
kfree(sd);
if (bus && node != -1) {
#ifdef CONFIG_ACPI_NUMA
if (pxm >= 0)
dev_printk(KERN_DEBUG, &bus->dev,
"on NUMA node %d (pxm %d)\n", node, pxm);
#else
dev_printk(KERN_DEBUG, &bus->dev, "on NUMA node %d\n", node);
#endif
}
return bus;
}
int __init pci_acpi_init(void)
{
struct pci_dev *dev = NULL;
if (pcibios_scanned)
return 0;
if (acpi_noirq)
return 0;
printk(KERN_INFO "PCI: Using ACPI for IRQ routing\n");
acpi_irq_penalty_init();
pcibios_scanned++;
pcibios_enable_irq = acpi_pci_irq_enable;
pcibios_disable_irq = acpi_pci_irq_disable;
if (pci_routeirq) {
/*
* PCI IRQ routing is set up by pci_enable_device(), but we
* also do it here in case there are still broken drivers that
* don't use pci_enable_device().
*/
printk(KERN_INFO "PCI: Routing PCI interrupts for all devices because \"pci=routeirq\" specified\n");
for_each_pci_dev(dev)
acpi_pci_irq_enable(dev);
}
return 0;
}