linux/arch/x86/pci/acpi.c
Bjorn Helgaas 2fe2abf896 PCI: augment bus resource table with a list
Previously we used a table of size PCI_BUS_NUM_RESOURCES (16) for resources
forwarded to a bus by its upstream bridge.  We've increased this size
several times when the table overflowed.

But there's no good limit on the number of resources because host bridges
and subtractive decode bridges can forward any number of ranges to their
secondary buses.

This patch reduces the table to only PCI_BRIDGE_RESOURCE_NUM (4) entries,
which corresponds to the number of windows a PCI-to-PCI (3) or CardBus (4)
bridge can positively decode.  Any additional resources, e.g., PCI host
bridge windows or subtractively-decoded regions, are kept in a list.

I'd prefer a single list rather than this split table/list approach, but
that requires simultaneous changes to every architecture.  This approach
only requires immediate changes where we set up (a) host bridges with more
than four windows and (b) subtractive-decode P2P bridges, and we can
incrementally change other architectures to use the list.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-02-23 09:43:37 -08:00

285 lines
6.7 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 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_probe & 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_probe & PCI_USE__CRS)
pci_bus_remove_resources(bus);
else
dev_info(&device->dev,
"ignoring host bridge windows from ACPI; "
"boot with \"pci=use_crs\" to use them\n");
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;
}