From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
The static MCFG table tells us the base of MMCFG space, but it does not
reserve the space -- the reservation should be done via a device in the
ACPI namespace whose _CRS includes the MMCFG region.
Replace find_mboard_resource(), which already searches for such a device,
with the new acpi_resource_consumer() interface that does essentially the
same thing.
acpi_resource_consumer() is not as strict as find_mboard_resource() was:
find_mboard_resource() only looks at PNP0C01 and PNP0C02 devices and the
following _CRS descriptor types:
ACPI_RESOURCE_TYPE_FIXED_MEMORY32
ACPI_RESOURCE_TYPE_ADDRESS32
ACPI_RESOURCE_TYPE_ADDRESS64
but acpi_resource_consumer() looks at *all* devices in the namespace and
the following descriptor types:
ACPI_RESOURCE_TYPE_MEMORY24
ACPI_RESOURCE_TYPE_MEMORY32
ACPI_RESOURCE_TYPE_FIXED_MEMORY32
ACPI_RESOURCE_TYPE_ADDRESS16
ACPI_RESOURCE_TYPE_ADDRESS32
ACPI_RESOURCE_TYPE_ADDRESS64
ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64
I think it is correct to accept the larger set of descriptor types.
Note 2 to Table 4-2 of the PCI Firmware spec r3.2 does suggest that the
MMCFG region should be declared by a PNP0C02 device. I don't know why it
calls out PNP0C02 specifically, unless it's related to the fact that the
Consumer/Producer issues make it hard to use the PNP0A03 device itself.
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
arch/x86/pci/mmconfig-shared.c | 69 +++++-----------------------------------
1 file changed, 9 insertions(+), 60 deletions(-)
diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c
index dd30b7e..f62ffe7 100644
--- a/arch/x86/pci/mmconfig-shared.c
+++ b/arch/x86/pci/mmconfig-shared.c
@@ -373,71 +373,20 @@ static int __init pci_mmcfg_check_hostbridge(void)
return !list_empty(&pci_mmcfg_list);
}
-static acpi_status check_mcfg_resource(struct acpi_resource *res, void *data)
-{
- struct resource *mcfg_res = data;
- struct acpi_resource_address64 address;
- acpi_status status;
-
- if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
- struct acpi_resource_fixed_memory32 *fixmem32 =
- &res->data.fixed_memory32;
- if (!fixmem32)
- return AE_OK;
- if ((mcfg_res->start >= fixmem32->address) &&
- (mcfg_res->end < (fixmem32->address +
- fixmem32->address_length))) {
- mcfg_res->flags = 1;
- return AE_CTRL_TERMINATE;
- }
- }
- if ((res->type != ACPI_RESOURCE_TYPE_ADDRESS32) &&
- (res->type != ACPI_RESOURCE_TYPE_ADDRESS64))
- return AE_OK;
-
- status = acpi_resource_to_address64(res, &address);
- if (ACPI_FAILURE(status) ||
- (address.address.address_length <= 0) ||
- (address.resource_type != ACPI_MEMORY_RANGE))
- return AE_OK;
-
- if ((mcfg_res->start >= address.address.minimum) &&
- (mcfg_res->end < (address.address.minimum + address.address.address_length))) {
- mcfg_res->flags = 1;
- return AE_CTRL_TERMINATE;
- }
- return AE_OK;
-}
-
-static acpi_status find_mboard_resource(acpi_handle handle, u32 lvl,
- void *context, void **rv)
-{
- struct resource *mcfg_res = context;
-
- acpi_walk_resources(handle, METHOD_NAME__CRS,
- check_mcfg_resource, context);
-
- if (mcfg_res->flags)
- return AE_CTRL_TERMINATE;
-
- return AE_OK;
-}
-
static int is_acpi_reserved(u64 start, u64 end, unsigned not_used)
{
struct resource mcfg_res;
+ struct acpi_device *adev;
mcfg_res.start = start;
mcfg_res.end = end - 1;
- mcfg_res.flags = 0;
+ mcfg_res.flags = IORESOURCE_MEM;
- acpi_get_devices("PNP0C01", find_mboard_resource, &mcfg_res, NULL);
-
- if (!mcfg_res.flags)
- acpi_get_devices("PNP0C02", find_mboard_resource, &mcfg_res,
- NULL);
+ adev = acpi_resource_consumer(&mcfg_res);
+ if (adev)
+ return 1;
- return mcfg_res.flags;
+ return 0;
}
typedef int (*check_reserved_t)(u64 start, u64 end, unsigned type);
@@ -450,7 +399,7 @@ static int __ref is_mmconf_reserved(check_reserved_t is_reserved,
u64 size = resource_size(&cfg->res);
u64 old_size = size;
int num_buses;
- char *method = with_e820 ? "E820" : "ACPI motherboard resources";
+ char *method = with_e820 ? "E820" : "ACPI namespace";
while (!is_reserved(addr, addr + size, E820_RESERVED)) {
size >>= 1;
@@ -504,12 +453,12 @@ static int __ref pci_mmcfg_check_reserved(struct device *dev,
if (dev)
dev_info(dev, FW_INFO
"MMCONFIG at %pR not reserved in "
- "ACPI motherboard resources\n",
+ "ACPI namespace\n",
&cfg->res);
else
pr_info(FW_INFO PREFIX
"MMCONFIG at %pR not reserved in "
- "ACPI motherboard resources\n",
+ "ACPI namespace\n",
&cfg->res);
}
--
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