Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-10 22:21:40 +00:00
Code Issues Packages Projects Releases Wiki Activity

ACPI: processor: add internal processor_physically_present()

Browse Source 
Detect if a processor is physically present before evaluating _PDC.

We want this because some BIOS will provide a _PDC even for processors
that are not present. These bogus _PDC methods then attempt to load
non-existent tables, which causes problems.

Avoid those bogus landmines.

Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Alex Chiang 2010-02-22 12:11:29 -07:00 committed by Len Brown
parent 78ed8bd294
commit 5d554a7bb0
1 changed files with 42 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
drivers/acpi/processor_core.c
View File

@ -194,6 +194,45 @@ int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
EXPORT_SYMBOL_GPL(acpi_get_cpuid);
#endif
static bool processor_physically_present(acpi_handle handle)
{
int cpuid, type;
u32 acpi_id;
acpi_status status;
acpi_object_type acpi_type;
unsigned long long tmp;
union acpi_object object = { 0 };
struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
status = acpi_get_type(handle, &acpi_type);
if (ACPI_FAILURE(status))
return false;
switch (acpi_type) {
case ACPI_TYPE_PROCESSOR:
status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
if (ACPI_FAILURE(status))
return false;
acpi_id = object.processor.proc_id;
break;
case ACPI_TYPE_DEVICE:
status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
if (ACPI_FAILURE(status))
return false;
acpi_id = tmp;
break;
default:
return false;
}
type = (acpi_type == ACPI_TYPE_DEVICE) ? 1 : 0;
cpuid = acpi_get_cpuid(handle, type, acpi_id);
if (cpuid == -1)
return false;
return true;
}
static void acpi_set_pdc_bits(u32 *buf)
{
@ -335,6 +374,9 @@ static struct dmi_system_id __cpuinitdata early_pdc_optin_table[] = {
static acpi_status
early_init_pdc(acpi_handle handle, u32 lvl, void *context, void **rv)
{
if (processor_physically_present(handle) == false)
return AE_OK;
acpi_processor_set_pdc(handle);
return AE_OK;
}