swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 52addcf9d6669fa439387610bc65c92fa0980cef authored by Linus Torvalds on 25 August 2014, 22:36:20 UTC
Linux 3.17-rc2
Linux 3.17-rc2
Tip revision: 52addcf
processor_core.c
/*
* Copyright (C) 2005 Intel Corporation
* Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
*
* Alex Chiang <achiang@hp.com>
* - Unified x86/ia64 implementations
*/
#include <linux/export.h>
#include <linux/acpi.h>
#include <acpi/processor.h>
#define _COMPONENT ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME("processor_core");
static int map_lapic_id(struct acpi_subtable_header *entry,
u32 acpi_id, int *apic_id)
{
struct acpi_madt_local_apic *lapic =
(struct acpi_madt_local_apic *)entry;
if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;
if (lapic->processor_id != acpi_id)
return -EINVAL;
*apic_id = lapic->id;
return 0;
}
static int map_x2apic_id(struct acpi_subtable_header *entry,
int device_declaration, u32 acpi_id, int *apic_id)
{
struct acpi_madt_local_x2apic *apic =
(struct acpi_madt_local_x2apic *)entry;
if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;
if (device_declaration && (apic->uid == acpi_id)) {
*apic_id = apic->local_apic_id;
return 0;
}
return -EINVAL;
}
static int map_lsapic_id(struct acpi_subtable_header *entry,
int device_declaration, u32 acpi_id, int *apic_id)
{
struct acpi_madt_local_sapic *lsapic =
(struct acpi_madt_local_sapic *)entry;
if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
return -ENODEV;
if (device_declaration) {
if ((entry->length < 16) || (lsapic->uid != acpi_id))
return -EINVAL;
} else if (lsapic->processor_id != acpi_id)
return -EINVAL;
*apic_id = (lsapic->id << 8) | lsapic->eid;
return 0;
}
static int map_madt_entry(int type, u32 acpi_id)
{
unsigned long madt_end, entry;
static struct acpi_table_madt *madt;
static int read_madt;
int apic_id = -1;
if (!read_madt) {
if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
(struct acpi_table_header **)&madt)))
madt = NULL;
read_madt++;
}
if (!madt)
return apic_id;
entry = (unsigned long)madt;
madt_end = entry + madt->header.length;
/* Parse all entries looking for a match. */
entry += sizeof(struct acpi_table_madt);
while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
struct acpi_subtable_header *header =
(struct acpi_subtable_header *)entry;
if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
if (!map_lapic_id(header, acpi_id, &apic_id))
break;
} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
if (!map_x2apic_id(header, type, acpi_id, &apic_id))
break;
} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
if (!map_lsapic_id(header, type, acpi_id, &apic_id))
break;
}
entry += header->length;
}
return apic_id;
}
static int map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
struct acpi_subtable_header *header;
int apic_id = -1;
if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
goto exit;
if (!buffer.length || !buffer.pointer)
goto exit;
obj = buffer.pointer;
if (obj->type != ACPI_TYPE_BUFFER ||
obj->buffer.length < sizeof(struct acpi_subtable_header)) {
goto exit;
}
header = (struct acpi_subtable_header *)obj->buffer.pointer;
if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
map_lapic_id(header, acpi_id, &apic_id);
} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
map_lsapic_id(header, type, acpi_id, &apic_id);
} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
map_x2apic_id(header, type, acpi_id, &apic_id);
}
exit:
kfree(buffer.pointer);
return apic_id;
}
int acpi_get_apicid(acpi_handle handle, int type, u32 acpi_id)
{
int apic_id;
apic_id = map_mat_entry(handle, type, acpi_id);
if (apic_id == -1)
apic_id = map_madt_entry(type, acpi_id);
return apic_id;
}
int acpi_map_cpuid(int apic_id, u32 acpi_id)
{
#ifdef CONFIG_SMP
int i;
#endif
if (apic_id == -1) {
/*
* On UP processor, there is no _MAT or MADT table.
* So above apic_id is always set to -1.
*
* BIOS may define multiple CPU handles even for UP processor.
* For example,
*
* Scope (_PR)
* {
* Processor (CPU0, 0x00, 0x00000410, 0x06) {}
* Processor (CPU1, 0x01, 0x00000410, 0x06) {}
* Processor (CPU2, 0x02, 0x00000410, 0x06) {}
* Processor (CPU3, 0x03, 0x00000410, 0x06) {}
* }
*
* Ignores apic_id and always returns 0 for the processor
* handle with acpi id 0 if nr_cpu_ids is 1.
* This should be the case if SMP tables are not found.
* Return -1 for other CPU's handle.
*/
if (nr_cpu_ids <= 1 && acpi_id == 0)
return acpi_id;
else
return apic_id;
}
#ifdef CONFIG_SMP
for_each_possible_cpu(i) {
if (cpu_physical_id(i) == apic_id)
return i;
}
#else
/* In UP kernel, only processor 0 is valid */
if (apic_id == 0)
return apic_id;
#endif
return -1;
}
int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
{
int apic_id;
apic_id = acpi_get_apicid(handle, type, acpi_id);
return acpi_map_cpuid(apic_id, acpi_id);
}
EXPORT_SYMBOL_GPL(acpi_get_cpuid);