Contributors: 51
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Rafael J. Wysocki |
1321 |
40.78% |
13 |
11.02% |
| Andy Grover |
412 |
12.72% |
7 |
5.93% |
| Dou Liyang |
339 |
10.47% |
5 |
4.24% |
| Srinivas Pandruvada |
272 |
8.40% |
1 |
0.85% |
| Len Brown |
167 |
5.16% |
11 |
9.32% |
| Chen Yu |
86 |
2.66% |
1 |
0.85% |
| Toshi Kani |
65 |
2.01% |
4 |
3.39% |
| Ashwin Chaugule |
63 |
1.95% |
1 |
0.85% |
| Thomas Renninger |
54 |
1.67% |
5 |
4.24% |
| Alexey Y. Starikovskiy |
54 |
1.67% |
4 |
3.39% |
| Hanjun Guo |
49 |
1.51% |
8 |
6.78% |
| Sudeep Holla |
48 |
1.48% |
3 |
2.54% |
| Björn Helgaas |
43 |
1.33% |
5 |
4.24% |
| Jiang Liu |
32 |
0.99% |
3 |
2.54% |
| Patrick Mochel |
21 |
0.65% |
5 |
4.24% |
| Greg Kroah-Hartman |
19 |
0.59% |
1 |
0.85% |
| Myron Stowe |
19 |
0.59% |
2 |
1.69% |
| Alexander Chiang |
17 |
0.52% |
1 |
0.85% |
| Rui Zhang |
16 |
0.49% |
3 |
2.54% |
| Mike Travis |
13 |
0.40% |
2 |
1.69% |
| Jiri Slaby |
13 |
0.40% |
1 |
0.85% |
| Rusty Russell |
13 |
0.40% |
2 |
1.69% |
| Wen Congyang |
10 |
0.31% |
1 |
0.85% |
| Lan Tianyu |
9 |
0.28% |
1 |
0.85% |
| Gu Zheng |
9 |
0.28% |
1 |
0.85% |
| Vitaly Kuznetsov |
7 |
0.22% |
1 |
0.85% |
| Auke-Jan H Kok |
6 |
0.19% |
1 |
0.85% |
| Shaohua Li |
6 |
0.19% |
1 |
0.85% |
| Daniel Drake |
6 |
0.19% |
1 |
0.85% |
| Chumbalkar Nagananda |
5 |
0.15% |
1 |
0.85% |
| Dave Jones |
5 |
0.15% |
1 |
0.85% |
| Mika Westerberg |
4 |
0.12% |
2 |
1.69% |
| Dominik Brodowski |
4 |
0.12% |
1 |
0.85% |
| Sebastian Andrzej Siewior |
4 |
0.12% |
1 |
0.85% |
| Lance Ortiz |
3 |
0.09% |
1 |
0.85% |
| Xiaofei Tan |
3 |
0.09% |
1 |
0.85% |
| Kamezawa Hiroyuki |
2 |
0.06% |
1 |
0.85% |
| Thomas Gleixner |
2 |
0.06% |
1 |
0.85% |
| Janosch Machowinski |
2 |
0.06% |
1 |
0.85% |
| Graeme Gregory |
2 |
0.06% |
1 |
0.85% |
| Venkatesh Pallipadi |
2 |
0.06% |
1 |
0.85% |
| Baoquan He |
2 |
0.06% |
1 |
0.85% |
| Gustavo A. R. Silva |
2 |
0.06% |
1 |
0.85% |
| Adrian Bunk |
1 |
0.03% |
1 |
0.85% |
| Alex Hung |
1 |
0.03% |
1 |
0.85% |
| Andreas Mohr |
1 |
0.03% |
1 |
0.85% |
| Catalin Marinas |
1 |
0.03% |
1 |
0.85% |
| Ben Hutchings |
1 |
0.03% |
1 |
0.85% |
| Colin Ian King |
1 |
0.03% |
1 |
0.85% |
| Lin Ming |
1 |
0.03% |
1 |
0.85% |
| Ashok Raj |
1 |
0.03% |
1 |
0.85% |
| Total |
3239 |
|
118 |
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* acpi_processor.c - ACPI processor enumeration support
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
* Copyright (C) 2004 Dominik Brodowski <linux@brodo.de>
* Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
* Copyright (C) 2013, Intel Corporation
* Rafael J. Wysocki <rafael.j.wysocki@intel.com>
*/
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <acpi/processor.h>
#include <asm/cpu.h>
#include "internal.h"
DEFINE_PER_CPU(struct acpi_processor *, processors);
EXPORT_PER_CPU_SYMBOL(processors);
/* Errata Handling */
struct acpi_processor_errata errata __read_mostly;
EXPORT_SYMBOL_GPL(errata);
static int acpi_processor_errata_piix4(struct pci_dev *dev)
{
u8 value1 = 0;
u8 value2 = 0;
if (!dev)
return -EINVAL;
/*
* Note that 'dev' references the PIIX4 ACPI Controller.
*/
switch (dev->revision) {
case 0:
dev_dbg(&dev->dev, "Found PIIX4 A-step\n");
break;
case 1:
dev_dbg(&dev->dev, "Found PIIX4 B-step\n");
break;
case 2:
dev_dbg(&dev->dev, "Found PIIX4E\n");
break;
case 3:
dev_dbg(&dev->dev, "Found PIIX4M\n");
break;
default:
dev_dbg(&dev->dev, "Found unknown PIIX4\n");
break;
}
switch (dev->revision) {
case 0: /* PIIX4 A-step */
case 1: /* PIIX4 B-step */
/*
* See specification changes #13 ("Manual Throttle Duty Cycle")
* and #14 ("Enabling and Disabling Manual Throttle"), plus
* erratum #5 ("STPCLK# Deassertion Time") from the January
* 2002 PIIX4 specification update. Applies to only older
* PIIX4 models.
*/
errata.piix4.throttle = 1;
fallthrough;
case 2: /* PIIX4E */
case 3: /* PIIX4M */
/*
* See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
* Livelock") from the January 2002 PIIX4 specification update.
* Applies to all PIIX4 models.
*/
/*
* BM-IDE
* ------
* Find the PIIX4 IDE Controller and get the Bus Master IDE
* Status register address. We'll use this later to read
* each IDE controller's DMA status to make sure we catch all
* DMA activity.
*/
dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_82371AB,
PCI_ANY_ID, PCI_ANY_ID, NULL);
if (dev) {
errata.piix4.bmisx = pci_resource_start(dev, 4);
pci_dev_put(dev);
}
/*
* Type-F DMA
* ----------
* Find the PIIX4 ISA Controller and read the Motherboard
* DMA controller's status to see if Type-F (Fast) DMA mode
* is enabled (bit 7) on either channel. Note that we'll
* disable C3 support if this is enabled, as some legacy
* devices won't operate well if fast DMA is disabled.
*/
dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_82371AB_0,
PCI_ANY_ID, PCI_ANY_ID, NULL);
if (dev) {
pci_read_config_byte(dev, 0x76, &value1);
pci_read_config_byte(dev, 0x77, &value2);
if ((value1 & 0x80) || (value2 & 0x80))
errata.piix4.fdma = 1;
pci_dev_put(dev);
}
break;
}
if (errata.piix4.bmisx)
dev_dbg(&dev->dev, "Bus master activity detection (BM-IDE) erratum enabled\n");
if (errata.piix4.fdma)
dev_dbg(&dev->dev, "Type-F DMA livelock erratum (C3 disabled)\n");
return 0;
}
static int acpi_processor_errata(void)
{
int result = 0;
struct pci_dev *dev = NULL;
/*
* PIIX4
*/
dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
PCI_ANY_ID, NULL);
if (dev) {
result = acpi_processor_errata_piix4(dev);
pci_dev_put(dev);
}
return result;
}
/* Initialization */
#ifdef CONFIG_ACPI_HOTPLUG_CPU
int __weak acpi_map_cpu(acpi_handle handle,
phys_cpuid_t physid, u32 acpi_id, int *pcpu)
{
return -ENODEV;
}
int __weak acpi_unmap_cpu(int cpu)
{
return -ENODEV;
}
int __weak arch_register_cpu(int cpu)
{
return -ENODEV;
}
void __weak arch_unregister_cpu(int cpu) {}
static int acpi_processor_hotadd_init(struct acpi_processor *pr)
{
unsigned long long sta;
acpi_status status;
int ret;
if (invalid_phys_cpuid(pr->phys_id))
return -ENODEV;
status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
return -ENODEV;
cpu_maps_update_begin();
cpus_write_lock();
ret = acpi_map_cpu(pr->handle, pr->phys_id, pr->acpi_id, &pr->id);
if (ret)
goto out;
ret = arch_register_cpu(pr->id);
if (ret) {
acpi_unmap_cpu(pr->id);
goto out;
}
/*
* CPU got hot-added, but cpu_data is not initialized yet. Set a flag
* to delay cpu_idle/throttling initialization and do it when the CPU
* gets online for the first time.
*/
pr_info("CPU%d has been hot-added\n", pr->id);
pr->flags.need_hotplug_init = 1;
out:
cpus_write_unlock();
cpu_maps_update_done();
return ret;
}
#else
static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
{
return -ENODEV;
}
#endif /* CONFIG_ACPI_HOTPLUG_CPU */
static int acpi_processor_get_info(struct acpi_device *device)
{
union acpi_object object = { 0 };
struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
struct acpi_processor *pr = acpi_driver_data(device);
int device_declaration = 0;
acpi_status status = AE_OK;
static int cpu0_initialized;
unsigned long long value;
acpi_processor_errata();
/*
* Check to see if we have bus mastering arbitration control. This
* is required for proper C3 usage (to maintain cache coherency).
*/
if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
pr->flags.bm_control = 1;
dev_dbg(&device->dev, "Bus mastering arbitration control present\n");
} else
dev_dbg(&device->dev, "No bus mastering arbitration control\n");
if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
/* Declared with "Processor" statement; match ProcessorID */
status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
if (ACPI_FAILURE(status)) {
dev_err(&device->dev,
"Failed to evaluate processor object (0x%x)\n",
status);
return -ENODEV;
}
pr->acpi_id = object.processor.proc_id;
} else {
/*
* Declared with "Device" statement; match _UID.
*/
status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
NULL, &value);
if (ACPI_FAILURE(status)) {
dev_err(&device->dev,
"Failed to evaluate processor _UID (0x%x)\n",
status);
return -ENODEV;
}
device_declaration = 1;
pr->acpi_id = value;
}
if (acpi_duplicate_processor_id(pr->acpi_id)) {
if (pr->acpi_id == 0xff)
dev_info_once(&device->dev,
"Entry not well-defined, consider updating BIOS\n");
else
dev_err(&device->dev,
"Failed to get unique processor _UID (0x%x)\n",
pr->acpi_id);
return -ENODEV;
}
pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration,
pr->acpi_id);
if (invalid_phys_cpuid(pr->phys_id))
dev_dbg(&device->dev, "Failed to get CPU physical ID.\n");
pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
cpu0_initialized = 1;
/*
* Handle UP system running SMP kernel, with no CPU
* entry in MADT
*/
if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1))
pr->id = 0;
}
/*
* Extra Processor objects may be enumerated on MP systems with
* less than the max # of CPUs. They should be ignored _iff
* they are physically not present.
*
* NOTE: Even if the processor has a cpuid, it may not be present
* because cpuid <-> apicid mapping is persistent now.
*/
if (invalid_logical_cpuid(pr->id) || !cpu_present(pr->id)) {
int ret = acpi_processor_hotadd_init(pr);
if (ret)
return ret;
}
/*
* On some boxes several processors use the same processor bus id.
* But they are located in different scope. For example:
* \_SB.SCK0.CPU0
* \_SB.SCK1.CPU0
* Rename the processor device bus id. And the new bus id will be
* generated as the following format:
* CPU+CPU ID.
*/
sprintf(acpi_device_bid(device), "CPU%X", pr->id);
dev_dbg(&device->dev, "Processor [%d:%d]\n", pr->id, pr->acpi_id);
if (!object.processor.pblk_address)
dev_dbg(&device->dev, "No PBLK (NULL address)\n");
else if (object.processor.pblk_length != 6)
dev_err(&device->dev, "Invalid PBLK length [%d]\n",
object.processor.pblk_length);
else {
pr->throttling.address = object.processor.pblk_address;
pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
pr->pblk = object.processor.pblk_address;
}
/*
* If ACPI describes a slot number for this CPU, we can use it to
* ensure we get the right value in the "physical id" field
* of /proc/cpuinfo
*/
status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
if (ACPI_SUCCESS(status))
arch_fix_phys_package_id(pr->id, value);
return 0;
}
/*
* Do not put anything in here which needs the core to be online.
* For example MSR access or setting up things which check for cpuinfo_x86
* (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
* Such things have to be put in and set up by the processor driver's .probe().
*/
static DEFINE_PER_CPU(void *, processor_device_array);
static int acpi_processor_add(struct acpi_device *device,
const struct acpi_device_id *id)
{
struct acpi_processor *pr;
struct device *dev;
int result = 0;
pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
if (!pr)
return -ENOMEM;
if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
result = -ENOMEM;
goto err_free_pr;
}
pr->handle = device->handle;
strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
device->driver_data = pr;
result = acpi_processor_get_info(device);
if (result) /* Processor is not physically present or unavailable */
return 0;
BUG_ON(pr->id >= nr_cpu_ids);
/*
* Buggy BIOS check.
* ACPI id of processors can be reported wrongly by the BIOS.
* Don't trust it blindly
*/
if (per_cpu(processor_device_array, pr->id) != NULL &&
per_cpu(processor_device_array, pr->id) != device) {
dev_warn(&device->dev,
"BIOS reported wrong ACPI id %d for the processor\n",
pr->id);
/* Give up, but do not abort the namespace scan. */
goto err;
}
/*
* processor_device_array is not cleared on errors to allow buggy BIOS
* checks.
*/
per_cpu(processor_device_array, pr->id) = device;
per_cpu(processors, pr->id) = pr;
dev = get_cpu_device(pr->id);
if (!dev) {
result = -ENODEV;
goto err;
}
result = acpi_bind_one(dev, device);
if (result)
goto err;
pr->dev = dev;
/* Trigger the processor driver's .probe() if present. */
if (device_attach(dev) >= 0)
return 1;
dev_err(dev, "Processor driver could not be attached\n");
acpi_unbind_one(dev);
err:
free_cpumask_var(pr->throttling.shared_cpu_map);
device->driver_data = NULL;
per_cpu(processors, pr->id) = NULL;
err_free_pr:
kfree(pr);
return result;
}
#ifdef CONFIG_ACPI_HOTPLUG_CPU
/* Removal */
static void acpi_processor_remove(struct acpi_device *device)
{
struct acpi_processor *pr;
if (!device || !acpi_driver_data(device))
return;
pr = acpi_driver_data(device);
if (pr->id >= nr_cpu_ids)
goto out;
/*
* The only reason why we ever get here is CPU hot-removal. The CPU is
* already offline and the ACPI device removal locking prevents it from
* being put back online at this point.
*
* Unbind the driver from the processor device and detach it from the
* ACPI companion object.
*/
device_release_driver(pr->dev);
acpi_unbind_one(pr->dev);
/* Clean up. */
per_cpu(processor_device_array, pr->id) = NULL;
per_cpu(processors, pr->id) = NULL;
cpu_maps_update_begin();
cpus_write_lock();
/* Remove the CPU. */
arch_unregister_cpu(pr->id);
acpi_unmap_cpu(pr->id);
cpus_write_unlock();
cpu_maps_update_done();
try_offline_node(cpu_to_node(pr->id));
out:
free_cpumask_var(pr->throttling.shared_cpu_map);
kfree(pr);
}
#endif /* CONFIG_ACPI_HOTPLUG_CPU */
#ifdef CONFIG_X86
static bool acpi_hwp_native_thermal_lvt_set;
static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
u32 lvl,
void *context,
void **rv)
{
u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
u32 capbuf[2];
struct acpi_osc_context osc_context = {
.uuid_str = sb_uuid_str,
.rev = 1,
.cap.length = 8,
.cap.pointer = capbuf,
};
if (acpi_hwp_native_thermal_lvt_set)
return AE_CTRL_TERMINATE;
capbuf[0] = 0x0000;
capbuf[1] = 0x1000; /* set bit 12 */
if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
if (osc_context.ret.pointer && osc_context.ret.length > 1) {
u32 *capbuf_ret = osc_context.ret.pointer;
if (capbuf_ret[1] & 0x1000) {
acpi_handle_info(handle,
"_OSC native thermal LVT Acked\n");
acpi_hwp_native_thermal_lvt_set = true;
}
}
kfree(osc_context.ret.pointer);
}
return AE_OK;
}
void __init acpi_early_processor_osc(void)
{
if (boot_cpu_has(X86_FEATURE_HWP)) {
acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX,
acpi_hwp_native_thermal_lvt_osc,
NULL, NULL, NULL);
acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
acpi_hwp_native_thermal_lvt_osc,
NULL, NULL);
}
}
#endif
/*
* The following ACPI IDs are known to be suitable for representing as
* processor devices.
*/
static const struct acpi_device_id processor_device_ids[] = {
{ ACPI_PROCESSOR_OBJECT_HID, },
{ ACPI_PROCESSOR_DEVICE_HID, },
{ }
};
static struct acpi_scan_handler processor_handler = {
.ids = processor_device_ids,
.attach = acpi_processor_add,
#ifdef CONFIG_ACPI_HOTPLUG_CPU
.detach = acpi_processor_remove,
#endif
.hotplug = {
.enabled = true,
},
};
static int acpi_processor_container_attach(struct acpi_device *dev,
const struct acpi_device_id *id)
{
return 1;
}
static const struct acpi_device_id processor_container_ids[] = {
{ ACPI_PROCESSOR_CONTAINER_HID, },
{ }
};
static struct acpi_scan_handler processor_container_handler = {
.ids = processor_container_ids,
.attach = acpi_processor_container_attach,
};
/* The number of the unique processor IDs */
static int nr_unique_ids __initdata;
/* The number of the duplicate processor IDs */
static int nr_duplicate_ids;
/* Used to store the unique processor IDs */
static int unique_processor_ids[] __initdata = {
[0 ... NR_CPUS - 1] = -1,
};
/* Used to store the duplicate processor IDs */
static int duplicate_processor_ids[] = {
[0 ... NR_CPUS - 1] = -1,
};
static void __init processor_validated_ids_update(int proc_id)
{
int i;
if (nr_unique_ids == NR_CPUS||nr_duplicate_ids == NR_CPUS)
return;
/*
* Firstly, compare the proc_id with duplicate IDs, if the proc_id is
* already in the IDs, do nothing.
*/
for (i = 0; i < nr_duplicate_ids; i++) {
if (duplicate_processor_ids[i] == proc_id)
return;
}
/*
* Secondly, compare the proc_id with unique IDs, if the proc_id is in
* the IDs, put it in the duplicate IDs.
*/
for (i = 0; i < nr_unique_ids; i++) {
if (unique_processor_ids[i] == proc_id) {
duplicate_processor_ids[nr_duplicate_ids] = proc_id;
nr_duplicate_ids++;
return;
}
}
/*
* Lastly, the proc_id is a unique ID, put it in the unique IDs.
*/
unique_processor_ids[nr_unique_ids] = proc_id;
nr_unique_ids++;
}
static acpi_status __init acpi_processor_ids_walk(acpi_handle handle,
u32 lvl,
void *context,
void **rv)
{
acpi_status status;
acpi_object_type acpi_type;
unsigned long long uid;
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 status;
switch (acpi_type) {
case ACPI_TYPE_PROCESSOR:
status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
if (ACPI_FAILURE(status))
goto err;
uid = object.processor.proc_id;
break;
case ACPI_TYPE_DEVICE:
status = acpi_evaluate_integer(handle, "_UID", NULL, &uid);
if (ACPI_FAILURE(status))
goto err;
break;
default:
goto err;
}
processor_validated_ids_update(uid);
return AE_OK;
err:
/* Exit on error, but don't abort the namespace walk */
acpi_handle_info(handle, "Invalid processor object\n");
return AE_OK;
}
static void __init acpi_processor_check_duplicates(void)
{
/* check the correctness for all processors in ACPI namespace */
acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX,
acpi_processor_ids_walk,
NULL, NULL, NULL);
acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, acpi_processor_ids_walk,
NULL, NULL);
}
bool acpi_duplicate_processor_id(int proc_id)
{
int i;
/*
* compare the proc_id with duplicate IDs, if the proc_id is already
* in the duplicate IDs, return true, otherwise, return false.
*/
for (i = 0; i < nr_duplicate_ids; i++) {
if (duplicate_processor_ids[i] == proc_id)
return true;
}
return false;
}
void __init acpi_processor_init(void)
{
acpi_processor_check_duplicates();
acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
acpi_scan_add_handler(&processor_container_handler);
}
#ifdef CONFIG_ACPI_PROCESSOR_CSTATE
/**
* acpi_processor_claim_cst_control - Request _CST control from the platform.
*/
bool acpi_processor_claim_cst_control(void)
{
static bool cst_control_claimed;
acpi_status status;
if (!acpi_gbl_FADT.cst_control || cst_control_claimed)
return true;
status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
acpi_gbl_FADT.cst_control, 8);
if (ACPI_FAILURE(status)) {
pr_warn("ACPI: Failed to claim processor _CST control\n");
return false;
}
cst_control_claimed = true;
return true;
}
EXPORT_SYMBOL_GPL(acpi_processor_claim_cst_control);
/**
* acpi_processor_evaluate_cst - Evaluate the processor _CST control method.
* @handle: ACPI handle of the processor object containing the _CST.
* @cpu: The numeric ID of the target CPU.
* @info: Object write the C-states information into.
*
* Extract the C-state information for the given CPU from the output of the _CST
* control method under the corresponding ACPI processor object (or processor
* device object) and populate @info with it.
*
* If any ACPI_ADR_SPACE_FIXED_HARDWARE C-states are found, invoke
* acpi_processor_ffh_cstate_probe() to verify them and update the
* cpu_cstate_entry data for @cpu.
*/
int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
struct acpi_processor_power *info)
{
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *cst;
acpi_status status;
u64 count;
int last_index = 0;
int i, ret = 0;
status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
if (ACPI_FAILURE(status)) {
acpi_handle_debug(handle, "No _CST\n");
return -ENODEV;
}
cst = buffer.pointer;
/* There must be at least 2 elements. */
if (!cst || cst->type != ACPI_TYPE_PACKAGE || cst->package.count < 2) {
acpi_handle_warn(handle, "Invalid _CST output\n");
ret = -EFAULT;
goto end;
}
count = cst->package.elements[0].integer.value;
/* Validate the number of C-states. */
if (count < 1 || count != cst->package.count - 1) {
acpi_handle_warn(handle, "Inconsistent _CST data\n");
ret = -EFAULT;
goto end;
}
for (i = 1; i <= count; i++) {
union acpi_object *element;
union acpi_object *obj;
struct acpi_power_register *reg;
struct acpi_processor_cx cx;
/*
* If there is not enough space for all C-states, skip the
* excess ones and log a warning.
*/
if (last_index >= ACPI_PROCESSOR_MAX_POWER - 1) {
acpi_handle_warn(handle,
"No room for more idle states (limit: %d)\n",
ACPI_PROCESSOR_MAX_POWER - 1);
break;
}
memset(&cx, 0, sizeof(cx));
element = &cst->package.elements[i];
if (element->type != ACPI_TYPE_PACKAGE) {
acpi_handle_info(handle, "_CST C%d type(%x) is not package, skip...\n",
i, element->type);
continue;
}
if (element->package.count != 4) {
acpi_handle_info(handle, "_CST C%d package count(%d) is not 4, skip...\n",
i, element->package.count);
continue;
}
obj = &element->package.elements[0];
if (obj->type != ACPI_TYPE_BUFFER) {
acpi_handle_info(handle, "_CST C%d package element[0] type(%x) is not buffer, skip...\n",
i, obj->type);
continue;
}
reg = (struct acpi_power_register *)obj->buffer.pointer;
obj = &element->package.elements[1];
if (obj->type != ACPI_TYPE_INTEGER) {
acpi_handle_info(handle, "_CST C[%d] package element[1] type(%x) is not integer, skip...\n",
i, obj->type);
continue;
}
cx.type = obj->integer.value;
/*
* There are known cases in which the _CST output does not
* contain C1, so if the type of the first state found is not
* C1, leave an empty slot for C1 to be filled in later.
*/
if (i == 1 && cx.type != ACPI_STATE_C1)
last_index = 1;
cx.address = reg->address;
cx.index = last_index + 1;
if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) {
if (!acpi_processor_ffh_cstate_probe(cpu, &cx, reg)) {
/*
* In the majority of cases _CST describes C1 as
* a FIXED_HARDWARE C-state, but if the command
* line forbids using MWAIT, use CSTATE_HALT for
* C1 regardless.
*/
if (cx.type == ACPI_STATE_C1 &&
boot_option_idle_override == IDLE_NOMWAIT) {
cx.entry_method = ACPI_CSTATE_HALT;
snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
} else {
cx.entry_method = ACPI_CSTATE_FFH;
}
} else if (cx.type == ACPI_STATE_C1) {
/*
* In the special case of C1, FIXED_HARDWARE can
* be handled by executing the HLT instruction.
*/
cx.entry_method = ACPI_CSTATE_HALT;
snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI HLT");
} else {
acpi_handle_info(handle, "_CST C%d declares FIXED_HARDWARE C-state but not supported in hardware, skip...\n",
i);
continue;
}
} else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
cx.entry_method = ACPI_CSTATE_SYSTEMIO;
snprintf(cx.desc, ACPI_CX_DESC_LEN, "ACPI IOPORT 0x%x",
cx.address);
} else {
acpi_handle_info(handle, "_CST C%d space_id(%x) neither FIXED_HARDWARE nor SYSTEM_IO, skip...\n",
i, reg->space_id);
continue;
}
if (cx.type == ACPI_STATE_C1)
cx.valid = 1;
obj = &element->package.elements[2];
if (obj->type != ACPI_TYPE_INTEGER) {
acpi_handle_info(handle, "_CST C%d package element[2] type(%x) not integer, skip...\n",
i, obj->type);
continue;
}
cx.latency = obj->integer.value;
obj = &element->package.elements[3];
if (obj->type != ACPI_TYPE_INTEGER) {
acpi_handle_info(handle, "_CST C%d package element[3] type(%x) not integer, skip...\n",
i, obj->type);
continue;
}
memcpy(&info->states[++last_index], &cx, sizeof(cx));
}
acpi_handle_info(handle, "Found %d idle states\n", last_index);
info->count = last_index;
end:
kfree(buffer.pointer);
return ret;
}
EXPORT_SYMBOL_GPL(acpi_processor_evaluate_cst);
#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */