ACPI: register ACPI Processor as generic thermal cooling device

Register ACPI processor as thermal cooling devices.
A combination of processor T-state and P-state are used for thermal throttling.
the processor will reduce the frequency first and then set the T-state.

we use cpufreq_thermal_reduction_pctg to calculate the cpufreq limit,
and call cpufreq_verify_with_limit to set the cpufreq limit.
if cpufreq driver is loaded, then we have four cooling state for cpufreq control.
cooling state 0: cpufreq limit == max_freq
cooling state 1: cpufreq limit == max_freq * 80%
cooling state 2: cpufreq limit == max_freq * 60%
cooling state 3: cpufreq limit == max_freq * 40%

after the cpufreq limit is set to 40 percentage of the max_freq,
we use T-state for cooling.

eg. a processor has P-state support, and it has 8 T-state (T0-T7),
the max_state of the proceesor is 10:

state	cpufreq-limit  T-state
0:	max_freq	T0
1:	max_freq * 80%	T0
2:	max_freq * 60%	T0
3:	max_freq * 40%	T0
4:	max_freq * 40%	T1
5:	max_freq * 40%	T2
6:	max_freq * 40%	T3
7:	max_freq * 40%	T4
8:	max_freq * 40%	T5
9:	max_freq * 40%	T6
10:	max_freq * 40%	T7

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Thomas Sujith <sujith.thomas@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This commit is contained in:
Zhang Rui 2008-01-17 15:51:23 +08:00 committed by Len Brown
parent 05a83d9722
commit d9460fd227
3 changed files with 155 additions and 8 deletions

View file

@ -668,6 +668,24 @@ static int __cpuinit acpi_processor_start(struct acpi_device *device)
acpi_processor_power_init(pr, device);
pr->cdev = thermal_cooling_device_register("Processor", device,
&processor_cooling_ops);
if (pr->cdev)
printk(KERN_INFO PREFIX
"%s is registered as cooling_device%d\n",
device->dev.bus_id, pr->cdev->id);
else
goto end;
result = sysfs_create_link(&device->dev.kobj, &pr->cdev->device.kobj,
"thermal_cooling");
if (result)
return result;
result = sysfs_create_link(&pr->cdev->device.kobj, &device->dev.kobj,
"device");
if (result)
return result;
if (pr->flags.throttling) {
printk(KERN_INFO PREFIX "%s [%s] (supports",
acpi_device_name(device), acpi_device_bid(device));
@ -791,6 +809,11 @@ static int acpi_processor_remove(struct acpi_device *device, int type)
acpi_processor_remove_fs(device);
sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
sysfs_remove_link(&pr->cdev->device.kobj, "device");
thermal_cooling_device_unregister(pr->cdev);
pr->cdev = NULL;
processors[pr->id] = NULL;
kfree(pr);

View file

@ -32,6 +32,7 @@
#include <linux/cpufreq.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/sysdev.h>
#include <asm/uaccess.h>
@ -93,6 +94,9 @@ static int acpi_processor_apply_limit(struct acpi_processor *pr)
* _any_ cpufreq driver and not only the acpi-cpufreq driver.
*/
#define CPUFREQ_THERMAL_MIN_STEP 0
#define CPUFREQ_THERMAL_MAX_STEP 3
static unsigned int cpufreq_thermal_reduction_pctg[NR_CPUS];
static unsigned int acpi_thermal_cpufreq_is_init = 0;
@ -109,8 +113,9 @@ static int acpi_thermal_cpufreq_increase(unsigned int cpu)
if (!cpu_has_cpufreq(cpu))
return -ENODEV;
if (cpufreq_thermal_reduction_pctg[cpu] < 60) {
cpufreq_thermal_reduction_pctg[cpu] += 20;
if (cpufreq_thermal_reduction_pctg[cpu] <
CPUFREQ_THERMAL_MAX_STEP) {
cpufreq_thermal_reduction_pctg[cpu]++;
cpufreq_update_policy(cpu);
return 0;
}
@ -123,8 +128,9 @@ static int acpi_thermal_cpufreq_decrease(unsigned int cpu)
if (!cpu_has_cpufreq(cpu))
return -ENODEV;
if (cpufreq_thermal_reduction_pctg[cpu] > 20)
cpufreq_thermal_reduction_pctg[cpu] -= 20;
if (cpufreq_thermal_reduction_pctg[cpu] >
(CPUFREQ_THERMAL_MIN_STEP + 1))
cpufreq_thermal_reduction_pctg[cpu]--;
else
cpufreq_thermal_reduction_pctg[cpu] = 0;
cpufreq_update_policy(cpu);
@ -143,7 +149,7 @@ static int acpi_thermal_cpufreq_notifier(struct notifier_block *nb,
max_freq =
(policy->cpuinfo.max_freq *
(100 - cpufreq_thermal_reduction_pctg[policy->cpu])) / 100;
(100 - cpufreq_thermal_reduction_pctg[policy->cpu] * 20)) / 100;
cpufreq_verify_within_limits(policy, 0, max_freq);
@ -155,6 +161,32 @@ static struct notifier_block acpi_thermal_cpufreq_notifier_block = {
.notifier_call = acpi_thermal_cpufreq_notifier,
};
static int cpufreq_get_max_state(unsigned int cpu)
{
if (!cpu_has_cpufreq(cpu))
return 0;
return CPUFREQ_THERMAL_MAX_STEP;
}
static int cpufreq_get_cur_state(unsigned int cpu)
{
if (!cpu_has_cpufreq(cpu))
return 0;
return cpufreq_thermal_reduction_pctg[cpu];
}
static int cpufreq_set_cur_state(unsigned int cpu, int state)
{
if (!cpu_has_cpufreq(cpu))
return 0;
cpufreq_thermal_reduction_pctg[cpu] = state;
cpufreq_update_policy(cpu);
return 0;
}
void acpi_thermal_cpufreq_init(void)
{
int i;
@ -179,6 +211,20 @@ void acpi_thermal_cpufreq_exit(void)
}
#else /* ! CONFIG_CPU_FREQ */
static int cpufreq_get_max_state(unsigned int cpu)
{
return 0;
}
static int cpufreq_get_cur_state(unsigned int cpu)
{
return 0;
}
static int cpufreq_set_cur_state(unsigned int cpu, int state)
{
return 0;
}
static int acpi_thermal_cpufreq_increase(unsigned int cpu)
{
@ -310,6 +356,84 @@ int acpi_processor_get_limit_info(struct acpi_processor *pr)
return 0;
}
/* thermal coolign device callbacks */
static int acpi_processor_max_state(struct acpi_processor *pr)
{
int max_state = 0;
/*
* There exists four states according to
* cpufreq_thermal_reduction_ptg. 0, 1, 2, 3
*/
max_state += cpufreq_get_max_state(pr->id);
if (pr->flags.throttling)
max_state += (pr->throttling.state_count -1);
return max_state;
}
static int
processor_get_max_state(struct thermal_cooling_device *cdev, char *buf)
{
struct acpi_device *device = cdev->devdata;
struct acpi_processor *pr = acpi_driver_data(device);
if (!device || !pr)
return -EINVAL;
return sprintf(buf, "%d\n", acpi_processor_max_state(pr));
}
static int
processor_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
{
struct acpi_device *device = cdev->devdata;
struct acpi_processor *pr = acpi_driver_data(device);
int cur_state;
if (!device || !pr)
return -EINVAL;
cur_state = cpufreq_get_cur_state(pr->id);
if (pr->flags.throttling)
cur_state += pr->throttling.state;
return sprintf(buf, "%d\n", cur_state);
}
static int
processor_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
{
struct acpi_device *device = cdev->devdata;
struct acpi_processor *pr = acpi_driver_data(device);
int result = 0;
int max_pstate;
if (!device || !pr)
return -EINVAL;
max_pstate = cpufreq_get_max_state(pr->id);
if (state > acpi_processor_max_state(pr))
return -EINVAL;
if (state <= max_pstate) {
if (pr->flags.throttling && pr->throttling.state)
result = acpi_processor_set_throttling(pr, 0);
cpufreq_set_cur_state(pr->id, state);
} else {
cpufreq_set_cur_state(pr->id, max_pstate);
result = acpi_processor_set_throttling(pr,
state - max_pstate);
}
return result;
}
struct thermal_cooling_device_ops processor_cooling_ops = {
.get_max_state = processor_get_max_state,
.get_cur_state = processor_get_cur_state,
.set_cur_state = processor_set_cur_state,
};
/* /proc interface */
static int acpi_processor_limit_seq_show(struct seq_file *seq, void *offset)

View file

@ -4,7 +4,7 @@
#include <linux/kernel.h>
#include <linux/cpu.h>
#include <linux/cpuidle.h>
#include <linux/thermal.h>
#include <asm/acpi.h>
#define ACPI_PROCESSOR_BUSY_METRIC 10
@ -218,7 +218,7 @@ struct acpi_processor {
struct acpi_processor_performance *performance;
struct acpi_processor_throttling throttling;
struct acpi_processor_limit limit;
struct thermal_cooling_device *cdev;
/* the _PDC objects for this processor, if any */
struct acpi_object_list *pdc;
};
@ -330,7 +330,7 @@ extern struct cpuidle_driver acpi_idle_driver;
/* in processor_thermal.c */
int acpi_processor_get_limit_info(struct acpi_processor *pr);
extern struct file_operations acpi_processor_limit_fops;
extern struct thermal_cooling_device_ops processor_cooling_ops;
#ifdef CONFIG_CPU_FREQ
void acpi_thermal_cpufreq_init(void);
void acpi_thermal_cpufreq_exit(void);