2012-08-16 11:41:40 +00:00
|
|
|
/*
|
|
|
|
* linux/drivers/thermal/cpu_cooling.c
|
|
|
|
*
|
|
|
|
* Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com)
|
|
|
|
* Copyright (C) 2012 Amit Daniel <amit.kachhap@linaro.org>
|
|
|
|
*
|
|
|
|
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
* This program is free software; you can redistribute it and/or modify
|
|
|
|
* it under the terms of the GNU General Public License as published by
|
|
|
|
* the Free Software Foundation; version 2 of the License.
|
|
|
|
*
|
|
|
|
* This program is distributed in the hope that it will be useful, but
|
|
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
|
|
* General Public License for more details.
|
|
|
|
*
|
|
|
|
* You should have received a copy of the GNU General Public License along
|
|
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
|
|
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
|
|
|
|
*
|
|
|
|
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
|
|
#include <linux/module.h>
|
|
|
|
#include <linux/thermal.h>
|
|
|
|
#include <linux/platform_device.h>
|
|
|
|
#include <linux/cpufreq.h>
|
|
|
|
#include <linux/err.h>
|
|
|
|
#include <linux/slab.h>
|
|
|
|
#include <linux/cpu.h>
|
|
|
|
#include <linux/cpu_cooling.h>
|
|
|
|
|
|
|
|
/**
|
|
|
|
* struct cpufreq_cooling_device
|
|
|
|
* @id: unique integer value corresponding to each cpufreq_cooling_device
|
|
|
|
* registered.
|
|
|
|
* @cool_dev: thermal_cooling_device pointer to keep track of the the
|
|
|
|
* egistered cooling device.
|
|
|
|
* @cpufreq_state: integer value representing the current state of cpufreq
|
|
|
|
* cooling devices.
|
|
|
|
* @cpufreq_val: integer value representing the absolute value of the clipped
|
|
|
|
* frequency.
|
|
|
|
* @allowed_cpus: all the cpus involved for this cpufreq_cooling_device.
|
|
|
|
* @node: list_head to link all cpufreq_cooling_device together.
|
|
|
|
*
|
|
|
|
* This structure is required for keeping information of each
|
|
|
|
* cpufreq_cooling_device registered as a list whose head is represented by
|
|
|
|
* cooling_cpufreq_list. In order to prevent corruption of this list a
|
|
|
|
* mutex lock cooling_cpufreq_lock is used.
|
|
|
|
*/
|
|
|
|
struct cpufreq_cooling_device {
|
|
|
|
int id;
|
|
|
|
struct thermal_cooling_device *cool_dev;
|
|
|
|
unsigned int cpufreq_state;
|
|
|
|
unsigned int cpufreq_val;
|
|
|
|
struct cpumask allowed_cpus;
|
|
|
|
struct list_head node;
|
|
|
|
};
|
|
|
|
static LIST_HEAD(cooling_cpufreq_list);
|
|
|
|
static DEFINE_IDR(cpufreq_idr);
|
|
|
|
|
|
|
|
static struct mutex cooling_cpufreq_lock;
|
|
|
|
|
|
|
|
/* notify_table passes value to the CPUFREQ_ADJUST callback function. */
|
|
|
|
#define NOTIFY_INVALID NULL
|
|
|
|
struct cpufreq_cooling_device *notify_device;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* get_idr - function to get a unique id.
|
|
|
|
* @idr: struct idr * handle used to create a id.
|
|
|
|
* @id: int * value generated by this function.
|
|
|
|
*/
|
|
|
|
static int get_idr(struct idr *idr, int *id)
|
|
|
|
{
|
|
|
|
int err;
|
|
|
|
again:
|
|
|
|
if (unlikely(idr_pre_get(idr, GFP_KERNEL) == 0))
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
mutex_lock(&cooling_cpufreq_lock);
|
|
|
|
err = idr_get_new(idr, NULL, id);
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
|
|
|
|
if (unlikely(err == -EAGAIN))
|
|
|
|
goto again;
|
|
|
|
else if (unlikely(err))
|
|
|
|
return err;
|
|
|
|
|
2012-10-09 05:35:52 +00:00
|
|
|
*id = *id & MAX_IDR_MASK;
|
2012-08-16 11:41:40 +00:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* release_idr - function to free the unique id.
|
|
|
|
* @idr: struct idr * handle used for creating the id.
|
|
|
|
* @id: int value representing the unique id.
|
|
|
|
*/
|
|
|
|
static void release_idr(struct idr *idr, int id)
|
|
|
|
{
|
|
|
|
mutex_lock(&cooling_cpufreq_lock);
|
|
|
|
idr_remove(idr, id);
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Below code defines functions to be used for cpufreq as cooling device */
|
|
|
|
|
|
|
|
/**
|
|
|
|
* is_cpufreq_valid - function to check if a cpu has frequency transition policy.
|
|
|
|
* @cpu: cpu for which check is needed.
|
|
|
|
*/
|
|
|
|
static int is_cpufreq_valid(int cpu)
|
|
|
|
{
|
|
|
|
struct cpufreq_policy policy;
|
|
|
|
return !cpufreq_get_policy(&policy, cpu);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* get_cpu_frequency - get the absolute value of frequency from level.
|
|
|
|
* @cpu: cpu for which frequency is fetched.
|
|
|
|
* @level: level of frequency of the CPU
|
|
|
|
* e.g level=1 --> 1st MAX FREQ, LEVEL=2 ---> 2nd MAX FREQ, .... etc
|
|
|
|
*/
|
|
|
|
static unsigned int get_cpu_frequency(unsigned int cpu, unsigned long level)
|
|
|
|
{
|
|
|
|
int ret = 0, i = 0;
|
|
|
|
unsigned long level_index;
|
|
|
|
bool descend = false;
|
|
|
|
struct cpufreq_frequency_table *table =
|
|
|
|
cpufreq_frequency_get_table(cpu);
|
|
|
|
if (!table)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
while (table[i].frequency != CPUFREQ_TABLE_END) {
|
|
|
|
if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
/*check if table in ascending or descending order*/
|
|
|
|
if ((table[i + 1].frequency != CPUFREQ_TABLE_END) &&
|
|
|
|
(table[i + 1].frequency < table[i].frequency)
|
|
|
|
&& !descend) {
|
|
|
|
descend = true;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*return if level matched and table in descending order*/
|
|
|
|
if (descend && i == level)
|
|
|
|
return table[i].frequency;
|
|
|
|
i++;
|
|
|
|
}
|
|
|
|
i--;
|
|
|
|
|
|
|
|
if (level > i || descend)
|
|
|
|
return ret;
|
|
|
|
level_index = i - level;
|
|
|
|
|
|
|
|
/*Scan the table in reverse order and match the level*/
|
|
|
|
while (i >= 0) {
|
|
|
|
if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
|
|
|
|
continue;
|
|
|
|
/*return if level matched*/
|
|
|
|
if (i == level_index)
|
|
|
|
return table[i].frequency;
|
|
|
|
i--;
|
|
|
|
}
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* cpufreq_apply_cooling - function to apply frequency clipping.
|
|
|
|
* @cpufreq_device: cpufreq_cooling_device pointer containing frequency
|
|
|
|
* clipping data.
|
|
|
|
* @cooling_state: value of the cooling state.
|
|
|
|
*/
|
|
|
|
static int cpufreq_apply_cooling(struct cpufreq_cooling_device *cpufreq_device,
|
|
|
|
unsigned long cooling_state)
|
|
|
|
{
|
|
|
|
unsigned int cpuid, clip_freq;
|
|
|
|
struct cpumask *maskPtr = &cpufreq_device->allowed_cpus;
|
|
|
|
unsigned int cpu = cpumask_any(maskPtr);
|
|
|
|
|
|
|
|
|
|
|
|
/* Check if the old cooling action is same as new cooling action */
|
|
|
|
if (cpufreq_device->cpufreq_state == cooling_state)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
clip_freq = get_cpu_frequency(cpu, cooling_state);
|
|
|
|
if (!clip_freq)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
cpufreq_device->cpufreq_state = cooling_state;
|
|
|
|
cpufreq_device->cpufreq_val = clip_freq;
|
|
|
|
notify_device = cpufreq_device;
|
|
|
|
|
|
|
|
for_each_cpu(cpuid, maskPtr) {
|
|
|
|
if (is_cpufreq_valid(cpuid))
|
|
|
|
cpufreq_update_policy(cpuid);
|
|
|
|
}
|
|
|
|
|
|
|
|
notify_device = NOTIFY_INVALID;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* cpufreq_thermal_notifier - notifier callback for cpufreq policy change.
|
|
|
|
* @nb: struct notifier_block * with callback info.
|
|
|
|
* @event: value showing cpufreq event for which this function invoked.
|
|
|
|
* @data: callback-specific data
|
|
|
|
*/
|
|
|
|
static int cpufreq_thermal_notifier(struct notifier_block *nb,
|
|
|
|
unsigned long event, void *data)
|
|
|
|
{
|
|
|
|
struct cpufreq_policy *policy = data;
|
|
|
|
unsigned long max_freq = 0;
|
|
|
|
|
|
|
|
if (event != CPUFREQ_ADJUST || notify_device == NOTIFY_INVALID)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
if (cpumask_test_cpu(policy->cpu, ¬ify_device->allowed_cpus))
|
|
|
|
max_freq = notify_device->cpufreq_val;
|
|
|
|
|
|
|
|
/* Never exceed user_policy.max*/
|
|
|
|
if (max_freq > policy->user_policy.max)
|
|
|
|
max_freq = policy->user_policy.max;
|
|
|
|
|
|
|
|
if (policy->max != max_freq)
|
|
|
|
cpufreq_verify_within_limits(policy, 0, max_freq);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* cpufreq cooling device callback functions are defined below
|
|
|
|
*/
|
|
|
|
|
|
|
|
/**
|
|
|
|
* cpufreq_get_max_state - callback function to get the max cooling state.
|
|
|
|
* @cdev: thermal cooling device pointer.
|
|
|
|
* @state: fill this variable with the max cooling state.
|
|
|
|
*/
|
|
|
|
static int cpufreq_get_max_state(struct thermal_cooling_device *cdev,
|
|
|
|
unsigned long *state)
|
|
|
|
{
|
|
|
|
int ret = -EINVAL, i = 0;
|
|
|
|
struct cpufreq_cooling_device *cpufreq_device;
|
|
|
|
struct cpumask *maskPtr;
|
|
|
|
unsigned int cpu;
|
|
|
|
struct cpufreq_frequency_table *table;
|
|
|
|
|
|
|
|
mutex_lock(&cooling_cpufreq_lock);
|
|
|
|
list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
|
|
|
|
if (cpufreq_device && cpufreq_device->cool_dev == cdev)
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
if (cpufreq_device == NULL)
|
|
|
|
goto return_get_max_state;
|
|
|
|
|
|
|
|
maskPtr = &cpufreq_device->allowed_cpus;
|
|
|
|
cpu = cpumask_any(maskPtr);
|
|
|
|
table = cpufreq_frequency_get_table(cpu);
|
|
|
|
if (!table) {
|
|
|
|
*state = 0;
|
|
|
|
ret = 0;
|
|
|
|
goto return_get_max_state;
|
|
|
|
}
|
|
|
|
|
|
|
|
while (table[i].frequency != CPUFREQ_TABLE_END) {
|
|
|
|
if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
|
|
|
|
continue;
|
|
|
|
i++;
|
|
|
|
}
|
|
|
|
if (i > 0) {
|
|
|
|
*state = --i;
|
|
|
|
ret = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
return_get_max_state:
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* cpufreq_get_cur_state - callback function to get the current cooling state.
|
|
|
|
* @cdev: thermal cooling device pointer.
|
|
|
|
* @state: fill this variable with the current cooling state.
|
|
|
|
*/
|
|
|
|
static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev,
|
|
|
|
unsigned long *state)
|
|
|
|
{
|
|
|
|
int ret = -EINVAL;
|
|
|
|
struct cpufreq_cooling_device *cpufreq_device;
|
|
|
|
|
|
|
|
mutex_lock(&cooling_cpufreq_lock);
|
|
|
|
list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
|
|
|
|
if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
|
|
|
|
*state = cpufreq_device->cpufreq_state;
|
|
|
|
ret = 0;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* cpufreq_set_cur_state - callback function to set the current cooling state.
|
|
|
|
* @cdev: thermal cooling device pointer.
|
|
|
|
* @state: set this variable to the current cooling state.
|
|
|
|
*/
|
|
|
|
static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev,
|
|
|
|
unsigned long state)
|
|
|
|
{
|
|
|
|
int ret = -EINVAL;
|
|
|
|
struct cpufreq_cooling_device *cpufreq_device;
|
|
|
|
|
|
|
|
mutex_lock(&cooling_cpufreq_lock);
|
|
|
|
list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) {
|
|
|
|
if (cpufreq_device && cpufreq_device->cool_dev == cdev) {
|
|
|
|
ret = 0;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
if (!ret)
|
|
|
|
ret = cpufreq_apply_cooling(cpufreq_device, state);
|
|
|
|
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Bind cpufreq callbacks to thermal cooling device ops */
|
|
|
|
static struct thermal_cooling_device_ops const cpufreq_cooling_ops = {
|
|
|
|
.get_max_state = cpufreq_get_max_state,
|
|
|
|
.get_cur_state = cpufreq_get_cur_state,
|
|
|
|
.set_cur_state = cpufreq_set_cur_state,
|
|
|
|
};
|
|
|
|
|
|
|
|
/* Notifier for cpufreq policy change */
|
|
|
|
static struct notifier_block thermal_cpufreq_notifier_block = {
|
|
|
|
.notifier_call = cpufreq_thermal_notifier,
|
|
|
|
};
|
|
|
|
|
|
|
|
/**
|
|
|
|
* cpufreq_cooling_register - function to create cpufreq cooling device.
|
|
|
|
* @clip_cpus: cpumask of cpus where the frequency constraints will happen.
|
|
|
|
*/
|
|
|
|
struct thermal_cooling_device *cpufreq_cooling_register(
|
|
|
|
struct cpumask *clip_cpus)
|
|
|
|
{
|
|
|
|
struct thermal_cooling_device *cool_dev;
|
|
|
|
struct cpufreq_cooling_device *cpufreq_dev = NULL;
|
|
|
|
unsigned int cpufreq_dev_count = 0, min = 0, max = 0;
|
|
|
|
char dev_name[THERMAL_NAME_LENGTH];
|
2012-09-26 00:43:31 +00:00
|
|
|
int ret = 0, i;
|
2012-08-16 11:41:40 +00:00
|
|
|
struct cpufreq_policy policy;
|
|
|
|
|
|
|
|
list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node)
|
|
|
|
cpufreq_dev_count++;
|
|
|
|
|
|
|
|
/*Verify that all the clip cpus have same freq_min, freq_max limit*/
|
|
|
|
for_each_cpu(i, clip_cpus) {
|
|
|
|
/*continue if cpufreq policy not found and not return error*/
|
|
|
|
if (!cpufreq_get_policy(&policy, i))
|
|
|
|
continue;
|
|
|
|
if (min == 0 && max == 0) {
|
|
|
|
min = policy.cpuinfo.min_freq;
|
|
|
|
max = policy.cpuinfo.max_freq;
|
|
|
|
} else {
|
|
|
|
if (min != policy.cpuinfo.min_freq ||
|
|
|
|
max != policy.cpuinfo.max_freq)
|
|
|
|
return ERR_PTR(-EINVAL);
|
2012-10-30 16:48:57 +00:00
|
|
|
}
|
2012-08-16 11:41:40 +00:00
|
|
|
}
|
|
|
|
cpufreq_dev = kzalloc(sizeof(struct cpufreq_cooling_device),
|
|
|
|
GFP_KERNEL);
|
|
|
|
if (!cpufreq_dev)
|
|
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
|
|
|
|
cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus);
|
|
|
|
|
|
|
|
if (cpufreq_dev_count == 0)
|
|
|
|
mutex_init(&cooling_cpufreq_lock);
|
|
|
|
|
|
|
|
ret = get_idr(&cpufreq_idr, &cpufreq_dev->id);
|
|
|
|
if (ret) {
|
|
|
|
kfree(cpufreq_dev);
|
|
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
}
|
|
|
|
|
|
|
|
sprintf(dev_name, "thermal-cpufreq-%d", cpufreq_dev->id);
|
|
|
|
|
|
|
|
cool_dev = thermal_cooling_device_register(dev_name, cpufreq_dev,
|
|
|
|
&cpufreq_cooling_ops);
|
|
|
|
if (!cool_dev) {
|
|
|
|
release_idr(&cpufreq_idr, cpufreq_dev->id);
|
|
|
|
kfree(cpufreq_dev);
|
|
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
}
|
|
|
|
cpufreq_dev->cool_dev = cool_dev;
|
|
|
|
cpufreq_dev->cpufreq_state = 0;
|
|
|
|
mutex_lock(&cooling_cpufreq_lock);
|
|
|
|
list_add_tail(&cpufreq_dev->node, &cooling_cpufreq_list);
|
|
|
|
|
|
|
|
/* Register the notifier for first cpufreq cooling device */
|
|
|
|
if (cpufreq_dev_count == 0)
|
|
|
|
cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
|
|
|
|
CPUFREQ_POLICY_NOTIFIER);
|
|
|
|
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
return cool_dev;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(cpufreq_cooling_register);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* cpufreq_cooling_unregister - function to remove cpufreq cooling device.
|
|
|
|
* @cdev: thermal cooling device pointer.
|
|
|
|
*/
|
|
|
|
void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
|
|
|
|
{
|
|
|
|
struct cpufreq_cooling_device *cpufreq_dev = NULL;
|
|
|
|
unsigned int cpufreq_dev_count = 0;
|
|
|
|
|
|
|
|
mutex_lock(&cooling_cpufreq_lock);
|
|
|
|
list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node) {
|
|
|
|
if (cpufreq_dev && cpufreq_dev->cool_dev == cdev)
|
|
|
|
break;
|
|
|
|
cpufreq_dev_count++;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (!cpufreq_dev || cpufreq_dev->cool_dev != cdev) {
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
list_del(&cpufreq_dev->node);
|
|
|
|
|
|
|
|
/* Unregister the notifier for the last cpufreq cooling device */
|
|
|
|
if (cpufreq_dev_count == 1) {
|
|
|
|
cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block,
|
|
|
|
CPUFREQ_POLICY_NOTIFIER);
|
|
|
|
}
|
|
|
|
mutex_unlock(&cooling_cpufreq_lock);
|
|
|
|
thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
|
|
|
|
release_idr(&cpufreq_idr, cpufreq_dev->id);
|
|
|
|
if (cpufreq_dev_count == 1)
|
|
|
|
mutex_destroy(&cooling_cpufreq_lock);
|
|
|
|
kfree(cpufreq_dev);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(cpufreq_cooling_unregister);
|