--- /dev/null
- *id = *id & MAX_ID_MASK;
+ /*
+ * 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;
+
++ *id = *id & MAX_IDR_MASK;
+ 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];
+ int ret = 0, i;
+ 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);
+ }
+ }
+ 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);
static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
int delay)
{
- cancel_delayed_work(&(tz->poll_queue));
-
- if (!delay)
- return;
-
if (delay > 1000)
- queue_delayed_work(system_freezable_wq, &(tz->poll_queue),
- round_jiffies(msecs_to_jiffies(delay)));
+ mod_delayed_work(system_freezable_wq, &tz->poll_queue,
+ round_jiffies(msecs_to_jiffies(delay)));
+ else if (delay)
+ mod_delayed_work(system_freezable_wq, &tz->poll_queue,
+ msecs_to_jiffies(delay));
else
- queue_delayed_work(system_freezable_wq, &(tz->poll_queue),
- msecs_to_jiffies(delay));
+ cancel_delayed_work(&tz->poll_queue);
}
- static void thermal_zone_device_passive(struct thermal_zone_device *tz,
- int temp, int trip_temp, int trip)
- {
- int trend = 0;
- struct thermal_cooling_device_instance *instance;
- struct thermal_cooling_device *cdev;
- long state, max_state;
-
- /*
- * Above Trip?
- * -----------
- * Calculate the thermal trend (using the passive cooling equation)
- * and modify the performance limit for all passive cooling devices
- * accordingly. Note that we assume symmetry.
- */
- if (temp >= trip_temp) {
- tz->passive = true;
-
- trend = (tz->tc1 * (temp - tz->last_temperature)) +
- (tz->tc2 * (temp - trip_temp));
-
- /* Heating up? */
- if (trend > 0) {
- list_for_each_entry(instance, &tz->cooling_devices,
- node) {
- if (instance->trip != trip)
- continue;
- cdev = instance->cdev;
- cdev->ops->get_cur_state(cdev, &state);
- cdev->ops->get_max_state(cdev, &max_state);
- if (state++ < max_state)
- cdev->ops->set_cur_state(cdev, state);
- }
- } else if (trend < 0) { /* Cooling off? */
- list_for_each_entry(instance, &tz->cooling_devices,
- node) {
- if (instance->trip != trip)
- continue;
- cdev = instance->cdev;
- cdev->ops->get_cur_state(cdev, &state);
- cdev->ops->get_max_state(cdev, &max_state);
- if (state > 0)
- cdev->ops->set_cur_state(cdev, --state);
- }
- }
- return;
- }
-
- /*
- * Below Trip?
- * -----------
- * Implement passive cooling hysteresis to slowly increase performance
- * and avoid thrashing around the passive trip point. Note that we
- * assume symmetry.
- */
- list_for_each_entry(instance, &tz->cooling_devices, node) {
- if (instance->trip != trip)
- continue;
- cdev = instance->cdev;
- cdev->ops->get_cur_state(cdev, &state);
- cdev->ops->get_max_state(cdev, &max_state);
- if (state > 0)
- cdev->ops->set_cur_state(cdev, --state);
- if (state == 0)
- tz->passive = false;
- }
- }
-
static void thermal_zone_device_check(struct work_struct *work)
{
struct thermal_zone_device *tz = container_of(work, struct
projects / linux-drm-fsl-dcu.git / commitdiff