aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/devfreq/devfreq.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/devfreq/devfreq.c')
-rw-r--r--drivers/devfreq/devfreq.c439
1 files changed, 345 insertions, 94 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 425149e8bab0..cceee8bc3c2f 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -10,6 +10,7 @@
#include <linux/kernel.h>
#include <linux/kmod.h>
#include <linux/sched.h>
+#include <linux/debugfs.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/init.h>
@@ -24,12 +25,16 @@
#include <linux/printk.h>
#include <linux/hrtimer.h>
#include <linux/of.h>
+#include <linux/pm_qos.h>
#include "governor.h"
#define CREATE_TRACE_POINTS
#include <trace/events/devfreq.h>
+#define HZ_PER_KHZ 1000
+
static struct class *devfreq_class;
+static struct dentry *devfreq_debugfs;
/*
* devfreq core provides delayed work based load monitoring helper
@@ -99,6 +104,54 @@ static unsigned long find_available_max_freq(struct devfreq *devfreq)
}
/**
+ * get_freq_range() - Get the current freq range
+ * @devfreq: the devfreq instance
+ * @min_freq: the min frequency
+ * @max_freq: the max frequency
+ *
+ * This takes into consideration all constraints.
+ */
+static void get_freq_range(struct devfreq *devfreq,
+ unsigned long *min_freq,
+ unsigned long *max_freq)
+{
+ unsigned long *freq_table = devfreq->profile->freq_table;
+ s32 qos_min_freq, qos_max_freq;
+
+ lockdep_assert_held(&devfreq->lock);
+
+ /*
+ * Initialize minimum/maximum frequency from freq table.
+ * The devfreq drivers can initialize this in either ascending or
+ * descending order and devfreq core supports both.
+ */
+ if (freq_table[0] < freq_table[devfreq->profile->max_state - 1]) {
+ *min_freq = freq_table[0];
+ *max_freq = freq_table[devfreq->profile->max_state - 1];
+ } else {
+ *min_freq = freq_table[devfreq->profile->max_state - 1];
+ *max_freq = freq_table[0];
+ }
+
+ /* Apply constraints from PM QoS */
+ qos_min_freq = dev_pm_qos_read_value(devfreq->dev.parent,
+ DEV_PM_QOS_MIN_FREQUENCY);
+ qos_max_freq = dev_pm_qos_read_value(devfreq->dev.parent,
+ DEV_PM_QOS_MAX_FREQUENCY);
+ *min_freq = max(*min_freq, (unsigned long)HZ_PER_KHZ * qos_min_freq);
+ if (qos_max_freq != PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE)
+ *max_freq = min(*max_freq,
+ (unsigned long)HZ_PER_KHZ * qos_max_freq);
+
+ /* Apply constraints from OPP interface */
+ *min_freq = max(*min_freq, devfreq->scaling_min_freq);
+ *max_freq = min(*max_freq, devfreq->scaling_max_freq);
+
+ if (*min_freq > *max_freq)
+ *min_freq = *max_freq;
+}
+
+/**
* devfreq_get_freq_level() - Lookup freq_table for the frequency
* @devfreq: the devfreq instance
* @freq: the target frequency
@@ -158,10 +211,10 @@ static int set_freq_table(struct devfreq *devfreq)
int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
{
int lev, prev_lev, ret = 0;
- unsigned long cur_time;
+ u64 cur_time;
lockdep_assert_held(&devfreq->lock);
- cur_time = jiffies;
+ cur_time = get_jiffies_64();
/* Immediately exit if previous_freq is not initialized yet. */
if (!devfreq->previous_freq)
@@ -173,8 +226,8 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
goto out;
}
- devfreq->time_in_state[prev_lev] +=
- cur_time - devfreq->last_stat_updated;
+ devfreq->stats.time_in_state[prev_lev] +=
+ cur_time - devfreq->stats.last_update;
lev = devfreq_get_freq_level(devfreq, freq);
if (lev < 0) {
@@ -183,13 +236,13 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
}
if (lev != prev_lev) {
- devfreq->trans_table[(prev_lev *
- devfreq->profile->max_state) + lev]++;
- devfreq->total_trans++;
+ devfreq->stats.trans_table[
+ (prev_lev * devfreq->profile->max_state) + lev]++;
+ devfreq->stats.total_trans++;
}
out:
- devfreq->last_stat_updated = cur_time;
+ devfreq->stats.last_update = cur_time;
return ret;
}
EXPORT_SYMBOL(devfreq_update_status);
@@ -351,16 +404,7 @@ int update_devfreq(struct devfreq *devfreq)
err = devfreq->governor->get_target_freq(devfreq, &freq);
if (err)
return err;
-
- /*
- * Adjust the frequency with user freq, QoS and available freq.
- *
- * List from the highest priority
- * max_freq
- * min_freq
- */
- max_freq = min(devfreq->scaling_max_freq, devfreq->max_freq);
- min_freq = max(devfreq->scaling_min_freq, devfreq->min_freq);
+ get_freq_range(devfreq, &min_freq, &max_freq);
if (freq < min_freq) {
freq = min_freq;
@@ -493,7 +537,7 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
msecs_to_jiffies(devfreq->profile->polling_ms));
out_update:
- devfreq->last_stat_updated = jiffies;
+ devfreq->stats.last_update = get_jiffies_64();
devfreq->stop_polling = false;
if (devfreq->profile->get_cur_freq &&
@@ -568,26 +612,69 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type,
void *devp)
{
struct devfreq *devfreq = container_of(nb, struct devfreq, nb);
- int ret;
+ int err = -EINVAL;
mutex_lock(&devfreq->lock);
devfreq->scaling_min_freq = find_available_min_freq(devfreq);
- if (!devfreq->scaling_min_freq) {
- mutex_unlock(&devfreq->lock);
- return -EINVAL;
- }
+ if (!devfreq->scaling_min_freq)
+ goto out;
devfreq->scaling_max_freq = find_available_max_freq(devfreq);
if (!devfreq->scaling_max_freq) {
- mutex_unlock(&devfreq->lock);
- return -EINVAL;
+ devfreq->scaling_max_freq = ULONG_MAX;
+ goto out;
}
- ret = update_devfreq(devfreq);
+ err = update_devfreq(devfreq);
+
+out:
mutex_unlock(&devfreq->lock);
+ if (err)
+ dev_err(devfreq->dev.parent,
+ "failed to update frequency from OPP notifier (%d)\n",
+ err);
- return ret;
+ return NOTIFY_OK;
+}
+
+/**
+ * qos_notifier_call() - Common handler for QoS constraints.
+ * @devfreq: the devfreq instance.
+ */
+static int qos_notifier_call(struct devfreq *devfreq)
+{
+ int err;
+
+ mutex_lock(&devfreq->lock);
+ err = update_devfreq(devfreq);
+ mutex_unlock(&devfreq->lock);
+ if (err)
+ dev_err(devfreq->dev.parent,
+ "failed to update frequency from PM QoS (%d)\n",
+ err);
+
+ return NOTIFY_OK;
+}
+
+/**
+ * qos_min_notifier_call() - Callback for QoS min_freq changes.
+ * @nb: Should be devfreq->nb_min
+ */
+static int qos_min_notifier_call(struct notifier_block *nb,
+ unsigned long val, void *ptr)
+{
+ return qos_notifier_call(container_of(nb, struct devfreq, nb_min));
+}
+
+/**
+ * qos_max_notifier_call() - Callback for QoS max_freq changes.
+ * @nb: Should be devfreq->nb_max
+ */
+static int qos_max_notifier_call(struct notifier_block *nb,
+ unsigned long val, void *ptr)
+{
+ return qos_notifier_call(container_of(nb, struct devfreq, nb_max));
}
/**
@@ -599,16 +686,36 @@ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type,
static void devfreq_dev_release(struct device *dev)
{
struct devfreq *devfreq = to_devfreq(dev);
+ int err;
mutex_lock(&devfreq_list_lock);
- if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) {
- mutex_unlock(&devfreq_list_lock);
- dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n");
- return;
- }
list_del(&devfreq->node);
mutex_unlock(&devfreq_list_lock);
+ err = dev_pm_qos_remove_notifier(devfreq->dev.parent, &devfreq->nb_max,
+ DEV_PM_QOS_MAX_FREQUENCY);
+ if (err && err != -ENOENT)
+ dev_warn(dev->parent,
+ "Failed to remove max_freq notifier: %d\n", err);
+ err = dev_pm_qos_remove_notifier(devfreq->dev.parent, &devfreq->nb_min,
+ DEV_PM_QOS_MIN_FREQUENCY);
+ if (err && err != -ENOENT)
+ dev_warn(dev->parent,
+ "Failed to remove min_freq notifier: %d\n", err);
+
+ if (dev_pm_qos_request_active(&devfreq->user_max_freq_req)) {
+ err = dev_pm_qos_remove_request(&devfreq->user_max_freq_req);
+ if (err)
+ dev_warn(dev->parent,
+ "Failed to remove max_freq request: %d\n", err);
+ }
+ if (dev_pm_qos_request_active(&devfreq->user_min_freq_req)) {
+ err = dev_pm_qos_remove_request(&devfreq->user_min_freq_req);
+ if (err)
+ dev_warn(dev->parent,
+ "Failed to remove min_freq request: %d\n", err);
+ }
+
if (devfreq->profile->exit)
devfreq->profile->exit(devfreq->dev.parent);
@@ -660,6 +767,7 @@ struct devfreq *devfreq_add_device(struct device *dev,
devfreq->dev.parent = dev;
devfreq->dev.class = devfreq_class;
devfreq->dev.release = devfreq_dev_release;
+ INIT_LIST_HEAD(&devfreq->node);
devfreq->profile = profile;
strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN);
devfreq->previous_freq = profile->initial_freq;
@@ -681,7 +789,6 @@ struct devfreq *devfreq_add_device(struct device *dev,
err = -EINVAL;
goto err_dev;
}
- devfreq->min_freq = devfreq->scaling_min_freq;
devfreq->scaling_max_freq = find_available_max_freq(devfreq);
if (!devfreq->scaling_max_freq) {
@@ -689,7 +796,6 @@ struct devfreq *devfreq_add_device(struct device *dev,
err = -EINVAL;
goto err_dev;
}
- devfreq->max_freq = devfreq->scaling_max_freq;
devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev);
atomic_set(&devfreq->suspend_count, 0);
@@ -703,33 +809,56 @@ struct devfreq *devfreq_add_device(struct device *dev,
goto err_out;
}
- devfreq->trans_table = devm_kzalloc(&devfreq->dev,
+ devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev,
array3_size(sizeof(unsigned int),
devfreq->profile->max_state,
devfreq->profile->max_state),
GFP_KERNEL);
- if (!devfreq->trans_table) {
+ if (!devfreq->stats.trans_table) {
mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_devfreq;
}
- devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
+ devfreq->stats.time_in_state = devm_kcalloc(&devfreq->dev,
devfreq->profile->max_state,
- sizeof(unsigned long),
+ sizeof(*devfreq->stats.time_in_state),
GFP_KERNEL);
- if (!devfreq->time_in_state) {
+ if (!devfreq->stats.time_in_state) {
mutex_unlock(&devfreq->lock);
err = -ENOMEM;
goto err_devfreq;
}
- devfreq->last_stat_updated = jiffies;
+ devfreq->stats.total_trans = 0;
+ devfreq->stats.last_update = get_jiffies_64();
srcu_init_notifier_head(&devfreq->transition_notifier_list);
mutex_unlock(&devfreq->lock);
+ err = dev_pm_qos_add_request(dev, &devfreq->user_min_freq_req,
+ DEV_PM_QOS_MIN_FREQUENCY, 0);
+ if (err < 0)
+ goto err_devfreq;
+ err = dev_pm_qos_add_request(dev, &devfreq->user_max_freq_req,
+ DEV_PM_QOS_MAX_FREQUENCY,
+ PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE);
+ if (err < 0)
+ goto err_devfreq;
+
+ devfreq->nb_min.notifier_call = qos_min_notifier_call;
+ err = dev_pm_qos_add_notifier(devfreq->dev.parent, &devfreq->nb_min,
+ DEV_PM_QOS_MIN_FREQUENCY);
+ if (err)
+ goto err_devfreq;
+
+ devfreq->nb_max.notifier_call = qos_max_notifier_call;
+ err = dev_pm_qos_add_notifier(devfreq->dev.parent, &devfreq->nb_max,
+ DEV_PM_QOS_MAX_FREQUENCY);
+ if (err)
+ goto err_devfreq;
+
mutex_lock(&devfreq_list_lock);
governor = try_then_request_governor(devfreq->governor_name);
@@ -1133,6 +1262,14 @@ err_out:
}
EXPORT_SYMBOL(devfreq_remove_governor);
+static ssize_t name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct devfreq *devfreq = to_devfreq(dev);
+ return sprintf(buf, "%s\n", dev_name(devfreq->dev.parent));
+}
+static DEVICE_ATTR_RO(name);
+
static ssize_t governor_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -1303,42 +1440,39 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr,
unsigned long value;
int ret;
+ /*
+ * Protect against theoretical sysfs writes between
+ * device_add and dev_pm_qos_add_request
+ */
+ if (!dev_pm_qos_request_active(&df->user_min_freq_req))
+ return -EAGAIN;
+
ret = sscanf(buf, "%lu", &value);
if (ret != 1)
return -EINVAL;
- mutex_lock(&df->lock);
-
- if (value) {
- if (value > df->max_freq) {
- ret = -EINVAL;
- goto unlock;
- }
- } else {
- unsigned long *freq_table = df->profile->freq_table;
-
- /* Get minimum frequency according to sorting order */
- if (freq_table[0] < freq_table[df->profile->max_state - 1])
- value = freq_table[0];
- else
- value = freq_table[df->profile->max_state - 1];
- }
+ /* Round down to kHz for PM QoS */
+ ret = dev_pm_qos_update_request(&df->user_min_freq_req,
+ value / HZ_PER_KHZ);
+ if (ret < 0)
+ return ret;
- df->min_freq = value;
- update_devfreq(df);
- ret = count;
-unlock:
- mutex_unlock(&df->lock);
- return ret;
+ return count;
}
static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct devfreq *df = to_devfreq(dev);
+ unsigned long min_freq, max_freq;
+
+ mutex_lock(&df->lock);
+ get_freq_range(df, &min_freq, &max_freq);
+ mutex_unlock(&df->lock);
- return sprintf(buf, "%lu\n", max(df->scaling_min_freq, df->min_freq));
+ return sprintf(buf, "%lu\n", min_freq);
}
+static DEVICE_ATTR_RW(min_freq);
static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
@@ -1347,42 +1481,50 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr,
unsigned long value;
int ret;
+ /*
+ * Protect against theoretical sysfs writes between
+ * device_add and dev_pm_qos_add_request
+ */
+ if (!dev_pm_qos_request_active(&df->user_max_freq_req))
+ return -EINVAL;
+
ret = sscanf(buf, "%lu", &value);
if (ret != 1)
return -EINVAL;
- mutex_lock(&df->lock);
-
- if (value) {
- if (value < df->min_freq) {
- ret = -EINVAL;
- goto unlock;
- }
- } else {
- unsigned long *freq_table = df->profile->freq_table;
+ /*
+ * PM QoS frequencies are in kHz so we need to convert. Convert by
+ * rounding upwards so that the acceptable interval never shrinks.
+ *
+ * For example if the user writes "666666666" to sysfs this value will
+ * be converted to 666667 kHz and back to 666667000 Hz before an OPP
+ * lookup, this ensures that an OPP of 666666666Hz is still accepted.
+ *
+ * A value of zero means "no limit".
+ */
+ if (value)
+ value = DIV_ROUND_UP(value, HZ_PER_KHZ);
+ else
+ value = PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE;
- /* Get maximum frequency according to sorting order */
- if (freq_table[0] < freq_table[df->profile->max_state - 1])
- value = freq_table[df->profile->max_state - 1];
- else
- value = freq_table[0];
- }
+ ret = dev_pm_qos_update_request(&df->user_max_freq_req, value);
+ if (ret < 0)
+ return ret;
- df->max_freq = value;
- update_devfreq(df);
- ret = count;
-unlock:
- mutex_unlock(&df->lock);
- return ret;
+ return count;
}
-static DEVICE_ATTR_RW(min_freq);
static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct devfreq *df = to_devfreq(dev);
+ unsigned long min_freq, max_freq;
+
+ mutex_lock(&df->lock);
+ get_freq_range(df, &min_freq, &max_freq);
+ mutex_unlock(&df->lock);
- return sprintf(buf, "%lu\n", min(df->scaling_max_freq, df->max_freq));
+ return sprintf(buf, "%lu\n", max_freq);
}
static DEVICE_ATTR_RW(max_freq);
@@ -1449,18 +1591,47 @@ static ssize_t trans_stat_show(struct device *dev,
devfreq->profile->freq_table[i]);
for (j = 0; j < max_state; j++)
len += sprintf(buf + len, "%10u",
- devfreq->trans_table[(i * max_state) + j]);
- len += sprintf(buf + len, "%10u\n",
- jiffies_to_msecs(devfreq->time_in_state[i]));
+ devfreq->stats.trans_table[(i * max_state) + j]);
+
+ len += sprintf(buf + len, "%10llu\n", (u64)
+ jiffies64_to_msecs(devfreq->stats.time_in_state[i]));
}
len += sprintf(buf + len, "Total transition : %u\n",
- devfreq->total_trans);
+ devfreq->stats.total_trans);
return len;
}
-static DEVICE_ATTR_RO(trans_stat);
+
+static ssize_t trans_stat_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct devfreq *df = to_devfreq(dev);
+ int err, value;
+
+ if (df->profile->max_state == 0)
+ return count;
+
+ err = kstrtoint(buf, 10, &value);
+ if (err || value != 0)
+ return -EINVAL;
+
+ mutex_lock(&df->lock);
+ memset(df->stats.time_in_state, 0, (df->profile->max_state *
+ sizeof(*df->stats.time_in_state)));
+ memset(df->stats.trans_table, 0, array3_size(sizeof(unsigned int),
+ df->profile->max_state,
+ df->profile->max_state));
+ df->stats.total_trans = 0;
+ df->stats.last_update = get_jiffies_64();
+ mutex_unlock(&df->lock);
+
+ return count;
+}
+static DEVICE_ATTR_RW(trans_stat);
static struct attribute *devfreq_attrs[] = {
+ &dev_attr_name.attr,
&dev_attr_governor.attr,
&dev_attr_available_governors.attr,
&dev_attr_cur_freq.attr,
@@ -1474,6 +1645,81 @@ static struct attribute *devfreq_attrs[] = {
};
ATTRIBUTE_GROUPS(devfreq);
+/**
+ * devfreq_summary_show() - Show the summary of the devfreq devices
+ * @s: seq_file instance to show the summary of devfreq devices
+ * @data: not used
+ *
+ * Show the summary of the devfreq devices via 'devfreq_summary' debugfs file.
+ * It helps that user can know the detailed information of the devfreq devices.
+ *
+ * Return 0 always because it shows the information without any data change.
+ */
+static int devfreq_summary_show(struct seq_file *s, void *data)
+{
+ struct devfreq *devfreq;
+ struct devfreq *p_devfreq = NULL;
+ unsigned long cur_freq, min_freq, max_freq;
+ unsigned int polling_ms;
+
+ seq_printf(s, "%-30s %-10s %-10s %-15s %10s %12s %12s %12s\n",
+ "dev_name",
+ "dev",
+ "parent_dev",
+ "governor",
+ "polling_ms",
+ "cur_freq_Hz",
+ "min_freq_Hz",
+ "max_freq_Hz");
+ seq_printf(s, "%30s %10s %10s %15s %10s %12s %12s %12s\n",
+ "------------------------------",
+ "----------",
+ "----------",
+ "---------------",
+ "----------",
+ "------------",
+ "------------",
+ "------------");
+
+ mutex_lock(&devfreq_list_lock);
+
+ list_for_each_entry_reverse(devfreq, &devfreq_list, node) {
+#if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE)
+ if (!strncmp(devfreq->governor_name, DEVFREQ_GOV_PASSIVE,
+ DEVFREQ_NAME_LEN)) {
+ struct devfreq_passive_data *data = devfreq->data;
+
+ if (data)
+ p_devfreq = data->parent;
+ } else {
+ p_devfreq = NULL;
+ }
+#endif
+
+ mutex_lock(&devfreq->lock);
+ cur_freq = devfreq->previous_freq,
+ get_freq_range(devfreq, &min_freq, &max_freq);
+ polling_ms = devfreq->profile->polling_ms,
+ mutex_unlock(&devfreq->lock);
+
+ seq_printf(s,
+ "%-30s %-10s %-10s %-15s %10d %12ld %12ld %12ld\n",
+ dev_name(devfreq->dev.parent),
+ dev_name(&devfreq->dev),
+ p_devfreq ? dev_name(&p_devfreq->dev) : "null",
+ devfreq->governor_name,
+ polling_ms,
+ cur_freq,
+ min_freq,
+ max_freq);
+ }
+
+ mutex_unlock(&devfreq_list_lock);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(devfreq_summary);
+
static int __init devfreq_init(void)
{
devfreq_class = class_create(THIS_MODULE, "devfreq");
@@ -1490,6 +1736,11 @@ static int __init devfreq_init(void)
}
devfreq_class->dev_groups = devfreq_groups;
+ devfreq_debugfs = debugfs_create_dir("devfreq", NULL);
+ debugfs_create_file("devfreq_summary", 0444,
+ devfreq_debugfs, NULL,
+ &devfreq_summary_fops);
+
return 0;
}
subsys_initcall(devfreq_init);
@@ -1683,7 +1934,7 @@ static void devm_devfreq_notifier_release(struct device *dev, void *res)
/**
* devm_devfreq_register_notifier()
- - Resource-managed devfreq_register_notifier()
+ * - Resource-managed devfreq_register_notifier()
* @dev: The devfreq user device. (parent of devfreq)
* @devfreq: The devfreq object.
* @nb: The notifier block to be unregistered.
@@ -1719,7 +1970,7 @@ EXPORT_SYMBOL(devm_devfreq_register_notifier);
/**
* devm_devfreq_unregister_notifier()
- - Resource-managed devfreq_unregister_notifier()
+ * - Resource-managed devfreq_unregister_notifier()
* @dev: The devfreq user device. (parent of devfreq)
* @devfreq: The devfreq object.
* @nb: The notifier block to be unregistered.