From: Shridhar Rasal <sra...@nvidia.com>
This patch adds support for watermark events. These events inform
the governor that the device load has gone below (low watermark) or
above (high watermark) certain load value.
Signed-off-by: Shridhar Rasal <sra...@nvidia.com>
Signed-off-by: Arto Merilainen <amerilai...@nvidia.com>
---
drivers/devfreq/devfreq.c | 19 +++++++++++++++++++
drivers/devfreq/governor.h | 1 +
include/linux/devfreq.h | 26 ++++++++++++++++++++++++++
3 files changed, 46 insertions(+)
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 30b538d8cc90..8333d024132a 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -1050,6 +1050,25 @@ static struct attribute *devfreq_attrs[] = {
};
ATTRIBUTE_GROUPS(devfreq);
+/**
+ * devfreq_watermark_event() - Handles watermark events
+ * @devfreq: the devfreq instance to be updated
+ * @type: type of watermark event
+ */
+int devfreq_watermark_event(struct devfreq *devfreq, int type)
+{
+ if (!devfreq)
+ return -EINVAL;
+
+ if (!devfreq->governor)
+ return -EINVAL;
+
+ return devfreq->governor->event_handler(devfreq,
+ DEVFREQ_GOV_WMARK, &type);
+}
+EXPORT_SYMBOL(devfreq_watermark_event);
+
+
static int __init devfreq_init(void)
{
devfreq_class = class_create(THIS_MODULE, "devfreq");
diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h
index fad7d6321978..fb9875388f3f 100644
--- a/drivers/devfreq/governor.h
+++ b/drivers/devfreq/governor.h
@@ -24,6 +24,7 @@
#define DEVFREQ_GOV_INTERVAL 0x3
#define DEVFREQ_GOV_SUSPEND 0x4
#define DEVFREQ_GOV_RESUME 0x5
+#define DEVFREQ_GOV_WMARK 0x6
/* Caution: devfreq->lock must be locked before calling update_devfreq */
extern int update_devfreq(struct devfreq *devfreq);
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index f1863dcd83ea..b5bf6c4fe286 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -21,6 +21,12 @@
struct devfreq;
+enum watermark_type {
+ NO_WATERMARK_EVENT = 0,
+ HIGH_WATERMARK_EVENT = 1,
+ LOW_WATERMARK_EVENT = 2
+};
+
/**
* struct devfreq_dev_status - Data given from devfreq user device to
* governors. Represents the performance
@@ -68,6 +74,16 @@ struct devfreq_dev_status {
* status to devfreq, which is used by governors.
* @get_cur_freq: The device should provide the current frequency
* at which it is operating.
+ * @set_high_wmark: This is an optional callback to set high
+ * watermark for watermark event. The value is
+ * be scaled between 0 and 1000 where 1000 equals to
+ * 100% load. Setting this value to 1000 disables
+ * the event
+ * @set_low_wmark: This is an optional callback to set low
+ * watermark for watermark event. The value is
+ * be scaled between 0 and 1000 where 1000 equals to
+ * 100% load. Setting this value to 0 disables the
+ * event.
* @exit: An optional callback that is called when devfreq
* is removing the devfreq object due to error or
* from devfreq_remove_device() call. If the user
@@ -84,6 +100,8 @@ struct devfreq_dev_profile {
int (*get_dev_status)(struct device *dev,
struct devfreq_dev_status *stat);
int (*get_cur_freq)(struct device *dev, unsigned long *freq);
+ int (*set_high_wmark)(struct device *dev, unsigned int val);
+ int (*set_low_wmark)(struct device *dev, unsigned int val);
void (*exit)(struct device *dev);
unsigned int *freq_table;
@@ -191,6 +209,8 @@ extern void devm_devfreq_remove_device(struct device *dev,
/* Supposed to be called by PM_SLEEP/PM_RUNTIME callbacks */
extern int devfreq_suspend_device(struct devfreq *devfreq);
extern int devfreq_resume_device(struct devfreq *devfreq);
+extern int devfreq_watermark_event(struct devfreq *devfreq,
+ int type);
/* Helper functions for devfreq user device driver with OPP. */
extern struct dev_pm_opp *devfreq_recommended_opp(struct device *dev,
@@ -289,6 +309,12 @@ static inline void
devm_devfreq_unregister_opp_notifier(struct device *dev,
struct devfreq *devfreq)
{
}
+
+static inline int devfreq_watermark_event(struct devfreq *devfreq,
+ int type)
+{
+ return 0;
+}
#endif /* CONFIG_PM_DEVFREQ */
#endif /* __LINUX_DEVFREQ_H__ */
--
1.8.1.5
--
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