[RFC PATCHv3 0/7] devfreq: Add devfreq-event class to provide raw data for devfreq device

[RFC PATCHv3 0/7] devfreq: Add devfreq-event class to provide raw data for devfreq device

[Chanwoo Choi]

This patchset add new devfreq_event class to provide raw data to determine
current utilization of device  which is used for devfreq governor.

[Description of devfreq-event class]
This patchset add new devfreq_event class for devfreq_event device which provide
raw data (e.g., memory bus utilization/GPU utilization). This raw data from
devfreq_event data would be used for the governor of devfreq subsystem.
- devfreq_event device : Provide raw data for governor of existing devfreq device
- devfreq device       : Monitor device state and change frequency/voltage of device
                         using the raw data from devfreq_event device

The devfreq subsystem support generic DVFS(Dynamic Voltage/Frequency Scaling)
for Non-CPU Devices. The devfreq device would dertermine current device state
using various governor (e.g., ondemand, performance, powersave). After completed
determination of system state, devfreq device would change the frequency/voltage
of devfreq device according to the result of governor.

But, devfreq governor must need basic data which indicates current device state.
Existing devfreq subsystem only consider devfreq device which check current system
state and determine proper system state using basic data. There is no subsystem
for device providing basic data to devfreq device.

The devfreq subsystem must need devfreq_event device(data-provider device) for
existing devfreq device. So, this patch add new devfreq_event class for
devfreq_event device which read various basic data(e.g, memory bus utilization,
GPU utilization) and provide measured data to existing devfreq device through
standard APIs of devfreq_event class.

The following description explains the feature of two kind of devfreq class:
- devfreq class (existing)
 : devfreq consumer device use raw data from devfreq_event device for
   determining proper current system state and change voltage/frequency
   dynamically using various governors.
- devfreq_event class (new)
 : Provide measured raw data to devfreq device for governor

Also, the devfreq-event device would support various type event as following:
 : DEVFREQ_EVENT_TYPE_RAW_DATA
 : DEVFREQ_EVENT_TYPE_UTILIZATION
 : DEVFREQ_EVENT_TYPE_BANDWIDTH
 : DEVFREQ_EVENT_TYPE_LATENCY

[For example]
If board dts includes PPMU_DMC0/DMC1/LEFTBUS/RIGHTBUS event node,
would show following sysfs entry. Also devfreq driver(e.g., exynos4_bus.c)
can get the instance of devfreq-event device by using provided API and then
get raw data which reflect the current state of device.

-sh-3.2# cd /sys/class/devfreq-event/
-sh-3.2# ls -al
total 0
drwxr-xr-x  2 root root 0 Jan  9 16:47 .
drwxr-xr-x 37 root root 0 Jan  9 16:47 ..
lrwxrwxrwx  1 root root 0 Jan  9 16:47 event.0 -> ../../devices/soc/106a0000.ppmu_dmc0/devfreq-event/event.0
lrwxrwxrwx  1 root root 0 Jan  9 16:47 event.1 -> ../../devices/soc/106b0000.ppmu_dmc1/devfreq-event/event.1
lrwxrwxrwx  1 root root 0 Jan  9 16:47 event.2 -> ../../devices/soc/112a0000.ppmu_rightbus/devfreq-event/event.2
lrwxrwxrwx  1 root root 0 Jan  9 16:47 event.3 -> ../../devices/soc/116a0000.ppmu_leftbus0/devfreq-event/event.3
-sh-3.2# 

Changes from v2:
1. devfreq-event class driver
- Rename all the helper functions of devfreq-event device
- Add devfreq_event_remove_edev() instead of devfreq_put_event_dev()
- Add devfreq_event_release_edev() to initialize it before put device
- Add the detailed description of devfreq-event API
- Add the attributes of devfreq-event class (enable_count)
- Check the overflow about event/total_event data in devfreq_event_get_event()
- Remove the 'exclusive flag' feature
- Set set_event()/get_event() functions as mandary
- Add missing of_node_put() call
- Change variable type of 'get_event()' funciton from 'int' to 'u64'
2. exynos-ppmu driver
- Remove un-used field (struct devfreq)
- Use 'of_get_child_by_name()' instead of 'of_find_node_by_name()'
- Add missing of_node_put() call
- Fix wrong clock control
- Use devfreq_event_remove_edev() instead of devfreq_remove_device()
- Add the documentation for exynos-ppmu driver
- Remove 'enable/disable/is_enabled/reset' function of exynos-ppmu driver
3. exynos3250-rinato.dts
- Add ppmu_{leftbus|rightbus} dt node and remove ppmu_cpu dt node

Changes from v1:
- Code clean
- Add the description of devfreq-event structure
- Add 'is_enabled' function to devfreq_event_ops structure
- Add 'enable_count' field to devfreq_event_dev structure
- Check whether devfreq-event device is enabled or not
  during calling devfreq_event API
- Define the type of devfreq-event device as following
  : DEVFREQ_EVENT_TYPE_RAW_DATA
  : DEVFREQ_EVENT_TYPE_UTILIZATION
  : DEVFREQ_EVENT_TYPE_BANDWIDTH
  : DEVFREQ_EVENT_TYPE_LATENCY
- Add the exclusive feature of devfreq-event device.
  If devfreq-event device is used on only on devfreq driver,
  should used 'devfreq_enable_event_dev_exclusive()' function
- Add new patch6 for test on Exynos3250-based Rinato board

Chanwoo Choi (7):
  devfreq: event: Add new devfreq_event class to provide basic data for devfreq governor
  devfreq: event: Add the list of supported devfreq-event type
  devfreq: event: Add exynos-ppmu devfreq event driver
  devfreq: event: Add documentation for exynos-ppmu devfreq-event driver
  ARM: dts: Add PPMU dt node for Exynos3250
  ARM: dts: Add PPMU dt node for Exynos4 SoC
  ARM: dts: exynos: Add PPMU dt node to Exynos3250-based Rinato board

 .../bindings/devfreq/event/exynos-ppmu.txt         |  56 +++
 arch/arm/boot/dts/exynos3250-rinato.dts            |  40 ++
 arch/arm/boot/dts/exynos3250.dtsi                  |  66 +++
 arch/arm/boot/dts/exynos4.dtsi                     |  96 +++++
 arch/arm/boot/dts/exynos4210.dtsi                  |   8 +
 drivers/devfreq/Kconfig                            |  11 +
 drivers/devfreq/Makefile                           |   5 +-
 drivers/devfreq/devfreq-event.c                    | 476 +++++++++++++++++++++
 drivers/devfreq/event/Makefile                     |   2 +
 drivers/devfreq/event/exynos-ppmu.c                | 404 +++++++++++++++++
 include/linux/devfreq.h                            | 165 +++++++
 11 files changed, 1328 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt
 create mode 100644 drivers/devfreq/devfreq-event.c
 create mode 100644 drivers/devfreq/event/Makefile
 create mode 100644 drivers/devfreq/event/exynos-ppmu.c

-- 
1.8.5.5

[RFC PATCHv3 1/7] devfreq: event: Add new devfreq_event class to provide basic data for devfreq governor

[Chanwoo Choi]

This patch add new devfreq_event class for devfreq_event device which provide
raw data (e.g., memory bus utilization/GPU utilization). This raw data from
devfreq_event data would be used for the governor of devfreq subsystem.
- devfreq_event device : Provide raw data for governor of existing devfreq device
- devfreq device       : Monitor device state and change frequency/voltage of device
                         using the raw data from devfreq_event device

The devfreq subsystem support generic DVFS(Dynamic Voltage/Frequency Scaling)
for Non-CPU Devices. The devfreq device would dertermine current device state
using various governor (e.g., ondemand, performance, powersave). After completed
determination of system state, devfreq device would change the frequency/voltage
of devfreq device according to the result of governor.

But, devfreq governor must need basic data which indicates current device state.
Existing devfreq subsystem only consider devfreq device which check current system
state and determine proper system state using basic data. There is no subsystem
for device providing basic data to devfreq device.

The devfreq subsystem must need devfreq_event device(data-provider device) for
existing devfreq device. So, this patch add new devfreq_event class for
devfreq_event device which read various basic data(e.g, memory bus utilization,
GPU utilization) and provide measured data to existing devfreq device through
standard APIs of devfreq_event class.

The following description explains the feature of two kind of devfreq class:
- devfreq class (existing)
 : devfreq consumer device use raw data from devfreq_event device for
   determining proper current system state and change voltage/frequency
   dynamically using various governors.

- devfreq_event class (new)
 : Provide measured raw data to devfreq device for governor

Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/devfreq/Kconfig         |   2 +
 drivers/devfreq/Makefile        |   5 +-
 drivers/devfreq/devfreq-event.c | 440 ++++++++++++++++++++++++++++++++++++++++
 drivers/devfreq/event/Makefile  |   1 +
 include/linux/devfreq.h         | 146 +++++++++++++
 5 files changed, 593 insertions(+), 1 deletion(-)
 create mode 100644 drivers/devfreq/devfreq-event.c
 create mode 100644 drivers/devfreq/event/Makefile

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index faf4e70..4d15b62 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -87,4 +87,6 @@ config ARM_EXYNOS5_BUS_DEVFREQ
 	  It reads PPMU counters of memory controllers and adjusts the
 	  operating frequencies and voltages with OPP support.
 
+comment "DEVFREQ Event Drivers"
+
 endif # PM_DEVFREQ
diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile
index 16138c9..a1ffabe 100644
--- a/drivers/devfreq/Makefile
+++ b/drivers/devfreq/Makefile
@@ -1,4 +1,4 @@
-obj-$(CONFIG_PM_DEVFREQ)	+= devfreq.o
+obj-$(CONFIG_PM_DEVFREQ)		+= devfreq.o devfreq-event.o
 obj-$(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)	+= governor_simpleondemand.o
 obj-$(CONFIG_DEVFREQ_GOV_PERFORMANCE)	+= governor_performance.o
 obj-$(CONFIG_DEVFREQ_GOV_POWERSAVE)	+= governor_powersave.o
@@ -7,3 +7,6 @@ obj-$(CONFIG_DEVFREQ_GOV_USERSPACE)	+= governor_userspace.o
 # DEVFREQ Drivers
 obj-$(CONFIG_ARM_EXYNOS4_BUS_DEVFREQ)	+= exynos/
 obj-$(CONFIG_ARM_EXYNOS5_BUS_DEVFREQ)	+= exynos/
+
+# DEVFREQ Event Drivers
+obj-$(CONFIG_PM_DEVFREQ)		+= event/
diff --git a/drivers/devfreq/devfreq-event.c b/drivers/devfreq/devfreq-event.c
new file mode 100644
index 0000000..eaf59c1
--- /dev/null
+++ b/drivers/devfreq/devfreq-event.c
@@ -0,0 +1,440 @@
+/*
+ * devfreq-event: Generic DEVFREQ Event class driver
+ *
+ * Copyright (C) 2014 Samsung Electronics
+ * Chanwoo Choi <cw00.choi@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This driver is based on drivers/devfreq/devfreq.c.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/pm_opp.h>
+#include <linux/devfreq.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+#include <linux/list.h>
+#include <linux/printk.h>
+#include <linux/hrtimer.h>
+#include <linux/of.h>
+#include "governor.h"
+
+static struct class *devfreq_event_class;
+
+/* The list of all devfreq event list */
+static LIST_HEAD(devfreq_event_list);
+static DEFINE_MUTEX(devfreq_event_list_lock);
+
+#define to_devfreq_event(DEV) container_of(DEV, struct devfreq_event_dev, dev)
+
+/**
+ * devfreq_event_enable_edev() - Enable the devfreq-event dev and increase
+ *				 the enable_count of devfreq-event dev.
+ * @edev	: the devfreq-event device
+ *
+ * Note that this function increase the enable_count and enable the
+ * devfreq-event device. The devfreq-event device should be enabled before
+ * using it by devfreq device.
+ */
+int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
+{
+	int ret = 0;
+
+	if (!edev || !edev->desc)
+		return -EINVAL;
+
+	mutex_lock(&edev->lock);
+	if (edev->desc->ops && edev->desc->ops->enable) {
+		ret = edev->desc->ops->enable(edev);
+		if (ret < 0)
+			goto err;
+	}
+	edev->enable_count++;
+err:
+	mutex_unlock(&edev->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_enable_edev);
+
+/**
+ * devfreq_event_disable_edev() - Disable the devfreq-event dev and decrease
+ *				  the enable_count of the devfreq-event dev.
+ * @edev	: the devfreq-event device
+ *
+ * Note that this function decrease the enable_count and disable the
+ * devfreq-event device. After the devfreq-event device is disabled,
+ * devfreq device can't use the devfreq-event device for get/set/reset
+ * operations.
+ */
+int devfreq_event_disable_edev(struct devfreq_event_dev *edev)
+{
+	int ret = 0;
+
+	if (!edev || !edev->desc)
+		return -EINVAL;
+
+	mutex_lock(&edev->lock);
+	if (edev->enable_count > 0) {
+		edev->enable_count--;
+	} else {
+		dev_warn(&edev->dev, "unbalanced enable_count\n");
+		ret = -EINVAL;
+		goto err;
+	}
+
+	if (edev->desc->ops && edev->desc->ops->disable) {
+		ret = edev->desc->ops->disable(edev);
+		if (ret < 0) {
+			edev->enable_count++;
+			goto err;
+		}
+	}
+err:
+	mutex_unlock(&edev->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_disable_edev);
+
+/**
+ * devfreq_event_is_enabled() - Check whether devfreq-event dev is enabled or
+ *				not.
+ * @edev	: the devfreq-event device
+ *
+ * Note that this function check whether devfreq-event dev is enabled or not.
+ * If return true, the devfreq-event dev is enabeld. If return false, the
+ * devfreq-event dev is disabled.
+ */
+bool devfreq_event_is_enabled(struct devfreq_event_dev *edev)
+{
+	bool enabled = false;
+
+	if (!edev || !edev->desc)
+		return enabled;
+
+	mutex_lock(&edev->lock);
+
+	if (edev->enable_count > 0)
+		enabled = true;
+
+	if (edev->desc->ops && edev->desc->ops->is_enabled)
+		enabled |= edev->desc->ops->is_enabled(edev);
+
+	mutex_unlock(&edev->lock);
+
+	return enabled;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_is_enabled);
+
+/**
+ * devfreq_event_set_event() - Set event to devfreq-event dev to start.
+ * @edev	: the devfreq-event device
+ *
+ * Note that this function set the event to the devfreq-event device to start
+ * for getting the event data which could be various event type.
+ */
+int devfreq_event_set_event(struct devfreq_event_dev *edev)
+{
+	int ret;
+
+	if (!edev || !edev->desc)
+		return -EINVAL;
+
+	if (!edev->desc->ops || !edev->desc->ops->set_event)
+		return -EINVAL;
+
+	if (!devfreq_event_is_enabled(edev))
+		return -EPERM;
+
+	mutex_lock(&edev->lock);
+	ret = edev->desc->ops->set_event(edev);
+	mutex_unlock(&edev->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_set_event);
+
+/**
+ * devfreq_event_get_event() - Get event and total_event from devfreq-event dev.
+ * @edev	: the devfreq-event device
+ *
+ * Note that this function get the calculated event data from devfreq-event dev
+ * after stoping the progress of whole sequence of devfreq-event dev. Return
+ * current event data and total_event should be stored in second parameter
+ * (total_event).
+ */
+u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
+{
+	u64 event;
+
+	*total_event = 0;
+
+	if (!edev || !edev->desc)
+		return 0;
+
+	if (!edev->desc->ops || !edev->desc->ops->get_event)
+		return 0;
+
+	if (!devfreq_event_is_enabled(edev))
+		return 0;
+
+	mutex_lock(&edev->lock);
+	event = edev->desc->ops->get_event(edev, total_event);
+	mutex_unlock(&edev->lock);
+
+	return event;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_get_event);
+
+/**
+ * devfreq_event_reset_event() - Reset all opeations of devfreq-event dev.
+ * @edev	: the devfreq-event device
+ *
+ * Note that this function stop all operations of devfreq-event dev and reset
+ * the current event data to make the devfreq-event device into initial state.
+ */
+int devfreq_event_reset_event(struct devfreq_event_dev *edev)
+{
+	int ret = 0;
+
+	if (!edev || !edev->desc)
+		return -EINVAL;
+
+	if (!devfreq_event_is_enabled(edev))
+		return -EPERM;
+
+	mutex_lock(&edev->lock);
+	if (edev->desc->ops && edev->desc->ops->reset)
+		ret = edev->desc->ops->reset(edev);
+	mutex_unlock(&edev->lock);
+
+	if (ret < 0)
+		return -EINVAL;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_reset_event);
+
+/**
+ * devfreq_event_get_drvdata() - Return driver-data of devfreq-event dev.
+ * @edev	: the devfreq-event device
+ *
+ * Note that this function return the driver-data of devfreq-event device.
+ */
+void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
+{
+	return edev->desc->driver_data;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_get_drvdata);
+
+/**
+ * devfreq_event_get_edev_by_phandle() - Get the devfreq-event dev from
+ *					 devicetree.
+ * @dev		: the pointer to the given device
+ * @index	: the index into list of devfreq-event device
+ *
+ * Note that this function return the pointer of devfreq-event device.
+ */
+struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(struct device *dev,
+						      int index)
+{
+	struct device_node *node;
+	struct devfreq_event_dev *edev;
+
+	if (!dev->of_node) {
+		dev_err(dev, "device does not have a device node entry\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	node = of_parse_phandle(dev->of_node, "devfreq-events", index);
+	if (!node) {
+		dev_err(dev, "failed to get phandle in %s node\n",
+			dev->of_node->full_name);
+		return ERR_PTR(-ENODEV);
+	}
+
+	mutex_lock(&devfreq_event_list_lock);
+	list_for_each_entry(edev, &devfreq_event_list, node) {
+		if (!strcmp(edev->desc->name, node->name))
+			goto out;
+	}
+	edev = NULL;
+out:
+	mutex_unlock(&devfreq_event_list_lock);
+
+	if (!edev) {
+		dev_err(dev, "unable to get devfreq-event device : %s\n",
+			node->name);
+		return ERR_PTR(-ENODEV);
+	}
+
+	return edev;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_get_edev_by_phandle);
+
+static void devfreq_event_release_edev(struct device *dev)
+{
+	struct devfreq_event_dev *edev = to_devfreq_event(dev);
+	int ret;
+
+	if (!edev) {
+		dev_warn(dev, "failed to release devfreq-event dev\n");
+		return;
+	}
+
+	if (devfreq_event_is_enabled(edev)) {
+		/* Reset the devfreq-event device */
+		ret = devfreq_event_reset_event(edev);
+		if (ret < 0)
+			dev_warn(dev, "failed to reset devfreq-event dev\n");
+
+		/* Disable the devfreq-event device */
+		ret = devfreq_event_disable_edev(edev);
+		if (ret < 0)
+			dev_warn(dev, "failed to disable devfreq-event dev\n");
+	}
+
+	mutex_lock(&devfreq_event_list_lock);
+	list_del(&edev->node);
+	mutex_unlock(&devfreq_event_list_lock);
+}
+
+/**
+ * devfreq_event_add_edev() - Add new devfreq-event device.
+ * @dev		: the device owning the devfreq-event device being created
+ * @desc	: the devfreq-event device's decriptor which include essential
+ *		  data for devfreq-event device.
+ *
+ * Note that this function add new devfreq-event device to devfreq-event class
+ * list and register the device of the devfreq-event device.
+ */
+struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
+						struct devfreq_event_desc *desc)
+{
+	struct devfreq_event_dev *edev;
+	static atomic_t event_no = ATOMIC_INIT(0);
+	int ret;
+
+	if (!dev || !desc)
+		return ERR_PTR(-EINVAL);
+
+	if (!desc->name || !desc->ops)
+		return ERR_PTR(-EINVAL);
+
+	if (!desc->ops->set_event || !desc->ops->get_event)
+		return ERR_PTR(-EINVAL);
+
+	edev = devm_kzalloc(dev, sizeof(*edev), GFP_KERNEL);
+	if (!edev)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_lock(&devfreq_event_list_lock);
+	mutex_init(&edev->lock);
+	edev->desc = desc;
+	edev->dev.parent = dev;
+	edev->dev.class = devfreq_event_class;
+	edev->dev.release = devfreq_event_release_edev;
+
+	dev_set_name(&edev->dev, "event.%d", atomic_inc_return(&event_no) - 1);
+	ret = device_register(&edev->dev);
+	if (ret < 0) {
+		put_device(&edev->dev);
+		mutex_unlock(&devfreq_event_list_lock);
+		return ERR_PTR(ret);
+	}
+	dev_set_drvdata(&edev->dev, edev);
+
+	INIT_LIST_HEAD(&edev->node);
+	list_add(&edev->node, &devfreq_event_list);
+	mutex_unlock(&devfreq_event_list_lock);
+
+	return edev;
+}
+EXPORT_SYMBOL(devfreq_event_add_edev);
+
+/**
+ * devfreq_event_remove_edev() - Remove the devfreq-event device registered.
+ * @dev		: the devfreq-event device
+ *
+ * Note that this function remove the registered devfreq-event device.
+ */
+int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
+{
+	if (!edev)
+		return -EINVAL;
+
+	device_unregister(&edev->dev);
+	put_device(&edev->dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devfreq_event_remove_edev);
+
+/*
+ * Device attributes for devfreq-event class.
+ */
+static ssize_t name_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct devfreq_event_dev *edev = to_devfreq_event(dev);
+
+	if (!edev || !edev->desc)
+		return -EINVAL;
+
+	return sprintf(buf, "%s\n", edev->desc->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t enable_count_show(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct devfreq_event_dev *edev = to_devfreq_event(dev);
+
+	if (!edev || !edev->desc)
+		return -EINVAL;
+
+	return sprintf(buf, "%d\n", edev->enable_count);
+}
+static DEVICE_ATTR_RO(enable_count);
+
+static struct attribute *devfreq_event_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_enable_count.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(devfreq_event);
+
+static int __init devfreq_event_init(void)
+{
+	devfreq_event_class = class_create(THIS_MODULE, "devfreq-event");
+	if (IS_ERR(devfreq_event_class)) {
+		pr_err("%s: couldn't create class\n", __FILE__);
+		return PTR_ERR(devfreq_event_class);
+	}
+
+	devfreq_event_class->dev_groups = devfreq_event_groups;
+
+	return 0;
+}
+subsys_initcall(devfreq_event_init);
+
+static void __exit devfreq_event_exit(void)
+{
+	class_destroy(devfreq_event_class);
+}
+module_exit(devfreq_event_exit);
+
+MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
+MODULE_DESCRIPTION("DEVFREQ-Event class support");
+MODULE_LICENSE("GPL");
diff --git a/drivers/devfreq/event/Makefile b/drivers/devfreq/event/Makefile
new file mode 100644
index 0000000..dc56005
--- /dev/null
+++ b/drivers/devfreq/event/Makefile
@@ -0,0 +1 @@
+# Exynos DEVFREQ Event Drivers
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index f1863dc..a8d2277 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -175,6 +175,71 @@ struct devfreq {
 	unsigned long last_stat_updated;
 };
 
+/**
+ * struct devfreq_event_dev - the devfreq-event device
+ *
+ * @node	: Contain the devfreq-event device that have been registered.
+ * @dev		: the device registered by devfreq-event class. dev.parent is
+ *		  the device using devfreq-event.
+ * @lock	: a mutex to protect accessing devfreq-event.
+ * @enable_count: the number of enable function have been called.
+ * @desc	: the description for devfreq-event device.
+ *
+ * This structure contains devfreq-event device information.
+ */
+struct devfreq_event_dev {
+	struct list_head node;
+
+	struct device dev;
+	struct mutex lock;
+	u32 enable_count;
+
+	const struct devfreq_event_desc *desc;
+};
+
+/**
+ * struct devfreq_event_ops - the operations of devfreq-event device
+ *
+ * @enable	: Enable the devfreq-event device.
+ * @disable	: Disable the devfreq-event device.
+ * @is_enabled	: Return true if the devfreq-event is enabled, false if not.
+ * @reset	: Reset all setting of the devfreq-event device.
+ * @set_event	: Set the specific event type for the devfreq-event device.
+ * @get_event	: Get the result of the devfreq-event devie with specific
+ *		  event type.
+ *
+ * This structure contains devfreq-event device operations which can be
+ * implemented by devfreq-event device drivers.
+ */
+struct devfreq_event_ops {
+	/* Optional functions */
+	int (*enable)(struct devfreq_event_dev *event_dev);
+	int (*disable)(struct devfreq_event_dev *event_dev);
+	bool (*is_enabled)(struct devfreq_event_dev *event_dev);
+	int (*reset)(struct devfreq_event_dev *event_dev);
+
+	/* Mandatory functions */
+	int (*set_event)(struct devfreq_event_dev *event_dev);
+	u64 (*get_event)(struct devfreq_event_dev *event_dev, u64 *total_event);
+};
+
+/**
+ * struct devfreq_event_desc - the descriptor of devfreq-event device
+ *
+ * @name	: the name of devfreq-event device.
+ * @driver_data	: the private data for devfreq-event driver.
+ * @ops		: the operation to control devfreq-event device.
+ *
+ * Each devfreq-event device is described with a this structure.
+ * This structure contains the various data for devfreq-event device.
+ */
+struct devfreq_event_desc {
+	const char *name;
+	void *driver_data;
+
+	struct devfreq_event_ops *ops;
+};
+
 #if defined(CONFIG_PM_DEVFREQ)
 extern struct devfreq *devfreq_add_device(struct device *dev,
 				  struct devfreq_dev_profile *profile,
@@ -204,6 +269,21 @@ extern int devm_devfreq_register_opp_notifier(struct device *dev,
 extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
 						struct devfreq *devfreq);
 
+/* Functions for devfreq event device */
+extern int devfreq_event_enable_edev(struct devfreq_event_dev *edev);
+extern int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
+extern bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
+extern int devfreq_event_set_event(struct devfreq_event_dev *edev);
+extern u64 devfreq_event_get_event(struct devfreq_event_dev *edev,
+				u64 *total_event);
+extern int devfreq_event_reset_event(struct devfreq_event_dev *edev);
+extern void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev);
+extern struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
+				struct device *dev, int index);
+extern struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
+				struct devfreq_event_desc *desc);
+extern int devfreq_event_remove_edev(struct devfreq_event_dev *edev);
+
 #if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
 /**
  * struct devfreq_simple_ondemand_data - void *data fed to struct devfreq
@@ -233,6 +313,13 @@ static inline struct devfreq *devfreq_add_device(struct device *dev,
 	return ERR_PTR(-ENOSYS);
 }
 
+static inline struct devfreq_event_dev *devfreq_add_event_device(
+					struct device *dev,
+					struct devfreq_event_desc *desc);
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline int devfreq_remove_device(struct devfreq *devfreq)
 {
 	return 0;
@@ -289,6 +376,65 @@ static inline void devm_devfreq_unregister_opp_notifier(struct device *dev,
 							struct devfreq *devfreq)
 {
 }
+
+static inline void *event_dev_get_drvdata(struct devfreq_event_dev *event_dev)
+{
+	return ERR_PTR(-EINVAL);
+}
+
+static inline int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
+{
+	return -EINVAL;
+}
+
+static inline int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
+{
+	return -EINVAL;
+}
+
+static inline bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
+{
+	return false;
+}
+
+static inline int devfreq_event_set_event(struct devfreq_event_dev *edev);
+{
+	return -EINVAL;
+}
+
+static inline u64 devfreq_event_get_event(struct devfreq_event_dev *edev
+					u64 *total_event);
+{
+	return 0;
+}
+
+static inline int devfreq_event_reset_event(struct devfreq_event_dev *edev);
+{
+	return -EINVAL;
+}
+
+static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev);
+{
+	return ERR_PTR(-EINVAL);
+}
+
+static inline struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
+					struct device *dev, int index);
+{
+	return ERR_PTR(-EINVAL);
+}
+
+static inline struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
+					struct devfreq_event_desc *desc);
+{
+	return ERR_PTR(-EINVAL);
+}
+
+static inline int devfreq_event_remove_edev(struct devfreq_event_dev *edev);
+{
+	return -EINVAL;
+}
+
 #endif /* CONFIG_PM_DEVFREQ */
 
 #endif /* __LINUX_DEVFREQ_H__ */
-- 
1.8.5.5

[RFC PATCHv3 2/7] devfreq: event: Add the list of supported devfreq-event type

[Chanwoo Choi]

This patch adds the list of supported devfreq-event type as following.
Each devfreq-event device driver would support the various devfreq-event type
for devfreq governor at the same time.
- DEVFREQ_EVENT_TYPE_RAW_DATA
- DEVFREQ_EVENT_TYPE_UTILIZATION
- DEVFREQ_EVENT_TYPE_BANDWIDTH
- DEVFREQ_EVENT_TYPE_LATENCY

Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/devfreq/devfreq-event.c | 44 +++++++++++++++++++++++++++++++++++++----
 include/linux/devfreq.h         | 29 ++++++++++++++++++++++-----
 2 files changed, 64 insertions(+), 9 deletions(-)

diff --git a/drivers/devfreq/devfreq-event.c b/drivers/devfreq/devfreq-event.c
index eaf59c1..9444f93 100644
--- a/drivers/devfreq/devfreq-event.c
+++ b/drivers/devfreq/devfreq-event.c
@@ -29,6 +29,9 @@
 #include <linux/of.h>
 #include "governor.h"
 
+#define EVENT_TYPE_RAW_DATA_MAX		U64_MAX
+#define EVENT_TYPE_UTILIZATION_MAX	100
+
 static struct class *devfreq_event_class;
 
 /* The list of all devfreq event list */
@@ -144,7 +147,8 @@ EXPORT_SYMBOL_GPL(devfreq_event_is_enabled);
  * Note that this function set the event to the devfreq-event device to start
  * for getting the event data which could be various event type.
  */
-int devfreq_event_set_event(struct devfreq_event_dev *edev)
+int devfreq_event_set_event(struct devfreq_event_dev *edev,
+				enum devfreq_event_type type)
 {
 	int ret;
 
@@ -158,7 +162,15 @@ int devfreq_event_set_event(struct devfreq_event_dev *edev)
 		return -EPERM;
 
 	mutex_lock(&edev->lock);
-	ret = edev->desc->ops->set_event(edev);
+
+	if ((edev->desc->type & type) == 0) {
+		dev_err(&edev->dev, "unsupported of devfreq-event type\n");
+		mutex_unlock(&edev->lock);
+		return -EINVAL;
+	}
+
+	ret = edev->desc->ops->set_event(edev, type);
+
 	mutex_unlock(&edev->lock);
 
 	return ret;
@@ -174,7 +186,9 @@ EXPORT_SYMBOL_GPL(devfreq_event_set_event);
  * current event data and total_event should be stored in second parameter
  * (total_event).
  */
-u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
+u64 devfreq_event_get_event(struct devfreq_event_dev *edev,
+				enum devfreq_event_type type,
+				u64 *total_event)
 {
 	u64 event;
 
@@ -190,7 +204,27 @@ u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
 		return 0;
 
 	mutex_lock(&edev->lock);
-	event = edev->desc->ops->get_event(edev, total_event);
+
+	if ((edev->desc->type & type) == 0) {
+		dev_err(&edev->dev, "unsupported of devfreq-event type\n");
+		return -EINVAL;
+	}
+
+	event = edev->desc->ops->get_event(edev, type, total_event);
+
+	switch (type) {
+	case DEVFREQ_EVENT_TYPE_RAW_DATA:
+	case DEVFREQ_EVENT_TYPE_BANDWIDTH:
+	case DEVFREQ_EVENT_TYPE_LATENCY:
+		if ((event > *total_event)
+			|| ((event > EVENT_TYPE_RAW_DATA_MAX) ||
+				*total_event > EVENT_TYPE_RAW_DATA_MAX))
+			event = 0;
+	case DEVFREQ_EVENT_TYPE_UTILIZATION:
+		if (event > EVENT_TYPE_UTILIZATION_MAX)
+			event = 0;
+	}
+
 	mutex_unlock(&edev->lock);
 
 	return event;
@@ -215,8 +249,10 @@ int devfreq_event_reset_event(struct devfreq_event_dev *edev)
 		return -EPERM;
 
 	mutex_lock(&edev->lock);
+
 	if (edev->desc->ops && edev->desc->ops->reset)
 		ret = edev->desc->ops->reset(edev);
+
 	mutex_unlock(&edev->lock);
 
 	if (ret < 0)
diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
index a8d2277..82da235 100644
--- a/include/linux/devfreq.h
+++ b/include/linux/devfreq.h
@@ -197,6 +197,14 @@ struct devfreq_event_dev {
 	const struct devfreq_event_desc *desc;
 };
 
+/* The supported type by devfreq-event device */
+enum devfreq_event_type {
+	DEVFREQ_EVENT_TYPE_RAW_DATA	= BIT(0),
+	DEVFREQ_EVENT_TYPE_UTILIZATION	= BIT(1),
+	DEVFREQ_EVENT_TYPE_BANDWIDTH	= BIT(2),
+	DEVFREQ_EVENT_TYPE_LATENCY	= BIT(3),
+};
+
 /**
  * struct devfreq_event_ops - the operations of devfreq-event device
  *
@@ -219,8 +227,10 @@ struct devfreq_event_ops {
 	int (*reset)(struct devfreq_event_dev *event_dev);
 
 	/* Mandatory functions */
-	int (*set_event)(struct devfreq_event_dev *event_dev);
-	u64 (*get_event)(struct devfreq_event_dev *event_dev, u64 *total_event);
+	int (*set_event)(struct devfreq_event_dev *event_dev,
+			enum devfreq_event_type type);
+	u64 (*get_event)(struct devfreq_event_dev *event_dev,
+			enum devfreq_event_type type, u64 *total_event);
 };
 
 /**
@@ -228,6 +238,10 @@ struct devfreq_event_ops {
  *
  * @name	: the name of devfreq-event device.
  * @driver_data	: the private data for devfreq-event driver.
+ * @event_type	: the supported devfreq-event type among as following
+ *		  - DEVFREQ_EVENT_TYPE_UTILIZATION
+ *		  - DEVFREQ_EVENT_TYPE_BANDWIDTH
+ *		  - DEVFREQ_EVENT_TYPE_LATENCY
  * @ops		: the operation to control devfreq-event device.
  *
  * Each devfreq-event device is described with a this structure.
@@ -236,6 +250,7 @@ struct devfreq_event_ops {
 struct devfreq_event_desc {
 	const char *name;
 	void *driver_data;
+	enum devfreq_event_type type;
 
 	struct devfreq_event_ops *ops;
 };
@@ -273,8 +288,10 @@ extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
 extern int devfreq_event_enable_edev(struct devfreq_event_dev *edev);
 extern int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
 extern bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
-extern int devfreq_event_set_event(struct devfreq_event_dev *edev);
+extern int devfreq_event_set_event(struct devfreq_event_dev *edev,
+				enum devfreq_event_type type);
 extern u64 devfreq_event_get_event(struct devfreq_event_dev *edev,
+				enum devfreq_event_type type,
 				u64 *total_event);
 extern int devfreq_event_reset_event(struct devfreq_event_dev *edev);
 extern void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev);
@@ -397,13 +414,15 @@ static inline bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
 	return false;
 }
 
-static inline int devfreq_event_set_event(struct devfreq_event_dev *edev);
+static inline int devfreq_event_set_event(struct devfreq_event_dev *edev,
+					enum devfreq_event_type type)
 {
 	return -EINVAL;
 }
 
 static inline u64 devfreq_event_get_event(struct devfreq_event_dev *edev
-					u64 *total_event);
+					enum devfreq_event_type type,
+					u64 *total_event)
 {
 	return 0;
 }
-- 
1.8.5.5

[RFC PATCHv3 3/7] devfreq: event: Add exynos-ppmu devfreq event driver

[Chanwoo Choi]

This patch adds exynos-ppmu devfreq-event driver to get performance data
of each IP for Samsung Exynos SoC. These event from Exynos PPMU provide
useful information about the behavior of the SoC that you can use when
analyzing system performance, and made visible and can be counted using
logic in each IP.

This patch is based on existing drivers/devfreq/exynos/exynos-ppmu.c

Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 drivers/devfreq/Kconfig             |   9 +
 drivers/devfreq/event/Makefile      |   1 +
 drivers/devfreq/event/exynos-ppmu.c | 404 ++++++++++++++++++++++++++++++++++++
 3 files changed, 414 insertions(+)
 create mode 100644 drivers/devfreq/event/exynos-ppmu.c

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
index 4d15b62..d4559f7 100644
--- a/drivers/devfreq/Kconfig
+++ b/drivers/devfreq/Kconfig
@@ -89,4 +89,13 @@ config ARM_EXYNOS5_BUS_DEVFREQ
 
 comment "DEVFREQ Event Drivers"
 
+config DEVFREQ_EVENT_EXYNOS_PPMU
+	bool "EXYNOS PPMU (Performance Profiling Monitoring Unit) DEVFREQ event Driver"
+	depends on ARCH_EXYNOS
+	select PM_OPP
+	help
+	 This add the DEVFREQ event driver for Exynos SoC. It provides PPMU
+	 (Performance Profiling Monitoring Unit) counters to estimate the
+	 utilization of each module.
+
 endif # PM_DEVFREQ
diff --git a/drivers/devfreq/event/Makefile b/drivers/devfreq/event/Makefile
index dc56005..be146ea 100644
--- a/drivers/devfreq/event/Makefile
+++ b/drivers/devfreq/event/Makefile
@@ -1 +1,2 @@
 # Exynos DEVFREQ Event Drivers
+obj-$(CONFIG_DEVFREQ_EVENT_EXYNOS_PPMU) += exynos-ppmu.o
diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
new file mode 100644
index 0000000..bf93431
--- /dev/null
+++ b/drivers/devfreq/event/exynos-ppmu.c
@@ -0,0 +1,404 @@
+/*
+ * exynos_ppmu.c - EXYNOS PPMU (Performance Profiling Monitoring Units) support
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd.
+ * Author : Chanwoo Choi <cw00.choi@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This driver is based on drivers/devfreq/exynos/exynos_ppmu.c
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/suspend.h>
+#include <linux/devfreq.h>
+
+#define PPMU_ENABLE             BIT(0)
+#define PPMU_DISABLE            0x0
+#define PPMU_CYCLE_RESET        BIT(1)
+#define PPMU_COUNTER_RESET      BIT(2)
+
+#define PPMU_ENABLE_COUNT0      BIT(0)
+#define PPMU_ENABLE_COUNT1      BIT(1)
+#define PPMU_ENABLE_COUNT2      BIT(2)
+#define PPMU_ENABLE_COUNT3      BIT(3)
+#define PPMU_ENABLE_CYCLE       BIT(31)
+
+#define PPMU_CNTENS		0x10
+#define PPMU_FLAG		0x50
+#define PPMU_CCNT_OVERFLOW	BIT(31)
+#define PPMU_CCNT		0x100
+
+#define PPMU_PMCNT0		0x110
+#define PPMU_PMCNT_OFFSET	0x10
+#define PMCNT_OFFSET(x)		(PPMU_PMCNT0 + (PPMU_PMCNT_OFFSET * x))
+
+#define PPMU_BEVT0SEL		0x1000
+#define PPMU_BEVTSEL_OFFSET	0x100
+#define PPMU_BEVTSEL(x)		(PPMU_BEVT0SEL + (x * PPMU_BEVTSEL_OFFSET))
+
+#define RD_DATA_COUNT		0x5
+#define WR_DATA_COUNT		0x6
+#define RDWR_DATA_COUNT		0x7
+
+enum ppmu_counter {
+	PPMU_PMNCNT0 = 0,
+	PPMU_PMNCNT1,
+	PPMU_PMNCNT2,
+	PPMU_PMNCNT3,
+
+	PPMU_PMNCNT_MAX,
+};
+
+struct exynos_ppmu_data {
+	struct devfreq_event_dev **edev;
+	struct devfreq_event_desc *desc;
+	unsigned int num_events;
+
+	struct device *dev;
+	struct clk *clk_ppmu;
+	struct mutex lock;
+
+	struct __exynos_ppmu {
+		void __iomem *base;
+		unsigned int event[PPMU_PMNCNT_MAX];
+		unsigned int count[PPMU_PMNCNT_MAX];
+		bool ccnt_overflow;
+		bool count_overflow[PPMU_PMNCNT_MAX];
+	} ppmu;
+};
+
+struct __exynos_ppmu_events {
+	char *name;
+	int id;
+} ppmu_events[] = {
+	{ "ppmu-dmc0-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-dmc0-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-dmc0-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-dmc0-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-dmc1-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-dmc1-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-dmc1-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-dmc1-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-cpu-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-cpu-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-cpu-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-cpu-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-rightbus-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-rightbus-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-rightbus-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-rightbus-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-leftbus-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-leftbus-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-leftbus-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-leftbus-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-camif-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-camif-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-camif-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-camif-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-lcd0-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-lcd0-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-lcd0-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-lcd0-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-g3d-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-g3d-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-g3d-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-g3d-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-mfc-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-mfc-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-mfc-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-mfc-pmcnt3", PPMU_PMNCNT3 },
+
+	{ "ppmu-fsys-pmcnt0", PPMU_PMNCNT0 },
+	{ "ppmu-fsys-pmcnt1", PPMU_PMNCNT1 },
+	{ "ppmu-fsys-pmcnt2", PPMU_PMNCNT2 },
+	{ "ppmu-fsys-pmcnt3", PPMU_PMNCNT3 },
+	{ /* sentinel */ },
+};
+
+static int exynos_ppmu_find_ppmu_id(struct devfreq_event_dev *edev)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(ppmu_events); i++)
+		if (!strcmp(edev->desc->name, ppmu_events[i].name))
+			return ppmu_events[i].id;
+
+	return -EINVAL;
+}
+
+static int exynos_ppmu_reset(struct devfreq_event_dev *edev)
+{
+	struct exynos_ppmu_data *data = devfreq_event_get_drvdata(edev);
+
+	__raw_writel(PPMU_CYCLE_RESET | PPMU_COUNTER_RESET, data->ppmu.base);
+	__raw_writel(PPMU_ENABLE_CYCLE  |
+		     PPMU_ENABLE_COUNT0 |
+		     PPMU_ENABLE_COUNT1 |
+		     PPMU_ENABLE_COUNT2 |
+		     PPMU_ENABLE_COUNT3,
+		     data->ppmu.base + PPMU_CNTENS);
+
+	return 0;
+}
+
+static int exynos_ppmu_set_event(struct devfreq_event_dev *edev,
+				enum devfreq_event_type type)
+{
+	struct exynos_ppmu_data *data = devfreq_event_get_drvdata(edev);
+	int id = exynos_ppmu_find_ppmu_id(edev);
+
+	if (id < 0)
+		return id;
+
+	if (type != edev->desc->type)
+		return -EINVAL;
+
+	/* Reset the performance and cycle counters */
+	exynos_ppmu_reset(edev);
+
+	/* Setup count registers to monitor read/write transactions */
+	__raw_writel(RDWR_DATA_COUNT, data->ppmu.base + PPMU_BEVTSEL(id));
+
+	/* Start monitoring of PPMU IP */
+	__raw_writel(PPMU_ENABLE, data->ppmu.base);
+
+	return 0;
+}
+
+static u64 exynos_ppmu_get_event(struct devfreq_event_dev *edev,
+				enum devfreq_event_type type,
+				u64 *total_event)
+{
+	struct exynos_ppmu_data *data = devfreq_event_get_drvdata(edev);
+	int id = exynos_ppmu_find_ppmu_id(edev);
+	u64 event;
+
+	if (id < 0)
+		return id;
+
+	if (type != edev->desc->type)
+		return -EINVAL;
+
+	/* Stop monitoring of PPMU IP */
+	__raw_writel(PPMU_DISABLE, data->ppmu.base);
+
+	/* Read total count cycle from of PPMU IP */
+	*total_event = __raw_readl(data->ppmu.base + PPMU_CCNT);
+
+	if (id == PPMU_PMNCNT3)
+		event = ((__raw_readl(data->ppmu.base + PMCNT_OFFSET(id)) << 8)
+			| __raw_readl(data->ppmu.base + PMCNT_OFFSET(id + 1)));
+	else
+		event = __raw_readl(data->ppmu.base + PMCNT_OFFSET(id));
+
+	dev_dbg(&edev->dev, "%s (event: %lld/%lld)\n",
+				edev->desc->name, event, *total_event);
+
+	return event;
+}
+
+static struct devfreq_event_ops exynos_ppmu_ops = {
+	.set_event = exynos_ppmu_set_event,
+	.get_event = exynos_ppmu_get_event,
+};
+
+static int of_get_devfreq_events(struct device_node *np,
+				 struct exynos_ppmu_data *data)
+{
+	struct devfreq_event_desc *desc;
+	struct device *dev = data->dev;
+	struct device_node *events_np, *node;
+	int i, j, count;
+
+	events_np = of_get_child_by_name(np, "events");
+	if (!events_np) {
+		dev_err(dev,
+			"failed to get child node of devfreq-event devices\n");
+		return -EINVAL;
+	}
+
+	count = of_get_child_count(events_np);
+	desc = devm_kzalloc(dev, sizeof(*desc) * count, GFP_KERNEL);
+	if (!desc)
+		return -ENOMEM;
+	data->num_events = count;
+
+	j = 0;
+	for_each_child_of_node(events_np, node) {
+		for (i = 0; i < ARRAY_SIZE(ppmu_events); i++) {
+			if (!of_node_cmp(node->name, ppmu_events[i].name))
+				break;
+		}
+
+		if (i == ARRAY_SIZE(ppmu_events)) {
+			dev_warn(dev,
+				"don't know how to configure events : %s\n",
+				node->name);
+			continue;
+		}
+
+		desc[j].ops = &exynos_ppmu_ops;
+		desc[j].driver_data = data;
+		desc[j].type |= DEVFREQ_EVENT_TYPE_RAW_DATA;
+
+		of_property_read_string(node, "event-name", &desc[j].name);
+
+		j++;
+
+		of_node_put(node);
+	}
+	data->desc = desc;
+
+	of_node_put(events_np);
+
+	return 0;
+}
+
+static int exynos_ppmu_parse_dt(struct exynos_ppmu_data *data)
+{
+	struct device *dev = data->dev;
+	struct device_node *np = dev->of_node;
+	int ret = 0;
+
+	if (!np) {
+		dev_err(dev, "failed to find devicetree node\n");
+		return -EINVAL;
+	}
+
+	/* Maps the memory mapped IO to control PPMU register */
+	data->ppmu.base = of_iomap(np, 0);
+	if (IS_ERR_OR_NULL(data->ppmu.base)) {
+		dev_err(dev, "failed to map memory region\n");
+		return -EINVAL;
+	}
+
+	data->clk_ppmu = devm_clk_get(dev, "ppmu");
+	if (IS_ERR(data->clk_ppmu)) {
+		data->clk_ppmu = NULL;
+		dev_warn(dev, "failed to get PPMU clock\n");
+	}
+
+	ret = of_get_devfreq_events(np, data);
+	if (ret < 0) {
+		dev_err(dev, "failed to parse exynos ppmu dt node\n");
+		goto err;
+	}
+
+	return 0;
+
+err:
+	iounmap(data->ppmu.base);
+
+	return ret;
+}
+
+static int exynos_ppmu_probe(struct platform_device *pdev)
+{
+	struct exynos_ppmu_data *data;
+	struct devfreq_event_dev **edev;
+	struct devfreq_event_desc *desc;
+	int i, ret = 0, size;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	mutex_init(&data->lock);
+	data->dev = &pdev->dev;
+
+	/* Parse dt data to get resource */
+	ret = exynos_ppmu_parse_dt(data);
+	if (ret < 0) {
+		dev_err(&pdev->dev,
+			"failed to parse devicetree for resource\n");
+		return ret;
+	}
+	desc = data->desc;
+
+	size = sizeof(struct devfreq_event_dev *) * data->num_events;
+	data->edev = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
+	if (!data->edev) {
+		dev_err(&pdev->dev,
+			"failed to allocate memory devfreq-event devices\n");
+		return -ENOMEM;
+	}
+	edev = data->edev;
+	platform_set_drvdata(pdev, data);
+
+	for (i = 0; i < data->num_events; i++) {
+		edev[i] = devfreq_event_add_edev(&pdev->dev, &desc[i]);
+		if (IS_ERR(edev)) {
+			ret = PTR_ERR(edev);
+			dev_err(&pdev->dev,
+				"failed to add devfreq-event device\n");
+			goto err;
+		}
+	}
+
+	clk_prepare_enable(data->clk_ppmu);
+
+	return 0;
+err:
+	iounmap(data->ppmu.base);
+
+	return ret;
+}
+
+static int exynos_ppmu_remove(struct platform_device *pdev)
+{
+	struct exynos_ppmu_data *data = platform_get_drvdata(pdev);
+	int i, ret = 0;
+
+	for (i = 0; i < data->num_events; i++) {
+		ret = devfreq_event_remove_edev(data->edev[i]);
+		if (ret < 0) {
+			dev_err(&pdev->dev,
+				"failed to remove devfreq-event device\n");
+			goto err;
+		}
+	}
+
+err:
+	clk_disable_unprepare(data->clk_ppmu);
+	iounmap(data->ppmu.base);
+
+	return ret;
+}
+
+static struct of_device_id exynos_ppmu_id_match[] = {
+	{ .compatible = "samsung,exynos-ppmu", },
+	{ /* sentinel */ },
+};
+
+static struct platform_driver exynos_ppmu_driver = {
+	.probe	= exynos_ppmu_probe,
+	.remove	= exynos_ppmu_remove,
+	.driver = {
+		.name	= "exynos-ppmu",
+		.owner	= THIS_MODULE,
+		.of_match_table = exynos_ppmu_id_match,
+	},
+};
+module_platform_driver(exynos_ppmu_driver);
+
+MODULE_DESCRIPTION("Exynos PPMU(Performance Profiling Monitoring Unit) driver");
+MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:exynos-ppmu");
-- 
1.8.5.5

[RFC PATCHv3 4/7] devfreq: event: Add documentation for exynos-ppmu devfreq-event driver

[Chanwoo Choi]

This patch adds the documentation for Exynos PPMU (Performance Profiling
Monitoring Unit) devfreq-event driver.

Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 .../bindings/devfreq/event/exynos-ppmu.txt         | 56 ++++++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt

diff --git a/Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt b/Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt
new file mode 100644
index 0000000..f7e50e5
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/event/exynos-ppmu.txt
@@ -0,0 +1,56 @@
+
+* Samsung Exynos PPMU (Performance Profiling Monitoring Unit) device
+
+The Samsung Exynos SoC have PPMU (Performance Profiling Monitoring Unit) for
+each IPs. PPMU provides the primitive values to get performance data. These
+events provide useful information about the behavior of the SoC that you can
+use when analyzing system performance, and made visible and can be counted
+using login in each IP (DMC, CPU, RIGHTBUS, LEFTBUS, CAM interface, LCD, G3D,
+MFC). The Exynos PPMU driver use the devfreq-event class to provide event data
+to various devfreq device. The devfreq device would use the event data when
+derterming the current state of each IP.
+
+Required properties:
+- compatible: Should be "samsung,exynos-ppmu".
+- reg: physical base address of each PPMU and length of memory mapped region.
+
+Optional properties:
+- clock-names : the name of clock used by the PPMU, "ppmu"
+- clocks : phandles for clock specified in "clock-names" property
+- #clock-cells: should be 1.
+
+Example : Examples of PPMU nodes are listed below.
+
+		ppmu_dmc0: ppmu_dmc0@106a0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x106a0000 0x2000>;
+			status = "disabled";
+		};
+
+		ppmu_dmc1: ppmu_dmc1@106b0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x106b0000 0x2000>;
+			status = "disabled";
+		};
+
+		ppmu_cpu: ppmu_cpu@106c0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x106c0000 0x2000>;
+			status = "disabled";
+		};
+
+		ppmu_rightbus: ppmu_rightbus@112a0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x112a0000 0x2000>;
+			clocks = <&cmu CLK_PPMURIGHT>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
+
+		ppmu_leftbus: ppmu_leftbus0@116a0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x116a0000 0x2000>;
+			clocks = <&cmu CLK_PPMULEFT>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
-- 
1.8.5.5

[RFC PATCHv3 5/7] ARM: dts: Add PPMU dt node for Exynos3250

[Chanwoo Choi]

This patch add PPMU (Performance Profiling Monitoring Units) dt node
to estimate the utilization of each IP in Exynos SoC throught DEVFREQ Event
subsystem.

This patch adds following PPMU dt nodes:
- PPMU_DMC0	0x106a0000
- PPMU_DMC1	0x106b0000
- PPMU_RIGHTBUS 0x112A0000
- PPMU_LEFTBUS  0x116A0000
- PPMU_CAMIF    0x11AC0000
- PPMU_LCD0     0x11E40000
- PPMU_3D       0x13220000
- PPMU_MFC_L    0x13660000
- PPMU_CPU	0x106c0000

Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 arch/arm/boot/dts/exynos3250.dtsi | 66 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/arch/arm/boot/dts/exynos3250.dtsi b/arch/arm/boot/dts/exynos3250.dtsi
index c743f60..70a9120 100644
--- a/arch/arm/boot/dts/exynos3250.dtsi
+++ b/arch/arm/boot/dts/exynos3250.dtsi
@@ -529,6 +529,72 @@
 			compatible = "arm,cortex-a7-pmu";
 			interrupts = <0 18 0>, <0 19 0>;
 		};
+
+		ppmu_dmc0: ppmu_dmc0@106a0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x106a0000 0x2000>;
+			status = "disabled";
+		};
+
+		ppmu_dmc1: ppmu_dmc1@106b0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x106b0000 0x2000>;
+			status = "disabled";
+		};
+
+		ppmu_cpu: ppmu_cpu@106c0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x106c0000 0x2000>;
+			status = "disabled";
+		};
+
+		ppmu_rightbus: ppmu_rightbus@112a0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x112a0000 0x2000>;
+			clocks = <&cmu CLK_PPMURIGHT>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
+
+		ppmu_leftbus: ppmu_leftbus0@116a0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x116a0000 0x2000>;
+			clocks = <&cmu CLK_PPMULEFT>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
+
+		ppmu_camif: ppmu_camif@11ac0000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x11ac0000 0x2000>;
+			clocks = <&cmu CLK_PPMUCAMIF>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
+
+		ppmu_lcd0: ppmu_lcd0@11e40000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x11e40000 0x2000>;
+			clocks = <&cmu CLK_PPMULCD0>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
+
+		ppmu_g3d: ppmu_g3d@13220000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x13220000 0x2000>;
+			clocks = <&cmu CLK_PPMUG3D>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
+
+		ppmu_mfc_l: ppmu_mfc_l@13660000 {
+			compatible = "samsung,exynos-ppmu";
+			reg = <0x13660000 0x2000>;
+			clocks = <&cmu CLK_PPMUMFC_L>;
+			clock-names = "ppmu";
+			status = "disabled";
+		};
 	};
 };
 
-- 
1.8.5.5

[RFC PATCHv3 6/7] ARM: dts: Add PPMU dt node for Exynos4 SoC

[Chanwoo Choi]

This patch add PPMU (Performance Profiling Monitoring Unit) dt node for Exynos4
(Exynos4210/4212/4412) SoC. PPMU dt node is used to monitor the utilization of
each IP.

The Exynos4210/Exynos4212/Exynos4412 SoC includes following PPMUs:
- PPMU_DMC0      0x106A_0000
- PPMU_DMC1      0x106B_0000
- PPMU_CPU       0x106C_0000
- PPMU_ACP       0x10AE_0000
- PPMU_RIGHT_BUS 0x112A_0000
- PPMU_LEFT_BUS  0x116A_0000
- PPMU_LCD0      0x11E4_0000
- PPMU_CAMIF     0x11AC_0000
- PPMU_IMAGE     0x12AA_0000
- PPMU_TV        0x12E4_0000
- PPMU_3D        0x1322_0000
- PPMU_MFC_L     0x1366_0000
- PPMU_MFC_R     0x1367_0000

Additionally, the Exynos4210 SoC includes following PPMUs:
- PPMU_LCD1      0x1224_0000

Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
---
 arch/arm/boot/dts/exynos4.dtsi    | 96 +++++++++++++++++++++++++++++++++++++++
 arch/arm/boot/dts/exynos4210.dtsi |  8 ++++
 2 files changed, 104 insertions(+)

diff --git a/arch/arm/boot/dts/exynos4.dtsi b/arch/arm/boot/dts/exynos4.dtsi
index e0278ec..150bb56 100644
--- a/arch/arm/boot/dts/exynos4.dtsi
+++ b/arch/arm/boot/dts/exynos4.dtsi
@@ -645,4 +645,100 @@
 		samsung,sysreg = <&sys_reg>;
 		status = "disabled";
 	};
+
+	ppmu_dmc0: ppmu_dmc0@106a0000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x106a0000 0x2000>;
+		clocks = <&clock CLK_PPMUDMC0>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_dmc1: ppmu_dmc1@106b0000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x106b0000 0x2000>;
+		clocks = <&clock CLK_PPMUDMC1>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_cpu: ppmu_cpu@106c0000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x106c0000 0x2000>;
+		clocks = <&clock CLK_PPMUCPU>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_rightbus: ppmu_rightbus@112a0000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x112a0000 0x2000>;
+		clocks = <&clock CLK_PPMURIGHT>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_leftbus: ppmu_leftbus0@116a0000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x116a0000 0x2000>;
+		clocks = <&clock CLK_PPMULEFT>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_camif: ppmu_camif@11ac0000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x11ac0000 0x2000>;
+		clocks = <&clock CLK_PPMUCAMIF>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_lcd0: ppmu_lcd0@11e40000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x11e40000 0x2000>;
+		clocks = <&clock CLK_PPMULCD0>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_image: ppmu_image@12aa0000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x12aa0000 0x2000>;
+		clocks = <&clock CLK_PPMUIMAGE>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_tv: ppmu_tv@12e40000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x12e40000 0x2000>;
+		clocks = <&clock CLK_PPMUTV>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_g3d: ppmu_g3d@13220000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x13220000 0x2000>;
+		clocks = <&clock CLK_PPMUG3D>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_mfc_l: ppmu_mfc_l@13660000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x13660000 0x2000>;
+		clocks = <&clock CLK_PPMUMFC_L>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
+
+	ppmu_mfc_r: ppmu_mfc_r@13670000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x13670000 0x2000>;
+		clocks = <&clock CLK_PPMUMFC_R>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
 };
diff --git a/arch/arm/boot/dts/exynos4210.dtsi b/arch/arm/boot/dts/exynos4210.dtsi
index bcc9e63..b2598de 100644
--- a/arch/arm/boot/dts/exynos4210.dtsi
+++ b/arch/arm/boot/dts/exynos4210.dtsi
@@ -192,4 +192,12 @@
 			samsung,lcd-wb;
 		};
 	};
+
+	ppmu_lcd1: ppmu_lcd1@12240000 {
+		compatible = "samsung,exynos-ppmu";
+		reg = <0x12240000 0x2000>;
+		clocks = <&clock CLK_PPMULCD1>;
+		clock-names = "ppmu";
+		status = "disabled";
+	};
 };
-- 
1.8.5.5

[RFC PATCHv3 7/7] ARM: dts: exynos: Add PPMU dt node to Exynos3250-based Rinato board

[Chanwoo Choi]

This patch add PPMU dt node to Exynos3250-base Rinato board. The PPMU dt node
is used to get the utilization of DMC0/DMC1/LEFTBUS/RIGHTBUS Block.

Cc: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
---
 arch/arm/boot/dts/exynos3250-rinato.dts | 40 +++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/arch/arm/boot/dts/exynos3250-rinato.dts b/arch/arm/boot/dts/exynos3250-rinato.dts
index 7789442..2888098 100644
--- a/arch/arm/boot/dts/exynos3250-rinato.dts
+++ b/arch/arm/boot/dts/exynos3250-rinato.dts
@@ -542,6 +542,46 @@
 	status = "okay";
 };
 
+&ppmu_dmc0 {
+	status = "okay";
+
+	events {
+		ppmu_dmc0_3: ppmu-dmc0-pmcnt3 {
+			event-name = "ppmu-dmc0-pmcnt3";
+		};
+	};
+};
+
+&ppmu_dmc1 {
+	status = "okay";
+
+	events {
+		ppmu_dmc1_3: ppmu-dmc1-pmcnt3 {
+			event-name = "ppmu-dmc1-pmcnt3";
+		};
+	};
+};
+
+&ppmu_leftbus {
+	status = "okay";
+
+	events {
+		ppmu_leftbus_3: ppmu-leftbus-pmcnt3 {
+			event-name = "ppmu-leftbus-pmcnt3";
+		};
+	};
+};
+
+&ppmu_rightbus {
+	status = "okay";
+
+	events {
+		ppmu_rightbus_3: ppmu-rightbus-pmcnt3 {
+			event-name = "ppmu-rightbus-pmcnt3";
+		};
+	};
+};
+
 &xusbxti {
 	clock-frequency = <24000000>;
 };
-- 
1.8.5.5

Re: [RFC PATCHv3 1/7] devfreq: event: Add new devfreq_event class to provide basic data for devfreq governor

[Krzysztof Kozlowski]

On pią, 2014-12-12 at 17:27 +0900, Chanwoo Choi wrote:
> This patch add new devfreq_event class for devfreq_event device which provide
> raw data (e.g., memory bus utilization/GPU utilization). This raw data from
> devfreq_event data would be used for the governor of devfreq subsystem.
> - devfreq_event device : Provide raw data for governor of existing devfreq device
> - devfreq device       : Monitor device state and change frequency/voltage of device
>                          using the raw data from devfreq_event device
> 
> The devfreq subsystem support generic DVFS(Dynamic Voltage/Frequency Scaling)
> for Non-CPU Devices. The devfreq device would dertermine current device state
> using various governor (e.g., ondemand, performance, powersave). After completed
> determination of system state, devfreq device would change the frequency/voltage
> of devfreq device according to the result of governor.
> 
> But, devfreq governor must need basic data which indicates current device state.
> Existing devfreq subsystem only consider devfreq device which check current system
> state and determine proper system state using basic data. There is no subsystem
> for device providing basic data to devfreq device.
> 
> The devfreq subsystem must need devfreq_event device(data-provider device) for
> existing devfreq device. So, this patch add new devfreq_event class for
> devfreq_event device which read various basic data(e.g, memory bus utilization,
> GPU utilization) and provide measured data to existing devfreq device through
> standard APIs of devfreq_event class.
> 
> The following description explains the feature of two kind of devfreq class:
> - devfreq class (existing)
>  : devfreq consumer device use raw data from devfreq_event device for
>    determining proper current system state and change voltage/frequency
>    dynamically using various governors.
> 
> - devfreq_event class (new)
>  : Provide measured raw data to devfreq device for governor
> 
> Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

[...]

> +/**
> + * devfreq_event_get_event() - Get event and total_event from devfreq-event dev.
> + * @edev	: the devfreq-event device
> + *
> + * Note that this function get the calculated event data from devfreq-event dev
> + * after stoping the progress of whole sequence of devfreq-event dev. Return
> + * current event data and total_event should be stored in second parameter
> + * (total_event).
> + */
> +u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
> +{

I think this function should return int (0 for success, negative
otherwise) and store the "event" under pointer passed as argument.
Why? Because:
1. error conditions are indicated with 'return 0' but should be 'return
-EINVAL'
2. Exynos-ppmu driver returns -EINVAL.
Checking for error conditions is in such case more complex than it
should.


Best regards,
Krzysztof

Re: [RFC PATCHv3 2/7] devfreq: event: Add the list of supported devfreq-event type

[Krzysztof Kozlowski]

On pią, 2014-12-12 at 17:27 +0900, Chanwoo Choi wrote:
> This patch adds the list of supported devfreq-event type as following.
> Each devfreq-event device driver would support the various devfreq-event type
> for devfreq governor at the same time.
> - DEVFREQ_EVENT_TYPE_RAW_DATA
> - DEVFREQ_EVENT_TYPE_UTILIZATION
> - DEVFREQ_EVENT_TYPE_BANDWIDTH
> - DEVFREQ_EVENT_TYPE_LATENCY
> 
> Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> ---
>  drivers/devfreq/devfreq-event.c | 44 +++++++++++++++++++++++++++++++++++++----
>  include/linux/devfreq.h         | 29 ++++++++++++++++++++++-----
>  2 files changed, 64 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/devfreq/devfreq-event.c b/drivers/devfreq/devfreq-event.c
> index eaf59c1..9444f93 100644
> --- a/drivers/devfreq/devfreq-event.c
> +++ b/drivers/devfreq/devfreq-event.c
> @@ -29,6 +29,9 @@
>  #include <linux/of.h>
>  #include "governor.h"
>  
> +#define EVENT_TYPE_RAW_DATA_MAX		U64_MAX
> +#define EVENT_TYPE_UTILIZATION_MAX	100
> +
>  static struct class *devfreq_event_class;
>  
>  /* The list of all devfreq event list */
> @@ -144,7 +147,8 @@ EXPORT_SYMBOL_GPL(devfreq_event_is_enabled);
>   * Note that this function set the event to the devfreq-event device to start
>   * for getting the event data which could be various event type.
>   */
> -int devfreq_event_set_event(struct devfreq_event_dev *edev)
> +int devfreq_event_set_event(struct devfreq_event_dev *edev,
> +				enum devfreq_event_type type)
>  {
>  	int ret;
>  
> @@ -158,7 +162,15 @@ int devfreq_event_set_event(struct devfreq_event_dev *edev)
>  		return -EPERM;
>  
>  	mutex_lock(&edev->lock);
> -	ret = edev->desc->ops->set_event(edev);
> +
> +	if ((edev->desc->type & type) == 0) {
> +		dev_err(&edev->dev, "unsupported of devfreq-event type\n");
> +		mutex_unlock(&edev->lock);
> +		return -EINVAL;
> +	}
> +
> +	ret = edev->desc->ops->set_event(edev, type);
> +
>  	mutex_unlock(&edev->lock);
>  
>  	return ret;
> @@ -174,7 +186,9 @@ EXPORT_SYMBOL_GPL(devfreq_event_set_event);
>   * current event data and total_event should be stored in second parameter
>   * (total_event).
>   */
> -u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
> +u64 devfreq_event_get_event(struct devfreq_event_dev *edev,
> +				enum devfreq_event_type type,
> +				u64 *total_event)
>  {
>  	u64 event;
>  
> @@ -190,7 +204,27 @@ u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
>  		return 0;
>  
>  	mutex_lock(&edev->lock);
> -	event = edev->desc->ops->get_event(edev, total_event);
> +
> +	if ((edev->desc->type & type) == 0) {
> +		dev_err(&edev->dev, "unsupported of devfreq-event type\n");
> +		return -EINVAL;
> +	}
> +
> +	event = edev->desc->ops->get_event(edev, type, total_event);
> +
> +	switch (type) {
> +	case DEVFREQ_EVENT_TYPE_RAW_DATA:
> +	case DEVFREQ_EVENT_TYPE_BANDWIDTH:
> +	case DEVFREQ_EVENT_TYPE_LATENCY:
> +		if ((event > *total_event)
> +			|| ((event > EVENT_TYPE_RAW_DATA_MAX) ||
> +				*total_event > EVENT_TYPE_RAW_DATA_MAX))
> +			event = 0;

missing break here.

Best regards,
Krzysztof

> +	case DEVFREQ_EVENT_TYPE_UTILIZATION:
> +		if (event > EVENT_TYPE_UTILIZATION_MAX)
> +			event = 0;
> +	}
> +
>  	mutex_unlock(&edev->lock);
>  
>  	return event;
> @@ -215,8 +249,10 @@ int devfreq_event_reset_event(struct devfreq_event_dev *edev)
>  		return -EPERM;
>  
>  	mutex_lock(&edev->lock);
> +
>  	if (edev->desc->ops && edev->desc->ops->reset)
>  		ret = edev->desc->ops->reset(edev);
> +
>  	mutex_unlock(&edev->lock);
>  
>  	if (ret < 0)
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index a8d2277..82da235 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -197,6 +197,14 @@ struct devfreq_event_dev {
>  	const struct devfreq_event_desc *desc;
>  };
>  
> +/* The supported type by devfreq-event device */
> +enum devfreq_event_type {
> +	DEVFREQ_EVENT_TYPE_RAW_DATA	= BIT(0),
> +	DEVFREQ_EVENT_TYPE_UTILIZATION	= BIT(1),
> +	DEVFREQ_EVENT_TYPE_BANDWIDTH	= BIT(2),
> +	DEVFREQ_EVENT_TYPE_LATENCY	= BIT(3),
> +};
> +
>  /**
>   * struct devfreq_event_ops - the operations of devfreq-event device
>   *
> @@ -219,8 +227,10 @@ struct devfreq_event_ops {
>  	int (*reset)(struct devfreq_event_dev *event_dev);
>  
>  	/* Mandatory functions */
> -	int (*set_event)(struct devfreq_event_dev *event_dev);
> -	u64 (*get_event)(struct devfreq_event_dev *event_dev, u64 *total_event);
> +	int (*set_event)(struct devfreq_event_dev *event_dev,
> +			enum devfreq_event_type type);
> +	u64 (*get_event)(struct devfreq_event_dev *event_dev,
> +			enum devfreq_event_type type, u64 *total_event);
>  };
>  
>  /**
> @@ -228,6 +238,10 @@ struct devfreq_event_ops {
>   *
>   * @name	: the name of devfreq-event device.
>   * @driver_data	: the private data for devfreq-event driver.
> + * @event_type	: the supported devfreq-event type among as following
> + *		  - DEVFREQ_EVENT_TYPE_UTILIZATION
> + *		  - DEVFREQ_EVENT_TYPE_BANDWIDTH
> + *		  - DEVFREQ_EVENT_TYPE_LATENCY
>   * @ops		: the operation to control devfreq-event device.
>   *
>   * Each devfreq-event device is described with a this structure.
> @@ -236,6 +250,7 @@ struct devfreq_event_ops {
>  struct devfreq_event_desc {
>  	const char *name;
>  	void *driver_data;
> +	enum devfreq_event_type type;
>  
>  	struct devfreq_event_ops *ops;
>  };
> @@ -273,8 +288,10 @@ extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
>  extern int devfreq_event_enable_edev(struct devfreq_event_dev *edev);
>  extern int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
>  extern bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
> -extern int devfreq_event_set_event(struct devfreq_event_dev *edev);
> +extern int devfreq_event_set_event(struct devfreq_event_dev *edev,
> +				enum devfreq_event_type type);
>  extern u64 devfreq_event_get_event(struct devfreq_event_dev *edev,
> +				enum devfreq_event_type type,
>  				u64 *total_event);
>  extern int devfreq_event_reset_event(struct devfreq_event_dev *edev);
>  extern void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev);
> @@ -397,13 +414,15 @@ static inline bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
>  	return false;
>  }
>  
> -static inline int devfreq_event_set_event(struct devfreq_event_dev *edev);
> +static inline int devfreq_event_set_event(struct devfreq_event_dev *edev,
> +					enum devfreq_event_type type)
>  {
>  	return -EINVAL;
>  }
>  
>  static inline u64 devfreq_event_get_event(struct devfreq_event_dev *edev
> -					u64 *total_event);
> +					enum devfreq_event_type type,
> +					u64 *total_event)
>  {
>  	return 0;
>  }

Re: [RFC PATCHv3 2/7] devfreq: event: Add the list of supported devfreq-event type

[Chanwoo Choi]

Hi Krzysztof,

On 12/15/2014 11:53 PM, Krzysztof Kozlowski wrote:
> On pią, 2014-12-12 at 17:27 +0900, Chanwoo Choi wrote:
>> This patch adds the list of supported devfreq-event type as following.
>> Each devfreq-event device driver would support the various devfreq-event type
>> for devfreq governor at the same time.
>> - DEVFREQ_EVENT_TYPE_RAW_DATA
>> - DEVFREQ_EVENT_TYPE_UTILIZATION
>> - DEVFREQ_EVENT_TYPE_BANDWIDTH
>> - DEVFREQ_EVENT_TYPE_LATENCY
>>
>> Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
>> Cc: Kyungmin Park <kyungmin.park@samsung.com>
>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
>> ---
>>  drivers/devfreq/devfreq-event.c | 44 +++++++++++++++++++++++++++++++++++++----
>>  include/linux/devfreq.h         | 29 ++++++++++++++++++++++-----
>>  2 files changed, 64 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/devfreq/devfreq-event.c b/drivers/devfreq/devfreq-event.c
>> index eaf59c1..9444f93 100644
>> --- a/drivers/devfreq/devfreq-event.c
>> +++ b/drivers/devfreq/devfreq-event.c
>> @@ -29,6 +29,9 @@
>>  #include <linux/of.h>
>>  #include "governor.h"
>>  
>> +#define EVENT_TYPE_RAW_DATA_MAX		U64_MAX
>> +#define EVENT_TYPE_UTILIZATION_MAX	100
>> +
>>  static struct class *devfreq_event_class;
>>  
>>  /* The list of all devfreq event list */
>> @@ -144,7 +147,8 @@ EXPORT_SYMBOL_GPL(devfreq_event_is_enabled);
>>   * Note that this function set the event to the devfreq-event device to start
>>   * for getting the event data which could be various event type.
>>   */
>> -int devfreq_event_set_event(struct devfreq_event_dev *edev)
>> +int devfreq_event_set_event(struct devfreq_event_dev *edev,
>> +				enum devfreq_event_type type)
>>  {
>>  	int ret;
>>  
>> @@ -158,7 +162,15 @@ int devfreq_event_set_event(struct devfreq_event_dev *edev)
>>  		return -EPERM;
>>  
>>  	mutex_lock(&edev->lock);
>> -	ret = edev->desc->ops->set_event(edev);
>> +
>> +	if ((edev->desc->type & type) == 0) {
>> +		dev_err(&edev->dev, "unsupported of devfreq-event type\n");
>> +		mutex_unlock(&edev->lock);
>> +		return -EINVAL;
>> +	}
>> +
>> +	ret = edev->desc->ops->set_event(edev, type);
>> +
>>  	mutex_unlock(&edev->lock);
>>  
>>  	return ret;
>> @@ -174,7 +186,9 @@ EXPORT_SYMBOL_GPL(devfreq_event_set_event);
>>   * current event data and total_event should be stored in second parameter
>>   * (total_event).
>>   */
>> -u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
>> +u64 devfreq_event_get_event(struct devfreq_event_dev *edev,
>> +				enum devfreq_event_type type,
>> +				u64 *total_event)
>>  {
>>  	u64 event;
>>  
>> @@ -190,7 +204,27 @@ u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
>>  		return 0;
>>  
>>  	mutex_lock(&edev->lock);
>> -	event = edev->desc->ops->get_event(edev, total_event);
>> +
>> +	if ((edev->desc->type & type) == 0) {
>> +		dev_err(&edev->dev, "unsupported of devfreq-event type\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	event = edev->desc->ops->get_event(edev, type, total_event);
>> +
>> +	switch (type) {
>> +	case DEVFREQ_EVENT_TYPE_RAW_DATA:
>> +	case DEVFREQ_EVENT_TYPE_BANDWIDTH:
>> +	case DEVFREQ_EVENT_TYPE_LATENCY:
>> +		if ((event > *total_event)
>> +			|| ((event > EVENT_TYPE_RAW_DATA_MAX) ||
>> +				*total_event > EVENT_TYPE_RAW_DATA_MAX))
>> +			event = 0;
> 
> missing break here.

My mistake. I'll add it and 'default' case statement.

Best Regards,
Chanwoo Choi

Re: [RFC PATCHv3 1/7] devfreq: event: Add new devfreq_event class to provide basic data for devfreq governor

[Chanwoo Choi]

Hi Krzysztof,

On 12/15/2014 11:53 PM, Krzysztof Kozlowski wrote:
> On pią, 2014-12-12 at 17:27 +0900, Chanwoo Choi wrote:
>> This patch add new devfreq_event class for devfreq_event device which provide
>> raw data (e.g., memory bus utilization/GPU utilization). This raw data from
>> devfreq_event data would be used for the governor of devfreq subsystem.
>> - devfreq_event device : Provide raw data for governor of existing devfreq device
>> - devfreq device       : Monitor device state and change frequency/voltage of device
>>                          using the raw data from devfreq_event device
>>
>> The devfreq subsystem support generic DVFS(Dynamic Voltage/Frequency Scaling)
>> for Non-CPU Devices. The devfreq device would dertermine current device state
>> using various governor (e.g., ondemand, performance, powersave). After completed
>> determination of system state, devfreq device would change the frequency/voltage
>> of devfreq device according to the result of governor.
>>
>> But, devfreq governor must need basic data which indicates current device state.
>> Existing devfreq subsystem only consider devfreq device which check current system
>> state and determine proper system state using basic data. There is no subsystem
>> for device providing basic data to devfreq device.
>>
>> The devfreq subsystem must need devfreq_event device(data-provider device) for
>> existing devfreq device. So, this patch add new devfreq_event class for
>> devfreq_event device which read various basic data(e.g, memory bus utilization,
>> GPU utilization) and provide measured data to existing devfreq device through
>> standard APIs of devfreq_event class.
>>
>> The following description explains the feature of two kind of devfreq class:
>> - devfreq class (existing)
>>  : devfreq consumer device use raw data from devfreq_event device for
>>    determining proper current system state and change voltage/frequency
>>    dynamically using various governors.
>>
>> - devfreq_event class (new)
>>  : Provide measured raw data to devfreq device for governor
>>
>> Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
>> Cc: Kyungmin Park <kyungmin.park@samsung.com>
>> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> 
> [...]
> 
>> +/**
>> + * devfreq_event_get_event() - Get event and total_event from devfreq-event dev.
>> + * @edev	: the devfreq-event device
>> + *
>> + * Note that this function get the calculated event data from devfreq-event dev
>> + * after stoping the progress of whole sequence of devfreq-event dev. Return
>> + * current event data and total_event should be stored in second parameter
>> + * (total_event).
>> + */
>> +u64 devfreq_event_get_event(struct devfreq_event_dev *edev, u64 *total_event)
>> +{
> 
> I think this function should return int (0 for success, negative
> otherwise) and store the "event" under pointer passed as argument.
> Why? Because:
> 1. error conditions are indicated with 'return 0' but should be 'return
> -EINVAL'
> 2. Exynos-ppmu driver returns -EINVAL.
> Checking for error conditions is in such case more complex than it
> should.

In this patchset,
the return value (event) and *total_event of devfreq_event_get_event() should
be used for busy_time/total_time of struct devfreq_dev_status (include/linux/devfreq.h).
The busy_time/total_time is 'unsigned long' type.

So, I'll modify the prototype of devfreq_event_get_event() as following by adding
new 'devfreq_event_data' structure.

struct devfreq_event_data {
	u64 event;
	u64 total_event;
};

int devfreq_event_get_event(struct devfreq_event_edev *edev, struct devfreq_event_data *edata);

Best Regards,
Chanwoo Choi