[PATCH v2 0/8] RFC: CPU frequency min/max as PM QoS params

[PATCH v2 0/8] RFC: CPU frequency min/max as PM QoS params

[Antti P Miettinen]

The inspiration for this patch series is the N9 CPU frequency boost
upon input events:

http://www.spinics.net/lists/cpufreq/msg00667.html

and the related changes in git://codeaurora.org/kernel/msm.git tree.
Those patches modify the ondemand cpufreq governor. This patch series
adds minimum and maximum CPU frequency as PM QoS parameters and
modifies the cpufreq core to enforce the PM QoS limits. There is also
an example module for boosting the frequency upon input events.

I've been testing these changes against Ubuntu 3.2 kernel on a Dell
E6420 with the ACPI cpufreq driver. The patches are against
linux-next/master, compile tested against it.

V2:
* split min and max to separate commits
* handle PM QoS min above max as max
* handle PM QoS max below min as min

	--Antti

Alex Frid (1):
  PM QoS: Simplify PM QoS expansion/merge

Antti P Miettinen (7):
  PM QoS: Add CPU frequency minimum as PM QoS param
  cpufreq: Export user_policy min/max
  cpufreq: Preserve sysfs min/max request
  cpufreq: Enforce PM QoS minimum limit
  input: CPU frequency booster
  PM QoS: Add CPU frequency maximum as PM QoS param
  cpufreq: Enforce PM QoS maximum frequency

 drivers/cpufreq/cpufreq.c     |   59 +++++++++++++-
 drivers/input/Kconfig         |    9 ++
 drivers/input/Makefile        |    1 +
 drivers/input/input-cfboost.c |  174 +++++++++++++++++++++++++++++++++++++++++
 include/linux/pm_qos.h        |   19 ++++-
 kernel/power/qos.c            |   55 ++++++++++----
 6 files changed, 295 insertions(+), 22 deletions(-)
 create mode 100644 drivers/input/input-cfboost.c

-- 
1.7.4.1

[PATCH v2 1/8] PM QoS: Simplify PM QoS expansion/merge

[Antti P Miettinen]

From: Alex Frid <afrid@nvidia.com>

- Replace class ID #define with enumeration
- Loop through PM QoS objects during initialization (rather than
  initializing them one-by-one)

Signed-off-by: Alex Frid <afrid@nvidia.com>
Reviewed-by: Antti Miettinen <amiettinen@nvidia.com>
Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com>
Reviewed-by: Scott Williams <scwilliams@nvidia.com>
Reviewed-by: Yu-Huan Hsu <yhsu@nvidia.com>
---
 include/linux/pm_qos.h |   14 +++++++++-----
 kernel/power/qos.c     |   23 ++++++++++-------------
 2 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index e5bbcba..5ac91d8 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -9,12 +9,16 @@
 #include <linux/miscdevice.h>
 #include <linux/device.h>
 
-#define PM_QOS_RESERVED 0
-#define PM_QOS_CPU_DMA_LATENCY 1
-#define PM_QOS_NETWORK_LATENCY 2
-#define PM_QOS_NETWORK_THROUGHPUT 3
+enum {
+	PM_QOS_RESERVED = 0,
+	PM_QOS_CPU_DMA_LATENCY,
+	PM_QOS_NETWORK_LATENCY,
+	PM_QOS_NETWORK_THROUGHPUT,
+
+	/* insert new class ID */
+	PM_QOS_NUM_CLASSES,
+};
 
-#define PM_QOS_NUM_CLASSES 4
 #define PM_QOS_DEFAULT_VALUE -1
 
 #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE	(2000 * USEC_PER_SEC)
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 995e3bd..d6d6dbd 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -469,21 +469,18 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
 static int __init pm_qos_power_init(void)
 {
 	int ret = 0;
+	int i;
 
-	ret = register_pm_qos_misc(&cpu_dma_pm_qos);
-	if (ret < 0) {
-		printk(KERN_ERR "pm_qos_param: cpu_dma_latency setup failed\n");
-		return ret;
-	}
-	ret = register_pm_qos_misc(&network_lat_pm_qos);
-	if (ret < 0) {
-		printk(KERN_ERR "pm_qos_param: network_latency setup failed\n");
-		return ret;
+	BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES);
+
+	for (i = 1; i < PM_QOS_NUM_CLASSES; i++) {
+		ret = register_pm_qos_misc(pm_qos_array[i]);
+		if (ret < 0) {
+			printk(KERN_ERR "pm_qos_param: %s setup failed\n",
+			       pm_qos_array[i]->name);
+			return ret;
+		}
 	}
-	ret = register_pm_qos_misc(&network_throughput_pm_qos);
-	if (ret < 0)
-		printk(KERN_ERR
-			"pm_qos_param: network_throughput setup failed\n");
 
 	return ret;
 }
-- 
1.7.4.1

[PATCH v2 2/8] PM QoS: Add CPU frequency minimum as PM QoS param

[Antti P Miettinen]

Add minimum CPU frequency as PM QoS parameter.

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 include/linux/pm_qos.h |    3 +++
 kernel/power/qos.c     |   17 ++++++++++++++++-
 2 files changed, 19 insertions(+), 1 deletions(-)

diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 5ac91d8..54a0d00 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -14,8 +14,10 @@ enum {
 	PM_QOS_CPU_DMA_LATENCY,
 	PM_QOS_NETWORK_LATENCY,
 	PM_QOS_NETWORK_THROUGHPUT,
+	PM_QOS_CPU_FREQ_MIN,
 
 	/* insert new class ID */
+
 	PM_QOS_NUM_CLASSES,
 };
 
@@ -25,6 +27,7 @@ enum {
 #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE	(2000 * USEC_PER_SEC)
 #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE	0
 #define PM_QOS_DEV_LAT_DEFAULT_VALUE		0
+#define PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE	0
 
 struct pm_qos_request {
 	struct plist_node node;
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index d6d6dbd..07d761a 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -101,11 +101,26 @@ static struct pm_qos_object network_throughput_pm_qos = {
 };
 
 
+static BLOCKING_NOTIFIER_HEAD(cpu_freq_min_notifier);
+static struct pm_qos_constraints cpu_freq_min_constraints = {
+	.list = PLIST_HEAD_INIT(cpu_freq_min_constraints.list),
+	.target_value = PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE,
+	.default_value = PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE,
+	.type = PM_QOS_MAX,
+	.notifiers = &cpu_freq_min_notifier,
+};
+static struct pm_qos_object cpu_freq_min_pm_qos = {
+	.constraints = &cpu_freq_min_constraints,
+	.name = "cpu_freq_min",
+};
+
+
 static struct pm_qos_object *pm_qos_array[] = {
 	&null_pm_qos,
 	&cpu_dma_pm_qos,
 	&network_lat_pm_qos,
-	&network_throughput_pm_qos
+	&network_throughput_pm_qos,
+	&cpu_freq_min_pm_qos,
 };
 
 static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
-- 
1.7.4.1

[PATCH v2 3/8] cpufreq: Export user_policy min/max

[Antti P Miettinen]

Add sysfs nodes for user_policy min and max settings.

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 drivers/cpufreq/cpufreq.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 622013f..f115888 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -363,6 +363,8 @@ show_one(cpuinfo_transition_latency, cpuinfo.transition_latency);
 show_one(scaling_min_freq, min);
 show_one(scaling_max_freq, max);
 show_one(scaling_cur_freq, cur);
+show_one(policy_min_freq, user_policy.min);
+show_one(policy_max_freq, user_policy.max);
 
 static int __cpufreq_set_policy(struct cpufreq_policy *data,
 				struct cpufreq_policy *policy);
@@ -581,6 +583,8 @@ cpufreq_freq_attr_rw(scaling_min_freq);
 cpufreq_freq_attr_rw(scaling_max_freq);
 cpufreq_freq_attr_rw(scaling_governor);
 cpufreq_freq_attr_rw(scaling_setspeed);
+cpufreq_freq_attr_ro(policy_min_freq);
+cpufreq_freq_attr_ro(policy_max_freq);
 
 static struct attribute *default_attrs[] = {
 	&cpuinfo_min_freq.attr,
@@ -594,6 +598,8 @@ static struct attribute *default_attrs[] = {
 	&scaling_driver.attr,
 	&scaling_available_governors.attr,
 	&scaling_setspeed.attr,
+	&policy_min_freq.attr,
+	&policy_max_freq.attr,
 	NULL
 };
 
-- 
1.7.4.1

[PATCH v2 4/8] cpufreq: Preserve sysfs min/max request

[Antti P Miettinen]

Store the value received via sysfs as the user_policy
min/max value instead of the currently enforced min/max.
This allows restoring the user min/max values when
constraints on enforced min/max change.

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 drivers/cpufreq/cpufreq.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index f115888..127e37a 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -388,7 +388,7 @@ static ssize_t store_##file_name					\
 		return -EINVAL;						\
 									\
 	ret = __cpufreq_set_policy(policy, &new_policy);		\
-	policy->user_policy.object = policy->object;			\
+	policy->user_policy.object = new_policy.object;			\
 									\
 	return ret ? ret : count;					\
 }
-- 
1.7.4.1

[PATCH v2 5/8] cpufreq: Enforce PM QoS minimum limit

[Antti P Miettinen]

Observe PM QoS CPU frequency minimum in addition
to policy settings.

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 drivers/cpufreq/cpufreq.c |   41 +++++++++++++++++++++++++++++++++++++++--
 1 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 127e37a..c2c1c62 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -29,6 +29,7 @@
 #include <linux/completion.h>
 #include <linux/mutex.h>
 #include <linux/syscore_ops.h>
+#include <linux/pm_qos.h>
 
 #include <trace/events/power.h>
 
@@ -1633,9 +1634,16 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
 				struct cpufreq_policy *policy)
 {
 	int ret = 0;
+	unsigned int pmin = policy->min;
+	unsigned int pmax = policy->max;
+	unsigned int qmin = min(pm_qos_request(PM_QOS_CPU_FREQ_MIN),
+				data->max);
 
-	pr_debug("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
-		policy->min, policy->max);
+	pr_debug("setting new policy for CPU %u: %u/%u - %u kHz\n",
+		 policy->cpu, pmin, qmin, pmax);
+
+	/* clamp the new policy to PM QoS limits */
+	policy->min = max(pmin, qmin);
 
 	memcpy(&policy->cpuinfo, &data->cpuinfo,
 				sizeof(struct cpufreq_cpuinfo));
@@ -1710,6 +1718,9 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
 	}
 
 error_out:
+	/* restore the limits that the policy requested */
+	policy->min = pmin;
+	policy->max = pmax;
 	return ret;
 }
 
@@ -1903,9 +1914,32 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver)
 }
 EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
 
+static int cpu_freq_notify(struct notifier_block *b,
+			   unsigned long l, void *v);
+
+static struct notifier_block min_freq_notifier = {
+	.notifier_call = cpu_freq_notify,
+};
+
+static int cpu_freq_notify(struct notifier_block *b,
+			   unsigned long l, void *v)
+{
+	int cpu;
+	pr_debug("PM QoS min %lu\n", l);
+	for_each_online_cpu(cpu) {
+		struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+		if (policy) {
+			cpufreq_update_policy(policy->cpu);
+			cpufreq_cpu_put(policy);
+		}
+	}
+	return NOTIFY_OK;
+}
+
 static int __init cpufreq_core_init(void)
 {
 	int cpu;
+	int rc;
 
 	for_each_possible_cpu(cpu) {
 		per_cpu(cpufreq_policy_cpu, cpu) = -1;
@@ -1915,6 +1949,9 @@ static int __init cpufreq_core_init(void)
 	cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj);
 	BUG_ON(!cpufreq_global_kobject);
 	register_syscore_ops(&cpufreq_syscore_ops);
+	rc = pm_qos_add_notifier(PM_QOS_CPU_FREQ_MIN,
+				 &min_freq_notifier);
+	BUG_ON(rc);
 
 	return 0;
 }
-- 
1.7.4.1

[PATCH v2 6/8] input: CPU frequency booster

[Antti P Miettinen]

Inspired by cpufreq ondemand governor changes at
git://codeaurora.org/kernel/msm.git tree in commits:

    2a6181bc76c6ce46ca0fa8e547be42acd534cf0e
    1cca8861d8fda4e05f6b0c59c60003345c15454d
    96a9aeb02bf5b3fbbef47e44460750eb275e9f1b
    b600449501cf15928440f87eff86b1f32d14214e
    88a65c7ae04632ffee11f9fc628d7ab017c06b83

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 drivers/input/Kconfig         |    9 ++
 drivers/input/Makefile        |    1 +
 drivers/input/input-cfboost.c |  174 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 184 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/input-cfboost.c

diff --git a/drivers/input/Kconfig b/drivers/input/Kconfig
index 001b147..3859f78 100644
--- a/drivers/input/Kconfig
+++ b/drivers/input/Kconfig
@@ -161,6 +161,15 @@ config INPUT_APMPOWER
 	  To compile this driver as a module, choose M here: the
 	  module will be called apm-power.
 
+config INPUT_CFBOOST
+	tristate "CPU frequency booster"
+	depends on INPUT && CPU_FREQ
+	help
+	  Say Y here if you want to boost frequency upon input events;
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called input-cfboost.
+
 comment "Input Device Drivers"
 
 source "drivers/input/keyboard/Kconfig"
diff --git a/drivers/input/Makefile b/drivers/input/Makefile
index 0c78949..6cad177 100644
--- a/drivers/input/Makefile
+++ b/drivers/input/Makefile
@@ -24,3 +24,4 @@ obj-$(CONFIG_INPUT_TOUCHSCREEN)	+= touchscreen/
 obj-$(CONFIG_INPUT_MISC)	+= misc/
 
 obj-$(CONFIG_INPUT_APMPOWER)	+= apm-power.o
+obj-$(CONFIG_INPUT_CFBOOST)	+= input-cfboost.o
diff --git a/drivers/input/input-cfboost.c b/drivers/input/input-cfboost.c
new file mode 100644
index 0000000..bef3ec5
--- /dev/null
+++ b/drivers/input/input-cfboost.c
@@ -0,0 +1,174 @@
+/*
+ * drivers/input/input-cfboost.c
+ *
+ * Copyright (C) 2012 NVIDIA Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/printk.h>
+#include <linux/workqueue.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/pm_qos.h>
+
+/* This module listens to input events and sets a temporary frequency
+ * floor upon input event detection. This is based on changes to
+ * cpufreq ondemand governor by:
+ *
+ * Tero Kristo <tero.kristo@nokia.com>
+ * Brian Steuer <bsteuer@codeaurora.org>
+ * David Ng <dave@codeaurora.org>
+ *
+ * at git://codeaurora.org/kernel/msm.git tree, commits:
+ *
+ * 2a6181bc76c6ce46ca0fa8e547be42acd534cf0e
+ * 1cca8861d8fda4e05f6b0c59c60003345c15454d
+ * 96a9aeb02bf5b3fbbef47e44460750eb275e9f1b
+ * b600449501cf15928440f87eff86b1f32d14214e
+ * 88a65c7ae04632ffee11f9fc628d7ab017c06b83
+ */
+
+MODULE_AUTHOR("Antti P Miettinen <amiettinen@nvidia.com>");
+MODULE_DESCRIPTION("Input event CPU frequency booster");
+MODULE_LICENSE("GPL v2");
+
+
+static struct pm_qos_request qos_req;
+static struct work_struct boost;
+static struct delayed_work unboost;
+static unsigned int boost_freq; /* kHz */
+module_param(boost_freq, uint, 0644);
+static unsigned long boost_time = 500; /* ms */
+module_param(boost_time, ulong, 0644);
+static struct workqueue_struct *cfb_wq;
+
+static void cfb_boost(struct work_struct *w)
+{
+	cancel_delayed_work_sync(&unboost);
+	pm_qos_update_request(&qos_req, boost_freq);
+	queue_delayed_work(cfb_wq, &unboost, msecs_to_jiffies(boost_time));
+}
+
+static void cfb_unboost(struct work_struct *w)
+{
+	pm_qos_update_request(&qos_req, PM_QOS_DEFAULT_VALUE);
+}
+
+static void cfb_input_event(struct input_handle *handle, unsigned int type,
+			    unsigned int code, int value)
+{
+	if (!work_pending(&boost))
+		queue_work(cfb_wq, &boost);
+}
+
+static int cfb_input_connect(struct input_handler *handler,
+			     struct input_dev *dev,
+			     const struct input_device_id *id)
+{
+	struct input_handle *handle;
+	int error;
+
+	handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
+	if (!handle)
+		return -ENOMEM;
+
+	handle->dev = dev;
+	handle->handler = handler;
+	handle->name = "icfboost";
+
+	error = input_register_handle(handle);
+	if (error)
+		goto err2;
+
+	error = input_open_device(handle);
+	if (error)
+		goto err1;
+
+	return 0;
+err1:
+	input_unregister_handle(handle);
+err2:
+	kfree(handle);
+	return error;
+}
+
+static void cfb_input_disconnect(struct input_handle *handle)
+{
+	input_close_device(handle);
+	input_unregister_handle(handle);
+	kfree(handle);
+}
+
+/* XXX make configurable */
+static const struct input_device_id cfb_ids[] = {
+	{ /* touch screen */
+		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
+				INPUT_DEVICE_ID_MATCH_KEYBIT,
+		.evbit = { BIT_MASK(EV_ABS) },
+		.keybit = {[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
+	},
+	{ /* mouse */
+		.flags = INPUT_DEVICE_ID_MATCH_EVBIT |
+				INPUT_DEVICE_ID_MATCH_KEYBIT,
+		.evbit = { BIT_MASK(EV_REL) },
+		.keybit = {[BIT_WORD(BTN_MOUSE)] = BIT_MASK(BTN_MOUSE) },
+	},
+	{ },
+};
+
+static struct input_handler cfb_input_handler = {
+	.event		= cfb_input_event,
+	.connect	= cfb_input_connect,
+	.disconnect	= cfb_input_disconnect,
+	.name		= "icfboost",
+	.id_table	= cfb_ids,
+};
+
+static int __init cfboost_init(void)
+{
+	int ret;
+
+	cfb_wq = create_workqueue("icfb-wq");
+	if (!cfb_wq)
+		return -ENOMEM;
+	INIT_WORK(&boost, cfb_boost);
+	INIT_DELAYED_WORK(&unboost, cfb_unboost);
+	ret = input_register_handler(&cfb_input_handler);
+	if (ret) {
+		destroy_workqueue(cfb_wq);
+		return ret;
+	}
+	pm_qos_add_request(&qos_req, PM_QOS_CPU_FREQ_MIN,
+			   PM_QOS_DEFAULT_VALUE);
+	return 0;
+}
+
+static void __exit cfboost_exit(void)
+{
+	/* stop input events */
+	input_unregister_handler(&cfb_input_handler);
+	/* cancel pending work requests */
+	cancel_work_sync(&boost);
+	cancel_delayed_work_sync(&unboost);
+	/* clean up */
+	destroy_workqueue(cfb_wq);
+	pm_qos_remove_request(&qos_req);
+}
+
+module_init(cfboost_init);
+module_exit(cfboost_exit);
-- 
1.7.4.1

[PATCH v2 7/8] PM QoS: Add CPU frequency maximum as PM QoS param

[Antti P Miettinen]

Add maximum CPU frequency as PM QoS parameter.

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 include/linux/pm_qos.h |    2 ++
 kernel/power/qos.c     |   15 +++++++++++++++
 2 files changed, 17 insertions(+), 0 deletions(-)

diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 54a0d00..7b8d08b 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -15,6 +15,7 @@ enum {
 	PM_QOS_NETWORK_LATENCY,
 	PM_QOS_NETWORK_THROUGHPUT,
 	PM_QOS_CPU_FREQ_MIN,
+	PM_QOS_CPU_FREQ_MAX,
 
 	/* insert new class ID */
 
@@ -28,6 +29,7 @@ enum {
 #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE	0
 #define PM_QOS_DEV_LAT_DEFAULT_VALUE		0
 #define PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE	0
+#define PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE	LONG_MAX
 
 struct pm_qos_request {
 	struct plist_node node;
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 07d761a..04b744b 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -115,12 +115,27 @@ static struct pm_qos_object cpu_freq_min_pm_qos = {
 };
 
 
+static BLOCKING_NOTIFIER_HEAD(cpu_freq_max_notifier);
+static struct pm_qos_constraints cpu_freq_max_constraints = {
+	.list = PLIST_HEAD_INIT(cpu_freq_max_constraints.list),
+	.target_value = PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE,
+	.default_value = PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE,
+	.type = PM_QOS_MIN,
+	.notifiers = &cpu_freq_max_notifier,
+};
+static struct pm_qos_object cpu_freq_max_pm_qos = {
+	.constraints = &cpu_freq_max_constraints,
+	.name = "cpu_freq_max",
+};
+
+
 static struct pm_qos_object *pm_qos_array[] = {
 	&null_pm_qos,
 	&cpu_dma_pm_qos,
 	&network_lat_pm_qos,
 	&network_throughput_pm_qos,
 	&cpu_freq_min_pm_qos,
+	&cpu_freq_max_pm_qos,
 };
 
 static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
-- 
1.7.4.1

[PATCH v2 8/8] cpufreq: Enforce PM QoS maximum frequency

[Antti P Miettinen]

Observe PM QoS CPU frequency maximum in addition to
policy settings.

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 drivers/cpufreq/cpufreq.c |   16 +++++++++++++---
 1 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index c2c1c62..d233a8b 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1638,12 +1638,15 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
 	unsigned int pmax = policy->max;
 	unsigned int qmin = min(pm_qos_request(PM_QOS_CPU_FREQ_MIN),
 				data->max);
+	unsigned int qmax = max(pm_qos_request(PM_QOS_CPU_FREQ_MAX),
+				data->min);
 
-	pr_debug("setting new policy for CPU %u: %u/%u - %u kHz\n",
-		 policy->cpu, pmin, qmin, pmax);
+	pr_debug("setting new policy for CPU %u: %u/%u - %u/%u kHz\n",
+		 policy->cpu, pmin, qmin, pmax, qmax);
 
 	/* clamp the new policy to PM QoS limits */
 	policy->min = max(pmin, qmin);
+	policy->max = min(pmax, qmax);
 
 	memcpy(&policy->cpuinfo, &data->cpuinfo,
 				sizeof(struct cpufreq_cpuinfo));
@@ -1920,12 +1923,16 @@ static int cpu_freq_notify(struct notifier_block *b,
 static struct notifier_block min_freq_notifier = {
 	.notifier_call = cpu_freq_notify,
 };
+static struct notifier_block max_freq_notifier = {
+	.notifier_call = cpu_freq_notify,
+};
 
 static int cpu_freq_notify(struct notifier_block *b,
 			   unsigned long l, void *v)
 {
 	int cpu;
-	pr_debug("PM QoS min %lu\n", l);
+	pr_debug("PM QoS %s %lu\n",
+		 b == &min_freq_notifier ? "min" : "max", l);
 	for_each_online_cpu(cpu) {
 		struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
 		if (policy) {
@@ -1952,6 +1959,9 @@ static int __init cpufreq_core_init(void)
 	rc = pm_qos_add_notifier(PM_QOS_CPU_FREQ_MIN,
 				 &min_freq_notifier);
 	BUG_ON(rc);
+	rc = pm_qos_add_notifier(PM_QOS_CPU_FREQ_MAX,
+				 &max_freq_notifier);
+	BUG_ON(rc);
 
 	return 0;
 }
-- 
1.7.4.1

Re: [PATCH v2 0/8] RFC: CPU frequency min/max as PM QoS params

[mark gross]

just a quick note: ever since I lost my mgross@linux.intel.com email
I've started using markgross@thegnar.org

On Fri, Jan 13, 2012 at 02:59:11PM +0200, Antti P Miettinen wrote:
> The inspiration for this patch series is the N9 CPU frequency boost
> upon input events:
> 
> http://www.spinics.net/lists/cpufreq/msg00667.html
> 
> and the related changes in git://codeaurora.org/kernel/msm.git tree.
> Those patches modify the ondemand cpufreq governor. This patch series
> adds minimum and maximum CPU frequency as PM QoS parameters and
> modifies the cpufreq core to enforce the PM QoS limits. There is also
> an example module for boosting the frequency upon input events.
> 
> I've been testing these changes against Ubuntu 3.2 kernel on a Dell
> E6420 with the ACPI cpufreq driver. The patches are against
> linux-next/master, compile tested against it.
I'll test it this weekend as well.

FWIW if this works the way I hope it does then, its a feature we need
for different reasons than interactivity.  So thanks for working on
this!

> 
> V2:
> * split min and max to separate commits
> * handle PM QoS min above max as max
> * handle PM QoS max below min as min

A qos to constrain how slow the cpu goes is ok.
A qos to constrain how fast it is allowed to go is not a PM_QOS thing.

I'll review the patchset later today.


Thanks!
--mark

> 
> 	--Antti
> 
> Alex Frid (1):
>   PM QoS: Simplify PM QoS expansion/merge
> 
> Antti P Miettinen (7):
>   PM QoS: Add CPU frequency minimum as PM QoS param
>   cpufreq: Export user_policy min/max
>   cpufreq: Preserve sysfs min/max request
>   cpufreq: Enforce PM QoS minimum limit
>   input: CPU frequency booster
>   PM QoS: Add CPU frequency maximum as PM QoS param
>   cpufreq: Enforce PM QoS maximum frequency
> 
>  drivers/cpufreq/cpufreq.c     |   59 +++++++++++++-
>  drivers/input/Kconfig         |    9 ++
>  drivers/input/Makefile        |    1 +
>  drivers/input/input-cfboost.c |  174 +++++++++++++++++++++++++++++++++++++++++
>  include/linux/pm_qos.h        |   19 ++++-
>  kernel/power/qos.c            |   55 ++++++++++----
>  6 files changed, 295 insertions(+), 22 deletions(-)
>  create mode 100644 drivers/input/input-cfboost.c
> 
> -- 
> 1.7.4.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@vger.kernel.org
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Re: [PATCH v2 0/8] RFC: CPU frequency min/max as PM QoS params

[Antti P Miettinen]

mark gross <markgross@thegnar.org> writes:
> just a quick note: ever since I lost my mgross@linux.intel.com email
> I've started using markgross@thegnar.org

Sorry - I picked the @linux.intel.com address from git blame. Hmm.. is
the mark.gross@intelc.om in MAINTAINERS still valid?

> FWIW if this works the way I hope it does then, its a feature we need
> for different reasons than interactivity.  So thanks for working on
> this!

Thanks - I appreciate the feedback!

>> V2:
>> * split min and max to separate commits
>> * handle PM QoS min above max as max
>> * handle PM QoS max below min as min
>
> A qos to constrain how slow the cpu goes is ok.
> A qos to constrain how fast it is allowed to go is not a PM_QOS thing.

Thanks - I appreciate the feedback :-)

As I said earlier, I think the maximum frequency can act as a level of
energy efficiency request. If a workload knows that a certain level of
performance is adequate, the maximum frequency request can prevent
e.g. ondemand unnecessarily raising the frequency.

	--Antti

Re: [PATCH v2 1/8] PM QoS: Simplify PM QoS expansion/merge

[mark gross]

looks ok.
Signed-off-by: markgross <markgross@thegnar.org>

--mark

On Fri, Jan 13, 2012 at 02:59:12PM +0200, Antti P Miettinen wrote:
> From: Alex Frid <afrid@nvidia.com>
> 
> - Replace class ID #define with enumeration
> - Loop through PM QoS objects during initialization (rather than
>   initializing them one-by-one)
> 
> Signed-off-by: Alex Frid <afrid@nvidia.com>
> Reviewed-by: Antti Miettinen <amiettinen@nvidia.com>
> Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com>
> Reviewed-by: Scott Williams <scwilliams@nvidia.com>
> Reviewed-by: Yu-Huan Hsu <yhsu@nvidia.com>
> ---
>  include/linux/pm_qos.h |   14 +++++++++-----
>  kernel/power/qos.c     |   23 ++++++++++-------------
>  2 files changed, 19 insertions(+), 18 deletions(-)
> 
> diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
> index e5bbcba..5ac91d8 100644
> --- a/include/linux/pm_qos.h
> +++ b/include/linux/pm_qos.h
> @@ -9,12 +9,16 @@
>  #include <linux/miscdevice.h>
>  #include <linux/device.h>
>  
> -#define PM_QOS_RESERVED 0
> -#define PM_QOS_CPU_DMA_LATENCY 1
> -#define PM_QOS_NETWORK_LATENCY 2
> -#define PM_QOS_NETWORK_THROUGHPUT 3
> +enum {
> +	PM_QOS_RESERVED = 0,
> +	PM_QOS_CPU_DMA_LATENCY,
> +	PM_QOS_NETWORK_LATENCY,
> +	PM_QOS_NETWORK_THROUGHPUT,
> +
> +	/* insert new class ID */
> +	PM_QOS_NUM_CLASSES,
> +};
>  
> -#define PM_QOS_NUM_CLASSES 4
>  #define PM_QOS_DEFAULT_VALUE -1
>  
>  #define PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE	(2000 * USEC_PER_SEC)
> diff --git a/kernel/power/qos.c b/kernel/power/qos.c
> index 995e3bd..d6d6dbd 100644
> --- a/kernel/power/qos.c
> +++ b/kernel/power/qos.c
> @@ -469,21 +469,18 @@ static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
>  static int __init pm_qos_power_init(void)
>  {
>  	int ret = 0;
> +	int i;
>  
> -	ret = register_pm_qos_misc(&cpu_dma_pm_qos);
> -	if (ret < 0) {
> -		printk(KERN_ERR "pm_qos_param: cpu_dma_latency setup failed\n");
> -		return ret;
> -	}
> -	ret = register_pm_qos_misc(&network_lat_pm_qos);
> -	if (ret < 0) {
> -		printk(KERN_ERR "pm_qos_param: network_latency setup failed\n");
> -		return ret;
> +	BUILD_BUG_ON(ARRAY_SIZE(pm_qos_array) != PM_QOS_NUM_CLASSES);
> +
> +	for (i = 1; i < PM_QOS_NUM_CLASSES; i++) {
> +		ret = register_pm_qos_misc(pm_qos_array[i]);
> +		if (ret < 0) {
> +			printk(KERN_ERR "pm_qos_param: %s setup failed\n",
> +			       pm_qos_array[i]->name);
> +			return ret;
> +		}
>  	}
> -	ret = register_pm_qos_misc(&network_throughput_pm_qos);
> -	if (ret < 0)
> -		printk(KERN_ERR
> -			"pm_qos_param: network_throughput setup failed\n");
>  
>  	return ret;
>  }
> -- 
> 1.7.4.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v2 2/8] PM QoS: Add CPU frequency minimum as PM QoS param

[mark gross]

For some reason git am doesn't work with this so I had to use patch by
hand.



On Fri, Jan 13, 2012 at 02:59:13PM +0200, Antti P Miettinen wrote:
> Add minimum CPU frequency as PM QoS parameter.
> 
> Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
> ---
>  include/linux/pm_qos.h |    3 +++
>  kernel/power/qos.c     |   17 ++++++++++++++++-
>  2 files changed, 19 insertions(+), 1 deletions(-)
> 
> diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
> index 5ac91d8..54a0d00 100644
> --- a/include/linux/pm_qos.h
> +++ b/include/linux/pm_qos.h
> @@ -14,8 +14,10 @@ enum {
>  	PM_QOS_CPU_DMA_LATENCY,
>  	PM_QOS_NETWORK_LATENCY,
>  	PM_QOS_NETWORK_THROUGHPUT,
> +	PM_QOS_CPU_FREQ_MIN,
>  
>  	/* insert new class ID */
> +
>  	PM_QOS_NUM_CLASSES,
>  };
>  
> @@ -25,6 +27,7 @@ enum {
>  #define PM_QOS_NETWORK_LAT_DEFAULT_VALUE	(2000 * USEC_PER_SEC)
>  #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE	0
>  #define PM_QOS_DEV_LAT_DEFAULT_VALUE		0
> +#define PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE	0
Perhaps "#define PM_QOS_CPU_FREQ_MIN_DEFAULT_KHZ	0" might be
more descriptive.

Its nice to have the code a bit self documenting and we are missing any
comments on what units the FREQ are in.  (they are in the same units
that cpufreq uses.  KHz)

Also we need to update the Documentation/power/pm_qos_interface.txt
to explain cpu_freq_min's units.

other than this (and the git am issue) this looks good to me.

--mark
>  
>  struct pm_qos_request {
>  	struct plist_node node;
> diff --git a/kernel/power/qos.c b/kernel/power/qos.c
> index d6d6dbd..07d761a 100644
> --- a/kernel/power/qos.c
> +++ b/kernel/power/qos.c
> @@ -101,11 +101,26 @@ static struct pm_qos_object network_throughput_pm_qos = {
>  };
>  
>  
> +static BLOCKING_NOTIFIER_HEAD(cpu_freq_min_notifier);
> +static struct pm_qos_constraints cpu_freq_min_constraints = {
> +	.list = PLIST_HEAD_INIT(cpu_freq_min_constraints.list),
> +	.target_value = PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE,
> +	.default_value = PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE,
> +	.type = PM_QOS_MAX,
> +	.notifiers = &cpu_freq_min_notifier,
> +};
> +static struct pm_qos_object cpu_freq_min_pm_qos = {
> +	.constraints = &cpu_freq_min_constraints,
> +	.name = "cpu_freq_min",
> +};
> +
> +
>  static struct pm_qos_object *pm_qos_array[] = {
>  	&null_pm_qos,
>  	&cpu_dma_pm_qos,
>  	&network_lat_pm_qos,
> -	&network_throughput_pm_qos
> +	&network_throughput_pm_qos,
> +	&cpu_freq_min_pm_qos,
>  };
>  
>  static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
> -- 
> 1.7.4.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@vger.kernel.org
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Re: [PATCH v2 5/8] cpufreq: Enforce PM QoS minimum limit

[mark gross]

git am doesn't work with most of your patchset for me.

Tested-by: markgross <markgross@thegnar.org>
seems to work on my i5 laptop.

Looks good to me.

--mark

On Fri, Jan 13, 2012 at 02:59:16PM +0200, Antti P Miettinen wrote:
> Observe PM QoS CPU frequency minimum in addition
> to policy settings.
> 
> Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
> ---
>  drivers/cpufreq/cpufreq.c |   41 +++++++++++++++++++++++++++++++++++++++--
>  1 files changed, 39 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 127e37a..c2c1c62 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -29,6 +29,7 @@
>  #include <linux/completion.h>
>  #include <linux/mutex.h>
>  #include <linux/syscore_ops.h>
> +#include <linux/pm_qos.h>
>  
>  #include <trace/events/power.h>
>  
> @@ -1633,9 +1634,16 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
>  				struct cpufreq_policy *policy)
>  {
>  	int ret = 0;
> +	unsigned int pmin = policy->min;
> +	unsigned int pmax = policy->max;
> +	unsigned int qmin = min(pm_qos_request(PM_QOS_CPU_FREQ_MIN),
> +				data->max);
>  
> -	pr_debug("setting new policy for CPU %u: %u - %u kHz\n", policy->cpu,
> -		policy->min, policy->max);
> +	pr_debug("setting new policy for CPU %u: %u/%u - %u kHz\n",
> +		 policy->cpu, pmin, qmin, pmax);
> +
> +	/* clamp the new policy to PM QoS limits */
> +	policy->min = max(pmin, qmin);
>  
>  	memcpy(&policy->cpuinfo, &data->cpuinfo,
>  				sizeof(struct cpufreq_cpuinfo));
> @@ -1710,6 +1718,9 @@ static int __cpufreq_set_policy(struct cpufreq_policy *data,
>  	}
>  
>  error_out:
> +	/* restore the limits that the policy requested */
> +	policy->min = pmin;
> +	policy->max = pmax;
>  	return ret;
>  }
>  
> @@ -1903,9 +1914,32 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver)
>  }
>  EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
>  
> +static int cpu_freq_notify(struct notifier_block *b,
> +			   unsigned long l, void *v);
> +
> +static struct notifier_block min_freq_notifier = {
> +	.notifier_call = cpu_freq_notify,
> +};
> +
> +static int cpu_freq_notify(struct notifier_block *b,
> +			   unsigned long l, void *v)
> +{
> +	int cpu;
> +	pr_debug("PM QoS min %lu\n", l);
> +	for_each_online_cpu(cpu) {
> +		struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
> +		if (policy) {
> +			cpufreq_update_policy(policy->cpu);
> +			cpufreq_cpu_put(policy);
> +		}
> +	}
> +	return NOTIFY_OK;
> +}
> +
>  static int __init cpufreq_core_init(void)
>  {
>  	int cpu;
> +	int rc;
>  
>  	for_each_possible_cpu(cpu) {
>  		per_cpu(cpufreq_policy_cpu, cpu) = -1;
> @@ -1915,6 +1949,9 @@ static int __init cpufreq_core_init(void)
>  	cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj);
>  	BUG_ON(!cpufreq_global_kobject);
>  	register_syscore_ops(&cpufreq_syscore_ops);
> +	rc = pm_qos_add_notifier(PM_QOS_CPU_FREQ_MIN,
> +				 &min_freq_notifier);
> +	BUG_ON(rc);
>  
>  	return 0;
>  }
> -- 
> 1.7.4.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: [PATCH v2 7/8] PM QoS: Add CPU frequency maximum as PM QoS param

[mark gross]

I don't think this belongs in cpufreq.
--mark

On Fri, Jan 13, 2012 at 02:59:18PM +0200, Antti P Miettinen wrote:
> Add maximum CPU frequency as PM QoS parameter.
> 
> Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
> ---
>  include/linux/pm_qos.h |    2 ++
>  kernel/power/qos.c     |   15 +++++++++++++++
>  2 files changed, 17 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
> index 54a0d00..7b8d08b 100644
> --- a/include/linux/pm_qos.h
> +++ b/include/linux/pm_qos.h
> @@ -15,6 +15,7 @@ enum {
>  	PM_QOS_NETWORK_LATENCY,
>  	PM_QOS_NETWORK_THROUGHPUT,
>  	PM_QOS_CPU_FREQ_MIN,
> +	PM_QOS_CPU_FREQ_MAX,
>  
>  	/* insert new class ID */
>  
> @@ -28,6 +29,7 @@ enum {
>  #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE	0
>  #define PM_QOS_DEV_LAT_DEFAULT_VALUE		0
>  #define PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE	0
> +#define PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE	LONG_MAX
>  
>  struct pm_qos_request {
>  	struct plist_node node;
> diff --git a/kernel/power/qos.c b/kernel/power/qos.c
> index 07d761a..04b744b 100644
> --- a/kernel/power/qos.c
> +++ b/kernel/power/qos.c
> @@ -115,12 +115,27 @@ static struct pm_qos_object cpu_freq_min_pm_qos = {
>  };
>  
>  
> +static BLOCKING_NOTIFIER_HEAD(cpu_freq_max_notifier);
> +static struct pm_qos_constraints cpu_freq_max_constraints = {
> +	.list = PLIST_HEAD_INIT(cpu_freq_max_constraints.list),
> +	.target_value = PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE,
> +	.default_value = PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE,
> +	.type = PM_QOS_MIN,
> +	.notifiers = &cpu_freq_max_notifier,
> +};
> +static struct pm_qos_object cpu_freq_max_pm_qos = {
> +	.constraints = &cpu_freq_max_constraints,
> +	.name = "cpu_freq_max",
> +};
> +
> +
>  static struct pm_qos_object *pm_qos_array[] = {
>  	&null_pm_qos,
>  	&cpu_dma_pm_qos,
>  	&network_lat_pm_qos,
>  	&network_throughput_pm_qos,
>  	&cpu_freq_min_pm_qos,
> +	&cpu_freq_max_pm_qos,
>  };
>  
>  static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
> -- 
> 1.7.4.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@vger.kernel.org
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[PATCH v2 7/8] PM QoS: Add CPU frequency maximum as PM QoS param

[Antti P Miettinen]

Add maximum CPU frequency as PM QoS parameter.

Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
---
 include/linux/pm_qos.h |    2 ++
 kernel/power/qos.c     |   15 +++++++++++++++
 2 files changed, 17 insertions(+), 0 deletions(-)

diff --git a/include/linux/pm_qos.h b/include/linux/pm_qos.h
index 54a0d00..7b8d08b 100644
--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -15,6 +15,7 @@ enum {
 	PM_QOS_NETWORK_LATENCY,
 	PM_QOS_NETWORK_THROUGHPUT,
 	PM_QOS_CPU_FREQ_MIN,
+	PM_QOS_CPU_FREQ_MAX,
 
 	/* insert new class ID */
 
@@ -28,6 +29,7 @@ enum {
 #define PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE	0
 #define PM_QOS_DEV_LAT_DEFAULT_VALUE		0
 #define PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE	0
+#define PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE	LONG_MAX
 
 struct pm_qos_request {
 	struct plist_node node;
diff --git a/kernel/power/qos.c b/kernel/power/qos.c
index 07d761a..04b744b 100644
--- a/kernel/power/qos.c
+++ b/kernel/power/qos.c
@@ -115,12 +115,27 @@ static struct pm_qos_object cpu_freq_min_pm_qos = {
 };
 
 
+static BLOCKING_NOTIFIER_HEAD(cpu_freq_max_notifier);
+static struct pm_qos_constraints cpu_freq_max_constraints = {
+	.list = PLIST_HEAD_INIT(cpu_freq_max_constraints.list),
+	.target_value = PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE,
+	.default_value = PM_QOS_CPU_FREQ_MAX_DEFAULT_VALUE,
+	.type = PM_QOS_MIN,
+	.notifiers = &cpu_freq_max_notifier,
+};
+static struct pm_qos_object cpu_freq_max_pm_qos = {
+	.constraints = &cpu_freq_max_constraints,
+	.name = "cpu_freq_max",
+};
+
+
 static struct pm_qos_object *pm_qos_array[] = {
 	&null_pm_qos,
 	&cpu_dma_pm_qos,
 	&network_lat_pm_qos,
 	&network_throughput_pm_qos,
 	&cpu_freq_min_pm_qos,
+	&cpu_freq_max_pm_qos,
 };
 
 static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf,
-- 
1.7.4.1