[mirror_ubuntu-zesty-kernel.git] / drivers / cpufreq / cpufreq_conservative.c

/*
 *  drivers/cpufreq/cpufreq_conservative.c
 *
 *  Copyright (C)  2001 Russell King
 *            (C)  2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
 *                      Jun Nakajima <jun.nakajima@intel.com>
 *            (C)  2009 Alexander Clouter <alex@digriz.org.uk>
 *
 * 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.
 */

#include <linux/cpufreq.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/percpu-defs.h>
#include <linux/sysfs.h>
#include <linux/types.h>

#include "cpufreq_governor.h"

/* Conservative governor macors */
#define DEF_FREQUENCY_UP_THRESHOLD		(80)
#define DEF_FREQUENCY_DOWN_THRESHOLD		(20)
#define DEF_SAMPLING_DOWN_FACTOR		(1)
#define MAX_SAMPLING_DOWN_FACTOR		(10)

static struct dbs_data cs_dbs_data;
static DEFINE_PER_CPU(struct cs_cpu_dbs_info_s, cs_cpu_dbs_info);

static struct cs_dbs_tuners cs_tuners = {
	.up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
	.down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
	.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
	.ignore_nice = 0,
	.freq_step = 5,
};

/*
 * Every sampling_rate, we check, if current idle time is less than 20%
 * (default), then we try to increase frequency Every sampling_rate *
 * sampling_down_factor, we check, if current idle time is more than 80%, then
 * we try to decrease frequency
 *
 * Any frequency increase takes it to the maximum frequency. Frequency reduction
 * happens at minimum steps of 5% (default) of maximum frequency
 */
static void cs_check_cpu(int cpu, unsigned int load)
{
	struct cs_cpu_dbs_info_s *dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
	struct cpufreq_policy *policy = dbs_info->cdbs.cur_policy;
	unsigned int freq_target;

	/*
	 * break out if we 'cannot' reduce the speed as the user might
	 * want freq_step to be zero
	 */
	if (cs_tuners.freq_step == 0)
		return;

	/* Check for frequency increase */
	if (load > cs_tuners.up_threshold) {
		dbs_info->down_skip = 0;

		/* if we are already at full speed then break out early */
		if (dbs_info->requested_freq == policy->max)
			return;

		freq_target = (cs_tuners.freq_step * policy->max) / 100;

		/* max freq cannot be less than 100. But who knows.... */
		if (unlikely(freq_target == 0))
			freq_target = 5;

		dbs_info->requested_freq += freq_target;
		if (dbs_info->requested_freq > policy->max)
			dbs_info->requested_freq = policy->max;

		__cpufreq_driver_target(policy, dbs_info->requested_freq,
			CPUFREQ_RELATION_H);
		return;
	}

	/*
	 * The optimal frequency is the frequency that is the lowest that can
	 * support the current CPU usage without triggering the up policy. To be
	 * safe, we focus 10 points under the threshold.
	 */
	if (load < (cs_tuners.down_threshold - 10)) {
		freq_target = (cs_tuners.freq_step * policy->max) / 100;

		dbs_info->requested_freq -= freq_target;
		if (dbs_info->requested_freq < policy->min)
			dbs_info->requested_freq = policy->min;

		/*
		 * if we cannot reduce the frequency anymore, break out early
		 */
		if (policy->cur == policy->min)
			return;

		__cpufreq_driver_target(policy, dbs_info->requested_freq,
				CPUFREQ_RELATION_H);
		return;
	}
}

static void cs_dbs_timer(struct work_struct *work)
{
	struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
			struct cs_cpu_dbs_info_s, cdbs.work.work);
	unsigned int cpu = dbs_info->cdbs.cpu;
	int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);

	mutex_lock(&dbs_info->cdbs.timer_mutex);

	dbs_check_cpu(&cs_dbs_data, cpu);

	schedule_delayed_work_on(smp_processor_id(), &dbs_info->cdbs.work,
			delay);
	mutex_unlock(&dbs_info->cdbs.timer_mutex);
}

static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
		void *data)
{
	struct cpufreq_freqs *freq = data;
	struct cs_cpu_dbs_info_s *dbs_info =
					&per_cpu(cs_cpu_dbs_info, freq->cpu);
	struct cpufreq_policy *policy;

	if (!dbs_info->enable)
		return 0;

	policy = dbs_info->cdbs.cur_policy;

	/*
	 * we only care if our internally tracked freq moves outside the 'valid'
	 * ranges of freqency available to us otherwise we do not change it
	*/
	if (dbs_info->requested_freq > policy->max
			|| dbs_info->requested_freq < policy->min)
		dbs_info->requested_freq = freq->new;

	return 0;
}

/************************** sysfs interface ************************/
static ssize_t show_sampling_rate_min(struct kobject *kobj,
				      struct attribute *attr, char *buf)
{
	return sprintf(buf, "%u\n", cs_dbs_data.min_sampling_rate);
}

static ssize_t store_sampling_down_factor(struct kobject *a,
					  struct attribute *b,
					  const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
		return -EINVAL;

	cs_tuners.sampling_down_factor = input;
	return count;
}

static ssize_t store_sampling_rate(struct kobject *a, struct attribute *b,
				   const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1)
		return -EINVAL;

	cs_tuners.sampling_rate = max(input, cs_dbs_data.min_sampling_rate);
	return count;
}

static ssize_t store_up_threshold(struct kobject *a, struct attribute *b,
				  const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1 || input > 100 || input <= cs_tuners.down_threshold)
		return -EINVAL;

	cs_tuners.up_threshold = input;
	return count;
}

static ssize_t store_down_threshold(struct kobject *a, struct attribute *b,
				    const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	/* cannot be lower than 11 otherwise freq will not fall */
	if (ret != 1 || input < 11 || input > 100 ||
			input >= cs_tuners.up_threshold)
		return -EINVAL;

	cs_tuners.down_threshold = input;
	return count;
}

static ssize_t store_ignore_nice_load(struct kobject *a, struct attribute *b,
				      const char *buf, size_t count)
{
	unsigned int input, j;
	int ret;

	ret = sscanf(buf, "%u", &input);
	if (ret != 1)
		return -EINVAL;

	if (input > 1)
		input = 1;

	if (input == cs_tuners.ignore_nice) /* nothing to do */
		return count;

	cs_tuners.ignore_nice = input;

	/* we need to re-evaluate prev_cpu_idle */
	for_each_online_cpu(j) {
		struct cs_cpu_dbs_info_s *dbs_info;
		dbs_info = &per_cpu(cs_cpu_dbs_info, j);
		dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j,
						&dbs_info->cdbs.prev_cpu_wall);
		if (cs_tuners.ignore_nice)
			dbs_info->cdbs.prev_cpu_nice =
				kcpustat_cpu(j).cpustat[CPUTIME_NICE];
	}
	return count;
}

static ssize_t store_freq_step(struct kobject *a, struct attribute *b,
			       const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1)
		return -EINVAL;

	if (input > 100)
		input = 100;

	/*
	 * no need to test here if freq_step is zero as the user might actually
	 * want this, they would be crazy though :)
	 */
	cs_tuners.freq_step = input;
	return count;
}

show_one(cs, sampling_rate, sampling_rate);
show_one(cs, sampling_down_factor, sampling_down_factor);
show_one(cs, up_threshold, up_threshold);
show_one(cs, down_threshold, down_threshold);
show_one(cs, ignore_nice_load, ignore_nice);
show_one(cs, freq_step, freq_step);

define_one_global_rw(sampling_rate);
define_one_global_rw(sampling_down_factor);
define_one_global_rw(up_threshold);
define_one_global_rw(down_threshold);
define_one_global_rw(ignore_nice_load);
define_one_global_rw(freq_step);
define_one_global_ro(sampling_rate_min);

static struct attribute *dbs_attributes[] = {
	&sampling_rate_min.attr,
	&sampling_rate.attr,
	&sampling_down_factor.attr,
	&up_threshold.attr,
	&down_threshold.attr,
	&ignore_nice_load.attr,
	&freq_step.attr,
	NULL
};

static struct attribute_group cs_attr_group = {
	.attrs = dbs_attributes,
	.name = "conservative",
};

/************************** sysfs end ************************/

define_get_cpu_dbs_routines(cs_cpu_dbs_info);

static struct notifier_block cs_cpufreq_notifier_block = {
	.notifier_call = dbs_cpufreq_notifier,
};

static struct cs_ops cs_ops = {
	.notifier_block = &cs_cpufreq_notifier_block,
};

static struct dbs_data cs_dbs_data = {
	.governor = GOV_CONSERVATIVE,
	.attr_group = &cs_attr_group,
	.tuners = &cs_tuners,
	.get_cpu_cdbs = get_cpu_cdbs,
	.get_cpu_dbs_info_s = get_cpu_dbs_info_s,
	.gov_dbs_timer = cs_dbs_timer,
	.gov_check_cpu = cs_check_cpu,
	.gov_ops = &cs_ops,
};

static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
				   unsigned int event)
{
	return cpufreq_governor_dbs(&cs_dbs_data, policy, event);
}

#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
static
#endif
struct cpufreq_governor cpufreq_gov_conservative = {
	.name			= "conservative",
	.governor		= cs_cpufreq_governor_dbs,
	.max_transition_latency	= TRANSITION_LATENCY_LIMIT,
	.owner			= THIS_MODULE,
};

static int __init cpufreq_gov_dbs_init(void)
{
	mutex_init(&cs_dbs_data.mutex);
	return cpufreq_register_governor(&cpufreq_gov_conservative);
}

static void __exit cpufreq_gov_dbs_exit(void)
{
	cpufreq_unregister_governor(&cpufreq_gov_conservative);
}

MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
		"Low Latency Frequency Transition capable processors "
		"optimised for use in a battery environment");
MODULE_LICENSE("GPL");

#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
fs_initcall(cpufreq_gov_dbs_init);
#else
module_init(cpufreq_gov_dbs_init);
#endif
module_exit(cpufreq_gov_dbs_exit);
Commit	Line	Data
b9170836 DJ	1	/*
	2	* drivers/cpufreq/cpufreq_conservative.c
	3	*
	4	* Copyright (C) 2001 Russell King
	5	* (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
	6	* Jun Nakajima <jun.nakajima@intel.com>
11a80a9c	7	* (C) 2009 Alexander Clouter <alex@digriz.org.uk>
b9170836 DJ	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*/
	13
b9170836	14	#include <linux/cpufreq.h>
4471a34f VK	15	#include <linux/init.h>
4471a34f VK	16	#include <linux/kernel.h>
b9170836	17	#include <linux/kernel_stat.h>
4471a34f VK	18	#include <linux/kobject.h>
4471a34f VK	19	#include <linux/module.h>
3fc54d37	20	#include <linux/mutex.h>
4471a34f VK	21	#include <linux/notifier.h>
	22	#include <linux/percpu-defs.h>
	23	#include <linux/sysfs.h>
	24	#include <linux/types.h>
8e677ce8	25
4471a34f	26	#include "cpufreq_governor.h"
b9170836	27
4471a34f	28	/* Conservative governor macors */
b9170836	29	#define DEF_FREQUENCY_UP_THRESHOLD (80)
b9170836	30	#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
2c906b31 AC	31	#define DEF_SAMPLING_DOWN_FACTOR (1)
2c906b31 AC	32	#define MAX_SAMPLING_DOWN_FACTOR (10)
b9170836	33
4471a34f VK	34	static struct dbs_data cs_dbs_data;
4471a34f VK	35	static DEFINE_PER_CPU(struct cs_cpu_dbs_info_s, cs_cpu_dbs_info);
b9170836	36
4471a34f	37	static struct cs_dbs_tuners cs_tuners = {
18a7247d DJ	38	.up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
	39	.down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
	40	.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
	41	.ignore_nice = 0,
	42	.freq_step = 5,
b9170836 DJ	43	};
b9170836 DJ	44
4471a34f VK	45	/*
	46	* Every sampling_rate, we check, if current idle time is less than 20%
	47	* (default), then we try to increase frequency Every sampling_rate *
	48	* sampling_down_factor, we check, if current idle time is more than 80%, then
	49	* we try to decrease frequency
	50	*
	51	* Any frequency increase takes it to the maximum frequency. Frequency reduction
	52	* happens at minimum steps of 5% (default) of maximum frequency
	53	*/
	54	static void cs_check_cpu(int cpu, unsigned int load)
a8d7c3bc	55	{
4471a34f VK	56	struct cs_cpu_dbs_info_s *dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
	57	struct cpufreq_policy *policy = dbs_info->cdbs.cur_policy;
	58	unsigned int freq_target;
	59
	60	/*
	61	* break out if we 'cannot' reduce the speed as the user might
	62	* want freq_step to be zero
	63	*/
	64	if (cs_tuners.freq_step == 0)
	65	return;
	66
	67	/* Check for frequency increase */
	68	if (load > cs_tuners.up_threshold) {
	69	dbs_info->down_skip = 0;
	70
	71	/* if we are already at full speed then break out early */
	72	if (dbs_info->requested_freq == policy->max)
	73	return;
	74
	75	freq_target = (cs_tuners.freq_step * policy->max) / 100;
	76
	77	/* max freq cannot be less than 100. But who knows.... */
	78	if (unlikely(freq_target == 0))
	79	freq_target = 5;
	80
	81	dbs_info->requested_freq += freq_target;
	82	if (dbs_info->requested_freq > policy->max)
	83	dbs_info->requested_freq = policy->max;
a8d7c3bc	84
4471a34f VK	85	__cpufreq_driver_target(policy, dbs_info->requested_freq,
	86	CPUFREQ_RELATION_H);
	87	return;
	88	}
	89
	90	/*
	91	* The optimal frequency is the frequency that is the lowest that can
	92	* support the current CPU usage without triggering the up policy. To be
	93	* safe, we focus 10 points under the threshold.
	94	*/
	95	if (load < (cs_tuners.down_threshold - 10)) {
	96	freq_target = (cs_tuners.freq_step * policy->max) / 100;
	97
	98	dbs_info->requested_freq -= freq_target;
	99	if (dbs_info->requested_freq < policy->min)
	100	dbs_info->requested_freq = policy->min;
	101
	102	/*
	103	* if we cannot reduce the frequency anymore, break out early
	104	*/
	105	if (policy->cur == policy->min)
	106	return;
	107
	108	__cpufreq_driver_target(policy, dbs_info->requested_freq,
	109	CPUFREQ_RELATION_H);
	110	return;
	111	}
	112	}
	113
	114	static void cs_dbs_timer(struct work_struct *work)
	115	{
	116	struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
	117	struct cs_cpu_dbs_info_s, cdbs.work.work);
	118	unsigned int cpu = dbs_info->cdbs.cpu;
	119	int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);
	120
	121	mutex_lock(&dbs_info->cdbs.timer_mutex);
	122
	123	dbs_check_cpu(&cs_dbs_data, cpu);
	124
2abfa876 RA	125	schedule_delayed_work_on(smp_processor_id(), &dbs_info->cdbs.work,
2abfa876 RA	126	delay);
4471a34f VK	127	mutex_unlock(&dbs_info->cdbs.timer_mutex);
	128	}
	129
	130	static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
	131	void *data)
	132	{
	133	struct cpufreq_freqs *freq = data;
	134	struct cs_cpu_dbs_info_s *dbs_info =
	135	&per_cpu(cs_cpu_dbs_info, freq->cpu);
f407a08b AC	136	struct cpufreq_policy *policy;
f407a08b AC	137
4471a34f	138	if (!dbs_info->enable)
a8d7c3bc EO	139	return 0;
a8d7c3bc EO	140
4471a34f	141	policy = dbs_info->cdbs.cur_policy;
f407a08b AC	142
f407a08b AC	143	/*
4471a34f VK	144	* we only care if our internally tracked freq moves outside the 'valid'
4471a34f VK	145	* ranges of freqency available to us otherwise we do not change it
f407a08b	146	*/
4471a34f VK	147	if (dbs_info->requested_freq > policy->max
	148	\|\| dbs_info->requested_freq < policy->min)
	149	dbs_info->requested_freq = freq->new;
a8d7c3bc EO	150
	151	return 0;
	152	}
	153
b9170836	154	/************************ sysfs interface **********************/
49b015ce TR	155	static ssize_t show_sampling_rate_min(struct kobject *kobj,
49b015ce TR	156	struct attribute attr, char buf)
b9170836	157	{
4471a34f	158	return sprintf(buf, "%u\n", cs_dbs_data.min_sampling_rate);
b9170836 DJ	159	}
b9170836 DJ	160
49b015ce TR	161	static ssize_t store_sampling_down_factor(struct kobject *a,
	162	struct attribute *b,
	163	const char *buf, size_t count)
b9170836 DJ	164	{
	165	unsigned int input;
	166	int ret;
9acef487	167	ret = sscanf(buf, "%u", &input);
8e677ce8	168
2c906b31	169	if (ret != 1 \|\| input > MAX_SAMPLING_DOWN_FACTOR \|\| input < 1)
b9170836 DJ	170	return -EINVAL;
b9170836 DJ	171
4471a34f	172	cs_tuners.sampling_down_factor = input;
b9170836 DJ	173	return count;
	174	}
	175
49b015ce TR	176	static ssize_t store_sampling_rate(struct kobject a, struct attribute b,
49b015ce TR	177	const char *buf, size_t count)
b9170836 DJ	178	{
	179	unsigned int input;
	180	int ret;
9acef487	181	ret = sscanf(buf, "%u", &input);
b9170836	182
8e677ce8	183	if (ret != 1)
b9170836	184	return -EINVAL;
8e677ce8	185
4471a34f	186	cs_tuners.sampling_rate = max(input, cs_dbs_data.min_sampling_rate);
b9170836 DJ	187	return count;
	188	}
	189
49b015ce TR	190	static ssize_t store_up_threshold(struct kobject a, struct attribute b,
49b015ce TR	191	const char *buf, size_t count)
b9170836 DJ	192	{
	193	unsigned int input;
	194	int ret;
9acef487	195	ret = sscanf(buf, "%u", &input);
b9170836	196
4471a34f	197	if (ret != 1 \|\| input > 100 \|\| input <= cs_tuners.down_threshold)
b9170836	198	return -EINVAL;
b9170836	199
4471a34f	200	cs_tuners.up_threshold = input;
b9170836 DJ	201	return count;
	202	}
	203
49b015ce TR	204	static ssize_t store_down_threshold(struct kobject a, struct attribute b,
49b015ce TR	205	const char *buf, size_t count)
b9170836 DJ	206	{
	207	unsigned int input;
	208	int ret;
9acef487	209	ret = sscanf(buf, "%u", &input);
b9170836	210
8e677ce8 AC	211	/* cannot be lower than 11 otherwise freq will not fall */
8e677ce8 AC	212	if (ret != 1 \|\| input < 11 \|\| input > 100 \|\|
4471a34f	213	input >= cs_tuners.up_threshold)
b9170836	214	return -EINVAL;
b9170836	215
4471a34f	216	cs_tuners.down_threshold = input;
b9170836 DJ	217	return count;
	218	}
	219
49b015ce TR	220	static ssize_t store_ignore_nice_load(struct kobject a, struct attribute b,
49b015ce TR	221	const char *buf, size_t count)
b9170836	222	{
4471a34f	223	unsigned int input, j;
b9170836 DJ	224	int ret;
b9170836 DJ	225
18a7247d DJ	226	ret = sscanf(buf, "%u", &input);
18a7247d DJ	227	if (ret != 1)
b9170836 DJ	228	return -EINVAL;
b9170836 DJ	229
18a7247d	230	if (input > 1)
b9170836	231	input = 1;
18a7247d	232
4471a34f	233	if (input == cs_tuners.ignore_nice) /* nothing to do */
b9170836	234	return count;
326c86de	235
4471a34f	236	cs_tuners.ignore_nice = input;
b9170836	237
8e677ce8	238	/* we need to re-evaluate prev_cpu_idle */
dac1c1a5	239	for_each_online_cpu(j) {
4471a34f	240	struct cs_cpu_dbs_info_s *dbs_info;
245b2e70	241	dbs_info = &per_cpu(cs_cpu_dbs_info, j);
4471a34f VK	242	dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j,
	243	&dbs_info->cdbs.prev_cpu_wall);
	244	if (cs_tuners.ignore_nice)
	245	dbs_info->cdbs.prev_cpu_nice =
	246	kcpustat_cpu(j).cpustat[CPUTIME_NICE];
b9170836	247	}
b9170836 DJ	248	return count;
	249	}
	250
49b015ce TR	251	static ssize_t store_freq_step(struct kobject a, struct attribute b,
49b015ce TR	252	const char *buf, size_t count)
b9170836 DJ	253	{
	254	unsigned int input;
	255	int ret;
18a7247d	256	ret = sscanf(buf, "%u", &input);
b9170836	257
18a7247d	258	if (ret != 1)
b9170836 DJ	259	return -EINVAL;
b9170836 DJ	260
18a7247d	261	if (input > 100)
b9170836	262	input = 100;
18a7247d	263
4471a34f VK	264	/*
	265	* no need to test here if freq_step is zero as the user might actually
	266	* want this, they would be crazy though :)
	267	*/
	268	cs_tuners.freq_step = input;
b9170836 DJ	269	return count;
	270	}
	271
4471a34f VK	272	show_one(cs, sampling_rate, sampling_rate);
	273	show_one(cs, sampling_down_factor, sampling_down_factor);
	274	show_one(cs, up_threshold, up_threshold);
	275	show_one(cs, down_threshold, down_threshold);
	276	show_one(cs, ignore_nice_load, ignore_nice);
	277	show_one(cs, freq_step, freq_step);
	278
6dad2a29 BP	279	define_one_global_rw(sampling_rate);
	280	define_one_global_rw(sampling_down_factor);
	281	define_one_global_rw(up_threshold);
	282	define_one_global_rw(down_threshold);
	283	define_one_global_rw(ignore_nice_load);
	284	define_one_global_rw(freq_step);
4471a34f	285	define_one_global_ro(sampling_rate_min);
b9170836	286
9acef487	287	static struct attribute *dbs_attributes[] = {
b9170836 DJ	288	&sampling_rate_min.attr,
	289	&sampling_rate.attr,
	290	&sampling_down_factor.attr,
	291	&up_threshold.attr,
	292	&down_threshold.attr,
001893cd	293	&ignore_nice_load.attr,
b9170836 DJ	294	&freq_step.attr,
	295	NULL
	296	};
	297
4471a34f	298	static struct attribute_group cs_attr_group = {
b9170836 DJ	299	.attrs = dbs_attributes,
	300	.name = "conservative",
	301	};
	302
	303	/************************ sysfs end **********************/
	304
4471a34f	305	define_get_cpu_dbs_routines(cs_cpu_dbs_info);
8e677ce8	306
4471a34f VK	307	static struct notifier_block cs_cpufreq_notifier_block = {
	308	.notifier_call = dbs_cpufreq_notifier,
	309	};
8e677ce8	310
4471a34f VK	311	static struct cs_ops cs_ops = {
	312	.notifier_block = &cs_cpufreq_notifier_block,
	313	};
b9170836	314
4471a34f VK	315	static struct dbs_data cs_dbs_data = {
	316	.governor = GOV_CONSERVATIVE,
	317	.attr_group = &cs_attr_group,
	318	.tuners = &cs_tuners,
	319	.get_cpu_cdbs = get_cpu_cdbs,
	320	.get_cpu_dbs_info_s = get_cpu_dbs_info_s,
	321	.gov_dbs_timer = cs_dbs_timer,
	322	.gov_check_cpu = cs_check_cpu,
	323	.gov_ops = &cs_ops,
	324	};
b9170836	325
4471a34f	326	static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
b9170836 DJ	327	unsigned int event)
b9170836 DJ	328	{
4471a34f	329	return cpufreq_governor_dbs(&cs_dbs_data, policy, event);
b9170836 DJ	330	}
b9170836 DJ	331
c4d14bc0 SW	332	#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	333	static
	334	#endif
1c256245 TR	335	struct cpufreq_governor cpufreq_gov_conservative = {
1c256245 TR	336	.name = "conservative",
4471a34f	337	.governor = cs_cpufreq_governor_dbs,
1c256245 TR	338	.max_transition_latency = TRANSITION_LATENCY_LIMIT,
1c256245 TR	339	.owner = THIS_MODULE,
b9170836 DJ	340	};
	341
	342	static int __init cpufreq_gov_dbs_init(void)
	343	{
4471a34f	344	mutex_init(&cs_dbs_data.mutex);
57df5573	345	return cpufreq_register_governor(&cpufreq_gov_conservative);
b9170836 DJ	346	}
	347
	348	static void __exit cpufreq_gov_dbs_exit(void)
	349	{
1c256245	350	cpufreq_unregister_governor(&cpufreq_gov_conservative);
b9170836 DJ	351	}
b9170836 DJ	352
11a80a9c	353	MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
9acef487	354	MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
b9170836 DJ	355	"Low Latency Frequency Transition capable processors "
b9170836 DJ	356	"optimised for use in a battery environment");
9acef487	357	MODULE_LICENSE("GPL");
b9170836	358
6915719b JW	359	#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	360	fs_initcall(cpufreq_gov_dbs_init);
	361	#else
b9170836	362	module_init(cpufreq_gov_dbs_init);
6915719b	363	#endif
b9170836	364	module_exit(cpufreq_gov_dbs_exit);