[GitHub/mt8127/android_kernel_alcatel_ttab.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_timer_update(struct cs_cpu_dbs_info_s *dbs_info, bool sample,
			    struct delayed_work *dw)
{
	unsigned int cpu = dbs_info->cdbs.cur_policy->cpu;
	int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);

	if (sample)
		dbs_check_cpu(&cs_dbs_data, cpu);

	schedule_delayed_work_on(smp_processor_id(), dw, delay);
}

static void cs_timer_coordinated(struct cs_cpu_dbs_info_s *dbs_info_local,
				 struct delayed_work *dw)
{
	struct cs_cpu_dbs_info_s *dbs_info;
	ktime_t time_now;
	s64 delta_us;
	bool sample = true;

	/* use leader CPU's dbs_info */
	dbs_info = &per_cpu(cs_cpu_dbs_info,
			    dbs_info_local->cdbs.cur_policy->cpu);
	mutex_lock(&dbs_info->cdbs.timer_mutex);

	time_now = ktime_get();
	delta_us = ktime_us_delta(time_now, dbs_info->cdbs.time_stamp);

	/* Do nothing if we recently have sampled */
	if (delta_us < (s64)(cs_tuners.sampling_rate / 2))
		sample = false;
	else
		dbs_info->cdbs.time_stamp = time_now;

	cs_timer_update(dbs_info, sample, dw);
	mutex_unlock(&dbs_info->cdbs.timer_mutex);
}

static void cs_dbs_timer(struct work_struct *work)
{
	struct delayed_work *dw = to_delayed_work(work);
	struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
			struct cs_cpu_dbs_info_s, cdbs.work.work);

	if (policy_is_shared(dbs_info->cdbs.cur_policy)) {
		cs_timer_coordinated(dbs_info, dw);
	} else {
		mutex_lock(&dbs_info->cdbs.timer_mutex);
		cs_timer_update(dbs_info, true, dw);
		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
66df2a01 FB	114	static void cs_timer_update(struct cs_cpu_dbs_info_s *dbs_info, bool sample,
66df2a01 FB	115	struct delayed_work *dw)
4471a34f	116	{
09dca5ae	117	unsigned int cpu = dbs_info->cdbs.cur_policy->cpu;
4471a34f VK	118	int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);
4471a34f VK	119
66df2a01 FB	120	if (sample)
	121	dbs_check_cpu(&cs_dbs_data, cpu);
	122
	123	schedule_delayed_work_on(smp_processor_id(), dw, delay);
	124	}
	125
	126	static void cs_timer_coordinated(struct cs_cpu_dbs_info_s *dbs_info_local,
	127	struct delayed_work *dw)
	128	{
	129	struct cs_cpu_dbs_info_s *dbs_info;
	130	ktime_t time_now;
	131	s64 delta_us;
	132	bool sample = true;
	133
	134	/* use leader CPU's dbs_info */
09dca5ae FB	135	dbs_info = &per_cpu(cs_cpu_dbs_info,
09dca5ae FB	136	dbs_info_local->cdbs.cur_policy->cpu);
4471a34f VK	137	mutex_lock(&dbs_info->cdbs.timer_mutex);
4471a34f VK	138
66df2a01 FB	139	time_now = ktime_get();
66df2a01 FB	140	delta_us = ktime_us_delta(time_now, dbs_info->cdbs.time_stamp);
4471a34f	141
66df2a01 FB	142	/* Do nothing if we recently have sampled */
	143	if (delta_us < (s64)(cs_tuners.sampling_rate / 2))
	144	sample = false;
	145	else
	146	dbs_info->cdbs.time_stamp = time_now;
	147
	148	cs_timer_update(dbs_info, sample, dw);
4471a34f VK	149	mutex_unlock(&dbs_info->cdbs.timer_mutex);
	150	}
	151
66df2a01 FB	152	static void cs_dbs_timer(struct work_struct *work)
	153	{
	154	struct delayed_work *dw = to_delayed_work(work);
	155	struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
	156	struct cs_cpu_dbs_info_s, cdbs.work.work);
	157
2624f90c	158	if (policy_is_shared(dbs_info->cdbs.cur_policy)) {
66df2a01 FB	159	cs_timer_coordinated(dbs_info, dw);
	160	} else {
	161	mutex_lock(&dbs_info->cdbs.timer_mutex);
	162	cs_timer_update(dbs_info, true, dw);
	163	mutex_unlock(&dbs_info->cdbs.timer_mutex);
	164	}
	165	}
4471a34f VK	166	static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
	167	void *data)
	168	{
	169	struct cpufreq_freqs *freq = data;
	170	struct cs_cpu_dbs_info_s *dbs_info =
	171	&per_cpu(cs_cpu_dbs_info, freq->cpu);
f407a08b AC	172	struct cpufreq_policy *policy;
f407a08b AC	173
4471a34f	174	if (!dbs_info->enable)
a8d7c3bc EO	175	return 0;
a8d7c3bc EO	176
4471a34f	177	policy = dbs_info->cdbs.cur_policy;
f407a08b AC	178
f407a08b AC	179	/*
4471a34f VK	180	* we only care if our internally tracked freq moves outside the 'valid'
4471a34f VK	181	* ranges of freqency available to us otherwise we do not change it
f407a08b	182	*/
4471a34f VK	183	if (dbs_info->requested_freq > policy->max
	184	\|\| dbs_info->requested_freq < policy->min)
	185	dbs_info->requested_freq = freq->new;
a8d7c3bc EO	186
	187	return 0;
	188	}
	189
b9170836	190	/************************ sysfs interface **********************/
49b015ce TR	191	static ssize_t show_sampling_rate_min(struct kobject *kobj,
49b015ce TR	192	struct attribute attr, char buf)
b9170836	193	{
4471a34f	194	return sprintf(buf, "%u\n", cs_dbs_data.min_sampling_rate);
b9170836 DJ	195	}
b9170836 DJ	196
49b015ce TR	197	static ssize_t store_sampling_down_factor(struct kobject *a,
	198	struct attribute *b,
	199	const char *buf, size_t count)
b9170836 DJ	200	{
	201	unsigned int input;
	202	int ret;
9acef487	203	ret = sscanf(buf, "%u", &input);
8e677ce8	204
2c906b31	205	if (ret != 1 \|\| input > MAX_SAMPLING_DOWN_FACTOR \|\| input < 1)
b9170836 DJ	206	return -EINVAL;
b9170836 DJ	207
4471a34f	208	cs_tuners.sampling_down_factor = input;
b9170836 DJ	209	return count;
	210	}
	211
49b015ce TR	212	static ssize_t store_sampling_rate(struct kobject a, struct attribute b,
49b015ce TR	213	const char *buf, size_t count)
b9170836 DJ	214	{
	215	unsigned int input;
	216	int ret;
9acef487	217	ret = sscanf(buf, "%u", &input);
b9170836	218
8e677ce8	219	if (ret != 1)
b9170836	220	return -EINVAL;
8e677ce8	221
4471a34f	222	cs_tuners.sampling_rate = max(input, cs_dbs_data.min_sampling_rate);
b9170836 DJ	223	return count;
	224	}
	225
49b015ce TR	226	static ssize_t store_up_threshold(struct kobject a, struct attribute b,
49b015ce TR	227	const char *buf, size_t count)
b9170836 DJ	228	{
	229	unsigned int input;
	230	int ret;
9acef487	231	ret = sscanf(buf, "%u", &input);
b9170836	232
4471a34f	233	if (ret != 1 \|\| input > 100 \|\| input <= cs_tuners.down_threshold)
b9170836	234	return -EINVAL;
b9170836	235
4471a34f	236	cs_tuners.up_threshold = input;
b9170836 DJ	237	return count;
	238	}
	239
49b015ce TR	240	static ssize_t store_down_threshold(struct kobject a, struct attribute b,
49b015ce TR	241	const char *buf, size_t count)
b9170836 DJ	242	{
	243	unsigned int input;
	244	int ret;
9acef487	245	ret = sscanf(buf, "%u", &input);
b9170836	246
8e677ce8 AC	247	/* cannot be lower than 11 otherwise freq will not fall */
8e677ce8 AC	248	if (ret != 1 \|\| input < 11 \|\| input > 100 \|\|
4471a34f	249	input >= cs_tuners.up_threshold)
b9170836	250	return -EINVAL;
b9170836	251
4471a34f	252	cs_tuners.down_threshold = input;
b9170836 DJ	253	return count;
	254	}
	255
49b015ce TR	256	static ssize_t store_ignore_nice_load(struct kobject a, struct attribute b,
49b015ce TR	257	const char *buf, size_t count)
b9170836	258	{
4471a34f	259	unsigned int input, j;
b9170836 DJ	260	int ret;
b9170836 DJ	261
18a7247d DJ	262	ret = sscanf(buf, "%u", &input);
18a7247d DJ	263	if (ret != 1)
b9170836 DJ	264	return -EINVAL;
b9170836 DJ	265
18a7247d	266	if (input > 1)
b9170836	267	input = 1;
18a7247d	268
4471a34f	269	if (input == cs_tuners.ignore_nice) /* nothing to do */
b9170836	270	return count;
326c86de	271
4471a34f	272	cs_tuners.ignore_nice = input;
b9170836	273
8e677ce8	274	/* we need to re-evaluate prev_cpu_idle */
dac1c1a5	275	for_each_online_cpu(j) {
4471a34f	276	struct cs_cpu_dbs_info_s *dbs_info;
245b2e70	277	dbs_info = &per_cpu(cs_cpu_dbs_info, j);
4471a34f VK	278	dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j,
	279	&dbs_info->cdbs.prev_cpu_wall);
	280	if (cs_tuners.ignore_nice)
	281	dbs_info->cdbs.prev_cpu_nice =
	282	kcpustat_cpu(j).cpustat[CPUTIME_NICE];
b9170836	283	}
b9170836 DJ	284	return count;
	285	}
	286
49b015ce TR	287	static ssize_t store_freq_step(struct kobject a, struct attribute b,
49b015ce TR	288	const char *buf, size_t count)
b9170836 DJ	289	{
	290	unsigned int input;
	291	int ret;
18a7247d	292	ret = sscanf(buf, "%u", &input);
b9170836	293
18a7247d	294	if (ret != 1)
b9170836 DJ	295	return -EINVAL;
b9170836 DJ	296
18a7247d	297	if (input > 100)
b9170836	298	input = 100;
18a7247d	299
4471a34f VK	300	/*
	301	* no need to test here if freq_step is zero as the user might actually
	302	* want this, they would be crazy though :)
	303	*/
	304	cs_tuners.freq_step = input;
b9170836 DJ	305	return count;
	306	}
	307
4471a34f VK	308	show_one(cs, sampling_rate, sampling_rate);
	309	show_one(cs, sampling_down_factor, sampling_down_factor);
	310	show_one(cs, up_threshold, up_threshold);
	311	show_one(cs, down_threshold, down_threshold);
	312	show_one(cs, ignore_nice_load, ignore_nice);
	313	show_one(cs, freq_step, freq_step);
	314
6dad2a29 BP	315	define_one_global_rw(sampling_rate);
	316	define_one_global_rw(sampling_down_factor);
	317	define_one_global_rw(up_threshold);
	318	define_one_global_rw(down_threshold);
	319	define_one_global_rw(ignore_nice_load);
	320	define_one_global_rw(freq_step);
4471a34f	321	define_one_global_ro(sampling_rate_min);
b9170836	322
9acef487	323	static struct attribute *dbs_attributes[] = {
b9170836 DJ	324	&sampling_rate_min.attr,
	325	&sampling_rate.attr,
	326	&sampling_down_factor.attr,
	327	&up_threshold.attr,
	328	&down_threshold.attr,
001893cd	329	&ignore_nice_load.attr,
b9170836 DJ	330	&freq_step.attr,
	331	NULL
	332	};
	333
4471a34f	334	static struct attribute_group cs_attr_group = {
b9170836 DJ	335	.attrs = dbs_attributes,
	336	.name = "conservative",
	337	};
	338
	339	/************************ sysfs end **********************/
	340
4471a34f	341	define_get_cpu_dbs_routines(cs_cpu_dbs_info);
8e677ce8	342
4471a34f VK	343	static struct notifier_block cs_cpufreq_notifier_block = {
	344	.notifier_call = dbs_cpufreq_notifier,
	345	};
8e677ce8	346
4471a34f VK	347	static struct cs_ops cs_ops = {
	348	.notifier_block = &cs_cpufreq_notifier_block,
	349	};
b9170836	350
4471a34f VK	351	static struct dbs_data cs_dbs_data = {
	352	.governor = GOV_CONSERVATIVE,
	353	.attr_group = &cs_attr_group,
	354	.tuners = &cs_tuners,
	355	.get_cpu_cdbs = get_cpu_cdbs,
	356	.get_cpu_dbs_info_s = get_cpu_dbs_info_s,
	357	.gov_dbs_timer = cs_dbs_timer,
	358	.gov_check_cpu = cs_check_cpu,
	359	.gov_ops = &cs_ops,
	360	};
b9170836	361
4471a34f	362	static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
b9170836 DJ	363	unsigned int event)
b9170836 DJ	364	{
4471a34f	365	return cpufreq_governor_dbs(&cs_dbs_data, policy, event);
b9170836 DJ	366	}
b9170836 DJ	367
c4d14bc0 SW	368	#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	369	static
	370	#endif
1c256245 TR	371	struct cpufreq_governor cpufreq_gov_conservative = {
1c256245 TR	372	.name = "conservative",
4471a34f	373	.governor = cs_cpufreq_governor_dbs,
1c256245 TR	374	.max_transition_latency = TRANSITION_LATENCY_LIMIT,
1c256245 TR	375	.owner = THIS_MODULE,
b9170836 DJ	376	};
	377
	378	static int __init cpufreq_gov_dbs_init(void)
	379	{
4471a34f	380	mutex_init(&cs_dbs_data.mutex);
57df5573	381	return cpufreq_register_governor(&cpufreq_gov_conservative);
b9170836 DJ	382	}
	383
	384	static void __exit cpufreq_gov_dbs_exit(void)
	385	{
1c256245	386	cpufreq_unregister_governor(&cpufreq_gov_conservative);
b9170836 DJ	387	}
b9170836 DJ	388
11a80a9c	389	MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
9acef487	390	MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
b9170836 DJ	391	"Low Latency Frequency Transition capable processors "
b9170836 DJ	392	"optimised for use in a battery environment");
9acef487	393	MODULE_LICENSE("GPL");
b9170836	394
6915719b JW	395	#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	396	fs_initcall(cpufreq_gov_dbs_init);
	397	#else
b9170836	398	module_init(cpufreq_gov_dbs_init);
6915719b	399	#endif
b9170836	400	module_exit(cpufreq_gov_dbs_exit);