blob: 316df247e00da306a8e4c3bb4c90aa1507a85147 [file] [log] [blame]
Dave Jonesb9170832005-05-31 19:03:47 -07001/*
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>
Alexander Clouter11a80a9c762009-02-13 19:01:01 +00007 * (C) 2009 Alexander Clouter <alex@digriz.org.uk>
Dave Jonesb9170832005-05-31 19:03:47 -07008 *
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
Viresh Kumar4d5dcc42013-03-27 15:58:58 +000014#include <linux/slab.h>
Viresh Kumar4471a342012-10-26 00:47:42 +020015#include "cpufreq_governor.h"
Dave Jonesb9170832005-05-31 19:03:47 -070016
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +010017struct cs_policy_dbs_info {
18 struct policy_dbs_info policy_dbs;
19 unsigned int down_skip;
20 unsigned int requested_freq;
21};
22
23static inline struct cs_policy_dbs_info *to_dbs_info(struct policy_dbs_info *policy_dbs)
24{
25 return container_of(policy_dbs, struct cs_policy_dbs_info, policy_dbs);
26}
27
Rafael J. Wysocki47ebaac2016-02-18 18:41:36 +010028struct cs_dbs_tuners {
29 unsigned int down_threshold;
30 unsigned int freq_step;
31};
32
Stratos Karafotisc88883c2013-02-08 17:24:24 +000033/* Conservative governor macros */
Dave Jonesb9170832005-05-31 19:03:47 -070034#define DEF_FREQUENCY_UP_THRESHOLD (80)
Dave Jonesb9170832005-05-31 19:03:47 -070035#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
Stratos Karafotis98765842013-03-22 08:03:17 +000036#define DEF_FREQUENCY_STEP (5)
Alexander Clouter2c906b32006-03-22 09:54:10 +000037#define DEF_SAMPLING_DOWN_FACTOR (1)
38#define MAX_SAMPLING_DOWN_FACTOR (10)
Dave Jonesb9170832005-05-31 19:03:47 -070039
Stratos Karafotis98765842013-03-22 08:03:17 +000040static inline unsigned int get_freq_target(struct cs_dbs_tuners *cs_tuners,
41 struct cpufreq_policy *policy)
42{
43 unsigned int freq_target = (cs_tuners->freq_step * policy->max) / 100;
44
45 /* max freq cannot be less than 100. But who knows... */
46 if (unlikely(freq_target == 0))
47 freq_target = DEF_FREQUENCY_STEP;
48
49 return freq_target;
50}
51
Viresh Kumar4471a342012-10-26 00:47:42 +020052/*
53 * Every sampling_rate, we check, if current idle time is less than 20%
Stratos Karafotis7af1c052013-03-05 22:06:29 +000054 * (default), then we try to increase frequency. Every sampling_rate *
55 * sampling_down_factor, we check, if current idle time is more than 80%
56 * (default), then we try to decrease frequency
Viresh Kumar4471a342012-10-26 00:47:42 +020057 *
58 * Any frequency increase takes it to the maximum frequency. Frequency reduction
59 * happens at minimum steps of 5% (default) of maximum frequency
60 */
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010061static unsigned int cs_dbs_timer(struct cpufreq_policy *policy)
Elias Oltmannsa8d7c3b2007-10-22 09:50:13 +020062{
Rafael J. Wysockibc505472016-02-07 16:24:26 +010063 struct policy_dbs_info *policy_dbs = policy->governor_data;
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +010064 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy_dbs);
Rafael J. Wysockibc505472016-02-07 16:24:26 +010065 struct dbs_data *dbs_data = policy_dbs->dbs_data;
Viresh Kumar4d5dcc42013-03-27 15:58:58 +000066 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010067 unsigned int load = dbs_update(policy);
Alexander Clouterf407a082009-02-13 19:01:51 +000068
69 /*
Viresh Kumar4471a342012-10-26 00:47:42 +020070 * break out if we 'cannot' reduce the speed as the user might
71 * want freq_step to be zero
72 */
Viresh Kumar4d5dcc42013-03-27 15:58:58 +000073 if (cs_tuners->freq_step == 0)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010074 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +020075
76 /* Check for frequency increase */
Viresh Kumarff4b1782016-02-09 09:01:32 +053077 if (load > dbs_data->up_threshold) {
Viresh Kumar4471a342012-10-26 00:47:42 +020078 dbs_info->down_skip = 0;
79
80 /* if we are already at full speed then break out early */
81 if (dbs_info->requested_freq == policy->max)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010082 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +020083
Stratos Karafotis98765842013-03-22 08:03:17 +000084 dbs_info->requested_freq += get_freq_target(cs_tuners, policy);
Viresh Kumar4471a342012-10-26 00:47:42 +020085
Xiaoguang Chen6d7bcb12013-11-08 13:23:52 +080086 if (dbs_info->requested_freq > policy->max)
87 dbs_info->requested_freq = policy->max;
88
Viresh Kumar4471a342012-10-26 00:47:42 +020089 __cpufreq_driver_target(policy, dbs_info->requested_freq,
90 CPUFREQ_RELATION_H);
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010091 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +020092 }
93
Stratos Karafotis7af1c052013-03-05 22:06:29 +000094 /* if sampling_down_factor is active break out early */
Viresh Kumarff4b1782016-02-09 09:01:32 +053095 if (++dbs_info->down_skip < dbs_data->sampling_down_factor)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010096 goto out;
Stratos Karafotis7af1c052013-03-05 22:06:29 +000097 dbs_info->down_skip = 0;
98
Stratos Karafotis27ed3cd2013-03-05 22:06:40 +000099 /* Check for frequency decrease */
100 if (load < cs_tuners->down_threshold) {
Xiaoguang Chen3baa9762013-11-07 10:28:50 +0800101 unsigned int freq_target;
Viresh Kumar4471a342012-10-26 00:47:42 +0200102 /*
103 * if we cannot reduce the frequency anymore, break out early
104 */
105 if (policy->cur == policy->min)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +0100106 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +0200107
Xiaoguang Chen3baa9762013-11-07 10:28:50 +0800108 freq_target = get_freq_target(cs_tuners, policy);
109 if (dbs_info->requested_freq > freq_target)
110 dbs_info->requested_freq -= freq_target;
111 else
112 dbs_info->requested_freq = policy->min;
Namhyung Kimad529a92013-02-28 05:38:01 +0000113
Viresh Kumar4471a342012-10-26 00:47:42 +0200114 __cpufreq_driver_target(policy, dbs_info->requested_freq,
Namhyung Kimfed573d2013-02-28 05:38:02 +0000115 CPUFREQ_RELATION_L);
Viresh Kumar4471a342012-10-26 00:47:42 +0200116 }
Viresh Kumar4471a342012-10-26 00:47:42 +0200117
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +0100118 out:
Rafael J. Wysocki07aa4402016-02-15 02:22:13 +0100119 return dbs_data->sampling_rate;
Fabio Baltieri66df2a012012-12-27 14:55:41 +0000120}
Viresh Kumar44472662013-01-31 17:28:02 +0000121
Viresh Kumar4471a342012-10-26 00:47:42 +0200122static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100123 void *data);
Elias Oltmannsa8d7c3b2007-10-22 09:50:13 +0200124
Viresh Kumar8e0484d2015-06-03 15:57:11 +0530125static struct notifier_block cs_cpufreq_notifier_block = {
126 .notifier_call = dbs_cpufreq_notifier,
127};
128
Dave Jonesb9170832005-05-31 19:03:47 -0700129/************************** sysfs interface ************************/
Rafael J. Wysocki7bdad342016-02-07 16:05:07 +0100130static struct dbs_governor cs_dbs_gov;
Dave Jonesb9170832005-05-31 19:03:47 -0700131
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100132static ssize_t store_sampling_down_factor(struct gov_attr_set *attr_set,
133 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700134{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100135 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Dave Jonesb9170832005-05-31 19:03:47 -0700136 unsigned int input;
137 int ret;
Dave Jones9acef482009-01-18 01:39:51 -0500138 ret = sscanf(buf, "%u", &input);
Alexander Clouter8e677ce2009-02-13 19:02:34 +0000139
Alexander Clouter2c906b32006-03-22 09:54:10 +0000140 if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700141 return -EINVAL;
142
Viresh Kumarff4b1782016-02-09 09:01:32 +0530143 dbs_data->sampling_down_factor = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700144 return count;
145}
146
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100147static ssize_t store_up_threshold(struct gov_attr_set *attr_set,
148 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700149{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100150 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000151 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Dave Jonesb9170832005-05-31 19:03:47 -0700152 unsigned int input;
153 int ret;
Dave Jones9acef482009-01-18 01:39:51 -0500154 ret = sscanf(buf, "%u", &input);
Dave Jonesb9170832005-05-31 19:03:47 -0700155
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000156 if (ret != 1 || input > 100 || input <= cs_tuners->down_threshold)
Dave Jonesb9170832005-05-31 19:03:47 -0700157 return -EINVAL;
Dave Jonesb9170832005-05-31 19:03:47 -0700158
Viresh Kumarff4b1782016-02-09 09:01:32 +0530159 dbs_data->up_threshold = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700160 return count;
161}
162
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100163static ssize_t store_down_threshold(struct gov_attr_set *attr_set,
164 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700165{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100166 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000167 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Dave Jonesb9170832005-05-31 19:03:47 -0700168 unsigned int input;
169 int ret;
Dave Jones9acef482009-01-18 01:39:51 -0500170 ret = sscanf(buf, "%u", &input);
Dave Jonesb9170832005-05-31 19:03:47 -0700171
Alexander Clouter8e677ce2009-02-13 19:02:34 +0000172 /* cannot be lower than 11 otherwise freq will not fall */
173 if (ret != 1 || input < 11 || input > 100 ||
Viresh Kumarff4b1782016-02-09 09:01:32 +0530174 input >= dbs_data->up_threshold)
Dave Jonesb9170832005-05-31 19:03:47 -0700175 return -EINVAL;
Dave Jonesb9170832005-05-31 19:03:47 -0700176
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000177 cs_tuners->down_threshold = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700178 return count;
179}
180
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100181static ssize_t store_ignore_nice_load(struct gov_attr_set *attr_set,
182 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700183{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100184 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Rafael J. Wysockia33cce12016-02-18 02:26:55 +0100185 unsigned int input;
Dave Jonesb9170832005-05-31 19:03:47 -0700186 int ret;
187
Dave Jones18a72472007-10-22 16:49:09 -0400188 ret = sscanf(buf, "%u", &input);
189 if (ret != 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700190 return -EINVAL;
191
Dave Jones18a72472007-10-22 16:49:09 -0400192 if (input > 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700193 input = 1;
Dave Jones18a72472007-10-22 16:49:09 -0400194
Viresh Kumarff4b1782016-02-09 09:01:32 +0530195 if (input == dbs_data->ignore_nice_load) /* nothing to do */
Dave Jonesb9170832005-05-31 19:03:47 -0700196 return count;
Thomas Renninger326c86d2011-03-03 21:31:27 +0100197
Viresh Kumarff4b1782016-02-09 09:01:32 +0530198 dbs_data->ignore_nice_load = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700199
Alexander Clouter8e677ce2009-02-13 19:02:34 +0000200 /* we need to re-evaluate prev_cpu_idle */
Rafael J. Wysocki8c8f77f2016-02-21 00:51:27 +0100201 gov_update_cpu_data(dbs_data);
Rafael J. Wysockia33cce12016-02-18 02:26:55 +0100202
Dave Jonesb9170832005-05-31 19:03:47 -0700203 return count;
204}
205
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100206static ssize_t store_freq_step(struct gov_attr_set *attr_set, const char *buf,
207 size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700208{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100209 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000210 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Dave Jonesb9170832005-05-31 19:03:47 -0700211 unsigned int input;
212 int ret;
Dave Jones18a72472007-10-22 16:49:09 -0400213 ret = sscanf(buf, "%u", &input);
Dave Jonesb9170832005-05-31 19:03:47 -0700214
Dave Jones18a72472007-10-22 16:49:09 -0400215 if (ret != 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700216 return -EINVAL;
217
Dave Jones18a72472007-10-22 16:49:09 -0400218 if (input > 100)
Dave Jonesb9170832005-05-31 19:03:47 -0700219 input = 100;
Dave Jones18a72472007-10-22 16:49:09 -0400220
Viresh Kumar4471a342012-10-26 00:47:42 +0200221 /*
222 * no need to test here if freq_step is zero as the user might actually
223 * want this, they would be crazy though :)
224 */
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000225 cs_tuners->freq_step = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700226 return count;
227}
228
Viresh Kumarc4435632016-02-09 09:01:33 +0530229gov_show_one_common(sampling_rate);
230gov_show_one_common(sampling_down_factor);
231gov_show_one_common(up_threshold);
232gov_show_one_common(ignore_nice_load);
233gov_show_one_common(min_sampling_rate);
234gov_show_one(cs, down_threshold);
235gov_show_one(cs, freq_step);
Viresh Kumar4471a342012-10-26 00:47:42 +0200236
Viresh Kumarc4435632016-02-09 09:01:33 +0530237gov_attr_rw(sampling_rate);
238gov_attr_rw(sampling_down_factor);
239gov_attr_rw(up_threshold);
240gov_attr_rw(ignore_nice_load);
241gov_attr_ro(min_sampling_rate);
242gov_attr_rw(down_threshold);
243gov_attr_rw(freq_step);
Dave Jonesb9170832005-05-31 19:03:47 -0700244
Viresh Kumarc4435632016-02-09 09:01:33 +0530245static struct attribute *cs_attributes[] = {
246 &min_sampling_rate.attr,
247 &sampling_rate.attr,
248 &sampling_down_factor.attr,
249 &up_threshold.attr,
250 &down_threshold.attr,
251 &ignore_nice_load.attr,
252 &freq_step.attr,
Dave Jonesb9170832005-05-31 19:03:47 -0700253 NULL
254};
255
Dave Jonesb9170832005-05-31 19:03:47 -0700256/************************** sysfs end ************************/
257
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +0100258static struct policy_dbs_info *cs_alloc(void)
259{
260 struct cs_policy_dbs_info *dbs_info;
261
262 dbs_info = kzalloc(sizeof(*dbs_info), GFP_KERNEL);
263 return dbs_info ? &dbs_info->policy_dbs : NULL;
264}
265
266static void cs_free(struct policy_dbs_info *policy_dbs)
267{
268 kfree(to_dbs_info(policy_dbs));
269}
270
Viresh Kumar8e0484d2015-06-03 15:57:11 +0530271static int cs_init(struct dbs_data *dbs_data, bool notify)
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000272{
273 struct cs_dbs_tuners *tuners;
274
Viresh Kumard5b73cd2013-08-06 22:53:06 +0530275 tuners = kzalloc(sizeof(*tuners), GFP_KERNEL);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000276 if (!tuners) {
277 pr_err("%s: kzalloc failed\n", __func__);
278 return -ENOMEM;
279 }
280
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000281 tuners->down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD;
Stratos Karafotis98765842013-03-22 08:03:17 +0000282 tuners->freq_step = DEF_FREQUENCY_STEP;
Viresh Kumarff4b1782016-02-09 09:01:32 +0530283 dbs_data->up_threshold = DEF_FREQUENCY_UP_THRESHOLD;
284 dbs_data->sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR;
285 dbs_data->ignore_nice_load = 0;
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000286
287 dbs_data->tuners = tuners;
288 dbs_data->min_sampling_rate = MIN_SAMPLING_RATE_RATIO *
289 jiffies_to_usecs(10);
Viresh Kumar8e0484d2015-06-03 15:57:11 +0530290
291 if (notify)
292 cpufreq_register_notifier(&cs_cpufreq_notifier_block,
293 CPUFREQ_TRANSITION_NOTIFIER);
294
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000295 return 0;
296}
297
Viresh Kumar8e0484d2015-06-03 15:57:11 +0530298static void cs_exit(struct dbs_data *dbs_data, bool notify)
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000299{
Viresh Kumar8e0484d2015-06-03 15:57:11 +0530300 if (notify)
301 cpufreq_unregister_notifier(&cs_cpufreq_notifier_block,
302 CPUFREQ_TRANSITION_NOTIFIER);
303
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000304 kfree(dbs_data->tuners);
305}
306
Rafael J. Wysocki702c9e52016-02-18 02:21:21 +0100307static void cs_start(struct cpufreq_policy *policy)
308{
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +0100309 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy->governor_data);
Rafael J. Wysocki702c9e52016-02-18 02:21:21 +0100310
311 dbs_info->down_skip = 0;
312 dbs_info->requested_freq = policy->cur;
313}
314
Rafael J. Wysocki7bdad342016-02-07 16:05:07 +0100315static struct dbs_governor cs_dbs_gov = {
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100316 .gov = {
317 .name = "conservative",
Rafael J. Wysocki906a6e52016-02-07 16:07:51 +0100318 .governor = cpufreq_governor_dbs,
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100319 .max_transition_latency = TRANSITION_LATENCY_LIMIT,
320 .owner = THIS_MODULE,
321 },
Viresh Kumarc4435632016-02-09 09:01:33 +0530322 .kobj_type = { .default_attrs = cs_attributes },
Viresh Kumar4471a342012-10-26 00:47:42 +0200323 .gov_dbs_timer = cs_dbs_timer,
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +0100324 .alloc = cs_alloc,
325 .free = cs_free,
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000326 .init = cs_init,
327 .exit = cs_exit,
Rafael J. Wysocki702c9e52016-02-18 02:21:21 +0100328 .start = cs_start,
Viresh Kumar4471a342012-10-26 00:47:42 +0200329};
Dave Jonesb9170832005-05-31 19:03:47 -0700330
Rafael J. Wysocki7bdad342016-02-07 16:05:07 +0100331#define CPU_FREQ_GOV_CONSERVATIVE (&cs_dbs_gov.gov)
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100332
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100333static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
334 void *data)
335{
336 struct cpufreq_freqs *freq = data;
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100337 struct cpufreq_policy *policy = cpufreq_cpu_get_raw(freq->cpu);
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +0100338 struct cs_policy_dbs_info *dbs_info;
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100339
340 if (!policy)
341 return 0;
342
343 /* policy isn't governed by conservative governor */
344 if (policy->governor != CPU_FREQ_GOV_CONSERVATIVE)
345 return 0;
346
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +0100347 dbs_info = to_dbs_info(policy->governor_data);
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100348 /*
349 * we only care if our internally tracked freq moves outside the 'valid'
350 * ranges of frequency available to us otherwise we do not change it
351 */
352 if (dbs_info->requested_freq > policy->max
353 || dbs_info->requested_freq < policy->min)
354 dbs_info->requested_freq = freq->new;
355
356 return 0;
357}
358
Dave Jonesb9170832005-05-31 19:03:47 -0700359static int __init cpufreq_gov_dbs_init(void)
360{
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100361 return cpufreq_register_governor(CPU_FREQ_GOV_CONSERVATIVE);
Dave Jonesb9170832005-05-31 19:03:47 -0700362}
363
364static void __exit cpufreq_gov_dbs_exit(void)
365{
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100366 cpufreq_unregister_governor(CPU_FREQ_GOV_CONSERVATIVE);
Dave Jonesb9170832005-05-31 19:03:47 -0700367}
368
Alexander Clouter11a80a9c762009-02-13 19:01:01 +0000369MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
Dave Jones9acef482009-01-18 01:39:51 -0500370MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
Dave Jonesb9170832005-05-31 19:03:47 -0700371 "Low Latency Frequency Transition capable processors "
372 "optimised for use in a battery environment");
Dave Jones9acef482009-01-18 01:39:51 -0500373MODULE_LICENSE("GPL");
Dave Jonesb9170832005-05-31 19:03:47 -0700374
Johannes Weiner69157192008-01-17 15:21:08 -0800375#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
Rafael J. Wysockide1df262016-02-05 02:37:42 +0100376struct cpufreq_governor *cpufreq_default_governor(void)
377{
Rafael J. Wysockiaf926182016-02-05 03:16:08 +0100378 return CPU_FREQ_GOV_CONSERVATIVE;
Rafael J. Wysockide1df262016-02-05 02:37:42 +0100379}
380
Johannes Weiner69157192008-01-17 15:21:08 -0800381fs_initcall(cpufreq_gov_dbs_init);
382#else
Dave Jonesb9170832005-05-31 19:03:47 -0700383module_init(cpufreq_gov_dbs_init);
Johannes Weiner69157192008-01-17 15:21:08 -0800384#endif
Dave Jonesb9170832005-05-31 19:03:47 -0700385module_exit(cpufreq_gov_dbs_exit);