blob: 08515f7e515fee102d0fe0e87038d2aa92f2c7d3 [file] [log] [blame]
Thomas Gleixnerd2912cb2019-06-04 10:11:33 +02001// SPDX-License-Identifier: GPL-2.0-only
Dave Jonesb9170832005-05-31 19:03:47 -07002/*
3 * drivers/cpufreq/cpufreq_conservative.c
4 *
5 * Copyright (C) 2001 Russell King
6 * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
7 * Jun Nakajima <jun.nakajima@intel.com>
Alexander Clouter11a80a9c762009-02-13 19:01:01 +00008 * (C) 2009 Alexander Clouter <alex@digriz.org.uk>
Dave Jonesb9170832005-05-31 19:03:47 -07009 */
10
Viresh Kumar4d5dcc42013-03-27 15:58:58 +000011#include <linux/slab.h>
Viresh Kumar4471a342012-10-26 00:47:42 +020012#include "cpufreq_governor.h"
Dave Jonesb9170832005-05-31 19:03:47 -070013
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +010014struct cs_policy_dbs_info {
15 struct policy_dbs_info policy_dbs;
16 unsigned int down_skip;
Rafael J. Wysockiabb66272016-10-12 21:47:03 +020017 unsigned int requested_freq;
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +010018};
19
20static inline struct cs_policy_dbs_info *to_dbs_info(struct policy_dbs_info *policy_dbs)
21{
22 return container_of(policy_dbs, struct cs_policy_dbs_info, policy_dbs);
23}
24
Rafael J. Wysocki47ebaac12016-02-18 18:41:36 +010025struct cs_dbs_tuners {
26 unsigned int down_threshold;
27 unsigned int freq_step;
28};
29
Stratos Karafotisc88883c2013-02-08 17:24:24 +000030/* Conservative governor macros */
Dave Jonesb9170832005-05-31 19:03:47 -070031#define DEF_FREQUENCY_UP_THRESHOLD (80)
Dave Jonesb9170832005-05-31 19:03:47 -070032#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
Stratos Karafotis98765842013-03-22 08:03:17 +000033#define DEF_FREQUENCY_STEP (5)
Alexander Clouter2c906b32006-03-22 09:54:10 +000034#define DEF_SAMPLING_DOWN_FACTOR (1)
35#define MAX_SAMPLING_DOWN_FACTOR (10)
Dave Jonesb9170832005-05-31 19:03:47 -070036
Viresh Kumard5f905a2016-11-14 12:30:43 +053037static inline unsigned int get_freq_step(struct cs_dbs_tuners *cs_tuners,
38 struct cpufreq_policy *policy)
Stratos Karafotis98765842013-03-22 08:03:17 +000039{
Viresh Kumard5f905a2016-11-14 12:30:43 +053040 unsigned int freq_step = (cs_tuners->freq_step * policy->max) / 100;
Stratos Karafotis98765842013-03-22 08:03:17 +000041
42 /* max freq cannot be less than 100. But who knows... */
Viresh Kumard5f905a2016-11-14 12:30:43 +053043 if (unlikely(freq_step == 0))
44 freq_step = DEF_FREQUENCY_STEP;
Stratos Karafotis98765842013-03-22 08:03:17 +000045
Viresh Kumard5f905a2016-11-14 12:30:43 +053046 return freq_step;
Stratos Karafotis98765842013-03-22 08:03:17 +000047}
48
Viresh Kumar4471a342012-10-26 00:47:42 +020049/*
50 * Every sampling_rate, we check, if current idle time is less than 20%
Stratos Karafotis7af1c052013-03-05 22:06:29 +000051 * (default), then we try to increase frequency. Every sampling_rate *
52 * sampling_down_factor, we check, if current idle time is more than 80%
53 * (default), then we try to decrease frequency
Viresh Kumar4471a342012-10-26 00:47:42 +020054 *
Stratos Karafotis42d951c2016-11-16 21:27:22 +020055 * Frequency updates happen at minimum steps of 5% (default) of maximum
56 * frequency
Viresh Kumar4471a342012-10-26 00:47:42 +020057 */
Viresh Kumar26f0dbc2016-11-08 11:06:33 +053058static unsigned int cs_dbs_update(struct cpufreq_policy *policy)
Elias Oltmannsa8d7c3b2007-10-22 09:50:13 +020059{
Rafael J. Wysockibc505472016-02-07 16:24:26 +010060 struct policy_dbs_info *policy_dbs = policy->governor_data;
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +010061 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy_dbs);
Rafael J. Wysockiabb66272016-10-12 21:47:03 +020062 unsigned int requested_freq = dbs_info->requested_freq;
Rafael J. Wysockibc505472016-02-07 16:24:26 +010063 struct dbs_data *dbs_data = policy_dbs->dbs_data;
Viresh Kumar4d5dcc42013-03-27 15:58:58 +000064 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010065 unsigned int load = dbs_update(policy);
Stratos Karafotis00bfe052016-11-16 19:26:29 +020066 unsigned int freq_step;
Alexander Clouterf407a082009-02-13 19:01:51 +000067
68 /*
Viresh Kumar4471a342012-10-26 00:47:42 +020069 * break out if we 'cannot' reduce the speed as the user might
70 * want freq_step to be zero
71 */
Viresh Kumar4d5dcc42013-03-27 15:58:58 +000072 if (cs_tuners->freq_step == 0)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +010073 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +020074
Rafael J. Wysockiabb66272016-10-12 21:47:03 +020075 /*
76 * If requested_freq is out of range, it is likely that the limits
77 * changed in the meantime, so fall back to current frequency in that
78 * case.
79 */
Rafael J. Wysockida5e79b2018-10-15 23:21:05 +020080 if (requested_freq > policy->max || requested_freq < policy->min) {
Rafael J. Wysockiabb66272016-10-12 21:47:03 +020081 requested_freq = policy->cur;
Rafael J. Wysockida5e79b2018-10-15 23:21:05 +020082 dbs_info->requested_freq = requested_freq;
83 }
Rafael J. Wysockiabb66272016-10-12 21:47:03 +020084
Stratos Karafotis00bfe052016-11-16 19:26:29 +020085 freq_step = get_freq_step(cs_tuners, policy);
86
87 /*
88 * Decrease requested_freq one freq_step for each idle period that
89 * we didn't update the frequency.
90 */
91 if (policy_dbs->idle_periods < UINT_MAX) {
92 unsigned int freq_steps = policy_dbs->idle_periods * freq_step;
93
Rafael J. Wysockida5e79b2018-10-15 23:21:05 +020094 if (requested_freq > policy->min + freq_steps)
Stratos Karafotis00bfe052016-11-16 19:26:29 +020095 requested_freq -= freq_steps;
96 else
97 requested_freq = policy->min;
98
99 policy_dbs->idle_periods = UINT_MAX;
100 }
101
Viresh Kumar4471a342012-10-26 00:47:42 +0200102 /* Check for frequency increase */
Viresh Kumarff4b1782016-02-09 09:01:32 +0530103 if (load > dbs_data->up_threshold) {
Viresh Kumar4471a342012-10-26 00:47:42 +0200104 dbs_info->down_skip = 0;
105
106 /* if we are already at full speed then break out early */
Rafael J. Wysockid352cf42016-06-13 23:33:49 +0200107 if (requested_freq == policy->max)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +0100108 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +0200109
Stratos Karafotis00bfe052016-11-16 19:26:29 +0200110 requested_freq += freq_step;
Rafael J. Wysockiabb66272016-10-12 21:47:03 +0200111 if (requested_freq > policy->max)
112 requested_freq = policy->max;
Viresh Kumar4471a342012-10-26 00:47:42 +0200113
Vincent Donnefortb894d202021-09-08 15:05:29 +0100114 __cpufreq_driver_target(policy, requested_freq,
115 CPUFREQ_RELATION_HE);
Rafael J. Wysockiabb66272016-10-12 21:47:03 +0200116 dbs_info->requested_freq = requested_freq;
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +0100117 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +0200118 }
119
Stratos Karafotis7af1c052013-03-05 22:06:29 +0000120 /* if sampling_down_factor is active break out early */
Viresh Kumarff4b1782016-02-09 09:01:32 +0530121 if (++dbs_info->down_skip < dbs_data->sampling_down_factor)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +0100122 goto out;
Stratos Karafotis7af1c052013-03-05 22:06:29 +0000123 dbs_info->down_skip = 0;
124
Stratos Karafotis27ed3cd2013-03-05 22:06:40 +0000125 /* Check for frequency decrease */
126 if (load < cs_tuners->down_threshold) {
Viresh Kumar4471a342012-10-26 00:47:42 +0200127 /*
128 * if we cannot reduce the frequency anymore, break out early
129 */
Rafael J. Wysockid352cf42016-06-13 23:33:49 +0200130 if (requested_freq == policy->min)
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +0100131 goto out;
Viresh Kumar4471a342012-10-26 00:47:42 +0200132
Viresh Kumard5f905a2016-11-14 12:30:43 +0530133 if (requested_freq > freq_step)
134 requested_freq -= freq_step;
Xiaoguang Chen3baa9762013-11-07 10:28:50 +0800135 else
Rafael J. Wysockid352cf42016-06-13 23:33:49 +0200136 requested_freq = policy->min;
Namhyung Kimad529a92013-02-28 05:38:01 +0000137
Vincent Donnefortb894d202021-09-08 15:05:29 +0100138 __cpufreq_driver_target(policy, requested_freq,
139 CPUFREQ_RELATION_LE);
Rafael J. Wysockiabb66272016-10-12 21:47:03 +0200140 dbs_info->requested_freq = requested_freq;
Viresh Kumar4471a342012-10-26 00:47:42 +0200141 }
Viresh Kumar4471a342012-10-26 00:47:42 +0200142
Rafael J. Wysocki4cccf752016-02-15 02:19:31 +0100143 out:
Rafael J. Wysocki07aa4402016-02-15 02:22:13 +0100144 return dbs_data->sampling_rate;
Fabio Baltieri66df2a012012-12-27 14:55:41 +0000145}
Viresh Kumar44472662013-01-31 17:28:02 +0000146
Dave Jonesb9170832005-05-31 19:03:47 -0700147/************************** sysfs interface ************************/
Dave Jonesb9170832005-05-31 19:03:47 -0700148
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100149static ssize_t store_sampling_down_factor(struct gov_attr_set *attr_set,
150 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700151{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100152 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Dave Jonesb9170832005-05-31 19:03:47 -0700153 unsigned int input;
154 int ret;
Dave Jones9acef482009-01-18 01:39:51 -0500155 ret = sscanf(buf, "%u", &input);
Alexander Clouter8e677ce2009-02-13 19:02:34 +0000156
Alexander Clouter2c906b32006-03-22 09:54:10 +0000157 if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700158 return -EINVAL;
159
Viresh Kumarff4b1782016-02-09 09:01:32 +0530160 dbs_data->sampling_down_factor = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700161 return count;
162}
163
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100164static ssize_t store_up_threshold(struct gov_attr_set *attr_set,
165 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700166{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100167 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000168 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Dave Jonesb9170832005-05-31 19:03:47 -0700169 unsigned int input;
170 int ret;
Dave Jones9acef482009-01-18 01:39:51 -0500171 ret = sscanf(buf, "%u", &input);
Dave Jonesb9170832005-05-31 19:03:47 -0700172
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000173 if (ret != 1 || input > 100 || input <= cs_tuners->down_threshold)
Dave Jonesb9170832005-05-31 19:03:47 -0700174 return -EINVAL;
Dave Jonesb9170832005-05-31 19:03:47 -0700175
Viresh Kumarff4b1782016-02-09 09:01:32 +0530176 dbs_data->up_threshold = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700177 return count;
178}
179
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100180static ssize_t store_down_threshold(struct gov_attr_set *attr_set,
181 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700182{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100183 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000184 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Dave Jonesb9170832005-05-31 19:03:47 -0700185 unsigned int input;
186 int ret;
Dave Jones9acef482009-01-18 01:39:51 -0500187 ret = sscanf(buf, "%u", &input);
Dave Jonesb9170832005-05-31 19:03:47 -0700188
Tomasz Wilczyńskib8e11f72017-06-11 17:28:39 +0900189 /* cannot be lower than 1 otherwise freq will not fall */
190 if (ret != 1 || input < 1 || input > 100 ||
Viresh Kumarff4b1782016-02-09 09:01:32 +0530191 input >= dbs_data->up_threshold)
Dave Jonesb9170832005-05-31 19:03:47 -0700192 return -EINVAL;
Dave Jonesb9170832005-05-31 19:03:47 -0700193
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000194 cs_tuners->down_threshold = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700195 return count;
196}
197
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100198static ssize_t store_ignore_nice_load(struct gov_attr_set *attr_set,
199 const char *buf, size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700200{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100201 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Rafael J. Wysockia33cce12016-02-18 02:26:55 +0100202 unsigned int input;
Dave Jonesb9170832005-05-31 19:03:47 -0700203 int ret;
204
Dave Jones18a72472007-10-22 16:49:09 -0400205 ret = sscanf(buf, "%u", &input);
206 if (ret != 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700207 return -EINVAL;
208
Dave Jones18a72472007-10-22 16:49:09 -0400209 if (input > 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700210 input = 1;
Dave Jones18a72472007-10-22 16:49:09 -0400211
Viresh Kumarff4b1782016-02-09 09:01:32 +0530212 if (input == dbs_data->ignore_nice_load) /* nothing to do */
Dave Jonesb9170832005-05-31 19:03:47 -0700213 return count;
Thomas Renninger326c86d2011-03-03 21:31:27 +0100214
Viresh Kumarff4b1782016-02-09 09:01:32 +0530215 dbs_data->ignore_nice_load = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700216
Alexander Clouter8e677ce2009-02-13 19:02:34 +0000217 /* we need to re-evaluate prev_cpu_idle */
Rafael J. Wysocki8c8f77f2016-02-21 00:51:27 +0100218 gov_update_cpu_data(dbs_data);
Rafael J. Wysockia33cce12016-02-18 02:26:55 +0100219
Dave Jonesb9170832005-05-31 19:03:47 -0700220 return count;
221}
222
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100223static ssize_t store_freq_step(struct gov_attr_set *attr_set, const char *buf,
224 size_t count)
Dave Jonesb9170832005-05-31 19:03:47 -0700225{
Rafael J. Wysocki0dd3c1d2016-03-22 02:47:51 +0100226 struct dbs_data *dbs_data = to_dbs_data(attr_set);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000227 struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
Dave Jonesb9170832005-05-31 19:03:47 -0700228 unsigned int input;
229 int ret;
Dave Jones18a72472007-10-22 16:49:09 -0400230 ret = sscanf(buf, "%u", &input);
Dave Jonesb9170832005-05-31 19:03:47 -0700231
Dave Jones18a72472007-10-22 16:49:09 -0400232 if (ret != 1)
Dave Jonesb9170832005-05-31 19:03:47 -0700233 return -EINVAL;
234
Dave Jones18a72472007-10-22 16:49:09 -0400235 if (input > 100)
Dave Jonesb9170832005-05-31 19:03:47 -0700236 input = 100;
Dave Jones18a72472007-10-22 16:49:09 -0400237
Viresh Kumar4471a342012-10-26 00:47:42 +0200238 /*
239 * no need to test here if freq_step is zero as the user might actually
240 * want this, they would be crazy though :)
241 */
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000242 cs_tuners->freq_step = input;
Dave Jonesb9170832005-05-31 19:03:47 -0700243 return count;
244}
245
Viresh Kumarc4435632016-02-09 09:01:33 +0530246gov_show_one_common(sampling_rate);
247gov_show_one_common(sampling_down_factor);
248gov_show_one_common(up_threshold);
249gov_show_one_common(ignore_nice_load);
Viresh Kumarc4435632016-02-09 09:01:33 +0530250gov_show_one(cs, down_threshold);
251gov_show_one(cs, freq_step);
Viresh Kumar4471a342012-10-26 00:47:42 +0200252
Viresh Kumarc4435632016-02-09 09:01:33 +0530253gov_attr_rw(sampling_rate);
254gov_attr_rw(sampling_down_factor);
255gov_attr_rw(up_threshold);
256gov_attr_rw(ignore_nice_load);
Viresh Kumarc4435632016-02-09 09:01:33 +0530257gov_attr_rw(down_threshold);
258gov_attr_rw(freq_step);
Dave Jonesb9170832005-05-31 19:03:47 -0700259
Greg Kroah-Hartmanfe262d52021-12-28 14:19:12 +0100260static struct attribute *cs_attrs[] = {
Viresh Kumarc4435632016-02-09 09:01:33 +0530261 &sampling_rate.attr,
262 &sampling_down_factor.attr,
263 &up_threshold.attr,
264 &down_threshold.attr,
265 &ignore_nice_load.attr,
266 &freq_step.attr,
Dave Jonesb9170832005-05-31 19:03:47 -0700267 NULL
268};
Greg Kroah-Hartmanfe262d52021-12-28 14:19:12 +0100269ATTRIBUTE_GROUPS(cs);
Dave Jonesb9170832005-05-31 19:03:47 -0700270
Dave Jonesb9170832005-05-31 19:03:47 -0700271/************************** sysfs end ************************/
272
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +0100273static struct policy_dbs_info *cs_alloc(void)
274{
275 struct cs_policy_dbs_info *dbs_info;
276
277 dbs_info = kzalloc(sizeof(*dbs_info), GFP_KERNEL);
278 return dbs_info ? &dbs_info->policy_dbs : NULL;
279}
280
281static void cs_free(struct policy_dbs_info *policy_dbs)
282{
283 kfree(to_dbs_info(policy_dbs));
284}
285
Rafael J. Wysocki9a15fb22016-05-18 22:59:49 +0200286static int cs_init(struct dbs_data *dbs_data)
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000287{
288 struct cs_dbs_tuners *tuners;
289
Viresh Kumard5b73cd2013-08-06 22:53:06 +0530290 tuners = kzalloc(sizeof(*tuners), GFP_KERNEL);
Viresh Kumara69d6b22016-05-18 17:55:26 +0530291 if (!tuners)
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000292 return -ENOMEM;
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000293
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000294 tuners->down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD;
Stratos Karafotis98765842013-03-22 08:03:17 +0000295 tuners->freq_step = DEF_FREQUENCY_STEP;
Viresh Kumarff4b1782016-02-09 09:01:32 +0530296 dbs_data->up_threshold = DEF_FREQUENCY_UP_THRESHOLD;
297 dbs_data->sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR;
298 dbs_data->ignore_nice_load = 0;
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000299 dbs_data->tuners = tuners;
Viresh Kumar8e0484d2015-06-03 15:57:11 +0530300
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000301 return 0;
302}
303
Rafael J. Wysocki9a15fb22016-05-18 22:59:49 +0200304static void cs_exit(struct dbs_data *dbs_data)
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000305{
306 kfree(dbs_data->tuners);
307}
308
Rafael J. Wysocki702c9e52016-02-18 02:21:21 +0100309static void cs_start(struct cpufreq_policy *policy)
310{
Rafael J. Wysocki7d5a9952016-02-18 18:40:14 +0100311 struct cs_policy_dbs_info *dbs_info = to_dbs_info(policy->governor_data);
Rafael J. Wysocki702c9e52016-02-18 02:21:21 +0100312
313 dbs_info->down_skip = 0;
Rafael J. Wysockiabb66272016-10-12 21:47:03 +0200314 dbs_info->requested_freq = policy->cur;
Rafael J. Wysocki702c9e52016-02-18 02:21:21 +0100315}
316
Rafael J. Wysockid352cf42016-06-13 23:33:49 +0200317static struct dbs_governor cs_governor = {
318 .gov = CPUFREQ_DBS_GOVERNOR_INITIALIZER("conservative"),
Greg Kroah-Hartmanfe262d52021-12-28 14:19:12 +0100319 .kobj_type = { .default_groups = cs_groups },
Viresh Kumar26f0dbc2016-11-08 11:06:33 +0530320 .gov_dbs_update = cs_dbs_update,
Rafael J. Wysockid352cf42016-06-13 23:33:49 +0200321 .alloc = cs_alloc,
322 .free = cs_free,
323 .init = cs_init,
324 .exit = cs_exit,
325 .start = cs_start,
Viresh Kumar4471a342012-10-26 00:47:42 +0200326};
Dave Jonesb9170832005-05-31 19:03:47 -0700327
Quentin Perret10dd8572020-06-29 13:54:59 +0530328#define CPU_FREQ_GOV_CONSERVATIVE (cs_governor.gov)
Dave Jonesb9170832005-05-31 19:03:47 -0700329
Alexander Clouter11a80a9c762009-02-13 19:01:01 +0000330MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
Dave Jones9acef482009-01-18 01:39:51 -0500331MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
Dave Jonesb9170832005-05-31 19:03:47 -0700332 "Low Latency Frequency Transition capable processors "
333 "optimised for use in a battery environment");
Dave Jones9acef482009-01-18 01:39:51 -0500334MODULE_LICENSE("GPL");
Dave Jonesb9170832005-05-31 19:03:47 -0700335
Johannes Weiner69157192008-01-17 15:21:08 -0800336#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
Rafael J. Wysockide1df262016-02-05 02:37:42 +0100337struct cpufreq_governor *cpufreq_default_governor(void)
338{
Quentin Perret10dd8572020-06-29 13:54:59 +0530339 return &CPU_FREQ_GOV_CONSERVATIVE;
Rafael J. Wysockide1df262016-02-05 02:37:42 +0100340}
Johannes Weiner69157192008-01-17 15:21:08 -0800341#endif
Quentin Perret10dd8572020-06-29 13:54:59 +0530342
343cpufreq_governor_init(CPU_FREQ_GOV_CONSERVATIVE);
344cpufreq_governor_exit(CPU_FREQ_GOV_CONSERVATIVE);