blob: 5bfda2bfdf4f2665d840af18962c2f8e097be858 [file] [log] [blame]
Thomas Gleixnerd2912cb2019-06-04 10:11:33 +02001// SPDX-License-Identifier: GPL-2.0-only
Linus Torvalds1da177e2005-04-16 15:20:36 -07002/*
3 * linux/drivers/cpufreq/cpufreq.c
4 *
5 * Copyright (C) 2001 Russell King
6 * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
Viresh Kumarbb176f72013-06-19 14:19:33 +05307 * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 *
Ashok Rajc32b6b82005-10-30 14:59:54 -08009 * Oct 2005 - Ashok Raj <ashok.raj@intel.com>
Dave Jones32ee8c32006-02-28 00:43:23 -050010 * Added handling for CPU hotplug
Dave Jones8ff69732006-03-05 03:37:23 -050011 * Feb 2006 - Jacob Shin <jacob.shin@amd.com>
12 * Fix handling for CPU hotplug -- affected CPUs
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 */
14
Viresh Kumardb701152012-10-23 01:29:03 +020015#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
Viresh Kumar5ff0a262013-08-06 22:53:03 +053017#include <linux/cpu.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/cpufreq.h>
Amit Kucheria5c238a82019-01-30 10:52:01 +053019#include <linux/cpu_cooling.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/delay.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/device.h>
Viresh Kumar5ff0a262013-08-06 22:53:03 +053022#include <linux/init.h>
23#include <linux/kernel_stat.h>
24#include <linux/module.h>
akpm@osdl.org3fc54d32006-01-13 15:54:22 -080025#include <linux/mutex.h>
Viresh Kumar67d874c2019-07-08 16:27:52 +053026#include <linux/pm_qos.h>
Viresh Kumar5ff0a262013-08-06 22:53:03 +053027#include <linux/slab.h>
Viresh Kumar2f0aea92014-03-04 11:00:26 +080028#include <linux/suspend.h>
Doug Anderson90de2a42014-12-23 22:09:48 -080029#include <linux/syscore_ops.h>
Viresh Kumar5ff0a262013-08-06 22:53:03 +053030#include <linux/tick.h>
Thomas Renninger6f4f2722010-04-20 13:17:36 +020031#include <trace/events/power.h>
32
Viresh Kumarb4f06762015-01-27 14:06:08 +053033static LIST_HEAD(cpufreq_policy_list);
Viresh Kumarf9637352015-05-12 12:20:11 +053034
Viresh Kumarf9637352015-05-12 12:20:11 +053035/* Macros to iterate over CPU policies */
Eric Biggersfd7dc7e2016-02-21 12:53:12 -060036#define for_each_suitable_policy(__policy, __active) \
37 list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \
38 if ((__active) == !policy_is_inactive(__policy))
Viresh Kumarf9637352015-05-12 12:20:11 +053039
40#define for_each_active_policy(__policy) \
41 for_each_suitable_policy(__policy, true)
42#define for_each_inactive_policy(__policy) \
43 for_each_suitable_policy(__policy, false)
44
45#define for_each_policy(__policy) \
Viresh Kumarb4f06762015-01-27 14:06:08 +053046 list_for_each_entry(__policy, &cpufreq_policy_list, policy_list)
47
Viresh Kumarf7b27062015-01-27 14:06:09 +053048/* Iterate over governors */
49static LIST_HEAD(cpufreq_governor_list);
50#define for_each_governor(__governor) \
51 list_for_each_entry(__governor, &cpufreq_governor_list, governor_list)
52
Linus Torvalds1da177e2005-04-16 15:20:36 -070053/**
Dave Jonescd878472006-08-11 17:59:28 -040054 * The "cpufreq driver" - the arch- or hardware-dependent low
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 * level driver of CPUFreq support, and its spinlock. This lock
56 * also protects the cpufreq_cpu_data array.
57 */
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +020058static struct cpufreq_driver *cpufreq_driver;
Mike Travis7a6aedf2008-03-25 15:06:53 -070059static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
Viresh Kumarbb176f72013-06-19 14:19:33 +053060static DEFINE_RWLOCK(cpufreq_driver_lock);
Viresh Kumarbb176f72013-06-19 14:19:33 +053061
Viresh Kumar2f0aea92014-03-04 11:00:26 +080062/* Flag to suspend/resume CPUFreq governors */
63static bool cpufreq_suspended;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +053065static inline bool has_target(void)
66{
67 return cpufreq_driver->target_index || cpufreq_driver->target;
68}
69
Linus Torvalds1da177e2005-04-16 15:20:36 -070070/* internal prototypes */
Viresh Kumard92d50a2015-01-02 12:34:29 +053071static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
Rafael J. Wysockia92604b2016-05-14 01:01:46 +020072static int cpufreq_init_governor(struct cpufreq_policy *policy);
73static void cpufreq_exit_governor(struct cpufreq_policy *policy);
Rafael J. Wysocki0a300762016-03-21 15:45:24 +010074static int cpufreq_start_governor(struct cpufreq_policy *policy);
Rafael J. Wysockia92604b2016-05-14 01:01:46 +020075static void cpufreq_stop_governor(struct cpufreq_policy *policy);
76static void cpufreq_governor_limits(struct cpufreq_policy *policy);
Rafael J. Wysocki45482c72016-05-12 15:14:12 +020077
Linus Torvalds1da177e2005-04-16 15:20:36 -070078/**
Dave Jones32ee8c32006-02-28 00:43:23 -050079 * Two notifier lists: the "policy" list is involved in the
80 * validation process for a new CPU frequency policy; the
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 * "transition" list for kernel code that needs to handle
82 * changes to devices when the CPU clock speed changes.
83 * The mutex locks both lists.
84 */
Alan Sterne041c682006-03-27 01:16:30 -080085static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
Sebastian Andrzej Siewiorcc85de32018-05-25 12:19:58 +020086SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -070087
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -040088static int off __read_mostly;
Viresh Kumarda584452012-10-26 00:51:32 +020089static int cpufreq_disabled(void)
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -040090{
91 return off;
92}
93void disable_cpufreq(void)
94{
95 off = 1;
96}
Dave Jones29464f22009-01-18 01:37:11 -050097static DEFINE_MUTEX(cpufreq_governor_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098
Viresh Kumar4d5dcc42013-03-27 15:58:58 +000099bool have_governor_per_policy(void)
100{
Viresh Kumar0b981e72013-10-02 14:13:18 +0530101 return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000102}
Viresh Kumar3f869d62013-05-16 05:09:56 +0000103EXPORT_SYMBOL_GPL(have_governor_per_policy);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +0000104
Viresh Kumar944e9a02013-05-16 05:09:57 +0000105struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy)
106{
107 if (have_governor_per_policy())
108 return &policy->kobj;
109 else
110 return cpufreq_global_kobject;
111}
112EXPORT_SYMBOL_GPL(get_governor_parent_kobj);
113
Viresh Kumar72a4ce32013-05-17 11:26:32 +0000114static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
115{
116 u64 idle_time;
117 u64 cur_wall_time;
118 u64 busy_time;
119
Frederic Weisbecker7fb13272017-01-31 04:09:19 +0100120 cur_wall_time = jiffies64_to_nsecs(get_jiffies_64());
Viresh Kumar72a4ce32013-05-17 11:26:32 +0000121
122 busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER];
123 busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM];
124 busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ];
125 busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ];
126 busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL];
127 busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE];
128
129 idle_time = cur_wall_time - busy_time;
130 if (wall)
Frederic Weisbecker7fb13272017-01-31 04:09:19 +0100131 *wall = div_u64(cur_wall_time, NSEC_PER_USEC);
Viresh Kumar72a4ce32013-05-17 11:26:32 +0000132
Frederic Weisbecker7fb13272017-01-31 04:09:19 +0100133 return div_u64(idle_time, NSEC_PER_USEC);
Viresh Kumar72a4ce32013-05-17 11:26:32 +0000134}
135
136u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy)
137{
138 u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL);
139
140 if (idle_time == -1ULL)
141 return get_cpu_idle_time_jiffy(cpu, wall);
142 else if (!io_busy)
143 idle_time += get_cpu_iowait_time_us(cpu, wall);
144
145 return idle_time;
146}
147EXPORT_SYMBOL_GPL(get_cpu_idle_time);
148
Dietmar Eggemanne7d54592017-09-26 17:41:07 +0100149__weak void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq,
150 unsigned long max_freq)
151{
152}
153EXPORT_SYMBOL_GPL(arch_set_freq_scale);
154
Viresh Kumar70e9e772013-10-03 20:29:07 +0530155/*
156 * This is a generic cpufreq init() routine which can be used by cpufreq
157 * drivers of SMP systems. It will do following:
158 * - validate & show freq table passed
159 * - set policies transition latency
160 * - policy->cpus with all possible CPUs
161 */
Viresh Kumarc4dcc8a2019-07-16 09:36:08 +0530162void cpufreq_generic_init(struct cpufreq_policy *policy,
Viresh Kumar70e9e772013-10-03 20:29:07 +0530163 struct cpufreq_frequency_table *table,
164 unsigned int transition_latency)
165{
Viresh Kumar92c99d12018-02-26 10:38:45 +0530166 policy->freq_table = table;
Viresh Kumar70e9e772013-10-03 20:29:07 +0530167 policy->cpuinfo.transition_latency = transition_latency;
168
169 /*
Shailendra Verma58405af2015-05-22 22:48:22 +0530170 * The driver only supports the SMP configuration where all processors
Viresh Kumar70e9e772013-10-03 20:29:07 +0530171 * share the clock and voltage and clock.
172 */
173 cpumask_setall(policy->cpus);
Viresh Kumar70e9e772013-10-03 20:29:07 +0530174}
175EXPORT_SYMBOL_GPL(cpufreq_generic_init);
176
Rafael J. Wysocki1f0bd442015-09-16 02:17:49 +0200177struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
Viresh Kumar652ed952014-01-09 20:38:43 +0530178{
179 struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
180
Viresh Kumar988bed02015-05-08 11:53:45 +0530181 return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL;
182}
Rafael J. Wysocki1f0bd442015-09-16 02:17:49 +0200183EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw);
Viresh Kumar988bed02015-05-08 11:53:45 +0530184
185unsigned int cpufreq_generic_get(unsigned int cpu)
186{
187 struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
188
Viresh Kumar652ed952014-01-09 20:38:43 +0530189 if (!policy || IS_ERR(policy->clk)) {
Joe Perchese837f9b2014-03-11 10:03:00 -0700190 pr_err("%s: No %s associated to cpu: %d\n",
191 __func__, policy ? "clk" : "policy", cpu);
Viresh Kumar652ed952014-01-09 20:38:43 +0530192 return 0;
193 }
194
195 return clk_get_rate(policy->clk) / 1000;
196}
197EXPORT_SYMBOL_GPL(cpufreq_generic_get);
198
Viresh Kumar50e9c852015-02-19 17:02:03 +0530199/**
Rafael J. Wysocki5d094fe2019-03-05 11:44:04 +0100200 * cpufreq_cpu_get - Return policy for a CPU and mark it as busy.
201 * @cpu: CPU to find the policy for.
Viresh Kumar50e9c852015-02-19 17:02:03 +0530202 *
Rafael J. Wysocki5d094fe2019-03-05 11:44:04 +0100203 * Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment
204 * the kobject reference counter of that policy. Return a valid policy on
205 * success or NULL on failure.
Viresh Kumar50e9c852015-02-19 17:02:03 +0530206 *
Rafael J. Wysocki5d094fe2019-03-05 11:44:04 +0100207 * The policy returned by this function has to be released with the help of
208 * cpufreq_cpu_put() to balance its kobject reference counter properly.
Viresh Kumar50e9c852015-02-19 17:02:03 +0530209 */
Viresh Kumar6eed9402013-08-06 22:53:11 +0530210struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211{
Viresh Kumar6eed9402013-08-06 22:53:11 +0530212 struct cpufreq_policy *policy = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 unsigned long flags;
214
Viresh Kumar1b947c902015-02-19 17:02:05 +0530215 if (WARN_ON(cpu >= nr_cpu_ids))
Viresh Kumar6eed9402013-08-06 22:53:11 +0530216 return NULL;
217
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 /* get the cpufreq driver */
Nathan Zimmer0d1857a2013-02-22 16:24:34 +0000219 read_lock_irqsave(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220
Viresh Kumar6eed9402013-08-06 22:53:11 +0530221 if (cpufreq_driver) {
222 /* get the CPU */
Viresh Kumar988bed02015-05-08 11:53:45 +0530223 policy = cpufreq_cpu_get_raw(cpu);
Viresh Kumar6eed9402013-08-06 22:53:11 +0530224 if (policy)
225 kobject_get(&policy->kobj);
226 }
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200227
Viresh Kumar6eed9402013-08-06 22:53:11 +0530228 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229
Viresh Kumar3a3e9e02013-08-06 22:53:05 +0530230 return policy;
Stephen Boyda9144432012-07-20 18:14:38 +0000231}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
233
Viresh Kumar50e9c852015-02-19 17:02:03 +0530234/**
Rafael J. Wysocki5d094fe2019-03-05 11:44:04 +0100235 * cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy.
236 * @policy: cpufreq policy returned by cpufreq_cpu_get().
Viresh Kumar50e9c852015-02-19 17:02:03 +0530237 */
Viresh Kumar3a3e9e02013-08-06 22:53:05 +0530238void cpufreq_cpu_put(struct cpufreq_policy *policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239{
Viresh Kumar6eed9402013-08-06 22:53:11 +0530240 kobject_put(&policy->kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241}
242EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
243
Rafael J. Wysocki540a37582019-03-26 12:16:58 +0100244/**
245 * cpufreq_cpu_release - Unlock a policy and decrement its usage counter.
246 * @policy: cpufreq policy returned by cpufreq_cpu_acquire().
247 */
Rafael J. Wysocki9083e492019-03-26 12:19:52 +0100248void cpufreq_cpu_release(struct cpufreq_policy *policy)
Rafael J. Wysocki540a37582019-03-26 12:16:58 +0100249{
250 if (WARN_ON(!policy))
251 return;
252
253 lockdep_assert_held(&policy->rwsem);
254
255 up_write(&policy->rwsem);
256
257 cpufreq_cpu_put(policy);
258}
259
260/**
261 * cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it.
262 * @cpu: CPU to find the policy for.
263 *
264 * Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and
265 * if the policy returned by it is not NULL, acquire its rwsem for writing.
266 * Return the policy if it is active or release it and return NULL otherwise.
267 *
268 * The policy returned by this function has to be released with the help of
269 * cpufreq_cpu_release() in order to release its rwsem and balance its usage
270 * counter properly.
271 */
Rafael J. Wysocki9083e492019-03-26 12:19:52 +0100272struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu)
Rafael J. Wysocki540a37582019-03-26 12:16:58 +0100273{
274 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
275
276 if (!policy)
277 return NULL;
278
279 down_write(&policy->rwsem);
280
281 if (policy_is_inactive(policy)) {
282 cpufreq_cpu_release(policy);
283 return NULL;
284 }
285
286 return policy;
287}
288
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289/*********************************************************************
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 * EXTERNALLY AFFECTING FREQUENCY CHANGES *
291 *********************************************************************/
292
293/**
294 * adjust_jiffies - adjust the system "loops_per_jiffy"
295 *
296 * This function alters the system "loops_per_jiffy" for the clock
297 * speed change. Note that loops_per_jiffy cannot be updated on SMP
Dave Jones32ee8c32006-02-28 00:43:23 -0500298 * systems as each CPU might be scaled differently. So, use the arch
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 * per-CPU loops_per_jiffy value wherever possible.
300 */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800301static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302{
Viresh Kumar39c132e2015-01-02 12:34:34 +0530303#ifndef CONFIG_SMP
304 static unsigned long l_p_j_ref;
305 static unsigned int l_p_j_ref_freq;
306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 if (ci->flags & CPUFREQ_CONST_LOOPS)
308 return;
309
310 if (!l_p_j_ref_freq) {
311 l_p_j_ref = loops_per_jiffy;
312 l_p_j_ref_freq = ci->old;
Joe Perchese837f9b2014-03-11 10:03:00 -0700313 pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n",
314 l_p_j_ref, l_p_j_ref_freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 }
Viresh Kumar0b443ea2014-03-19 11:24:58 +0530316 if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) {
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530317 loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
318 ci->new);
Joe Perchese837f9b2014-03-11 10:03:00 -0700319 pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n",
320 loops_per_jiffy, ci->new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322#endif
Viresh Kumar39c132e2015-01-02 12:34:34 +0530323}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324
Viresh Kumar20b53242018-05-10 15:00:29 +0530325/**
326 * cpufreq_notify_transition - Notify frequency transition and adjust_jiffies.
327 * @policy: cpufreq policy to enable fast frequency switching for.
328 * @freqs: contain details of the frequency update.
329 * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE.
330 *
331 * This function calls the transition notifiers and the "adjust_jiffies"
332 * function. It is called twice on all CPU frequency changes that have
333 * external effects.
334 */
335static void cpufreq_notify_transition(struct cpufreq_policy *policy,
336 struct cpufreq_freqs *freqs,
337 unsigned int state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338{
Viresh Kumardf240142019-04-29 15:03:58 +0530339 int cpu;
340
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 BUG_ON(irqs_disabled());
342
Dirk Brandewied5aaffa2013-01-17 16:22:21 +0000343 if (cpufreq_disabled())
344 return;
345
Viresh Kumardf240142019-04-29 15:03:58 +0530346 freqs->policy = policy;
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200347 freqs->flags = cpufreq_driver->flags;
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200348 pr_debug("notification %u of frequency transition to %u kHz\n",
Joe Perchese837f9b2014-03-11 10:03:00 -0700349 state, freqs->new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 switch (state) {
352 case CPUFREQ_PRECHANGE:
Viresh Kumar20b53242018-05-10 15:00:29 +0530353 /*
354 * Detect if the driver reported a value as "old frequency"
Dave Jonese4472cb2006-01-31 15:53:55 -0800355 * which is not equal to what the cpufreq core thinks is
356 * "old frequency".
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 */
Viresh Kumar98015222019-06-28 10:46:55 +0530358 if (policy->cur && policy->cur != freqs->old) {
359 pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n",
360 freqs->old, policy->cur);
361 freqs->old = policy->cur;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 }
Viresh Kumar20b53242018-05-10 15:00:29 +0530363
Viresh Kumardf240142019-04-29 15:03:58 +0530364 srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
365 CPUFREQ_PRECHANGE, freqs);
Viresh Kumar20b53242018-05-10 15:00:29 +0530366
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
368 break;
Dave Jonese4472cb2006-01-31 15:53:55 -0800369
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 case CPUFREQ_POSTCHANGE:
371 adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
Viresh Kumar20b53242018-05-10 15:00:29 +0530372 pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new,
373 cpumask_pr_args(policy->cpus));
Viresh Kumarbb176f72013-06-19 14:19:33 +0530374
Viresh Kumardf240142019-04-29 15:03:58 +0530375 for_each_cpu(cpu, policy->cpus)
376 trace_cpu_frequency(freqs->new, cpu);
377
378 srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
379 CPUFREQ_POSTCHANGE, freqs);
Viresh Kumar20b53242018-05-10 15:00:29 +0530380
381 cpufreq_stats_record_transition(policy, freqs->new);
382 policy->cur = freqs->new;
383 }
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530384}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385
Viresh Kumarf7ba3b42013-12-02 11:04:12 +0530386/* Do post notifications when there are chances that transition has failed */
Viresh Kumar236a9802014-03-24 13:35:46 +0530387static void cpufreq_notify_post_transition(struct cpufreq_policy *policy,
Viresh Kumarf7ba3b42013-12-02 11:04:12 +0530388 struct cpufreq_freqs *freqs, int transition_failed)
389{
390 cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
391 if (!transition_failed)
392 return;
393
394 swap(freqs->old, freqs->new);
395 cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
396 cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
397}
Viresh Kumarf7ba3b42013-12-02 11:04:12 +0530398
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530399void cpufreq_freq_transition_begin(struct cpufreq_policy *policy,
400 struct cpufreq_freqs *freqs)
401{
Srivatsa S. Bhatca654dc2014-05-05 12:52:39 +0530402
403 /*
404 * Catch double invocations of _begin() which lead to self-deadlock.
405 * ASYNC_NOTIFICATION drivers are left out because the cpufreq core
406 * doesn't invoke _begin() on their behalf, and hence the chances of
407 * double invocations are very low. Moreover, there are scenarios
408 * where these checks can emit false-positive warnings in these
409 * drivers; so we avoid that by skipping them altogether.
410 */
411 WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION)
412 && current == policy->transition_task);
413
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530414wait:
415 wait_event(policy->transition_wait, !policy->transition_ongoing);
416
417 spin_lock(&policy->transition_lock);
418
419 if (unlikely(policy->transition_ongoing)) {
420 spin_unlock(&policy->transition_lock);
421 goto wait;
422 }
423
424 policy->transition_ongoing = true;
Srivatsa S. Bhatca654dc2014-05-05 12:52:39 +0530425 policy->transition_task = current;
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530426
427 spin_unlock(&policy->transition_lock);
428
429 cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
430}
431EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin);
432
433void cpufreq_freq_transition_end(struct cpufreq_policy *policy,
434 struct cpufreq_freqs *freqs, int transition_failed)
435{
Igor Stoppa0e7ea2f2018-09-07 19:09:55 +0300436 if (WARN_ON(!policy->transition_ongoing))
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530437 return;
438
439 cpufreq_notify_post_transition(policy, freqs, transition_failed);
440
441 policy->transition_ongoing = false;
Srivatsa S. Bhatca654dc2014-05-05 12:52:39 +0530442 policy->transition_task = NULL;
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530443
444 wake_up(&policy->transition_wait);
445}
446EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end);
447
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +0200448/*
449 * Fast frequency switching status count. Positive means "enabled", negative
450 * means "disabled" and 0 means "not decided yet".
451 */
452static int cpufreq_fast_switch_count;
453static DEFINE_MUTEX(cpufreq_fast_switch_lock);
454
455static void cpufreq_list_transition_notifiers(void)
456{
457 struct notifier_block *nb;
458
459 pr_info("Registered transition notifiers:\n");
460
461 mutex_lock(&cpufreq_transition_notifier_list.mutex);
462
463 for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next)
Sakari Ailusd75f7732019-03-25 21:32:28 +0200464 pr_info("%pS\n", nb->notifier_call);
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +0200465
466 mutex_unlock(&cpufreq_transition_notifier_list.mutex);
467}
468
469/**
470 * cpufreq_enable_fast_switch - Enable fast frequency switching for policy.
471 * @policy: cpufreq policy to enable fast frequency switching for.
472 *
473 * Try to enable fast frequency switching for @policy.
474 *
475 * The attempt will fail if there is at least one transition notifier registered
476 * at this point, as fast frequency switching is quite fundamentally at odds
477 * with transition notifiers. Thus if successful, it will make registration of
478 * transition notifiers fail going forward.
479 */
480void cpufreq_enable_fast_switch(struct cpufreq_policy *policy)
481{
482 lockdep_assert_held(&policy->rwsem);
483
484 if (!policy->fast_switch_possible)
485 return;
486
487 mutex_lock(&cpufreq_fast_switch_lock);
488 if (cpufreq_fast_switch_count >= 0) {
489 cpufreq_fast_switch_count++;
490 policy->fast_switch_enabled = true;
491 } else {
492 pr_warn("CPU%u: Fast frequency switching not enabled\n",
493 policy->cpu);
494 cpufreq_list_transition_notifiers();
495 }
496 mutex_unlock(&cpufreq_fast_switch_lock);
497}
498EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch);
499
Rafael J. Wysocki6c9d9c82016-04-07 23:38:46 +0200500/**
501 * cpufreq_disable_fast_switch - Disable fast frequency switching for policy.
502 * @policy: cpufreq policy to disable fast frequency switching for.
503 */
504void cpufreq_disable_fast_switch(struct cpufreq_policy *policy)
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +0200505{
506 mutex_lock(&cpufreq_fast_switch_lock);
507 if (policy->fast_switch_enabled) {
508 policy->fast_switch_enabled = false;
509 if (!WARN_ON(cpufreq_fast_switch_count <= 0))
510 cpufreq_fast_switch_count--;
511 }
512 mutex_unlock(&cpufreq_fast_switch_lock);
513}
Rafael J. Wysocki6c9d9c82016-04-07 23:38:46 +0200514EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515
Steve Mucklee3c06232016-07-13 13:25:25 -0700516/**
517 * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported
518 * one.
519 * @target_freq: target frequency to resolve.
520 *
521 * The target to driver frequency mapping is cached in the policy.
522 *
523 * Return: Lowest driver-supported frequency greater than or equal to the
524 * given target_freq, subject to policy (min/max) and driver limitations.
525 */
526unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy,
527 unsigned int target_freq)
528{
529 target_freq = clamp_val(target_freq, policy->min, policy->max);
530 policy->cached_target_freq = target_freq;
Viresh Kumarabe8bd02016-07-21 14:39:26 -0700531
532 if (cpufreq_driver->target_index) {
533 int idx;
534
535 idx = cpufreq_frequency_table_target(policy, target_freq,
536 CPUFREQ_RELATION_L);
537 policy->cached_resolved_idx = idx;
538 return policy->freq_table[idx].frequency;
539 }
540
Steve Mucklee3c06232016-07-13 13:25:25 -0700541 if (cpufreq_driver->resolve_freq)
542 return cpufreq_driver->resolve_freq(policy, target_freq);
Viresh Kumarabe8bd02016-07-21 14:39:26 -0700543
544 return target_freq;
Steve Mucklee3c06232016-07-13 13:25:25 -0700545}
Steve Muckleae2c1ca2016-07-21 19:24:38 -0700546EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq);
Steve Mucklee3c06232016-07-13 13:25:25 -0700547
Viresh Kumaraa7519a2017-07-19 15:42:42 +0530548unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy)
549{
550 unsigned int latency;
551
552 if (policy->transition_delay_us)
553 return policy->transition_delay_us;
554
555 latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC;
Viresh Kumare948bc82017-08-17 09:12:27 +0530556 if (latency) {
557 /*
558 * For platforms that can change the frequency very fast (< 10
559 * us), the above formula gives a decent transition delay. But
560 * for platforms where transition_latency is in milliseconds, it
561 * ends up giving unrealistic values.
562 *
563 * Cap the default transition delay to 10 ms, which seems to be
564 * a reasonable amount of time after which we should reevaluate
565 * the frequency.
566 */
567 return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000);
568 }
Viresh Kumaraa7519a2017-07-19 15:42:42 +0530569
570 return LATENCY_MULTIPLIER;
571}
572EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us);
573
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574/*********************************************************************
575 * SYSFS INTERFACE *
576 *********************************************************************/
Rashika Kheria8a5c74a2014-02-26 22:12:42 +0530577static ssize_t show_boost(struct kobject *kobj,
Viresh Kumar625c85a2019-01-25 12:53:07 +0530578 struct kobj_attribute *attr, char *buf)
Lukasz Majewski6f19efc2013-12-20 15:24:49 +0100579{
580 return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled);
581}
582
Viresh Kumar625c85a2019-01-25 12:53:07 +0530583static ssize_t store_boost(struct kobject *kobj, struct kobj_attribute *attr,
584 const char *buf, size_t count)
Lukasz Majewski6f19efc2013-12-20 15:24:49 +0100585{
586 int ret, enable;
587
588 ret = sscanf(buf, "%d", &enable);
589 if (ret != 1 || enable < 0 || enable > 1)
590 return -EINVAL;
591
592 if (cpufreq_boost_trigger_state(enable)) {
Joe Perchese837f9b2014-03-11 10:03:00 -0700593 pr_err("%s: Cannot %s BOOST!\n",
594 __func__, enable ? "enable" : "disable");
Lukasz Majewski6f19efc2013-12-20 15:24:49 +0100595 return -EINVAL;
596 }
597
Joe Perchese837f9b2014-03-11 10:03:00 -0700598 pr_debug("%s: cpufreq BOOST %s\n",
599 __func__, enable ? "enabled" : "disabled");
Lukasz Majewski6f19efc2013-12-20 15:24:49 +0100600
601 return count;
602}
603define_one_global_rw(boost);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604
Viresh Kumar42f91fa2015-01-02 12:34:26 +0530605static struct cpufreq_governor *find_governor(const char *str_governor)
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700606{
607 struct cpufreq_governor *t;
608
Viresh Kumarf7b27062015-01-27 14:06:09 +0530609 for_each_governor(t)
Rasmus Villemoes7c4f4532014-09-29 15:50:11 +0200610 if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN))
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700611 return t;
612
613 return NULL;
614}
615
Yue Huab05d972019-04-29 15:24:18 +0800616static int cpufreq_parse_policy(char *str_governor,
617 struct cpufreq_policy *policy)
618{
619 if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) {
620 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
621 return 0;
622 }
623 if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) {
624 policy->policy = CPUFREQ_POLICY_POWERSAVE;
625 return 0;
626 }
627 return -EINVAL;
628}
629
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630/**
Viresh Kumar5ddc6d42019-06-20 08:35:48 +0530631 * cpufreq_parse_governor - parse a governor string only for has_target()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 */
Rafael J. Wysockiae0ff892017-11-23 01:24:05 +0100633static int cpufreq_parse_governor(char *str_governor,
634 struct cpufreq_policy *policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635{
Yue Huab05d972019-04-29 15:24:18 +0800636 struct cpufreq_governor *t;
Rafael J. Wysocki045149e2017-11-23 01:23:16 +0100637
Yue Huab05d972019-04-29 15:24:18 +0800638 mutex_lock(&cpufreq_governor_mutex);
639
640 t = find_governor(str_governor);
641 if (!t) {
642 int ret;
643
644 mutex_unlock(&cpufreq_governor_mutex);
645
646 ret = request_module("cpufreq_%s", str_governor);
647 if (ret)
648 return -EINVAL;
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700649
akpm@osdl.org3fc54d32006-01-13 15:54:22 -0800650 mutex_lock(&cpufreq_governor_mutex);
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700651
Viresh Kumar42f91fa2015-01-02 12:34:26 +0530652 t = find_governor(str_governor);
Yue Huab05d972019-04-29 15:24:18 +0800653 }
654 if (t && !try_module_get(t->owner))
655 t = NULL;
Jeremy Fitzhardingeea714972006-07-06 12:32:01 -0700656
Yue Huab05d972019-04-29 15:24:18 +0800657 mutex_unlock(&cpufreq_governor_mutex);
Rafael J. Wysocki045149e2017-11-23 01:23:16 +0100658
Yue Huab05d972019-04-29 15:24:18 +0800659 if (t) {
660 policy->governor = t;
661 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 }
Rafael J. Wysocki045149e2017-11-23 01:23:16 +0100663
664 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667/**
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530668 * cpufreq_per_cpu_attr_read() / show_##file_name() -
669 * print out cpufreq information
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670 *
671 * Write out information from cpufreq_driver->policy[cpu]; object must be
672 * "unsigned int".
673 */
674
Dave Jones32ee8c32006-02-28 00:43:23 -0500675#define show_one(file_name, object) \
676static ssize_t show_##file_name \
Dave Jones905d77c2008-03-05 14:28:32 -0500677(struct cpufreq_policy *policy, char *buf) \
Dave Jones32ee8c32006-02-28 00:43:23 -0500678{ \
Dave Jones29464f22009-01-18 01:37:11 -0500679 return sprintf(buf, "%u\n", policy->object); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680}
681
682show_one(cpuinfo_min_freq, cpuinfo.min_freq);
683show_one(cpuinfo_max_freq, cpuinfo.max_freq);
Thomas Renningered129782009-02-04 01:17:41 +0100684show_one(cpuinfo_transition_latency, cpuinfo.transition_latency);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685show_one(scaling_min_freq, min);
686show_one(scaling_max_freq, max);
Dirk Brandewiec034b022014-10-13 08:37:40 -0700687
Len Brownf8475ce2017-06-23 22:11:52 -0700688__weak unsigned int arch_freq_get_on_cpu(int cpu)
689{
690 return 0;
691}
692
Viresh Kumar09347b22015-01-02 12:34:24 +0530693static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf)
Dirk Brandewiec034b022014-10-13 08:37:40 -0700694{
695 ssize_t ret;
Len Brownf8475ce2017-06-23 22:11:52 -0700696 unsigned int freq;
Dirk Brandewiec034b022014-10-13 08:37:40 -0700697
Len Brownf8475ce2017-06-23 22:11:52 -0700698 freq = arch_freq_get_on_cpu(policy->cpu);
699 if (freq)
700 ret = sprintf(buf, "%u\n", freq);
701 else if (cpufreq_driver && cpufreq_driver->setpolicy &&
702 cpufreq_driver->get)
Dirk Brandewiec034b022014-10-13 08:37:40 -0700703 ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu));
704 else
705 ret = sprintf(buf, "%u\n", policy->cur);
706 return ret;
707}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708
709/**
710 * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access
711 */
712#define store_one(file_name, object) \
713static ssize_t store_##file_name \
Dave Jones905d77c2008-03-05 14:28:32 -0500714(struct cpufreq_policy *policy, const char *buf, size_t count) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715{ \
Viresh Kumar18c49922019-07-05 16:21:24 +0530716 unsigned long val; \
717 int ret; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718 \
Viresh Kumar18c49922019-07-05 16:21:24 +0530719 ret = sscanf(buf, "%lu", &val); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720 if (ret != 1) \
721 return -EINVAL; \
722 \
Viresh Kumar18c49922019-07-05 16:21:24 +0530723 ret = dev_pm_qos_update_request(policy->object##_freq_req, val);\
724 return ret >= 0 ? count : ret; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725}
726
Dave Jones29464f22009-01-18 01:37:11 -0500727store_one(scaling_min_freq, min);
728store_one(scaling_max_freq, max);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729
730/**
731 * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware
732 */
Dave Jones905d77c2008-03-05 14:28:32 -0500733static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy,
734 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735{
Viresh Kumard92d50a2015-01-02 12:34:29 +0530736 unsigned int cur_freq = __cpufreq_get(policy);
Rafael J. Wysocki9b4f6032017-03-15 00:12:16 +0100737
738 if (cur_freq)
739 return sprintf(buf, "%u\n", cur_freq);
740
741 return sprintf(buf, "<unknown>\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742}
743
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744/**
745 * show_scaling_governor - show the current policy for the specified CPU
746 */
Dave Jones905d77c2008-03-05 14:28:32 -0500747static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748{
Dave Jones29464f22009-01-18 01:37:11 -0500749 if (policy->policy == CPUFREQ_POLICY_POWERSAVE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750 return sprintf(buf, "powersave\n");
751 else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE)
752 return sprintf(buf, "performance\n");
753 else if (policy->governor)
viresh kumar4b972f02012-10-23 01:23:43 +0200754 return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n",
Dave Jones29464f22009-01-18 01:37:11 -0500755 policy->governor->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756 return -EINVAL;
757}
758
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759/**
760 * store_scaling_governor - store policy for the specified CPU
761 */
Dave Jones905d77c2008-03-05 14:28:32 -0500762static ssize_t store_scaling_governor(struct cpufreq_policy *policy,
763 const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764{
Srivatsa S. Bhat5136fa52013-09-07 01:24:06 +0530765 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 char str_governor[16];
767 struct cpufreq_policy new_policy;
768
Viresh Kumar8fa5b632015-08-03 08:36:15 +0530769 memcpy(&new_policy, policy, sizeof(*policy));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770
Dave Jones29464f22009-01-18 01:37:11 -0500771 ret = sscanf(buf, "%15s", str_governor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772 if (ret != 1)
773 return -EINVAL;
774
Yue Huab05d972019-04-29 15:24:18 +0800775 if (cpufreq_driver->setpolicy) {
776 if (cpufreq_parse_policy(str_governor, &new_policy))
777 return -EINVAL;
778 } else {
779 if (cpufreq_parse_governor(str_governor, &new_policy))
780 return -EINVAL;
781 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782
Viresh Kumar037ce832013-10-02 14:13:16 +0530783 ret = cpufreq_set_policy(policy, &new_policy);
Rafael J. Wysockia8b149d2017-11-23 14:27:07 +0100784
785 if (new_policy.governor)
786 module_put(new_policy.governor->owner);
787
Viresh Kumar88dc4382015-08-03 08:36:18 +0530788 return ret ? ret : count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789}
790
791/**
792 * show_scaling_driver - show the cpufreq driver currently loaded
793 */
Dave Jones905d77c2008-03-05 14:28:32 -0500794static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795{
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200796 return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797}
798
799/**
800 * show_scaling_available_governors - show the available CPUfreq governors
801 */
Dave Jones905d77c2008-03-05 14:28:32 -0500802static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy,
803 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804{
805 ssize_t i = 0;
806 struct cpufreq_governor *t;
807
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530808 if (!has_target()) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809 i += sprintf(buf, "performance powersave");
810 goto out;
811 }
812
Viresh Kumarf7b27062015-01-27 14:06:09 +0530813 for_each_governor(t) {
Dave Jones29464f22009-01-18 01:37:11 -0500814 if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char))
815 - (CPUFREQ_NAME_LEN + 2)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 goto out;
viresh kumar4b972f02012-10-23 01:23:43 +0200817 i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 }
Dave Jones7d5e3502006-02-02 17:03:42 -0500819out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 i += sprintf(&buf[i], "\n");
821 return i;
822}
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700823
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800824ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825{
826 ssize_t i = 0;
827 unsigned int cpu;
828
Rusty Russell835481d2009-01-04 05:18:06 -0800829 for_each_cpu(cpu, mask) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830 if (i)
831 i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " ");
832 i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu);
833 if (i >= (PAGE_SIZE - 5))
Dave Jones29464f22009-01-18 01:37:11 -0500834 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 }
836 i += sprintf(&buf[i], "\n");
837 return i;
838}
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800839EXPORT_SYMBOL_GPL(cpufreq_show_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700841/**
842 * show_related_cpus - show the CPUs affected by each transition even if
843 * hw coordination is in use
844 */
845static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
846{
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800847 return cpufreq_show_cpus(policy->related_cpus, buf);
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700848}
849
850/**
851 * show_affected_cpus - show the CPUs affected by each transition
852 */
853static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf)
854{
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800855 return cpufreq_show_cpus(policy->cpus, buf);
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700856}
857
Venki Pallipadi9e769882007-10-26 10:18:21 -0700858static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
Dave Jones905d77c2008-03-05 14:28:32 -0500859 const char *buf, size_t count)
Venki Pallipadi9e769882007-10-26 10:18:21 -0700860{
861 unsigned int freq = 0;
862 unsigned int ret;
863
CHIKAMA masaki879000f2008-06-05 22:46:33 -0700864 if (!policy->governor || !policy->governor->store_setspeed)
Venki Pallipadi9e769882007-10-26 10:18:21 -0700865 return -EINVAL;
866
867 ret = sscanf(buf, "%u", &freq);
868 if (ret != 1)
869 return -EINVAL;
870
871 policy->governor->store_setspeed(policy, freq);
872
873 return count;
874}
875
876static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf)
877{
CHIKAMA masaki879000f2008-06-05 22:46:33 -0700878 if (!policy->governor || !policy->governor->show_setspeed)
Venki Pallipadi9e769882007-10-26 10:18:21 -0700879 return sprintf(buf, "<unsupported>\n");
880
881 return policy->governor->show_setspeed(policy, buf);
882}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883
Thomas Renningere2f74f32009-11-19 12:31:01 +0100884/**
viresh kumar8bf1ac722012-10-23 01:23:33 +0200885 * show_bios_limit - show the current cpufreq HW/BIOS limitation
Thomas Renningere2f74f32009-11-19 12:31:01 +0100886 */
887static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf)
888{
889 unsigned int limit;
890 int ret;
Yue Hub23aa312019-04-16 10:40:27 +0800891 ret = cpufreq_driver->bios_limit(policy->cpu, &limit);
892 if (!ret)
893 return sprintf(buf, "%u\n", limit);
Thomas Renningere2f74f32009-11-19 12:31:01 +0100894 return sprintf(buf, "%u\n", policy->cpuinfo.max_freq);
895}
896
Borislav Petkov6dad2a22010-03-31 21:56:46 +0200897cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400);
898cpufreq_freq_attr_ro(cpuinfo_min_freq);
899cpufreq_freq_attr_ro(cpuinfo_max_freq);
900cpufreq_freq_attr_ro(cpuinfo_transition_latency);
901cpufreq_freq_attr_ro(scaling_available_governors);
902cpufreq_freq_attr_ro(scaling_driver);
903cpufreq_freq_attr_ro(scaling_cur_freq);
904cpufreq_freq_attr_ro(bios_limit);
905cpufreq_freq_attr_ro(related_cpus);
906cpufreq_freq_attr_ro(affected_cpus);
907cpufreq_freq_attr_rw(scaling_min_freq);
908cpufreq_freq_attr_rw(scaling_max_freq);
909cpufreq_freq_attr_rw(scaling_governor);
910cpufreq_freq_attr_rw(scaling_setspeed);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911
Dave Jones905d77c2008-03-05 14:28:32 -0500912static struct attribute *default_attrs[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913 &cpuinfo_min_freq.attr,
914 &cpuinfo_max_freq.attr,
Thomas Renningered129782009-02-04 01:17:41 +0100915 &cpuinfo_transition_latency.attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916 &scaling_min_freq.attr,
917 &scaling_max_freq.attr,
918 &affected_cpus.attr,
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700919 &related_cpus.attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 &scaling_governor.attr,
921 &scaling_driver.attr,
922 &scaling_available_governors.attr,
Venki Pallipadi9e769882007-10-26 10:18:21 -0700923 &scaling_setspeed.attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 NULL
925};
926
Dave Jones29464f22009-01-18 01:37:11 -0500927#define to_policy(k) container_of(k, struct cpufreq_policy, kobj)
928#define to_attr(a) container_of(a, struct freq_attr, attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929
Dave Jones29464f22009-01-18 01:37:11 -0500930static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931{
Dave Jones905d77c2008-03-05 14:28:32 -0500932 struct cpufreq_policy *policy = to_policy(kobj);
933 struct freq_attr *fattr = to_attr(attr);
Viresh Kumar1b750e32013-10-02 14:13:09 +0530934 ssize_t ret;
Viresh Kumar6eed9402013-08-06 22:53:11 +0530935
viresh kumarad7722d2013-10-18 19:10:15 +0530936 down_read(&policy->rwsem);
Rafael J. Wysocki6541aef2016-02-12 23:56:21 +0100937 ret = fattr->show(policy, buf);
viresh kumarad7722d2013-10-18 19:10:15 +0530938 up_read(&policy->rwsem);
Viresh Kumar1b750e32013-10-02 14:13:09 +0530939
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940 return ret;
941}
942
Dave Jones905d77c2008-03-05 14:28:32 -0500943static ssize_t store(struct kobject *kobj, struct attribute *attr,
944 const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945{
Dave Jones905d77c2008-03-05 14:28:32 -0500946 struct cpufreq_policy *policy = to_policy(kobj);
947 struct freq_attr *fattr = to_attr(attr);
Dave Jonesa07530b2008-03-05 14:22:25 -0500948 ssize_t ret = -EINVAL;
Viresh Kumar6eed9402013-08-06 22:53:11 +0530949
Waiman Long9b3d9bb2018-07-24 14:26:05 -0400950 /*
951 * cpus_read_trylock() is used here to work around a circular lock
952 * dependency problem with respect to the cpufreq_register_driver().
953 */
954 if (!cpus_read_trylock())
955 return -EBUSY;
Srivatsa S. Bhat4f750c92013-09-07 01:23:43 +0530956
Rafael J. Wysocki6541aef2016-02-12 23:56:21 +0100957 if (cpu_online(policy->cpu)) {
958 down_write(&policy->rwsem);
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530959 ret = fattr->store(policy, buf, count);
Rafael J. Wysocki6541aef2016-02-12 23:56:21 +0100960 up_write(&policy->rwsem);
961 }
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530962
Sebastian Andrzej Siewiora92551e2017-05-24 10:15:20 +0200963 cpus_read_unlock();
Srivatsa S. Bhat4f750c92013-09-07 01:23:43 +0530964
Linus Torvalds1da177e2005-04-16 15:20:36 -0700965 return ret;
966}
967
Dave Jones905d77c2008-03-05 14:28:32 -0500968static void cpufreq_sysfs_release(struct kobject *kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969{
Dave Jones905d77c2008-03-05 14:28:32 -0500970 struct cpufreq_policy *policy = to_policy(kobj);
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200971 pr_debug("last reference is dropped\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972 complete(&policy->kobj_unregister);
973}
974
Emese Revfy52cf25d2010-01-19 02:58:23 +0100975static const struct sysfs_ops sysfs_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976 .show = show,
977 .store = store,
978};
979
980static struct kobj_type ktype_cpufreq = {
981 .sysfs_ops = &sysfs_ops,
982 .default_attrs = default_attrs,
983 .release = cpufreq_sysfs_release,
984};
985
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +0200986static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu)
Viresh Kumar87549142015-06-10 02:13:21 +0200987{
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +0200988 struct device *dev = get_cpu_device(cpu);
989
Viresh Kumar67d874c2019-07-08 16:27:52 +0530990 if (unlikely(!dev))
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +0200991 return;
992
993 if (cpumask_test_and_set_cpu(cpu, policy->real_cpus))
994 return;
995
Viresh Kumar266198042016-09-12 12:07:05 +0530996 dev_dbg(dev, "%s: Adding symlink\n", __func__);
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +0200997 if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"))
998 dev_err(dev, "cpufreq symlink creation failed\n");
Viresh Kumar87549142015-06-10 02:13:21 +0200999}
1000
Viresh Kumar266198042016-09-12 12:07:05 +05301001static void remove_cpu_dev_symlink(struct cpufreq_policy *policy,
1002 struct device *dev)
Viresh Kumar87549142015-06-10 02:13:21 +02001003{
Viresh Kumar266198042016-09-12 12:07:05 +05301004 dev_dbg(dev, "%s: Removing symlink\n", __func__);
1005 sysfs_remove_link(&dev->kobj, "cpufreq");
Viresh Kumar87549142015-06-10 02:13:21 +02001006}
1007
Rafael J. Wysockid9612a42015-07-27 23:11:37 +02001008static int cpufreq_add_dev_interface(struct cpufreq_policy *policy)
Dave Jones909a6942009-07-08 18:05:42 -04001009{
1010 struct freq_attr **drv_attr;
Dave Jones909a6942009-07-08 18:05:42 -04001011 int ret = 0;
Dave Jones909a6942009-07-08 18:05:42 -04001012
Dave Jones909a6942009-07-08 18:05:42 -04001013 /* set up files for this cpu device */
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001014 drv_attr = cpufreq_driver->attr;
Viresh Kumarf13f1182015-01-02 12:34:23 +05301015 while (drv_attr && *drv_attr) {
Dave Jones909a6942009-07-08 18:05:42 -04001016 ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
1017 if (ret)
Tomeu Vizoso6d4e81e2014-11-24 10:08:03 +01001018 return ret;
Dave Jones909a6942009-07-08 18:05:42 -04001019 drv_attr++;
1020 }
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001021 if (cpufreq_driver->get) {
Dave Jones909a6942009-07-08 18:05:42 -04001022 ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr);
1023 if (ret)
Tomeu Vizoso6d4e81e2014-11-24 10:08:03 +01001024 return ret;
Dave Jones909a6942009-07-08 18:05:42 -04001025 }
Dirk Brandewiec034b022014-10-13 08:37:40 -07001026
1027 ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
1028 if (ret)
Tomeu Vizoso6d4e81e2014-11-24 10:08:03 +01001029 return ret;
Dirk Brandewiec034b022014-10-13 08:37:40 -07001030
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001031 if (cpufreq_driver->bios_limit) {
Thomas Renningere2f74f32009-11-19 12:31:01 +01001032 ret = sysfs_create_file(&policy->kobj, &bios_limit.attr);
1033 if (ret)
Tomeu Vizoso6d4e81e2014-11-24 10:08:03 +01001034 return ret;
Thomas Renningere2f74f32009-11-19 12:31:01 +01001035 }
Dave Jones909a6942009-07-08 18:05:42 -04001036
Viresh Kumar266198042016-09-12 12:07:05 +05301037 return 0;
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +05301038}
1039
Rafael J. Wysockide1df262016-02-05 02:37:42 +01001040__weak struct cpufreq_governor *cpufreq_default_governor(void)
1041{
1042 return NULL;
1043}
1044
Viresh Kumar7f0fa402015-07-08 15:12:16 +05301045static int cpufreq_init_policy(struct cpufreq_policy *policy)
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +05301046{
Yue Huab05d972019-04-29 15:24:18 +08001047 struct cpufreq_governor *gov = NULL, *def_gov = NULL;
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +05301048 struct cpufreq_policy new_policy;
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +05301049
Viresh Kumard5b73cd2013-08-06 22:53:06 +05301050 memcpy(&new_policy, policy, sizeof(*policy));
Jason Barona27a9ab2013-12-19 22:50:50 +00001051
Yue Huab05d972019-04-29 15:24:18 +08001052 def_gov = cpufreq_default_governor();
1053
1054 if (has_target()) {
1055 /*
1056 * Update governor of new_policy to the governor used before
1057 * hotplug
1058 */
1059 gov = find_governor(policy->last_governor);
1060 if (gov) {
1061 pr_debug("Restoring governor %s for cpu %d\n",
viresh kumar6e2c89d2014-03-04 11:43:59 +08001062 policy->governor->name, policy->cpu);
Yue Huab05d972019-04-29 15:24:18 +08001063 } else {
1064 if (!def_gov)
1065 return -ENODATA;
1066 gov = def_gov;
1067 }
1068 new_policy.governor = gov;
Rafael J. Wysockide1df262016-02-05 02:37:42 +01001069 } else {
Yue Huab05d972019-04-29 15:24:18 +08001070 /* Use the default policy if there is no last_policy. */
1071 if (policy->last_policy) {
Srinivas Pandruvada69030dd12015-12-01 16:52:14 -08001072 new_policy.policy = policy->last_policy;
Yue Huab05d972019-04-29 15:24:18 +08001073 } else {
1074 if (!def_gov)
1075 return -ENODATA;
1076 cpufreq_parse_policy(def_gov->name, &new_policy);
1077 }
Srinivas Pandruvada69030dd12015-12-01 16:52:14 -08001078 }
Yue Huab05d972019-04-29 15:24:18 +08001079
Viresh Kumar7f0fa402015-07-08 15:12:16 +05301080 return cpufreq_set_policy(policy, &new_policy);
Dave Jones909a6942009-07-08 18:05:42 -04001081}
1082
Rafael J. Wysockid9612a42015-07-27 23:11:37 +02001083static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu)
Viresh Kumarfcf80582013-01-29 14:39:08 +00001084{
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301085 int ret = 0;
Viresh Kumarfcf80582013-01-29 14:39:08 +00001086
Viresh Kumarbb29ae12015-02-19 17:02:06 +05301087 /* Has this CPU been taken care of already? */
1088 if (cpumask_test_cpu(cpu, policy->cpus))
1089 return 0;
1090
Viresh Kumar49f18562016-02-11 17:31:12 +05301091 down_write(&policy->rwsem);
Rafael J. Wysocki45482c72016-05-12 15:14:12 +02001092 if (has_target())
1093 cpufreq_stop_governor(policy);
Viresh Kumarfcf80582013-01-29 14:39:08 +00001094
Viresh Kumarfcf80582013-01-29 14:39:08 +00001095 cpumask_set_cpu(cpu, policy->cpus);
Viresh Kumar2eaa3e22013-02-07 10:55:00 +05301096
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301097 if (has_target()) {
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01001098 ret = cpufreq_start_governor(policy);
Viresh Kumar49f18562016-02-11 17:31:12 +05301099 if (ret)
Viresh Kumar3de9bde2013-08-06 22:53:13 +05301100 pr_err("%s: Failed to start governor\n", __func__);
Viresh Kumar820c6ca2013-04-22 00:48:03 +02001101 }
Viresh Kumar49f18562016-02-11 17:31:12 +05301102 up_write(&policy->rwsem);
1103 return ret;
Viresh Kumarfcf80582013-01-29 14:39:08 +00001104}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105
Viresh Kumarc57b25b2019-07-04 13:06:22 +05301106void refresh_frequency_limits(struct cpufreq_policy *policy)
Viresh Kumar70a59fd2019-06-20 08:35:50 +05301107{
Viresh Kumar67d874c2019-07-08 16:27:52 +05301108 struct cpufreq_policy new_policy;
Viresh Kumar70a59fd2019-06-20 08:35:50 +05301109
Viresh Kumar67d874c2019-07-08 16:27:52 +05301110 if (!policy_is_inactive(policy)) {
1111 new_policy = *policy;
1112 pr_debug("updating policy for CPU %u\n", policy->cpu);
Viresh Kumar70a59fd2019-06-20 08:35:50 +05301113
Viresh Kumar67d874c2019-07-08 16:27:52 +05301114 cpufreq_set_policy(policy, &new_policy);
1115 }
Viresh Kumar70a59fd2019-06-20 08:35:50 +05301116}
Viresh Kumarc57b25b2019-07-04 13:06:22 +05301117EXPORT_SYMBOL(refresh_frequency_limits);
Viresh Kumar70a59fd2019-06-20 08:35:50 +05301118
Viresh Kumar11eb69b2016-02-22 16:36:42 +05301119static void handle_update(struct work_struct *work)
1120{
1121 struct cpufreq_policy *policy =
1122 container_of(work, struct cpufreq_policy, update);
Viresh Kumar70a59fd2019-06-20 08:35:50 +05301123
1124 pr_debug("handle_update for cpu %u called\n", policy->cpu);
Viresh Kumar67d874c2019-07-08 16:27:52 +05301125 down_write(&policy->rwsem);
Viresh Kumar70a59fd2019-06-20 08:35:50 +05301126 refresh_frequency_limits(policy);
Viresh Kumar67d874c2019-07-08 16:27:52 +05301127 up_write(&policy->rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128}
1129
Viresh Kumar67d874c2019-07-08 16:27:52 +05301130static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq,
1131 void *data)
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301132{
Viresh Kumar67d874c2019-07-08 16:27:52 +05301133 struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min);
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301134
Viresh Kumar67d874c2019-07-08 16:27:52 +05301135 schedule_work(&policy->update);
1136 return 0;
1137}
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301138
Viresh Kumar67d874c2019-07-08 16:27:52 +05301139static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq,
1140 void *data)
1141{
1142 struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max);
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301143
Viresh Kumar67d874c2019-07-08 16:27:52 +05301144 schedule_work(&policy->update);
1145 return 0;
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301146}
1147
Viresh Kumarf9f41e3e2017-01-05 10:17:27 +05301148static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy)
Viresh Kumar42f921a2013-12-20 21:26:02 +05301149{
1150 struct kobject *kobj;
1151 struct completion *cmp;
1152
Viresh Kumar87549142015-06-10 02:13:21 +02001153 down_write(&policy->rwsem);
Rafael J. Wysocki1aefc752016-05-31 22:14:44 +02001154 cpufreq_stats_free_table(policy);
Viresh Kumar42f921a2013-12-20 21:26:02 +05301155 kobj = &policy->kobj;
1156 cmp = &policy->kobj_unregister;
Viresh Kumar87549142015-06-10 02:13:21 +02001157 up_write(&policy->rwsem);
Viresh Kumar42f921a2013-12-20 21:26:02 +05301158 kobject_put(kobj);
1159
1160 /*
1161 * We need to make sure that the underlying kobj is
1162 * actually not referenced anymore by anybody before we
1163 * proceed with unloading.
1164 */
1165 pr_debug("waiting for dropping of refcount\n");
1166 wait_for_completion(cmp);
1167 pr_debug("wait complete\n");
1168}
1169
Viresh Kumar67d874c2019-07-08 16:27:52 +05301170static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
1171{
1172 struct cpufreq_policy *policy;
1173 struct device *dev = get_cpu_device(cpu);
1174 int ret;
1175
1176 if (!dev)
1177 return NULL;
1178
1179 policy = kzalloc(sizeof(*policy), GFP_KERNEL);
1180 if (!policy)
1181 return NULL;
1182
1183 if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL))
1184 goto err_free_policy;
1185
1186 if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL))
1187 goto err_free_cpumask;
1188
1189 if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL))
1190 goto err_free_rcpumask;
1191
1192 ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq,
1193 cpufreq_global_kobject, "policy%u", cpu);
1194 if (ret) {
1195 dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret);
1196 /*
1197 * The entire policy object will be freed below, but the extra
1198 * memory allocated for the kobject name needs to be freed by
1199 * releasing the kobject.
1200 */
1201 kobject_put(&policy->kobj);
1202 goto err_free_real_cpus;
1203 }
1204
1205 policy->nb_min.notifier_call = cpufreq_notifier_min;
1206 policy->nb_max.notifier_call = cpufreq_notifier_max;
1207
1208 ret = dev_pm_qos_add_notifier(dev, &policy->nb_min,
1209 DEV_PM_QOS_MIN_FREQUENCY);
1210 if (ret) {
1211 dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n",
1212 ret, cpumask_pr_args(policy->cpus));
1213 goto err_kobj_remove;
1214 }
1215
1216 ret = dev_pm_qos_add_notifier(dev, &policy->nb_max,
1217 DEV_PM_QOS_MAX_FREQUENCY);
1218 if (ret) {
1219 dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n",
1220 ret, cpumask_pr_args(policy->cpus));
1221 goto err_min_qos_notifier;
1222 }
1223
1224 INIT_LIST_HEAD(&policy->policy_list);
1225 init_rwsem(&policy->rwsem);
1226 spin_lock_init(&policy->transition_lock);
1227 init_waitqueue_head(&policy->transition_wait);
1228 init_completion(&policy->kobj_unregister);
1229 INIT_WORK(&policy->update, handle_update);
1230
1231 policy->cpu = cpu;
1232 return policy;
1233
1234err_min_qos_notifier:
1235 dev_pm_qos_remove_notifier(dev, &policy->nb_min,
1236 DEV_PM_QOS_MIN_FREQUENCY);
1237err_kobj_remove:
1238 cpufreq_policy_put_kobj(policy);
1239err_free_real_cpus:
1240 free_cpumask_var(policy->real_cpus);
1241err_free_rcpumask:
1242 free_cpumask_var(policy->related_cpus);
1243err_free_cpumask:
1244 free_cpumask_var(policy->cpus);
1245err_free_policy:
1246 kfree(policy);
1247
1248 return NULL;
1249}
1250
Viresh Kumarf9f41e3e2017-01-05 10:17:27 +05301251static void cpufreq_policy_free(struct cpufreq_policy *policy)
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301252{
Viresh Kumar67d874c2019-07-08 16:27:52 +05301253 struct device *dev = get_cpu_device(policy->cpu);
Viresh Kumar988bed02015-05-08 11:53:45 +05301254 unsigned long flags;
1255 int cpu;
1256
1257 /* Remove policy from list */
1258 write_lock_irqsave(&cpufreq_driver_lock, flags);
1259 list_del(&policy->policy_list);
1260
1261 for_each_cpu(cpu, policy->related_cpus)
1262 per_cpu(cpufreq_cpu_data, cpu) = NULL;
1263 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
1264
Viresh Kumar67d874c2019-07-08 16:27:52 +05301265 dev_pm_qos_remove_notifier(dev, &policy->nb_max,
1266 DEV_PM_QOS_MAX_FREQUENCY);
1267 dev_pm_qos_remove_notifier(dev, &policy->nb_min,
1268 DEV_PM_QOS_MIN_FREQUENCY);
Viresh Kumar18c49922019-07-05 16:21:24 +05301269 dev_pm_qos_remove_request(policy->max_freq_req);
1270 dev_pm_qos_remove_request(policy->min_freq_req);
1271 kfree(policy->min_freq_req);
Viresh Kumar67d874c2019-07-08 16:27:52 +05301272
Viresh Kumarf9f41e3e2017-01-05 10:17:27 +05301273 cpufreq_policy_put_kobj(policy);
Rafael J. Wysocki559ed402015-07-26 02:07:47 +02001274 free_cpumask_var(policy->real_cpus);
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301275 free_cpumask_var(policy->related_cpus);
1276 free_cpumask_var(policy->cpus);
1277 kfree(policy);
1278}
1279
Rafael J. Wysocki0b275352015-07-29 03:03:44 +02001280static int cpufreq_online(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281{
Viresh Kumar7f0c0202015-01-02 12:34:32 +05301282 struct cpufreq_policy *policy;
Rafael J. Wysocki194d99c2015-07-29 03:08:57 +02001283 bool new_policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001284 unsigned long flags;
Rafael J. Wysocki0b275352015-07-29 03:03:44 +02001285 unsigned int j;
1286 int ret;
Ashok Rajc32b6b82005-10-30 14:59:54 -08001287
Rafael J. Wysocki0b275352015-07-29 03:03:44 +02001288 pr_debug("%s: bringing CPU%u online\n", __func__, cpu);
Viresh Kumar6eed9402013-08-06 22:53:11 +05301289
Viresh Kumarbb29ae12015-02-19 17:02:06 +05301290 /* Check if this CPU already has a policy to manage it */
Viresh Kumar9104bb22015-05-12 12:22:12 +05301291 policy = per_cpu(cpufreq_cpu_data, cpu);
Rafael J. Wysocki11ce7072015-07-27 23:11:21 +02001292 if (policy) {
Viresh Kumar9104bb22015-05-12 12:22:12 +05301293 WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus));
Rafael J. Wysocki11ce7072015-07-27 23:11:21 +02001294 if (!policy_is_inactive(policy))
Rafael J. Wysockid9612a42015-07-27 23:11:37 +02001295 return cpufreq_add_policy_cpu(policy, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296
Rafael J. Wysocki11ce7072015-07-27 23:11:21 +02001297 /* This is the only online CPU for the policy. Start over. */
Rafael J. Wysocki194d99c2015-07-29 03:08:57 +02001298 new_policy = false;
Rafael J. Wysocki11ce7072015-07-27 23:11:21 +02001299 down_write(&policy->rwsem);
1300 policy->cpu = cpu;
1301 policy->governor = NULL;
1302 up_write(&policy->rwsem);
1303 } else {
Rafael J. Wysocki194d99c2015-07-29 03:08:57 +02001304 new_policy = true;
Rafael J. Wysockia34e63b2015-07-27 23:11:50 +02001305 policy = cpufreq_policy_alloc(cpu);
Rafael J. Wysocki72368d12013-12-27 01:07:11 +01001306 if (!policy)
Rafael J. Wysockid4d854d2015-07-27 23:11:30 +02001307 return -ENOMEM;
Rafael J. Wysocki72368d12013-12-27 01:07:11 +01001308 }
Srivatsa S. Bhat0d66b912013-09-12 01:42:59 +05301309
Viresh Kumar91a12e92019-02-12 16:36:04 +05301310 if (!new_policy && cpufreq_driver->online) {
1311 ret = cpufreq_driver->online(policy);
1312 if (ret) {
1313 pr_debug("%s: %d: initialization failed\n", __func__,
1314 __LINE__);
1315 goto out_exit_policy;
1316 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001317
Viresh Kumar91a12e92019-02-12 16:36:04 +05301318 /* Recover policy->cpus using related_cpus */
1319 cpumask_copy(policy->cpus, policy->related_cpus);
1320 } else {
1321 cpumask_copy(policy->cpus, cpumask_of(cpu));
Viresh Kumar643ae6e2013-01-12 05:14:38 +00001322
Viresh Kumar91a12e92019-02-12 16:36:04 +05301323 /*
1324 * Call driver. From then on the cpufreq must be able
1325 * to accept all calls to ->verify and ->setpolicy for this CPU.
1326 */
1327 ret = cpufreq_driver->init(policy);
1328 if (ret) {
1329 pr_debug("%s: %d: initialization failed\n", __func__,
1330 __LINE__);
1331 goto out_free_policy;
1332 }
Viresh Kumard417e062018-02-22 11:29:44 +05301333
Viresh Kumar91a12e92019-02-12 16:36:04 +05301334 ret = cpufreq_table_validate_and_sort(policy);
1335 if (ret)
1336 goto out_exit_policy;
Tomeu Vizoso6d4e81e2014-11-24 10:08:03 +01001337
Rafael J. Wysocki4d1f3a52015-07-27 23:11:44 +02001338 /* related_cpus should at least include policy->cpus. */
Viresh Kumar0998a032015-10-15 21:35:21 +05301339 cpumask_copy(policy->related_cpus, policy->cpus);
Rafael J. Wysocki4d1f3a52015-07-27 23:11:44 +02001340 }
Rafael J. Wysocki559ed402015-07-26 02:07:47 +02001341
Viresh Kumar91a12e92019-02-12 16:36:04 +05301342 down_write(&policy->rwsem);
Viresh Kumar5a7e56a2014-03-04 11:44:00 +08001343 /*
1344 * affected cpus must always be the one, which are online. We aren't
1345 * managing offline cpus here.
1346 */
1347 cpumask_and(policy->cpus, policy->cpus, cpu_online_mask);
1348
Rafael J. Wysocki194d99c2015-07-29 03:08:57 +02001349 if (new_policy) {
Viresh Kumar18c49922019-07-05 16:21:24 +05301350 struct device *dev = get_cpu_device(cpu);
Tomeu Vizoso6d4e81e2014-11-24 10:08:03 +01001351
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +02001352 for_each_cpu(j, policy->related_cpus) {
Viresh Kumar988bed02015-05-08 11:53:45 +05301353 per_cpu(cpufreq_cpu_data, j) = policy;
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +02001354 add_cpu_dev_symlink(policy, j);
1355 }
Viresh Kumar18c49922019-07-05 16:21:24 +05301356
1357 policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req),
1358 GFP_KERNEL);
1359 if (!policy->min_freq_req)
1360 goto out_destroy_policy;
1361
1362 ret = dev_pm_qos_add_request(dev, policy->min_freq_req,
1363 DEV_PM_QOS_MIN_FREQUENCY,
1364 policy->min);
1365 if (ret < 0) {
1366 /*
1367 * So we don't call dev_pm_qos_remove_request() for an
1368 * uninitialized request.
1369 */
1370 kfree(policy->min_freq_req);
1371 policy->min_freq_req = NULL;
1372
1373 dev_err(dev, "Failed to add min-freq constraint (%d)\n",
1374 ret);
1375 goto out_destroy_policy;
1376 }
1377
1378 /*
1379 * This must be initialized right here to avoid calling
1380 * dev_pm_qos_remove_request() on uninitialized request in case
1381 * of errors.
1382 */
1383 policy->max_freq_req = policy->min_freq_req + 1;
1384
1385 ret = dev_pm_qos_add_request(dev, policy->max_freq_req,
1386 DEV_PM_QOS_MAX_FREQUENCY,
1387 policy->max);
1388 if (ret < 0) {
1389 policy->max_freq_req = NULL;
1390 dev_err(dev, "Failed to add max-freq constraint (%d)\n",
1391 ret);
1392 goto out_destroy_policy;
1393 }
Viresh Kumar988bed02015-05-08 11:53:45 +05301394 }
Viresh Kumar652ed952014-01-09 20:38:43 +05301395
Viresh Kumar5ddc6d42019-06-20 08:35:48 +05301396 if (cpufreq_driver->get && has_target()) {
Viresh Kumarda60ce92013-10-03 20:28:30 +05301397 policy->cur = cpufreq_driver->get(policy->cpu);
1398 if (!policy->cur) {
1399 pr_err("%s: ->get() failed\n", __func__);
Viresh Kumard417e062018-02-22 11:29:44 +05301400 goto out_destroy_policy;
Viresh Kumarda60ce92013-10-03 20:28:30 +05301401 }
1402 }
1403
Viresh Kumard3916692013-12-03 11:20:46 +05301404 /*
1405 * Sometimes boot loaders set CPU frequency to a value outside of
1406 * frequency table present with cpufreq core. In such cases CPU might be
1407 * unstable if it has to run on that frequency for long duration of time
1408 * and so its better to set it to a frequency which is specified in
1409 * freq-table. This also makes cpufreq stats inconsistent as
1410 * cpufreq-stats would fail to register because current frequency of CPU
1411 * isn't found in freq-table.
1412 *
1413 * Because we don't want this change to effect boot process badly, we go
1414 * for the next freq which is >= policy->cur ('cur' must be set by now,
1415 * otherwise we will end up setting freq to lowest of the table as 'cur'
1416 * is initialized to zero).
1417 *
1418 * We are passing target-freq as "policy->cur - 1" otherwise
1419 * __cpufreq_driver_target() would simply fail, as policy->cur will be
1420 * equal to target-freq.
1421 */
1422 if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK)
1423 && has_target()) {
1424 /* Are we running at unknown frequency ? */
1425 ret = cpufreq_frequency_table_get_index(policy, policy->cur);
1426 if (ret == -EINVAL) {
1427 /* Warn user and fix it */
1428 pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n",
1429 __func__, policy->cpu, policy->cur);
1430 ret = __cpufreq_driver_target(policy, policy->cur - 1,
1431 CPUFREQ_RELATION_L);
1432
1433 /*
1434 * Reaching here after boot in a few seconds may not
1435 * mean that system will remain stable at "unknown"
1436 * frequency for longer duration. Hence, a BUG_ON().
1437 */
1438 BUG_ON(ret);
1439 pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n",
1440 __func__, policy->cpu, policy->cur);
1441 }
1442 }
1443
Rafael J. Wysocki194d99c2015-07-29 03:08:57 +02001444 if (new_policy) {
Rafael J. Wysockid9612a42015-07-27 23:11:37 +02001445 ret = cpufreq_add_dev_interface(policy);
Srivatsa S. Bhata82fab22013-07-30 04:24:49 +05301446 if (ret)
Viresh Kumard417e062018-02-22 11:29:44 +05301447 goto out_destroy_policy;
Rafael J. Wysocki1aefc752016-05-31 22:14:44 +02001448
1449 cpufreq_stats_create_table(policy);
Dave Jones8ff69732006-03-05 03:37:23 -05001450
Viresh Kumar988bed02015-05-08 11:53:45 +05301451 write_lock_irqsave(&cpufreq_driver_lock, flags);
1452 list_add(&policy->policy_list, &cpufreq_policy_list);
1453 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
1454 }
Viresh Kumar9515f4d2013-08-20 12:08:23 +05301455
Viresh Kumar7f0fa402015-07-08 15:12:16 +05301456 ret = cpufreq_init_policy(policy);
1457 if (ret) {
1458 pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n",
1459 __func__, cpu, ret);
Viresh Kumard417e062018-02-22 11:29:44 +05301460 goto out_destroy_policy;
Viresh Kumar08fd8c1c2013-12-24 07:11:01 +05301461 }
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +05301462
Viresh Kumar4e97b632014-03-04 11:44:01 +08001463 up_write(&policy->rwsem);
Viresh Kumar08fd8c1c2013-12-24 07:11:01 +05301464
Greg Kroah-Hartman038c5b32007-12-17 15:54:39 -04001465 kobject_uevent(&policy->kobj, KOBJ_ADD);
Viresh Kumar7c45cf32014-11-27 06:07:51 +05301466
Viresh Kumar7c45cf32014-11-27 06:07:51 +05301467 /* Callback for handling stuff after policy is ready */
1468 if (cpufreq_driver->ready)
1469 cpufreq_driver->ready(policy);
1470
Daniel Lezcanobcc61562019-06-25 13:32:41 +02001471 if (cpufreq_thermal_control_enabled(cpufreq_driver))
Amit Kucheria5c238a82019-01-30 10:52:01 +05301472 policy->cdev = of_cpufreq_cooling_register(policy);
1473
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02001474 pr_debug("initialization complete\n");
Dave Jones87c32272006-03-29 01:48:37 -05001475
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476 return 0;
1477
Viresh Kumard417e062018-02-22 11:29:44 +05301478out_destroy_policy:
Viresh Kumarb24b6472018-02-22 11:29:43 +05301479 for_each_cpu(j, policy->real_cpus)
1480 remove_cpu_dev_symlink(policy, get_cpu_device(j));
1481
Prarit Bhargava7106e022014-09-10 10:12:08 -04001482 up_write(&policy->rwsem);
1483
Viresh Kumard417e062018-02-22 11:29:44 +05301484out_exit_policy:
Viresh Kumarda60ce92013-10-03 20:28:30 +05301485 if (cpufreq_driver->exit)
1486 cpufreq_driver->exit(policy);
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +02001487
Viresh Kumar8101f992015-07-08 15:12:15 +05301488out_free_policy:
Viresh Kumarf9f41e3e2017-01-05 10:17:27 +05301489 cpufreq_policy_free(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001490 return ret;
1491}
1492
Rafael J. Wysocki0b275352015-07-29 03:03:44 +02001493/**
1494 * cpufreq_add_dev - the cpufreq interface for a CPU device.
1495 * @dev: CPU device.
1496 * @sif: Subsystem interface structure pointer (not used)
1497 */
1498static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
1499{
Rafael J. Wysockia794d612016-04-07 03:31:57 +02001500 struct cpufreq_policy *policy;
Rafael J. Wysocki0b275352015-07-29 03:03:44 +02001501 unsigned cpu = dev->id;
Viresh Kumar266198042016-09-12 12:07:05 +05301502 int ret;
Rafael J. Wysocki0b275352015-07-29 03:03:44 +02001503
1504 dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu);
1505
Viresh Kumar266198042016-09-12 12:07:05 +05301506 if (cpu_online(cpu)) {
1507 ret = cpufreq_online(cpu);
1508 if (ret)
1509 return ret;
1510 }
Rafael J. Wysocki0b275352015-07-29 03:03:44 +02001511
Viresh Kumar266198042016-09-12 12:07:05 +05301512 /* Create sysfs link on CPU registration */
Rafael J. Wysockia794d612016-04-07 03:31:57 +02001513 policy = per_cpu(cpufreq_cpu_data, cpu);
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +02001514 if (policy)
1515 add_cpu_dev_symlink(policy, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001516
Rafael J. Wysocki2f0ba792017-03-27 19:33:09 +02001517 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518}
1519
Sebastian Andrzej Siewior27622b02016-09-06 19:04:48 +02001520static int cpufreq_offline(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001521{
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301522 struct cpufreq_policy *policy;
Viresh Kumar69cee712016-02-11 17:31:11 +05301523 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001524
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001525 pr_debug("%s: unregistering CPU %u\n", __func__, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001526
Viresh Kumar988bed02015-05-08 11:53:45 +05301527 policy = cpufreq_cpu_get_raw(cpu);
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301528 if (!policy) {
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001529 pr_debug("%s: No cpu_data found\n", __func__);
Sebastian Andrzej Siewior27622b02016-09-06 19:04:48 +02001530 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001531 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001532
Viresh Kumar49f18562016-02-11 17:31:12 +05301533 down_write(&policy->rwsem);
Rafael J. Wysocki45482c72016-05-12 15:14:12 +02001534 if (has_target())
1535 cpufreq_stop_governor(policy);
Jacob Shin27ecddc2011-04-27 13:32:11 -05001536
Viresh Kumar9591bec2015-06-10 02:20:23 +02001537 cpumask_clear_cpu(cpu, policy->cpus);
Viresh Kumar45732372015-05-12 12:22:34 +05301538
Viresh Kumar9591bec2015-06-10 02:20:23 +02001539 if (policy_is_inactive(policy)) {
1540 if (has_target())
1541 strncpy(policy->last_governor, policy->governor->name,
1542 CPUFREQ_NAME_LEN);
Srinivas Pandruvada69030dd12015-12-01 16:52:14 -08001543 else
1544 policy->last_policy = policy->policy;
Viresh Kumar9591bec2015-06-10 02:20:23 +02001545 } else if (cpu == policy->cpu) {
1546 /* Nominate new CPU */
1547 policy->cpu = cpumask_any(policy->cpus);
1548 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549
Viresh Kumar9591bec2015-06-10 02:20:23 +02001550 /* Start governor again for active policy */
1551 if (!policy_is_inactive(policy)) {
1552 if (has_target()) {
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01001553 ret = cpufreq_start_governor(policy);
Viresh Kumar9591bec2015-06-10 02:20:23 +02001554 if (ret)
1555 pr_err("%s: Failed to start governor\n", __func__);
1556 }
Viresh Kumar69cee712016-02-11 17:31:11 +05301557
Viresh Kumar49f18562016-02-11 17:31:12 +05301558 goto unlock;
Viresh Kumar69cee712016-02-11 17:31:11 +05301559 }
1560
Daniel Lezcanobcc61562019-06-25 13:32:41 +02001561 if (cpufreq_thermal_control_enabled(cpufreq_driver)) {
Amit Kucheria5c238a82019-01-30 10:52:01 +05301562 cpufreq_cooling_unregister(policy->cdev);
1563 policy->cdev = NULL;
1564 }
1565
Viresh Kumar69cee712016-02-11 17:31:11 +05301566 if (cpufreq_driver->stop_cpu)
Dirk Brandewie367dc4a2014-03-19 08:45:53 -07001567 cpufreq_driver->stop_cpu(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001568
Rafael J. Wysocki36be3412016-05-12 15:13:35 +02001569 if (has_target())
1570 cpufreq_exit_governor(policy);
Viresh Kumar87549142015-06-10 02:13:21 +02001571
Viresh Kumar87549142015-06-10 02:13:21 +02001572 /*
Viresh Kumar91a12e92019-02-12 16:36:04 +05301573 * Perform the ->offline() during light-weight tear-down, as
1574 * that allows fast recovery when the CPU comes back.
Viresh Kumar87549142015-06-10 02:13:21 +02001575 */
Viresh Kumar91a12e92019-02-12 16:36:04 +05301576 if (cpufreq_driver->offline) {
1577 cpufreq_driver->offline(policy);
1578 } else if (cpufreq_driver->exit) {
Viresh Kumar87549142015-06-10 02:13:21 +02001579 cpufreq_driver->exit(policy);
Srinivas Pandruvada55582bc2015-10-07 13:50:44 -07001580 policy->freq_table = NULL;
1581 }
Viresh Kumar49f18562016-02-11 17:31:12 +05301582
1583unlock:
1584 up_write(&policy->rwsem);
Sebastian Andrzej Siewior27622b02016-09-06 19:04:48 +02001585 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001586}
1587
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301588/**
Viresh Kumar27a862e2013-10-02 14:13:14 +05301589 * cpufreq_remove_dev - remove a CPU device
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301590 *
1591 * Removes the cpufreq interface for a CPU device.
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301592 */
Viresh Kumar71db87b2015-07-30 15:04:01 +05301593static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001594{
Kay Sievers8a25a2f2011-12-21 14:29:42 -08001595 unsigned int cpu = dev->id;
Rafael J. Wysocki559ed402015-07-26 02:07:47 +02001596 struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
Venki Pallipadiec282972007-03-26 12:03:19 -07001597
Rafael J. Wysocki559ed402015-07-26 02:07:47 +02001598 if (!policy)
Linus Torvalds1af115d2015-08-31 08:47:40 -07001599 return;
Viresh Kumar87549142015-06-10 02:13:21 +02001600
Viresh Kumar69cee712016-02-11 17:31:11 +05301601 if (cpu_online(cpu))
1602 cpufreq_offline(cpu);
Viresh Kumar87549142015-06-10 02:13:21 +02001603
Rafael J. Wysocki559ed402015-07-26 02:07:47 +02001604 cpumask_clear_cpu(cpu, policy->real_cpus);
Viresh Kumar266198042016-09-12 12:07:05 +05301605 remove_cpu_dev_symlink(policy, dev);
Viresh Kumarf344dae2015-11-21 09:06:49 +05301606
Viresh Kumar91a12e92019-02-12 16:36:04 +05301607 if (cpumask_empty(policy->real_cpus)) {
1608 /* We did light-weight exit earlier, do full tear down now */
1609 if (cpufreq_driver->offline)
1610 cpufreq_driver->exit(policy);
1611
Viresh Kumarf9f41e3e2017-01-05 10:17:27 +05301612 cpufreq_policy_free(policy);
Viresh Kumar91a12e92019-02-12 16:36:04 +05301613 }
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001614}
1615
Linus Torvalds1da177e2005-04-16 15:20:36 -07001616/**
Viresh Kumarbb176f72013-06-19 14:19:33 +05301617 * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're
1618 * in deep trouble.
Viresh Kumara1e1dc42015-01-02 12:34:28 +05301619 * @policy: policy managing CPUs
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620 * @new_freq: CPU frequency the CPU actually runs at
1621 *
Dave Jones29464f22009-01-18 01:37:11 -05001622 * We adjust to current frequency first, and need to clean up later.
1623 * So either call to cpufreq_update_policy() or schedule handle_update()).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001624 */
Viresh Kumara1e1dc42015-01-02 12:34:28 +05301625static void cpufreq_out_of_sync(struct cpufreq_policy *policy,
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301626 unsigned int new_freq)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001627{
1628 struct cpufreq_freqs freqs;
Viresh Kumarb43a7ff2013-03-24 11:56:43 +05301629
Joe Perchese837f9b2014-03-11 10:03:00 -07001630 pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n",
Viresh Kumara1e1dc42015-01-02 12:34:28 +05301631 policy->cur, new_freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001632
Viresh Kumara1e1dc42015-01-02 12:34:28 +05301633 freqs.old = policy->cur;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001634 freqs.new = new_freq;
Viresh Kumarb43a7ff2013-03-24 11:56:43 +05301635
Viresh Kumar8fec0512014-03-24 13:35:45 +05301636 cpufreq_freq_transition_begin(policy, &freqs);
1637 cpufreq_freq_transition_end(policy, &freqs, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638}
1639
Viresh Kumar59807522019-06-20 08:35:49 +05301640static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update)
1641{
1642 unsigned int new_freq;
1643
1644 new_freq = cpufreq_driver->get(policy->cpu);
1645 if (!new_freq)
1646 return 0;
1647
1648 /*
1649 * If fast frequency switching is used with the given policy, the check
1650 * against policy->cur is pointless, so skip it in that case.
1651 */
1652 if (policy->fast_switch_enabled || !has_target())
1653 return new_freq;
1654
1655 if (policy->cur != new_freq) {
1656 cpufreq_out_of_sync(policy, new_freq);
1657 if (update)
1658 schedule_work(&policy->update);
1659 }
1660
1661 return new_freq;
1662}
1663
Dave Jones32ee8c32006-02-28 00:43:23 -05001664/**
Dhaval Giani4ab70df2006-12-13 14:49:15 +05301665 * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001666 * @cpu: CPU number
1667 *
1668 * This is the last known freq, without actually getting it from the driver.
1669 * Return value will be same as what is shown in scaling_cur_freq in sysfs.
1670 */
1671unsigned int cpufreq_quick_get(unsigned int cpu)
1672{
Dirk Brandewie9e21ba82013-02-06 09:02:08 -08001673 struct cpufreq_policy *policy;
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301674 unsigned int ret_freq = 0;
Richard Cochranc75361c2016-03-11 09:43:07 +01001675 unsigned long flags;
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001676
Richard Cochranc75361c2016-03-11 09:43:07 +01001677 read_lock_irqsave(&cpufreq_driver_lock, flags);
1678
1679 if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) {
1680 ret_freq = cpufreq_driver->get(cpu);
1681 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
1682 return ret_freq;
1683 }
1684
1685 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
Dirk Brandewie9e21ba82013-02-06 09:02:08 -08001686
1687 policy = cpufreq_cpu_get(cpu);
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001688 if (policy) {
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301689 ret_freq = policy->cur;
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001690 cpufreq_cpu_put(policy);
1691 }
1692
Dave Jones4d34a672008-02-07 16:33:49 -05001693 return ret_freq;
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001694}
1695EXPORT_SYMBOL(cpufreq_quick_get);
1696
Jesse Barnes3d737102011-06-28 10:59:12 -07001697/**
1698 * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU
1699 * @cpu: CPU number
1700 *
1701 * Just return the max possible frequency for a given CPU.
1702 */
1703unsigned int cpufreq_quick_get_max(unsigned int cpu)
1704{
1705 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
1706 unsigned int ret_freq = 0;
1707
1708 if (policy) {
1709 ret_freq = policy->max;
1710 cpufreq_cpu_put(policy);
1711 }
1712
1713 return ret_freq;
1714}
1715EXPORT_SYMBOL(cpufreq_quick_get_max);
1716
Viresh Kumard92d50a2015-01-02 12:34:29 +05301717static unsigned int __cpufreq_get(struct cpufreq_policy *policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001718{
Yue Hu4db7c342019-04-19 14:27:58 +08001719 if (unlikely(policy_is_inactive(policy)))
Viresh Kumar59807522019-06-20 08:35:49 +05301720 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001721
Viresh Kumar59807522019-06-20 08:35:49 +05301722 return cpufreq_verify_current_freq(policy, true);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001723}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001724
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001725/**
1726 * cpufreq_get - get the current CPU frequency (in kHz)
1727 * @cpu: CPU number
1728 *
1729 * Get the CPU current (static) CPU frequency
1730 */
1731unsigned int cpufreq_get(unsigned int cpu)
1732{
Aaron Plattner999976e2014-03-04 12:42:15 -08001733 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001734 unsigned int ret_freq = 0;
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001735
Aaron Plattner999976e2014-03-04 12:42:15 -08001736 if (policy) {
1737 down_read(&policy->rwsem);
Yue Hu4db7c342019-04-19 14:27:58 +08001738 if (cpufreq_driver->get)
1739 ret_freq = __cpufreq_get(policy);
Aaron Plattner999976e2014-03-04 12:42:15 -08001740 up_read(&policy->rwsem);
Viresh Kumar26ca8692013-09-20 22:37:31 +05301741
Aaron Plattner999976e2014-03-04 12:42:15 -08001742 cpufreq_cpu_put(policy);
1743 }
Viresh Kumar6eed9402013-08-06 22:53:11 +05301744
Dave Jones4d34a672008-02-07 16:33:49 -05001745 return ret_freq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001746}
1747EXPORT_SYMBOL(cpufreq_get);
1748
Kay Sievers8a25a2f2011-12-21 14:29:42 -08001749static struct subsys_interface cpufreq_interface = {
1750 .name = "cpufreq",
1751 .subsys = &cpu_subsys,
1752 .add_dev = cpufreq_add_dev,
1753 .remove_dev = cpufreq_remove_dev,
Rafael J. Wysockie00e56d2011-03-23 22:16:32 +01001754};
1755
Viresh Kumare28867e2014-03-04 11:00:27 +08001756/*
1757 * In case platform wants some specific frequency to be configured
1758 * during suspend..
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001759 */
Viresh Kumare28867e2014-03-04 11:00:27 +08001760int cpufreq_generic_suspend(struct cpufreq_policy *policy)
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001761{
Viresh Kumare28867e2014-03-04 11:00:27 +08001762 int ret;
Dave Jones4bc5d342009-08-04 14:03:25 -04001763
Viresh Kumare28867e2014-03-04 11:00:27 +08001764 if (!policy->suspend_freq) {
Bartlomiej Zolnierkiewicz201f3712015-09-08 18:41:02 +02001765 pr_debug("%s: suspend_freq not defined\n", __func__);
1766 return 0;
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001767 }
1768
Viresh Kumare28867e2014-03-04 11:00:27 +08001769 pr_debug("%s: Setting suspend-freq: %u\n", __func__,
1770 policy->suspend_freq);
1771
1772 ret = __cpufreq_driver_target(policy, policy->suspend_freq,
1773 CPUFREQ_RELATION_H);
1774 if (ret)
1775 pr_err("%s: unable to set suspend-freq: %u. err: %d\n",
1776 __func__, policy->suspend_freq, ret);
1777
Dave Jonesc9060492008-02-07 16:32:18 -05001778 return ret;
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001779}
Viresh Kumare28867e2014-03-04 11:00:27 +08001780EXPORT_SYMBOL(cpufreq_generic_suspend);
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001781
1782/**
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001783 * cpufreq_suspend() - Suspend CPUFreq governors
Linus Torvalds1da177e2005-04-16 15:20:36 -07001784 *
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001785 * Called during system wide Suspend/Hibernate cycles for suspending governors
1786 * as some platforms can't change frequency after this point in suspend cycle.
1787 * Because some of the devices (like: i2c, regulators, etc) they use for
1788 * changing frequency are suspended quickly after this point.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001789 */
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001790void cpufreq_suspend(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001791{
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301792 struct cpufreq_policy *policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001793
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001794 if (!cpufreq_driver)
Rafael J. Wysockie00e56d2011-03-23 22:16:32 +01001795 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001796
Rafael J. Wysockiba41e1b2016-05-02 02:27:19 +02001797 if (!has_target() && !cpufreq_driver->suspend)
Viresh Kumarb1b12bab2014-09-30 09:33:17 +05301798 goto suspend;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001799
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001800 pr_debug("%s: Suspending Governors\n", __func__);
1801
Viresh Kumarf9637352015-05-12 12:20:11 +05301802 for_each_active_policy(policy) {
Rafael J. Wysockiba41e1b2016-05-02 02:27:19 +02001803 if (has_target()) {
1804 down_write(&policy->rwsem);
Rafael J. Wysocki45482c72016-05-12 15:14:12 +02001805 cpufreq_stop_governor(policy);
Rafael J. Wysockiba41e1b2016-05-02 02:27:19 +02001806 up_write(&policy->rwsem);
Rafael J. Wysockiba41e1b2016-05-02 02:27:19 +02001807 }
1808
1809 if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy))
Florian Fainellie9a7cc12019-08-21 16:16:32 -07001810 pr_err("%s: Failed to suspend driver: %s\n", __func__,
1811 cpufreq_driver->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001812 }
Viresh Kumarb1b12bab2014-09-30 09:33:17 +05301813
1814suspend:
1815 cpufreq_suspended = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001816}
1817
Linus Torvalds1da177e2005-04-16 15:20:36 -07001818/**
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001819 * cpufreq_resume() - Resume CPUFreq governors
Linus Torvalds1da177e2005-04-16 15:20:36 -07001820 *
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001821 * Called during system wide Suspend/Hibernate cycle for resuming governors that
1822 * are suspended with cpufreq_suspend().
Linus Torvalds1da177e2005-04-16 15:20:36 -07001823 */
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001824void cpufreq_resume(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001825{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001826 struct cpufreq_policy *policy;
Viresh Kumar49f18562016-02-11 17:31:12 +05301827 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001828
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001829 if (!cpufreq_driver)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001830 return;
1831
Bo Yan703cbaa2018-01-23 13:57:55 -08001832 if (unlikely(!cpufreq_suspended))
1833 return;
1834
Lan Tianyu8e304442014-09-18 15:03:07 +08001835 cpufreq_suspended = false;
1836
Rafael J. Wysockiba41e1b2016-05-02 02:27:19 +02001837 if (!has_target() && !cpufreq_driver->resume)
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001838 return;
1839
1840 pr_debug("%s: Resuming Governors\n", __func__);
1841
Viresh Kumarf9637352015-05-12 12:20:11 +05301842 for_each_active_policy(policy) {
Viresh Kumar49f18562016-02-11 17:31:12 +05301843 if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) {
Viresh Kumar0c5aa402014-03-24 12:30:29 +05301844 pr_err("%s: Failed to resume driver: %p\n", __func__,
1845 policy);
Rafael J. Wysockiba41e1b2016-05-02 02:27:19 +02001846 } else if (has_target()) {
Viresh Kumar49f18562016-02-11 17:31:12 +05301847 down_write(&policy->rwsem);
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01001848 ret = cpufreq_start_governor(policy);
Viresh Kumar49f18562016-02-11 17:31:12 +05301849 up_write(&policy->rwsem);
1850
1851 if (ret)
1852 pr_err("%s: Failed to start governor for policy: %p\n",
1853 __func__, policy);
1854 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001855 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001856}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001857
Borislav Petkov9d950462013-01-20 10:24:28 +00001858/**
1859 * cpufreq_get_current_driver - return current driver's name
1860 *
1861 * Return the name string of the currently loaded cpufreq driver
1862 * or NULL, if none.
1863 */
1864const char *cpufreq_get_current_driver(void)
1865{
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001866 if (cpufreq_driver)
1867 return cpufreq_driver->name;
1868
1869 return NULL;
Borislav Petkov9d950462013-01-20 10:24:28 +00001870}
1871EXPORT_SYMBOL_GPL(cpufreq_get_current_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001872
Thomas Petazzoni51315cd2014-10-19 11:30:27 +02001873/**
1874 * cpufreq_get_driver_data - return current driver data
1875 *
1876 * Return the private data of the currently loaded cpufreq
1877 * driver, or NULL if no cpufreq driver is loaded.
1878 */
1879void *cpufreq_get_driver_data(void)
1880{
1881 if (cpufreq_driver)
1882 return cpufreq_driver->driver_data;
1883
1884 return NULL;
1885}
1886EXPORT_SYMBOL_GPL(cpufreq_get_driver_data);
1887
Linus Torvalds1da177e2005-04-16 15:20:36 -07001888/*********************************************************************
1889 * NOTIFIER LISTS INTERFACE *
1890 *********************************************************************/
1891
1892/**
1893 * cpufreq_register_notifier - register a driver with cpufreq
1894 * @nb: notifier function to register
1895 * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
1896 *
Dave Jones32ee8c32006-02-28 00:43:23 -05001897 * Add a driver to one of two lists: either a list of drivers that
Linus Torvalds1da177e2005-04-16 15:20:36 -07001898 * are notified about clock rate changes (once before and once after
1899 * the transition), or a list of drivers that are notified about
1900 * changes in cpufreq policy.
1901 *
1902 * This function may sleep, and has the same return conditions as
Alan Sterne041c682006-03-27 01:16:30 -08001903 * blocking_notifier_chain_register.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001904 */
1905int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
1906{
1907 int ret;
1908
Dirk Brandewied5aaffa2013-01-17 16:22:21 +00001909 if (cpufreq_disabled())
1910 return -EINVAL;
1911
Linus Torvalds1da177e2005-04-16 15:20:36 -07001912 switch (list) {
1913 case CPUFREQ_TRANSITION_NOTIFIER:
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02001914 mutex_lock(&cpufreq_fast_switch_lock);
1915
1916 if (cpufreq_fast_switch_count > 0) {
1917 mutex_unlock(&cpufreq_fast_switch_lock);
1918 return -EBUSY;
1919 }
Alan Sternb4dfdbb2006-10-04 02:17:06 -07001920 ret = srcu_notifier_chain_register(
Alan Sterne041c682006-03-27 01:16:30 -08001921 &cpufreq_transition_notifier_list, nb);
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02001922 if (!ret)
1923 cpufreq_fast_switch_count--;
1924
1925 mutex_unlock(&cpufreq_fast_switch_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001926 break;
1927 case CPUFREQ_POLICY_NOTIFIER:
Alan Sterne041c682006-03-27 01:16:30 -08001928 ret = blocking_notifier_chain_register(
1929 &cpufreq_policy_notifier_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001930 break;
1931 default:
1932 ret = -EINVAL;
1933 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001934
1935 return ret;
1936}
1937EXPORT_SYMBOL(cpufreq_register_notifier);
1938
Linus Torvalds1da177e2005-04-16 15:20:36 -07001939/**
1940 * cpufreq_unregister_notifier - unregister a driver with cpufreq
1941 * @nb: notifier block to be unregistered
Viresh Kumarbb176f72013-06-19 14:19:33 +05301942 * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
Linus Torvalds1da177e2005-04-16 15:20:36 -07001943 *
1944 * Remove a driver from the CPU frequency notifier list.
1945 *
1946 * This function may sleep, and has the same return conditions as
Alan Sterne041c682006-03-27 01:16:30 -08001947 * blocking_notifier_chain_unregister.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001948 */
1949int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
1950{
1951 int ret;
1952
Dirk Brandewied5aaffa2013-01-17 16:22:21 +00001953 if (cpufreq_disabled())
1954 return -EINVAL;
1955
Linus Torvalds1da177e2005-04-16 15:20:36 -07001956 switch (list) {
1957 case CPUFREQ_TRANSITION_NOTIFIER:
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02001958 mutex_lock(&cpufreq_fast_switch_lock);
1959
Alan Sternb4dfdbb2006-10-04 02:17:06 -07001960 ret = srcu_notifier_chain_unregister(
Alan Sterne041c682006-03-27 01:16:30 -08001961 &cpufreq_transition_notifier_list, nb);
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02001962 if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0))
1963 cpufreq_fast_switch_count++;
1964
1965 mutex_unlock(&cpufreq_fast_switch_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001966 break;
1967 case CPUFREQ_POLICY_NOTIFIER:
Alan Sterne041c682006-03-27 01:16:30 -08001968 ret = blocking_notifier_chain_unregister(
1969 &cpufreq_policy_notifier_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001970 break;
1971 default:
1972 ret = -EINVAL;
1973 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001974
1975 return ret;
1976}
1977EXPORT_SYMBOL(cpufreq_unregister_notifier);
1978
1979
1980/*********************************************************************
1981 * GOVERNORS *
1982 *********************************************************************/
1983
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02001984/**
1985 * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch.
1986 * @policy: cpufreq policy to switch the frequency for.
1987 * @target_freq: New frequency to set (may be approximate).
1988 *
1989 * Carry out a fast frequency switch without sleeping.
1990 *
1991 * The driver's ->fast_switch() callback invoked by this function must be
1992 * suitable for being called from within RCU-sched read-side critical sections
1993 * and it is expected to select the minimum available frequency greater than or
1994 * equal to @target_freq (CPUFREQ_RELATION_L).
1995 *
1996 * This function must not be called if policy->fast_switch_enabled is unset.
1997 *
1998 * Governors calling this function must guarantee that it will never be invoked
1999 * twice in parallel for the same policy and that it will never be called in
2000 * parallel with either ->target() or ->target_index() for the same policy.
2001 *
Viresh Kumar209887e2017-08-09 10:21:46 +05302002 * Returns the actual frequency set for the CPU.
2003 *
2004 * If 0 is returned by the driver's ->fast_switch() callback to indicate an
2005 * error condition, the hardware configuration must be preserved.
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02002006 */
2007unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,
2008 unsigned int target_freq)
2009{
Rafael J. Wysockib9af6942016-06-01 22:36:26 +02002010 target_freq = clamp_val(target_freq, policy->min, policy->max);
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02002011
2012 return cpufreq_driver->fast_switch(policy, target_freq);
2013}
2014EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch);
2015
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302016/* Must set freqs->new to intermediate frequency */
2017static int __target_intermediate(struct cpufreq_policy *policy,
2018 struct cpufreq_freqs *freqs, int index)
2019{
2020 int ret;
2021
2022 freqs->new = cpufreq_driver->get_intermediate(policy, index);
2023
2024 /* We don't need to switch to intermediate freq */
2025 if (!freqs->new)
2026 return 0;
2027
2028 pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n",
2029 __func__, policy->cpu, freqs->old, freqs->new);
2030
2031 cpufreq_freq_transition_begin(policy, freqs);
2032 ret = cpufreq_driver->target_intermediate(policy, index);
2033 cpufreq_freq_transition_end(policy, freqs, ret);
2034
2035 if (ret)
2036 pr_err("%s: Failed to change to intermediate frequency: %d\n",
2037 __func__, ret);
2038
2039 return ret;
2040}
2041
Viresh Kumar23727842016-06-03 10:58:50 +05302042static int __target_index(struct cpufreq_policy *policy, int index)
Viresh Kumar8d657752014-05-21 14:29:29 +05302043{
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302044 struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0};
2045 unsigned int intermediate_freq = 0;
Viresh Kumar23727842016-06-03 10:58:50 +05302046 unsigned int newfreq = policy->freq_table[index].frequency;
Viresh Kumar8d657752014-05-21 14:29:29 +05302047 int retval = -EINVAL;
2048 bool notify;
2049
Viresh Kumar23727842016-06-03 10:58:50 +05302050 if (newfreq == policy->cur)
2051 return 0;
2052
Viresh Kumar8d657752014-05-21 14:29:29 +05302053 notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION);
Viresh Kumar8d657752014-05-21 14:29:29 +05302054 if (notify) {
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302055 /* Handle switching to intermediate frequency */
2056 if (cpufreq_driver->get_intermediate) {
2057 retval = __target_intermediate(policy, &freqs, index);
2058 if (retval)
2059 return retval;
Viresh Kumar8d657752014-05-21 14:29:29 +05302060
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302061 intermediate_freq = freqs.new;
2062 /* Set old freq to intermediate */
2063 if (intermediate_freq)
2064 freqs.old = freqs.new;
2065 }
2066
Viresh Kumar23727842016-06-03 10:58:50 +05302067 freqs.new = newfreq;
Viresh Kumar8d657752014-05-21 14:29:29 +05302068 pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n",
2069 __func__, policy->cpu, freqs.old, freqs.new);
2070
2071 cpufreq_freq_transition_begin(policy, &freqs);
2072 }
2073
2074 retval = cpufreq_driver->target_index(policy, index);
2075 if (retval)
2076 pr_err("%s: Failed to change cpu frequency: %d\n", __func__,
2077 retval);
2078
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302079 if (notify) {
Viresh Kumar8d657752014-05-21 14:29:29 +05302080 cpufreq_freq_transition_end(policy, &freqs, retval);
2081
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302082 /*
2083 * Failed after setting to intermediate freq? Driver should have
2084 * reverted back to initial frequency and so should we. Check
2085 * here for intermediate_freq instead of get_intermediate, in
Shailendra Verma58405af2015-05-22 22:48:22 +05302086 * case we haven't switched to intermediate freq at all.
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302087 */
2088 if (unlikely(retval && intermediate_freq)) {
2089 freqs.old = intermediate_freq;
2090 freqs.new = policy->restore_freq;
2091 cpufreq_freq_transition_begin(policy, &freqs);
2092 cpufreq_freq_transition_end(policy, &freqs, 0);
2093 }
2094 }
2095
Viresh Kumar8d657752014-05-21 14:29:29 +05302096 return retval;
2097}
2098
Linus Torvalds1da177e2005-04-16 15:20:36 -07002099int __cpufreq_driver_target(struct cpufreq_policy *policy,
2100 unsigned int target_freq,
2101 unsigned int relation)
2102{
Viresh Kumar72499242012-10-31 01:28:21 +01002103 unsigned int old_target_freq = target_freq;
Viresh Kumard218ed72016-06-03 10:58:51 +05302104 int index;
Ashok Rajc32b6b82005-10-30 14:59:54 -08002105
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002106 if (cpufreq_disabled())
2107 return -ENODEV;
2108
Viresh Kumar72499242012-10-31 01:28:21 +01002109 /* Make sure that target_freq is within supported range */
Viresh Kumar910c6e82016-05-26 11:27:24 +05302110 target_freq = clamp_val(target_freq, policy->min, policy->max);
Viresh Kumar72499242012-10-31 01:28:21 +01002111
2112 pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07002113 policy->cpu, target_freq, relation, old_target_freq);
Viresh Kumar5a1c0222012-10-31 01:28:15 +01002114
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05302115 /*
2116 * This might look like a redundant call as we are checking it again
2117 * after finding index. But it is left intentionally for cases where
2118 * exactly same freq is called again and so we can save on few function
2119 * calls.
2120 */
Viresh Kumar5a1c0222012-10-31 01:28:15 +01002121 if (target_freq == policy->cur)
2122 return 0;
2123
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302124 /* Save last value to restore later on errors */
2125 policy->restore_freq = policy->cur;
2126
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002127 if (cpufreq_driver->target)
Rafael J. Wysocki6019d232016-02-26 00:03:01 +01002128 return cpufreq_driver->target(policy, target_freq, relation);
Ashok Raj90d45d12005-11-08 21:34:24 -08002129
Rafael J. Wysocki6019d232016-02-26 00:03:01 +01002130 if (!cpufreq_driver->target_index)
2131 return -EINVAL;
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05302132
Viresh Kumard218ed72016-06-03 10:58:51 +05302133 index = cpufreq_frequency_table_target(policy, target_freq, relation);
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05302134
Viresh Kumar23727842016-06-03 10:58:50 +05302135 return __target_index(policy, index);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002136}
2137EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
2138
Linus Torvalds1da177e2005-04-16 15:20:36 -07002139int cpufreq_driver_target(struct cpufreq_policy *policy,
2140 unsigned int target_freq,
2141 unsigned int relation)
2142{
Colin Ian King62c23a82019-08-13 13:21:21 +01002143 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002144
viresh kumarad7722d2013-10-18 19:10:15 +05302145 down_write(&policy->rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146
2147 ret = __cpufreq_driver_target(policy, target_freq, relation);
2148
viresh kumarad7722d2013-10-18 19:10:15 +05302149 up_write(&policy->rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002150
Linus Torvalds1da177e2005-04-16 15:20:36 -07002151 return ret;
2152}
2153EXPORT_SYMBOL_GPL(cpufreq_driver_target);
2154
Rafael J. Wysockide1df262016-02-05 02:37:42 +01002155__weak struct cpufreq_governor *cpufreq_fallback_governor(void)
2156{
2157 return NULL;
2158}
2159
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002160static int cpufreq_init_governor(struct cpufreq_policy *policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002161{
Dave Jonescc993ca2005-07-28 09:43:56 -07002162 int ret;
Thomas Renninger6afde102007-10-02 13:28:13 -07002163
Viresh Kumar2f0aea92014-03-04 11:00:26 +08002164 /* Don't start any governor operations if we are entering suspend */
2165 if (cpufreq_suspended)
2166 return 0;
Ethan Zhaocb57720b2014-12-18 15:28:19 +09002167 /*
2168 * Governor might not be initiated here if ACPI _PPC changed
2169 * notification happened, so check it.
2170 */
2171 if (!policy->governor)
2172 return -EINVAL;
Viresh Kumar2f0aea92014-03-04 11:00:26 +08002173
Viresh Kumared4676e2017-07-19 15:42:46 +05302174 /* Platform doesn't want dynamic frequency switching ? */
2175 if (policy->governor->dynamic_switching &&
Viresh Kumarfc4c7092017-07-19 15:42:49 +05302176 cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) {
Rafael J. Wysockide1df262016-02-05 02:37:42 +01002177 struct cpufreq_governor *gov = cpufreq_fallback_governor();
2178
2179 if (gov) {
Viresh Kumarfe829ed2017-07-19 15:42:48 +05302180 pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07002181 policy->governor->name, gov->name);
Thomas Renninger6afde102007-10-02 13:28:13 -07002182 policy->governor = gov;
Rafael J. Wysockide1df262016-02-05 02:37:42 +01002183 } else {
2184 return -EINVAL;
Thomas Renninger6afde102007-10-02 13:28:13 -07002185 }
Thomas Renninger1c256242007-10-02 13:28:12 -07002186 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002187
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002188 if (!try_module_get(policy->governor->owner))
2189 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002190
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002191 pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
Xiaoguang Chen95731eb2013-06-19 15:00:07 +08002192
Rafael J. Wysockie7888922016-06-02 23:24:15 +02002193 if (policy->governor->init) {
2194 ret = policy->governor->init(policy);
2195 if (ret) {
Rafael J. Wysocki36be3412016-05-12 15:13:35 +02002196 module_put(policy->governor->owner);
Rafael J. Wysockie7888922016-06-02 23:24:15 +02002197 return ret;
2198 }
Rafael J. Wysocki36be3412016-05-12 15:13:35 +02002199 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002200
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002201 return 0;
2202}
2203
2204static void cpufreq_exit_governor(struct cpufreq_policy *policy)
2205{
2206 if (cpufreq_suspended || !policy->governor)
2207 return;
2208
2209 pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
2210
Rafael J. Wysockie7888922016-06-02 23:24:15 +02002211 if (policy->governor->exit)
2212 policy->governor->exit(policy);
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002213
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002214 module_put(policy->governor->owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002215}
2216
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01002217static int cpufreq_start_governor(struct cpufreq_policy *policy)
2218{
2219 int ret;
2220
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002221 if (cpufreq_suspended)
2222 return 0;
2223
2224 if (!policy->governor)
2225 return -EINVAL;
2226
2227 pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
2228
Viresh Kumar407d0ff2019-06-20 08:35:46 +05302229 if (cpufreq_driver->get)
Viresh Kumar59807522019-06-20 08:35:49 +05302230 cpufreq_verify_current_freq(policy, false);
Rafael J. Wysocki3bbf8fe2016-03-21 15:47:48 +01002231
Rafael J. Wysockie7888922016-06-02 23:24:15 +02002232 if (policy->governor->start) {
2233 ret = policy->governor->start(policy);
2234 if (ret)
2235 return ret;
2236 }
Rafael J. Wysockid6ff44d2016-05-14 00:59:27 +02002237
Rafael J. Wysockie7888922016-06-02 23:24:15 +02002238 if (policy->governor->limits)
2239 policy->governor->limits(policy);
2240
Rafael J. Wysockid6ff44d2016-05-14 00:59:27 +02002241 return 0;
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01002242}
2243
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002244static void cpufreq_stop_governor(struct cpufreq_policy *policy)
2245{
2246 if (cpufreq_suspended || !policy->governor)
2247 return;
2248
2249 pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
2250
Rafael J. Wysockie7888922016-06-02 23:24:15 +02002251 if (policy->governor->stop)
2252 policy->governor->stop(policy);
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002253}
2254
2255static void cpufreq_governor_limits(struct cpufreq_policy *policy)
2256{
2257 if (cpufreq_suspended || !policy->governor)
2258 return;
2259
2260 pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
2261
Rafael J. Wysockie7888922016-06-02 23:24:15 +02002262 if (policy->governor->limits)
2263 policy->governor->limits(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002264}
2265
Linus Torvalds1da177e2005-04-16 15:20:36 -07002266int cpufreq_register_governor(struct cpufreq_governor *governor)
2267{
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -07002268 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002269
2270 if (!governor)
2271 return -EINVAL;
2272
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002273 if (cpufreq_disabled())
2274 return -ENODEV;
2275
akpm@osdl.org3fc54d32006-01-13 15:54:22 -08002276 mutex_lock(&cpufreq_governor_mutex);
Dave Jones32ee8c32006-02-28 00:43:23 -05002277
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -07002278 err = -EBUSY;
Viresh Kumar42f91fa2015-01-02 12:34:26 +05302279 if (!find_governor(governor->name)) {
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -07002280 err = 0;
2281 list_add(&governor->governor_list, &cpufreq_governor_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002282 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002283
Dave Jones32ee8c32006-02-28 00:43:23 -05002284 mutex_unlock(&cpufreq_governor_mutex);
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -07002285 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002286}
2287EXPORT_SYMBOL_GPL(cpufreq_register_governor);
2288
Linus Torvalds1da177e2005-04-16 15:20:36 -07002289void cpufreq_unregister_governor(struct cpufreq_governor *governor)
2290{
Viresh Kumar45732372015-05-12 12:22:34 +05302291 struct cpufreq_policy *policy;
2292 unsigned long flags;
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05002293
Linus Torvalds1da177e2005-04-16 15:20:36 -07002294 if (!governor)
2295 return;
2296
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002297 if (cpufreq_disabled())
2298 return;
2299
Viresh Kumar45732372015-05-12 12:22:34 +05302300 /* clear last_governor for all inactive policies */
2301 read_lock_irqsave(&cpufreq_driver_lock, flags);
2302 for_each_inactive_policy(policy) {
Viresh Kumar18bf3a12015-05-12 12:22:51 +05302303 if (!strcmp(policy->last_governor, governor->name)) {
2304 policy->governor = NULL;
Viresh Kumar45732372015-05-12 12:22:34 +05302305 strcpy(policy->last_governor, "\0");
Viresh Kumar18bf3a12015-05-12 12:22:51 +05302306 }
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05002307 }
Viresh Kumar45732372015-05-12 12:22:34 +05302308 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05002309
akpm@osdl.org3fc54d32006-01-13 15:54:22 -08002310 mutex_lock(&cpufreq_governor_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002311 list_del(&governor->governor_list);
akpm@osdl.org3fc54d32006-01-13 15:54:22 -08002312 mutex_unlock(&cpufreq_governor_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002313}
2314EXPORT_SYMBOL_GPL(cpufreq_unregister_governor);
2315
2316
Linus Torvalds1da177e2005-04-16 15:20:36 -07002317/*********************************************************************
2318 * POLICY INTERFACE *
2319 *********************************************************************/
2320
2321/**
2322 * cpufreq_get_policy - get the current cpufreq_policy
Dave Jones29464f22009-01-18 01:37:11 -05002323 * @policy: struct cpufreq_policy into which the current cpufreq_policy
2324 * is written
Linus Torvalds1da177e2005-04-16 15:20:36 -07002325 *
2326 * Reads the current cpufreq policy.
2327 */
2328int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
2329{
2330 struct cpufreq_policy *cpu_policy;
2331 if (!policy)
2332 return -EINVAL;
2333
2334 cpu_policy = cpufreq_cpu_get(cpu);
2335 if (!cpu_policy)
2336 return -EINVAL;
2337
Viresh Kumard5b73cd2013-08-06 22:53:06 +05302338 memcpy(policy, cpu_policy, sizeof(*policy));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002339
2340 cpufreq_cpu_put(cpu_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002341 return 0;
2342}
2343EXPORT_SYMBOL(cpufreq_get_policy);
2344
Rafael J. Wysockia0dbb812019-02-20 00:22:51 +01002345/**
2346 * cpufreq_set_policy - Modify cpufreq policy parameters.
2347 * @policy: Policy object to modify.
2348 * @new_policy: New policy data.
2349 *
2350 * Pass @new_policy to the cpufreq driver's ->verify() callback, run the
2351 * installed policy notifiers for it with the CPUFREQ_ADJUST value, pass it to
2352 * the driver's ->verify() callback again and run the notifiers for it again
2353 * with the CPUFREQ_NOTIFY value. Next, copy the min and max parameters
2354 * of @new_policy to @policy and either invoke the driver's ->setpolicy()
2355 * callback (if present) or carry out a governor update for @policy. That is,
2356 * run the current governor's ->limits() callback (if the governor field in
2357 * @new_policy points to the same object as the one in @policy) or replace the
2358 * governor for @policy with the new one stored in @new_policy.
2359 *
2360 * The cpuinfo part of @policy is not updated by this function.
Arjan van de Ven153d7f32006-07-26 15:40:07 +02002361 */
Rafael J. Wysocki9083e492019-03-26 12:19:52 +01002362int cpufreq_set_policy(struct cpufreq_policy *policy,
2363 struct cpufreq_policy *new_policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002364{
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002365 struct cpufreq_governor *old_gov;
Viresh Kumar67d874c2019-07-08 16:27:52 +05302366 struct device *cpu_dev = get_cpu_device(policy->cpu);
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002367 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002368
Joe Perchese837f9b2014-03-11 10:03:00 -07002369 pr_debug("setting new policy for CPU %u: %u - %u kHz\n",
2370 new_policy->cpu, new_policy->min, new_policy->max);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002371
Viresh Kumard5b73cd2013-08-06 22:53:06 +05302372 memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002373
Pan Xinhuifba95732015-07-30 18:10:40 +08002374 /*
Viresh Kumar67d874c2019-07-08 16:27:52 +05302375 * PM QoS framework collects all the requests from users and provide us
2376 * the final aggregated value here.
2377 */
Viresh Kumar18c49922019-07-05 16:21:24 +05302378 new_policy->min = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MIN_FREQUENCY);
2379 new_policy->max = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MAX_FREQUENCY);
Mattia Dongili9c9a43e2006-07-05 23:12:20 +02002380
Linus Torvalds1da177e2005-04-16 15:20:36 -07002381 /* verify the cpu speed can be set within this limit */
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302382 ret = cpufreq_driver->verify(new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002383 if (ret)
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002384 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002385
Viresh Kumar67d874c2019-07-08 16:27:52 +05302386 /*
2387 * The notifier-chain shall be removed once all the users of
2388 * CPUFREQ_ADJUST are moved to use the QoS framework.
2389 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002390 /* adjust if necessary - all reasons */
Alan Sterne041c682006-03-27 01:16:30 -08002391 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302392 CPUFREQ_ADJUST, new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002393
Viresh Kumarbb176f72013-06-19 14:19:33 +05302394 /*
2395 * verify the cpu speed can be set within this limit, which might be
2396 * different to the first one
2397 */
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302398 ret = cpufreq_driver->verify(new_policy);
Alan Sterne041c682006-03-27 01:16:30 -08002399 if (ret)
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002400 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002401
2402 /* notification of the new policy */
Alan Sterne041c682006-03-27 01:16:30 -08002403 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302404 CPUFREQ_NOTIFY, new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002405
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302406 policy->min = new_policy->min;
2407 policy->max = new_policy->max;
Ruchi Kandoi601b2182018-07-24 10:35:44 -07002408 trace_cpu_frequency_limits(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002409
Steve Mucklee3c06232016-07-13 13:25:25 -07002410 policy->cached_target_freq = UINT_MAX;
2411
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002412 pr_debug("new min and max freqs are %u - %u kHz\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07002413 policy->min, policy->max);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002414
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002415 if (cpufreq_driver->setpolicy) {
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302416 policy->policy = new_policy->policy;
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002417 pr_debug("setting range\n");
Rafael J. Wysocki167a38d2019-02-20 00:26:30 +01002418 return cpufreq_driver->setpolicy(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002419 }
2420
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01002421 if (new_policy->governor == policy->governor) {
Rafael J. Wysocki2bb40592019-02-20 00:25:18 +01002422 pr_debug("governor limits update\n");
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002423 cpufreq_governor_limits(policy);
Rafael J. Wysockid6ff44d2016-05-14 00:59:27 +02002424 return 0;
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01002425 }
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002426
2427 pr_debug("governor switch\n");
2428
2429 /* save old, working values */
2430 old_gov = policy->governor;
2431 /* end old governor */
2432 if (old_gov) {
Rafael J. Wysocki45482c72016-05-12 15:14:12 +02002433 cpufreq_stop_governor(policy);
Rafael J. Wysocki36be3412016-05-12 15:13:35 +02002434 cpufreq_exit_governor(policy);
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002435 }
2436
2437 /* start new governor */
2438 policy->governor = new_policy->governor;
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002439 ret = cpufreq_init_governor(policy);
Viresh Kumar4bc384a2015-07-18 11:31:03 +05302440 if (!ret) {
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01002441 ret = cpufreq_start_governor(policy);
2442 if (!ret) {
Rafael J. Wysocki2bb40592019-02-20 00:25:18 +01002443 pr_debug("governor change\n");
Quentin Perret531b5c92018-12-03 09:56:21 +00002444 sched_cpufreq_governor_change(policy, old_gov);
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01002445 return 0;
2446 }
Rafael J. Wysockib7898fd2016-03-30 03:47:49 +02002447 cpufreq_exit_governor(policy);
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002448 }
2449
2450 /* new governor failed, so re-start old one */
2451 pr_debug("starting governor %s failed\n", policy->governor->name);
2452 if (old_gov) {
2453 policy->governor = old_gov;
Rafael J. Wysockia92604b2016-05-14 01:01:46 +02002454 if (cpufreq_init_governor(policy))
Viresh Kumar4bc384a2015-07-18 11:31:03 +05302455 policy->governor = NULL;
2456 else
Rafael J. Wysocki0a300762016-03-21 15:45:24 +01002457 cpufreq_start_governor(policy);
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002458 }
2459
Viresh Kumar4bc384a2015-07-18 11:31:03 +05302460 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002461}
2462
2463/**
Rafael J. Wysockia0dbb812019-02-20 00:22:51 +01002464 * cpufreq_update_policy - Re-evaluate an existing cpufreq policy.
2465 * @cpu: CPU to re-evaluate the policy for.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002466 *
Rafael J. Wysockia0dbb812019-02-20 00:22:51 +01002467 * Update the current frequency for the cpufreq policy of @cpu and use
Viresh Kumar18c49922019-07-05 16:21:24 +05302468 * cpufreq_set_policy() to re-apply the min and max limits, which triggers the
2469 * evaluation of policy notifiers and the cpufreq driver's ->verify() callback
2470 * for the policy in question, among other things.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002471 */
Rafael J. Wysocki30248fe2016-11-18 13:59:21 +01002472void cpufreq_update_policy(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002473{
Rafael J. Wysocki540a37582019-03-26 12:16:58 +01002474 struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002475
Aaron Plattnerfefa8ff2014-06-18 11:27:32 -07002476 if (!policy)
Rafael J. Wysocki30248fe2016-11-18 13:59:21 +01002477 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002478
Viresh Kumarbb176f72013-06-19 14:19:33 +05302479 /*
2480 * BIOS might change freq behind our back
2481 * -> ask driver for current freq and notify governors about a change
2482 */
Viresh Kumar5ddc6d42019-06-20 08:35:48 +05302483 if (cpufreq_driver->get && has_target() &&
Viresh Kumar59807522019-06-20 08:35:49 +05302484 (cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false))))
Rafael J. Wysocki348a2ec2019-02-20 00:24:25 +01002485 goto unlock;
Rafael J. Wysocki30248fe2016-11-18 13:59:21 +01002486
Viresh Kumar70a59fd2019-06-20 08:35:50 +05302487 refresh_frequency_limits(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002488
Aaron Plattnerfefa8ff2014-06-18 11:27:32 -07002489unlock:
Rafael J. Wysocki540a37582019-03-26 12:16:58 +01002490 cpufreq_cpu_release(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002491}
2492EXPORT_SYMBOL(cpufreq_update_policy);
2493
Rafael J. Wysocki5a25e3f2019-03-26 12:15:13 +01002494/**
2495 * cpufreq_update_limits - Update policy limits for a given CPU.
2496 * @cpu: CPU to update the policy limits for.
2497 *
2498 * Invoke the driver's ->update_limits callback if present or call
2499 * cpufreq_update_policy() for @cpu.
2500 */
2501void cpufreq_update_limits(unsigned int cpu)
2502{
2503 if (cpufreq_driver->update_limits)
2504 cpufreq_driver->update_limits(cpu);
2505 else
2506 cpufreq_update_policy(cpu);
2507}
2508EXPORT_SYMBOL_GPL(cpufreq_update_limits);
2509
Linus Torvalds1da177e2005-04-16 15:20:36 -07002510/*********************************************************************
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002511 * BOOST *
2512 *********************************************************************/
2513static int cpufreq_boost_set_sw(int state)
2514{
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002515 struct cpufreq_policy *policy;
2516 int ret = -EINVAL;
2517
Viresh Kumarf9637352015-05-12 12:20:11 +05302518 for_each_active_policy(policy) {
Viresh Kumarf8bfc112016-06-03 10:58:47 +05302519 if (!policy->freq_table)
2520 continue;
Viresh Kumar49f18562016-02-11 17:31:12 +05302521
Viresh Kumarf8bfc112016-06-03 10:58:47 +05302522 ret = cpufreq_frequency_table_cpuinfo(policy,
2523 policy->freq_table);
2524 if (ret) {
2525 pr_err("%s: Policy frequency update failed\n",
2526 __func__);
2527 break;
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002528 }
Viresh Kumarf8bfc112016-06-03 10:58:47 +05302529
Viresh Kumar18c49922019-07-05 16:21:24 +05302530 ret = dev_pm_qos_update_request(policy->max_freq_req, policy->max);
Viresh Kumare61a4122019-08-09 08:01:17 +05302531 if (ret < 0)
Viresh Kumar18c49922019-07-05 16:21:24 +05302532 break;
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002533 }
2534
2535 return ret;
2536}
2537
2538int cpufreq_boost_trigger_state(int state)
2539{
2540 unsigned long flags;
2541 int ret = 0;
2542
2543 if (cpufreq_driver->boost_enabled == state)
2544 return 0;
2545
2546 write_lock_irqsave(&cpufreq_driver_lock, flags);
2547 cpufreq_driver->boost_enabled = state;
2548 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
2549
2550 ret = cpufreq_driver->set_boost(state);
2551 if (ret) {
2552 write_lock_irqsave(&cpufreq_driver_lock, flags);
2553 cpufreq_driver->boost_enabled = !state;
2554 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
2555
Joe Perchese837f9b2014-03-11 10:03:00 -07002556 pr_err("%s: Cannot %s BOOST\n",
2557 __func__, state ? "enable" : "disable");
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002558 }
2559
2560 return ret;
2561}
2562
Rafael J. Wysocki41669da2015-12-27 00:23:48 +01002563static bool cpufreq_boost_supported(void)
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002564{
Yue Hu89f98d72019-04-09 10:25:36 +08002565 return cpufreq_driver->set_boost;
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002566}
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002567
Viresh Kumar44139ed2015-07-29 16:23:09 +05302568static int create_boost_sysfs_file(void)
2569{
2570 int ret;
2571
Viresh Kumarc82bd442015-10-15 21:35:23 +05302572 ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr);
Viresh Kumar44139ed2015-07-29 16:23:09 +05302573 if (ret)
2574 pr_err("%s: cannot register global BOOST sysfs file\n",
2575 __func__);
2576
2577 return ret;
2578}
2579
2580static void remove_boost_sysfs_file(void)
2581{
2582 if (cpufreq_boost_supported())
Viresh Kumarc82bd442015-10-15 21:35:23 +05302583 sysfs_remove_file(cpufreq_global_kobject, &boost.attr);
Viresh Kumar44139ed2015-07-29 16:23:09 +05302584}
2585
2586int cpufreq_enable_boost_support(void)
2587{
2588 if (!cpufreq_driver)
2589 return -EINVAL;
2590
2591 if (cpufreq_boost_supported())
2592 return 0;
2593
Rafael J. Wysocki7a6c79f2015-12-27 00:27:38 +01002594 cpufreq_driver->set_boost = cpufreq_boost_set_sw;
Viresh Kumar44139ed2015-07-29 16:23:09 +05302595
2596 /* This will get removed on driver unregister */
2597 return create_boost_sysfs_file();
2598}
2599EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support);
2600
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002601int cpufreq_boost_enabled(void)
2602{
2603 return cpufreq_driver->boost_enabled;
2604}
2605EXPORT_SYMBOL_GPL(cpufreq_boost_enabled);
2606
2607/*********************************************************************
Linus Torvalds1da177e2005-04-16 15:20:36 -07002608 * REGISTER / UNREGISTER CPUFREQ DRIVER *
2609 *********************************************************************/
Sebastian Andrzej Siewior27622b02016-09-06 19:04:48 +02002610static enum cpuhp_state hp_online;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002611
Chen Yuc4a3fa22017-04-09 13:45:16 +08002612static int cpuhp_cpufreq_online(unsigned int cpu)
2613{
2614 cpufreq_online(cpu);
2615
2616 return 0;
2617}
2618
2619static int cpuhp_cpufreq_offline(unsigned int cpu)
2620{
2621 cpufreq_offline(cpu);
2622
2623 return 0;
2624}
2625
Linus Torvalds1da177e2005-04-16 15:20:36 -07002626/**
2627 * cpufreq_register_driver - register a CPU Frequency driver
2628 * @driver_data: A struct cpufreq_driver containing the values#
2629 * submitted by the CPU Frequency driver.
2630 *
Viresh Kumarbb176f72013-06-19 14:19:33 +05302631 * Registers a CPU Frequency driver to this core code. This code
Eric Biggers63af4052016-02-20 21:50:01 -06002632 * returns zero on success, -EEXIST when another driver got here first
Dave Jones32ee8c32006-02-28 00:43:23 -05002633 * (and isn't unregistered in the meantime).
Linus Torvalds1da177e2005-04-16 15:20:36 -07002634 *
2635 */
Linus Torvalds221dee22007-02-26 14:55:48 -08002636int cpufreq_register_driver(struct cpufreq_driver *driver_data)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002637{
2638 unsigned long flags;
2639 int ret;
2640
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002641 if (cpufreq_disabled())
2642 return -ENODEV;
2643
Linus Torvalds1da177e2005-04-16 15:20:36 -07002644 if (!driver_data || !driver_data->verify || !driver_data->init ||
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05302645 !(driver_data->setpolicy || driver_data->target_index ||
Rafael J. Wysocki98322352014-03-19 12:48:30 +01002646 driver_data->target) ||
2647 (driver_data->setpolicy && (driver_data->target_index ||
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302648 driver_data->target)) ||
Viresh Kumara9a22b52019-02-14 16:16:21 +05302649 (!driver_data->get_intermediate != !driver_data->target_intermediate) ||
Viresh Kumar91a12e92019-02-12 16:36:04 +05302650 (!driver_data->online != !driver_data->offline))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002651 return -EINVAL;
2652
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002653 pr_debug("trying to register driver %s\n", driver_data->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002654
Rafael J. Wysockifdd320d2015-07-30 01:45:07 +02002655 /* Protect against concurrent CPU online/offline. */
Sebastian Andrzej Siewiora92551e2017-05-24 10:15:20 +02002656 cpus_read_lock();
Rafael J. Wysockifdd320d2015-07-30 01:45:07 +02002657
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002658 write_lock_irqsave(&cpufreq_driver_lock, flags);
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002659 if (cpufreq_driver) {
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002660 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Rafael J. Wysockifdd320d2015-07-30 01:45:07 +02002661 ret = -EEXIST;
2662 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002663 }
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002664 cpufreq_driver = driver_data;
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002665 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002666
Viresh Kumarbc68b7d2015-01-02 12:34:30 +05302667 if (driver_data->setpolicy)
2668 driver_data->flags |= CPUFREQ_CONST_LOOPS;
2669
Rafael J. Wysocki7a6c79f2015-12-27 00:27:38 +01002670 if (cpufreq_boost_supported()) {
2671 ret = create_boost_sysfs_file();
2672 if (ret)
2673 goto err_null_driver;
2674 }
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002675
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002676 ret = subsys_interface_register(&cpufreq_interface);
Jiri Slaby8f5bc2a2011-03-01 17:41:10 +01002677 if (ret)
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002678 goto err_boost_unreg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002679
Viresh Kumarce1bcfe2015-01-02 12:34:35 +05302680 if (!(cpufreq_driver->flags & CPUFREQ_STICKY) &&
2681 list_empty(&cpufreq_policy_list)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002682 /* if all ->init() calls failed, unregister */
David Arcari6c770032017-05-26 11:37:31 -04002683 ret = -ENODEV;
Viresh Kumarce1bcfe2015-01-02 12:34:35 +05302684 pr_debug("%s: No CPU initialized for driver %s\n", __func__,
2685 driver_data->name);
2686 goto err_if_unreg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002687 }
2688
Sebastian Andrzej Siewiora92551e2017-05-24 10:15:20 +02002689 ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN,
2690 "cpufreq:online",
2691 cpuhp_cpufreq_online,
2692 cpuhp_cpufreq_offline);
Sebastian Andrzej Siewior27622b02016-09-06 19:04:48 +02002693 if (ret < 0)
2694 goto err_if_unreg;
2695 hp_online = ret;
Sebastian Andrzej Siewior5372e052016-09-20 16:56:28 +02002696 ret = 0;
Sebastian Andrzej Siewior27622b02016-09-06 19:04:48 +02002697
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002698 pr_debug("driver %s up and running\n", driver_data->name);
Pankaj Gupta3834abb2016-05-16 11:07:19 +00002699 goto out;
Rafael J. Wysockifdd320d2015-07-30 01:45:07 +02002700
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002701err_if_unreg:
2702 subsys_interface_unregister(&cpufreq_interface);
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002703err_boost_unreg:
Viresh Kumar44139ed2015-07-29 16:23:09 +05302704 remove_boost_sysfs_file();
Jiri Slaby8f5bc2a2011-03-01 17:41:10 +01002705err_null_driver:
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002706 write_lock_irqsave(&cpufreq_driver_lock, flags);
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002707 cpufreq_driver = NULL;
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002708 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Pankaj Gupta3834abb2016-05-16 11:07:19 +00002709out:
Sebastian Andrzej Siewiora92551e2017-05-24 10:15:20 +02002710 cpus_read_unlock();
Pankaj Gupta3834abb2016-05-16 11:07:19 +00002711 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002712}
2713EXPORT_SYMBOL_GPL(cpufreq_register_driver);
2714
Linus Torvalds1da177e2005-04-16 15:20:36 -07002715/**
2716 * cpufreq_unregister_driver - unregister the current CPUFreq driver
2717 *
Viresh Kumarbb176f72013-06-19 14:19:33 +05302718 * Unregister the current CPUFreq driver. Only call this if you have
Linus Torvalds1da177e2005-04-16 15:20:36 -07002719 * the right to do so, i.e. if you have succeeded in initialising before!
2720 * Returns zero if successful, and -EINVAL if the cpufreq_driver is
2721 * currently not initialised.
2722 */
Linus Torvalds221dee22007-02-26 14:55:48 -08002723int cpufreq_unregister_driver(struct cpufreq_driver *driver)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002724{
2725 unsigned long flags;
2726
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002727 if (!cpufreq_driver || (driver != cpufreq_driver))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002728 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002729
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002730 pr_debug("unregistering driver %s\n", driver->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002731
Sebastian Andrzej Siewior454d3a22015-07-22 17:59:11 +02002732 /* Protect against concurrent cpu hotplug */
Sebastian Andrzej Siewiora92551e2017-05-24 10:15:20 +02002733 cpus_read_lock();
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002734 subsys_interface_unregister(&cpufreq_interface);
Viresh Kumar44139ed2015-07-29 16:23:09 +05302735 remove_boost_sysfs_file();
Sebastian Andrzej Siewiora92551e2017-05-24 10:15:20 +02002736 cpuhp_remove_state_nocalls_cpuslocked(hp_online);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002737
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002738 write_lock_irqsave(&cpufreq_driver_lock, flags);
Viresh Kumar6eed9402013-08-06 22:53:11 +05302739
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002740 cpufreq_driver = NULL;
Viresh Kumar6eed9402013-08-06 22:53:11 +05302741
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002742 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Sebastian Andrzej Siewiora92551e2017-05-24 10:15:20 +02002743 cpus_read_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002744
2745 return 0;
2746}
2747EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002748
Doug Anderson90de2a42014-12-23 22:09:48 -08002749/*
2750 * Stop cpufreq at shutdown to make sure it isn't holding any locks
2751 * or mutexes when secondary CPUs are halted.
2752 */
2753static struct syscore_ops cpufreq_syscore_ops = {
2754 .shutdown = cpufreq_suspend,
2755};
2756
Viresh Kumarc82bd442015-10-15 21:35:23 +05302757struct kobject *cpufreq_global_kobject;
2758EXPORT_SYMBOL(cpufreq_global_kobject);
2759
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002760static int __init cpufreq_core_init(void)
2761{
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002762 if (cpufreq_disabled())
2763 return -ENODEV;
2764
Viresh Kumar8eec1022015-10-15 21:35:22 +05302765 cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj);
Thomas Renninger8aa84ad2009-07-24 15:25:05 +02002766 BUG_ON(!cpufreq_global_kobject);
2767
Doug Anderson90de2a42014-12-23 22:09:48 -08002768 register_syscore_ops(&cpufreq_syscore_ops);
2769
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002770 return 0;
2771}
Len Brownd82f2692017-02-28 16:44:16 -05002772module_param(off, int, 0444);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002773core_initcall(cpufreq_core_init);