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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/drivers/cpufreq/cpufreq.c
3 *
4 * Copyright (C) 2001 Russell King
5 * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
Viresh Kumarbb176f72013-06-19 14:19:33 +05306 * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
Ashok Rajc32b6b82005-10-30 14:59:54 -08008 * Oct 2005 - Ashok Raj <ashok.raj@intel.com>
Dave Jones32ee8c32006-02-28 00:43:23 -05009 * Added handling for CPU hotplug
Dave Jones8ff69732006-03-05 03:37:23 -050010 * Feb 2006 - Jacob Shin <jacob.shin@amd.com>
11 * Fix handling for CPU hotplug -- affected CPUs
Ashok Rajc32b6b82005-10-30 14:59:54 -080012 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License version 2 as
15 * published by the Free Software Foundation.
Linus Torvalds1da177e2005-04-16 15:20:36 -070016 */
17
Viresh Kumardb701152012-10-23 01:29:03 +020018#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
Viresh Kumar5ff0a262013-08-06 22:53:03 +053020#include <linux/cpu.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/cpufreq.h>
22#include <linux/delay.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/device.h>
Viresh Kumar5ff0a262013-08-06 22:53:03 +053024#include <linux/init.h>
25#include <linux/kernel_stat.h>
26#include <linux/module.h>
akpm@osdl.org3fc54d32006-01-13 15:54:22 -080027#include <linux/mutex.h>
Viresh Kumar5ff0a262013-08-06 22:53:03 +053028#include <linux/slab.h>
Viresh Kumar2f0aea92014-03-04 11:00:26 +080029#include <linux/suspend.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
Linus Torvalds1da177e2005-04-16 15:20:36 -070033/**
Dave Jonescd878472006-08-11 17:59:28 -040034 * The "cpufreq driver" - the arch- or hardware-dependent low
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 * level driver of CPUFreq support, and its spinlock. This lock
36 * also protects the cpufreq_cpu_data array.
37 */
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +020038static struct cpufreq_driver *cpufreq_driver;
Mike Travis7a6aedf2008-03-25 15:06:53 -070039static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
Srivatsa S. Bhat84148092013-07-30 04:25:10 +053040static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback);
Viresh Kumarbb176f72013-06-19 14:19:33 +053041static DEFINE_RWLOCK(cpufreq_driver_lock);
Jane Li6f1e4ef2014-01-03 17:17:41 +080042DEFINE_MUTEX(cpufreq_governor_lock);
Lukasz Majewskic88a1f82013-08-06 22:53:08 +053043static LIST_HEAD(cpufreq_policy_list);
Viresh Kumarbb176f72013-06-19 14:19:33 +053044
Thomas Renninger084f3492007-07-09 11:35:28 -070045/* This one keeps track of the previously set governor of a removed CPU */
Dmitry Monakhove77b89f2009-10-05 00:38:55 +040046static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
Viresh Kumar2f0aea92014-03-04 11:00:26 +080048/* Flag to suspend/resume CPUFreq governors */
49static bool cpufreq_suspended;
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +053051static inline bool has_target(void)
52{
53 return cpufreq_driver->target_index || cpufreq_driver->target;
54}
55
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -080056/*
Viresh Kumar6eed9402013-08-06 22:53:11 +053057 * rwsem to guarantee that cpufreq driver module doesn't unload during critical
58 * sections
59 */
60static DECLARE_RWSEM(cpufreq_rwsem);
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062/* internal prototypes */
Dave Jones29464f22009-01-18 01:37:11 -050063static int __cpufreq_governor(struct cpufreq_policy *policy,
64 unsigned int event);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -080065static unsigned int __cpufreq_get(unsigned int cpu);
David Howells65f27f32006-11-22 14:55:48 +000066static void handle_update(struct work_struct *work);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
68/**
Dave Jones32ee8c32006-02-28 00:43:23 -050069 * Two notifier lists: the "policy" list is involved in the
70 * validation process for a new CPU frequency policy; the
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 * "transition" list for kernel code that needs to handle
72 * changes to devices when the CPU clock speed changes.
73 * The mutex locks both lists.
74 */
Alan Sterne041c682006-03-27 01:16:30 -080075static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
Alan Sternb4dfdbb2006-10-04 02:17:06 -070076static struct srcu_notifier_head cpufreq_transition_notifier_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
Cesar Eduardo Barros74212ca2008-02-16 08:41:24 -020078static bool init_cpufreq_transition_notifier_list_called;
Alan Sternb4dfdbb2006-10-04 02:17:06 -070079static int __init init_cpufreq_transition_notifier_list(void)
80{
81 srcu_init_notifier_head(&cpufreq_transition_notifier_list);
Cesar Eduardo Barros74212ca2008-02-16 08:41:24 -020082 init_cpufreq_transition_notifier_list_called = true;
Alan Sternb4dfdbb2006-10-04 02:17:06 -070083 return 0;
84}
Linus Torvaldsb3438f82006-11-20 11:47:18 -080085pure_initcall(init_cpufreq_transition_notifier_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -070086
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -040087static int off __read_mostly;
Viresh Kumarda584452012-10-26 00:51:32 +020088static int cpufreq_disabled(void)
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -040089{
90 return off;
91}
92void disable_cpufreq(void)
93{
94 off = 1;
95}
Linus Torvalds1da177e2005-04-16 15:20:36 -070096static LIST_HEAD(cpufreq_governor_list);
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
120 cur_wall_time = jiffies64_to_cputime64(get_jiffies_64());
121
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)
131 *wall = cputime_to_usecs(cur_wall_time);
132
133 return cputime_to_usecs(idle_time);
134}
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
Viresh Kumar70e9e772013-10-03 20:29:07 +0530149/*
150 * This is a generic cpufreq init() routine which can be used by cpufreq
151 * drivers of SMP systems. It will do following:
152 * - validate & show freq table passed
153 * - set policies transition latency
154 * - policy->cpus with all possible CPUs
155 */
156int cpufreq_generic_init(struct cpufreq_policy *policy,
157 struct cpufreq_frequency_table *table,
158 unsigned int transition_latency)
159{
160 int ret;
161
162 ret = cpufreq_table_validate_and_show(policy, table);
163 if (ret) {
164 pr_err("%s: invalid frequency table: %d\n", __func__, ret);
165 return ret;
166 }
167
168 policy->cpuinfo.transition_latency = transition_latency;
169
170 /*
171 * The driver only supports the SMP configuartion where all processors
172 * share the clock and voltage and clock.
173 */
174 cpumask_setall(policy->cpus);
175
176 return 0;
177}
178EXPORT_SYMBOL_GPL(cpufreq_generic_init);
179
Viresh Kumar652ed952014-01-09 20:38:43 +0530180unsigned int cpufreq_generic_get(unsigned int cpu)
181{
182 struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
183
184 if (!policy || IS_ERR(policy->clk)) {
Joe Perchese837f9b2014-03-11 10:03:00 -0700185 pr_err("%s: No %s associated to cpu: %d\n",
186 __func__, policy ? "clk" : "policy", cpu);
Viresh Kumar652ed952014-01-09 20:38:43 +0530187 return 0;
188 }
189
190 return clk_get_rate(policy->clk) / 1000;
191}
192EXPORT_SYMBOL_GPL(cpufreq_generic_get);
193
Viresh Kumare0b31652014-03-10 14:53:33 +0530194/* Only for cpufreq core internal use */
195struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
196{
197 return per_cpu(cpufreq_cpu_data, cpu);
198}
199
Viresh Kumar6eed9402013-08-06 22:53:11 +0530200struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201{
Viresh Kumar6eed9402013-08-06 22:53:11 +0530202 struct cpufreq_policy *policy = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203 unsigned long flags;
204
Viresh Kumar6eed9402013-08-06 22:53:11 +0530205 if (cpufreq_disabled() || (cpu >= nr_cpu_ids))
206 return NULL;
207
208 if (!down_read_trylock(&cpufreq_rwsem))
209 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
211 /* get the cpufreq driver */
Nathan Zimmer0d1857a2013-02-22 16:24:34 +0000212 read_lock_irqsave(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213
Viresh Kumar6eed9402013-08-06 22:53:11 +0530214 if (cpufreq_driver) {
215 /* get the CPU */
216 policy = per_cpu(cpufreq_cpu_data, cpu);
217 if (policy)
218 kobject_get(&policy->kobj);
219 }
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200220
Viresh Kumar6eed9402013-08-06 22:53:11 +0530221 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
Viresh Kumar3a3e9e02013-08-06 22:53:05 +0530223 if (!policy)
Viresh Kumar6eed9402013-08-06 22:53:11 +0530224 up_read(&cpufreq_rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225
Viresh Kumar3a3e9e02013-08-06 22:53:05 +0530226 return policy;
Stephen Boyda9144432012-07-20 18:14:38 +0000227}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
229
Viresh Kumar3a3e9e02013-08-06 22:53:05 +0530230void cpufreq_cpu_put(struct cpufreq_policy *policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231{
Dirk Brandewied5aaffa2013-01-17 16:22:21 +0000232 if (cpufreq_disabled())
233 return;
234
Viresh Kumar6eed9402013-08-06 22:53:11 +0530235 kobject_put(&policy->kobj);
236 up_read(&cpufreq_rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237}
238EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
239
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240/*********************************************************************
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 * EXTERNALLY AFFECTING FREQUENCY CHANGES *
242 *********************************************************************/
243
244/**
245 * adjust_jiffies - adjust the system "loops_per_jiffy"
246 *
247 * This function alters the system "loops_per_jiffy" for the clock
248 * speed change. Note that loops_per_jiffy cannot be updated on SMP
Dave Jones32ee8c32006-02-28 00:43:23 -0500249 * systems as each CPU might be scaled differently. So, use the arch
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250 * per-CPU loops_per_jiffy value wherever possible.
251 */
252#ifndef CONFIG_SMP
253static unsigned long l_p_j_ref;
Viresh Kumarbb176f72013-06-19 14:19:33 +0530254static unsigned int l_p_j_ref_freq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
Arjan van de Ven858119e2006-01-14 13:20:43 -0800256static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257{
258 if (ci->flags & CPUFREQ_CONST_LOOPS)
259 return;
260
261 if (!l_p_j_ref_freq) {
262 l_p_j_ref = loops_per_jiffy;
263 l_p_j_ref_freq = ci->old;
Joe Perchese837f9b2014-03-11 10:03:00 -0700264 pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n",
265 l_p_j_ref, l_p_j_ref_freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 }
Viresh Kumar0b443ea2014-03-19 11:24:58 +0530267 if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) {
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530268 loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
269 ci->new);
Joe Perchese837f9b2014-03-11 10:03:00 -0700270 pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n",
271 loops_per_jiffy, ci->new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 }
273}
274#else
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530275static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
276{
277 return;
278}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279#endif
280
Viresh Kumar0956df9c2013-06-19 14:19:34 +0530281static void __cpufreq_notify_transition(struct cpufreq_policy *policy,
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530282 struct cpufreq_freqs *freqs, unsigned int state)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283{
284 BUG_ON(irqs_disabled());
285
Dirk Brandewied5aaffa2013-01-17 16:22:21 +0000286 if (cpufreq_disabled())
287 return;
288
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200289 freqs->flags = cpufreq_driver->flags;
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200290 pr_debug("notification %u of frequency transition to %u kHz\n",
Joe Perchese837f9b2014-03-11 10:03:00 -0700291 state, freqs->new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 switch (state) {
Dave Jonese4472cb2006-01-31 15:53:55 -0800294
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 case CPUFREQ_PRECHANGE:
Dave Jones32ee8c32006-02-28 00:43:23 -0500296 /* detect if the driver reported a value as "old frequency"
Dave Jonese4472cb2006-01-31 15:53:55 -0800297 * which is not equal to what the cpufreq core thinks is
298 * "old frequency".
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 */
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200300 if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
Dave Jonese4472cb2006-01-31 15:53:55 -0800301 if ((policy) && (policy->cpu == freqs->cpu) &&
302 (policy->cur) && (policy->cur != freqs->old)) {
Joe Perchese837f9b2014-03-11 10:03:00 -0700303 pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n",
304 freqs->old, policy->cur);
Dave Jonese4472cb2006-01-31 15:53:55 -0800305 freqs->old = policy->cur;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 }
307 }
Alan Sternb4dfdbb2006-10-04 02:17:06 -0700308 srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
Alan Sterne041c682006-03-27 01:16:30 -0800309 CPUFREQ_PRECHANGE, freqs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
311 break;
Dave Jonese4472cb2006-01-31 15:53:55 -0800312
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 case CPUFREQ_POSTCHANGE:
314 adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
Joe Perchese837f9b2014-03-11 10:03:00 -0700315 pr_debug("FREQ: %lu - CPU: %lu\n",
316 (unsigned long)freqs->new, (unsigned long)freqs->cpu);
Thomas Renninger25e41932011-01-03 17:50:44 +0100317 trace_cpu_frequency(freqs->new, freqs->cpu);
Alan Sternb4dfdbb2006-10-04 02:17:06 -0700318 srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
Alan Sterne041c682006-03-27 01:16:30 -0800319 CPUFREQ_POSTCHANGE, freqs);
Dave Jonese4472cb2006-01-31 15:53:55 -0800320 if (likely(policy) && likely(policy->cpu == freqs->cpu))
321 policy->cur = freqs->new;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 break;
323 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324}
Viresh Kumarbb176f72013-06-19 14:19:33 +0530325
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530326/**
327 * cpufreq_notify_transition - call notifier chain and adjust_jiffies
328 * on frequency transition.
329 *
330 * This function calls the transition notifiers and the "adjust_jiffies"
331 * function. It is called twice on all CPU frequency changes that have
332 * external effects.
333 */
Viresh Kumar236a9802014-03-24 13:35:46 +0530334static void cpufreq_notify_transition(struct cpufreq_policy *policy,
Viresh Kumarb43a7ff2013-03-24 11:56:43 +0530335 struct cpufreq_freqs *freqs, unsigned int state)
336{
337 for_each_cpu(freqs->cpu, policy->cpus)
338 __cpufreq_notify_transition(policy, freqs, state);
339}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
Viresh Kumarf7ba3b42013-12-02 11:04:12 +0530341/* Do post notifications when there are chances that transition has failed */
Viresh Kumar236a9802014-03-24 13:35:46 +0530342static void cpufreq_notify_post_transition(struct cpufreq_policy *policy,
Viresh Kumarf7ba3b42013-12-02 11:04:12 +0530343 struct cpufreq_freqs *freqs, int transition_failed)
344{
345 cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
346 if (!transition_failed)
347 return;
348
349 swap(freqs->old, freqs->new);
350 cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
351 cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
352}
Viresh Kumarf7ba3b42013-12-02 11:04:12 +0530353
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530354void cpufreq_freq_transition_begin(struct cpufreq_policy *policy,
355 struct cpufreq_freqs *freqs)
356{
Srivatsa S. Bhatca654dc2014-05-05 12:52:39 +0530357
358 /*
359 * Catch double invocations of _begin() which lead to self-deadlock.
360 * ASYNC_NOTIFICATION drivers are left out because the cpufreq core
361 * doesn't invoke _begin() on their behalf, and hence the chances of
362 * double invocations are very low. Moreover, there are scenarios
363 * where these checks can emit false-positive warnings in these
364 * drivers; so we avoid that by skipping them altogether.
365 */
366 WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION)
367 && current == policy->transition_task);
368
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530369wait:
370 wait_event(policy->transition_wait, !policy->transition_ongoing);
371
372 spin_lock(&policy->transition_lock);
373
374 if (unlikely(policy->transition_ongoing)) {
375 spin_unlock(&policy->transition_lock);
376 goto wait;
377 }
378
379 policy->transition_ongoing = true;
Srivatsa S. Bhatca654dc2014-05-05 12:52:39 +0530380 policy->transition_task = current;
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530381
382 spin_unlock(&policy->transition_lock);
383
384 cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
385}
386EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin);
387
388void cpufreq_freq_transition_end(struct cpufreq_policy *policy,
389 struct cpufreq_freqs *freqs, int transition_failed)
390{
391 if (unlikely(WARN_ON(!policy->transition_ongoing)))
392 return;
393
394 cpufreq_notify_post_transition(policy, freqs, transition_failed);
395
396 policy->transition_ongoing = false;
Srivatsa S. Bhatca654dc2014-05-05 12:52:39 +0530397 policy->transition_task = NULL;
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +0530398
399 wake_up(&policy->transition_wait);
400}
401EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end);
402
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404/*********************************************************************
405 * SYSFS INTERFACE *
406 *********************************************************************/
Rashika Kheria8a5c74a2014-02-26 22:12:42 +0530407static ssize_t show_boost(struct kobject *kobj,
Lukasz Majewski6f19efc2013-12-20 15:24:49 +0100408 struct attribute *attr, char *buf)
409{
410 return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled);
411}
412
413static ssize_t store_boost(struct kobject *kobj, struct attribute *attr,
414 const char *buf, size_t count)
415{
416 int ret, enable;
417
418 ret = sscanf(buf, "%d", &enable);
419 if (ret != 1 || enable < 0 || enable > 1)
420 return -EINVAL;
421
422 if (cpufreq_boost_trigger_state(enable)) {
Joe Perchese837f9b2014-03-11 10:03:00 -0700423 pr_err("%s: Cannot %s BOOST!\n",
424 __func__, enable ? "enable" : "disable");
Lukasz Majewski6f19efc2013-12-20 15:24:49 +0100425 return -EINVAL;
426 }
427
Joe Perchese837f9b2014-03-11 10:03:00 -0700428 pr_debug("%s: cpufreq BOOST %s\n",
429 __func__, enable ? "enabled" : "disabled");
Lukasz Majewski6f19efc2013-12-20 15:24:49 +0100430
431 return count;
432}
433define_one_global_rw(boost);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700435static struct cpufreq_governor *__find_governor(const char *str_governor)
436{
437 struct cpufreq_governor *t;
438
439 list_for_each_entry(t, &cpufreq_governor_list, governor_list)
Dave Jones29464f22009-01-18 01:37:11 -0500440 if (!strnicmp(str_governor, t->name, CPUFREQ_NAME_LEN))
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700441 return t;
442
443 return NULL;
444}
445
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446/**
447 * cpufreq_parse_governor - parse a governor string
448 */
Dave Jones905d77c2008-03-05 14:28:32 -0500449static int cpufreq_parse_governor(char *str_governor, unsigned int *policy,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 struct cpufreq_governor **governor)
451{
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700452 int err = -EINVAL;
453
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200454 if (!cpufreq_driver)
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700455 goto out;
456
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200457 if (cpufreq_driver->setpolicy) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) {
459 *policy = CPUFREQ_POLICY_PERFORMANCE;
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700460 err = 0;
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530461 } else if (!strnicmp(str_governor, "powersave",
462 CPUFREQ_NAME_LEN)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 *policy = CPUFREQ_POLICY_POWERSAVE;
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700464 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 }
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530466 } else if (has_target()) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 struct cpufreq_governor *t;
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700468
akpm@osdl.org3fc54d32006-01-13 15:54:22 -0800469 mutex_lock(&cpufreq_governor_mutex);
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700470
471 t = __find_governor(str_governor);
472
Jeremy Fitzhardingeea714972006-07-06 12:32:01 -0700473 if (t == NULL) {
Kees Cook1a8e1462011-05-04 08:38:56 -0700474 int ret;
Jeremy Fitzhardingeea714972006-07-06 12:32:01 -0700475
Kees Cook1a8e1462011-05-04 08:38:56 -0700476 mutex_unlock(&cpufreq_governor_mutex);
477 ret = request_module("cpufreq_%s", str_governor);
478 mutex_lock(&cpufreq_governor_mutex);
Jeremy Fitzhardingeea714972006-07-06 12:32:01 -0700479
Kees Cook1a8e1462011-05-04 08:38:56 -0700480 if (ret == 0)
481 t = __find_governor(str_governor);
Jeremy Fitzhardingeea714972006-07-06 12:32:01 -0700482 }
483
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700484 if (t != NULL) {
485 *governor = t;
486 err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 }
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700488
akpm@osdl.org3fc54d32006-01-13 15:54:22 -0800489 mutex_unlock(&cpufreq_governor_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 }
Dave Jones29464f22009-01-18 01:37:11 -0500491out:
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -0700492 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495/**
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530496 * cpufreq_per_cpu_attr_read() / show_##file_name() -
497 * print out cpufreq information
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 *
499 * Write out information from cpufreq_driver->policy[cpu]; object must be
500 * "unsigned int".
501 */
502
Dave Jones32ee8c32006-02-28 00:43:23 -0500503#define show_one(file_name, object) \
504static ssize_t show_##file_name \
Dave Jones905d77c2008-03-05 14:28:32 -0500505(struct cpufreq_policy *policy, char *buf) \
Dave Jones32ee8c32006-02-28 00:43:23 -0500506{ \
Dave Jones29464f22009-01-18 01:37:11 -0500507 return sprintf(buf, "%u\n", policy->object); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508}
509
510show_one(cpuinfo_min_freq, cpuinfo.min_freq);
511show_one(cpuinfo_max_freq, cpuinfo.max_freq);
Thomas Renningered129782009-02-04 01:17:41 +0100512show_one(cpuinfo_transition_latency, cpuinfo.transition_latency);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513show_one(scaling_min_freq, min);
514show_one(scaling_max_freq, max);
515show_one(scaling_cur_freq, cur);
516
Viresh Kumar037ce832013-10-02 14:13:16 +0530517static int cpufreq_set_policy(struct cpufreq_policy *policy,
Viresh Kumar3a3e9e02013-08-06 22:53:05 +0530518 struct cpufreq_policy *new_policy);
Thomas Renninger7970e082006-04-13 15:14:04 +0200519
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520/**
521 * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access
522 */
523#define store_one(file_name, object) \
524static ssize_t store_##file_name \
Dave Jones905d77c2008-03-05 14:28:32 -0500525(struct cpufreq_policy *policy, const char *buf, size_t count) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526{ \
Srivatsa S. Bhat5136fa52013-09-07 01:24:06 +0530527 int ret; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528 struct cpufreq_policy new_policy; \
529 \
530 ret = cpufreq_get_policy(&new_policy, policy->cpu); \
531 if (ret) \
532 return -EINVAL; \
533 \
Dave Jones29464f22009-01-18 01:37:11 -0500534 ret = sscanf(buf, "%u", &new_policy.object); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 if (ret != 1) \
536 return -EINVAL; \
537 \
Viresh Kumar037ce832013-10-02 14:13:16 +0530538 ret = cpufreq_set_policy(policy, &new_policy); \
Thomas Renninger7970e082006-04-13 15:14:04 +0200539 policy->user_policy.object = policy->object; \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 \
541 return ret ? ret : count; \
542}
543
Dave Jones29464f22009-01-18 01:37:11 -0500544store_one(scaling_min_freq, min);
545store_one(scaling_max_freq, max);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546
547/**
548 * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware
549 */
Dave Jones905d77c2008-03-05 14:28:32 -0500550static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy,
551 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552{
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -0800553 unsigned int cur_freq = __cpufreq_get(policy->cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 if (!cur_freq)
555 return sprintf(buf, "<unknown>");
556 return sprintf(buf, "%u\n", cur_freq);
557}
558
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559/**
560 * show_scaling_governor - show the current policy for the specified CPU
561 */
Dave Jones905d77c2008-03-05 14:28:32 -0500562static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563{
Dave Jones29464f22009-01-18 01:37:11 -0500564 if (policy->policy == CPUFREQ_POLICY_POWERSAVE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 return sprintf(buf, "powersave\n");
566 else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE)
567 return sprintf(buf, "performance\n");
568 else if (policy->governor)
viresh kumar4b972f02012-10-23 01:23:43 +0200569 return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n",
Dave Jones29464f22009-01-18 01:37:11 -0500570 policy->governor->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 return -EINVAL;
572}
573
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574/**
575 * store_scaling_governor - store policy for the specified CPU
576 */
Dave Jones905d77c2008-03-05 14:28:32 -0500577static ssize_t store_scaling_governor(struct cpufreq_policy *policy,
578 const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579{
Srivatsa S. Bhat5136fa52013-09-07 01:24:06 +0530580 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 char str_governor[16];
582 struct cpufreq_policy new_policy;
583
584 ret = cpufreq_get_policy(&new_policy, policy->cpu);
585 if (ret)
586 return ret;
587
Dave Jones29464f22009-01-18 01:37:11 -0500588 ret = sscanf(buf, "%15s", str_governor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 if (ret != 1)
590 return -EINVAL;
591
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530592 if (cpufreq_parse_governor(str_governor, &new_policy.policy,
593 &new_policy.governor))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594 return -EINVAL;
595
Viresh Kumar037ce832013-10-02 14:13:16 +0530596 ret = cpufreq_set_policy(policy, &new_policy);
Thomas Renninger7970e082006-04-13 15:14:04 +0200597
598 policy->user_policy.policy = policy->policy;
599 policy->user_policy.governor = policy->governor;
Thomas Renninger7970e082006-04-13 15:14:04 +0200600
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530601 if (ret)
602 return ret;
603 else
604 return count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605}
606
607/**
608 * show_scaling_driver - show the cpufreq driver currently loaded
609 */
Dave Jones905d77c2008-03-05 14:28:32 -0500610static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611{
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200612 return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613}
614
615/**
616 * show_scaling_available_governors - show the available CPUfreq governors
617 */
Dave Jones905d77c2008-03-05 14:28:32 -0500618static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy,
619 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620{
621 ssize_t i = 0;
622 struct cpufreq_governor *t;
623
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530624 if (!has_target()) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 i += sprintf(buf, "performance powersave");
626 goto out;
627 }
628
629 list_for_each_entry(t, &cpufreq_governor_list, governor_list) {
Dave Jones29464f22009-01-18 01:37:11 -0500630 if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char))
631 - (CPUFREQ_NAME_LEN + 2)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632 goto out;
viresh kumar4b972f02012-10-23 01:23:43 +0200633 i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 }
Dave Jones7d5e3502006-02-02 17:03:42 -0500635out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 i += sprintf(&buf[i], "\n");
637 return i;
638}
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700639
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800640ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641{
642 ssize_t i = 0;
643 unsigned int cpu;
644
Rusty Russell835481d2009-01-04 05:18:06 -0800645 for_each_cpu(cpu, mask) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 if (i)
647 i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " ");
648 i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu);
649 if (i >= (PAGE_SIZE - 5))
Dave Jones29464f22009-01-18 01:37:11 -0500650 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 }
652 i += sprintf(&buf[i], "\n");
653 return i;
654}
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800655EXPORT_SYMBOL_GPL(cpufreq_show_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700657/**
658 * show_related_cpus - show the CPUs affected by each transition even if
659 * hw coordination is in use
660 */
661static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
662{
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800663 return cpufreq_show_cpus(policy->related_cpus, buf);
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700664}
665
666/**
667 * show_affected_cpus - show the CPUs affected by each transition
668 */
669static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf)
670{
Lan Tianyuf4fd3792013-06-27 15:08:54 +0800671 return cpufreq_show_cpus(policy->cpus, buf);
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700672}
673
Venki Pallipadi9e769882007-10-26 10:18:21 -0700674static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
Dave Jones905d77c2008-03-05 14:28:32 -0500675 const char *buf, size_t count)
Venki Pallipadi9e769882007-10-26 10:18:21 -0700676{
677 unsigned int freq = 0;
678 unsigned int ret;
679
CHIKAMA masaki879000f2008-06-05 22:46:33 -0700680 if (!policy->governor || !policy->governor->store_setspeed)
Venki Pallipadi9e769882007-10-26 10:18:21 -0700681 return -EINVAL;
682
683 ret = sscanf(buf, "%u", &freq);
684 if (ret != 1)
685 return -EINVAL;
686
687 policy->governor->store_setspeed(policy, freq);
688
689 return count;
690}
691
692static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf)
693{
CHIKAMA masaki879000f2008-06-05 22:46:33 -0700694 if (!policy->governor || !policy->governor->show_setspeed)
Venki Pallipadi9e769882007-10-26 10:18:21 -0700695 return sprintf(buf, "<unsupported>\n");
696
697 return policy->governor->show_setspeed(policy, buf);
698}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699
Thomas Renningere2f74f32009-11-19 12:31:01 +0100700/**
viresh kumar8bf1ac722012-10-23 01:23:33 +0200701 * show_bios_limit - show the current cpufreq HW/BIOS limitation
Thomas Renningere2f74f32009-11-19 12:31:01 +0100702 */
703static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf)
704{
705 unsigned int limit;
706 int ret;
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200707 if (cpufreq_driver->bios_limit) {
708 ret = cpufreq_driver->bios_limit(policy->cpu, &limit);
Thomas Renningere2f74f32009-11-19 12:31:01 +0100709 if (!ret)
710 return sprintf(buf, "%u\n", limit);
711 }
712 return sprintf(buf, "%u\n", policy->cpuinfo.max_freq);
713}
714
Borislav Petkov6dad2a22010-03-31 21:56:46 +0200715cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400);
716cpufreq_freq_attr_ro(cpuinfo_min_freq);
717cpufreq_freq_attr_ro(cpuinfo_max_freq);
718cpufreq_freq_attr_ro(cpuinfo_transition_latency);
719cpufreq_freq_attr_ro(scaling_available_governors);
720cpufreq_freq_attr_ro(scaling_driver);
721cpufreq_freq_attr_ro(scaling_cur_freq);
722cpufreq_freq_attr_ro(bios_limit);
723cpufreq_freq_attr_ro(related_cpus);
724cpufreq_freq_attr_ro(affected_cpus);
725cpufreq_freq_attr_rw(scaling_min_freq);
726cpufreq_freq_attr_rw(scaling_max_freq);
727cpufreq_freq_attr_rw(scaling_governor);
728cpufreq_freq_attr_rw(scaling_setspeed);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729
Dave Jones905d77c2008-03-05 14:28:32 -0500730static struct attribute *default_attrs[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 &cpuinfo_min_freq.attr,
732 &cpuinfo_max_freq.attr,
Thomas Renningered129782009-02-04 01:17:41 +0100733 &cpuinfo_transition_latency.attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 &scaling_min_freq.attr,
735 &scaling_max_freq.attr,
736 &affected_cpus.attr,
Darrick J. Wonge8628dd2008-04-18 13:31:12 -0700737 &related_cpus.attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 &scaling_governor.attr,
739 &scaling_driver.attr,
740 &scaling_available_governors.attr,
Venki Pallipadi9e769882007-10-26 10:18:21 -0700741 &scaling_setspeed.attr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 NULL
743};
744
Dave Jones29464f22009-01-18 01:37:11 -0500745#define to_policy(k) container_of(k, struct cpufreq_policy, kobj)
746#define to_attr(a) container_of(a, struct freq_attr, attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
Dave Jones29464f22009-01-18 01:37:11 -0500748static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749{
Dave Jones905d77c2008-03-05 14:28:32 -0500750 struct cpufreq_policy *policy = to_policy(kobj);
751 struct freq_attr *fattr = to_attr(attr);
Viresh Kumar1b750e32013-10-02 14:13:09 +0530752 ssize_t ret;
Viresh Kumar6eed9402013-08-06 22:53:11 +0530753
754 if (!down_read_trylock(&cpufreq_rwsem))
Viresh Kumar1b750e32013-10-02 14:13:09 +0530755 return -EINVAL;
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -0800756
viresh kumarad7722d2013-10-18 19:10:15 +0530757 down_read(&policy->rwsem);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -0800758
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530759 if (fattr->show)
760 ret = fattr->show(policy, buf);
761 else
762 ret = -EIO;
763
viresh kumarad7722d2013-10-18 19:10:15 +0530764 up_read(&policy->rwsem);
Viresh Kumar6eed9402013-08-06 22:53:11 +0530765 up_read(&cpufreq_rwsem);
Viresh Kumar1b750e32013-10-02 14:13:09 +0530766
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 return ret;
768}
769
Dave Jones905d77c2008-03-05 14:28:32 -0500770static ssize_t store(struct kobject *kobj, struct attribute *attr,
771 const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772{
Dave Jones905d77c2008-03-05 14:28:32 -0500773 struct cpufreq_policy *policy = to_policy(kobj);
774 struct freq_attr *fattr = to_attr(attr);
Dave Jonesa07530b2008-03-05 14:22:25 -0500775 ssize_t ret = -EINVAL;
Viresh Kumar6eed9402013-08-06 22:53:11 +0530776
Srivatsa S. Bhat4f750c92013-09-07 01:23:43 +0530777 get_online_cpus();
778
779 if (!cpu_online(policy->cpu))
780 goto unlock;
781
Viresh Kumar6eed9402013-08-06 22:53:11 +0530782 if (!down_read_trylock(&cpufreq_rwsem))
Srivatsa S. Bhat4f750c92013-09-07 01:23:43 +0530783 goto unlock;
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -0800784
viresh kumarad7722d2013-10-18 19:10:15 +0530785 down_write(&policy->rwsem);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -0800786
Gautham R Shenoye08f5f52006-10-26 16:20:58 +0530787 if (fattr->store)
788 ret = fattr->store(policy, buf, count);
789 else
790 ret = -EIO;
791
viresh kumarad7722d2013-10-18 19:10:15 +0530792 up_write(&policy->rwsem);
Viresh Kumar6eed9402013-08-06 22:53:11 +0530793
Viresh Kumar6eed9402013-08-06 22:53:11 +0530794 up_read(&cpufreq_rwsem);
Srivatsa S. Bhat4f750c92013-09-07 01:23:43 +0530795unlock:
796 put_online_cpus();
797
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 return ret;
799}
800
Dave Jones905d77c2008-03-05 14:28:32 -0500801static void cpufreq_sysfs_release(struct kobject *kobj)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802{
Dave Jones905d77c2008-03-05 14:28:32 -0500803 struct cpufreq_policy *policy = to_policy(kobj);
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200804 pr_debug("last reference is dropped\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 complete(&policy->kobj_unregister);
806}
807
Emese Revfy52cf25d2010-01-19 02:58:23 +0100808static const struct sysfs_ops sysfs_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809 .show = show,
810 .store = store,
811};
812
813static struct kobj_type ktype_cpufreq = {
814 .sysfs_ops = &sysfs_ops,
815 .default_attrs = default_attrs,
816 .release = cpufreq_sysfs_release,
817};
818
Viresh Kumar2361be22013-05-17 16:09:09 +0530819struct kobject *cpufreq_global_kobject;
820EXPORT_SYMBOL(cpufreq_global_kobject);
821
822static int cpufreq_global_kobject_usage;
823
824int cpufreq_get_global_kobject(void)
825{
826 if (!cpufreq_global_kobject_usage++)
827 return kobject_add(cpufreq_global_kobject,
828 &cpu_subsys.dev_root->kobj, "%s", "cpufreq");
829
830 return 0;
831}
832EXPORT_SYMBOL(cpufreq_get_global_kobject);
833
834void cpufreq_put_global_kobject(void)
835{
836 if (!--cpufreq_global_kobject_usage)
837 kobject_del(cpufreq_global_kobject);
838}
839EXPORT_SYMBOL(cpufreq_put_global_kobject);
840
841int cpufreq_sysfs_create_file(const struct attribute *attr)
842{
843 int ret = cpufreq_get_global_kobject();
844
845 if (!ret) {
846 ret = sysfs_create_file(cpufreq_global_kobject, attr);
847 if (ret)
848 cpufreq_put_global_kobject();
849 }
850
851 return ret;
852}
853EXPORT_SYMBOL(cpufreq_sysfs_create_file);
854
855void cpufreq_sysfs_remove_file(const struct attribute *attr)
856{
857 sysfs_remove_file(cpufreq_global_kobject, attr);
858 cpufreq_put_global_kobject();
859}
860EXPORT_SYMBOL(cpufreq_sysfs_remove_file);
861
Dave Jones19d6f7e2009-07-08 17:35:39 -0400862/* symlink affected CPUs */
Viresh Kumar308b60e2013-07-31 14:35:14 +0200863static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy)
Dave Jones19d6f7e2009-07-08 17:35:39 -0400864{
865 unsigned int j;
866 int ret = 0;
867
868 for_each_cpu(j, policy->cpus) {
Kay Sievers8a25a2f2011-12-21 14:29:42 -0800869 struct device *cpu_dev;
Dave Jones19d6f7e2009-07-08 17:35:39 -0400870
Viresh Kumar308b60e2013-07-31 14:35:14 +0200871 if (j == policy->cpu)
Dave Jones19d6f7e2009-07-08 17:35:39 -0400872 continue;
Dave Jones19d6f7e2009-07-08 17:35:39 -0400873
Viresh Kumare8fdde12013-07-31 14:31:33 +0200874 pr_debug("Adding link for CPU: %u\n", j);
Kay Sievers8a25a2f2011-12-21 14:29:42 -0800875 cpu_dev = get_cpu_device(j);
876 ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj,
Dave Jones19d6f7e2009-07-08 17:35:39 -0400877 "cpufreq");
Rafael J. Wysocki71c34612013-08-04 01:19:34 +0200878 if (ret)
879 break;
Dave Jones19d6f7e2009-07-08 17:35:39 -0400880 }
881 return ret;
882}
883
Viresh Kumar308b60e2013-07-31 14:35:14 +0200884static int cpufreq_add_dev_interface(struct cpufreq_policy *policy,
Kay Sievers8a25a2f2011-12-21 14:29:42 -0800885 struct device *dev)
Dave Jones909a6942009-07-08 18:05:42 -0400886{
887 struct freq_attr **drv_attr;
Dave Jones909a6942009-07-08 18:05:42 -0400888 int ret = 0;
Dave Jones909a6942009-07-08 18:05:42 -0400889
890 /* prepare interface data */
891 ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq,
Kay Sievers8a25a2f2011-12-21 14:29:42 -0800892 &dev->kobj, "cpufreq");
Dave Jones909a6942009-07-08 18:05:42 -0400893 if (ret)
894 return ret;
895
896 /* set up files for this cpu device */
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200897 drv_attr = cpufreq_driver->attr;
Dave Jones909a6942009-07-08 18:05:42 -0400898 while ((drv_attr) && (*drv_attr)) {
899 ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
900 if (ret)
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200901 goto err_out_kobj_put;
Dave Jones909a6942009-07-08 18:05:42 -0400902 drv_attr++;
903 }
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200904 if (cpufreq_driver->get) {
Dave Jones909a6942009-07-08 18:05:42 -0400905 ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr);
906 if (ret)
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200907 goto err_out_kobj_put;
Dave Jones909a6942009-07-08 18:05:42 -0400908 }
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530909 if (has_target()) {
Dave Jones909a6942009-07-08 18:05:42 -0400910 ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
911 if (ret)
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200912 goto err_out_kobj_put;
Dave Jones909a6942009-07-08 18:05:42 -0400913 }
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200914 if (cpufreq_driver->bios_limit) {
Thomas Renningere2f74f32009-11-19 12:31:01 +0100915 ret = sysfs_create_file(&policy->kobj, &bios_limit.attr);
916 if (ret)
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200917 goto err_out_kobj_put;
Thomas Renningere2f74f32009-11-19 12:31:01 +0100918 }
Dave Jones909a6942009-07-08 18:05:42 -0400919
Viresh Kumar308b60e2013-07-31 14:35:14 +0200920 ret = cpufreq_add_dev_symlink(policy);
Dave Jonesecf7e462009-07-08 18:48:47 -0400921 if (ret)
922 goto err_out_kobj_put;
923
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +0530924 return ret;
925
926err_out_kobj_put:
927 kobject_put(&policy->kobj);
928 wait_for_completion(&policy->kobj_unregister);
929 return ret;
930}
931
932static void cpufreq_init_policy(struct cpufreq_policy *policy)
933{
viresh kumar6e2c89d2014-03-04 11:43:59 +0800934 struct cpufreq_governor *gov = NULL;
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +0530935 struct cpufreq_policy new_policy;
936 int ret = 0;
937
Viresh Kumard5b73cd2013-08-06 22:53:06 +0530938 memcpy(&new_policy, policy, sizeof(*policy));
Jason Barona27a9ab2013-12-19 22:50:50 +0000939
viresh kumar6e2c89d2014-03-04 11:43:59 +0800940 /* Update governor of new_policy to the governor used before hotplug */
941 gov = __find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu));
942 if (gov)
943 pr_debug("Restoring governor %s for cpu %d\n",
944 policy->governor->name, policy->cpu);
945 else
946 gov = CPUFREQ_DEFAULT_GOVERNOR;
947
948 new_policy.governor = gov;
949
Jason Barona27a9ab2013-12-19 22:50:50 +0000950 /* Use the default policy if its valid. */
951 if (cpufreq_driver->setpolicy)
viresh kumar6e2c89d2014-03-04 11:43:59 +0800952 cpufreq_parse_governor(gov->name, &new_policy.policy, NULL);
Dave Jonesecf7e462009-07-08 18:48:47 -0400953
954 /* set default policy */
Viresh Kumar037ce832013-10-02 14:13:16 +0530955 ret = cpufreq_set_policy(policy, &new_policy);
Dave Jonesecf7e462009-07-08 18:48:47 -0400956 if (ret) {
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +0200957 pr_debug("setting policy failed\n");
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +0200958 if (cpufreq_driver->exit)
959 cpufreq_driver->exit(policy);
Dave Jonesecf7e462009-07-08 18:48:47 -0400960 }
Dave Jones909a6942009-07-08 18:05:42 -0400961}
962
Viresh Kumarfcf80582013-01-29 14:39:08 +0000963#ifdef CONFIG_HOTPLUG_CPU
Viresh Kumard8d3b472013-08-04 01:20:07 +0200964static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy,
Viresh Kumar42f921a2013-12-20 21:26:02 +0530965 unsigned int cpu, struct device *dev)
Viresh Kumarfcf80582013-01-29 14:39:08 +0000966{
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530967 int ret = 0;
Viresh Kumarfcf80582013-01-29 14:39:08 +0000968 unsigned long flags;
969
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530970 if (has_target()) {
Viresh Kumar3de9bde2013-08-06 22:53:13 +0530971 ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
972 if (ret) {
973 pr_err("%s: Failed to stop governor\n", __func__);
974 return ret;
975 }
976 }
Viresh Kumarfcf80582013-01-29 14:39:08 +0000977
viresh kumarad7722d2013-10-18 19:10:15 +0530978 down_write(&policy->rwsem);
Viresh Kumar2eaa3e22013-02-07 10:55:00 +0530979
Nathan Zimmer0d1857a2013-02-22 16:24:34 +0000980 write_lock_irqsave(&cpufreq_driver_lock, flags);
Viresh Kumar2eaa3e22013-02-07 10:55:00 +0530981
Viresh Kumarfcf80582013-01-29 14:39:08 +0000982 cpumask_set_cpu(cpu, policy->cpus);
983 per_cpu(cpufreq_cpu_data, cpu) = policy;
Nathan Zimmer0d1857a2013-02-22 16:24:34 +0000984 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Viresh Kumarfcf80582013-01-29 14:39:08 +0000985
viresh kumarad7722d2013-10-18 19:10:15 +0530986 up_write(&policy->rwsem);
Viresh Kumar2eaa3e22013-02-07 10:55:00 +0530987
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +0530988 if (has_target()) {
Stratos Karafotise5c87b72014-03-19 23:29:17 +0200989 ret = __cpufreq_governor(policy, CPUFREQ_GOV_START);
990 if (!ret)
991 ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
992
993 if (ret) {
Viresh Kumar3de9bde2013-08-06 22:53:13 +0530994 pr_err("%s: Failed to start governor\n", __func__);
995 return ret;
996 }
Viresh Kumar820c6ca2013-04-22 00:48:03 +0200997 }
Viresh Kumarfcf80582013-01-29 14:39:08 +0000998
Viresh Kumar42f921a2013-12-20 21:26:02 +0530999 return sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq");
Viresh Kumarfcf80582013-01-29 14:39:08 +00001000}
1001#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301003static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu)
1004{
1005 struct cpufreq_policy *policy;
1006 unsigned long flags;
1007
Lan Tianyu44871c92013-09-11 15:05:05 +08001008 read_lock_irqsave(&cpufreq_driver_lock, flags);
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301009
1010 policy = per_cpu(cpufreq_cpu_data_fallback, cpu);
1011
Lan Tianyu44871c92013-09-11 15:05:05 +08001012 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301013
viresh kumar6e2c89d2014-03-04 11:43:59 +08001014 policy->governor = NULL;
1015
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301016 return policy;
1017}
1018
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301019static struct cpufreq_policy *cpufreq_policy_alloc(void)
1020{
1021 struct cpufreq_policy *policy;
1022
1023 policy = kzalloc(sizeof(*policy), GFP_KERNEL);
1024 if (!policy)
1025 return NULL;
1026
1027 if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL))
1028 goto err_free_policy;
1029
1030 if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL))
1031 goto err_free_cpumask;
1032
Lukasz Majewskic88a1f82013-08-06 22:53:08 +05301033 INIT_LIST_HEAD(&policy->policy_list);
viresh kumarad7722d2013-10-18 19:10:15 +05301034 init_rwsem(&policy->rwsem);
Srivatsa S. Bhat12478cf2014-03-24 13:35:44 +05301035 spin_lock_init(&policy->transition_lock);
1036 init_waitqueue_head(&policy->transition_wait);
viresh kumarad7722d2013-10-18 19:10:15 +05301037
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301038 return policy;
1039
1040err_free_cpumask:
1041 free_cpumask_var(policy->cpus);
1042err_free_policy:
1043 kfree(policy);
1044
1045 return NULL;
1046}
1047
Viresh Kumar42f921a2013-12-20 21:26:02 +05301048static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy)
1049{
1050 struct kobject *kobj;
1051 struct completion *cmp;
1052
Viresh Kumarfcd7af92014-01-07 07:10:10 +05301053 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
1054 CPUFREQ_REMOVE_POLICY, policy);
1055
Viresh Kumar42f921a2013-12-20 21:26:02 +05301056 down_read(&policy->rwsem);
1057 kobj = &policy->kobj;
1058 cmp = &policy->kobj_unregister;
1059 up_read(&policy->rwsem);
1060 kobject_put(kobj);
1061
1062 /*
1063 * We need to make sure that the underlying kobj is
1064 * actually not referenced anymore by anybody before we
1065 * proceed with unloading.
1066 */
1067 pr_debug("waiting for dropping of refcount\n");
1068 wait_for_completion(cmp);
1069 pr_debug("wait complete\n");
1070}
1071
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301072static void cpufreq_policy_free(struct cpufreq_policy *policy)
1073{
1074 free_cpumask_var(policy->related_cpus);
1075 free_cpumask_var(policy->cpus);
1076 kfree(policy);
1077}
1078
Srivatsa S. Bhat0d66b912013-09-12 01:42:59 +05301079static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu)
1080{
Srivatsa S. Bhat99ec8992013-09-12 17:29:09 +05301081 if (WARN_ON(cpu == policy->cpu))
Srivatsa S. Bhatcb38ed52013-09-12 01:43:42 +05301082 return;
1083
viresh kumarad7722d2013-10-18 19:10:15 +05301084 down_write(&policy->rwsem);
Viresh Kumar8efd5762013-09-17 10:22:11 +05301085
Srivatsa S. Bhat0d66b912013-09-12 01:42:59 +05301086 policy->last_cpu = policy->cpu;
1087 policy->cpu = cpu;
1088
viresh kumarad7722d2013-10-18 19:10:15 +05301089 up_write(&policy->rwsem);
Viresh Kumar8efd5762013-09-17 10:22:11 +05301090
Srivatsa S. Bhat0d66b912013-09-12 01:42:59 +05301091 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
1092 CPUFREQ_UPDATE_POLICY_CPU, policy);
1093}
1094
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301095static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096{
Viresh Kumarfcf80582013-01-29 14:39:08 +00001097 unsigned int j, cpu = dev->id;
Viresh Kumar65922462013-02-07 10:56:03 +05301098 int ret = -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099 struct cpufreq_policy *policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001100 unsigned long flags;
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301101 bool recover_policy = cpufreq_suspended;
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05001102#ifdef CONFIG_HOTPLUG_CPU
Viresh Kumar1b274292013-08-20 12:08:26 +05301103 struct cpufreq_policy *tpolicy;
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05001104#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105
Ashok Rajc32b6b82005-10-30 14:59:54 -08001106 if (cpu_is_offline(cpu))
1107 return 0;
1108
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02001109 pr_debug("adding CPU %u\n", cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110
1111#ifdef CONFIG_SMP
1112 /* check whether a different CPU already registered this
1113 * CPU because it is in the same boat. */
1114 policy = cpufreq_cpu_get(cpu);
1115 if (unlikely(policy)) {
Dave Jones8ff69732006-03-05 03:37:23 -05001116 cpufreq_cpu_put(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117 return 0;
1118 }
Li Zhong5025d622013-08-21 01:31:08 +02001119#endif
Viresh Kumarfcf80582013-01-29 14:39:08 +00001120
Viresh Kumar6eed9402013-08-06 22:53:11 +05301121 if (!down_read_trylock(&cpufreq_rwsem))
1122 return 0;
1123
Viresh Kumarfcf80582013-01-29 14:39:08 +00001124#ifdef CONFIG_HOTPLUG_CPU
1125 /* Check if this cpu was hot-unplugged earlier and has siblings */
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00001126 read_lock_irqsave(&cpufreq_driver_lock, flags);
Viresh Kumar1b274292013-08-20 12:08:26 +05301127 list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) {
1128 if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) {
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00001129 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
Viresh Kumar42f921a2013-12-20 21:26:02 +05301130 ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev);
Viresh Kumar6eed9402013-08-06 22:53:11 +05301131 up_read(&cpufreq_rwsem);
1132 return ret;
Viresh Kumar2eaa3e22013-02-07 10:55:00 +05301133 }
Viresh Kumarfcf80582013-01-29 14:39:08 +00001134 }
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00001135 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
Viresh Kumarfcf80582013-01-29 14:39:08 +00001136#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137
Rafael J. Wysocki72368d12013-12-27 01:07:11 +01001138 /*
1139 * Restore the saved policy when doing light-weight init and fall back
1140 * to the full init if that fails.
1141 */
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301142 policy = recover_policy ? cpufreq_policy_restore(cpu) : NULL;
Rafael J. Wysocki72368d12013-12-27 01:07:11 +01001143 if (!policy) {
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301144 recover_policy = false;
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301145 policy = cpufreq_policy_alloc();
Rafael J. Wysocki72368d12013-12-27 01:07:11 +01001146 if (!policy)
1147 goto nomem_out;
1148 }
Srivatsa S. Bhat0d66b912013-09-12 01:42:59 +05301149
1150 /*
1151 * In the resume path, since we restore a saved policy, the assignment
1152 * to policy->cpu is like an update of the existing policy, rather than
1153 * the creation of a brand new one. So we need to perform this update
1154 * by invoking update_policy_cpu().
1155 */
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301156 if (recover_policy && cpu != policy->cpu)
Srivatsa S. Bhat0d66b912013-09-12 01:42:59 +05301157 update_policy_cpu(policy, cpu);
1158 else
1159 policy->cpu = cpu;
1160
Rusty Russell835481d2009-01-04 05:18:06 -08001161 cpumask_copy(policy->cpus, cpumask_of(cpu));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162
Linus Torvalds1da177e2005-04-16 15:20:36 -07001163 init_completion(&policy->kobj_unregister);
David Howells65f27f32006-11-22 14:55:48 +00001164 INIT_WORK(&policy->update, handle_update);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001165
1166 /* call driver. From then on the cpufreq must be able
1167 * to accept all calls to ->verify and ->setpolicy for this CPU
1168 */
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001169 ret = cpufreq_driver->init(policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170 if (ret) {
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02001171 pr_debug("initialization failed\n");
Viresh Kumar2eaa3e22013-02-07 10:55:00 +05301172 goto err_set_policy_cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173 }
Viresh Kumar643ae6e2013-01-12 05:14:38 +00001174
Viresh Kumar5a7e56a2014-03-04 11:44:00 +08001175 /* related cpus should atleast have policy->cpus */
1176 cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus);
1177
1178 /*
1179 * affected cpus must always be the one, which are online. We aren't
1180 * managing offline cpus here.
1181 */
1182 cpumask_and(policy->cpus, policy->cpus, cpu_online_mask);
1183
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301184 if (!recover_policy) {
Viresh Kumar5a7e56a2014-03-04 11:44:00 +08001185 policy->user_policy.min = policy->min;
1186 policy->user_policy.max = policy->max;
1187 }
1188
Viresh Kumar4e97b632014-03-04 11:44:01 +08001189 down_write(&policy->rwsem);
Viresh Kumar652ed952014-01-09 20:38:43 +05301190 write_lock_irqsave(&cpufreq_driver_lock, flags);
1191 for_each_cpu(j, policy->cpus)
1192 per_cpu(cpufreq_cpu_data, j) = policy;
1193 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
1194
Rafael J. Wysocki2ed99e32014-03-12 21:49:33 +01001195 if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
Viresh Kumarda60ce92013-10-03 20:28:30 +05301196 policy->cur = cpufreq_driver->get(policy->cpu);
1197 if (!policy->cur) {
1198 pr_err("%s: ->get() failed\n", __func__);
1199 goto err_get_freq;
1200 }
1201 }
1202
Viresh Kumard3916692013-12-03 11:20:46 +05301203 /*
1204 * Sometimes boot loaders set CPU frequency to a value outside of
1205 * frequency table present with cpufreq core. In such cases CPU might be
1206 * unstable if it has to run on that frequency for long duration of time
1207 * and so its better to set it to a frequency which is specified in
1208 * freq-table. This also makes cpufreq stats inconsistent as
1209 * cpufreq-stats would fail to register because current frequency of CPU
1210 * isn't found in freq-table.
1211 *
1212 * Because we don't want this change to effect boot process badly, we go
1213 * for the next freq which is >= policy->cur ('cur' must be set by now,
1214 * otherwise we will end up setting freq to lowest of the table as 'cur'
1215 * is initialized to zero).
1216 *
1217 * We are passing target-freq as "policy->cur - 1" otherwise
1218 * __cpufreq_driver_target() would simply fail, as policy->cur will be
1219 * equal to target-freq.
1220 */
1221 if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK)
1222 && has_target()) {
1223 /* Are we running at unknown frequency ? */
1224 ret = cpufreq_frequency_table_get_index(policy, policy->cur);
1225 if (ret == -EINVAL) {
1226 /* Warn user and fix it */
1227 pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n",
1228 __func__, policy->cpu, policy->cur);
1229 ret = __cpufreq_driver_target(policy, policy->cur - 1,
1230 CPUFREQ_RELATION_L);
1231
1232 /*
1233 * Reaching here after boot in a few seconds may not
1234 * mean that system will remain stable at "unknown"
1235 * frequency for longer duration. Hence, a BUG_ON().
1236 */
1237 BUG_ON(ret);
1238 pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n",
1239 __func__, policy->cpu, policy->cur);
1240 }
1241 }
1242
Thomas Renningera1531ac2008-07-29 22:32:58 -07001243 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
1244 CPUFREQ_START, policy);
1245
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301246 if (!recover_policy) {
Viresh Kumar308b60e2013-07-31 14:35:14 +02001247 ret = cpufreq_add_dev_interface(policy, dev);
Srivatsa S. Bhata82fab22013-07-30 04:24:49 +05301248 if (ret)
1249 goto err_out_unregister;
Viresh Kumarfcd7af92014-01-07 07:10:10 +05301250 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
1251 CPUFREQ_CREATE_POLICY, policy);
Srivatsa S. Bhata82fab22013-07-30 04:24:49 +05301252 }
Dave Jones8ff69732006-03-05 03:37:23 -05001253
Viresh Kumar9515f4d2013-08-20 12:08:23 +05301254 write_lock_irqsave(&cpufreq_driver_lock, flags);
1255 list_add(&policy->policy_list, &cpufreq_policy_list);
1256 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
1257
Srivatsa S. Bhate18f1682013-07-30 04:24:23 +05301258 cpufreq_init_policy(policy);
1259
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301260 if (!recover_policy) {
Viresh Kumar08fd8c1c2013-12-24 07:11:01 +05301261 policy->user_policy.policy = policy->policy;
1262 policy->user_policy.governor = policy->governor;
1263 }
Viresh Kumar4e97b632014-03-04 11:44:01 +08001264 up_write(&policy->rwsem);
Viresh Kumar08fd8c1c2013-12-24 07:11:01 +05301265
Greg Kroah-Hartman038c5b32007-12-17 15:54:39 -04001266 kobject_uevent(&policy->kobj, KOBJ_ADD);
Viresh Kumar6eed9402013-08-06 22:53:11 +05301267 up_read(&cpufreq_rwsem);
1268
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02001269 pr_debug("initialization complete\n");
Dave Jones87c32272006-03-29 01:48:37 -05001270
Linus Torvalds1da177e2005-04-16 15:20:36 -07001271 return 0;
1272
Linus Torvalds1da177e2005-04-16 15:20:36 -07001273err_out_unregister:
Viresh Kumar652ed952014-01-09 20:38:43 +05301274err_get_freq:
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00001275 write_lock_irqsave(&cpufreq_driver_lock, flags);
Viresh Kumar474deff2013-08-20 12:08:25 +05301276 for_each_cpu(j, policy->cpus)
Mike Travis7a6aedf2008-03-25 15:06:53 -07001277 per_cpu(cpufreq_cpu_data, j) = NULL;
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00001278 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279
Viresh Kumarda60ce92013-10-03 20:28:30 +05301280 if (cpufreq_driver->exit)
1281 cpufreq_driver->exit(policy);
Viresh Kumar2eaa3e22013-02-07 10:55:00 +05301282err_set_policy_cpu:
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301283 if (recover_policy) {
Rafael J. Wysocki72368d12013-12-27 01:07:11 +01001284 /* Do not leave stale fallback data behind. */
1285 per_cpu(cpufreq_cpu_data_fallback, cpu) = NULL;
Viresh Kumar42f921a2013-12-20 21:26:02 +05301286 cpufreq_policy_put_kobj(policy);
Rafael J. Wysocki72368d12013-12-27 01:07:11 +01001287 }
Srivatsa S. Bhate9698cc2013-07-30 04:24:11 +05301288 cpufreq_policy_free(policy);
Viresh Kumar42f921a2013-12-20 21:26:02 +05301289
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290nomem_out:
Viresh Kumar6eed9402013-08-06 22:53:11 +05301291 up_read(&cpufreq_rwsem);
1292
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293 return ret;
1294}
1295
Srivatsa S. Bhata82fab22013-07-30 04:24:49 +05301296/**
1297 * cpufreq_add_dev - add a CPU device
1298 *
1299 * Adds the cpufreq interface for a CPU device.
1300 *
1301 * The Oracle says: try running cpufreq registration/unregistration concurrently
1302 * with with cpu hotplugging and all hell will break loose. Tried to clean this
1303 * mess up, but more thorough testing is needed. - Mathieu
1304 */
1305static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
1306{
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301307 return __cpufreq_add_dev(dev, sif);
Srivatsa S. Bhata82fab22013-07-30 04:24:49 +05301308}
1309
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301310static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy,
Viresh Kumar42f921a2013-12-20 21:26:02 +05301311 unsigned int old_cpu)
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301312{
1313 struct device *cpu_dev;
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301314 int ret;
1315
1316 /* first sibling now owns the new sysfs dir */
Viresh Kumar9c8f1ee2013-09-12 17:06:33 +05301317 cpu_dev = get_cpu_device(cpumask_any_but(policy->cpus, old_cpu));
Srivatsa S. Bhata82fab22013-07-30 04:24:49 +05301318
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301319 sysfs_remove_link(&cpu_dev->kobj, "cpufreq");
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301320 ret = kobject_move(&policy->kobj, &cpu_dev->kobj);
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301321 if (ret) {
Joe Perchese837f9b2014-03-11 10:03:00 -07001322 pr_err("%s: Failed to move kobj: %d\n", __func__, ret);
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301323
viresh kumarad7722d2013-10-18 19:10:15 +05301324 down_write(&policy->rwsem);
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301325 cpumask_set_cpu(old_cpu, policy->cpus);
viresh kumarad7722d2013-10-18 19:10:15 +05301326 up_write(&policy->rwsem);
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301327
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301328 ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj,
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301329 "cpufreq");
1330
1331 return -EINVAL;
1332 }
1333
1334 return cpu_dev->id;
1335}
1336
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301337static int __cpufreq_remove_dev_prepare(struct device *dev,
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301338 struct subsys_interface *sif)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001339{
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301340 unsigned int cpu = dev->id, cpus;
Viresh Kumar3de9bde2013-08-06 22:53:13 +05301341 int new_cpu, ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342 unsigned long flags;
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301343 struct cpufreq_policy *policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001344
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001345 pr_debug("%s: unregistering CPU %u\n", __func__, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00001347 write_lock_irqsave(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001348
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301349 policy = per_cpu(cpufreq_cpu_data, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301351 /* Save the policy somewhere when doing a light-weight tear-down */
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301352 if (cpufreq_suspended)
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301353 per_cpu(cpufreq_cpu_data_fallback, cpu) = policy;
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301354
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00001355 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301357 if (!policy) {
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001358 pr_debug("%s: No cpu_data found\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001359 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001361
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301362 if (has_target()) {
Viresh Kumar3de9bde2013-08-06 22:53:13 +05301363 ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
1364 if (ret) {
1365 pr_err("%s: Failed to stop governor\n", __func__);
1366 return ret;
1367 }
1368 }
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001369
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001370 if (!cpufreq_driver->setpolicy)
Dirk Brandewiefa69e332013-02-06 09:02:11 -08001371 strncpy(per_cpu(cpufreq_cpu_governor, cpu),
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301372 policy->governor->name, CPUFREQ_NAME_LEN);
Jacob Shin27ecddc2011-04-27 13:32:11 -05001373
viresh kumarad7722d2013-10-18 19:10:15 +05301374 down_read(&policy->rwsem);
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301375 cpus = cpumask_weight(policy->cpus);
viresh kumarad7722d2013-10-18 19:10:15 +05301376 up_read(&policy->rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001377
Srivatsa S. Bhat61173f22013-09-12 01:43:25 +05301378 if (cpu != policy->cpu) {
viresh kumar6964d912014-02-17 14:52:11 +05301379 sysfs_remove_link(&dev->kobj, "cpufreq");
Viresh Kumar73bf0fc2013-02-05 22:21:14 +01001380 } else if (cpus > 1) {
Viresh Kumar42f921a2013-12-20 21:26:02 +05301381 new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu);
Srivatsa S. Bhatf9ba6802013-07-30 04:24:36 +05301382 if (new_cpu >= 0) {
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301383 update_policy_cpu(policy, new_cpu);
Srivatsa S. Bhata82fab22013-07-30 04:24:49 +05301384
Stratos Karafotisbda9f552014-03-20 01:25:13 +02001385 if (!cpufreq_suspended)
Viresh Kumar75949c92013-10-02 14:13:13 +05301386 pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07001387 __func__, new_cpu, cpu);
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001388 }
Dirk Brandewie367dc4a2014-03-19 08:45:53 -07001389 } else if (cpufreq_driver->stop_cpu && cpufreq_driver->setpolicy) {
1390 cpufreq_driver->stop_cpu(policy);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001391 }
Venki Pallipadiec282972007-03-26 12:03:19 -07001392
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301393 return 0;
1394}
1395
1396static int __cpufreq_remove_dev_finish(struct device *dev,
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301397 struct subsys_interface *sif)
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301398{
1399 unsigned int cpu = dev->id, cpus;
1400 int ret;
1401 unsigned long flags;
1402 struct cpufreq_policy *policy;
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301403
1404 read_lock_irqsave(&cpufreq_driver_lock, flags);
1405 policy = per_cpu(cpufreq_cpu_data, cpu);
1406 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
1407
1408 if (!policy) {
1409 pr_debug("%s: No cpu_data found\n", __func__);
1410 return -EINVAL;
1411 }
1412
viresh kumarad7722d2013-10-18 19:10:15 +05301413 down_write(&policy->rwsem);
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301414 cpus = cpumask_weight(policy->cpus);
Viresh Kumar9c8f1ee2013-09-12 17:06:33 +05301415
1416 if (cpus > 1)
1417 cpumask_clear_cpu(cpu, policy->cpus);
viresh kumarad7722d2013-10-18 19:10:15 +05301418 up_write(&policy->rwsem);
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301419
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001420 /* If cpu is last user of policy, free policy */
1421 if (cpus == 1) {
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301422 if (has_target()) {
Viresh Kumar3de9bde2013-08-06 22:53:13 +05301423 ret = __cpufreq_governor(policy,
1424 CPUFREQ_GOV_POLICY_EXIT);
1425 if (ret) {
1426 pr_err("%s: Failed to exit governor\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07001427 __func__);
Viresh Kumar3de9bde2013-08-06 22:53:13 +05301428 return ret;
1429 }
Viresh Kumaredab2fb2013-08-20 12:08:22 +05301430 }
Rafael J. Wysocki2a998592013-07-30 00:32:00 +02001431
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301432 if (!cpufreq_suspended)
Viresh Kumar42f921a2013-12-20 21:26:02 +05301433 cpufreq_policy_put_kobj(policy);
Srivatsa S. Bhat84148092013-07-30 04:25:10 +05301434
1435 /*
1436 * Perform the ->exit() even during light-weight tear-down,
1437 * since this is a core component, and is essential for the
1438 * subsequent light-weight ->init() to succeed.
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001439 */
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001440 if (cpufreq_driver->exit)
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301441 cpufreq_driver->exit(policy);
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001442
Viresh Kumar9515f4d2013-08-20 12:08:23 +05301443 /* Remove policy from list of active policies */
1444 write_lock_irqsave(&cpufreq_driver_lock, flags);
1445 list_del(&policy->policy_list);
1446 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
1447
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301448 if (!cpufreq_suspended)
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301449 cpufreq_policy_free(policy);
Stratos Karafotise5c87b72014-03-19 23:29:17 +02001450 } else if (has_target()) {
1451 ret = __cpufreq_governor(policy, CPUFREQ_GOV_START);
1452 if (!ret)
1453 ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
1454
1455 if (ret) {
1456 pr_err("%s: Failed to start governor\n", __func__);
1457 return ret;
Rafael J. Wysocki2a998592013-07-30 00:32:00 +02001458 }
Viresh Kumarb8eed8a2013-01-14 13:23:03 +00001459 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001460
Viresh Kumar474deff2013-08-20 12:08:25 +05301461 per_cpu(cpufreq_cpu_data, cpu) = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001462 return 0;
1463}
1464
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301465/**
Viresh Kumar27a862e2013-10-02 14:13:14 +05301466 * cpufreq_remove_dev - remove a CPU device
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301467 *
1468 * Removes the cpufreq interface for a CPU device.
Srivatsa S. Bhatcedb70a2013-09-07 01:23:09 +05301469 */
Kay Sievers8a25a2f2011-12-21 14:29:42 -08001470static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001471{
Kay Sievers8a25a2f2011-12-21 14:29:42 -08001472 unsigned int cpu = dev->id;
Viresh Kumar27a862e2013-10-02 14:13:14 +05301473 int ret;
Venki Pallipadiec282972007-03-26 12:03:19 -07001474
1475 if (cpu_is_offline(cpu))
1476 return 0;
1477
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301478 ret = __cpufreq_remove_dev_prepare(dev, sif);
Viresh Kumar27a862e2013-10-02 14:13:14 +05301479
1480 if (!ret)
Viresh Kumar96bbbe42014-03-10 14:53:35 +05301481 ret = __cpufreq_remove_dev_finish(dev, sif);
Viresh Kumar27a862e2013-10-02 14:13:14 +05301482
1483 return ret;
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001484}
1485
David Howells65f27f32006-11-22 14:55:48 +00001486static void handle_update(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487{
David Howells65f27f32006-11-22 14:55:48 +00001488 struct cpufreq_policy *policy =
1489 container_of(work, struct cpufreq_policy, update);
1490 unsigned int cpu = policy->cpu;
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02001491 pr_debug("handle_update for cpu %u called\n", cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492 cpufreq_update_policy(cpu);
1493}
1494
1495/**
Viresh Kumarbb176f72013-06-19 14:19:33 +05301496 * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're
1497 * in deep trouble.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 * @cpu: cpu number
1499 * @old_freq: CPU frequency the kernel thinks the CPU runs at
1500 * @new_freq: CPU frequency the CPU actually runs at
1501 *
Dave Jones29464f22009-01-18 01:37:11 -05001502 * We adjust to current frequency first, and need to clean up later.
1503 * So either call to cpufreq_update_policy() or schedule handle_update()).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504 */
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301505static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq,
1506 unsigned int new_freq)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001507{
Viresh Kumarb43a7ff2013-03-24 11:56:43 +05301508 struct cpufreq_policy *policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001509 struct cpufreq_freqs freqs;
Viresh Kumarb43a7ff2013-03-24 11:56:43 +05301510 unsigned long flags;
1511
Joe Perchese837f9b2014-03-11 10:03:00 -07001512 pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n",
1513 old_freq, new_freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515 freqs.old = old_freq;
1516 freqs.new = new_freq;
Viresh Kumarb43a7ff2013-03-24 11:56:43 +05301517
1518 read_lock_irqsave(&cpufreq_driver_lock, flags);
1519 policy = per_cpu(cpufreq_cpu_data, cpu);
1520 read_unlock_irqrestore(&cpufreq_driver_lock, flags);
1521
Viresh Kumar8fec0512014-03-24 13:35:45 +05301522 cpufreq_freq_transition_begin(policy, &freqs);
1523 cpufreq_freq_transition_end(policy, &freqs, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001524}
1525
Dave Jones32ee8c32006-02-28 00:43:23 -05001526/**
Dhaval Giani4ab70df2006-12-13 14:49:15 +05301527 * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001528 * @cpu: CPU number
1529 *
1530 * This is the last known freq, without actually getting it from the driver.
1531 * Return value will be same as what is shown in scaling_cur_freq in sysfs.
1532 */
1533unsigned int cpufreq_quick_get(unsigned int cpu)
1534{
Dirk Brandewie9e21ba82013-02-06 09:02:08 -08001535 struct cpufreq_policy *policy;
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301536 unsigned int ret_freq = 0;
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001537
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001538 if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get)
1539 return cpufreq_driver->get(cpu);
Dirk Brandewie9e21ba82013-02-06 09:02:08 -08001540
1541 policy = cpufreq_cpu_get(cpu);
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001542 if (policy) {
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301543 ret_freq = policy->cur;
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001544 cpufreq_cpu_put(policy);
1545 }
1546
Dave Jones4d34a672008-02-07 16:33:49 -05001547 return ret_freq;
Venkatesh Pallipadi95235ca2005-12-02 10:43:20 -08001548}
1549EXPORT_SYMBOL(cpufreq_quick_get);
1550
Jesse Barnes3d737102011-06-28 10:59:12 -07001551/**
1552 * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU
1553 * @cpu: CPU number
1554 *
1555 * Just return the max possible frequency for a given CPU.
1556 */
1557unsigned int cpufreq_quick_get_max(unsigned int cpu)
1558{
1559 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
1560 unsigned int ret_freq = 0;
1561
1562 if (policy) {
1563 ret_freq = policy->max;
1564 cpufreq_cpu_put(policy);
1565 }
1566
1567 return ret_freq;
1568}
1569EXPORT_SYMBOL(cpufreq_quick_get_max);
1570
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001571static unsigned int __cpufreq_get(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572{
Mike Travis7a6aedf2008-03-25 15:06:53 -07001573 struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301574 unsigned int ret_freq = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001575
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001576 if (!cpufreq_driver->get)
Dave Jones4d34a672008-02-07 16:33:49 -05001577 return ret_freq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001579 ret_freq = cpufreq_driver->get(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001580
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301581 if (ret_freq && policy->cur &&
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001582 !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301583 /* verify no discrepancy between actual and
1584 saved value exists */
1585 if (unlikely(ret_freq != policy->cur)) {
1586 cpufreq_out_of_sync(cpu, policy->cur, ret_freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587 schedule_work(&policy->update);
1588 }
1589 }
1590
Dave Jones4d34a672008-02-07 16:33:49 -05001591 return ret_freq;
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001592}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001594/**
1595 * cpufreq_get - get the current CPU frequency (in kHz)
1596 * @cpu: CPU number
1597 *
1598 * Get the CPU current (static) CPU frequency
1599 */
1600unsigned int cpufreq_get(unsigned int cpu)
1601{
Aaron Plattner999976e2014-03-04 12:42:15 -08001602 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001603 unsigned int ret_freq = 0;
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08001604
Aaron Plattner999976e2014-03-04 12:42:15 -08001605 if (policy) {
1606 down_read(&policy->rwsem);
1607 ret_freq = __cpufreq_get(cpu);
1608 up_read(&policy->rwsem);
Viresh Kumar26ca8692013-09-20 22:37:31 +05301609
Aaron Plattner999976e2014-03-04 12:42:15 -08001610 cpufreq_cpu_put(policy);
1611 }
Viresh Kumar6eed9402013-08-06 22:53:11 +05301612
Dave Jones4d34a672008-02-07 16:33:49 -05001613 return ret_freq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001614}
1615EXPORT_SYMBOL(cpufreq_get);
1616
Kay Sievers8a25a2f2011-12-21 14:29:42 -08001617static struct subsys_interface cpufreq_interface = {
1618 .name = "cpufreq",
1619 .subsys = &cpu_subsys,
1620 .add_dev = cpufreq_add_dev,
1621 .remove_dev = cpufreq_remove_dev,
Rafael J. Wysockie00e56d2011-03-23 22:16:32 +01001622};
1623
Viresh Kumare28867e2014-03-04 11:00:27 +08001624/*
1625 * In case platform wants some specific frequency to be configured
1626 * during suspend..
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001627 */
Viresh Kumare28867e2014-03-04 11:00:27 +08001628int cpufreq_generic_suspend(struct cpufreq_policy *policy)
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001629{
Viresh Kumare28867e2014-03-04 11:00:27 +08001630 int ret;
Dave Jones4bc5d342009-08-04 14:03:25 -04001631
Viresh Kumare28867e2014-03-04 11:00:27 +08001632 if (!policy->suspend_freq) {
1633 pr_err("%s: suspend_freq can't be zero\n", __func__);
1634 return -EINVAL;
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001635 }
1636
Viresh Kumare28867e2014-03-04 11:00:27 +08001637 pr_debug("%s: Setting suspend-freq: %u\n", __func__,
1638 policy->suspend_freq);
1639
1640 ret = __cpufreq_driver_target(policy, policy->suspend_freq,
1641 CPUFREQ_RELATION_H);
1642 if (ret)
1643 pr_err("%s: unable to set suspend-freq: %u. err: %d\n",
1644 __func__, policy->suspend_freq, ret);
1645
Dave Jonesc9060492008-02-07 16:32:18 -05001646 return ret;
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001647}
Viresh Kumare28867e2014-03-04 11:00:27 +08001648EXPORT_SYMBOL(cpufreq_generic_suspend);
Benjamin Herrenschmidt42d4dc32005-04-29 07:40:12 -07001649
1650/**
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001651 * cpufreq_suspend() - Suspend CPUFreq governors
Linus Torvalds1da177e2005-04-16 15:20:36 -07001652 *
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001653 * Called during system wide Suspend/Hibernate cycles for suspending governors
1654 * as some platforms can't change frequency after this point in suspend cycle.
1655 * Because some of the devices (like: i2c, regulators, etc) they use for
1656 * changing frequency are suspended quickly after this point.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 */
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001658void cpufreq_suspend(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659{
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05301660 struct cpufreq_policy *policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001662 if (!cpufreq_driver)
Rafael J. Wysockie00e56d2011-03-23 22:16:32 +01001663 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001665 if (!has_target())
1666 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001667
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001668 pr_debug("%s: Suspending Governors\n", __func__);
1669
1670 list_for_each_entry(policy, &cpufreq_policy_list, policy_list) {
1671 if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP))
1672 pr_err("%s: Failed to stop governor for policy: %p\n",
1673 __func__, policy);
1674 else if (cpufreq_driver->suspend
1675 && cpufreq_driver->suspend(policy))
1676 pr_err("%s: Failed to suspend driver: %p\n", __func__,
1677 policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001678 }
1679
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001680 cpufreq_suspended = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001681}
1682
Linus Torvalds1da177e2005-04-16 15:20:36 -07001683/**
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001684 * cpufreq_resume() - Resume CPUFreq governors
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685 *
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001686 * Called during system wide Suspend/Hibernate cycle for resuming governors that
1687 * are suspended with cpufreq_suspend().
Linus Torvalds1da177e2005-04-16 15:20:36 -07001688 */
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001689void cpufreq_resume(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001691 struct cpufreq_policy *policy;
1692
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001693 if (!cpufreq_driver)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001694 return;
1695
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001696 if (!has_target())
1697 return;
1698
1699 pr_debug("%s: Resuming Governors\n", __func__);
1700
1701 cpufreq_suspended = false;
1702
1703 list_for_each_entry(policy, &cpufreq_policy_list, policy_list) {
Viresh Kumar0c5aa402014-03-24 12:30:29 +05301704 if (cpufreq_driver->resume && cpufreq_driver->resume(policy))
1705 pr_err("%s: Failed to resume driver: %p\n", __func__,
1706 policy);
1707 else if (__cpufreq_governor(policy, CPUFREQ_GOV_START)
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001708 || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS))
1709 pr_err("%s: Failed to start governor for policy: %p\n",
1710 __func__, policy);
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001711
1712 /*
1713 * schedule call cpufreq_update_policy() for boot CPU, i.e. last
1714 * policy in list. It will verify that the current freq is in
1715 * sync with what we believe it to be.
1716 */
1717 if (list_is_last(&policy->policy_list, &cpufreq_policy_list))
1718 schedule_work(&policy->update);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001719 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001720}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001721
Borislav Petkov9d950462013-01-20 10:24:28 +00001722/**
1723 * cpufreq_get_current_driver - return current driver's name
1724 *
1725 * Return the name string of the currently loaded cpufreq driver
1726 * or NULL, if none.
1727 */
1728const char *cpufreq_get_current_driver(void)
1729{
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001730 if (cpufreq_driver)
1731 return cpufreq_driver->name;
1732
1733 return NULL;
Borislav Petkov9d950462013-01-20 10:24:28 +00001734}
1735EXPORT_SYMBOL_GPL(cpufreq_get_current_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001736
1737/*********************************************************************
1738 * NOTIFIER LISTS INTERFACE *
1739 *********************************************************************/
1740
1741/**
1742 * cpufreq_register_notifier - register a driver with cpufreq
1743 * @nb: notifier function to register
1744 * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
1745 *
Dave Jones32ee8c32006-02-28 00:43:23 -05001746 * Add a driver to one of two lists: either a list of drivers that
Linus Torvalds1da177e2005-04-16 15:20:36 -07001747 * are notified about clock rate changes (once before and once after
1748 * the transition), or a list of drivers that are notified about
1749 * changes in cpufreq policy.
1750 *
1751 * This function may sleep, and has the same return conditions as
Alan Sterne041c682006-03-27 01:16:30 -08001752 * blocking_notifier_chain_register.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001753 */
1754int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
1755{
1756 int ret;
1757
Dirk Brandewied5aaffa2013-01-17 16:22:21 +00001758 if (cpufreq_disabled())
1759 return -EINVAL;
1760
Cesar Eduardo Barros74212ca2008-02-16 08:41:24 -02001761 WARN_ON(!init_cpufreq_transition_notifier_list_called);
1762
Linus Torvalds1da177e2005-04-16 15:20:36 -07001763 switch (list) {
1764 case CPUFREQ_TRANSITION_NOTIFIER:
Alan Sternb4dfdbb2006-10-04 02:17:06 -07001765 ret = srcu_notifier_chain_register(
Alan Sterne041c682006-03-27 01:16:30 -08001766 &cpufreq_transition_notifier_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001767 break;
1768 case CPUFREQ_POLICY_NOTIFIER:
Alan Sterne041c682006-03-27 01:16:30 -08001769 ret = blocking_notifier_chain_register(
1770 &cpufreq_policy_notifier_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771 break;
1772 default:
1773 ret = -EINVAL;
1774 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001775
1776 return ret;
1777}
1778EXPORT_SYMBOL(cpufreq_register_notifier);
1779
Linus Torvalds1da177e2005-04-16 15:20:36 -07001780/**
1781 * cpufreq_unregister_notifier - unregister a driver with cpufreq
1782 * @nb: notifier block to be unregistered
Viresh Kumarbb176f72013-06-19 14:19:33 +05301783 * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
Linus Torvalds1da177e2005-04-16 15:20:36 -07001784 *
1785 * Remove a driver from the CPU frequency notifier list.
1786 *
1787 * This function may sleep, and has the same return conditions as
Alan Sterne041c682006-03-27 01:16:30 -08001788 * blocking_notifier_chain_unregister.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001789 */
1790int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
1791{
1792 int ret;
1793
Dirk Brandewied5aaffa2013-01-17 16:22:21 +00001794 if (cpufreq_disabled())
1795 return -EINVAL;
1796
Linus Torvalds1da177e2005-04-16 15:20:36 -07001797 switch (list) {
1798 case CPUFREQ_TRANSITION_NOTIFIER:
Alan Sternb4dfdbb2006-10-04 02:17:06 -07001799 ret = srcu_notifier_chain_unregister(
Alan Sterne041c682006-03-27 01:16:30 -08001800 &cpufreq_transition_notifier_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001801 break;
1802 case CPUFREQ_POLICY_NOTIFIER:
Alan Sterne041c682006-03-27 01:16:30 -08001803 ret = blocking_notifier_chain_unregister(
1804 &cpufreq_policy_notifier_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001805 break;
1806 default:
1807 ret = -EINVAL;
1808 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001809
1810 return ret;
1811}
1812EXPORT_SYMBOL(cpufreq_unregister_notifier);
1813
1814
1815/*********************************************************************
1816 * GOVERNORS *
1817 *********************************************************************/
1818
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05301819/* Must set freqs->new to intermediate frequency */
1820static int __target_intermediate(struct cpufreq_policy *policy,
1821 struct cpufreq_freqs *freqs, int index)
1822{
1823 int ret;
1824
1825 freqs->new = cpufreq_driver->get_intermediate(policy, index);
1826
1827 /* We don't need to switch to intermediate freq */
1828 if (!freqs->new)
1829 return 0;
1830
1831 pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n",
1832 __func__, policy->cpu, freqs->old, freqs->new);
1833
1834 cpufreq_freq_transition_begin(policy, freqs);
1835 ret = cpufreq_driver->target_intermediate(policy, index);
1836 cpufreq_freq_transition_end(policy, freqs, ret);
1837
1838 if (ret)
1839 pr_err("%s: Failed to change to intermediate frequency: %d\n",
1840 __func__, ret);
1841
1842 return ret;
1843}
1844
Viresh Kumar8d657752014-05-21 14:29:29 +05301845static int __target_index(struct cpufreq_policy *policy,
1846 struct cpufreq_frequency_table *freq_table, int index)
1847{
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05301848 struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0};
1849 unsigned int intermediate_freq = 0;
Viresh Kumar8d657752014-05-21 14:29:29 +05301850 int retval = -EINVAL;
1851 bool notify;
1852
1853 notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION);
Viresh Kumar8d657752014-05-21 14:29:29 +05301854 if (notify) {
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05301855 /* Handle switching to intermediate frequency */
1856 if (cpufreq_driver->get_intermediate) {
1857 retval = __target_intermediate(policy, &freqs, index);
1858 if (retval)
1859 return retval;
Viresh Kumar8d657752014-05-21 14:29:29 +05301860
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05301861 intermediate_freq = freqs.new;
1862 /* Set old freq to intermediate */
1863 if (intermediate_freq)
1864 freqs.old = freqs.new;
1865 }
1866
1867 freqs.new = freq_table[index].frequency;
Viresh Kumar8d657752014-05-21 14:29:29 +05301868 pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n",
1869 __func__, policy->cpu, freqs.old, freqs.new);
1870
1871 cpufreq_freq_transition_begin(policy, &freqs);
1872 }
1873
1874 retval = cpufreq_driver->target_index(policy, index);
1875 if (retval)
1876 pr_err("%s: Failed to change cpu frequency: %d\n", __func__,
1877 retval);
1878
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05301879 if (notify) {
Viresh Kumar8d657752014-05-21 14:29:29 +05301880 cpufreq_freq_transition_end(policy, &freqs, retval);
1881
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05301882 /*
1883 * Failed after setting to intermediate freq? Driver should have
1884 * reverted back to initial frequency and so should we. Check
1885 * here for intermediate_freq instead of get_intermediate, in
1886 * case we have't switched to intermediate freq at all.
1887 */
1888 if (unlikely(retval && intermediate_freq)) {
1889 freqs.old = intermediate_freq;
1890 freqs.new = policy->restore_freq;
1891 cpufreq_freq_transition_begin(policy, &freqs);
1892 cpufreq_freq_transition_end(policy, &freqs, 0);
1893 }
1894 }
1895
Viresh Kumar8d657752014-05-21 14:29:29 +05301896 return retval;
1897}
1898
Linus Torvalds1da177e2005-04-16 15:20:36 -07001899int __cpufreq_driver_target(struct cpufreq_policy *policy,
1900 unsigned int target_freq,
1901 unsigned int relation)
1902{
Viresh Kumar72499242012-10-31 01:28:21 +01001903 unsigned int old_target_freq = target_freq;
Viresh Kumar8d657752014-05-21 14:29:29 +05301904 int retval = -EINVAL;
Ashok Rajc32b6b82005-10-30 14:59:54 -08001905
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04001906 if (cpufreq_disabled())
1907 return -ENODEV;
1908
Viresh Kumar72499242012-10-31 01:28:21 +01001909 /* Make sure that target_freq is within supported range */
1910 if (target_freq > policy->max)
1911 target_freq = policy->max;
1912 if (target_freq < policy->min)
1913 target_freq = policy->min;
1914
1915 pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07001916 policy->cpu, target_freq, relation, old_target_freq);
Viresh Kumar5a1c0222012-10-31 01:28:15 +01001917
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301918 /*
1919 * This might look like a redundant call as we are checking it again
1920 * after finding index. But it is left intentionally for cases where
1921 * exactly same freq is called again and so we can save on few function
1922 * calls.
1923 */
Viresh Kumar5a1c0222012-10-31 01:28:15 +01001924 if (target_freq == policy->cur)
1925 return 0;
1926
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05301927 /* Save last value to restore later on errors */
1928 policy->restore_freq = policy->cur;
1929
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02001930 if (cpufreq_driver->target)
1931 retval = cpufreq_driver->target(policy, target_freq, relation);
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301932 else if (cpufreq_driver->target_index) {
1933 struct cpufreq_frequency_table *freq_table;
1934 int index;
Ashok Raj90d45d12005-11-08 21:34:24 -08001935
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301936 freq_table = cpufreq_frequency_get_table(policy->cpu);
1937 if (unlikely(!freq_table)) {
1938 pr_err("%s: Unable to find freq_table\n", __func__);
1939 goto out;
1940 }
1941
1942 retval = cpufreq_frequency_table_target(policy, freq_table,
1943 target_freq, relation, &index);
1944 if (unlikely(retval)) {
1945 pr_err("%s: Unable to find matching freq\n", __func__);
1946 goto out;
1947 }
1948
Viresh Kumard4019f02013-08-14 19:38:24 +05301949 if (freq_table[index].frequency == policy->cur) {
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301950 retval = 0;
Viresh Kumard4019f02013-08-14 19:38:24 +05301951 goto out;
1952 }
1953
Viresh Kumar8d657752014-05-21 14:29:29 +05301954 retval = __target_index(policy, freq_table, index);
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05301955 }
1956
1957out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001958 return retval;
1959}
1960EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
1961
Linus Torvalds1da177e2005-04-16 15:20:36 -07001962int cpufreq_driver_target(struct cpufreq_policy *policy,
1963 unsigned int target_freq,
1964 unsigned int relation)
1965{
Julia Lawallf1829e42008-07-25 22:44:53 +02001966 int ret = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967
viresh kumarad7722d2013-10-18 19:10:15 +05301968 down_write(&policy->rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001969
1970 ret = __cpufreq_driver_target(policy, target_freq, relation);
1971
viresh kumarad7722d2013-10-18 19:10:15 +05301972 up_write(&policy->rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001973
Linus Torvalds1da177e2005-04-16 15:20:36 -07001974 return ret;
1975}
1976EXPORT_SYMBOL_GPL(cpufreq_driver_target);
1977
Arjan van de Ven153d7f32006-07-26 15:40:07 +02001978/*
Arjan van de Ven153d7f32006-07-26 15:40:07 +02001979 * when "event" is CPUFREQ_GOV_LIMITS
1980 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001981
Gautham R Shenoye08f5f52006-10-26 16:20:58 +05301982static int __cpufreq_governor(struct cpufreq_policy *policy,
1983 unsigned int event)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001984{
Dave Jonescc993ca2005-07-28 09:43:56 -07001985 int ret;
Thomas Renninger6afde102007-10-02 13:28:13 -07001986
1987 /* Only must be defined when default governor is known to have latency
1988 restrictions, like e.g. conservative or ondemand.
1989 That this is the case is already ensured in Kconfig
1990 */
1991#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
1992 struct cpufreq_governor *gov = &cpufreq_gov_performance;
1993#else
1994 struct cpufreq_governor *gov = NULL;
1995#endif
Thomas Renninger1c256242007-10-02 13:28:12 -07001996
Viresh Kumar2f0aea92014-03-04 11:00:26 +08001997 /* Don't start any governor operations if we are entering suspend */
1998 if (cpufreq_suspended)
1999 return 0;
2000
Thomas Renninger1c256242007-10-02 13:28:12 -07002001 if (policy->governor->max_transition_latency &&
2002 policy->cpuinfo.transition_latency >
2003 policy->governor->max_transition_latency) {
Thomas Renninger6afde102007-10-02 13:28:13 -07002004 if (!gov)
2005 return -EINVAL;
2006 else {
Joe Perchese837f9b2014-03-11 10:03:00 -07002007 pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n",
2008 policy->governor->name, gov->name);
Thomas Renninger6afde102007-10-02 13:28:13 -07002009 policy->governor = gov;
2010 }
Thomas Renninger1c256242007-10-02 13:28:12 -07002011 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002012
Viresh Kumarfe492f32013-08-06 22:53:10 +05302013 if (event == CPUFREQ_GOV_POLICY_INIT)
2014 if (!try_module_get(policy->governor->owner))
2015 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002016
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002017 pr_debug("__cpufreq_governor for CPU %u, event %u\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07002018 policy->cpu, event);
Xiaoguang Chen95731eb2013-06-19 15:00:07 +08002019
2020 mutex_lock(&cpufreq_governor_lock);
Srivatsa S. Bhat56d07db2013-09-07 01:23:55 +05302021 if ((policy->governor_enabled && event == CPUFREQ_GOV_START)
Viresh Kumarf73d3932013-08-31 17:53:40 +05302022 || (!policy->governor_enabled
2023 && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) {
Xiaoguang Chen95731eb2013-06-19 15:00:07 +08002024 mutex_unlock(&cpufreq_governor_lock);
2025 return -EBUSY;
2026 }
2027
2028 if (event == CPUFREQ_GOV_STOP)
2029 policy->governor_enabled = false;
2030 else if (event == CPUFREQ_GOV_START)
2031 policy->governor_enabled = true;
2032
2033 mutex_unlock(&cpufreq_governor_lock);
2034
Linus Torvalds1da177e2005-04-16 15:20:36 -07002035 ret = policy->governor->governor(policy, event);
2036
Viresh Kumar4d5dcc42013-03-27 15:58:58 +00002037 if (!ret) {
2038 if (event == CPUFREQ_GOV_POLICY_INIT)
2039 policy->governor->initialized++;
2040 else if (event == CPUFREQ_GOV_POLICY_EXIT)
2041 policy->governor->initialized--;
Xiaoguang Chen95731eb2013-06-19 15:00:07 +08002042 } else {
2043 /* Restore original values */
2044 mutex_lock(&cpufreq_governor_lock);
2045 if (event == CPUFREQ_GOV_STOP)
2046 policy->governor_enabled = true;
2047 else if (event == CPUFREQ_GOV_START)
2048 policy->governor_enabled = false;
2049 mutex_unlock(&cpufreq_governor_lock);
Viresh Kumar4d5dcc42013-03-27 15:58:58 +00002050 }
Viresh Kumarb3940582013-02-01 05:42:58 +00002051
Viresh Kumarfe492f32013-08-06 22:53:10 +05302052 if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) ||
2053 ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002054 module_put(policy->governor->owner);
2055
2056 return ret;
2057}
2058
Linus Torvalds1da177e2005-04-16 15:20:36 -07002059int cpufreq_register_governor(struct cpufreq_governor *governor)
2060{
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -07002061 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002062
2063 if (!governor)
2064 return -EINVAL;
2065
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002066 if (cpufreq_disabled())
2067 return -ENODEV;
2068
akpm@osdl.org3fc54d32006-01-13 15:54:22 -08002069 mutex_lock(&cpufreq_governor_mutex);
Dave Jones32ee8c32006-02-28 00:43:23 -05002070
Viresh Kumarb3940582013-02-01 05:42:58 +00002071 governor->initialized = 0;
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -07002072 err = -EBUSY;
2073 if (__find_governor(governor->name) == NULL) {
2074 err = 0;
2075 list_add(&governor->governor_list, &cpufreq_governor_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002076 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002077
Dave Jones32ee8c32006-02-28 00:43:23 -05002078 mutex_unlock(&cpufreq_governor_mutex);
Jeremy Fitzhardinge3bcb09a2006-07-06 12:30:26 -07002079 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002080}
2081EXPORT_SYMBOL_GPL(cpufreq_register_governor);
2082
Linus Torvalds1da177e2005-04-16 15:20:36 -07002083void cpufreq_unregister_governor(struct cpufreq_governor *governor)
2084{
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05002085 int cpu;
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05002086
Linus Torvalds1da177e2005-04-16 15:20:36 -07002087 if (!governor)
2088 return;
2089
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002090 if (cpufreq_disabled())
2091 return;
2092
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05002093 for_each_present_cpu(cpu) {
2094 if (cpu_online(cpu))
2095 continue;
2096 if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name))
2097 strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0");
2098 }
Prarit Bhargava90e41ba2009-11-12 09:18:46 -05002099
akpm@osdl.org3fc54d32006-01-13 15:54:22 -08002100 mutex_lock(&cpufreq_governor_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002101 list_del(&governor->governor_list);
akpm@osdl.org3fc54d32006-01-13 15:54:22 -08002102 mutex_unlock(&cpufreq_governor_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002103 return;
2104}
2105EXPORT_SYMBOL_GPL(cpufreq_unregister_governor);
2106
2107
Linus Torvalds1da177e2005-04-16 15:20:36 -07002108/*********************************************************************
2109 * POLICY INTERFACE *
2110 *********************************************************************/
2111
2112/**
2113 * cpufreq_get_policy - get the current cpufreq_policy
Dave Jones29464f22009-01-18 01:37:11 -05002114 * @policy: struct cpufreq_policy into which the current cpufreq_policy
2115 * is written
Linus Torvalds1da177e2005-04-16 15:20:36 -07002116 *
2117 * Reads the current cpufreq policy.
2118 */
2119int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
2120{
2121 struct cpufreq_policy *cpu_policy;
2122 if (!policy)
2123 return -EINVAL;
2124
2125 cpu_policy = cpufreq_cpu_get(cpu);
2126 if (!cpu_policy)
2127 return -EINVAL;
2128
Viresh Kumard5b73cd2013-08-06 22:53:06 +05302129 memcpy(policy, cpu_policy, sizeof(*policy));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002130
2131 cpufreq_cpu_put(cpu_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002132 return 0;
2133}
2134EXPORT_SYMBOL(cpufreq_get_policy);
2135
Arjan van de Ven153d7f32006-07-26 15:40:07 +02002136/*
Viresh Kumar037ce832013-10-02 14:13:16 +05302137 * policy : current policy.
2138 * new_policy: policy to be set.
Arjan van de Ven153d7f32006-07-26 15:40:07 +02002139 */
Viresh Kumar037ce832013-10-02 14:13:16 +05302140static int cpufreq_set_policy(struct cpufreq_policy *policy,
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302141 struct cpufreq_policy *new_policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002142{
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002143 struct cpufreq_governor *old_gov;
2144 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002145
Joe Perchese837f9b2014-03-11 10:03:00 -07002146 pr_debug("setting new policy for CPU %u: %u - %u kHz\n",
2147 new_policy->cpu, new_policy->min, new_policy->max);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002148
Viresh Kumard5b73cd2013-08-06 22:53:06 +05302149 memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002150
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002151 if (new_policy->min > policy->max || new_policy->max < policy->min)
2152 return -EINVAL;
Mattia Dongili9c9a43e2006-07-05 23:12:20 +02002153
Linus Torvalds1da177e2005-04-16 15:20:36 -07002154 /* verify the cpu speed can be set within this limit */
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302155 ret = cpufreq_driver->verify(new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002156 if (ret)
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002157 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002158
Linus Torvalds1da177e2005-04-16 15:20:36 -07002159 /* adjust if necessary - all reasons */
Alan Sterne041c682006-03-27 01:16:30 -08002160 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302161 CPUFREQ_ADJUST, new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002162
2163 /* adjust if necessary - hardware incompatibility*/
Alan Sterne041c682006-03-27 01:16:30 -08002164 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302165 CPUFREQ_INCOMPATIBLE, new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002166
Viresh Kumarbb176f72013-06-19 14:19:33 +05302167 /*
2168 * verify the cpu speed can be set within this limit, which might be
2169 * different to the first one
2170 */
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302171 ret = cpufreq_driver->verify(new_policy);
Alan Sterne041c682006-03-27 01:16:30 -08002172 if (ret)
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002173 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002174
2175 /* notification of the new policy */
Alan Sterne041c682006-03-27 01:16:30 -08002176 blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302177 CPUFREQ_NOTIFY, new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002178
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302179 policy->min = new_policy->min;
2180 policy->max = new_policy->max;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002181
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002182 pr_debug("new min and max freqs are %u - %u kHz\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07002183 policy->min, policy->max);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002184
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002185 if (cpufreq_driver->setpolicy) {
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302186 policy->policy = new_policy->policy;
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002187 pr_debug("setting range\n");
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002188 return cpufreq_driver->setpolicy(new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002189 }
2190
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002191 if (new_policy->governor == policy->governor)
2192 goto out;
2193
2194 pr_debug("governor switch\n");
2195
2196 /* save old, working values */
2197 old_gov = policy->governor;
2198 /* end old governor */
2199 if (old_gov) {
2200 __cpufreq_governor(policy, CPUFREQ_GOV_STOP);
2201 up_write(&policy->rwsem);
Stratos Karafotise5c87b72014-03-19 23:29:17 +02002202 __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
Rafael J. Wysockid9a789c2014-02-17 22:56:35 +01002203 down_write(&policy->rwsem);
2204 }
2205
2206 /* start new governor */
2207 policy->governor = new_policy->governor;
2208 if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) {
2209 if (!__cpufreq_governor(policy, CPUFREQ_GOV_START))
2210 goto out;
2211
2212 up_write(&policy->rwsem);
2213 __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);
2214 down_write(&policy->rwsem);
2215 }
2216
2217 /* new governor failed, so re-start old one */
2218 pr_debug("starting governor %s failed\n", policy->governor->name);
2219 if (old_gov) {
2220 policy->governor = old_gov;
2221 __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT);
2222 __cpufreq_governor(policy, CPUFREQ_GOV_START);
2223 }
2224
2225 return -EINVAL;
2226
2227 out:
2228 pr_debug("governor: change or update limits\n");
2229 return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002230}
2231
2232/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07002233 * cpufreq_update_policy - re-evaluate an existing cpufreq policy
2234 * @cpu: CPU which shall be re-evaluated
2235 *
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002236 * Useful for policy notifiers which have different necessities
Linus Torvalds1da177e2005-04-16 15:20:36 -07002237 * at different times.
2238 */
2239int cpufreq_update_policy(unsigned int cpu)
2240{
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302241 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
2242 struct cpufreq_policy new_policy;
Julia Lawallf1829e42008-07-25 22:44:53 +02002243 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002244
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302245 if (!policy) {
Julia Lawallf1829e42008-07-25 22:44:53 +02002246 ret = -ENODEV;
2247 goto no_policy;
2248 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002249
viresh kumarad7722d2013-10-18 19:10:15 +05302250 down_write(&policy->rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002251
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002252 pr_debug("updating policy for CPU %u\n", cpu);
Viresh Kumard5b73cd2013-08-06 22:53:06 +05302253 memcpy(&new_policy, policy, sizeof(*policy));
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302254 new_policy.min = policy->user_policy.min;
2255 new_policy.max = policy->user_policy.max;
2256 new_policy.policy = policy->user_policy.policy;
2257 new_policy.governor = policy->user_policy.governor;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002258
Viresh Kumarbb176f72013-06-19 14:19:33 +05302259 /*
2260 * BIOS might change freq behind our back
2261 * -> ask driver for current freq and notify governors about a change
2262 */
Rafael J. Wysocki2ed99e32014-03-12 21:49:33 +01002263 if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302264 new_policy.cur = cpufreq_driver->get(cpu);
Viresh Kumarbd0fa9b2014-02-25 14:29:44 +05302265 if (WARN_ON(!new_policy.cur)) {
2266 ret = -EIO;
2267 goto no_policy;
2268 }
2269
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302270 if (!policy->cur) {
Joe Perchese837f9b2014-03-11 10:03:00 -07002271 pr_debug("Driver did not initialize current freq\n");
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302272 policy->cur = new_policy.cur;
Thomas Renningera85f7bd2006-02-01 11:36:04 +01002273 } else {
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05302274 if (policy->cur != new_policy.cur && has_target())
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302275 cpufreq_out_of_sync(cpu, policy->cur,
2276 new_policy.cur);
Thomas Renningera85f7bd2006-02-01 11:36:04 +01002277 }
Thomas Renninger0961dd02006-01-26 18:46:33 +01002278 }
2279
Viresh Kumar037ce832013-10-02 14:13:16 +05302280 ret = cpufreq_set_policy(policy, &new_policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002281
viresh kumarad7722d2013-10-18 19:10:15 +05302282 up_write(&policy->rwsem);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002283
Viresh Kumar3a3e9e02013-08-06 22:53:05 +05302284 cpufreq_cpu_put(policy);
Julia Lawallf1829e42008-07-25 22:44:53 +02002285no_policy:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002286 return ret;
2287}
2288EXPORT_SYMBOL(cpufreq_update_policy);
2289
Paul Gortmaker27609842013-06-19 13:54:04 -04002290static int cpufreq_cpu_callback(struct notifier_block *nfb,
Ashok Rajc32b6b82005-10-30 14:59:54 -08002291 unsigned long action, void *hcpu)
2292{
2293 unsigned int cpu = (unsigned long)hcpu;
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002294 struct device *dev;
Ashok Rajc32b6b82005-10-30 14:59:54 -08002295
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002296 dev = get_cpu_device(cpu);
2297 if (dev) {
Srivatsa S. Bhat5302c3f2013-07-30 04:25:25 +05302298 switch (action & ~CPU_TASKS_FROZEN) {
Ashok Rajc32b6b82005-10-30 14:59:54 -08002299 case CPU_ONLINE:
Viresh Kumar96bbbe42014-03-10 14:53:35 +05302300 __cpufreq_add_dev(dev, NULL);
Ashok Rajc32b6b82005-10-30 14:59:54 -08002301 break;
Srivatsa S. Bhat5302c3f2013-07-30 04:25:25 +05302302
Ashok Rajc32b6b82005-10-30 14:59:54 -08002303 case CPU_DOWN_PREPARE:
Viresh Kumar96bbbe42014-03-10 14:53:35 +05302304 __cpufreq_remove_dev_prepare(dev, NULL);
Srivatsa S. Bhat1aee40a2013-09-07 01:23:27 +05302305 break;
2306
2307 case CPU_POST_DEAD:
Viresh Kumar96bbbe42014-03-10 14:53:35 +05302308 __cpufreq_remove_dev_finish(dev, NULL);
Ashok Rajc32b6b82005-10-30 14:59:54 -08002309 break;
Srivatsa S. Bhat5302c3f2013-07-30 04:25:25 +05302310
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002311 case CPU_DOWN_FAILED:
Viresh Kumar96bbbe42014-03-10 14:53:35 +05302312 __cpufreq_add_dev(dev, NULL);
Ashok Rajc32b6b82005-10-30 14:59:54 -08002313 break;
2314 }
2315 }
2316 return NOTIFY_OK;
2317}
2318
Neal Buckendahl9c36f742010-06-22 22:02:44 -05002319static struct notifier_block __refdata cpufreq_cpu_notifier = {
Viresh Kumarbb176f72013-06-19 14:19:33 +05302320 .notifier_call = cpufreq_cpu_callback,
Ashok Rajc32b6b82005-10-30 14:59:54 -08002321};
Linus Torvalds1da177e2005-04-16 15:20:36 -07002322
2323/*********************************************************************
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002324 * BOOST *
2325 *********************************************************************/
2326static int cpufreq_boost_set_sw(int state)
2327{
2328 struct cpufreq_frequency_table *freq_table;
2329 struct cpufreq_policy *policy;
2330 int ret = -EINVAL;
2331
2332 list_for_each_entry(policy, &cpufreq_policy_list, policy_list) {
2333 freq_table = cpufreq_frequency_get_table(policy->cpu);
2334 if (freq_table) {
2335 ret = cpufreq_frequency_table_cpuinfo(policy,
2336 freq_table);
2337 if (ret) {
2338 pr_err("%s: Policy frequency update failed\n",
2339 __func__);
2340 break;
2341 }
2342 policy->user_policy.max = policy->max;
2343 __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);
2344 }
2345 }
2346
2347 return ret;
2348}
2349
2350int cpufreq_boost_trigger_state(int state)
2351{
2352 unsigned long flags;
2353 int ret = 0;
2354
2355 if (cpufreq_driver->boost_enabled == state)
2356 return 0;
2357
2358 write_lock_irqsave(&cpufreq_driver_lock, flags);
2359 cpufreq_driver->boost_enabled = state;
2360 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
2361
2362 ret = cpufreq_driver->set_boost(state);
2363 if (ret) {
2364 write_lock_irqsave(&cpufreq_driver_lock, flags);
2365 cpufreq_driver->boost_enabled = !state;
2366 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
2367
Joe Perchese837f9b2014-03-11 10:03:00 -07002368 pr_err("%s: Cannot %s BOOST\n",
2369 __func__, state ? "enable" : "disable");
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002370 }
2371
2372 return ret;
2373}
2374
2375int cpufreq_boost_supported(void)
2376{
2377 if (likely(cpufreq_driver))
2378 return cpufreq_driver->boost_supported;
2379
2380 return 0;
2381}
2382EXPORT_SYMBOL_GPL(cpufreq_boost_supported);
2383
2384int cpufreq_boost_enabled(void)
2385{
2386 return cpufreq_driver->boost_enabled;
2387}
2388EXPORT_SYMBOL_GPL(cpufreq_boost_enabled);
2389
2390/*********************************************************************
Linus Torvalds1da177e2005-04-16 15:20:36 -07002391 * REGISTER / UNREGISTER CPUFREQ DRIVER *
2392 *********************************************************************/
2393
2394/**
2395 * cpufreq_register_driver - register a CPU Frequency driver
2396 * @driver_data: A struct cpufreq_driver containing the values#
2397 * submitted by the CPU Frequency driver.
2398 *
Viresh Kumarbb176f72013-06-19 14:19:33 +05302399 * Registers a CPU Frequency driver to this core code. This code
Linus Torvalds1da177e2005-04-16 15:20:36 -07002400 * returns zero on success, -EBUSY when another driver got here first
Dave Jones32ee8c32006-02-28 00:43:23 -05002401 * (and isn't unregistered in the meantime).
Linus Torvalds1da177e2005-04-16 15:20:36 -07002402 *
2403 */
Linus Torvalds221dee22007-02-26 14:55:48 -08002404int cpufreq_register_driver(struct cpufreq_driver *driver_data)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002405{
2406 unsigned long flags;
2407 int ret;
2408
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002409 if (cpufreq_disabled())
2410 return -ENODEV;
2411
Linus Torvalds1da177e2005-04-16 15:20:36 -07002412 if (!driver_data || !driver_data->verify || !driver_data->init ||
Viresh Kumar9c0ebcf2013-10-25 19:45:48 +05302413 !(driver_data->setpolicy || driver_data->target_index ||
Rafael J. Wysocki98322352014-03-19 12:48:30 +01002414 driver_data->target) ||
2415 (driver_data->setpolicy && (driver_data->target_index ||
Viresh Kumar1c03a2d2014-06-02 22:49:28 +05302416 driver_data->target)) ||
2417 (!!driver_data->get_intermediate != !!driver_data->target_intermediate))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002418 return -EINVAL;
2419
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002420 pr_debug("trying to register driver %s\n", driver_data->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002421
2422 if (driver_data->setpolicy)
2423 driver_data->flags |= CPUFREQ_CONST_LOOPS;
2424
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002425 write_lock_irqsave(&cpufreq_driver_lock, flags);
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002426 if (cpufreq_driver) {
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002427 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Yinghai Lu4dea58062013-09-18 21:05:20 -07002428 return -EEXIST;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002429 }
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002430 cpufreq_driver = driver_data;
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002431 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002432
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002433 if (cpufreq_boost_supported()) {
2434 /*
2435 * Check if driver provides function to enable boost -
2436 * if not, use cpufreq_boost_set_sw as default
2437 */
2438 if (!cpufreq_driver->set_boost)
2439 cpufreq_driver->set_boost = cpufreq_boost_set_sw;
2440
2441 ret = cpufreq_sysfs_create_file(&boost.attr);
2442 if (ret) {
2443 pr_err("%s: cannot register global BOOST sysfs file\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07002444 __func__);
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002445 goto err_null_driver;
2446 }
2447 }
2448
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002449 ret = subsys_interface_register(&cpufreq_interface);
Jiri Slaby8f5bc2a2011-03-01 17:41:10 +01002450 if (ret)
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002451 goto err_boost_unreg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002452
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002453 if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002454 int i;
2455 ret = -ENODEV;
2456
2457 /* check for at least one working CPU */
Mike Travis7a6aedf2008-03-25 15:06:53 -07002458 for (i = 0; i < nr_cpu_ids; i++)
2459 if (cpu_possible(i) && per_cpu(cpufreq_cpu_data, i)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002460 ret = 0;
Mike Travis7a6aedf2008-03-25 15:06:53 -07002461 break;
2462 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002463
2464 /* if all ->init() calls failed, unregister */
2465 if (ret) {
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002466 pr_debug("no CPU initialized for driver %s\n",
Joe Perchese837f9b2014-03-11 10:03:00 -07002467 driver_data->name);
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002468 goto err_if_unreg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002469 }
2470 }
2471
Jiri Slaby8f5bc2a2011-03-01 17:41:10 +01002472 register_hotcpu_notifier(&cpufreq_cpu_notifier);
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002473 pr_debug("driver %s up and running\n", driver_data->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002474
Jiri Slaby8f5bc2a2011-03-01 17:41:10 +01002475 return 0;
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002476err_if_unreg:
2477 subsys_interface_unregister(&cpufreq_interface);
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002478err_boost_unreg:
2479 if (cpufreq_boost_supported())
2480 cpufreq_sysfs_remove_file(&boost.attr);
Jiri Slaby8f5bc2a2011-03-01 17:41:10 +01002481err_null_driver:
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002482 write_lock_irqsave(&cpufreq_driver_lock, flags);
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002483 cpufreq_driver = NULL;
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002484 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Dave Jones4d34a672008-02-07 16:33:49 -05002485 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002486}
2487EXPORT_SYMBOL_GPL(cpufreq_register_driver);
2488
Linus Torvalds1da177e2005-04-16 15:20:36 -07002489/**
2490 * cpufreq_unregister_driver - unregister the current CPUFreq driver
2491 *
Viresh Kumarbb176f72013-06-19 14:19:33 +05302492 * Unregister the current CPUFreq driver. Only call this if you have
Linus Torvalds1da177e2005-04-16 15:20:36 -07002493 * the right to do so, i.e. if you have succeeded in initialising before!
2494 * Returns zero if successful, and -EINVAL if the cpufreq_driver is
2495 * currently not initialised.
2496 */
Linus Torvalds221dee22007-02-26 14:55:48 -08002497int cpufreq_unregister_driver(struct cpufreq_driver *driver)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002498{
2499 unsigned long flags;
2500
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002501 if (!cpufreq_driver || (driver != cpufreq_driver))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002502 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002503
Dominik Brodowski2d06d8c2011-03-27 15:04:46 +02002504 pr_debug("unregistering driver %s\n", driver->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002505
Kay Sievers8a25a2f2011-12-21 14:29:42 -08002506 subsys_interface_unregister(&cpufreq_interface);
Lukasz Majewski6f19efc2013-12-20 15:24:49 +01002507 if (cpufreq_boost_supported())
2508 cpufreq_sysfs_remove_file(&boost.attr);
2509
Chandra Seetharaman65edc682006-06-27 02:54:08 -07002510 unregister_hotcpu_notifier(&cpufreq_cpu_notifier);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002511
Viresh Kumar6eed9402013-08-06 22:53:11 +05302512 down_write(&cpufreq_rwsem);
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002513 write_lock_irqsave(&cpufreq_driver_lock, flags);
Viresh Kumar6eed9402013-08-06 22:53:11 +05302514
Rafael J. Wysocki1c3d85d2013-04-29 00:08:16 +02002515 cpufreq_driver = NULL;
Viresh Kumar6eed9402013-08-06 22:53:11 +05302516
Nathan Zimmer0d1857a2013-02-22 16:24:34 +00002517 write_unlock_irqrestore(&cpufreq_driver_lock, flags);
Viresh Kumar6eed9402013-08-06 22:53:11 +05302518 up_write(&cpufreq_rwsem);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002519
2520 return 0;
2521}
2522EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002523
2524static int __init cpufreq_core_init(void)
2525{
Konrad Rzeszutek Wilka7b422c2012-03-13 19:18:39 -04002526 if (cpufreq_disabled())
2527 return -ENODEV;
2528
Viresh Kumar2361be22013-05-17 16:09:09 +05302529 cpufreq_global_kobject = kobject_create();
Thomas Renninger8aa84ad2009-07-24 15:25:05 +02002530 BUG_ON(!cpufreq_global_kobject);
2531
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002532 return 0;
2533}
Venkatesh Pallipadi5a01f2e2007-02-05 16:12:44 -08002534core_initcall(cpufreq_core_init);