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1/*
2 * linux/include/linux/cpufreq.h
3 *
4 * Copyright (C) 2001 Russell King
5 * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#ifndef _LINUX_CPUFREQ_H
12#define _LINUX_CPUFREQ_H
13
14#include <linux/clk.h>
15#include <linux/cpumask.h>
16#include <linux/completion.h>
17#include <linux/kobject.h>
18#include <linux/notifier.h>
19#include <linux/sysfs.h>
20
21/*********************************************************************
22 * CPUFREQ INTERFACE *
23 *********************************************************************/
24/*
25 * Frequency values here are CPU kHz
26 *
27 * Maximum transition latency is in nanoseconds - if it's unknown,
28 * CPUFREQ_ETERNAL shall be used.
29 */
30
31#define CPUFREQ_ETERNAL (-1)
32#define CPUFREQ_NAME_LEN 16
33/* Print length for names. Extra 1 space for accomodating '\n' in prints */
34#define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1)
35
36struct cpufreq_governor;
37
38struct cpufreq_freqs {
39 unsigned int cpu; /* cpu nr */
40 unsigned int old;
41 unsigned int new;
42 u8 flags; /* flags of cpufreq_driver, see below. */
43};
44
45struct cpufreq_cpuinfo {
46 unsigned int max_freq;
47 unsigned int min_freq;
48
49 /* in 10^(-9) s = nanoseconds */
50 unsigned int transition_latency;
51};
52
53struct cpufreq_real_policy {
54 unsigned int min; /* in kHz */
55 unsigned int max; /* in kHz */
56 unsigned int policy; /* see above */
57 struct cpufreq_governor *governor; /* see below */
58};
59
60struct cpufreq_policy {
61 /* CPUs sharing clock, require sw coordination */
62 cpumask_var_t cpus; /* Online CPUs only */
63 cpumask_var_t related_cpus; /* Online + Offline CPUs */
64
65 unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs
66 should set cpufreq */
67 unsigned int cpu; /* cpu nr of CPU managing this policy */
68 unsigned int last_cpu; /* cpu nr of previous CPU that managed
69 * this policy */
70 struct clk *clk;
71 struct cpufreq_cpuinfo cpuinfo;/* see above */
72
73 unsigned int min; /* in kHz */
74 unsigned int max; /* in kHz */
75 unsigned int cur; /* in kHz, only needed if cpufreq
76 * governors are used */
77 unsigned int policy; /* see above */
78 struct cpufreq_governor *governor; /* see below */
79 void *governor_data;
80 bool governor_enabled; /* governor start/stop flag */
81
82 struct work_struct update; /* if update_policy() needs to be
83 * called, but you're in IRQ context */
84
85 struct cpufreq_real_policy user_policy;
86
87 struct list_head policy_list;
88 struct kobject kobj;
89 struct completion kobj_unregister;
90
91 /*
92 * The rules for this semaphore:
93 * - Any routine that wants to read from the policy structure will
94 * do a down_read on this semaphore.
95 * - Any routine that will write to the policy structure and/or may take away
96 * the policy altogether (eg. CPU hotplug), will hold this lock in write
97 * mode before doing so.
98 *
99 * Additional rules:
100 * - Lock should not be held across
101 * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT);
102 */
103 struct rw_semaphore rwsem;
104};
105
106/* Only for ACPI */
107#define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
108#define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */
109#define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */
110#define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/
111
112#ifdef CONFIG_CPU_FREQ
113struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu);
114void cpufreq_cpu_put(struct cpufreq_policy *policy);
115#else
116static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
117{
118 return NULL;
119}
120static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { }
121#endif
122
123static inline bool policy_is_shared(struct cpufreq_policy *policy)
124{
125 return cpumask_weight(policy->cpus) > 1;
126}
127
128/* /sys/devices/system/cpu/cpufreq: entry point for global variables */
129extern struct kobject *cpufreq_global_kobject;
130int cpufreq_get_global_kobject(void);
131void cpufreq_put_global_kobject(void);
132int cpufreq_sysfs_create_file(const struct attribute *attr);
133void cpufreq_sysfs_remove_file(const struct attribute *attr);
134
135#ifdef CONFIG_CPU_FREQ
136unsigned int cpufreq_get(unsigned int cpu);
137unsigned int cpufreq_quick_get(unsigned int cpu);
138unsigned int cpufreq_quick_get_max(unsigned int cpu);
139void disable_cpufreq(void);
140
141u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy);
142int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
143int cpufreq_update_policy(unsigned int cpu);
144bool have_governor_per_policy(void);
145struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
146#else
147static inline unsigned int cpufreq_get(unsigned int cpu)
148{
149 return 0;
150}
151static inline unsigned int cpufreq_quick_get(unsigned int cpu)
152{
153 return 0;
154}
155static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
156{
157 return 0;
158}
159static inline void disable_cpufreq(void) { }
160#endif
161
162/*********************************************************************
163 * CPUFREQ DRIVER INTERFACE *
164 *********************************************************************/
165
166#define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */
167#define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */
168
169struct freq_attr {
170 struct attribute attr;
171 ssize_t (*show)(struct cpufreq_policy *, char *);
172 ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count);
173};
174
175#define cpufreq_freq_attr_ro(_name) \
176static struct freq_attr _name = \
177__ATTR(_name, 0444, show_##_name, NULL)
178
179#define cpufreq_freq_attr_ro_perm(_name, _perm) \
180static struct freq_attr _name = \
181__ATTR(_name, _perm, show_##_name, NULL)
182
183#define cpufreq_freq_attr_rw(_name) \
184static struct freq_attr _name = \
185__ATTR(_name, 0644, show_##_name, store_##_name)
186
187struct global_attr {
188 struct attribute attr;
189 ssize_t (*show)(struct kobject *kobj,
190 struct attribute *attr, char *buf);
191 ssize_t (*store)(struct kobject *a, struct attribute *b,
192 const char *c, size_t count);
193};
194
195#define define_one_global_ro(_name) \
196static struct global_attr _name = \
197__ATTR(_name, 0444, show_##_name, NULL)
198
199#define define_one_global_rw(_name) \
200static struct global_attr _name = \
201__ATTR(_name, 0644, show_##_name, store_##_name)
202
203
204struct cpufreq_driver {
205 char name[CPUFREQ_NAME_LEN];
206 u8 flags;
207
208 /* needed by all drivers */
209 int (*init) (struct cpufreq_policy *policy);
210 int (*verify) (struct cpufreq_policy *policy);
211
212 /* define one out of two */
213 int (*setpolicy) (struct cpufreq_policy *policy);
214 int (*target) (struct cpufreq_policy *policy, /* Deprecated */
215 unsigned int target_freq,
216 unsigned int relation);
217 int (*target_index) (struct cpufreq_policy *policy,
218 unsigned int index);
219
220 /* should be defined, if possible */
221 unsigned int (*get) (unsigned int cpu);
222
223 /* optional */
224 int (*bios_limit) (int cpu, unsigned int *limit);
225
226 int (*exit) (struct cpufreq_policy *policy);
227 int (*suspend) (struct cpufreq_policy *policy);
228 int (*resume) (struct cpufreq_policy *policy);
229 struct freq_attr **attr;
230
231 /* platform specific boost support code */
232 bool boost_supported;
233 bool boost_enabled;
234 int (*set_boost) (int state);
235};
236
237/* flags */
238#define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if
239 all ->init() calls failed */
240#define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other
241 kernel "constants" aren't
242 affected by frequency
243 transitions */
244#define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume
245 speed mismatches */
246
247/*
248 * This should be set by platforms having multiple clock-domains, i.e.
249 * supporting multiple policies. With this sysfs directories of governor would
250 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same
251 * governor with different tunables for different clusters.
252 */
253#define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3)
254
255/*
256 * Driver will do POSTCHANGE notifications from outside of their ->target()
257 * routine and so must set cpufreq_driver->flags with this flag, so that core
258 * can handle them specially.
259 */
260#define CPUFREQ_ASYNC_NOTIFICATION (1 << 4)
261
262/*
263 * Set by drivers which want cpufreq core to check if CPU is running at a
264 * frequency present in freq-table exposed by the driver. For these drivers if
265 * CPU is found running at an out of table freq, we will try to set it to a freq
266 * from the table. And if that fails, we will stop further boot process by
267 * issuing a BUG_ON().
268 */
269#define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5)
270
271int cpufreq_register_driver(struct cpufreq_driver *driver_data);
272int cpufreq_unregister_driver(struct cpufreq_driver *driver_data);
273
274const char *cpufreq_get_current_driver(void);
275
276static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy,
277 unsigned int min, unsigned int max)
278{
279 if (policy->min < min)
280 policy->min = min;
281 if (policy->max < min)
282 policy->max = min;
283 if (policy->min > max)
284 policy->min = max;
285 if (policy->max > max)
286 policy->max = max;
287 if (policy->min > policy->max)
288 policy->min = policy->max;
289 return;
290}
291
292static inline void
293cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy)
294{
295 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
296 policy->cpuinfo.max_freq);
297}
298
299/*********************************************************************
300 * CPUFREQ NOTIFIER INTERFACE *
301 *********************************************************************/
302
303#define CPUFREQ_TRANSITION_NOTIFIER (0)
304#define CPUFREQ_POLICY_NOTIFIER (1)
305
306/* Transition notifiers */
307#define CPUFREQ_PRECHANGE (0)
308#define CPUFREQ_POSTCHANGE (1)
309#define CPUFREQ_RESUMECHANGE (8)
310#define CPUFREQ_SUSPENDCHANGE (9)
311
312/* Policy Notifiers */
313#define CPUFREQ_ADJUST (0)
314#define CPUFREQ_INCOMPATIBLE (1)
315#define CPUFREQ_NOTIFY (2)
316#define CPUFREQ_START (3)
317#define CPUFREQ_UPDATE_POLICY_CPU (4)
318#define CPUFREQ_CREATE_POLICY (5)
319#define CPUFREQ_REMOVE_POLICY (6)
320
321#ifdef CONFIG_CPU_FREQ
322int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);
323int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);
324
325void cpufreq_notify_transition(struct cpufreq_policy *policy,
326 struct cpufreq_freqs *freqs, unsigned int state);
327void cpufreq_notify_post_transition(struct cpufreq_policy *policy,
328 struct cpufreq_freqs *freqs, int transition_failed);
329
330#else /* CONFIG_CPU_FREQ */
331static inline int cpufreq_register_notifier(struct notifier_block *nb,
332 unsigned int list)
333{
334 return 0;
335}
336static inline int cpufreq_unregister_notifier(struct notifier_block *nb,
337 unsigned int list)
338{
339 return 0;
340}
341#endif /* !CONFIG_CPU_FREQ */
342
343/**
344 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch
345 * safe)
346 * @old: old value
347 * @div: divisor
348 * @mult: multiplier
349 *
350 *
351 * new = old * mult / div
352 */
353static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
354 u_int mult)
355{
356#if BITS_PER_LONG == 32
357 u64 result = ((u64) old) * ((u64) mult);
358 do_div(result, div);
359 return (unsigned long) result;
360
361#elif BITS_PER_LONG == 64
362 unsigned long result = old * ((u64) mult);
363 result /= div;
364 return result;
365#endif
366}
367
368/*********************************************************************
369 * CPUFREQ GOVERNORS *
370 *********************************************************************/
371
372/*
373 * If (cpufreq_driver->target) exists, the ->governor decides what frequency
374 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these
375 * two generic policies are available:
376 */
377#define CPUFREQ_POLICY_POWERSAVE (1)
378#define CPUFREQ_POLICY_PERFORMANCE (2)
379
380/* Governor Events */
381#define CPUFREQ_GOV_START 1
382#define CPUFREQ_GOV_STOP 2
383#define CPUFREQ_GOV_LIMITS 3
384#define CPUFREQ_GOV_POLICY_INIT 4
385#define CPUFREQ_GOV_POLICY_EXIT 5
386
387struct cpufreq_governor {
388 char name[CPUFREQ_NAME_LEN];
389 int initialized;
390 int (*governor) (struct cpufreq_policy *policy,
391 unsigned int event);
392 ssize_t (*show_setspeed) (struct cpufreq_policy *policy,
393 char *buf);
394 int (*store_setspeed) (struct cpufreq_policy *policy,
395 unsigned int freq);
396 unsigned int max_transition_latency; /* HW must be able to switch to
397 next freq faster than this value in nano secs or we
398 will fallback to performance governor */
399 struct list_head governor_list;
400 struct module *owner;
401};
402
403/* Pass a target to the cpufreq driver */
404int cpufreq_driver_target(struct cpufreq_policy *policy,
405 unsigned int target_freq,
406 unsigned int relation);
407int __cpufreq_driver_target(struct cpufreq_policy *policy,
408 unsigned int target_freq,
409 unsigned int relation);
410int cpufreq_register_governor(struct cpufreq_governor *governor);
411void cpufreq_unregister_governor(struct cpufreq_governor *governor);
412
413/* CPUFREQ DEFAULT GOVERNOR */
414/*
415 * Performance governor is fallback governor if any other gov failed to auto
416 * load due latency restrictions
417 */
418#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
419extern struct cpufreq_governor cpufreq_gov_performance;
420#endif
421#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
422#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance)
423#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE)
424extern struct cpufreq_governor cpufreq_gov_powersave;
425#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave)
426#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
427extern struct cpufreq_governor cpufreq_gov_userspace;
428#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace)
429#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
430extern struct cpufreq_governor cpufreq_gov_ondemand;
431#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand)
432#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
433extern struct cpufreq_governor cpufreq_gov_conservative;
434#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative)
435#endif
436
437/*********************************************************************
438 * FREQUENCY TABLE HELPERS *
439 *********************************************************************/
440
441#define CPUFREQ_ENTRY_INVALID ~0
442#define CPUFREQ_TABLE_END ~1
443#define CPUFREQ_BOOST_FREQ ~2
444
445struct cpufreq_frequency_table {
446 unsigned int driver_data; /* driver specific data, not used by core */
447 unsigned int frequency; /* kHz - doesn't need to be in ascending
448 * order */
449};
450
451int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
452 struct cpufreq_frequency_table *table);
453
454int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
455 struct cpufreq_frequency_table *table);
456int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy);
457
458int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
459 struct cpufreq_frequency_table *table,
460 unsigned int target_freq,
461 unsigned int relation,
462 unsigned int *index);
463int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
464 unsigned int freq);
465
466void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy);
467ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf);
468
469#ifdef CONFIG_CPU_FREQ
470int cpufreq_boost_trigger_state(int state);
471int cpufreq_boost_supported(void);
472int cpufreq_boost_enabled(void);
473#else
474static inline int cpufreq_boost_trigger_state(int state)
475{
476 return 0;
477}
478static inline int cpufreq_boost_supported(void)
479{
480 return 0;
481}
482static inline int cpufreq_boost_enabled(void)
483{
484 return 0;
485}
486#endif
487/* the following funtion is for cpufreq core use only */
488struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu);
489
490/* the following are really really optional */
491extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
492extern struct freq_attr *cpufreq_generic_attr[];
493void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
494 unsigned int cpu);
495void cpufreq_frequency_table_put_attr(unsigned int cpu);
496int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
497 struct cpufreq_frequency_table *table);
498
499unsigned int cpufreq_generic_get(unsigned int cpu);
500int cpufreq_generic_init(struct cpufreq_policy *policy,
501 struct cpufreq_frequency_table *table,
502 unsigned int transition_latency);
503static inline int cpufreq_generic_exit(struct cpufreq_policy *policy)
504{
505 cpufreq_frequency_table_put_attr(policy->cpu);
506 return 0;
507}
508
509#endif /* _LINUX_CPUFREQ_H */