2 * linux/include/linux/cpufreq.h
4 * Copyright (C) 2001 Russell King
5 * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
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.
11 #ifndef _LINUX_CPUFREQ_H
12 #define _LINUX_CPUFREQ_H
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/spinlock.h>
20 #include <linux/sysfs.h>
22 /*********************************************************************
24 *********************************************************************/
26 * Frequency values here are CPU kHz
28 * Maximum transition latency is in nanoseconds - if it's unknown,
29 * CPUFREQ_ETERNAL shall be used.
32 #define CPUFREQ_ETERNAL (-1)
33 #define CPUFREQ_NAME_LEN 16
34 /* Print length for names. Extra 1 space for accomodating '\n' in prints */
35 #define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1)
37 struct cpufreq_governor
;
39 struct cpufreq_freqs
{
40 unsigned int cpu
; /* cpu nr */
43 u8 flags
; /* flags of cpufreq_driver, see below. */
46 struct cpufreq_cpuinfo
{
47 unsigned int max_freq
;
48 unsigned int min_freq
;
50 /* in 10^(-9) s = nanoseconds */
51 unsigned int transition_latency
;
54 struct cpufreq_real_policy
{
55 unsigned int min
; /* in kHz */
56 unsigned int max
; /* in kHz */
57 unsigned int policy
; /* see above */
58 struct cpufreq_governor
*governor
; /* see below */
61 struct cpufreq_policy
{
62 /* CPUs sharing clock, require sw coordination */
63 cpumask_var_t cpus
; /* Online CPUs only */
64 cpumask_var_t related_cpus
; /* Online + Offline CPUs */
66 unsigned int shared_type
; /* ACPI: ANY or ALL affected CPUs
68 unsigned int cpu
; /* cpu managing this policy, must be online */
69 unsigned int kobj_cpu
; /* cpu managing sysfs files, can be offline */
72 struct cpufreq_cpuinfo cpuinfo
;/* see above */
74 unsigned int min
; /* in kHz */
75 unsigned int max
; /* in kHz */
76 unsigned int cur
; /* in kHz, only needed if cpufreq
77 * governors are used */
78 unsigned int restore_freq
; /* = policy->cur before transition */
79 unsigned int suspend_freq
; /* freq to set during suspend */
81 unsigned int policy
; /* see above */
82 struct cpufreq_governor
*governor
; /* see below */
84 bool governor_enabled
; /* governor start/stop flag */
85 char last_governor
[CPUFREQ_NAME_LEN
]; /* last governor used */
87 struct work_struct update
; /* if update_policy() needs to be
88 * called, but you're in IRQ context */
90 struct cpufreq_real_policy user_policy
;
91 struct cpufreq_frequency_table
*freq_table
;
93 struct list_head policy_list
;
95 struct completion kobj_unregister
;
98 * The rules for this semaphore:
99 * - Any routine that wants to read from the policy structure will
100 * do a down_read on this semaphore.
101 * - Any routine that will write to the policy structure and/or may take away
102 * the policy altogether (eg. CPU hotplug), will hold this lock in write
103 * mode before doing so.
106 * - Lock should not be held across
107 * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT);
109 struct rw_semaphore rwsem
;
111 /* Synchronization for frequency transitions */
112 bool transition_ongoing
; /* Tracks transition status */
113 spinlock_t transition_lock
;
114 wait_queue_head_t transition_wait
;
115 struct task_struct
*transition_task
; /* Task which is doing the transition */
118 struct cpufreq_stats
*stats
;
120 /* For cpufreq driver's internal use */
125 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
126 #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */
127 #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */
128 #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/
130 #ifdef CONFIG_CPU_FREQ
131 struct cpufreq_policy
*cpufreq_cpu_get(unsigned int cpu
);
132 void cpufreq_cpu_put(struct cpufreq_policy
*policy
);
134 static inline struct cpufreq_policy
*cpufreq_cpu_get(unsigned int cpu
)
138 static inline void cpufreq_cpu_put(struct cpufreq_policy
*policy
) { }
141 static inline bool policy_is_shared(struct cpufreq_policy
*policy
)
143 return cpumask_weight(policy
->cpus
) > 1;
146 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */
147 extern struct kobject
*cpufreq_global_kobject
;
148 int cpufreq_get_global_kobject(void);
149 void cpufreq_put_global_kobject(void);
150 int cpufreq_sysfs_create_file(const struct attribute
*attr
);
151 void cpufreq_sysfs_remove_file(const struct attribute
*attr
);
153 #ifdef CONFIG_CPU_FREQ
154 unsigned int cpufreq_get(unsigned int cpu
);
155 unsigned int cpufreq_quick_get(unsigned int cpu
);
156 unsigned int cpufreq_quick_get_max(unsigned int cpu
);
157 void disable_cpufreq(void);
159 u64
get_cpu_idle_time(unsigned int cpu
, u64
*wall
, int io_busy
);
160 int cpufreq_get_policy(struct cpufreq_policy
*policy
, unsigned int cpu
);
161 int cpufreq_update_policy(unsigned int cpu
);
162 bool have_governor_per_policy(void);
163 struct kobject
*get_governor_parent_kobj(struct cpufreq_policy
*policy
);
165 static inline unsigned int cpufreq_get(unsigned int cpu
)
169 static inline unsigned int cpufreq_quick_get(unsigned int cpu
)
173 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu
)
177 static inline void disable_cpufreq(void) { }
180 /*********************************************************************
181 * CPUFREQ DRIVER INTERFACE *
182 *********************************************************************/
184 #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */
185 #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */
186 #define CPUFREQ_RELATION_C 2 /* closest frequency to target */
189 struct attribute attr
;
190 ssize_t (*show
)(struct cpufreq_policy
*, char *);
191 ssize_t (*store
)(struct cpufreq_policy
*, const char *, size_t count
);
194 #define cpufreq_freq_attr_ro(_name) \
195 static struct freq_attr _name = \
196 __ATTR(_name, 0444, show_##_name, NULL)
198 #define cpufreq_freq_attr_ro_perm(_name, _perm) \
199 static struct freq_attr _name = \
200 __ATTR(_name, _perm, show_##_name, NULL)
202 #define cpufreq_freq_attr_rw(_name) \
203 static struct freq_attr _name = \
204 __ATTR(_name, 0644, show_##_name, store_##_name)
207 struct attribute attr
;
208 ssize_t (*show
)(struct kobject
*kobj
,
209 struct attribute
*attr
, char *buf
);
210 ssize_t (*store
)(struct kobject
*a
, struct attribute
*b
,
211 const char *c
, size_t count
);
214 #define define_one_global_ro(_name) \
215 static struct global_attr _name = \
216 __ATTR(_name, 0444, show_##_name, NULL)
218 #define define_one_global_rw(_name) \
219 static struct global_attr _name = \
220 __ATTR(_name, 0644, show_##_name, store_##_name)
223 struct cpufreq_driver
{
224 char name
[CPUFREQ_NAME_LEN
];
228 /* needed by all drivers */
229 int (*init
)(struct cpufreq_policy
*policy
);
230 int (*verify
)(struct cpufreq_policy
*policy
);
232 /* define one out of two */
233 int (*setpolicy
)(struct cpufreq_policy
*policy
);
236 * On failure, should always restore frequency to policy->restore_freq
239 int (*target
)(struct cpufreq_policy
*policy
,
240 unsigned int target_freq
,
241 unsigned int relation
); /* Deprecated */
242 int (*target_index
)(struct cpufreq_policy
*policy
,
245 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION
248 * get_intermediate should return a stable intermediate frequency
249 * platform wants to switch to and target_intermediate() should set CPU
250 * to to that frequency, before jumping to the frequency corresponding
251 * to 'index'. Core will take care of sending notifications and driver
252 * doesn't have to handle them in target_intermediate() or
255 * Drivers can return '0' from get_intermediate() in case they don't
256 * wish to switch to intermediate frequency for some target frequency.
257 * In that case core will directly call ->target_index().
259 unsigned int (*get_intermediate
)(struct cpufreq_policy
*policy
,
261 int (*target_intermediate
)(struct cpufreq_policy
*policy
,
264 /* should be defined, if possible */
265 unsigned int (*get
)(unsigned int cpu
);
268 int (*bios_limit
)(int cpu
, unsigned int *limit
);
270 int (*exit
)(struct cpufreq_policy
*policy
);
271 void (*stop_cpu
)(struct cpufreq_policy
*policy
);
272 int (*suspend
)(struct cpufreq_policy
*policy
);
273 int (*resume
)(struct cpufreq_policy
*policy
);
275 /* Will be called after the driver is fully initialized */
276 void (*ready
)(struct cpufreq_policy
*policy
);
278 struct freq_attr
**attr
;
280 /* platform specific boost support code */
281 bool boost_supported
;
283 int (*set_boost
)(int state
);
287 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if
288 all ->init() calls failed */
289 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other
290 kernel "constants" aren't
291 affected by frequency
293 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume
297 * This should be set by platforms having multiple clock-domains, i.e.
298 * supporting multiple policies. With this sysfs directories of governor would
299 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same
300 * governor with different tunables for different clusters.
302 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3)
305 * Driver will do POSTCHANGE notifications from outside of their ->target()
306 * routine and so must set cpufreq_driver->flags with this flag, so that core
307 * can handle them specially.
309 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4)
312 * Set by drivers which want cpufreq core to check if CPU is running at a
313 * frequency present in freq-table exposed by the driver. For these drivers if
314 * CPU is found running at an out of table freq, we will try to set it to a freq
315 * from the table. And if that fails, we will stop further boot process by
316 * issuing a BUG_ON().
318 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5)
320 int cpufreq_register_driver(struct cpufreq_driver
*driver_data
);
321 int cpufreq_unregister_driver(struct cpufreq_driver
*driver_data
);
323 const char *cpufreq_get_current_driver(void);
324 void *cpufreq_get_driver_data(void);
326 static inline void cpufreq_verify_within_limits(struct cpufreq_policy
*policy
,
327 unsigned int min
, unsigned int max
)
329 if (policy
->min
< min
)
331 if (policy
->max
< min
)
333 if (policy
->min
> max
)
335 if (policy
->max
> max
)
337 if (policy
->min
> policy
->max
)
338 policy
->min
= policy
->max
;
343 cpufreq_verify_within_cpu_limits(struct cpufreq_policy
*policy
)
345 cpufreq_verify_within_limits(policy
, policy
->cpuinfo
.min_freq
,
346 policy
->cpuinfo
.max_freq
);
349 #ifdef CONFIG_CPU_FREQ
350 void cpufreq_suspend(void);
351 void cpufreq_resume(void);
352 int cpufreq_generic_suspend(struct cpufreq_policy
*policy
);
354 static inline void cpufreq_suspend(void) {}
355 static inline void cpufreq_resume(void) {}
358 /*********************************************************************
359 * CPUFREQ NOTIFIER INTERFACE *
360 *********************************************************************/
362 #define CPUFREQ_TRANSITION_NOTIFIER (0)
363 #define CPUFREQ_POLICY_NOTIFIER (1)
365 /* Transition notifiers */
366 #define CPUFREQ_PRECHANGE (0)
367 #define CPUFREQ_POSTCHANGE (1)
369 /* Policy Notifiers */
370 #define CPUFREQ_ADJUST (0)
371 #define CPUFREQ_INCOMPATIBLE (1)
372 #define CPUFREQ_NOTIFY (2)
373 #define CPUFREQ_START (3)
374 #define CPUFREQ_CREATE_POLICY (4)
375 #define CPUFREQ_REMOVE_POLICY (5)
377 #ifdef CONFIG_CPU_FREQ
378 int cpufreq_register_notifier(struct notifier_block
*nb
, unsigned int list
);
379 int cpufreq_unregister_notifier(struct notifier_block
*nb
, unsigned int list
);
381 void cpufreq_freq_transition_begin(struct cpufreq_policy
*policy
,
382 struct cpufreq_freqs
*freqs
);
383 void cpufreq_freq_transition_end(struct cpufreq_policy
*policy
,
384 struct cpufreq_freqs
*freqs
, int transition_failed
);
386 #else /* CONFIG_CPU_FREQ */
387 static inline int cpufreq_register_notifier(struct notifier_block
*nb
,
392 static inline int cpufreq_unregister_notifier(struct notifier_block
*nb
,
397 #endif /* !CONFIG_CPU_FREQ */
400 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch
407 * new = old * mult / div
409 static inline unsigned long cpufreq_scale(unsigned long old
, u_int div
,
412 #if BITS_PER_LONG == 32
413 u64 result
= ((u64
) old
) * ((u64
) mult
);
415 return (unsigned long) result
;
417 #elif BITS_PER_LONG == 64
418 unsigned long result
= old
* ((u64
) mult
);
424 /*********************************************************************
425 * CPUFREQ GOVERNORS *
426 *********************************************************************/
429 * If (cpufreq_driver->target) exists, the ->governor decides what frequency
430 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these
431 * two generic policies are available:
433 #define CPUFREQ_POLICY_POWERSAVE (1)
434 #define CPUFREQ_POLICY_PERFORMANCE (2)
436 /* Governor Events */
437 #define CPUFREQ_GOV_START 1
438 #define CPUFREQ_GOV_STOP 2
439 #define CPUFREQ_GOV_LIMITS 3
440 #define CPUFREQ_GOV_POLICY_INIT 4
441 #define CPUFREQ_GOV_POLICY_EXIT 5
443 struct cpufreq_governor
{
444 char name
[CPUFREQ_NAME_LEN
];
446 int (*governor
) (struct cpufreq_policy
*policy
,
448 ssize_t (*show_setspeed
) (struct cpufreq_policy
*policy
,
450 int (*store_setspeed
) (struct cpufreq_policy
*policy
,
452 unsigned int max_transition_latency
; /* HW must be able to switch to
453 next freq faster than this value in nano secs or we
454 will fallback to performance governor */
455 struct list_head governor_list
;
456 struct module
*owner
;
459 /* Pass a target to the cpufreq driver */
460 int cpufreq_driver_target(struct cpufreq_policy
*policy
,
461 unsigned int target_freq
,
462 unsigned int relation
);
463 int __cpufreq_driver_target(struct cpufreq_policy
*policy
,
464 unsigned int target_freq
,
465 unsigned int relation
);
466 int cpufreq_register_governor(struct cpufreq_governor
*governor
);
467 void cpufreq_unregister_governor(struct cpufreq_governor
*governor
);
469 /* CPUFREQ DEFAULT GOVERNOR */
471 * Performance governor is fallback governor if any other gov failed to auto
472 * load due latency restrictions
474 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
475 extern struct cpufreq_governor cpufreq_gov_performance
;
477 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
478 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance)
479 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE)
480 extern struct cpufreq_governor cpufreq_gov_powersave
;
481 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave)
482 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
483 extern struct cpufreq_governor cpufreq_gov_userspace
;
484 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace)
485 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
486 extern struct cpufreq_governor cpufreq_gov_ondemand
;
487 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand)
488 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
489 extern struct cpufreq_governor cpufreq_gov_conservative
;
490 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative)
493 /*********************************************************************
494 * FREQUENCY TABLE HELPERS *
495 *********************************************************************/
497 /* Special Values of .frequency field */
498 #define CPUFREQ_ENTRY_INVALID ~0u
499 #define CPUFREQ_TABLE_END ~1u
500 /* Special Values of .flags field */
501 #define CPUFREQ_BOOST_FREQ (1 << 0)
503 struct cpufreq_frequency_table
{
505 unsigned int driver_data
; /* driver specific data, not used by core */
506 unsigned int frequency
; /* kHz - doesn't need to be in ascending
510 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP)
511 int dev_pm_opp_init_cpufreq_table(struct device
*dev
,
512 struct cpufreq_frequency_table
**table
);
513 void dev_pm_opp_free_cpufreq_table(struct device
*dev
,
514 struct cpufreq_frequency_table
**table
);
516 static inline int dev_pm_opp_init_cpufreq_table(struct device
*dev
,
517 struct cpufreq_frequency_table
523 static inline void dev_pm_opp_free_cpufreq_table(struct device
*dev
,
524 struct cpufreq_frequency_table
530 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table
**pos
)
532 while ((*pos
)->frequency
!= CPUFREQ_TABLE_END
)
533 if ((*pos
)->frequency
!= CPUFREQ_ENTRY_INVALID
)
541 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table
542 * @pos: the cpufreq_frequency_table * to use as a loop cursor.
543 * @table: the cpufreq_frequency_table * to iterate over.
546 #define cpufreq_for_each_entry(pos, table) \
547 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)
550 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table
551 * excluding CPUFREQ_ENTRY_INVALID frequencies.
552 * @pos: the cpufreq_frequency_table * to use as a loop cursor.
553 * @table: the cpufreq_frequency_table * to iterate over.
556 #define cpufreq_for_each_valid_entry(pos, table) \
557 for (pos = table; cpufreq_next_valid(&pos); pos++)
559 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy
*policy
,
560 struct cpufreq_frequency_table
*table
);
562 int cpufreq_frequency_table_verify(struct cpufreq_policy
*policy
,
563 struct cpufreq_frequency_table
*table
);
564 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy
*policy
);
566 int cpufreq_frequency_table_target(struct cpufreq_policy
*policy
,
567 struct cpufreq_frequency_table
*table
,
568 unsigned int target_freq
,
569 unsigned int relation
,
570 unsigned int *index
);
571 int cpufreq_frequency_table_get_index(struct cpufreq_policy
*policy
,
574 ssize_t
cpufreq_show_cpus(const struct cpumask
*mask
, char *buf
);
576 #ifdef CONFIG_CPU_FREQ
577 int cpufreq_boost_trigger_state(int state
);
578 int cpufreq_boost_supported(void);
579 int cpufreq_boost_enabled(void);
581 static inline int cpufreq_boost_trigger_state(int state
)
585 static inline int cpufreq_boost_supported(void)
589 static inline int cpufreq_boost_enabled(void)
594 /* the following funtion is for cpufreq core use only */
595 struct cpufreq_frequency_table
*cpufreq_frequency_get_table(unsigned int cpu
);
597 /* the following are really really optional */
598 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs
;
599 extern struct freq_attr
*cpufreq_generic_attr
[];
600 int cpufreq_table_validate_and_show(struct cpufreq_policy
*policy
,
601 struct cpufreq_frequency_table
*table
);
603 unsigned int cpufreq_generic_get(unsigned int cpu
);
604 int cpufreq_generic_init(struct cpufreq_policy
*policy
,
605 struct cpufreq_frequency_table
*table
,
606 unsigned int transition_latency
);
607 #endif /* _LINUX_CPUFREQ_H */