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 nr of CPU managing this policy */
70 struct cpufreq_cpuinfo cpuinfo
;/* see above */
72 unsigned int min
; /* in kHz */
73 unsigned int max
; /* in kHz */
74 unsigned int cur
; /* in kHz, only needed if cpufreq
75 * governors are used */
76 unsigned int restore_freq
; /* = policy->cur before transition */
77 unsigned int suspend_freq
; /* freq to set during suspend */
79 unsigned int policy
; /* see above */
80 struct cpufreq_governor
*governor
; /* see below */
82 bool governor_enabled
; /* governor start/stop flag */
84 struct work_struct update
; /* if update_policy() needs to be
85 * called, but you're in IRQ context */
87 struct cpufreq_real_policy user_policy
;
88 struct cpufreq_frequency_table
*freq_table
;
90 struct list_head policy_list
;
92 struct completion kobj_unregister
;
95 * The rules for this semaphore:
96 * - Any routine that wants to read from the policy structure will
97 * do a down_read on this semaphore.
98 * - Any routine that will write to the policy structure and/or may take away
99 * the policy altogether (eg. CPU hotplug), will hold this lock in write
100 * mode before doing so.
103 * - Lock should not be held across
104 * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT);
106 struct rw_semaphore rwsem
;
108 /* Synchronization for frequency transitions */
109 bool transition_ongoing
; /* Tracks transition status */
110 spinlock_t transition_lock
;
111 wait_queue_head_t transition_wait
;
112 struct task_struct
*transition_task
; /* Task which is doing the transition */
115 struct cpufreq_stats
*stats
;
117 /* For cpufreq driver's internal use */
122 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
123 #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */
124 #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */
125 #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/
127 #ifdef CONFIG_CPU_FREQ
128 struct cpufreq_policy
*cpufreq_cpu_get(unsigned int cpu
);
129 void cpufreq_cpu_put(struct cpufreq_policy
*policy
);
131 static inline struct cpufreq_policy
*cpufreq_cpu_get(unsigned int cpu
)
135 static inline void cpufreq_cpu_put(struct cpufreq_policy
*policy
) { }
138 static inline bool policy_is_shared(struct cpufreq_policy
*policy
)
140 return cpumask_weight(policy
->cpus
) > 1;
143 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */
144 extern struct kobject
*cpufreq_global_kobject
;
145 int cpufreq_get_global_kobject(void);
146 void cpufreq_put_global_kobject(void);
147 int cpufreq_sysfs_create_file(const struct attribute
*attr
);
148 void cpufreq_sysfs_remove_file(const struct attribute
*attr
);
150 #ifdef CONFIG_CPU_FREQ
151 unsigned int cpufreq_get(unsigned int cpu
);
152 unsigned int cpufreq_quick_get(unsigned int cpu
);
153 unsigned int cpufreq_quick_get_max(unsigned int cpu
);
154 void disable_cpufreq(void);
156 u64
get_cpu_idle_time(unsigned int cpu
, u64
*wall
, int io_busy
);
157 int cpufreq_get_policy(struct cpufreq_policy
*policy
, unsigned int cpu
);
158 int cpufreq_update_policy(unsigned int cpu
);
159 bool have_governor_per_policy(void);
160 struct kobject
*get_governor_parent_kobj(struct cpufreq_policy
*policy
);
162 static inline unsigned int cpufreq_get(unsigned int cpu
)
166 static inline unsigned int cpufreq_quick_get(unsigned int cpu
)
170 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu
)
174 static inline void disable_cpufreq(void) { }
177 /*********************************************************************
178 * CPUFREQ DRIVER INTERFACE *
179 *********************************************************************/
181 #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */
182 #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */
183 #define CPUFREQ_RELATION_C 2 /* closest frequency to target */
186 struct attribute attr
;
187 ssize_t (*show
)(struct cpufreq_policy
*, char *);
188 ssize_t (*store
)(struct cpufreq_policy
*, const char *, size_t count
);
191 #define cpufreq_freq_attr_ro(_name) \
192 static struct freq_attr _name = \
193 __ATTR(_name, 0444, show_##_name, NULL)
195 #define cpufreq_freq_attr_ro_perm(_name, _perm) \
196 static struct freq_attr _name = \
197 __ATTR(_name, _perm, show_##_name, NULL)
199 #define cpufreq_freq_attr_rw(_name) \
200 static struct freq_attr _name = \
201 __ATTR(_name, 0644, show_##_name, store_##_name)
204 struct attribute attr
;
205 ssize_t (*show
)(struct kobject
*kobj
,
206 struct attribute
*attr
, char *buf
);
207 ssize_t (*store
)(struct kobject
*a
, struct attribute
*b
,
208 const char *c
, size_t count
);
211 #define define_one_global_ro(_name) \
212 static struct global_attr _name = \
213 __ATTR(_name, 0444, show_##_name, NULL)
215 #define define_one_global_rw(_name) \
216 static struct global_attr _name = \
217 __ATTR(_name, 0644, show_##_name, store_##_name)
220 struct cpufreq_driver
{
221 char name
[CPUFREQ_NAME_LEN
];
225 /* needed by all drivers */
226 int (*init
)(struct cpufreq_policy
*policy
);
227 int (*verify
)(struct cpufreq_policy
*policy
);
229 /* define one out of two */
230 int (*setpolicy
)(struct cpufreq_policy
*policy
);
233 * On failure, should always restore frequency to policy->restore_freq
236 int (*target
)(struct cpufreq_policy
*policy
,
237 unsigned int target_freq
,
238 unsigned int relation
); /* Deprecated */
239 int (*target_index
)(struct cpufreq_policy
*policy
,
242 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION
245 * get_intermediate should return a stable intermediate frequency
246 * platform wants to switch to and target_intermediate() should set CPU
247 * to to that frequency, before jumping to the frequency corresponding
248 * to 'index'. Core will take care of sending notifications and driver
249 * doesn't have to handle them in target_intermediate() or
252 * Drivers can return '0' from get_intermediate() in case they don't
253 * wish to switch to intermediate frequency for some target frequency.
254 * In that case core will directly call ->target_index().
256 unsigned int (*get_intermediate
)(struct cpufreq_policy
*policy
,
258 int (*target_intermediate
)(struct cpufreq_policy
*policy
,
261 /* should be defined, if possible */
262 unsigned int (*get
)(unsigned int cpu
);
265 int (*bios_limit
)(int cpu
, unsigned int *limit
);
267 int (*exit
)(struct cpufreq_policy
*policy
);
268 void (*stop_cpu
)(struct cpufreq_policy
*policy
);
269 int (*suspend
)(struct cpufreq_policy
*policy
);
270 int (*resume
)(struct cpufreq_policy
*policy
);
272 /* Will be called after the driver is fully initialized */
273 void (*ready
)(struct cpufreq_policy
*policy
);
275 struct freq_attr
**attr
;
277 /* platform specific boost support code */
278 bool boost_supported
;
280 int (*set_boost
)(int state
);
284 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if
285 all ->init() calls failed */
286 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other
287 kernel "constants" aren't
288 affected by frequency
290 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume
294 * This should be set by platforms having multiple clock-domains, i.e.
295 * supporting multiple policies. With this sysfs directories of governor would
296 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same
297 * governor with different tunables for different clusters.
299 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3)
302 * Driver will do POSTCHANGE notifications from outside of their ->target()
303 * routine and so must set cpufreq_driver->flags with this flag, so that core
304 * can handle them specially.
306 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4)
309 * Set by drivers which want cpufreq core to check if CPU is running at a
310 * frequency present in freq-table exposed by the driver. For these drivers if
311 * CPU is found running at an out of table freq, we will try to set it to a freq
312 * from the table. And if that fails, we will stop further boot process by
313 * issuing a BUG_ON().
315 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5)
317 int cpufreq_register_driver(struct cpufreq_driver
*driver_data
);
318 int cpufreq_unregister_driver(struct cpufreq_driver
*driver_data
);
320 const char *cpufreq_get_current_driver(void);
321 void *cpufreq_get_driver_data(void);
323 static inline void cpufreq_verify_within_limits(struct cpufreq_policy
*policy
,
324 unsigned int min
, unsigned int max
)
326 if (policy
->min
< min
)
328 if (policy
->max
< min
)
330 if (policy
->min
> max
)
332 if (policy
->max
> max
)
334 if (policy
->min
> policy
->max
)
335 policy
->min
= policy
->max
;
340 cpufreq_verify_within_cpu_limits(struct cpufreq_policy
*policy
)
342 cpufreq_verify_within_limits(policy
, policy
->cpuinfo
.min_freq
,
343 policy
->cpuinfo
.max_freq
);
346 #ifdef CONFIG_CPU_FREQ
347 void cpufreq_suspend(void);
348 void cpufreq_resume(void);
349 int cpufreq_generic_suspend(struct cpufreq_policy
*policy
);
351 static inline void cpufreq_suspend(void) {}
352 static inline void cpufreq_resume(void) {}
355 /*********************************************************************
356 * CPUFREQ NOTIFIER INTERFACE *
357 *********************************************************************/
359 #define CPUFREQ_TRANSITION_NOTIFIER (0)
360 #define CPUFREQ_POLICY_NOTIFIER (1)
362 /* Transition notifiers */
363 #define CPUFREQ_PRECHANGE (0)
364 #define CPUFREQ_POSTCHANGE (1)
366 /* Policy Notifiers */
367 #define CPUFREQ_ADJUST (0)
368 #define CPUFREQ_INCOMPATIBLE (1)
369 #define CPUFREQ_NOTIFY (2)
370 #define CPUFREQ_START (3)
371 #define CPUFREQ_CREATE_POLICY (4)
372 #define CPUFREQ_REMOVE_POLICY (5)
374 #ifdef CONFIG_CPU_FREQ
375 int cpufreq_register_notifier(struct notifier_block
*nb
, unsigned int list
);
376 int cpufreq_unregister_notifier(struct notifier_block
*nb
, unsigned int list
);
378 void cpufreq_freq_transition_begin(struct cpufreq_policy
*policy
,
379 struct cpufreq_freqs
*freqs
);
380 void cpufreq_freq_transition_end(struct cpufreq_policy
*policy
,
381 struct cpufreq_freqs
*freqs
, int transition_failed
);
383 #else /* CONFIG_CPU_FREQ */
384 static inline int cpufreq_register_notifier(struct notifier_block
*nb
,
389 static inline int cpufreq_unregister_notifier(struct notifier_block
*nb
,
394 #endif /* !CONFIG_CPU_FREQ */
397 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch
404 * new = old * mult / div
406 static inline unsigned long cpufreq_scale(unsigned long old
, u_int div
,
409 #if BITS_PER_LONG == 32
410 u64 result
= ((u64
) old
) * ((u64
) mult
);
412 return (unsigned long) result
;
414 #elif BITS_PER_LONG == 64
415 unsigned long result
= old
* ((u64
) mult
);
421 /*********************************************************************
422 * CPUFREQ GOVERNORS *
423 *********************************************************************/
426 * If (cpufreq_driver->target) exists, the ->governor decides what frequency
427 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these
428 * two generic policies are available:
430 #define CPUFREQ_POLICY_POWERSAVE (1)
431 #define CPUFREQ_POLICY_PERFORMANCE (2)
433 /* Governor Events */
434 #define CPUFREQ_GOV_START 1
435 #define CPUFREQ_GOV_STOP 2
436 #define CPUFREQ_GOV_LIMITS 3
437 #define CPUFREQ_GOV_POLICY_INIT 4
438 #define CPUFREQ_GOV_POLICY_EXIT 5
440 struct cpufreq_governor
{
441 char name
[CPUFREQ_NAME_LEN
];
443 int (*governor
) (struct cpufreq_policy
*policy
,
445 ssize_t (*show_setspeed
) (struct cpufreq_policy
*policy
,
447 int (*store_setspeed
) (struct cpufreq_policy
*policy
,
449 unsigned int max_transition_latency
; /* HW must be able to switch to
450 next freq faster than this value in nano secs or we
451 will fallback to performance governor */
452 struct list_head governor_list
;
453 struct module
*owner
;
456 /* Pass a target to the cpufreq driver */
457 int cpufreq_driver_target(struct cpufreq_policy
*policy
,
458 unsigned int target_freq
,
459 unsigned int relation
);
460 int __cpufreq_driver_target(struct cpufreq_policy
*policy
,
461 unsigned int target_freq
,
462 unsigned int relation
);
463 int cpufreq_register_governor(struct cpufreq_governor
*governor
);
464 void cpufreq_unregister_governor(struct cpufreq_governor
*governor
);
466 /* CPUFREQ DEFAULT GOVERNOR */
468 * Performance governor is fallback governor if any other gov failed to auto
469 * load due latency restrictions
471 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE
472 extern struct cpufreq_governor cpufreq_gov_performance
;
474 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
475 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance)
476 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE)
477 extern struct cpufreq_governor cpufreq_gov_powersave
;
478 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave)
479 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
480 extern struct cpufreq_governor cpufreq_gov_userspace
;
481 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace)
482 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND)
483 extern struct cpufreq_governor cpufreq_gov_ondemand
;
484 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand)
485 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE)
486 extern struct cpufreq_governor cpufreq_gov_conservative
;
487 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative)
490 /*********************************************************************
491 * FREQUENCY TABLE HELPERS *
492 *********************************************************************/
494 /* Special Values of .frequency field */
495 #define CPUFREQ_ENTRY_INVALID ~0u
496 #define CPUFREQ_TABLE_END ~1u
497 /* Special Values of .flags field */
498 #define CPUFREQ_BOOST_FREQ (1 << 0)
500 struct cpufreq_frequency_table
{
502 unsigned int driver_data
; /* driver specific data, not used by core */
503 unsigned int frequency
; /* kHz - doesn't need to be in ascending
507 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP)
508 int dev_pm_opp_init_cpufreq_table(struct device
*dev
,
509 struct cpufreq_frequency_table
**table
);
510 void dev_pm_opp_free_cpufreq_table(struct device
*dev
,
511 struct cpufreq_frequency_table
**table
);
513 static inline int dev_pm_opp_init_cpufreq_table(struct device
*dev
,
514 struct cpufreq_frequency_table
520 static inline void dev_pm_opp_free_cpufreq_table(struct device
*dev
,
521 struct cpufreq_frequency_table
527 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table
**pos
)
529 while ((*pos
)->frequency
!= CPUFREQ_TABLE_END
)
530 if ((*pos
)->frequency
!= CPUFREQ_ENTRY_INVALID
)
538 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table
539 * @pos: the cpufreq_frequency_table * to use as a loop cursor.
540 * @table: the cpufreq_frequency_table * to iterate over.
543 #define cpufreq_for_each_entry(pos, table) \
544 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)
547 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table
548 * excluding CPUFREQ_ENTRY_INVALID frequencies.
549 * @pos: the cpufreq_frequency_table * to use as a loop cursor.
550 * @table: the cpufreq_frequency_table * to iterate over.
553 #define cpufreq_for_each_valid_entry(pos, table) \
554 for (pos = table; cpufreq_next_valid(&pos); pos++)
556 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy
*policy
,
557 struct cpufreq_frequency_table
*table
);
559 int cpufreq_frequency_table_verify(struct cpufreq_policy
*policy
,
560 struct cpufreq_frequency_table
*table
);
561 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy
*policy
);
563 int cpufreq_frequency_table_target(struct cpufreq_policy
*policy
,
564 struct cpufreq_frequency_table
*table
,
565 unsigned int target_freq
,
566 unsigned int relation
,
567 unsigned int *index
);
568 int cpufreq_frequency_table_get_index(struct cpufreq_policy
*policy
,
571 ssize_t
cpufreq_show_cpus(const struct cpumask
*mask
, char *buf
);
573 #ifdef CONFIG_CPU_FREQ
574 int cpufreq_boost_trigger_state(int state
);
575 int cpufreq_boost_supported(void);
576 int cpufreq_boost_enabled(void);
578 static inline int cpufreq_boost_trigger_state(int state
)
582 static inline int cpufreq_boost_supported(void)
586 static inline int cpufreq_boost_enabled(void)
591 /* the following funtion is for cpufreq core use only */
592 struct cpufreq_frequency_table
*cpufreq_frequency_get_table(unsigned int cpu
);
594 /* the following are really really optional */
595 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs
;
596 extern struct freq_attr
*cpufreq_generic_attr
[];
597 int cpufreq_table_validate_and_show(struct cpufreq_policy
*policy
,
598 struct cpufreq_frequency_table
*table
);
600 unsigned int cpufreq_generic_get(unsigned int cpu
);
601 int cpufreq_generic_init(struct cpufreq_policy
*policy
,
602 struct cpufreq_frequency_table
*table
,
603 unsigned int transition_latency
);
604 #endif /* _LINUX_CPUFREQ_H */