xref: /openbmc/linux/include/linux/cpufreq.h (revision 8bbecfb4)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * linux/include/linux/cpufreq.h
4  *
5  * Copyright (C) 2001 Russell King
6  *           (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
7  */
8 #ifndef _LINUX_CPUFREQ_H
9 #define _LINUX_CPUFREQ_H
10 
11 #include <linux/clk.h>
12 #include <linux/cpumask.h>
13 #include <linux/completion.h>
14 #include <linux/kobject.h>
15 #include <linux/notifier.h>
16 #include <linux/pm_qos.h>
17 #include <linux/spinlock.h>
18 #include <linux/sysfs.h>
19 
20 /*********************************************************************
21  *                        CPUFREQ INTERFACE                          *
22  *********************************************************************/
23 /*
24  * Frequency values here are CPU kHz
25  *
26  * Maximum transition latency is in nanoseconds - if it's unknown,
27  * CPUFREQ_ETERNAL shall be used.
28  */
29 
30 #define CPUFREQ_ETERNAL			(-1)
31 #define CPUFREQ_NAME_LEN		16
32 /* Print length for names. Extra 1 space for accommodating '\n' in prints */
33 #define CPUFREQ_NAME_PLEN		(CPUFREQ_NAME_LEN + 1)
34 
35 struct cpufreq_governor;
36 
37 enum cpufreq_table_sorting {
38 	CPUFREQ_TABLE_UNSORTED,
39 	CPUFREQ_TABLE_SORTED_ASCENDING,
40 	CPUFREQ_TABLE_SORTED_DESCENDING
41 };
42 
43 struct cpufreq_cpuinfo {
44 	unsigned int		max_freq;
45 	unsigned int		min_freq;
46 
47 	/* in 10^(-9) s = nanoseconds */
48 	unsigned int		transition_latency;
49 };
50 
51 struct cpufreq_policy {
52 	/* CPUs sharing clock, require sw coordination */
53 	cpumask_var_t		cpus;	/* Online CPUs only */
54 	cpumask_var_t		related_cpus; /* Online + Offline CPUs */
55 	cpumask_var_t		real_cpus; /* Related and present */
56 
57 	unsigned int		shared_type; /* ACPI: ANY or ALL affected CPUs
58 						should set cpufreq */
59 	unsigned int		cpu;    /* cpu managing this policy, must be online */
60 
61 	struct clk		*clk;
62 	struct cpufreq_cpuinfo	cpuinfo;/* see above */
63 
64 	unsigned int		min;    /* in kHz */
65 	unsigned int		max;    /* in kHz */
66 	unsigned int		cur;    /* in kHz, only needed if cpufreq
67 					 * governors are used */
68 	unsigned int		suspend_freq; /* freq to set during suspend */
69 
70 	unsigned int		policy; /* see above */
71 	unsigned int		last_policy; /* policy before unplug */
72 	struct cpufreq_governor	*governor; /* see below */
73 	void			*governor_data;
74 	char			last_governor[CPUFREQ_NAME_LEN]; /* last governor used */
75 
76 	struct work_struct	update; /* if update_policy() needs to be
77 					 * called, but you're in IRQ context */
78 
79 	struct freq_constraints	constraints;
80 	struct freq_qos_request	*min_freq_req;
81 	struct freq_qos_request	*max_freq_req;
82 
83 	struct cpufreq_frequency_table	*freq_table;
84 	enum cpufreq_table_sorting freq_table_sorted;
85 
86 	struct list_head        policy_list;
87 	struct kobject		kobj;
88 	struct completion	kobj_unregister;
89 
90 	/*
91 	 * The rules for this semaphore:
92 	 * - Any routine that wants to read from the policy structure will
93 	 *   do a down_read on this semaphore.
94 	 * - Any routine that will write to the policy structure and/or may take away
95 	 *   the policy altogether (eg. CPU hotplug), will hold this lock in write
96 	 *   mode before doing so.
97 	 */
98 	struct rw_semaphore	rwsem;
99 
100 	/*
101 	 * Fast switch flags:
102 	 * - fast_switch_possible should be set by the driver if it can
103 	 *   guarantee that frequency can be changed on any CPU sharing the
104 	 *   policy and that the change will affect all of the policy CPUs then.
105 	 * - fast_switch_enabled is to be set by governors that support fast
106 	 *   frequency switching with the help of cpufreq_enable_fast_switch().
107 	 */
108 	bool			fast_switch_possible;
109 	bool			fast_switch_enabled;
110 
111 	/*
112 	 * Set if the CPUFREQ_GOV_STRICT_TARGET flag is set for the current
113 	 * governor.
114 	 */
115 	bool			strict_target;
116 
117 	/*
118 	 * Preferred average time interval between consecutive invocations of
119 	 * the driver to set the frequency for this policy.  To be set by the
120 	 * scaling driver (0, which is the default, means no preference).
121 	 */
122 	unsigned int		transition_delay_us;
123 
124 	/*
125 	 * Remote DVFS flag (Not added to the driver structure as we don't want
126 	 * to access another structure from scheduler hotpath).
127 	 *
128 	 * Should be set if CPUs can do DVFS on behalf of other CPUs from
129 	 * different cpufreq policies.
130 	 */
131 	bool			dvfs_possible_from_any_cpu;
132 
133 	 /* Cached frequency lookup from cpufreq_driver_resolve_freq. */
134 	unsigned int cached_target_freq;
135 	unsigned int cached_resolved_idx;
136 
137 	/* Synchronization for frequency transitions */
138 	bool			transition_ongoing; /* Tracks transition status */
139 	spinlock_t		transition_lock;
140 	wait_queue_head_t	transition_wait;
141 	struct task_struct	*transition_task; /* Task which is doing the transition */
142 
143 	/* cpufreq-stats */
144 	struct cpufreq_stats	*stats;
145 
146 	/* For cpufreq driver's internal use */
147 	void			*driver_data;
148 
149 	/* Pointer to the cooling device if used for thermal mitigation */
150 	struct thermal_cooling_device *cdev;
151 
152 	struct notifier_block nb_min;
153 	struct notifier_block nb_max;
154 };
155 
156 /*
157  * Used for passing new cpufreq policy data to the cpufreq driver's ->verify()
158  * callback for sanitization.  That callback is only expected to modify the min
159  * and max values, if necessary, and specifically it must not update the
160  * frequency table.
161  */
162 struct cpufreq_policy_data {
163 	struct cpufreq_cpuinfo		cpuinfo;
164 	struct cpufreq_frequency_table	*freq_table;
165 	unsigned int			cpu;
166 	unsigned int			min;    /* in kHz */
167 	unsigned int			max;    /* in kHz */
168 };
169 
170 struct cpufreq_freqs {
171 	struct cpufreq_policy *policy;
172 	unsigned int old;
173 	unsigned int new;
174 	u8 flags;		/* flags of cpufreq_driver, see below. */
175 };
176 
177 /* Only for ACPI */
178 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */
179 #define CPUFREQ_SHARED_TYPE_HW	 (1) /* HW does needed coordination */
180 #define CPUFREQ_SHARED_TYPE_ALL	 (2) /* All dependent CPUs should set freq */
181 #define CPUFREQ_SHARED_TYPE_ANY	 (3) /* Freq can be set from any dependent CPU*/
182 
183 #ifdef CONFIG_CPU_FREQ
184 struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu);
185 struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu);
186 void cpufreq_cpu_put(struct cpufreq_policy *policy);
187 #else
188 static inline struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
189 {
190 	return NULL;
191 }
192 static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
193 {
194 	return NULL;
195 }
196 static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { }
197 #endif
198 
199 static inline bool policy_is_inactive(struct cpufreq_policy *policy)
200 {
201 	return cpumask_empty(policy->cpus);
202 }
203 
204 static inline bool policy_is_shared(struct cpufreq_policy *policy)
205 {
206 	return cpumask_weight(policy->cpus) > 1;
207 }
208 
209 #ifdef CONFIG_CPU_FREQ
210 unsigned int cpufreq_get(unsigned int cpu);
211 unsigned int cpufreq_quick_get(unsigned int cpu);
212 unsigned int cpufreq_quick_get_max(unsigned int cpu);
213 unsigned int cpufreq_get_hw_max_freq(unsigned int cpu);
214 void disable_cpufreq(void);
215 
216 u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy);
217 
218 struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu);
219 void cpufreq_cpu_release(struct cpufreq_policy *policy);
220 int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
221 void refresh_frequency_limits(struct cpufreq_policy *policy);
222 void cpufreq_update_policy(unsigned int cpu);
223 void cpufreq_update_limits(unsigned int cpu);
224 bool have_governor_per_policy(void);
225 bool cpufreq_supports_freq_invariance(void);
226 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);
227 void cpufreq_enable_fast_switch(struct cpufreq_policy *policy);
228 void cpufreq_disable_fast_switch(struct cpufreq_policy *policy);
229 #else
230 static inline unsigned int cpufreq_get(unsigned int cpu)
231 {
232 	return 0;
233 }
234 static inline unsigned int cpufreq_quick_get(unsigned int cpu)
235 {
236 	return 0;
237 }
238 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
239 {
240 	return 0;
241 }
242 static inline unsigned int cpufreq_get_hw_max_freq(unsigned int cpu)
243 {
244 	return 0;
245 }
246 static inline bool cpufreq_supports_freq_invariance(void)
247 {
248 	return false;
249 }
250 static inline void disable_cpufreq(void) { }
251 #endif
252 
253 #ifdef CONFIG_CPU_FREQ_STAT
254 void cpufreq_stats_create_table(struct cpufreq_policy *policy);
255 void cpufreq_stats_free_table(struct cpufreq_policy *policy);
256 void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
257 				     unsigned int new_freq);
258 #else
259 static inline void cpufreq_stats_create_table(struct cpufreq_policy *policy) { }
260 static inline void cpufreq_stats_free_table(struct cpufreq_policy *policy) { }
261 static inline void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
262 						   unsigned int new_freq) { }
263 #endif /* CONFIG_CPU_FREQ_STAT */
264 
265 /*********************************************************************
266  *                      CPUFREQ DRIVER INTERFACE                     *
267  *********************************************************************/
268 
269 #define CPUFREQ_RELATION_L 0  /* lowest frequency at or above target */
270 #define CPUFREQ_RELATION_H 1  /* highest frequency below or at target */
271 #define CPUFREQ_RELATION_C 2  /* closest frequency to target */
272 
273 struct freq_attr {
274 	struct attribute attr;
275 	ssize_t (*show)(struct cpufreq_policy *, char *);
276 	ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count);
277 };
278 
279 #define cpufreq_freq_attr_ro(_name)		\
280 static struct freq_attr _name =			\
281 __ATTR(_name, 0444, show_##_name, NULL)
282 
283 #define cpufreq_freq_attr_ro_perm(_name, _perm)	\
284 static struct freq_attr _name =			\
285 __ATTR(_name, _perm, show_##_name, NULL)
286 
287 #define cpufreq_freq_attr_rw(_name)		\
288 static struct freq_attr _name =			\
289 __ATTR(_name, 0644, show_##_name, store_##_name)
290 
291 #define cpufreq_freq_attr_wo(_name)		\
292 static struct freq_attr _name =			\
293 __ATTR(_name, 0200, NULL, store_##_name)
294 
295 #define define_one_global_ro(_name)		\
296 static struct kobj_attribute _name =		\
297 __ATTR(_name, 0444, show_##_name, NULL)
298 
299 #define define_one_global_rw(_name)		\
300 static struct kobj_attribute _name =		\
301 __ATTR(_name, 0644, show_##_name, store_##_name)
302 
303 
304 struct cpufreq_driver {
305 	char		name[CPUFREQ_NAME_LEN];
306 	u16		flags;
307 	void		*driver_data;
308 
309 	/* needed by all drivers */
310 	int		(*init)(struct cpufreq_policy *policy);
311 	int		(*verify)(struct cpufreq_policy_data *policy);
312 
313 	/* define one out of two */
314 	int		(*setpolicy)(struct cpufreq_policy *policy);
315 
316 	int		(*target)(struct cpufreq_policy *policy,
317 				  unsigned int target_freq,
318 				  unsigned int relation);	/* Deprecated */
319 	int		(*target_index)(struct cpufreq_policy *policy,
320 					unsigned int index);
321 	unsigned int	(*fast_switch)(struct cpufreq_policy *policy,
322 				       unsigned int target_freq);
323 	/*
324 	 * ->fast_switch() replacement for drivers that use an internal
325 	 * representation of performance levels and can pass hints other than
326 	 * the target performance level to the hardware.
327 	 */
328 	void		(*adjust_perf)(unsigned int cpu,
329 				       unsigned long min_perf,
330 				       unsigned long target_perf,
331 				       unsigned long capacity);
332 
333 	/*
334 	 * Caches and returns the lowest driver-supported frequency greater than
335 	 * or equal to the target frequency, subject to any driver limitations.
336 	 * Does not set the frequency. Only to be implemented for drivers with
337 	 * target().
338 	 */
339 	unsigned int	(*resolve_freq)(struct cpufreq_policy *policy,
340 					unsigned int target_freq);
341 
342 	/*
343 	 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION
344 	 * unset.
345 	 *
346 	 * get_intermediate should return a stable intermediate frequency
347 	 * platform wants to switch to and target_intermediate() should set CPU
348 	 * to that frequency, before jumping to the frequency corresponding
349 	 * to 'index'. Core will take care of sending notifications and driver
350 	 * doesn't have to handle them in target_intermediate() or
351 	 * target_index().
352 	 *
353 	 * Drivers can return '0' from get_intermediate() in case they don't
354 	 * wish to switch to intermediate frequency for some target frequency.
355 	 * In that case core will directly call ->target_index().
356 	 */
357 	unsigned int	(*get_intermediate)(struct cpufreq_policy *policy,
358 					    unsigned int index);
359 	int		(*target_intermediate)(struct cpufreq_policy *policy,
360 					       unsigned int index);
361 
362 	/* should be defined, if possible */
363 	unsigned int	(*get)(unsigned int cpu);
364 
365 	/* Called to update policy limits on firmware notifications. */
366 	void		(*update_limits)(unsigned int cpu);
367 
368 	/* optional */
369 	int		(*bios_limit)(int cpu, unsigned int *limit);
370 
371 	int		(*online)(struct cpufreq_policy *policy);
372 	int		(*offline)(struct cpufreq_policy *policy);
373 	int		(*exit)(struct cpufreq_policy *policy);
374 	void		(*stop_cpu)(struct cpufreq_policy *policy);
375 	int		(*suspend)(struct cpufreq_policy *policy);
376 	int		(*resume)(struct cpufreq_policy *policy);
377 
378 	/* Will be called after the driver is fully initialized */
379 	void		(*ready)(struct cpufreq_policy *policy);
380 
381 	struct freq_attr **attr;
382 
383 	/* platform specific boost support code */
384 	bool		boost_enabled;
385 	int		(*set_boost)(struct cpufreq_policy *policy, int state);
386 };
387 
388 /* flags */
389 
390 /*
391  * Set by drivers that need to update internale upper and lower boundaries along
392  * with the target frequency and so the core and governors should also invoke
393  * the diver if the target frequency does not change, but the policy min or max
394  * may have changed.
395  */
396 #define CPUFREQ_NEED_UPDATE_LIMITS		BIT(0)
397 
398 /* loops_per_jiffy or other kernel "constants" aren't affected by frequency transitions */
399 #define CPUFREQ_CONST_LOOPS			BIT(1)
400 
401 /*
402  * Set by drivers that want the core to automatically register the cpufreq
403  * driver as a thermal cooling device.
404  */
405 #define CPUFREQ_IS_COOLING_DEV			BIT(2)
406 
407 /*
408  * This should be set by platforms having multiple clock-domains, i.e.
409  * supporting multiple policies. With this sysfs directories of governor would
410  * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same
411  * governor with different tunables for different clusters.
412  */
413 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY	BIT(3)
414 
415 /*
416  * Driver will do POSTCHANGE notifications from outside of their ->target()
417  * routine and so must set cpufreq_driver->flags with this flag, so that core
418  * can handle them specially.
419  */
420 #define CPUFREQ_ASYNC_NOTIFICATION		BIT(4)
421 
422 /*
423  * Set by drivers which want cpufreq core to check if CPU is running at a
424  * frequency present in freq-table exposed by the driver. For these drivers if
425  * CPU is found running at an out of table freq, we will try to set it to a freq
426  * from the table. And if that fails, we will stop further boot process by
427  * issuing a BUG_ON().
428  */
429 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK	BIT(5)
430 
431 /*
432  * Set by drivers to disallow use of governors with "dynamic_switching" flag
433  * set.
434  */
435 #define CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING	BIT(6)
436 
437 int cpufreq_register_driver(struct cpufreq_driver *driver_data);
438 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data);
439 
440 bool cpufreq_driver_test_flags(u16 flags);
441 const char *cpufreq_get_current_driver(void);
442 void *cpufreq_get_driver_data(void);
443 
444 static inline int cpufreq_thermal_control_enabled(struct cpufreq_driver *drv)
445 {
446 	return IS_ENABLED(CONFIG_CPU_THERMAL) &&
447 		(drv->flags & CPUFREQ_IS_COOLING_DEV);
448 }
449 
450 static inline void cpufreq_verify_within_limits(struct cpufreq_policy_data *policy,
451 						unsigned int min,
452 						unsigned int max)
453 {
454 	if (policy->min < min)
455 		policy->min = min;
456 	if (policy->max < min)
457 		policy->max = min;
458 	if (policy->min > max)
459 		policy->min = max;
460 	if (policy->max > max)
461 		policy->max = max;
462 	if (policy->min > policy->max)
463 		policy->min = policy->max;
464 	return;
465 }
466 
467 static inline void
468 cpufreq_verify_within_cpu_limits(struct cpufreq_policy_data *policy)
469 {
470 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
471 				     policy->cpuinfo.max_freq);
472 }
473 
474 #ifdef CONFIG_CPU_FREQ
475 void cpufreq_suspend(void);
476 void cpufreq_resume(void);
477 int cpufreq_generic_suspend(struct cpufreq_policy *policy);
478 #else
479 static inline void cpufreq_suspend(void) {}
480 static inline void cpufreq_resume(void) {}
481 #endif
482 
483 /*********************************************************************
484  *                     CPUFREQ NOTIFIER INTERFACE                    *
485  *********************************************************************/
486 
487 #define CPUFREQ_TRANSITION_NOTIFIER	(0)
488 #define CPUFREQ_POLICY_NOTIFIER		(1)
489 
490 /* Transition notifiers */
491 #define CPUFREQ_PRECHANGE		(0)
492 #define CPUFREQ_POSTCHANGE		(1)
493 
494 /* Policy Notifiers  */
495 #define CPUFREQ_CREATE_POLICY		(0)
496 #define CPUFREQ_REMOVE_POLICY		(1)
497 
498 #ifdef CONFIG_CPU_FREQ
499 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);
500 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);
501 
502 void cpufreq_freq_transition_begin(struct cpufreq_policy *policy,
503 		struct cpufreq_freqs *freqs);
504 void cpufreq_freq_transition_end(struct cpufreq_policy *policy,
505 		struct cpufreq_freqs *freqs, int transition_failed);
506 
507 #else /* CONFIG_CPU_FREQ */
508 static inline int cpufreq_register_notifier(struct notifier_block *nb,
509 						unsigned int list)
510 {
511 	return 0;
512 }
513 static inline int cpufreq_unregister_notifier(struct notifier_block *nb,
514 						unsigned int list)
515 {
516 	return 0;
517 }
518 #endif /* !CONFIG_CPU_FREQ */
519 
520 /**
521  * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch
522  * safe)
523  * @old:   old value
524  * @div:   divisor
525  * @mult:  multiplier
526  *
527  *
528  * new = old * mult / div
529  */
530 static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
531 		u_int mult)
532 {
533 #if BITS_PER_LONG == 32
534 	u64 result = ((u64) old) * ((u64) mult);
535 	do_div(result, div);
536 	return (unsigned long) result;
537 
538 #elif BITS_PER_LONG == 64
539 	unsigned long result = old * ((u64) mult);
540 	result /= div;
541 	return result;
542 #endif
543 }
544 
545 /*********************************************************************
546  *                          CPUFREQ GOVERNORS                        *
547  *********************************************************************/
548 
549 #define CPUFREQ_POLICY_UNKNOWN		(0)
550 /*
551  * If (cpufreq_driver->target) exists, the ->governor decides what frequency
552  * within the limits is used. If (cpufreq_driver->setpolicy> exists, these
553  * two generic policies are available:
554  */
555 #define CPUFREQ_POLICY_POWERSAVE	(1)
556 #define CPUFREQ_POLICY_PERFORMANCE	(2)
557 
558 /*
559  * The polling frequency depends on the capability of the processor. Default
560  * polling frequency is 1000 times the transition latency of the processor. The
561  * ondemand governor will work on any processor with transition latency <= 10ms,
562  * using appropriate sampling rate.
563  */
564 #define LATENCY_MULTIPLIER		(1000)
565 
566 struct cpufreq_governor {
567 	char	name[CPUFREQ_NAME_LEN];
568 	int	(*init)(struct cpufreq_policy *policy);
569 	void	(*exit)(struct cpufreq_policy *policy);
570 	int	(*start)(struct cpufreq_policy *policy);
571 	void	(*stop)(struct cpufreq_policy *policy);
572 	void	(*limits)(struct cpufreq_policy *policy);
573 	ssize_t	(*show_setspeed)	(struct cpufreq_policy *policy,
574 					 char *buf);
575 	int	(*store_setspeed)	(struct cpufreq_policy *policy,
576 					 unsigned int freq);
577 	struct list_head	governor_list;
578 	struct module		*owner;
579 	u8			flags;
580 };
581 
582 /* Governor flags */
583 
584 /* For governors which change frequency dynamically by themselves */
585 #define CPUFREQ_GOV_DYNAMIC_SWITCHING	BIT(0)
586 
587 /* For governors wanting the target frequency to be set exactly */
588 #define CPUFREQ_GOV_STRICT_TARGET	BIT(1)
589 
590 
591 /* Pass a target to the cpufreq driver */
592 unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,
593 					unsigned int target_freq);
594 void cpufreq_driver_adjust_perf(unsigned int cpu,
595 				unsigned long min_perf,
596 				unsigned long target_perf,
597 				unsigned long capacity);
598 bool cpufreq_driver_has_adjust_perf(void);
599 int cpufreq_driver_target(struct cpufreq_policy *policy,
600 				 unsigned int target_freq,
601 				 unsigned int relation);
602 int __cpufreq_driver_target(struct cpufreq_policy *policy,
603 				   unsigned int target_freq,
604 				   unsigned int relation);
605 unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy,
606 					 unsigned int target_freq);
607 unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy);
608 int cpufreq_register_governor(struct cpufreq_governor *governor);
609 void cpufreq_unregister_governor(struct cpufreq_governor *governor);
610 int cpufreq_start_governor(struct cpufreq_policy *policy);
611 void cpufreq_stop_governor(struct cpufreq_policy *policy);
612 
613 #define cpufreq_governor_init(__governor)			\
614 static int __init __governor##_init(void)			\
615 {								\
616 	return cpufreq_register_governor(&__governor);	\
617 }								\
618 core_initcall(__governor##_init)
619 
620 #define cpufreq_governor_exit(__governor)			\
621 static void __exit __governor##_exit(void)			\
622 {								\
623 	return cpufreq_unregister_governor(&__governor);	\
624 }								\
625 module_exit(__governor##_exit)
626 
627 struct cpufreq_governor *cpufreq_default_governor(void);
628 struct cpufreq_governor *cpufreq_fallback_governor(void);
629 
630 static inline void cpufreq_policy_apply_limits(struct cpufreq_policy *policy)
631 {
632 	if (policy->max < policy->cur)
633 		__cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H);
634 	else if (policy->min > policy->cur)
635 		__cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L);
636 }
637 
638 /* Governor attribute set */
639 struct gov_attr_set {
640 	struct kobject kobj;
641 	struct list_head policy_list;
642 	struct mutex update_lock;
643 	int usage_count;
644 };
645 
646 /* sysfs ops for cpufreq governors */
647 extern const struct sysfs_ops governor_sysfs_ops;
648 
649 void gov_attr_set_init(struct gov_attr_set *attr_set, struct list_head *list_node);
650 void gov_attr_set_get(struct gov_attr_set *attr_set, struct list_head *list_node);
651 unsigned int gov_attr_set_put(struct gov_attr_set *attr_set, struct list_head *list_node);
652 
653 /* Governor sysfs attribute */
654 struct governor_attr {
655 	struct attribute attr;
656 	ssize_t (*show)(struct gov_attr_set *attr_set, char *buf);
657 	ssize_t (*store)(struct gov_attr_set *attr_set, const char *buf,
658 			 size_t count);
659 };
660 
661 /*********************************************************************
662  *                     FREQUENCY TABLE HELPERS                       *
663  *********************************************************************/
664 
665 /* Special Values of .frequency field */
666 #define CPUFREQ_ENTRY_INVALID	~0u
667 #define CPUFREQ_TABLE_END	~1u
668 /* Special Values of .flags field */
669 #define CPUFREQ_BOOST_FREQ	(1 << 0)
670 
671 struct cpufreq_frequency_table {
672 	unsigned int	flags;
673 	unsigned int	driver_data; /* driver specific data, not used by core */
674 	unsigned int	frequency; /* kHz - doesn't need to be in ascending
675 				    * order */
676 };
677 
678 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP)
679 int dev_pm_opp_init_cpufreq_table(struct device *dev,
680 				  struct cpufreq_frequency_table **table);
681 void dev_pm_opp_free_cpufreq_table(struct device *dev,
682 				   struct cpufreq_frequency_table **table);
683 #else
684 static inline int dev_pm_opp_init_cpufreq_table(struct device *dev,
685 						struct cpufreq_frequency_table
686 						**table)
687 {
688 	return -EINVAL;
689 }
690 
691 static inline void dev_pm_opp_free_cpufreq_table(struct device *dev,
692 						 struct cpufreq_frequency_table
693 						 **table)
694 {
695 }
696 #endif
697 
698 /*
699  * cpufreq_for_each_entry -	iterate over a cpufreq_frequency_table
700  * @pos:	the cpufreq_frequency_table * to use as a loop cursor.
701  * @table:	the cpufreq_frequency_table * to iterate over.
702  */
703 
704 #define cpufreq_for_each_entry(pos, table)	\
705 	for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)
706 
707 /*
708  * cpufreq_for_each_entry_idx -	iterate over a cpufreq_frequency_table
709  *	with index
710  * @pos:	the cpufreq_frequency_table * to use as a loop cursor.
711  * @table:	the cpufreq_frequency_table * to iterate over.
712  * @idx:	the table entry currently being processed
713  */
714 
715 #define cpufreq_for_each_entry_idx(pos, table, idx)	\
716 	for (pos = table, idx = 0; pos->frequency != CPUFREQ_TABLE_END; \
717 		pos++, idx++)
718 
719 /*
720  * cpufreq_for_each_valid_entry -     iterate over a cpufreq_frequency_table
721  *	excluding CPUFREQ_ENTRY_INVALID frequencies.
722  * @pos:        the cpufreq_frequency_table * to use as a loop cursor.
723  * @table:      the cpufreq_frequency_table * to iterate over.
724  */
725 
726 #define cpufreq_for_each_valid_entry(pos, table)			\
727 	for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)	\
728 		if (pos->frequency == CPUFREQ_ENTRY_INVALID)		\
729 			continue;					\
730 		else
731 
732 /*
733  * cpufreq_for_each_valid_entry_idx -     iterate with index over a cpufreq
734  *	frequency_table excluding CPUFREQ_ENTRY_INVALID frequencies.
735  * @pos:	the cpufreq_frequency_table * to use as a loop cursor.
736  * @table:	the cpufreq_frequency_table * to iterate over.
737  * @idx:	the table entry currently being processed
738  */
739 
740 #define cpufreq_for_each_valid_entry_idx(pos, table, idx)		\
741 	cpufreq_for_each_entry_idx(pos, table, idx)			\
742 		if (pos->frequency == CPUFREQ_ENTRY_INVALID)		\
743 			continue;					\
744 		else
745 
746 
747 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
748 				    struct cpufreq_frequency_table *table);
749 
750 int cpufreq_frequency_table_verify(struct cpufreq_policy_data *policy,
751 				   struct cpufreq_frequency_table *table);
752 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy_data *policy);
753 
754 int cpufreq_table_index_unsorted(struct cpufreq_policy *policy,
755 				 unsigned int target_freq,
756 				 unsigned int relation);
757 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
758 		unsigned int freq);
759 
760 ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf);
761 
762 #ifdef CONFIG_CPU_FREQ
763 int cpufreq_boost_trigger_state(int state);
764 int cpufreq_boost_enabled(void);
765 int cpufreq_enable_boost_support(void);
766 bool policy_has_boost_freq(struct cpufreq_policy *policy);
767 
768 /* Find lowest freq at or above target in a table in ascending order */
769 static inline int cpufreq_table_find_index_al(struct cpufreq_policy *policy,
770 					      unsigned int target_freq)
771 {
772 	struct cpufreq_frequency_table *table = policy->freq_table;
773 	struct cpufreq_frequency_table *pos;
774 	unsigned int freq;
775 	int idx, best = -1;
776 
777 	cpufreq_for_each_valid_entry_idx(pos, table, idx) {
778 		freq = pos->frequency;
779 
780 		if (freq >= target_freq)
781 			return idx;
782 
783 		best = idx;
784 	}
785 
786 	return best;
787 }
788 
789 /* Find lowest freq at or above target in a table in descending order */
790 static inline int cpufreq_table_find_index_dl(struct cpufreq_policy *policy,
791 					      unsigned int target_freq)
792 {
793 	struct cpufreq_frequency_table *table = policy->freq_table;
794 	struct cpufreq_frequency_table *pos;
795 	unsigned int freq;
796 	int idx, best = -1;
797 
798 	cpufreq_for_each_valid_entry_idx(pos, table, idx) {
799 		freq = pos->frequency;
800 
801 		if (freq == target_freq)
802 			return idx;
803 
804 		if (freq > target_freq) {
805 			best = idx;
806 			continue;
807 		}
808 
809 		/* No freq found above target_freq */
810 		if (best == -1)
811 			return idx;
812 
813 		return best;
814 	}
815 
816 	return best;
817 }
818 
819 /* Works only on sorted freq-tables */
820 static inline int cpufreq_table_find_index_l(struct cpufreq_policy *policy,
821 					     unsigned int target_freq)
822 {
823 	target_freq = clamp_val(target_freq, policy->min, policy->max);
824 
825 	if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING)
826 		return cpufreq_table_find_index_al(policy, target_freq);
827 	else
828 		return cpufreq_table_find_index_dl(policy, target_freq);
829 }
830 
831 /* Find highest freq at or below target in a table in ascending order */
832 static inline int cpufreq_table_find_index_ah(struct cpufreq_policy *policy,
833 					      unsigned int target_freq)
834 {
835 	struct cpufreq_frequency_table *table = policy->freq_table;
836 	struct cpufreq_frequency_table *pos;
837 	unsigned int freq;
838 	int idx, best = -1;
839 
840 	cpufreq_for_each_valid_entry_idx(pos, table, idx) {
841 		freq = pos->frequency;
842 
843 		if (freq == target_freq)
844 			return idx;
845 
846 		if (freq < target_freq) {
847 			best = idx;
848 			continue;
849 		}
850 
851 		/* No freq found below target_freq */
852 		if (best == -1)
853 			return idx;
854 
855 		return best;
856 	}
857 
858 	return best;
859 }
860 
861 /* Find highest freq at or below target in a table in descending order */
862 static inline int cpufreq_table_find_index_dh(struct cpufreq_policy *policy,
863 					      unsigned int target_freq)
864 {
865 	struct cpufreq_frequency_table *table = policy->freq_table;
866 	struct cpufreq_frequency_table *pos;
867 	unsigned int freq;
868 	int idx, best = -1;
869 
870 	cpufreq_for_each_valid_entry_idx(pos, table, idx) {
871 		freq = pos->frequency;
872 
873 		if (freq <= target_freq)
874 			return idx;
875 
876 		best = idx;
877 	}
878 
879 	return best;
880 }
881 
882 /* Works only on sorted freq-tables */
883 static inline int cpufreq_table_find_index_h(struct cpufreq_policy *policy,
884 					     unsigned int target_freq)
885 {
886 	target_freq = clamp_val(target_freq, policy->min, policy->max);
887 
888 	if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING)
889 		return cpufreq_table_find_index_ah(policy, target_freq);
890 	else
891 		return cpufreq_table_find_index_dh(policy, target_freq);
892 }
893 
894 /* Find closest freq to target in a table in ascending order */
895 static inline int cpufreq_table_find_index_ac(struct cpufreq_policy *policy,
896 					      unsigned int target_freq)
897 {
898 	struct cpufreq_frequency_table *table = policy->freq_table;
899 	struct cpufreq_frequency_table *pos;
900 	unsigned int freq;
901 	int idx, best = -1;
902 
903 	cpufreq_for_each_valid_entry_idx(pos, table, idx) {
904 		freq = pos->frequency;
905 
906 		if (freq == target_freq)
907 			return idx;
908 
909 		if (freq < target_freq) {
910 			best = idx;
911 			continue;
912 		}
913 
914 		/* No freq found below target_freq */
915 		if (best == -1)
916 			return idx;
917 
918 		/* Choose the closest freq */
919 		if (target_freq - table[best].frequency > freq - target_freq)
920 			return idx;
921 
922 		return best;
923 	}
924 
925 	return best;
926 }
927 
928 /* Find closest freq to target in a table in descending order */
929 static inline int cpufreq_table_find_index_dc(struct cpufreq_policy *policy,
930 					      unsigned int target_freq)
931 {
932 	struct cpufreq_frequency_table *table = policy->freq_table;
933 	struct cpufreq_frequency_table *pos;
934 	unsigned int freq;
935 	int idx, best = -1;
936 
937 	cpufreq_for_each_valid_entry_idx(pos, table, idx) {
938 		freq = pos->frequency;
939 
940 		if (freq == target_freq)
941 			return idx;
942 
943 		if (freq > target_freq) {
944 			best = idx;
945 			continue;
946 		}
947 
948 		/* No freq found above target_freq */
949 		if (best == -1)
950 			return idx;
951 
952 		/* Choose the closest freq */
953 		if (table[best].frequency - target_freq > target_freq - freq)
954 			return idx;
955 
956 		return best;
957 	}
958 
959 	return best;
960 }
961 
962 /* Works only on sorted freq-tables */
963 static inline int cpufreq_table_find_index_c(struct cpufreq_policy *policy,
964 					     unsigned int target_freq)
965 {
966 	target_freq = clamp_val(target_freq, policy->min, policy->max);
967 
968 	if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING)
969 		return cpufreq_table_find_index_ac(policy, target_freq);
970 	else
971 		return cpufreq_table_find_index_dc(policy, target_freq);
972 }
973 
974 static inline int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
975 						 unsigned int target_freq,
976 						 unsigned int relation)
977 {
978 	if (unlikely(policy->freq_table_sorted == CPUFREQ_TABLE_UNSORTED))
979 		return cpufreq_table_index_unsorted(policy, target_freq,
980 						    relation);
981 
982 	switch (relation) {
983 	case CPUFREQ_RELATION_L:
984 		return cpufreq_table_find_index_l(policy, target_freq);
985 	case CPUFREQ_RELATION_H:
986 		return cpufreq_table_find_index_h(policy, target_freq);
987 	case CPUFREQ_RELATION_C:
988 		return cpufreq_table_find_index_c(policy, target_freq);
989 	default:
990 		WARN_ON_ONCE(1);
991 		return 0;
992 	}
993 }
994 
995 static inline int cpufreq_table_count_valid_entries(const struct cpufreq_policy *policy)
996 {
997 	struct cpufreq_frequency_table *pos;
998 	int count = 0;
999 
1000 	if (unlikely(!policy->freq_table))
1001 		return 0;
1002 
1003 	cpufreq_for_each_valid_entry(pos, policy->freq_table)
1004 		count++;
1005 
1006 	return count;
1007 }
1008 #else
1009 static inline int cpufreq_boost_trigger_state(int state)
1010 {
1011 	return 0;
1012 }
1013 static inline int cpufreq_boost_enabled(void)
1014 {
1015 	return 0;
1016 }
1017 
1018 static inline int cpufreq_enable_boost_support(void)
1019 {
1020 	return -EINVAL;
1021 }
1022 
1023 static inline bool policy_has_boost_freq(struct cpufreq_policy *policy)
1024 {
1025 	return false;
1026 }
1027 #endif
1028 
1029 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
1030 void sched_cpufreq_governor_change(struct cpufreq_policy *policy,
1031 			struct cpufreq_governor *old_gov);
1032 #else
1033 static inline void sched_cpufreq_governor_change(struct cpufreq_policy *policy,
1034 			struct cpufreq_governor *old_gov) { }
1035 #endif
1036 
1037 extern void arch_freq_prepare_all(void);
1038 extern unsigned int arch_freq_get_on_cpu(int cpu);
1039 
1040 #ifndef arch_set_freq_scale
1041 static __always_inline
1042 void arch_set_freq_scale(const struct cpumask *cpus,
1043 			 unsigned long cur_freq,
1044 			 unsigned long max_freq)
1045 {
1046 }
1047 #endif
1048 
1049 /* the following are really really optional */
1050 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
1051 extern struct freq_attr cpufreq_freq_attr_scaling_boost_freqs;
1052 extern struct freq_attr *cpufreq_generic_attr[];
1053 int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy);
1054 
1055 unsigned int cpufreq_generic_get(unsigned int cpu);
1056 void cpufreq_generic_init(struct cpufreq_policy *policy,
1057 		struct cpufreq_frequency_table *table,
1058 		unsigned int transition_latency);
1059 #endif /* _LINUX_CPUFREQ_H */
1060