/include/linux/cpufreq.h
C++ Header | 442 lines | 273 code | 92 blank | 77 comment | 7 complexity | 62ea9d1cd448da75fea51a9f8848f8e7 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.0, AGPL-1.0
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/mutex.h> 15#include <linux/notifier.h> 16#include <linux/threads.h> 17#include <linux/device.h> 18#include <linux/kobject.h> 19#include <linux/sysfs.h> 20#include <linux/completion.h> 21#include <linux/workqueue.h> 22#include <linux/cpumask.h> 23#include <asm/div64.h> 24 25#define CPUFREQ_NAME_LEN 16 26 27 28/********************************************************************* 29 * CPUFREQ NOTIFIER INTERFACE * 30 *********************************************************************/ 31 32#define CPUFREQ_TRANSITION_NOTIFIER (0) 33#define CPUFREQ_POLICY_NOTIFIER (1) 34 35#ifdef CONFIG_CPU_FREQ 36int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); 37int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); 38#else /* CONFIG_CPU_FREQ */ 39static inline int cpufreq_register_notifier(struct notifier_block *nb, 40 unsigned int list) 41{ 42 return 0; 43} 44static inline int cpufreq_unregister_notifier(struct notifier_block *nb, 45 unsigned int list) 46{ 47 return 0; 48} 49#endif /* CONFIG_CPU_FREQ */ 50 51/* if (cpufreq_driver->target) exists, the ->governor decides what frequency 52 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these 53 * two generic policies are available: 54 */ 55 56#define CPUFREQ_POLICY_POWERSAVE (1) 57#define CPUFREQ_POLICY_PERFORMANCE (2) 58 59/* Frequency values here are CPU kHz so that hardware which doesn't run 60 * with some frequencies can complain without having to guess what per 61 * cent / per mille means. 62 * Maximum transition latency is in nanoseconds - if it's unknown, 63 * CPUFREQ_ETERNAL shall be used. 64 */ 65 66struct cpufreq_governor; 67 68/* /sys/devices/system/cpu/cpufreq: entry point for global variables */ 69extern struct kobject *cpufreq_global_kobject; 70 71#define CPUFREQ_ETERNAL (-1) 72struct cpufreq_cpuinfo { 73 unsigned int max_freq; 74 unsigned int min_freq; 75 unsigned int transition_latency; /* in 10^(-9) s = nanoseconds */ 76}; 77 78struct cpufreq_real_policy { 79 unsigned int min; /* in kHz */ 80 unsigned int max; /* in kHz */ 81 unsigned int policy; /* see above */ 82 struct cpufreq_governor *governor; /* see below */ 83}; 84 85struct cpufreq_policy { 86 cpumask_var_t cpus; /* CPUs requiring sw coordination */ 87 cpumask_var_t related_cpus; /* CPUs with any coordination */ 88 unsigned int shared_type; /* ANY or ALL affected CPUs 89 should set cpufreq */ 90 unsigned int cpu; /* cpu nr of registered CPU */ 91 struct cpufreq_cpuinfo cpuinfo;/* see above */ 92 93 unsigned int min; /* in kHz */ 94 unsigned int max; /* in kHz */ 95 unsigned int cur; /* in kHz, only needed if cpufreq 96 * governors are used */ 97 unsigned int policy; /* see above */ 98 struct cpufreq_governor *governor; /* see below */ 99 100 struct work_struct update; /* if update_policy() needs to be 101 * called, but you're in IRQ context */ 102 103 struct cpufreq_real_policy user_policy; 104 105 struct kobject kobj; 106 struct completion kobj_unregister; 107}; 108 109#define CPUFREQ_ADJUST (0) 110#define CPUFREQ_INCOMPATIBLE (1) 111#define CPUFREQ_NOTIFY (2) 112#define CPUFREQ_START (3) 113 114#define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ 115#define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ 116#define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ 117#define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ 118 119/******************** cpufreq transition notifiers *******************/ 120 121#define CPUFREQ_PRECHANGE (0) 122#define CPUFREQ_POSTCHANGE (1) 123#define CPUFREQ_RESUMECHANGE (8) 124#define CPUFREQ_SUSPENDCHANGE (9) 125 126struct cpufreq_freqs { 127 unsigned int cpu; /* cpu nr */ 128 unsigned int old; 129 unsigned int new; 130 u8 flags; /* flags of cpufreq_driver, see below. */ 131}; 132 133 134/** 135 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch safe) 136 * @old: old value 137 * @div: divisor 138 * @mult: multiplier 139 * 140 * 141 * new = old * mult / div 142 */ 143static inline unsigned long cpufreq_scale(unsigned long old, u_int div, u_int mult) 144{ 145#if BITS_PER_LONG == 32 146 147 u64 result = ((u64) old) * ((u64) mult); 148 do_div(result, div); 149 return (unsigned long) result; 150 151#elif BITS_PER_LONG == 64 152 153 unsigned long result = old * ((u64) mult); 154 result /= div; 155 return result; 156 157#endif 158}; 159 160/********************************************************************* 161 * CPUFREQ GOVERNORS * 162 *********************************************************************/ 163 164#define CPUFREQ_GOV_START 1 165#define CPUFREQ_GOV_STOP 2 166#define CPUFREQ_GOV_LIMITS 3 167 168struct cpufreq_governor { 169 char name[CPUFREQ_NAME_LEN]; 170 int (*governor) (struct cpufreq_policy *policy, 171 unsigned int event); 172 ssize_t (*show_setspeed) (struct cpufreq_policy *policy, 173 char *buf); 174 int (*store_setspeed) (struct cpufreq_policy *policy, 175 unsigned int freq); 176 unsigned int max_transition_latency; /* HW must be able to switch to 177 next freq faster than this value in nano secs or we 178 will fallback to performance governor */ 179 struct list_head governor_list; 180 struct module *owner; 181}; 182 183/* pass a target to the cpufreq driver 184 */ 185extern int cpufreq_driver_target(struct cpufreq_policy *policy, 186 unsigned int target_freq, 187 unsigned int relation); 188extern int __cpufreq_driver_target(struct cpufreq_policy *policy, 189 unsigned int target_freq, 190 unsigned int relation); 191 192 193extern int __cpufreq_driver_getavg(struct cpufreq_policy *policy, 194 unsigned int cpu); 195 196int cpufreq_register_governor(struct cpufreq_governor *governor); 197void cpufreq_unregister_governor(struct cpufreq_governor *governor); 198 199int lock_policy_rwsem_read(int cpu); 200int lock_policy_rwsem_write(int cpu); 201void unlock_policy_rwsem_read(int cpu); 202void unlock_policy_rwsem_write(int cpu); 203 204 205/********************************************************************* 206 * CPUFREQ DRIVER INTERFACE * 207 *********************************************************************/ 208 209#define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ 210#define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ 211 212struct freq_attr; 213 214struct cpufreq_driver { 215 struct module *owner; 216 char name[CPUFREQ_NAME_LEN]; 217 u8 flags; 218 219 /* needed by all drivers */ 220 int (*init) (struct cpufreq_policy *policy); 221 int (*verify) (struct cpufreq_policy *policy); 222 223 /* define one out of two */ 224 int (*setpolicy) (struct cpufreq_policy *policy); 225 int (*target) (struct cpufreq_policy *policy, 226 unsigned int target_freq, 227 unsigned int relation); 228 229 /* should be defined, if possible */ 230 unsigned int (*get) (unsigned int cpu); 231 232 /* optional */ 233 unsigned int (*getavg) (struct cpufreq_policy *policy, 234 unsigned int cpu); 235 int (*bios_limit) (int cpu, unsigned int *limit); 236 237 int (*exit) (struct cpufreq_policy *policy); 238 int (*suspend) (struct cpufreq_policy *policy, pm_message_t pmsg); 239 int (*resume) (struct cpufreq_policy *policy); 240 struct freq_attr **attr; 241}; 242 243/* flags */ 244 245#define CPUFREQ_STICKY 0x01 /* the driver isn't removed even if 246 * all ->init() calls failed */ 247#define CPUFREQ_CONST_LOOPS 0x02 /* loops_per_jiffy or other kernel 248 * "constants" aren't affected by 249 * frequency transitions */ 250#define CPUFREQ_PM_NO_WARN 0x04 /* don't warn on suspend/resume speed 251 * mismatches */ 252 253int cpufreq_register_driver(struct cpufreq_driver *driver_data); 254int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 255 256 257void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state); 258 259 260static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, unsigned int min, unsigned int max) 261{ 262 if (policy->min < min) 263 policy->min = min; 264 if (policy->max < min) 265 policy->max = min; 266 if (policy->min > max) 267 policy->min = max; 268 if (policy->max > max) 269 policy->max = max; 270 if (policy->min > policy->max) 271 policy->min = policy->max; 272 return; 273} 274 275struct freq_attr { 276 struct attribute attr; 277 ssize_t (*show)(struct cpufreq_policy *, char *); 278 ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); 279}; 280 281#define cpufreq_freq_attr_ro(_name) \ 282static struct freq_attr _name = \ 283__ATTR(_name, 0444, show_##_name, NULL) 284 285#define cpufreq_freq_attr_ro_perm(_name, _perm) \ 286static struct freq_attr _name = \ 287__ATTR(_name, _perm, show_##_name, NULL) 288 289#define cpufreq_freq_attr_ro_old(_name) \ 290static struct freq_attr _name##_old = \ 291__ATTR(_name, 0444, show_##_name##_old, NULL) 292 293#define cpufreq_freq_attr_rw(_name) \ 294static struct freq_attr _name = \ 295__ATTR(_name, 0644, show_##_name, store_##_name) 296 297#define cpufreq_freq_attr_rw_old(_name) \ 298static struct freq_attr _name##_old = \ 299__ATTR(_name, 0644, show_##_name##_old, store_##_name##_old) 300 301 302struct global_attr { 303 struct attribute attr; 304 ssize_t (*show)(struct kobject *kobj, 305 struct attribute *attr, char *buf); 306 ssize_t (*store)(struct kobject *a, struct attribute *b, 307 const char *c, size_t count); 308}; 309 310#define define_one_global_ro(_name) \ 311static struct global_attr _name = \ 312__ATTR(_name, 0444, show_##_name, NULL) 313 314#define define_one_global_rw(_name) \ 315static struct global_attr _name = \ 316__ATTR(_name, 0644, show_##_name, store_##_name) 317 318 319/********************************************************************* 320 * CPUFREQ 2.6. INTERFACE * 321 *********************************************************************/ 322int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); 323int cpufreq_update_policy(unsigned int cpu); 324 325#ifdef CONFIG_CPU_FREQ 326/* query the current CPU frequency (in kHz). If zero, cpufreq couldn't detect it */ 327unsigned int cpufreq_get(unsigned int cpu); 328#else 329static inline unsigned int cpufreq_get(unsigned int cpu) 330{ 331 return 0; 332} 333#endif 334 335/* query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it */ 336#ifdef CONFIG_CPU_FREQ 337unsigned int cpufreq_quick_get(unsigned int cpu); 338#else 339static inline unsigned int cpufreq_quick_get(unsigned int cpu) 340{ 341 return 0; 342} 343#endif 344 345 346/********************************************************************* 347 * CPUFREQ DEFAULT GOVERNOR * 348 *********************************************************************/ 349 350 351/* 352 Performance governor is fallback governor if any other gov failed to 353 auto load due latency restrictions 354*/ 355#ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE 356extern struct cpufreq_governor cpufreq_gov_performance; 357#endif 358#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE 359#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) 360#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) 361extern struct cpufreq_governor cpufreq_gov_powersave; 362#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) 363#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) 364extern struct cpufreq_governor cpufreq_gov_userspace; 365#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) 366#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) 367extern struct cpufreq_governor cpufreq_gov_ondemand; 368#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) 369#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) 370extern struct cpufreq_governor cpufreq_gov_conservative; 371#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) 372#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_INTERACTIVE) 373extern struct cpufreq_governor cpufreq_gov_interactive; 374#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_interactive) 375#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_SMARTASS2) 376extern struct cpufreq_governor cpufreq_gov_smartass2; 377#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_smartass2) 378#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_MSM7K) 379extern struct cpufreq_governor cpufreq_gov_msm7k; 380#define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_msm7k) 381#endif 382 383 384/********************************************************************* 385 * FREQUENCY TABLE HELPERS * 386 *********************************************************************/ 387 388#define CPUFREQ_ENTRY_INVALID ~0 389#define CPUFREQ_TABLE_END ~1 390 391struct cpufreq_frequency_table { 392 unsigned int index; /* any */ 393 unsigned int frequency; /* kHz - doesn't need to be in ascending 394 * order */ 395}; 396 397int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 398 struct cpufreq_frequency_table *table); 399 400int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 401 struct cpufreq_frequency_table *table); 402 403int cpufreq_frequency_table_target(struct cpufreq_policy *policy, 404 struct cpufreq_frequency_table *table, 405 unsigned int target_freq, 406 unsigned int relation, 407 unsigned int *index); 408 409/* the following 3 funtions are for cpufreq core use only */ 410struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); 411struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); 412void cpufreq_cpu_put (struct cpufreq_policy *data); 413 414/* the following are really really optional */ 415extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; 416 417void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table, 418 unsigned int cpu); 419 420void cpufreq_frequency_table_put_attr(unsigned int cpu); 421 422 423/********************************************************************* 424 * UNIFIED DEBUG HELPERS * 425 *********************************************************************/ 426 427#define CPUFREQ_DEBUG_CORE 1 428#define CPUFREQ_DEBUG_DRIVER 2 429#define CPUFREQ_DEBUG_GOVERNOR 4 430 431#ifdef CONFIG_CPU_FREQ_DEBUG 432 433extern void cpufreq_debug_printk(unsigned int type, const char *prefix, 434 const char *fmt, ...); 435 436#else 437 438#define cpufreq_debug_printk(msg...) do { } while(0) 439 440#endif /* CONFIG_CPU_FREQ_DEBUG */ 441 442#endif /* _LINUX_CPUFREQ_H */