1 /* 2 * linux/include/linux/cpufreq.h 3 * 4 * Copyright (C) 2001 Russell King 5 * (C) 2002 - 2003 Dominik Brodowski <[email protected]> 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/spinlock.h> 20 #include <linux/sysfs.h> 21 22 /********************************************************************* 23 * CPUFREQ INTERFACE * 24 *********************************************************************/ 25 /* 26 * Frequency values here are CPU kHz 27 * 28 * Maximum transition latency is in nanoseconds - if it's unknown, 29 * CPUFREQ_ETERNAL shall be used. 30 */ 31 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) 36 37 struct cpufreq_governor; 38 39 struct cpufreq_freqs { 40 unsigned int cpu; /* cpu nr */ 41 unsigned int old; 42 unsigned int new; 43 u8 flags; /* flags of cpufreq_driver, see below. */ 44 }; 45 46 struct cpufreq_cpuinfo { 47 unsigned int max_freq; 48 unsigned int min_freq; 49 50 /* in 10^(-9) s = nanoseconds */ 51 unsigned int transition_latency; 52 }; 53 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 */ 59 }; 60 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 */ 65 66 unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs 67 should set cpufreq */ 68 unsigned int cpu; /* cpu nr of CPU managing this policy */ 69 unsigned int last_cpu; /* cpu nr of previous CPU that managed 70 * this policy */ 71 struct clk *clk; 72 struct cpufreq_cpuinfo cpuinfo;/* see above */ 73 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 */ 80 81 unsigned int policy; /* see above */ 82 struct cpufreq_governor *governor; /* see below */ 83 void *governor_data; 84 bool governor_enabled; /* governor start/stop flag */ 85 86 struct work_struct update; /* if update_policy() needs to be 87 * called, but you're in IRQ context */ 88 89 struct cpufreq_real_policy user_policy; 90 struct cpufreq_frequency_table *freq_table; 91 92 struct list_head policy_list; 93 struct kobject kobj; 94 struct completion kobj_unregister; 95 96 /* 97 * The rules for this semaphore: 98 * - Any routine that wants to read from the policy structure will 99 * do a down_read on this semaphore. 100 * - Any routine that will write to the policy structure and/or may take away 101 * the policy altogether (eg. CPU hotplug), will hold this lock in write 102 * mode before doing so. 103 * 104 * Additional rules: 105 * - Lock should not be held across 106 * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); 107 */ 108 struct rw_semaphore rwsem; 109 110 /* Synchronization for frequency transitions */ 111 bool transition_ongoing; /* Tracks transition status */ 112 spinlock_t transition_lock; 113 wait_queue_head_t transition_wait; 114 struct task_struct *transition_task; /* Task which is doing the transition */ 115 116 /* For cpufreq driver's internal use */ 117 void *driver_data; 118 }; 119 120 /* Only for ACPI */ 121 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ 122 #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ 123 #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ 124 #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ 125 126 #ifdef CONFIG_CPU_FREQ 127 struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); 128 void cpufreq_cpu_put(struct cpufreq_policy *policy); 129 #else 130 static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) 131 { 132 return NULL; 133 } 134 static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { } 135 #endif 136 137 static inline bool policy_is_shared(struct cpufreq_policy *policy) 138 { 139 return cpumask_weight(policy->cpus) > 1; 140 } 141 142 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */ 143 extern struct kobject *cpufreq_global_kobject; 144 int cpufreq_get_global_kobject(void); 145 void cpufreq_put_global_kobject(void); 146 int cpufreq_sysfs_create_file(const struct attribute *attr); 147 void cpufreq_sysfs_remove_file(const struct attribute *attr); 148 149 #ifdef CONFIG_CPU_FREQ 150 unsigned int cpufreq_get(unsigned int cpu); 151 unsigned int cpufreq_quick_get(unsigned int cpu); 152 unsigned int cpufreq_quick_get_max(unsigned int cpu); 153 void disable_cpufreq(void); 154 155 u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy); 156 int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); 157 int cpufreq_update_policy(unsigned int cpu); 158 bool have_governor_per_policy(void); 159 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); 160 #else 161 static inline unsigned int cpufreq_get(unsigned int cpu) 162 { 163 return 0; 164 } 165 static inline unsigned int cpufreq_quick_get(unsigned int cpu) 166 { 167 return 0; 168 } 169 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) 170 { 171 return 0; 172 } 173 static inline void disable_cpufreq(void) { } 174 #endif 175 176 /********************************************************************* 177 * CPUFREQ DRIVER INTERFACE * 178 *********************************************************************/ 179 180 #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ 181 #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ 182 #define CPUFREQ_RELATION_C 2 /* closest frequency to target */ 183 184 struct freq_attr { 185 struct attribute attr; 186 ssize_t (*show)(struct cpufreq_policy *, char *); 187 ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); 188 }; 189 190 #define cpufreq_freq_attr_ro(_name) \ 191 static struct freq_attr _name = \ 192 __ATTR(_name, 0444, show_##_name, NULL) 193 194 #define cpufreq_freq_attr_ro_perm(_name, _perm) \ 195 static struct freq_attr _name = \ 196 __ATTR(_name, _perm, show_##_name, NULL) 197 198 #define cpufreq_freq_attr_rw(_name) \ 199 static struct freq_attr _name = \ 200 __ATTR(_name, 0644, show_##_name, store_##_name) 201 202 struct global_attr { 203 struct attribute attr; 204 ssize_t (*show)(struct kobject *kobj, 205 struct attribute *attr, char *buf); 206 ssize_t (*store)(struct kobject *a, struct attribute *b, 207 const char *c, size_t count); 208 }; 209 210 #define define_one_global_ro(_name) \ 211 static struct global_attr _name = \ 212 __ATTR(_name, 0444, show_##_name, NULL) 213 214 #define define_one_global_rw(_name) \ 215 static struct global_attr _name = \ 216 __ATTR(_name, 0644, show_##_name, store_##_name) 217 218 219 struct cpufreq_driver { 220 char name[CPUFREQ_NAME_LEN]; 221 u8 flags; 222 223 /* needed by all drivers */ 224 int (*init) (struct cpufreq_policy *policy); 225 int (*verify) (struct cpufreq_policy *policy); 226 227 /* define one out of two */ 228 int (*setpolicy) (struct cpufreq_policy *policy); 229 230 /* 231 * On failure, should always restore frequency to policy->restore_freq 232 * (i.e. old freq). 233 */ 234 int (*target) (struct cpufreq_policy *policy, /* Deprecated */ 235 unsigned int target_freq, 236 unsigned int relation); 237 int (*target_index) (struct cpufreq_policy *policy, 238 unsigned int index); 239 /* 240 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION 241 * unset. 242 * 243 * get_intermediate should return a stable intermediate frequency 244 * platform wants to switch to and target_intermediate() should set CPU 245 * to to that frequency, before jumping to the frequency corresponding 246 * to 'index'. Core will take care of sending notifications and driver 247 * doesn't have to handle them in target_intermediate() or 248 * target_index(). 249 * 250 * Drivers can return '0' from get_intermediate() in case they don't 251 * wish to switch to intermediate frequency for some target frequency. 252 * In that case core will directly call ->target_index(). 253 */ 254 unsigned int (*get_intermediate)(struct cpufreq_policy *policy, 255 unsigned int index); 256 int (*target_intermediate)(struct cpufreq_policy *policy, 257 unsigned int index); 258 259 /* should be defined, if possible */ 260 unsigned int (*get) (unsigned int cpu); 261 262 /* optional */ 263 int (*bios_limit) (int cpu, unsigned int *limit); 264 265 int (*exit) (struct cpufreq_policy *policy); 266 void (*stop_cpu) (struct cpufreq_policy *policy); 267 int (*suspend) (struct cpufreq_policy *policy); 268 int (*resume) (struct cpufreq_policy *policy); 269 struct freq_attr **attr; 270 271 /* platform specific boost support code */ 272 bool boost_supported; 273 bool boost_enabled; 274 int (*set_boost) (int state); 275 }; 276 277 /* flags */ 278 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if 279 all ->init() calls failed */ 280 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other 281 kernel "constants" aren't 282 affected by frequency 283 transitions */ 284 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume 285 speed mismatches */ 286 287 /* 288 * This should be set by platforms having multiple clock-domains, i.e. 289 * supporting multiple policies. With this sysfs directories of governor would 290 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same 291 * governor with different tunables for different clusters. 292 */ 293 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) 294 295 /* 296 * Driver will do POSTCHANGE notifications from outside of their ->target() 297 * routine and so must set cpufreq_driver->flags with this flag, so that core 298 * can handle them specially. 299 */ 300 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) 301 302 /* 303 * Set by drivers which want cpufreq core to check if CPU is running at a 304 * frequency present in freq-table exposed by the driver. For these drivers if 305 * CPU is found running at an out of table freq, we will try to set it to a freq 306 * from the table. And if that fails, we will stop further boot process by 307 * issuing a BUG_ON(). 308 */ 309 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5) 310 311 int cpufreq_register_driver(struct cpufreq_driver *driver_data); 312 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 313 314 const char *cpufreq_get_current_driver(void); 315 316 static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, 317 unsigned int min, unsigned int max) 318 { 319 if (policy->min < min) 320 policy->min = min; 321 if (policy->max < min) 322 policy->max = min; 323 if (policy->min > max) 324 policy->min = max; 325 if (policy->max > max) 326 policy->max = max; 327 if (policy->min > policy->max) 328 policy->min = policy->max; 329 return; 330 } 331 332 static inline void 333 cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) 334 { 335 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, 336 policy->cpuinfo.max_freq); 337 } 338 339 #ifdef CONFIG_CPU_FREQ 340 void cpufreq_suspend(void); 341 void cpufreq_resume(void); 342 int cpufreq_generic_suspend(struct cpufreq_policy *policy); 343 #else 344 static inline void cpufreq_suspend(void) {} 345 static inline void cpufreq_resume(void) {} 346 #endif 347 348 /********************************************************************* 349 * CPUFREQ NOTIFIER INTERFACE * 350 *********************************************************************/ 351 352 #define CPUFREQ_TRANSITION_NOTIFIER (0) 353 #define CPUFREQ_POLICY_NOTIFIER (1) 354 355 /* Transition notifiers */ 356 #define CPUFREQ_PRECHANGE (0) 357 #define CPUFREQ_POSTCHANGE (1) 358 359 /* Policy Notifiers */ 360 #define CPUFREQ_ADJUST (0) 361 #define CPUFREQ_INCOMPATIBLE (1) 362 #define CPUFREQ_NOTIFY (2) 363 #define CPUFREQ_START (3) 364 #define CPUFREQ_UPDATE_POLICY_CPU (4) 365 #define CPUFREQ_CREATE_POLICY (5) 366 #define CPUFREQ_REMOVE_POLICY (6) 367 368 #ifdef CONFIG_CPU_FREQ 369 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); 370 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); 371 372 void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, 373 struct cpufreq_freqs *freqs); 374 void cpufreq_freq_transition_end(struct cpufreq_policy *policy, 375 struct cpufreq_freqs *freqs, int transition_failed); 376 377 #else /* CONFIG_CPU_FREQ */ 378 static inline int cpufreq_register_notifier(struct notifier_block *nb, 379 unsigned int list) 380 { 381 return 0; 382 } 383 static inline int cpufreq_unregister_notifier(struct notifier_block *nb, 384 unsigned int list) 385 { 386 return 0; 387 } 388 #endif /* !CONFIG_CPU_FREQ */ 389 390 /** 391 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch 392 * safe) 393 * @old: old value 394 * @div: divisor 395 * @mult: multiplier 396 * 397 * 398 * new = old * mult / div 399 */ 400 static inline unsigned long cpufreq_scale(unsigned long old, u_int div, 401 u_int mult) 402 { 403 #if BITS_PER_LONG == 32 404 u64 result = ((u64) old) * ((u64) mult); 405 do_div(result, div); 406 return (unsigned long) result; 407 408 #elif BITS_PER_LONG == 64 409 unsigned long result = old * ((u64) mult); 410 result /= div; 411 return result; 412 #endif 413 } 414 415 /********************************************************************* 416 * CPUFREQ GOVERNORS * 417 *********************************************************************/ 418 419 /* 420 * If (cpufreq_driver->target) exists, the ->governor decides what frequency 421 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these 422 * two generic policies are available: 423 */ 424 #define CPUFREQ_POLICY_POWERSAVE (1) 425 #define CPUFREQ_POLICY_PERFORMANCE (2) 426 427 /* Governor Events */ 428 #define CPUFREQ_GOV_START 1 429 #define CPUFREQ_GOV_STOP 2 430 #define CPUFREQ_GOV_LIMITS 3 431 #define CPUFREQ_GOV_POLICY_INIT 4 432 #define CPUFREQ_GOV_POLICY_EXIT 5 433 434 struct cpufreq_governor { 435 char name[CPUFREQ_NAME_LEN]; 436 int initialized; 437 int (*governor) (struct cpufreq_policy *policy, 438 unsigned int event); 439 ssize_t (*show_setspeed) (struct cpufreq_policy *policy, 440 char *buf); 441 int (*store_setspeed) (struct cpufreq_policy *policy, 442 unsigned int freq); 443 unsigned int max_transition_latency; /* HW must be able to switch to 444 next freq faster than this value in nano secs or we 445 will fallback to performance governor */ 446 struct list_head governor_list; 447 struct module *owner; 448 }; 449 450 /* Pass a target to the cpufreq driver */ 451 int cpufreq_driver_target(struct cpufreq_policy *policy, 452 unsigned int target_freq, 453 unsigned int relation); 454 int __cpufreq_driver_target(struct cpufreq_policy *policy, 455 unsigned int target_freq, 456 unsigned int relation); 457 int cpufreq_register_governor(struct cpufreq_governor *governor); 458 void cpufreq_unregister_governor(struct cpufreq_governor *governor); 459 460 /* CPUFREQ DEFAULT GOVERNOR */ 461 /* 462 * Performance governor is fallback governor if any other gov failed to auto 463 * load due latency restrictions 464 */ 465 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE 466 extern struct cpufreq_governor cpufreq_gov_performance; 467 #endif 468 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE 469 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) 470 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) 471 extern struct cpufreq_governor cpufreq_gov_powersave; 472 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) 473 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) 474 extern struct cpufreq_governor cpufreq_gov_userspace; 475 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) 476 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) 477 extern struct cpufreq_governor cpufreq_gov_ondemand; 478 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) 479 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) 480 extern struct cpufreq_governor cpufreq_gov_conservative; 481 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) 482 #endif 483 484 /********************************************************************* 485 * FREQUENCY TABLE HELPERS * 486 *********************************************************************/ 487 488 /* Special Values of .frequency field */ 489 #define CPUFREQ_ENTRY_INVALID ~0u 490 #define CPUFREQ_TABLE_END ~1u 491 /* Special Values of .flags field */ 492 #define CPUFREQ_BOOST_FREQ (1 << 0) 493 494 struct cpufreq_frequency_table { 495 unsigned int flags; 496 unsigned int driver_data; /* driver specific data, not used by core */ 497 unsigned int frequency; /* kHz - doesn't need to be in ascending 498 * order */ 499 }; 500 501 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) 502 int dev_pm_opp_init_cpufreq_table(struct device *dev, 503 struct cpufreq_frequency_table **table); 504 void dev_pm_opp_free_cpufreq_table(struct device *dev, 505 struct cpufreq_frequency_table **table); 506 #else 507 static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, 508 struct cpufreq_frequency_table 509 **table) 510 { 511 return -EINVAL; 512 } 513 514 static inline void dev_pm_opp_free_cpufreq_table(struct device *dev, 515 struct cpufreq_frequency_table 516 **table) 517 { 518 } 519 #endif 520 521 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table **pos) 522 { 523 while ((*pos)->frequency != CPUFREQ_TABLE_END) 524 if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID) 525 return true; 526 else 527 (*pos)++; 528 return false; 529 } 530 531 /* 532 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table 533 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 534 * @table: the cpufreq_frequency_table * to iterate over. 535 */ 536 537 #define cpufreq_for_each_entry(pos, table) \ 538 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++) 539 540 /* 541 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table 542 * excluding CPUFREQ_ENTRY_INVALID frequencies. 543 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 544 * @table: the cpufreq_frequency_table * to iterate over. 545 */ 546 547 #define cpufreq_for_each_valid_entry(pos, table) \ 548 for (pos = table; cpufreq_next_valid(&pos); pos++) 549 550 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 551 struct cpufreq_frequency_table *table); 552 553 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 554 struct cpufreq_frequency_table *table); 555 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy); 556 557 int cpufreq_frequency_table_target(struct cpufreq_policy *policy, 558 struct cpufreq_frequency_table *table, 559 unsigned int target_freq, 560 unsigned int relation, 561 unsigned int *index); 562 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, 563 unsigned int freq); 564 565 ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); 566 567 #ifdef CONFIG_CPU_FREQ 568 int cpufreq_boost_trigger_state(int state); 569 int cpufreq_boost_supported(void); 570 int cpufreq_boost_enabled(void); 571 #else 572 static inline int cpufreq_boost_trigger_state(int state) 573 { 574 return 0; 575 } 576 static inline int cpufreq_boost_supported(void) 577 { 578 return 0; 579 } 580 static inline int cpufreq_boost_enabled(void) 581 { 582 return 0; 583 } 584 #endif 585 /* the following funtion is for cpufreq core use only */ 586 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); 587 588 /* the following are really really optional */ 589 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; 590 extern struct freq_attr *cpufreq_generic_attr[]; 591 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy, 592 struct cpufreq_frequency_table *table); 593 594 unsigned int cpufreq_generic_get(unsigned int cpu); 595 int cpufreq_generic_init(struct cpufreq_policy *policy, 596 struct cpufreq_frequency_table *table, 597 unsigned int transition_latency); 598 #endif /* _LINUX_CPUFREQ_H */ 599