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/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_user_policy { 55 unsigned int min; /* in kHz */ 56 unsigned int max; /* in kHz */ 57 }; 58 59 struct cpufreq_policy { 60 /* CPUs sharing clock, require sw coordination */ 61 cpumask_var_t cpus; /* Online CPUs only */ 62 cpumask_var_t related_cpus; /* Online + Offline CPUs */ 63 cpumask_var_t real_cpus; /* Related and present */ 64 65 unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs 66 should set cpufreq */ 67 unsigned int cpu; /* cpu managing this policy, must be online */ 68 69 struct clk *clk; 70 struct cpufreq_cpuinfo cpuinfo;/* see above */ 71 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 */ 78 79 unsigned int policy; /* see above */ 80 unsigned int last_policy; /* policy before unplug */ 81 struct cpufreq_governor *governor; /* see below */ 82 void *governor_data; 83 bool governor_enabled; /* governor start/stop flag */ 84 char last_governor[CPUFREQ_NAME_LEN]; /* last governor used */ 85 86 struct work_struct update; /* if update_policy() needs to be 87 * called, but you're in IRQ context */ 88 89 struct cpufreq_user_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 /* cpufreq-stats */ 117 struct cpufreq_stats *stats; 118 119 /* For cpufreq driver's internal use */ 120 void *driver_data; 121 }; 122 123 /* Only for ACPI */ 124 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ 125 #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ 126 #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ 127 #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ 128 129 #ifdef CONFIG_CPU_FREQ 130 struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu); 131 struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); 132 void cpufreq_cpu_put(struct cpufreq_policy *policy); 133 #else 134 static inline struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) 135 { 136 return NULL; 137 } 138 static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) 139 { 140 return NULL; 141 } 142 static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { } 143 #endif 144 145 static inline bool policy_is_shared(struct cpufreq_policy *policy) 146 { 147 return cpumask_weight(policy->cpus) > 1; 148 } 149 150 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */ 151 extern struct kobject *cpufreq_global_kobject; 152 153 #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); 158 159 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); 164 #else 165 static inline unsigned int cpufreq_get(unsigned int cpu) 166 { 167 return 0; 168 } 169 static inline unsigned int cpufreq_quick_get(unsigned int cpu) 170 { 171 return 0; 172 } 173 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) 174 { 175 return 0; 176 } 177 static inline void disable_cpufreq(void) { } 178 #endif 179 180 /********************************************************************* 181 * CPUFREQ DRIVER INTERFACE * 182 *********************************************************************/ 183 184 #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 */ 187 188 struct freq_attr { 189 struct attribute attr; 190 ssize_t (*show)(struct cpufreq_policy *, char *); 191 ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); 192 }; 193 194 #define cpufreq_freq_attr_ro(_name) \ 195 static struct freq_attr _name = \ 196 __ATTR(_name, 0444, show_##_name, NULL) 197 198 #define cpufreq_freq_attr_ro_perm(_name, _perm) \ 199 static struct freq_attr _name = \ 200 __ATTR(_name, _perm, show_##_name, NULL) 201 202 #define cpufreq_freq_attr_rw(_name) \ 203 static struct freq_attr _name = \ 204 __ATTR(_name, 0644, show_##_name, store_##_name) 205 206 struct global_attr { 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); 212 }; 213 214 #define define_one_global_ro(_name) \ 215 static struct global_attr _name = \ 216 __ATTR(_name, 0444, show_##_name, NULL) 217 218 #define define_one_global_rw(_name) \ 219 static struct global_attr _name = \ 220 __ATTR(_name, 0644, show_##_name, store_##_name) 221 222 223 struct cpufreq_driver { 224 char name[CPUFREQ_NAME_LEN]; 225 u8 flags; 226 void *driver_data; 227 228 /* needed by all drivers */ 229 int (*init)(struct cpufreq_policy *policy); 230 int (*verify)(struct cpufreq_policy *policy); 231 232 /* define one out of two */ 233 int (*setpolicy)(struct cpufreq_policy *policy); 234 235 /* 236 * On failure, should always restore frequency to policy->restore_freq 237 * (i.e. old freq). 238 */ 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, 243 unsigned int index); 244 /* 245 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION 246 * unset. 247 * 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 253 * target_index(). 254 * 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(). 258 */ 259 unsigned int (*get_intermediate)(struct cpufreq_policy *policy, 260 unsigned int index); 261 int (*target_intermediate)(struct cpufreq_policy *policy, 262 unsigned int index); 263 264 /* should be defined, if possible */ 265 unsigned int (*get)(unsigned int cpu); 266 267 /* optional */ 268 int (*bios_limit)(int cpu, unsigned int *limit); 269 270 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); 274 275 /* Will be called after the driver is fully initialized */ 276 void (*ready)(struct cpufreq_policy *policy); 277 278 struct freq_attr **attr; 279 280 /* platform specific boost support code */ 281 bool boost_enabled; 282 int (*set_boost)(int state); 283 }; 284 285 /* flags */ 286 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if 287 all ->init() calls failed */ 288 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other 289 kernel "constants" aren't 290 affected by frequency 291 transitions */ 292 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume 293 speed mismatches */ 294 295 /* 296 * This should be set by platforms having multiple clock-domains, i.e. 297 * supporting multiple policies. With this sysfs directories of governor would 298 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same 299 * governor with different tunables for different clusters. 300 */ 301 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) 302 303 /* 304 * Driver will do POSTCHANGE notifications from outside of their ->target() 305 * routine and so must set cpufreq_driver->flags with this flag, so that core 306 * can handle them specially. 307 */ 308 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) 309 310 /* 311 * Set by drivers which want cpufreq core to check if CPU is running at a 312 * frequency present in freq-table exposed by the driver. For these drivers if 313 * CPU is found running at an out of table freq, we will try to set it to a freq 314 * from the table. And if that fails, we will stop further boot process by 315 * issuing a BUG_ON(). 316 */ 317 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5) 318 319 int cpufreq_register_driver(struct cpufreq_driver *driver_data); 320 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 321 322 const char *cpufreq_get_current_driver(void); 323 void *cpufreq_get_driver_data(void); 324 325 static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, 326 unsigned int min, unsigned int max) 327 { 328 if (policy->min < min) 329 policy->min = min; 330 if (policy->max < min) 331 policy->max = min; 332 if (policy->min > max) 333 policy->min = max; 334 if (policy->max > max) 335 policy->max = max; 336 if (policy->min > policy->max) 337 policy->min = policy->max; 338 return; 339 } 340 341 static inline void 342 cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) 343 { 344 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, 345 policy->cpuinfo.max_freq); 346 } 347 348 #ifdef CONFIG_CPU_FREQ 349 void cpufreq_suspend(void); 350 void cpufreq_resume(void); 351 int cpufreq_generic_suspend(struct cpufreq_policy *policy); 352 #else 353 static inline void cpufreq_suspend(void) {} 354 static inline void cpufreq_resume(void) {} 355 #endif 356 357 /********************************************************************* 358 * CPUFREQ NOTIFIER INTERFACE * 359 *********************************************************************/ 360 361 #define CPUFREQ_TRANSITION_NOTIFIER (0) 362 #define CPUFREQ_POLICY_NOTIFIER (1) 363 364 /* Transition notifiers */ 365 #define CPUFREQ_PRECHANGE (0) 366 #define CPUFREQ_POSTCHANGE (1) 367 368 /* Policy Notifiers */ 369 #define CPUFREQ_ADJUST (0) 370 #define CPUFREQ_NOTIFY (1) 371 #define CPUFREQ_START (2) 372 #define CPUFREQ_CREATE_POLICY (3) 373 #define CPUFREQ_REMOVE_POLICY (4) 374 375 #ifdef CONFIG_CPU_FREQ 376 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); 377 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); 378 379 void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, 380 struct cpufreq_freqs *freqs); 381 void cpufreq_freq_transition_end(struct cpufreq_policy *policy, 382 struct cpufreq_freqs *freqs, int transition_failed); 383 384 #else /* CONFIG_CPU_FREQ */ 385 static inline int cpufreq_register_notifier(struct notifier_block *nb, 386 unsigned int list) 387 { 388 return 0; 389 } 390 static inline int cpufreq_unregister_notifier(struct notifier_block *nb, 391 unsigned int list) 392 { 393 return 0; 394 } 395 #endif /* !CONFIG_CPU_FREQ */ 396 397 /** 398 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch 399 * safe) 400 * @old: old value 401 * @div: divisor 402 * @mult: multiplier 403 * 404 * 405 * new = old * mult / div 406 */ 407 static inline unsigned long cpufreq_scale(unsigned long old, u_int div, 408 u_int mult) 409 { 410 #if BITS_PER_LONG == 32 411 u64 result = ((u64) old) * ((u64) mult); 412 do_div(result, div); 413 return (unsigned long) result; 414 415 #elif BITS_PER_LONG == 64 416 unsigned long result = old * ((u64) mult); 417 result /= div; 418 return result; 419 #endif 420 } 421 422 /********************************************************************* 423 * CPUFREQ GOVERNORS * 424 *********************************************************************/ 425 426 /* 427 * If (cpufreq_driver->target) exists, the ->governor decides what frequency 428 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these 429 * two generic policies are available: 430 */ 431 #define CPUFREQ_POLICY_POWERSAVE (1) 432 #define CPUFREQ_POLICY_PERFORMANCE (2) 433 434 /* Governor Events */ 435 #define CPUFREQ_GOV_START 1 436 #define CPUFREQ_GOV_STOP 2 437 #define CPUFREQ_GOV_LIMITS 3 438 #define CPUFREQ_GOV_POLICY_INIT 4 439 #define CPUFREQ_GOV_POLICY_EXIT 5 440 441 struct cpufreq_governor { 442 char name[CPUFREQ_NAME_LEN]; 443 int initialized; 444 int (*governor) (struct cpufreq_policy *policy, 445 unsigned int event); 446 ssize_t (*show_setspeed) (struct cpufreq_policy *policy, 447 char *buf); 448 int (*store_setspeed) (struct cpufreq_policy *policy, 449 unsigned int freq); 450 unsigned int max_transition_latency; /* HW must be able to switch to 451 next freq faster than this value in nano secs or we 452 will fallback to performance governor */ 453 struct list_head governor_list; 454 struct module *owner; 455 }; 456 457 /* Pass a target to the cpufreq driver */ 458 int cpufreq_driver_target(struct cpufreq_policy *policy, 459 unsigned int target_freq, 460 unsigned int relation); 461 int __cpufreq_driver_target(struct cpufreq_policy *policy, 462 unsigned int target_freq, 463 unsigned int relation); 464 int cpufreq_register_governor(struct cpufreq_governor *governor); 465 void cpufreq_unregister_governor(struct cpufreq_governor *governor); 466 467 /* CPUFREQ DEFAULT GOVERNOR */ 468 /* 469 * Performance governor is fallback governor if any other gov failed to auto 470 * load due latency restrictions 471 */ 472 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE 473 extern struct cpufreq_governor cpufreq_gov_performance; 474 #endif 475 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE 476 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) 477 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) 478 extern struct cpufreq_governor cpufreq_gov_powersave; 479 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) 480 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) 481 extern struct cpufreq_governor cpufreq_gov_userspace; 482 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) 483 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) 484 extern struct cpufreq_governor cpufreq_gov_ondemand; 485 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) 486 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) 487 extern struct cpufreq_governor cpufreq_gov_conservative; 488 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) 489 #endif 490 491 /********************************************************************* 492 * FREQUENCY TABLE HELPERS * 493 *********************************************************************/ 494 495 /* Special Values of .frequency field */ 496 #define CPUFREQ_ENTRY_INVALID ~0u 497 #define CPUFREQ_TABLE_END ~1u 498 /* Special Values of .flags field */ 499 #define CPUFREQ_BOOST_FREQ (1 << 0) 500 501 struct cpufreq_frequency_table { 502 unsigned int flags; 503 unsigned int driver_data; /* driver specific data, not used by core */ 504 unsigned int frequency; /* kHz - doesn't need to be in ascending 505 * order */ 506 }; 507 508 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) 509 int dev_pm_opp_init_cpufreq_table(struct device *dev, 510 struct cpufreq_frequency_table **table); 511 void dev_pm_opp_free_cpufreq_table(struct device *dev, 512 struct cpufreq_frequency_table **table); 513 #else 514 static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, 515 struct cpufreq_frequency_table 516 **table) 517 { 518 return -EINVAL; 519 } 520 521 static inline void dev_pm_opp_free_cpufreq_table(struct device *dev, 522 struct cpufreq_frequency_table 523 **table) 524 { 525 } 526 #endif 527 528 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table **pos) 529 { 530 while ((*pos)->frequency != CPUFREQ_TABLE_END) 531 if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID) 532 return true; 533 else 534 (*pos)++; 535 return false; 536 } 537 538 /* 539 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table 540 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 541 * @table: the cpufreq_frequency_table * to iterate over. 542 */ 543 544 #define cpufreq_for_each_entry(pos, table) \ 545 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++) 546 547 /* 548 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table 549 * excluding CPUFREQ_ENTRY_INVALID frequencies. 550 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 551 * @table: the cpufreq_frequency_table * to iterate over. 552 */ 553 554 #define cpufreq_for_each_valid_entry(pos, table) \ 555 for (pos = table; cpufreq_next_valid(&pos); pos++) 556 557 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 558 struct cpufreq_frequency_table *table); 559 560 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 561 struct cpufreq_frequency_table *table); 562 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy); 563 564 int cpufreq_frequency_table_target(struct cpufreq_policy *policy, 565 struct cpufreq_frequency_table *table, 566 unsigned int target_freq, 567 unsigned int relation, 568 unsigned int *index); 569 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, 570 unsigned int freq); 571 572 ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); 573 574 #ifdef CONFIG_CPU_FREQ 575 int cpufreq_boost_trigger_state(int state); 576 int cpufreq_boost_enabled(void); 577 int cpufreq_enable_boost_support(void); 578 bool policy_has_boost_freq(struct cpufreq_policy *policy); 579 #else 580 static inline int cpufreq_boost_trigger_state(int state) 581 { 582 return 0; 583 } 584 static inline int cpufreq_boost_enabled(void) 585 { 586 return 0; 587 } 588 589 static inline int cpufreq_enable_boost_support(void) 590 { 591 return -EINVAL; 592 } 593 594 static inline bool policy_has_boost_freq(struct cpufreq_policy *policy) 595 { 596 return false; 597 } 598 #endif 599 /* the following funtion is for cpufreq core use only */ 600 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); 601 602 /* the following are really really optional */ 603 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; 604 extern struct freq_attr cpufreq_freq_attr_scaling_boost_freqs; 605 extern struct freq_attr *cpufreq_generic_attr[]; 606 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy, 607 struct cpufreq_frequency_table *table); 608 609 unsigned int cpufreq_generic_get(unsigned int cpu); 610 int cpufreq_generic_init(struct cpufreq_policy *policy, 611 struct cpufreq_frequency_table *table, 612 unsigned int transition_latency); 613 #endif /* _LINUX_CPUFREQ_H */ 614