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