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_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 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 struct cpufreq_governor *governor; /* see below */ 81 void *governor_data; 82 bool governor_enabled; /* governor start/stop flag */ 83 84 struct work_struct update; /* if update_policy() needs to be 85 * called, but you're in IRQ context */ 86 87 struct cpufreq_real_policy user_policy; 88 struct cpufreq_frequency_table *freq_table; 89 90 struct list_head policy_list; 91 struct kobject kobj; 92 struct completion kobj_unregister; 93 94 /* 95 * The rules for this semaphore: 96 * - Any routine that wants to read from the policy structure will 97 * do a down_read on this semaphore. 98 * - Any routine that will write to the policy structure and/or may take away 99 * the policy altogether (eg. CPU hotplug), will hold this lock in write 100 * mode before doing so. 101 * 102 * Additional rules: 103 * - Lock should not be held across 104 * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); 105 */ 106 struct rw_semaphore rwsem; 107 108 /* Synchronization for frequency transitions */ 109 bool transition_ongoing; /* Tracks transition status */ 110 spinlock_t transition_lock; 111 wait_queue_head_t transition_wait; 112 struct task_struct *transition_task; /* Task which is doing the transition */ 113 114 /* cpufreq-stats */ 115 struct cpufreq_stats *stats; 116 117 /* For cpufreq driver's internal use */ 118 void *driver_data; 119 }; 120 121 /* Only for ACPI */ 122 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ 123 #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ 124 #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ 125 #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ 126 127 #ifdef CONFIG_CPU_FREQ 128 struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); 129 void cpufreq_cpu_put(struct cpufreq_policy *policy); 130 #else 131 static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) 132 { 133 return NULL; 134 } 135 static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { } 136 #endif 137 138 static inline bool policy_is_shared(struct cpufreq_policy *policy) 139 { 140 return cpumask_weight(policy->cpus) > 1; 141 } 142 143 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */ 144 extern struct kobject *cpufreq_global_kobject; 145 int cpufreq_get_global_kobject(void); 146 void cpufreq_put_global_kobject(void); 147 int cpufreq_sysfs_create_file(const struct attribute *attr); 148 void cpufreq_sysfs_remove_file(const struct attribute *attr); 149 150 #ifdef CONFIG_CPU_FREQ 151 unsigned int cpufreq_get(unsigned int cpu); 152 unsigned int cpufreq_quick_get(unsigned int cpu); 153 unsigned int cpufreq_quick_get_max(unsigned int cpu); 154 void disable_cpufreq(void); 155 156 u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy); 157 int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); 158 int cpufreq_update_policy(unsigned int cpu); 159 bool have_governor_per_policy(void); 160 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); 161 #else 162 static inline unsigned int cpufreq_get(unsigned int cpu) 163 { 164 return 0; 165 } 166 static inline unsigned int cpufreq_quick_get(unsigned int cpu) 167 { 168 return 0; 169 } 170 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) 171 { 172 return 0; 173 } 174 static inline void disable_cpufreq(void) { } 175 #endif 176 177 /********************************************************************* 178 * CPUFREQ DRIVER INTERFACE * 179 *********************************************************************/ 180 181 #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ 182 #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ 183 #define CPUFREQ_RELATION_C 2 /* closest frequency to target */ 184 185 struct freq_attr { 186 struct attribute attr; 187 ssize_t (*show)(struct cpufreq_policy *, char *); 188 ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); 189 }; 190 191 #define cpufreq_freq_attr_ro(_name) \ 192 static struct freq_attr _name = \ 193 __ATTR(_name, 0444, show_##_name, NULL) 194 195 #define cpufreq_freq_attr_ro_perm(_name, _perm) \ 196 static struct freq_attr _name = \ 197 __ATTR(_name, _perm, show_##_name, NULL) 198 199 #define cpufreq_freq_attr_rw(_name) \ 200 static struct freq_attr _name = \ 201 __ATTR(_name, 0644, show_##_name, store_##_name) 202 203 struct global_attr { 204 struct attribute attr; 205 ssize_t (*show)(struct kobject *kobj, 206 struct attribute *attr, char *buf); 207 ssize_t (*store)(struct kobject *a, struct attribute *b, 208 const char *c, size_t count); 209 }; 210 211 #define define_one_global_ro(_name) \ 212 static struct global_attr _name = \ 213 __ATTR(_name, 0444, show_##_name, NULL) 214 215 #define define_one_global_rw(_name) \ 216 static struct global_attr _name = \ 217 __ATTR(_name, 0644, show_##_name, store_##_name) 218 219 220 struct cpufreq_driver { 221 char name[CPUFREQ_NAME_LEN]; 222 u8 flags; 223 void *driver_data; 224 225 /* needed by all drivers */ 226 int (*init)(struct cpufreq_policy *policy); 227 int (*verify)(struct cpufreq_policy *policy); 228 229 /* define one out of two */ 230 int (*setpolicy)(struct cpufreq_policy *policy); 231 232 /* 233 * On failure, should always restore frequency to policy->restore_freq 234 * (i.e. old freq). 235 */ 236 int (*target)(struct cpufreq_policy *policy, 237 unsigned int target_freq, 238 unsigned int relation); /* Deprecated */ 239 int (*target_index)(struct cpufreq_policy *policy, 240 unsigned int index); 241 /* 242 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION 243 * unset. 244 * 245 * get_intermediate should return a stable intermediate frequency 246 * platform wants to switch to and target_intermediate() should set CPU 247 * to to that frequency, before jumping to the frequency corresponding 248 * to 'index'. Core will take care of sending notifications and driver 249 * doesn't have to handle them in target_intermediate() or 250 * target_index(). 251 * 252 * Drivers can return '0' from get_intermediate() in case they don't 253 * wish to switch to intermediate frequency for some target frequency. 254 * In that case core will directly call ->target_index(). 255 */ 256 unsigned int (*get_intermediate)(struct cpufreq_policy *policy, 257 unsigned int index); 258 int (*target_intermediate)(struct cpufreq_policy *policy, 259 unsigned int index); 260 261 /* should be defined, if possible */ 262 unsigned int (*get)(unsigned int cpu); 263 264 /* optional */ 265 int (*bios_limit)(int cpu, unsigned int *limit); 266 267 int (*exit)(struct cpufreq_policy *policy); 268 void (*stop_cpu)(struct cpufreq_policy *policy); 269 int (*suspend)(struct cpufreq_policy *policy); 270 int (*resume)(struct cpufreq_policy *policy); 271 272 /* Will be called after the driver is fully initialized */ 273 void (*ready)(struct cpufreq_policy *policy); 274 275 struct freq_attr **attr; 276 277 /* platform specific boost support code */ 278 bool boost_supported; 279 bool boost_enabled; 280 int (*set_boost)(int state); 281 }; 282 283 /* flags */ 284 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if 285 all ->init() calls failed */ 286 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other 287 kernel "constants" aren't 288 affected by frequency 289 transitions */ 290 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume 291 speed mismatches */ 292 293 /* 294 * This should be set by platforms having multiple clock-domains, i.e. 295 * supporting multiple policies. With this sysfs directories of governor would 296 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same 297 * governor with different tunables for different clusters. 298 */ 299 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) 300 301 /* 302 * Driver will do POSTCHANGE notifications from outside of their ->target() 303 * routine and so must set cpufreq_driver->flags with this flag, so that core 304 * can handle them specially. 305 */ 306 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) 307 308 /* 309 * Set by drivers which want cpufreq core to check if CPU is running at a 310 * frequency present in freq-table exposed by the driver. For these drivers if 311 * CPU is found running at an out of table freq, we will try to set it to a freq 312 * from the table. And if that fails, we will stop further boot process by 313 * issuing a BUG_ON(). 314 */ 315 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5) 316 317 int cpufreq_register_driver(struct cpufreq_driver *driver_data); 318 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 319 320 const char *cpufreq_get_current_driver(void); 321 void *cpufreq_get_driver_data(void); 322 323 static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, 324 unsigned int min, unsigned int max) 325 { 326 if (policy->min < min) 327 policy->min = min; 328 if (policy->max < min) 329 policy->max = min; 330 if (policy->min > max) 331 policy->min = max; 332 if (policy->max > max) 333 policy->max = max; 334 if (policy->min > policy->max) 335 policy->min = policy->max; 336 return; 337 } 338 339 static inline void 340 cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) 341 { 342 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, 343 policy->cpuinfo.max_freq); 344 } 345 346 #ifdef CONFIG_CPU_FREQ 347 void cpufreq_suspend(void); 348 void cpufreq_resume(void); 349 int cpufreq_generic_suspend(struct cpufreq_policy *policy); 350 #else 351 static inline void cpufreq_suspend(void) {} 352 static inline void cpufreq_resume(void) {} 353 #endif 354 355 /********************************************************************* 356 * CPUFREQ NOTIFIER INTERFACE * 357 *********************************************************************/ 358 359 #define CPUFREQ_TRANSITION_NOTIFIER (0) 360 #define CPUFREQ_POLICY_NOTIFIER (1) 361 362 /* Transition notifiers */ 363 #define CPUFREQ_PRECHANGE (0) 364 #define CPUFREQ_POSTCHANGE (1) 365 366 /* Policy Notifiers */ 367 #define CPUFREQ_ADJUST (0) 368 #define CPUFREQ_INCOMPATIBLE (1) 369 #define CPUFREQ_NOTIFY (2) 370 #define CPUFREQ_START (3) 371 #define CPUFREQ_CREATE_POLICY (4) 372 #define CPUFREQ_REMOVE_POLICY (5) 373 374 #ifdef CONFIG_CPU_FREQ 375 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); 376 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); 377 378 void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, 379 struct cpufreq_freqs *freqs); 380 void cpufreq_freq_transition_end(struct cpufreq_policy *policy, 381 struct cpufreq_freqs *freqs, int transition_failed); 382 383 #else /* CONFIG_CPU_FREQ */ 384 static inline int cpufreq_register_notifier(struct notifier_block *nb, 385 unsigned int list) 386 { 387 return 0; 388 } 389 static inline int cpufreq_unregister_notifier(struct notifier_block *nb, 390 unsigned int list) 391 { 392 return 0; 393 } 394 #endif /* !CONFIG_CPU_FREQ */ 395 396 /** 397 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch 398 * safe) 399 * @old: old value 400 * @div: divisor 401 * @mult: multiplier 402 * 403 * 404 * new = old * mult / div 405 */ 406 static inline unsigned long cpufreq_scale(unsigned long old, u_int div, 407 u_int mult) 408 { 409 #if BITS_PER_LONG == 32 410 u64 result = ((u64) old) * ((u64) mult); 411 do_div(result, div); 412 return (unsigned long) result; 413 414 #elif BITS_PER_LONG == 64 415 unsigned long result = old * ((u64) mult); 416 result /= div; 417 return result; 418 #endif 419 } 420 421 /********************************************************************* 422 * CPUFREQ GOVERNORS * 423 *********************************************************************/ 424 425 /* 426 * If (cpufreq_driver->target) exists, the ->governor decides what frequency 427 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these 428 * two generic policies are available: 429 */ 430 #define CPUFREQ_POLICY_POWERSAVE (1) 431 #define CPUFREQ_POLICY_PERFORMANCE (2) 432 433 /* Governor Events */ 434 #define CPUFREQ_GOV_START 1 435 #define CPUFREQ_GOV_STOP 2 436 #define CPUFREQ_GOV_LIMITS 3 437 #define CPUFREQ_GOV_POLICY_INIT 4 438 #define CPUFREQ_GOV_POLICY_EXIT 5 439 440 struct cpufreq_governor { 441 char name[CPUFREQ_NAME_LEN]; 442 int initialized; 443 int (*governor) (struct cpufreq_policy *policy, 444 unsigned int event); 445 ssize_t (*show_setspeed) (struct cpufreq_policy *policy, 446 char *buf); 447 int (*store_setspeed) (struct cpufreq_policy *policy, 448 unsigned int freq); 449 unsigned int max_transition_latency; /* HW must be able to switch to 450 next freq faster than this value in nano secs or we 451 will fallback to performance governor */ 452 struct list_head governor_list; 453 struct module *owner; 454 }; 455 456 /* Pass a target to the cpufreq driver */ 457 int cpufreq_driver_target(struct cpufreq_policy *policy, 458 unsigned int target_freq, 459 unsigned int relation); 460 int __cpufreq_driver_target(struct cpufreq_policy *policy, 461 unsigned int target_freq, 462 unsigned int relation); 463 int cpufreq_register_governor(struct cpufreq_governor *governor); 464 void cpufreq_unregister_governor(struct cpufreq_governor *governor); 465 466 /* CPUFREQ DEFAULT GOVERNOR */ 467 /* 468 * Performance governor is fallback governor if any other gov failed to auto 469 * load due latency restrictions 470 */ 471 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE 472 extern struct cpufreq_governor cpufreq_gov_performance; 473 #endif 474 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE 475 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) 476 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) 477 extern struct cpufreq_governor cpufreq_gov_powersave; 478 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) 479 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) 480 extern struct cpufreq_governor cpufreq_gov_userspace; 481 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) 482 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) 483 extern struct cpufreq_governor cpufreq_gov_ondemand; 484 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) 485 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) 486 extern struct cpufreq_governor cpufreq_gov_conservative; 487 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) 488 #endif 489 490 /********************************************************************* 491 * FREQUENCY TABLE HELPERS * 492 *********************************************************************/ 493 494 /* Special Values of .frequency field */ 495 #define CPUFREQ_ENTRY_INVALID ~0u 496 #define CPUFREQ_TABLE_END ~1u 497 /* Special Values of .flags field */ 498 #define CPUFREQ_BOOST_FREQ (1 << 0) 499 500 struct cpufreq_frequency_table { 501 unsigned int flags; 502 unsigned int driver_data; /* driver specific data, not used by core */ 503 unsigned int frequency; /* kHz - doesn't need to be in ascending 504 * order */ 505 }; 506 507 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) 508 int dev_pm_opp_init_cpufreq_table(struct device *dev, 509 struct cpufreq_frequency_table **table); 510 void dev_pm_opp_free_cpufreq_table(struct device *dev, 511 struct cpufreq_frequency_table **table); 512 #else 513 static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, 514 struct cpufreq_frequency_table 515 **table) 516 { 517 return -EINVAL; 518 } 519 520 static inline void dev_pm_opp_free_cpufreq_table(struct device *dev, 521 struct cpufreq_frequency_table 522 **table) 523 { 524 } 525 #endif 526 527 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table **pos) 528 { 529 while ((*pos)->frequency != CPUFREQ_TABLE_END) 530 if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID) 531 return true; 532 else 533 (*pos)++; 534 return false; 535 } 536 537 /* 538 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table 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_entry(pos, table) \ 544 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++) 545 546 /* 547 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table 548 * excluding CPUFREQ_ENTRY_INVALID frequencies. 549 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 550 * @table: the cpufreq_frequency_table * to iterate over. 551 */ 552 553 #define cpufreq_for_each_valid_entry(pos, table) \ 554 for (pos = table; cpufreq_next_valid(&pos); pos++) 555 556 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 557 struct cpufreq_frequency_table *table); 558 559 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 560 struct cpufreq_frequency_table *table); 561 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy); 562 563 int cpufreq_frequency_table_target(struct cpufreq_policy *policy, 564 struct cpufreq_frequency_table *table, 565 unsigned int target_freq, 566 unsigned int relation, 567 unsigned int *index); 568 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, 569 unsigned int freq); 570 571 ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); 572 573 #ifdef CONFIG_CPU_FREQ 574 int cpufreq_boost_trigger_state(int state); 575 int cpufreq_boost_supported(void); 576 int cpufreq_boost_enabled(void); 577 #else 578 static inline int cpufreq_boost_trigger_state(int state) 579 { 580 return 0; 581 } 582 static inline int cpufreq_boost_supported(void) 583 { 584 return 0; 585 } 586 static inline int cpufreq_boost_enabled(void) 587 { 588 return 0; 589 } 590 #endif 591 /* the following funtion is for cpufreq core use only */ 592 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); 593 594 /* the following are really really optional */ 595 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; 596 extern struct freq_attr *cpufreq_generic_attr[]; 597 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy, 598 struct cpufreq_frequency_table *table); 599 600 unsigned int cpufreq_generic_get(unsigned int cpu); 601 int cpufreq_generic_init(struct cpufreq_policy *policy, 602 struct cpufreq_frequency_table *table, 603 unsigned int transition_latency); 604 #endif /* _LINUX_CPUFREQ_H */ 605