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 void *driver_data; 223 224 /* needed by all drivers */ 225 int (*init)(struct cpufreq_policy *policy); 226 int (*verify)(struct cpufreq_policy *policy); 227 228 /* define one out of two */ 229 int (*setpolicy)(struct cpufreq_policy *policy); 230 231 /* 232 * On failure, should always restore frequency to policy->restore_freq 233 * (i.e. old freq). 234 */ 235 int (*target)(struct cpufreq_policy *policy, 236 unsigned int target_freq, 237 unsigned int relation); /* Deprecated */ 238 int (*target_index)(struct cpufreq_policy *policy, 239 unsigned int index); 240 /* 241 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION 242 * unset. 243 * 244 * get_intermediate should return a stable intermediate frequency 245 * platform wants to switch to and target_intermediate() should set CPU 246 * to to that frequency, before jumping to the frequency corresponding 247 * to 'index'. Core will take care of sending notifications and driver 248 * doesn't have to handle them in target_intermediate() or 249 * target_index(). 250 * 251 * Drivers can return '0' from get_intermediate() in case they don't 252 * wish to switch to intermediate frequency for some target frequency. 253 * In that case core will directly call ->target_index(). 254 */ 255 unsigned int (*get_intermediate)(struct cpufreq_policy *policy, 256 unsigned int index); 257 int (*target_intermediate)(struct cpufreq_policy *policy, 258 unsigned int index); 259 260 /* should be defined, if possible */ 261 unsigned int (*get)(unsigned int cpu); 262 263 /* optional */ 264 int (*bios_limit)(int cpu, unsigned int *limit); 265 266 int (*exit)(struct cpufreq_policy *policy); 267 void (*stop_cpu)(struct cpufreq_policy *policy); 268 int (*suspend)(struct cpufreq_policy *policy); 269 int (*resume)(struct cpufreq_policy *policy); 270 271 /* Will be called after the driver is fully initialized */ 272 void (*ready)(struct cpufreq_policy *policy); 273 274 struct freq_attr **attr; 275 276 /* platform specific boost support code */ 277 bool boost_supported; 278 bool boost_enabled; 279 int (*set_boost)(int state); 280 }; 281 282 /* flags */ 283 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if 284 all ->init() calls failed */ 285 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other 286 kernel "constants" aren't 287 affected by frequency 288 transitions */ 289 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume 290 speed mismatches */ 291 292 /* 293 * This should be set by platforms having multiple clock-domains, i.e. 294 * supporting multiple policies. With this sysfs directories of governor would 295 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same 296 * governor with different tunables for different clusters. 297 */ 298 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) 299 300 /* 301 * Driver will do POSTCHANGE notifications from outside of their ->target() 302 * routine and so must set cpufreq_driver->flags with this flag, so that core 303 * can handle them specially. 304 */ 305 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) 306 307 /* 308 * Set by drivers which want cpufreq core to check if CPU is running at a 309 * frequency present in freq-table exposed by the driver. For these drivers if 310 * CPU is found running at an out of table freq, we will try to set it to a freq 311 * from the table. And if that fails, we will stop further boot process by 312 * issuing a BUG_ON(). 313 */ 314 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5) 315 316 int cpufreq_register_driver(struct cpufreq_driver *driver_data); 317 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 318 319 const char *cpufreq_get_current_driver(void); 320 void *cpufreq_get_driver_data(void); 321 322 static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, 323 unsigned int min, unsigned int max) 324 { 325 if (policy->min < min) 326 policy->min = min; 327 if (policy->max < min) 328 policy->max = min; 329 if (policy->min > max) 330 policy->min = max; 331 if (policy->max > max) 332 policy->max = max; 333 if (policy->min > policy->max) 334 policy->min = policy->max; 335 return; 336 } 337 338 static inline void 339 cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) 340 { 341 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, 342 policy->cpuinfo.max_freq); 343 } 344 345 #ifdef CONFIG_CPU_FREQ 346 void cpufreq_suspend(void); 347 void cpufreq_resume(void); 348 int cpufreq_generic_suspend(struct cpufreq_policy *policy); 349 #else 350 static inline void cpufreq_suspend(void) {} 351 static inline void cpufreq_resume(void) {} 352 #endif 353 354 /********************************************************************* 355 * CPUFREQ NOTIFIER INTERFACE * 356 *********************************************************************/ 357 358 #define CPUFREQ_TRANSITION_NOTIFIER (0) 359 #define CPUFREQ_POLICY_NOTIFIER (1) 360 361 /* Transition notifiers */ 362 #define CPUFREQ_PRECHANGE (0) 363 #define CPUFREQ_POSTCHANGE (1) 364 365 /* Policy Notifiers */ 366 #define CPUFREQ_ADJUST (0) 367 #define CPUFREQ_INCOMPATIBLE (1) 368 #define CPUFREQ_NOTIFY (2) 369 #define CPUFREQ_START (3) 370 #define CPUFREQ_UPDATE_POLICY_CPU (4) 371 #define CPUFREQ_CREATE_POLICY (5) 372 #define CPUFREQ_REMOVE_POLICY (6) 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