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 managing this policy, must be online */ 69 unsigned int kobj_cpu; /* cpu managing sysfs files, can be offline */ 70 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 char last_governor[CPUFREQ_NAME_LEN]; /* last governor used */ 86 87 struct work_struct update; /* if update_policy() needs to be 88 * called, but you're in IRQ context */ 89 90 struct cpufreq_real_policy user_policy; 91 struct cpufreq_frequency_table *freq_table; 92 93 struct list_head policy_list; 94 struct kobject kobj; 95 struct completion kobj_unregister; 96 97 /* 98 * The rules for this semaphore: 99 * - Any routine that wants to read from the policy structure will 100 * do a down_read on this semaphore. 101 * - Any routine that will write to the policy structure and/or may take away 102 * the policy altogether (eg. CPU hotplug), will hold this lock in write 103 * mode before doing so. 104 * 105 * Additional rules: 106 * - Lock should not be held across 107 * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); 108 */ 109 struct rw_semaphore rwsem; 110 111 /* Synchronization for frequency transitions */ 112 bool transition_ongoing; /* Tracks transition status */ 113 spinlock_t transition_lock; 114 wait_queue_head_t transition_wait; 115 struct task_struct *transition_task; /* Task which is doing the transition */ 116 117 /* cpufreq-stats */ 118 struct cpufreq_stats *stats; 119 120 /* For cpufreq driver's internal use */ 121 void *driver_data; 122 }; 123 124 /* Only for ACPI */ 125 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ 126 #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ 127 #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ 128 #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ 129 130 #ifdef CONFIG_CPU_FREQ 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(unsigned int cpu) 135 { 136 return NULL; 137 } 138 static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { } 139 #endif 140 141 static inline bool policy_is_shared(struct cpufreq_policy *policy) 142 { 143 return cpumask_weight(policy->cpus) > 1; 144 } 145 146 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */ 147 extern struct kobject *cpufreq_global_kobject; 148 int cpufreq_get_global_kobject(void); 149 void cpufreq_put_global_kobject(void); 150 int cpufreq_sysfs_create_file(const struct attribute *attr); 151 void cpufreq_sysfs_remove_file(const struct attribute *attr); 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_supported; 282 bool boost_enabled; 283 int (*set_boost)(int state); 284 }; 285 286 /* flags */ 287 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if 288 all ->init() calls failed */ 289 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other 290 kernel "constants" aren't 291 affected by frequency 292 transitions */ 293 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume 294 speed mismatches */ 295 296 /* 297 * This should be set by platforms having multiple clock-domains, i.e. 298 * supporting multiple policies. With this sysfs directories of governor would 299 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same 300 * governor with different tunables for different clusters. 301 */ 302 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) 303 304 /* 305 * Driver will do POSTCHANGE notifications from outside of their ->target() 306 * routine and so must set cpufreq_driver->flags with this flag, so that core 307 * can handle them specially. 308 */ 309 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) 310 311 /* 312 * Set by drivers which want cpufreq core to check if CPU is running at a 313 * frequency present in freq-table exposed by the driver. For these drivers if 314 * CPU is found running at an out of table freq, we will try to set it to a freq 315 * from the table. And if that fails, we will stop further boot process by 316 * issuing a BUG_ON(). 317 */ 318 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5) 319 320 int cpufreq_register_driver(struct cpufreq_driver *driver_data); 321 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 322 323 const char *cpufreq_get_current_driver(void); 324 void *cpufreq_get_driver_data(void); 325 326 static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, 327 unsigned int min, unsigned int max) 328 { 329 if (policy->min < min) 330 policy->min = min; 331 if (policy->max < min) 332 policy->max = min; 333 if (policy->min > max) 334 policy->min = max; 335 if (policy->max > max) 336 policy->max = max; 337 if (policy->min > policy->max) 338 policy->min = policy->max; 339 return; 340 } 341 342 static inline void 343 cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) 344 { 345 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, 346 policy->cpuinfo.max_freq); 347 } 348 349 #ifdef CONFIG_CPU_FREQ 350 void cpufreq_suspend(void); 351 void cpufreq_resume(void); 352 int cpufreq_generic_suspend(struct cpufreq_policy *policy); 353 #else 354 static inline void cpufreq_suspend(void) {} 355 static inline void cpufreq_resume(void) {} 356 #endif 357 358 /********************************************************************* 359 * CPUFREQ NOTIFIER INTERFACE * 360 *********************************************************************/ 361 362 #define CPUFREQ_TRANSITION_NOTIFIER (0) 363 #define CPUFREQ_POLICY_NOTIFIER (1) 364 365 /* Transition notifiers */ 366 #define CPUFREQ_PRECHANGE (0) 367 #define CPUFREQ_POSTCHANGE (1) 368 369 /* Policy Notifiers */ 370 #define CPUFREQ_ADJUST (0) 371 #define CPUFREQ_INCOMPATIBLE (1) 372 #define CPUFREQ_NOTIFY (2) 373 #define CPUFREQ_START (3) 374 #define CPUFREQ_CREATE_POLICY (4) 375 #define CPUFREQ_REMOVE_POLICY (5) 376 377 #ifdef CONFIG_CPU_FREQ 378 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); 379 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); 380 381 void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, 382 struct cpufreq_freqs *freqs); 383 void cpufreq_freq_transition_end(struct cpufreq_policy *policy, 384 struct cpufreq_freqs *freqs, int transition_failed); 385 386 #else /* CONFIG_CPU_FREQ */ 387 static inline int cpufreq_register_notifier(struct notifier_block *nb, 388 unsigned int list) 389 { 390 return 0; 391 } 392 static inline int cpufreq_unregister_notifier(struct notifier_block *nb, 393 unsigned int list) 394 { 395 return 0; 396 } 397 #endif /* !CONFIG_CPU_FREQ */ 398 399 /** 400 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch 401 * safe) 402 * @old: old value 403 * @div: divisor 404 * @mult: multiplier 405 * 406 * 407 * new = old * mult / div 408 */ 409 static inline unsigned long cpufreq_scale(unsigned long old, u_int div, 410 u_int mult) 411 { 412 #if BITS_PER_LONG == 32 413 u64 result = ((u64) old) * ((u64) mult); 414 do_div(result, div); 415 return (unsigned long) result; 416 417 #elif BITS_PER_LONG == 64 418 unsigned long result = old * ((u64) mult); 419 result /= div; 420 return result; 421 #endif 422 } 423 424 /********************************************************************* 425 * CPUFREQ GOVERNORS * 426 *********************************************************************/ 427 428 /* 429 * If (cpufreq_driver->target) exists, the ->governor decides what frequency 430 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these 431 * two generic policies are available: 432 */ 433 #define CPUFREQ_POLICY_POWERSAVE (1) 434 #define CPUFREQ_POLICY_PERFORMANCE (2) 435 436 /* Governor Events */ 437 #define CPUFREQ_GOV_START 1 438 #define CPUFREQ_GOV_STOP 2 439 #define CPUFREQ_GOV_LIMITS 3 440 #define CPUFREQ_GOV_POLICY_INIT 4 441 #define CPUFREQ_GOV_POLICY_EXIT 5 442 443 struct cpufreq_governor { 444 char name[CPUFREQ_NAME_LEN]; 445 int initialized; 446 int (*governor) (struct cpufreq_policy *policy, 447 unsigned int event); 448 ssize_t (*show_setspeed) (struct cpufreq_policy *policy, 449 char *buf); 450 int (*store_setspeed) (struct cpufreq_policy *policy, 451 unsigned int freq); 452 unsigned int max_transition_latency; /* HW must be able to switch to 453 next freq faster than this value in nano secs or we 454 will fallback to performance governor */ 455 struct list_head governor_list; 456 struct module *owner; 457 }; 458 459 /* Pass a target to the cpufreq driver */ 460 int cpufreq_driver_target(struct cpufreq_policy *policy, 461 unsigned int target_freq, 462 unsigned int relation); 463 int __cpufreq_driver_target(struct cpufreq_policy *policy, 464 unsigned int target_freq, 465 unsigned int relation); 466 int cpufreq_register_governor(struct cpufreq_governor *governor); 467 void cpufreq_unregister_governor(struct cpufreq_governor *governor); 468 469 /* CPUFREQ DEFAULT GOVERNOR */ 470 /* 471 * Performance governor is fallback governor if any other gov failed to auto 472 * load due latency restrictions 473 */ 474 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE 475 extern struct cpufreq_governor cpufreq_gov_performance; 476 #endif 477 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE 478 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) 479 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) 480 extern struct cpufreq_governor cpufreq_gov_powersave; 481 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) 482 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) 483 extern struct cpufreq_governor cpufreq_gov_userspace; 484 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) 485 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) 486 extern struct cpufreq_governor cpufreq_gov_ondemand; 487 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) 488 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) 489 extern struct cpufreq_governor cpufreq_gov_conservative; 490 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) 491 #endif 492 493 /********************************************************************* 494 * FREQUENCY TABLE HELPERS * 495 *********************************************************************/ 496 497 /* Special Values of .frequency field */ 498 #define CPUFREQ_ENTRY_INVALID ~0u 499 #define CPUFREQ_TABLE_END ~1u 500 /* Special Values of .flags field */ 501 #define CPUFREQ_BOOST_FREQ (1 << 0) 502 503 struct cpufreq_frequency_table { 504 unsigned int flags; 505 unsigned int driver_data; /* driver specific data, not used by core */ 506 unsigned int frequency; /* kHz - doesn't need to be in ascending 507 * order */ 508 }; 509 510 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) 511 int dev_pm_opp_init_cpufreq_table(struct device *dev, 512 struct cpufreq_frequency_table **table); 513 void dev_pm_opp_free_cpufreq_table(struct device *dev, 514 struct cpufreq_frequency_table **table); 515 #else 516 static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, 517 struct cpufreq_frequency_table 518 **table) 519 { 520 return -EINVAL; 521 } 522 523 static inline void dev_pm_opp_free_cpufreq_table(struct device *dev, 524 struct cpufreq_frequency_table 525 **table) 526 { 527 } 528 #endif 529 530 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table **pos) 531 { 532 while ((*pos)->frequency != CPUFREQ_TABLE_END) 533 if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID) 534 return true; 535 else 536 (*pos)++; 537 return false; 538 } 539 540 /* 541 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table 542 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 543 * @table: the cpufreq_frequency_table * to iterate over. 544 */ 545 546 #define cpufreq_for_each_entry(pos, table) \ 547 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++) 548 549 /* 550 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table 551 * excluding CPUFREQ_ENTRY_INVALID frequencies. 552 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 553 * @table: the cpufreq_frequency_table * to iterate over. 554 */ 555 556 #define cpufreq_for_each_valid_entry(pos, table) \ 557 for (pos = table; cpufreq_next_valid(&pos); pos++) 558 559 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 560 struct cpufreq_frequency_table *table); 561 562 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 563 struct cpufreq_frequency_table *table); 564 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy); 565 566 int cpufreq_frequency_table_target(struct cpufreq_policy *policy, 567 struct cpufreq_frequency_table *table, 568 unsigned int target_freq, 569 unsigned int relation, 570 unsigned int *index); 571 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, 572 unsigned int freq); 573 574 ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); 575 576 #ifdef CONFIG_CPU_FREQ 577 int cpufreq_boost_trigger_state(int state); 578 int cpufreq_boost_supported(void); 579 int cpufreq_boost_enabled(void); 580 #else 581 static inline int cpufreq_boost_trigger_state(int state) 582 { 583 return 0; 584 } 585 static inline int cpufreq_boost_supported(void) 586 { 587 return 0; 588 } 589 static inline int cpufreq_boost_enabled(void) 590 { 591 return 0; 592 } 593 #endif 594 /* the following funtion is for cpufreq core use only */ 595 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); 596 597 /* the following are really really optional */ 598 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; 599 extern struct freq_attr *cpufreq_generic_attr[]; 600 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy, 601 struct cpufreq_frequency_table *table); 602 603 unsigned int cpufreq_generic_get(unsigned int cpu); 604 int cpufreq_generic_init(struct cpufreq_policy *policy, 605 struct cpufreq_frequency_table *table, 606 unsigned int transition_latency); 607 #endif /* _LINUX_CPUFREQ_H */ 608