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_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 unsigned int kobj_cpu; /* cpu managing sysfs files, can be offline */ 69 70 struct clk *clk; 71 struct cpufreq_cpuinfo cpuinfo;/* see above */ 72 73 unsigned int min; /* in kHz */ 74 unsigned int max; /* in kHz */ 75 unsigned int cur; /* in kHz, only needed if cpufreq 76 * governors are used */ 77 unsigned int restore_freq; /* = policy->cur before transition */ 78 unsigned int suspend_freq; /* freq to set during suspend */ 79 80 unsigned int policy; /* see above */ 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 int cpufreq_get_global_kobject(void); 153 void cpufreq_put_global_kobject(void); 154 int cpufreq_sysfs_create_file(const struct attribute *attr); 155 void cpufreq_sysfs_remove_file(const struct attribute *attr); 156 157 #ifdef CONFIG_CPU_FREQ 158 unsigned int cpufreq_get(unsigned int cpu); 159 unsigned int cpufreq_quick_get(unsigned int cpu); 160 unsigned int cpufreq_quick_get_max(unsigned int cpu); 161 void disable_cpufreq(void); 162 163 u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy); 164 int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); 165 int cpufreq_update_policy(unsigned int cpu); 166 bool have_governor_per_policy(void); 167 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); 168 #else 169 static inline unsigned int cpufreq_get(unsigned int cpu) 170 { 171 return 0; 172 } 173 static inline unsigned int cpufreq_quick_get(unsigned int cpu) 174 { 175 return 0; 176 } 177 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) 178 { 179 return 0; 180 } 181 static inline void disable_cpufreq(void) { } 182 #endif 183 184 /********************************************************************* 185 * CPUFREQ DRIVER INTERFACE * 186 *********************************************************************/ 187 188 #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ 189 #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ 190 #define CPUFREQ_RELATION_C 2 /* closest frequency to target */ 191 192 struct freq_attr { 193 struct attribute attr; 194 ssize_t (*show)(struct cpufreq_policy *, char *); 195 ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); 196 }; 197 198 #define cpufreq_freq_attr_ro(_name) \ 199 static struct freq_attr _name = \ 200 __ATTR(_name, 0444, show_##_name, NULL) 201 202 #define cpufreq_freq_attr_ro_perm(_name, _perm) \ 203 static struct freq_attr _name = \ 204 __ATTR(_name, _perm, show_##_name, NULL) 205 206 #define cpufreq_freq_attr_rw(_name) \ 207 static struct freq_attr _name = \ 208 __ATTR(_name, 0644, show_##_name, store_##_name) 209 210 struct global_attr { 211 struct attribute attr; 212 ssize_t (*show)(struct kobject *kobj, 213 struct attribute *attr, char *buf); 214 ssize_t (*store)(struct kobject *a, struct attribute *b, 215 const char *c, size_t count); 216 }; 217 218 #define define_one_global_ro(_name) \ 219 static struct global_attr _name = \ 220 __ATTR(_name, 0444, show_##_name, NULL) 221 222 #define define_one_global_rw(_name) \ 223 static struct global_attr _name = \ 224 __ATTR(_name, 0644, show_##_name, store_##_name) 225 226 227 struct cpufreq_driver { 228 char name[CPUFREQ_NAME_LEN]; 229 u8 flags; 230 void *driver_data; 231 232 /* needed by all drivers */ 233 int (*init)(struct cpufreq_policy *policy); 234 int (*verify)(struct cpufreq_policy *policy); 235 236 /* define one out of two */ 237 int (*setpolicy)(struct cpufreq_policy *policy); 238 239 /* 240 * On failure, should always restore frequency to policy->restore_freq 241 * (i.e. old freq). 242 */ 243 int (*target)(struct cpufreq_policy *policy, 244 unsigned int target_freq, 245 unsigned int relation); /* Deprecated */ 246 int (*target_index)(struct cpufreq_policy *policy, 247 unsigned int index); 248 /* 249 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION 250 * unset. 251 * 252 * get_intermediate should return a stable intermediate frequency 253 * platform wants to switch to and target_intermediate() should set CPU 254 * to to that frequency, before jumping to the frequency corresponding 255 * to 'index'. Core will take care of sending notifications and driver 256 * doesn't have to handle them in target_intermediate() or 257 * target_index(). 258 * 259 * Drivers can return '0' from get_intermediate() in case they don't 260 * wish to switch to intermediate frequency for some target frequency. 261 * In that case core will directly call ->target_index(). 262 */ 263 unsigned int (*get_intermediate)(struct cpufreq_policy *policy, 264 unsigned int index); 265 int (*target_intermediate)(struct cpufreq_policy *policy, 266 unsigned int index); 267 268 /* should be defined, if possible */ 269 unsigned int (*get)(unsigned int cpu); 270 271 /* optional */ 272 int (*bios_limit)(int cpu, unsigned int *limit); 273 274 int (*exit)(struct cpufreq_policy *policy); 275 void (*stop_cpu)(struct cpufreq_policy *policy); 276 int (*suspend)(struct cpufreq_policy *policy); 277 int (*resume)(struct cpufreq_policy *policy); 278 279 /* Will be called after the driver is fully initialized */ 280 void (*ready)(struct cpufreq_policy *policy); 281 282 struct freq_attr **attr; 283 284 /* platform specific boost support code */ 285 bool boost_supported; 286 bool boost_enabled; 287 int (*set_boost)(int state); 288 }; 289 290 /* flags */ 291 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if 292 all ->init() calls failed */ 293 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other 294 kernel "constants" aren't 295 affected by frequency 296 transitions */ 297 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume 298 speed mismatches */ 299 300 /* 301 * This should be set by platforms having multiple clock-domains, i.e. 302 * supporting multiple policies. With this sysfs directories of governor would 303 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same 304 * governor with different tunables for different clusters. 305 */ 306 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) 307 308 /* 309 * Driver will do POSTCHANGE notifications from outside of their ->target() 310 * routine and so must set cpufreq_driver->flags with this flag, so that core 311 * can handle them specially. 312 */ 313 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) 314 315 /* 316 * Set by drivers which want cpufreq core to check if CPU is running at a 317 * frequency present in freq-table exposed by the driver. For these drivers if 318 * CPU is found running at an out of table freq, we will try to set it to a freq 319 * from the table. And if that fails, we will stop further boot process by 320 * issuing a BUG_ON(). 321 */ 322 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5) 323 324 int cpufreq_register_driver(struct cpufreq_driver *driver_data); 325 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 326 327 const char *cpufreq_get_current_driver(void); 328 void *cpufreq_get_driver_data(void); 329 330 static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, 331 unsigned int min, unsigned int max) 332 { 333 if (policy->min < min) 334 policy->min = min; 335 if (policy->max < min) 336 policy->max = min; 337 if (policy->min > max) 338 policy->min = max; 339 if (policy->max > max) 340 policy->max = max; 341 if (policy->min > policy->max) 342 policy->min = policy->max; 343 return; 344 } 345 346 static inline void 347 cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) 348 { 349 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, 350 policy->cpuinfo.max_freq); 351 } 352 353 #ifdef CONFIG_CPU_FREQ 354 void cpufreq_suspend(void); 355 void cpufreq_resume(void); 356 int cpufreq_generic_suspend(struct cpufreq_policy *policy); 357 #else 358 static inline void cpufreq_suspend(void) {} 359 static inline void cpufreq_resume(void) {} 360 #endif 361 362 /********************************************************************* 363 * CPUFREQ NOTIFIER INTERFACE * 364 *********************************************************************/ 365 366 #define CPUFREQ_TRANSITION_NOTIFIER (0) 367 #define CPUFREQ_POLICY_NOTIFIER (1) 368 369 /* Transition notifiers */ 370 #define CPUFREQ_PRECHANGE (0) 371 #define CPUFREQ_POSTCHANGE (1) 372 373 /* Policy Notifiers */ 374 #define CPUFREQ_ADJUST (0) 375 #define CPUFREQ_NOTIFY (1) 376 #define CPUFREQ_START (2) 377 #define CPUFREQ_CREATE_POLICY (3) 378 #define CPUFREQ_REMOVE_POLICY (4) 379 380 #ifdef CONFIG_CPU_FREQ 381 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); 382 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); 383 384 void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, 385 struct cpufreq_freqs *freqs); 386 void cpufreq_freq_transition_end(struct cpufreq_policy *policy, 387 struct cpufreq_freqs *freqs, int transition_failed); 388 389 #else /* CONFIG_CPU_FREQ */ 390 static inline int cpufreq_register_notifier(struct notifier_block *nb, 391 unsigned int list) 392 { 393 return 0; 394 } 395 static inline int cpufreq_unregister_notifier(struct notifier_block *nb, 396 unsigned int list) 397 { 398 return 0; 399 } 400 #endif /* !CONFIG_CPU_FREQ */ 401 402 /** 403 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch 404 * safe) 405 * @old: old value 406 * @div: divisor 407 * @mult: multiplier 408 * 409 * 410 * new = old * mult / div 411 */ 412 static inline unsigned long cpufreq_scale(unsigned long old, u_int div, 413 u_int mult) 414 { 415 #if BITS_PER_LONG == 32 416 u64 result = ((u64) old) * ((u64) mult); 417 do_div(result, div); 418 return (unsigned long) result; 419 420 #elif BITS_PER_LONG == 64 421 unsigned long result = old * ((u64) mult); 422 result /= div; 423 return result; 424 #endif 425 } 426 427 /********************************************************************* 428 * CPUFREQ GOVERNORS * 429 *********************************************************************/ 430 431 /* 432 * If (cpufreq_driver->target) exists, the ->governor decides what frequency 433 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these 434 * two generic policies are available: 435 */ 436 #define CPUFREQ_POLICY_POWERSAVE (1) 437 #define CPUFREQ_POLICY_PERFORMANCE (2) 438 439 /* Governor Events */ 440 #define CPUFREQ_GOV_START 1 441 #define CPUFREQ_GOV_STOP 2 442 #define CPUFREQ_GOV_LIMITS 3 443 #define CPUFREQ_GOV_POLICY_INIT 4 444 #define CPUFREQ_GOV_POLICY_EXIT 5 445 446 struct cpufreq_governor { 447 char name[CPUFREQ_NAME_LEN]; 448 int initialized; 449 int (*governor) (struct cpufreq_policy *policy, 450 unsigned int event); 451 ssize_t (*show_setspeed) (struct cpufreq_policy *policy, 452 char *buf); 453 int (*store_setspeed) (struct cpufreq_policy *policy, 454 unsigned int freq); 455 unsigned int max_transition_latency; /* HW must be able to switch to 456 next freq faster than this value in nano secs or we 457 will fallback to performance governor */ 458 struct list_head governor_list; 459 struct module *owner; 460 }; 461 462 /* Pass a target to the cpufreq driver */ 463 int cpufreq_driver_target(struct cpufreq_policy *policy, 464 unsigned int target_freq, 465 unsigned int relation); 466 int __cpufreq_driver_target(struct cpufreq_policy *policy, 467 unsigned int target_freq, 468 unsigned int relation); 469 int cpufreq_register_governor(struct cpufreq_governor *governor); 470 void cpufreq_unregister_governor(struct cpufreq_governor *governor); 471 472 /* CPUFREQ DEFAULT GOVERNOR */ 473 /* 474 * Performance governor is fallback governor if any other gov failed to auto 475 * load due latency restrictions 476 */ 477 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE 478 extern struct cpufreq_governor cpufreq_gov_performance; 479 #endif 480 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE 481 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) 482 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) 483 extern struct cpufreq_governor cpufreq_gov_powersave; 484 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) 485 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) 486 extern struct cpufreq_governor cpufreq_gov_userspace; 487 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) 488 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) 489 extern struct cpufreq_governor cpufreq_gov_ondemand; 490 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) 491 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) 492 extern struct cpufreq_governor cpufreq_gov_conservative; 493 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) 494 #endif 495 496 /********************************************************************* 497 * FREQUENCY TABLE HELPERS * 498 *********************************************************************/ 499 500 /* Special Values of .frequency field */ 501 #define CPUFREQ_ENTRY_INVALID ~0u 502 #define CPUFREQ_TABLE_END ~1u 503 /* Special Values of .flags field */ 504 #define CPUFREQ_BOOST_FREQ (1 << 0) 505 506 struct cpufreq_frequency_table { 507 unsigned int flags; 508 unsigned int driver_data; /* driver specific data, not used by core */ 509 unsigned int frequency; /* kHz - doesn't need to be in ascending 510 * order */ 511 }; 512 513 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) 514 int dev_pm_opp_init_cpufreq_table(struct device *dev, 515 struct cpufreq_frequency_table **table); 516 void dev_pm_opp_free_cpufreq_table(struct device *dev, 517 struct cpufreq_frequency_table **table); 518 #else 519 static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, 520 struct cpufreq_frequency_table 521 **table) 522 { 523 return -EINVAL; 524 } 525 526 static inline void dev_pm_opp_free_cpufreq_table(struct device *dev, 527 struct cpufreq_frequency_table 528 **table) 529 { 530 } 531 #endif 532 533 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table **pos) 534 { 535 while ((*pos)->frequency != CPUFREQ_TABLE_END) 536 if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID) 537 return true; 538 else 539 (*pos)++; 540 return false; 541 } 542 543 /* 544 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table 545 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 546 * @table: the cpufreq_frequency_table * to iterate over. 547 */ 548 549 #define cpufreq_for_each_entry(pos, table) \ 550 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++) 551 552 /* 553 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table 554 * excluding CPUFREQ_ENTRY_INVALID frequencies. 555 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 556 * @table: the cpufreq_frequency_table * to iterate over. 557 */ 558 559 #define cpufreq_for_each_valid_entry(pos, table) \ 560 for (pos = table; cpufreq_next_valid(&pos); pos++) 561 562 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 563 struct cpufreq_frequency_table *table); 564 565 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 566 struct cpufreq_frequency_table *table); 567 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy); 568 569 int cpufreq_frequency_table_target(struct cpufreq_policy *policy, 570 struct cpufreq_frequency_table *table, 571 unsigned int target_freq, 572 unsigned int relation, 573 unsigned int *index); 574 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, 575 unsigned int freq); 576 577 ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); 578 579 #ifdef CONFIG_CPU_FREQ 580 int cpufreq_boost_trigger_state(int state); 581 int cpufreq_boost_supported(void); 582 int cpufreq_boost_enabled(void); 583 int cpufreq_enable_boost_support(void); 584 bool policy_has_boost_freq(struct cpufreq_policy *policy); 585 #else 586 static inline int cpufreq_boost_trigger_state(int state) 587 { 588 return 0; 589 } 590 static inline int cpufreq_boost_supported(void) 591 { 592 return 0; 593 } 594 static inline int cpufreq_boost_enabled(void) 595 { 596 return 0; 597 } 598 599 static inline int cpufreq_enable_boost_support(void) 600 { 601 return -EINVAL; 602 } 603 604 static inline bool policy_has_boost_freq(struct cpufreq_policy *policy) 605 { 606 return false; 607 } 608 #endif 609 /* the following funtion is for cpufreq core use only */ 610 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); 611 612 /* the following are really really optional */ 613 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; 614 extern struct freq_attr cpufreq_freq_attr_scaling_boost_freqs; 615 extern struct freq_attr *cpufreq_generic_attr[]; 616 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy, 617 struct cpufreq_frequency_table *table); 618 619 unsigned int cpufreq_generic_get(unsigned int cpu); 620 int cpufreq_generic_init(struct cpufreq_policy *policy, 621 struct cpufreq_frequency_table *table, 622 unsigned int transition_latency); 623 #endif /* _LINUX_CPUFREQ_H */ 624