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 cpumask_var_t real_cpus; /* Related and present */ 66 67 unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs 68 should set cpufreq */ 69 unsigned int cpu; /* cpu managing this policy, must be online */ 70 unsigned int kobj_cpu; /* cpu managing sysfs files, can be offline */ 71 72 struct clk *clk; 73 struct cpufreq_cpuinfo cpuinfo;/* see above */ 74 75 unsigned int min; /* in kHz */ 76 unsigned int max; /* in kHz */ 77 unsigned int cur; /* in kHz, only needed if cpufreq 78 * governors are used */ 79 unsigned int restore_freq; /* = policy->cur before transition */ 80 unsigned int suspend_freq; /* freq to set during suspend */ 81 82 unsigned int policy; /* see above */ 83 struct cpufreq_governor *governor; /* see below */ 84 void *governor_data; 85 bool governor_enabled; /* governor start/stop flag */ 86 char last_governor[CPUFREQ_NAME_LEN]; /* last governor used */ 87 88 struct work_struct update; /* if update_policy() needs to be 89 * called, but you're in IRQ context */ 90 91 struct cpufreq_real_policy user_policy; 92 struct cpufreq_frequency_table *freq_table; 93 94 struct list_head policy_list; 95 struct kobject kobj; 96 struct completion kobj_unregister; 97 98 /* 99 * The rules for this semaphore: 100 * - Any routine that wants to read from the policy structure will 101 * do a down_read on this semaphore. 102 * - Any routine that will write to the policy structure and/or may take away 103 * the policy altogether (eg. CPU hotplug), will hold this lock in write 104 * mode before doing so. 105 * 106 * Additional rules: 107 * - Lock should not be held across 108 * __cpufreq_governor(data, CPUFREQ_GOV_POLICY_EXIT); 109 */ 110 struct rw_semaphore rwsem; 111 112 /* Synchronization for frequency transitions */ 113 bool transition_ongoing; /* Tracks transition status */ 114 spinlock_t transition_lock; 115 wait_queue_head_t transition_wait; 116 struct task_struct *transition_task; /* Task which is doing the transition */ 117 118 /* cpufreq-stats */ 119 struct cpufreq_stats *stats; 120 121 /* For cpufreq driver's internal use */ 122 void *driver_data; 123 }; 124 125 /* Only for ACPI */ 126 #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ 127 #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ 128 #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ 129 #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ 130 131 #ifdef CONFIG_CPU_FREQ 132 struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); 133 void cpufreq_cpu_put(struct cpufreq_policy *policy); 134 #else 135 static inline struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) 136 { 137 return NULL; 138 } 139 static inline void cpufreq_cpu_put(struct cpufreq_policy *policy) { } 140 #endif 141 142 static inline bool policy_is_shared(struct cpufreq_policy *policy) 143 { 144 return cpumask_weight(policy->cpus) > 1; 145 } 146 147 /* /sys/devices/system/cpu/cpufreq: entry point for global variables */ 148 extern struct kobject *cpufreq_global_kobject; 149 int cpufreq_get_global_kobject(void); 150 void cpufreq_put_global_kobject(void); 151 int cpufreq_sysfs_create_file(const struct attribute *attr); 152 void cpufreq_sysfs_remove_file(const struct attribute *attr); 153 154 #ifdef CONFIG_CPU_FREQ 155 unsigned int cpufreq_get(unsigned int cpu); 156 unsigned int cpufreq_quick_get(unsigned int cpu); 157 unsigned int cpufreq_quick_get_max(unsigned int cpu); 158 void disable_cpufreq(void); 159 160 u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy); 161 int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); 162 int cpufreq_update_policy(unsigned int cpu); 163 bool have_governor_per_policy(void); 164 struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy); 165 #else 166 static inline unsigned int cpufreq_get(unsigned int cpu) 167 { 168 return 0; 169 } 170 static inline unsigned int cpufreq_quick_get(unsigned int cpu) 171 { 172 return 0; 173 } 174 static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) 175 { 176 return 0; 177 } 178 static inline void disable_cpufreq(void) { } 179 #endif 180 181 /********************************************************************* 182 * CPUFREQ DRIVER INTERFACE * 183 *********************************************************************/ 184 185 #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ 186 #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ 187 #define CPUFREQ_RELATION_C 2 /* closest frequency to target */ 188 189 struct freq_attr { 190 struct attribute attr; 191 ssize_t (*show)(struct cpufreq_policy *, char *); 192 ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); 193 }; 194 195 #define cpufreq_freq_attr_ro(_name) \ 196 static struct freq_attr _name = \ 197 __ATTR(_name, 0444, show_##_name, NULL) 198 199 #define cpufreq_freq_attr_ro_perm(_name, _perm) \ 200 static struct freq_attr _name = \ 201 __ATTR(_name, _perm, show_##_name, NULL) 202 203 #define cpufreq_freq_attr_rw(_name) \ 204 static struct freq_attr _name = \ 205 __ATTR(_name, 0644, show_##_name, store_##_name) 206 207 struct global_attr { 208 struct attribute attr; 209 ssize_t (*show)(struct kobject *kobj, 210 struct attribute *attr, char *buf); 211 ssize_t (*store)(struct kobject *a, struct attribute *b, 212 const char *c, size_t count); 213 }; 214 215 #define define_one_global_ro(_name) \ 216 static struct global_attr _name = \ 217 __ATTR(_name, 0444, show_##_name, NULL) 218 219 #define define_one_global_rw(_name) \ 220 static struct global_attr _name = \ 221 __ATTR(_name, 0644, show_##_name, store_##_name) 222 223 224 struct cpufreq_driver { 225 char name[CPUFREQ_NAME_LEN]; 226 u8 flags; 227 void *driver_data; 228 229 /* needed by all drivers */ 230 int (*init)(struct cpufreq_policy *policy); 231 int (*verify)(struct cpufreq_policy *policy); 232 233 /* define one out of two */ 234 int (*setpolicy)(struct cpufreq_policy *policy); 235 236 /* 237 * On failure, should always restore frequency to policy->restore_freq 238 * (i.e. old freq). 239 */ 240 int (*target)(struct cpufreq_policy *policy, 241 unsigned int target_freq, 242 unsigned int relation); /* Deprecated */ 243 int (*target_index)(struct cpufreq_policy *policy, 244 unsigned int index); 245 /* 246 * Only for drivers with target_index() and CPUFREQ_ASYNC_NOTIFICATION 247 * unset. 248 * 249 * get_intermediate should return a stable intermediate frequency 250 * platform wants to switch to and target_intermediate() should set CPU 251 * to to that frequency, before jumping to the frequency corresponding 252 * to 'index'. Core will take care of sending notifications and driver 253 * doesn't have to handle them in target_intermediate() or 254 * target_index(). 255 * 256 * Drivers can return '0' from get_intermediate() in case they don't 257 * wish to switch to intermediate frequency for some target frequency. 258 * In that case core will directly call ->target_index(). 259 */ 260 unsigned int (*get_intermediate)(struct cpufreq_policy *policy, 261 unsigned int index); 262 int (*target_intermediate)(struct cpufreq_policy *policy, 263 unsigned int index); 264 265 /* should be defined, if possible */ 266 unsigned int (*get)(unsigned int cpu); 267 268 /* optional */ 269 int (*bios_limit)(int cpu, unsigned int *limit); 270 271 int (*exit)(struct cpufreq_policy *policy); 272 void (*stop_cpu)(struct cpufreq_policy *policy); 273 int (*suspend)(struct cpufreq_policy *policy); 274 int (*resume)(struct cpufreq_policy *policy); 275 276 /* Will be called after the driver is fully initialized */ 277 void (*ready)(struct cpufreq_policy *policy); 278 279 struct freq_attr **attr; 280 281 /* platform specific boost support code */ 282 bool boost_supported; 283 bool boost_enabled; 284 int (*set_boost)(int state); 285 }; 286 287 /* flags */ 288 #define CPUFREQ_STICKY (1 << 0) /* driver isn't removed even if 289 all ->init() calls failed */ 290 #define CPUFREQ_CONST_LOOPS (1 << 1) /* loops_per_jiffy or other 291 kernel "constants" aren't 292 affected by frequency 293 transitions */ 294 #define CPUFREQ_PM_NO_WARN (1 << 2) /* don't warn on suspend/resume 295 speed mismatches */ 296 297 /* 298 * This should be set by platforms having multiple clock-domains, i.e. 299 * supporting multiple policies. With this sysfs directories of governor would 300 * be created in cpu/cpu<num>/cpufreq/ directory and so they can use the same 301 * governor with different tunables for different clusters. 302 */ 303 #define CPUFREQ_HAVE_GOVERNOR_PER_POLICY (1 << 3) 304 305 /* 306 * Driver will do POSTCHANGE notifications from outside of their ->target() 307 * routine and so must set cpufreq_driver->flags with this flag, so that core 308 * can handle them specially. 309 */ 310 #define CPUFREQ_ASYNC_NOTIFICATION (1 << 4) 311 312 /* 313 * Set by drivers which want cpufreq core to check if CPU is running at a 314 * frequency present in freq-table exposed by the driver. For these drivers if 315 * CPU is found running at an out of table freq, we will try to set it to a freq 316 * from the table. And if that fails, we will stop further boot process by 317 * issuing a BUG_ON(). 318 */ 319 #define CPUFREQ_NEED_INITIAL_FREQ_CHECK (1 << 5) 320 321 int cpufreq_register_driver(struct cpufreq_driver *driver_data); 322 int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); 323 324 const char *cpufreq_get_current_driver(void); 325 void *cpufreq_get_driver_data(void); 326 327 static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, 328 unsigned int min, unsigned int max) 329 { 330 if (policy->min < min) 331 policy->min = min; 332 if (policy->max < min) 333 policy->max = min; 334 if (policy->min > max) 335 policy->min = max; 336 if (policy->max > max) 337 policy->max = max; 338 if (policy->min > policy->max) 339 policy->min = policy->max; 340 return; 341 } 342 343 static inline void 344 cpufreq_verify_within_cpu_limits(struct cpufreq_policy *policy) 345 { 346 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, 347 policy->cpuinfo.max_freq); 348 } 349 350 #ifdef CONFIG_CPU_FREQ 351 void cpufreq_suspend(void); 352 void cpufreq_resume(void); 353 int cpufreq_generic_suspend(struct cpufreq_policy *policy); 354 #else 355 static inline void cpufreq_suspend(void) {} 356 static inline void cpufreq_resume(void) {} 357 #endif 358 359 /********************************************************************* 360 * CPUFREQ NOTIFIER INTERFACE * 361 *********************************************************************/ 362 363 #define CPUFREQ_TRANSITION_NOTIFIER (0) 364 #define CPUFREQ_POLICY_NOTIFIER (1) 365 366 /* Transition notifiers */ 367 #define CPUFREQ_PRECHANGE (0) 368 #define CPUFREQ_POSTCHANGE (1) 369 370 /* Policy Notifiers */ 371 #define CPUFREQ_ADJUST (0) 372 #define CPUFREQ_INCOMPATIBLE (1) 373 #define CPUFREQ_NOTIFY (2) 374 #define CPUFREQ_START (3) 375 #define CPUFREQ_CREATE_POLICY (4) 376 #define CPUFREQ_REMOVE_POLICY (5) 377 378 #ifdef CONFIG_CPU_FREQ 379 int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); 380 int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); 381 382 void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, 383 struct cpufreq_freqs *freqs); 384 void cpufreq_freq_transition_end(struct cpufreq_policy *policy, 385 struct cpufreq_freqs *freqs, int transition_failed); 386 387 #else /* CONFIG_CPU_FREQ */ 388 static inline int cpufreq_register_notifier(struct notifier_block *nb, 389 unsigned int list) 390 { 391 return 0; 392 } 393 static inline int cpufreq_unregister_notifier(struct notifier_block *nb, 394 unsigned int list) 395 { 396 return 0; 397 } 398 #endif /* !CONFIG_CPU_FREQ */ 399 400 /** 401 * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch 402 * safe) 403 * @old: old value 404 * @div: divisor 405 * @mult: multiplier 406 * 407 * 408 * new = old * mult / div 409 */ 410 static inline unsigned long cpufreq_scale(unsigned long old, u_int div, 411 u_int mult) 412 { 413 #if BITS_PER_LONG == 32 414 u64 result = ((u64) old) * ((u64) mult); 415 do_div(result, div); 416 return (unsigned long) result; 417 418 #elif BITS_PER_LONG == 64 419 unsigned long result = old * ((u64) mult); 420 result /= div; 421 return result; 422 #endif 423 } 424 425 /********************************************************************* 426 * CPUFREQ GOVERNORS * 427 *********************************************************************/ 428 429 /* 430 * If (cpufreq_driver->target) exists, the ->governor decides what frequency 431 * within the limits is used. If (cpufreq_driver->setpolicy> exists, these 432 * two generic policies are available: 433 */ 434 #define CPUFREQ_POLICY_POWERSAVE (1) 435 #define CPUFREQ_POLICY_PERFORMANCE (2) 436 437 /* Governor Events */ 438 #define CPUFREQ_GOV_START 1 439 #define CPUFREQ_GOV_STOP 2 440 #define CPUFREQ_GOV_LIMITS 3 441 #define CPUFREQ_GOV_POLICY_INIT 4 442 #define CPUFREQ_GOV_POLICY_EXIT 5 443 444 struct cpufreq_governor { 445 char name[CPUFREQ_NAME_LEN]; 446 int initialized; 447 int (*governor) (struct cpufreq_policy *policy, 448 unsigned int event); 449 ssize_t (*show_setspeed) (struct cpufreq_policy *policy, 450 char *buf); 451 int (*store_setspeed) (struct cpufreq_policy *policy, 452 unsigned int freq); 453 unsigned int max_transition_latency; /* HW must be able to switch to 454 next freq faster than this value in nano secs or we 455 will fallback to performance governor */ 456 struct list_head governor_list; 457 struct module *owner; 458 }; 459 460 /* Pass a target to the cpufreq driver */ 461 int cpufreq_driver_target(struct cpufreq_policy *policy, 462 unsigned int target_freq, 463 unsigned int relation); 464 int __cpufreq_driver_target(struct cpufreq_policy *policy, 465 unsigned int target_freq, 466 unsigned int relation); 467 int cpufreq_register_governor(struct cpufreq_governor *governor); 468 void cpufreq_unregister_governor(struct cpufreq_governor *governor); 469 470 /* CPUFREQ DEFAULT GOVERNOR */ 471 /* 472 * Performance governor is fallback governor if any other gov failed to auto 473 * load due latency restrictions 474 */ 475 #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE 476 extern struct cpufreq_governor cpufreq_gov_performance; 477 #endif 478 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE 479 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) 480 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) 481 extern struct cpufreq_governor cpufreq_gov_powersave; 482 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) 483 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) 484 extern struct cpufreq_governor cpufreq_gov_userspace; 485 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) 486 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) 487 extern struct cpufreq_governor cpufreq_gov_ondemand; 488 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) 489 #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) 490 extern struct cpufreq_governor cpufreq_gov_conservative; 491 #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) 492 #endif 493 494 /********************************************************************* 495 * FREQUENCY TABLE HELPERS * 496 *********************************************************************/ 497 498 /* Special Values of .frequency field */ 499 #define CPUFREQ_ENTRY_INVALID ~0u 500 #define CPUFREQ_TABLE_END ~1u 501 /* Special Values of .flags field */ 502 #define CPUFREQ_BOOST_FREQ (1 << 0) 503 504 struct cpufreq_frequency_table { 505 unsigned int flags; 506 unsigned int driver_data; /* driver specific data, not used by core */ 507 unsigned int frequency; /* kHz - doesn't need to be in ascending 508 * order */ 509 }; 510 511 #if defined(CONFIG_CPU_FREQ) && defined(CONFIG_PM_OPP) 512 int dev_pm_opp_init_cpufreq_table(struct device *dev, 513 struct cpufreq_frequency_table **table); 514 void dev_pm_opp_free_cpufreq_table(struct device *dev, 515 struct cpufreq_frequency_table **table); 516 #else 517 static inline int dev_pm_opp_init_cpufreq_table(struct device *dev, 518 struct cpufreq_frequency_table 519 **table) 520 { 521 return -EINVAL; 522 } 523 524 static inline void dev_pm_opp_free_cpufreq_table(struct device *dev, 525 struct cpufreq_frequency_table 526 **table) 527 { 528 } 529 #endif 530 531 static inline bool cpufreq_next_valid(struct cpufreq_frequency_table **pos) 532 { 533 while ((*pos)->frequency != CPUFREQ_TABLE_END) 534 if ((*pos)->frequency != CPUFREQ_ENTRY_INVALID) 535 return true; 536 else 537 (*pos)++; 538 return false; 539 } 540 541 /* 542 * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table 543 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 544 * @table: the cpufreq_frequency_table * to iterate over. 545 */ 546 547 #define cpufreq_for_each_entry(pos, table) \ 548 for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++) 549 550 /* 551 * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table 552 * excluding CPUFREQ_ENTRY_INVALID frequencies. 553 * @pos: the cpufreq_frequency_table * to use as a loop cursor. 554 * @table: the cpufreq_frequency_table * to iterate over. 555 */ 556 557 #define cpufreq_for_each_valid_entry(pos, table) \ 558 for (pos = table; cpufreq_next_valid(&pos); pos++) 559 560 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 561 struct cpufreq_frequency_table *table); 562 563 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 564 struct cpufreq_frequency_table *table); 565 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy); 566 567 int cpufreq_frequency_table_target(struct cpufreq_policy *policy, 568 struct cpufreq_frequency_table *table, 569 unsigned int target_freq, 570 unsigned int relation, 571 unsigned int *index); 572 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, 573 unsigned int freq); 574 575 ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf); 576 577 #ifdef CONFIG_CPU_FREQ 578 int cpufreq_boost_trigger_state(int state); 579 int cpufreq_boost_supported(void); 580 int cpufreq_boost_enabled(void); 581 #else 582 static inline int cpufreq_boost_trigger_state(int state) 583 { 584 return 0; 585 } 586 static inline int cpufreq_boost_supported(void) 587 { 588 return 0; 589 } 590 static inline int cpufreq_boost_enabled(void) 591 { 592 return 0; 593 } 594 #endif 595 /* the following funtion is for cpufreq core use only */ 596 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); 597 598 /* the following are really really optional */ 599 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; 600 extern struct freq_attr *cpufreq_generic_attr[]; 601 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy, 602 struct cpufreq_frequency_table *table); 603 604 unsigned int cpufreq_generic_get(unsigned int cpu); 605 int cpufreq_generic_init(struct cpufreq_policy *policy, 606 struct cpufreq_frequency_table *table, 607 unsigned int transition_latency); 608 #endif /* _LINUX_CPUFREQ_H */ 609