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