| 1 | /* |
| 2 | * linux/include/linux/cpufreq.h |
| 3 | * |
| 4 | * Copyright (C) 2001 Russell King |
| 5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> |
| 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 <asm/cputime.h> |
| 15 | #include <linux/mutex.h> |
| 16 | #include <linux/notifier.h> |
| 17 | #include <linux/threads.h> |
| 18 | #include <linux/kobject.h> |
| 19 | #include <linux/sysfs.h> |
| 20 | #include <linux/completion.h> |
| 21 | #include <linux/workqueue.h> |
| 22 | #include <linux/cpumask.h> |
| 23 | #include <asm/div64.h> |
| 24 | |
| 25 | #define CPUFREQ_NAME_LEN 16 |
| 26 | /* Print length for names. Extra 1 space for accomodating '\n' in prints */ |
| 27 | #define CPUFREQ_NAME_PLEN (CPUFREQ_NAME_LEN + 1) |
| 28 | |
| 29 | |
| 30 | /********************************************************************* |
| 31 | * CPUFREQ NOTIFIER INTERFACE * |
| 32 | *********************************************************************/ |
| 33 | |
| 34 | #define CPUFREQ_TRANSITION_NOTIFIER (0) |
| 35 | #define CPUFREQ_POLICY_NOTIFIER (1) |
| 36 | |
| 37 | #ifdef CONFIG_CPU_FREQ |
| 38 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list); |
| 39 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list); |
| 40 | extern void disable_cpufreq(void); |
| 41 | #else /* CONFIG_CPU_FREQ */ |
| 42 | static inline int cpufreq_register_notifier(struct notifier_block *nb, |
| 43 | unsigned int list) |
| 44 | { |
| 45 | return 0; |
| 46 | } |
| 47 | static inline int cpufreq_unregister_notifier(struct notifier_block *nb, |
| 48 | unsigned int list) |
| 49 | { |
| 50 | return 0; |
| 51 | } |
| 52 | static inline void disable_cpufreq(void) { } |
| 53 | #endif /* CONFIG_CPU_FREQ */ |
| 54 | |
| 55 | /* if (cpufreq_driver->target) exists, the ->governor decides what frequency |
| 56 | * within the limits is used. If (cpufreq_driver->setpolicy> exists, these |
| 57 | * two generic policies are available: |
| 58 | */ |
| 59 | |
| 60 | #define CPUFREQ_POLICY_POWERSAVE (1) |
| 61 | #define CPUFREQ_POLICY_PERFORMANCE (2) |
| 62 | |
| 63 | /* Frequency values here are CPU kHz so that hardware which doesn't run |
| 64 | * with some frequencies can complain without having to guess what per |
| 65 | * cent / per mille means. |
| 66 | * Maximum transition latency is in nanoseconds - if it's unknown, |
| 67 | * CPUFREQ_ETERNAL shall be used. |
| 68 | */ |
| 69 | |
| 70 | struct cpufreq_governor; |
| 71 | |
| 72 | /* /sys/devices/system/cpu/cpufreq: entry point for global variables */ |
| 73 | extern struct kobject *cpufreq_global_kobject; |
| 74 | |
| 75 | #define CPUFREQ_ETERNAL (-1) |
| 76 | struct cpufreq_cpuinfo { |
| 77 | unsigned int max_freq; |
| 78 | unsigned int min_freq; |
| 79 | |
| 80 | /* in 10^(-9) s = nanoseconds */ |
| 81 | unsigned int transition_latency; |
| 82 | }; |
| 83 | |
| 84 | struct cpufreq_real_policy { |
| 85 | unsigned int min; /* in kHz */ |
| 86 | unsigned int max; /* in kHz */ |
| 87 | unsigned int policy; /* see above */ |
| 88 | struct cpufreq_governor *governor; /* see below */ |
| 89 | }; |
| 90 | |
| 91 | struct cpufreq_policy { |
| 92 | /* CPUs sharing clock, require sw coordination */ |
| 93 | cpumask_var_t cpus; /* Online CPUs only */ |
| 94 | cpumask_var_t related_cpus; /* Online + Offline CPUs */ |
| 95 | |
| 96 | unsigned int shared_type; /* ACPI: ANY or ALL affected CPUs |
| 97 | should set cpufreq */ |
| 98 | unsigned int cpu; /* cpu nr of CPU managing this policy */ |
| 99 | unsigned int last_cpu; /* cpu nr of previous CPU that managed |
| 100 | * this policy */ |
| 101 | struct cpufreq_cpuinfo cpuinfo;/* see above */ |
| 102 | |
| 103 | unsigned int min; /* in kHz */ |
| 104 | unsigned int max; /* in kHz */ |
| 105 | unsigned int cur; /* in kHz, only needed if cpufreq |
| 106 | * governors are used */ |
| 107 | unsigned int policy; /* see above */ |
| 108 | struct cpufreq_governor *governor; /* see below */ |
| 109 | void *governor_data; |
| 110 | |
| 111 | struct work_struct update; /* if update_policy() needs to be |
| 112 | * called, but you're in IRQ context */ |
| 113 | |
| 114 | struct cpufreq_real_policy user_policy; |
| 115 | |
| 116 | struct kobject kobj; |
| 117 | struct completion kobj_unregister; |
| 118 | }; |
| 119 | |
| 120 | #define CPUFREQ_ADJUST (0) |
| 121 | #define CPUFREQ_INCOMPATIBLE (1) |
| 122 | #define CPUFREQ_NOTIFY (2) |
| 123 | #define CPUFREQ_START (3) |
| 124 | #define CPUFREQ_UPDATE_POLICY_CPU (4) |
| 125 | |
| 126 | /* Only for ACPI */ |
| 127 | #define CPUFREQ_SHARED_TYPE_NONE (0) /* None */ |
| 128 | #define CPUFREQ_SHARED_TYPE_HW (1) /* HW does needed coordination */ |
| 129 | #define CPUFREQ_SHARED_TYPE_ALL (2) /* All dependent CPUs should set freq */ |
| 130 | #define CPUFREQ_SHARED_TYPE_ANY (3) /* Freq can be set from any dependent CPU*/ |
| 131 | |
| 132 | static inline bool policy_is_shared(struct cpufreq_policy *policy) |
| 133 | { |
| 134 | return cpumask_weight(policy->cpus) > 1; |
| 135 | } |
| 136 | |
| 137 | /******************** cpufreq transition notifiers *******************/ |
| 138 | |
| 139 | #define CPUFREQ_PRECHANGE (0) |
| 140 | #define CPUFREQ_POSTCHANGE (1) |
| 141 | #define CPUFREQ_RESUMECHANGE (8) |
| 142 | #define CPUFREQ_SUSPENDCHANGE (9) |
| 143 | |
| 144 | struct cpufreq_freqs { |
| 145 | unsigned int cpu; /* cpu nr */ |
| 146 | unsigned int old; |
| 147 | unsigned int new; |
| 148 | u8 flags; /* flags of cpufreq_driver, see below. */ |
| 149 | }; |
| 150 | |
| 151 | |
| 152 | /** |
| 153 | * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch safe) |
| 154 | * @old: old value |
| 155 | * @div: divisor |
| 156 | * @mult: multiplier |
| 157 | * |
| 158 | * |
| 159 | * new = old * mult / div |
| 160 | */ |
| 161 | static inline unsigned long cpufreq_scale(unsigned long old, u_int div, u_int mult) |
| 162 | { |
| 163 | #if BITS_PER_LONG == 32 |
| 164 | |
| 165 | u64 result = ((u64) old) * ((u64) mult); |
| 166 | do_div(result, div); |
| 167 | return (unsigned long) result; |
| 168 | |
| 169 | #elif BITS_PER_LONG == 64 |
| 170 | |
| 171 | unsigned long result = old * ((u64) mult); |
| 172 | result /= div; |
| 173 | return result; |
| 174 | |
| 175 | #endif |
| 176 | }; |
| 177 | |
| 178 | /********************************************************************* |
| 179 | * CPUFREQ GOVERNORS * |
| 180 | *********************************************************************/ |
| 181 | |
| 182 | #define CPUFREQ_GOV_START 1 |
| 183 | #define CPUFREQ_GOV_STOP 2 |
| 184 | #define CPUFREQ_GOV_LIMITS 3 |
| 185 | #define CPUFREQ_GOV_POLICY_INIT 4 |
| 186 | #define CPUFREQ_GOV_POLICY_EXIT 5 |
| 187 | |
| 188 | struct cpufreq_governor { |
| 189 | char name[CPUFREQ_NAME_LEN]; |
| 190 | int initialized; |
| 191 | int (*governor) (struct cpufreq_policy *policy, |
| 192 | unsigned int event); |
| 193 | ssize_t (*show_setspeed) (struct cpufreq_policy *policy, |
| 194 | char *buf); |
| 195 | int (*store_setspeed) (struct cpufreq_policy *policy, |
| 196 | unsigned int freq); |
| 197 | unsigned int max_transition_latency; /* HW must be able to switch to |
| 198 | next freq faster than this value in nano secs or we |
| 199 | will fallback to performance governor */ |
| 200 | struct list_head governor_list; |
| 201 | struct module *owner; |
| 202 | }; |
| 203 | |
| 204 | /* |
| 205 | * Pass a target to the cpufreq driver. |
| 206 | */ |
| 207 | extern int cpufreq_driver_target(struct cpufreq_policy *policy, |
| 208 | unsigned int target_freq, |
| 209 | unsigned int relation); |
| 210 | extern int __cpufreq_driver_target(struct cpufreq_policy *policy, |
| 211 | unsigned int target_freq, |
| 212 | unsigned int relation); |
| 213 | |
| 214 | |
| 215 | extern int __cpufreq_driver_getavg(struct cpufreq_policy *policy, |
| 216 | unsigned int cpu); |
| 217 | |
| 218 | int cpufreq_register_governor(struct cpufreq_governor *governor); |
| 219 | void cpufreq_unregister_governor(struct cpufreq_governor *governor); |
| 220 | |
| 221 | |
| 222 | /********************************************************************* |
| 223 | * CPUFREQ DRIVER INTERFACE * |
| 224 | *********************************************************************/ |
| 225 | |
| 226 | #define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */ |
| 227 | #define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */ |
| 228 | |
| 229 | struct freq_attr; |
| 230 | |
| 231 | struct cpufreq_driver { |
| 232 | struct module *owner; |
| 233 | char name[CPUFREQ_NAME_LEN]; |
| 234 | u8 flags; |
| 235 | /* |
| 236 | * This should be set by platforms having multiple clock-domains, i.e. |
| 237 | * supporting multiple policies. With this sysfs directories of governor |
| 238 | * would be created in cpu/cpu<num>/cpufreq/ directory and so they can |
| 239 | * use the same governor with different tunables for different clusters. |
| 240 | */ |
| 241 | bool have_governor_per_policy; |
| 242 | |
| 243 | /* needed by all drivers */ |
| 244 | int (*init) (struct cpufreq_policy *policy); |
| 245 | int (*verify) (struct cpufreq_policy *policy); |
| 246 | |
| 247 | /* define one out of two */ |
| 248 | int (*setpolicy) (struct cpufreq_policy *policy); |
| 249 | int (*target) (struct cpufreq_policy *policy, |
| 250 | unsigned int target_freq, |
| 251 | unsigned int relation); |
| 252 | |
| 253 | /* should be defined, if possible */ |
| 254 | unsigned int (*get) (unsigned int cpu); |
| 255 | |
| 256 | /* optional */ |
| 257 | unsigned int (*getavg) (struct cpufreq_policy *policy, |
| 258 | unsigned int cpu); |
| 259 | int (*bios_limit) (int cpu, unsigned int *limit); |
| 260 | |
| 261 | int (*exit) (struct cpufreq_policy *policy); |
| 262 | int (*suspend) (struct cpufreq_policy *policy); |
| 263 | int (*resume) (struct cpufreq_policy *policy); |
| 264 | struct freq_attr **attr; |
| 265 | }; |
| 266 | |
| 267 | /* flags */ |
| 268 | |
| 269 | #define CPUFREQ_STICKY 0x01 /* the driver isn't removed even if |
| 270 | * all ->init() calls failed */ |
| 271 | #define CPUFREQ_CONST_LOOPS 0x02 /* loops_per_jiffy or other kernel |
| 272 | * "constants" aren't affected by |
| 273 | * frequency transitions */ |
| 274 | #define CPUFREQ_PM_NO_WARN 0x04 /* don't warn on suspend/resume speed |
| 275 | * mismatches */ |
| 276 | |
| 277 | int cpufreq_register_driver(struct cpufreq_driver *driver_data); |
| 278 | int cpufreq_unregister_driver(struct cpufreq_driver *driver_data); |
| 279 | |
| 280 | |
| 281 | void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state); |
| 282 | |
| 283 | |
| 284 | static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, unsigned int min, unsigned int max) |
| 285 | { |
| 286 | if (policy->min < min) |
| 287 | policy->min = min; |
| 288 | if (policy->max < min) |
| 289 | policy->max = min; |
| 290 | if (policy->min > max) |
| 291 | policy->min = max; |
| 292 | if (policy->max > max) |
| 293 | policy->max = max; |
| 294 | if (policy->min > policy->max) |
| 295 | policy->min = policy->max; |
| 296 | return; |
| 297 | } |
| 298 | |
| 299 | struct freq_attr { |
| 300 | struct attribute attr; |
| 301 | ssize_t (*show)(struct cpufreq_policy *, char *); |
| 302 | ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count); |
| 303 | }; |
| 304 | |
| 305 | #define cpufreq_freq_attr_ro(_name) \ |
| 306 | static struct freq_attr _name = \ |
| 307 | __ATTR(_name, 0444, show_##_name, NULL) |
| 308 | |
| 309 | #define cpufreq_freq_attr_ro_perm(_name, _perm) \ |
| 310 | static struct freq_attr _name = \ |
| 311 | __ATTR(_name, _perm, show_##_name, NULL) |
| 312 | |
| 313 | #define cpufreq_freq_attr_rw(_name) \ |
| 314 | static struct freq_attr _name = \ |
| 315 | __ATTR(_name, 0644, show_##_name, store_##_name) |
| 316 | |
| 317 | struct global_attr { |
| 318 | struct attribute attr; |
| 319 | ssize_t (*show)(struct kobject *kobj, |
| 320 | struct attribute *attr, char *buf); |
| 321 | ssize_t (*store)(struct kobject *a, struct attribute *b, |
| 322 | const char *c, size_t count); |
| 323 | }; |
| 324 | |
| 325 | #define define_one_global_ro(_name) \ |
| 326 | static struct global_attr _name = \ |
| 327 | __ATTR(_name, 0444, show_##_name, NULL) |
| 328 | |
| 329 | #define define_one_global_rw(_name) \ |
| 330 | static struct global_attr _name = \ |
| 331 | __ATTR(_name, 0644, show_##_name, store_##_name) |
| 332 | |
| 333 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu); |
| 334 | void cpufreq_cpu_put(struct cpufreq_policy *data); |
| 335 | const char *cpufreq_get_current_driver(void); |
| 336 | |
| 337 | /********************************************************************* |
| 338 | * CPUFREQ 2.6. INTERFACE * |
| 339 | *********************************************************************/ |
| 340 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu); |
| 341 | int cpufreq_update_policy(unsigned int cpu); |
| 342 | bool have_governor_per_policy(void); |
| 343 | |
| 344 | #ifdef CONFIG_CPU_FREQ |
| 345 | /* query the current CPU frequency (in kHz). If zero, cpufreq couldn't detect it */ |
| 346 | unsigned int cpufreq_get(unsigned int cpu); |
| 347 | #else |
| 348 | static inline unsigned int cpufreq_get(unsigned int cpu) |
| 349 | { |
| 350 | return 0; |
| 351 | } |
| 352 | #endif |
| 353 | |
| 354 | /* query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it */ |
| 355 | #ifdef CONFIG_CPU_FREQ |
| 356 | unsigned int cpufreq_quick_get(unsigned int cpu); |
| 357 | unsigned int cpufreq_quick_get_max(unsigned int cpu); |
| 358 | #else |
| 359 | static inline unsigned int cpufreq_quick_get(unsigned int cpu) |
| 360 | { |
| 361 | return 0; |
| 362 | } |
| 363 | static inline unsigned int cpufreq_quick_get_max(unsigned int cpu) |
| 364 | { |
| 365 | return 0; |
| 366 | } |
| 367 | #endif |
| 368 | |
| 369 | |
| 370 | /********************************************************************* |
| 371 | * CPUFREQ DEFAULT GOVERNOR * |
| 372 | *********************************************************************/ |
| 373 | |
| 374 | |
| 375 | /* |
| 376 | Performance governor is fallback governor if any other gov failed to |
| 377 | auto load due latency restrictions |
| 378 | */ |
| 379 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE |
| 380 | extern struct cpufreq_governor cpufreq_gov_performance; |
| 381 | #endif |
| 382 | #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE |
| 383 | #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_performance) |
| 384 | #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE) |
| 385 | extern struct cpufreq_governor cpufreq_gov_powersave; |
| 386 | #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_powersave) |
| 387 | #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE) |
| 388 | extern struct cpufreq_governor cpufreq_gov_userspace; |
| 389 | #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_userspace) |
| 390 | #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND) |
| 391 | extern struct cpufreq_governor cpufreq_gov_ondemand; |
| 392 | #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_ondemand) |
| 393 | #elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE) |
| 394 | extern struct cpufreq_governor cpufreq_gov_conservative; |
| 395 | #define CPUFREQ_DEFAULT_GOVERNOR (&cpufreq_gov_conservative) |
| 396 | #endif |
| 397 | |
| 398 | |
| 399 | /********************************************************************* |
| 400 | * FREQUENCY TABLE HELPERS * |
| 401 | *********************************************************************/ |
| 402 | |
| 403 | #define CPUFREQ_ENTRY_INVALID ~0 |
| 404 | #define CPUFREQ_TABLE_END ~1 |
| 405 | |
| 406 | struct cpufreq_frequency_table { |
| 407 | unsigned int index; /* any */ |
| 408 | unsigned int frequency; /* kHz - doesn't need to be in ascending |
| 409 | * order */ |
| 410 | }; |
| 411 | |
| 412 | int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, |
| 413 | struct cpufreq_frequency_table *table); |
| 414 | |
| 415 | int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, |
| 416 | struct cpufreq_frequency_table *table); |
| 417 | |
| 418 | int cpufreq_frequency_table_target(struct cpufreq_policy *policy, |
| 419 | struct cpufreq_frequency_table *table, |
| 420 | unsigned int target_freq, |
| 421 | unsigned int relation, |
| 422 | unsigned int *index); |
| 423 | |
| 424 | /* the following 3 funtions are for cpufreq core use only */ |
| 425 | struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu); |
| 426 | |
| 427 | /* the following are really really optional */ |
| 428 | extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs; |
| 429 | |
| 430 | void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table, |
| 431 | unsigned int cpu); |
| 432 | void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy); |
| 433 | |
| 434 | void cpufreq_frequency_table_put_attr(unsigned int cpu); |
| 435 | #endif /* _LINUX_CPUFREQ_H */ |