Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
e00e56df | 29 | #include <linux/syscore_ops.h> |
5ff0a268 | 30 | #include <linux/tick.h> |
6f4f2723 TR |
31 | #include <trace/events/power.h> |
32 | ||
1da177e4 | 33 | /** |
cd878479 | 34 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
35 | * level driver of CPUFreq support, and its spinlock. This lock |
36 | * also protects the cpufreq_cpu_data array. | |
37 | */ | |
1c3d85dd | 38 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 39 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
8414809c | 40 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback); |
bb176f7d VK |
41 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
42 | static DEFINE_MUTEX(cpufreq_governor_lock); | |
c88a1f8b | 43 | static LIST_HEAD(cpufreq_policy_list); |
bb176f7d | 44 | |
084f3493 TR |
45 | #ifdef CONFIG_HOTPLUG_CPU |
46 | /* This one keeps track of the previously set governor of a removed CPU */ | |
e77b89f1 | 47 | static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor); |
084f3493 | 48 | #endif |
1da177e4 | 49 | |
5a01f2e8 VP |
50 | /* |
51 | * cpu_policy_rwsem is a per CPU reader-writer semaphore designed to cure | |
52 | * all cpufreq/hotplug/workqueue/etc related lock issues. | |
53 | * | |
54 | * The rules for this semaphore: | |
55 | * - Any routine that wants to read from the policy structure will | |
56 | * do a down_read on this semaphore. | |
57 | * - Any routine that will write to the policy structure and/or may take away | |
58 | * the policy altogether (eg. CPU hotplug), will hold this lock in write | |
59 | * mode before doing so. | |
60 | * | |
61 | * Additional rules: | |
5a01f2e8 VP |
62 | * - Governor routines that can be called in cpufreq hotplug path should not |
63 | * take this sem as top level hotplug notifier handler takes this. | |
395913d0 MD |
64 | * - Lock should not be held across |
65 | * __cpufreq_governor(data, CPUFREQ_GOV_STOP); | |
5a01f2e8 | 66 | */ |
f1625066 | 67 | static DEFINE_PER_CPU(int, cpufreq_policy_cpu); |
5a01f2e8 VP |
68 | static DEFINE_PER_CPU(struct rw_semaphore, cpu_policy_rwsem); |
69 | ||
70 | #define lock_policy_rwsem(mode, cpu) \ | |
fa1d8af4 | 71 | static int lock_policy_rwsem_##mode(int cpu) \ |
5a01f2e8 | 72 | { \ |
f1625066 | 73 | int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu); \ |
5a01f2e8 VP |
74 | BUG_ON(policy_cpu == -1); \ |
75 | down_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \ | |
5a01f2e8 VP |
76 | \ |
77 | return 0; \ | |
78 | } | |
79 | ||
80 | lock_policy_rwsem(read, cpu); | |
5a01f2e8 | 81 | lock_policy_rwsem(write, cpu); |
5a01f2e8 | 82 | |
fa1d8af4 VK |
83 | #define unlock_policy_rwsem(mode, cpu) \ |
84 | static void unlock_policy_rwsem_##mode(int cpu) \ | |
85 | { \ | |
86 | int policy_cpu = per_cpu(cpufreq_policy_cpu, cpu); \ | |
87 | BUG_ON(policy_cpu == -1); \ | |
88 | up_##mode(&per_cpu(cpu_policy_rwsem, policy_cpu)); \ | |
5a01f2e8 | 89 | } |
5a01f2e8 | 90 | |
fa1d8af4 VK |
91 | unlock_policy_rwsem(read, cpu); |
92 | unlock_policy_rwsem(write, cpu); | |
5a01f2e8 | 93 | |
1da177e4 | 94 | /* internal prototypes */ |
29464f28 DJ |
95 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
96 | unsigned int event); | |
5a01f2e8 | 97 | static unsigned int __cpufreq_get(unsigned int cpu); |
65f27f38 | 98 | static void handle_update(struct work_struct *work); |
1da177e4 LT |
99 | |
100 | /** | |
32ee8c3e DJ |
101 | * Two notifier lists: the "policy" list is involved in the |
102 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
103 | * "transition" list for kernel code that needs to handle |
104 | * changes to devices when the CPU clock speed changes. | |
105 | * The mutex locks both lists. | |
106 | */ | |
e041c683 | 107 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 108 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 109 | |
74212ca4 | 110 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
111 | static int __init init_cpufreq_transition_notifier_list(void) |
112 | { | |
113 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 114 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
115 | return 0; |
116 | } | |
b3438f82 | 117 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 118 | |
a7b422cd | 119 | static int off __read_mostly; |
da584455 | 120 | static int cpufreq_disabled(void) |
a7b422cd KRW |
121 | { |
122 | return off; | |
123 | } | |
124 | void disable_cpufreq(void) | |
125 | { | |
126 | off = 1; | |
127 | } | |
1da177e4 | 128 | static LIST_HEAD(cpufreq_governor_list); |
29464f28 | 129 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 130 | |
4d5dcc42 VK |
131 | bool have_governor_per_policy(void) |
132 | { | |
1c3d85dd | 133 | return cpufreq_driver->have_governor_per_policy; |
4d5dcc42 | 134 | } |
3f869d6d | 135 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 136 | |
944e9a03 VK |
137 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
138 | { | |
139 | if (have_governor_per_policy()) | |
140 | return &policy->kobj; | |
141 | else | |
142 | return cpufreq_global_kobject; | |
143 | } | |
144 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
145 | ||
72a4ce34 VK |
146 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
147 | { | |
148 | u64 idle_time; | |
149 | u64 cur_wall_time; | |
150 | u64 busy_time; | |
151 | ||
152 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
153 | ||
154 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
155 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
156 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
157 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
158 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
159 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
160 | ||
161 | idle_time = cur_wall_time - busy_time; | |
162 | if (wall) | |
163 | *wall = cputime_to_usecs(cur_wall_time); | |
164 | ||
165 | return cputime_to_usecs(idle_time); | |
166 | } | |
167 | ||
168 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
169 | { | |
170 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
171 | ||
172 | if (idle_time == -1ULL) | |
173 | return get_cpu_idle_time_jiffy(cpu, wall); | |
174 | else if (!io_busy) | |
175 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
176 | ||
177 | return idle_time; | |
178 | } | |
179 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
180 | ||
a9144436 | 181 | static struct cpufreq_policy *__cpufreq_cpu_get(unsigned int cpu, bool sysfs) |
1da177e4 | 182 | { |
3a3e9e06 | 183 | struct cpufreq_policy *policy; |
1da177e4 LT |
184 | unsigned long flags; |
185 | ||
7a6aedfa | 186 | if (cpu >= nr_cpu_ids) |
1da177e4 LT |
187 | goto err_out; |
188 | ||
189 | /* get the cpufreq driver */ | |
1c3d85dd | 190 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 191 | |
1c3d85dd | 192 | if (!cpufreq_driver) |
1da177e4 LT |
193 | goto err_out_unlock; |
194 | ||
1c3d85dd | 195 | if (!try_module_get(cpufreq_driver->owner)) |
1da177e4 LT |
196 | goto err_out_unlock; |
197 | ||
1da177e4 | 198 | /* get the CPU */ |
3a3e9e06 | 199 | policy = per_cpu(cpufreq_cpu_data, cpu); |
1da177e4 | 200 | |
3a3e9e06 | 201 | if (!policy) |
1da177e4 LT |
202 | goto err_out_put_module; |
203 | ||
3a3e9e06 | 204 | if (!sysfs && !kobject_get(&policy->kobj)) |
1da177e4 LT |
205 | goto err_out_put_module; |
206 | ||
0d1857a1 | 207 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
3a3e9e06 | 208 | return policy; |
1da177e4 | 209 | |
7d5e350f | 210 | err_out_put_module: |
1c3d85dd | 211 | module_put(cpufreq_driver->owner); |
5800043b | 212 | err_out_unlock: |
1c3d85dd | 213 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
7d5e350f | 214 | err_out: |
1da177e4 LT |
215 | return NULL; |
216 | } | |
a9144436 SB |
217 | |
218 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) | |
219 | { | |
d5aaffa9 DB |
220 | if (cpufreq_disabled()) |
221 | return NULL; | |
222 | ||
a9144436 SB |
223 | return __cpufreq_cpu_get(cpu, false); |
224 | } | |
1da177e4 LT |
225 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
226 | ||
a9144436 SB |
227 | static struct cpufreq_policy *cpufreq_cpu_get_sysfs(unsigned int cpu) |
228 | { | |
229 | return __cpufreq_cpu_get(cpu, true); | |
230 | } | |
231 | ||
3a3e9e06 | 232 | static void __cpufreq_cpu_put(struct cpufreq_policy *policy, bool sysfs) |
a9144436 SB |
233 | { |
234 | if (!sysfs) | |
3a3e9e06 | 235 | kobject_put(&policy->kobj); |
1c3d85dd | 236 | module_put(cpufreq_driver->owner); |
a9144436 | 237 | } |
7d5e350f | 238 | |
3a3e9e06 | 239 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 240 | { |
d5aaffa9 DB |
241 | if (cpufreq_disabled()) |
242 | return; | |
243 | ||
3a3e9e06 | 244 | __cpufreq_cpu_put(policy, false); |
1da177e4 LT |
245 | } |
246 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
247 | ||
3a3e9e06 | 248 | static void cpufreq_cpu_put_sysfs(struct cpufreq_policy *policy) |
a9144436 | 249 | { |
3a3e9e06 | 250 | __cpufreq_cpu_put(policy, true); |
a9144436 | 251 | } |
1da177e4 | 252 | |
1da177e4 LT |
253 | /********************************************************************* |
254 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
255 | *********************************************************************/ | |
256 | ||
257 | /** | |
258 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
259 | * | |
260 | * This function alters the system "loops_per_jiffy" for the clock | |
261 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 262 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
263 | * per-CPU loops_per_jiffy value wherever possible. |
264 | */ | |
265 | #ifndef CONFIG_SMP | |
266 | static unsigned long l_p_j_ref; | |
bb176f7d | 267 | static unsigned int l_p_j_ref_freq; |
1da177e4 | 268 | |
858119e1 | 269 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 LT |
270 | { |
271 | if (ci->flags & CPUFREQ_CONST_LOOPS) | |
272 | return; | |
273 | ||
274 | if (!l_p_j_ref_freq) { | |
275 | l_p_j_ref = loops_per_jiffy; | |
276 | l_p_j_ref_freq = ci->old; | |
2d06d8c4 | 277 | pr_debug("saving %lu as reference value for loops_per_jiffy; " |
e08f5f5b | 278 | "freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq); |
1da177e4 | 279 | } |
bb176f7d | 280 | if ((val == CPUFREQ_POSTCHANGE && ci->old != ci->new) || |
42d4dc3f | 281 | (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) { |
e08f5f5b GS |
282 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
283 | ci->new); | |
2d06d8c4 | 284 | pr_debug("scaling loops_per_jiffy to %lu " |
e08f5f5b | 285 | "for frequency %u kHz\n", loops_per_jiffy, ci->new); |
1da177e4 LT |
286 | } |
287 | } | |
288 | #else | |
e08f5f5b GS |
289 | static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
290 | { | |
291 | return; | |
292 | } | |
1da177e4 LT |
293 | #endif |
294 | ||
0956df9c | 295 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 296 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
297 | { |
298 | BUG_ON(irqs_disabled()); | |
299 | ||
d5aaffa9 DB |
300 | if (cpufreq_disabled()) |
301 | return; | |
302 | ||
1c3d85dd | 303 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 304 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e4472cb3 | 305 | state, freqs->new); |
1da177e4 | 306 | |
1da177e4 | 307 | switch (state) { |
e4472cb3 | 308 | |
1da177e4 | 309 | case CPUFREQ_PRECHANGE: |
266c13d7 VK |
310 | if (WARN(policy->transition_ongoing == |
311 | cpumask_weight(policy->cpus), | |
7c30ed53 VK |
312 | "In middle of another frequency transition\n")) |
313 | return; | |
314 | ||
266c13d7 | 315 | policy->transition_ongoing++; |
7c30ed53 | 316 | |
32ee8c3e | 317 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
318 | * which is not equal to what the cpufreq core thinks is |
319 | * "old frequency". | |
1da177e4 | 320 | */ |
1c3d85dd | 321 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
322 | if ((policy) && (policy->cpu == freqs->cpu) && |
323 | (policy->cur) && (policy->cur != freqs->old)) { | |
2d06d8c4 | 324 | pr_debug("Warning: CPU frequency is" |
e4472cb3 DJ |
325 | " %u, cpufreq assumed %u kHz.\n", |
326 | freqs->old, policy->cur); | |
327 | freqs->old = policy->cur; | |
1da177e4 LT |
328 | } |
329 | } | |
b4dfdbb3 | 330 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 331 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
332 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
333 | break; | |
e4472cb3 | 334 | |
1da177e4 | 335 | case CPUFREQ_POSTCHANGE: |
7c30ed53 VK |
336 | if (WARN(!policy->transition_ongoing, |
337 | "No frequency transition in progress\n")) | |
338 | return; | |
339 | ||
266c13d7 | 340 | policy->transition_ongoing--; |
7c30ed53 | 341 | |
1da177e4 | 342 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); |
2d06d8c4 | 343 | pr_debug("FREQ: %lu - CPU: %lu", (unsigned long)freqs->new, |
6f4f2723 | 344 | (unsigned long)freqs->cpu); |
25e41933 | 345 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 346 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 347 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
348 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
349 | policy->cur = freqs->new; | |
1da177e4 LT |
350 | break; |
351 | } | |
1da177e4 | 352 | } |
bb176f7d | 353 | |
b43a7ffb VK |
354 | /** |
355 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
356 | * on frequency transition. | |
357 | * | |
358 | * This function calls the transition notifiers and the "adjust_jiffies" | |
359 | * function. It is called twice on all CPU frequency changes that have | |
360 | * external effects. | |
361 | */ | |
362 | void cpufreq_notify_transition(struct cpufreq_policy *policy, | |
363 | struct cpufreq_freqs *freqs, unsigned int state) | |
364 | { | |
365 | for_each_cpu(freqs->cpu, policy->cpus) | |
366 | __cpufreq_notify_transition(policy, freqs, state); | |
367 | } | |
1da177e4 LT |
368 | EXPORT_SYMBOL_GPL(cpufreq_notify_transition); |
369 | ||
370 | ||
1da177e4 LT |
371 | /********************************************************************* |
372 | * SYSFS INTERFACE * | |
373 | *********************************************************************/ | |
374 | ||
3bcb09a3 JF |
375 | static struct cpufreq_governor *__find_governor(const char *str_governor) |
376 | { | |
377 | struct cpufreq_governor *t; | |
378 | ||
379 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) | |
29464f28 | 380 | if (!strnicmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
381 | return t; |
382 | ||
383 | return NULL; | |
384 | } | |
385 | ||
1da177e4 LT |
386 | /** |
387 | * cpufreq_parse_governor - parse a governor string | |
388 | */ | |
905d77cd | 389 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
390 | struct cpufreq_governor **governor) |
391 | { | |
3bcb09a3 | 392 | int err = -EINVAL; |
1c3d85dd RW |
393 | |
394 | if (!cpufreq_driver) | |
3bcb09a3 JF |
395 | goto out; |
396 | ||
1c3d85dd | 397 | if (cpufreq_driver->setpolicy) { |
1da177e4 LT |
398 | if (!strnicmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
399 | *policy = CPUFREQ_POLICY_PERFORMANCE; | |
3bcb09a3 | 400 | err = 0; |
e08f5f5b GS |
401 | } else if (!strnicmp(str_governor, "powersave", |
402 | CPUFREQ_NAME_LEN)) { | |
1da177e4 | 403 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 404 | err = 0; |
1da177e4 | 405 | } |
1c3d85dd | 406 | } else if (cpufreq_driver->target) { |
1da177e4 | 407 | struct cpufreq_governor *t; |
3bcb09a3 | 408 | |
3fc54d37 | 409 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 JF |
410 | |
411 | t = __find_governor(str_governor); | |
412 | ||
ea714970 | 413 | if (t == NULL) { |
1a8e1463 | 414 | int ret; |
ea714970 | 415 | |
1a8e1463 KC |
416 | mutex_unlock(&cpufreq_governor_mutex); |
417 | ret = request_module("cpufreq_%s", str_governor); | |
418 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 419 | |
1a8e1463 KC |
420 | if (ret == 0) |
421 | t = __find_governor(str_governor); | |
ea714970 JF |
422 | } |
423 | ||
3bcb09a3 JF |
424 | if (t != NULL) { |
425 | *governor = t; | |
426 | err = 0; | |
1da177e4 | 427 | } |
3bcb09a3 | 428 | |
3fc54d37 | 429 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 430 | } |
29464f28 | 431 | out: |
3bcb09a3 | 432 | return err; |
1da177e4 | 433 | } |
1da177e4 | 434 | |
1da177e4 | 435 | /** |
e08f5f5b GS |
436 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
437 | * print out cpufreq information | |
1da177e4 LT |
438 | * |
439 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
440 | * "unsigned int". | |
441 | */ | |
442 | ||
32ee8c3e DJ |
443 | #define show_one(file_name, object) \ |
444 | static ssize_t show_##file_name \ | |
905d77cd | 445 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 446 | { \ |
29464f28 | 447 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
448 | } |
449 | ||
450 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
451 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 452 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
453 | show_one(scaling_min_freq, min); |
454 | show_one(scaling_max_freq, max); | |
455 | show_one(scaling_cur_freq, cur); | |
456 | ||
3a3e9e06 VK |
457 | static int __cpufreq_set_policy(struct cpufreq_policy *policy, |
458 | struct cpufreq_policy *new_policy); | |
7970e08b | 459 | |
1da177e4 LT |
460 | /** |
461 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
462 | */ | |
463 | #define store_one(file_name, object) \ | |
464 | static ssize_t store_##file_name \ | |
905d77cd | 465 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 466 | { \ |
f55c9c26 | 467 | unsigned int ret; \ |
1da177e4 LT |
468 | struct cpufreq_policy new_policy; \ |
469 | \ | |
470 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ | |
471 | if (ret) \ | |
472 | return -EINVAL; \ | |
473 | \ | |
29464f28 | 474 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
475 | if (ret != 1) \ |
476 | return -EINVAL; \ | |
477 | \ | |
7970e08b TR |
478 | ret = __cpufreq_set_policy(policy, &new_policy); \ |
479 | policy->user_policy.object = policy->object; \ | |
1da177e4 LT |
480 | \ |
481 | return ret ? ret : count; \ | |
482 | } | |
483 | ||
29464f28 DJ |
484 | store_one(scaling_min_freq, min); |
485 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
486 | |
487 | /** | |
488 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
489 | */ | |
905d77cd DJ |
490 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
491 | char *buf) | |
1da177e4 | 492 | { |
5a01f2e8 | 493 | unsigned int cur_freq = __cpufreq_get(policy->cpu); |
1da177e4 LT |
494 | if (!cur_freq) |
495 | return sprintf(buf, "<unknown>"); | |
496 | return sprintf(buf, "%u\n", cur_freq); | |
497 | } | |
498 | ||
1da177e4 LT |
499 | /** |
500 | * show_scaling_governor - show the current policy for the specified CPU | |
501 | */ | |
905d77cd | 502 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 503 | { |
29464f28 | 504 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
505 | return sprintf(buf, "powersave\n"); |
506 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
507 | return sprintf(buf, "performance\n"); | |
508 | else if (policy->governor) | |
4b972f0b | 509 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 510 | policy->governor->name); |
1da177e4 LT |
511 | return -EINVAL; |
512 | } | |
513 | ||
1da177e4 LT |
514 | /** |
515 | * store_scaling_governor - store policy for the specified CPU | |
516 | */ | |
905d77cd DJ |
517 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
518 | const char *buf, size_t count) | |
1da177e4 | 519 | { |
f55c9c26 | 520 | unsigned int ret; |
1da177e4 LT |
521 | char str_governor[16]; |
522 | struct cpufreq_policy new_policy; | |
523 | ||
524 | ret = cpufreq_get_policy(&new_policy, policy->cpu); | |
525 | if (ret) | |
526 | return ret; | |
527 | ||
29464f28 | 528 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
529 | if (ret != 1) |
530 | return -EINVAL; | |
531 | ||
e08f5f5b GS |
532 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
533 | &new_policy.governor)) | |
1da177e4 LT |
534 | return -EINVAL; |
535 | ||
bb176f7d VK |
536 | /* |
537 | * Do not use cpufreq_set_policy here or the user_policy.max | |
538 | * will be wrongly overridden | |
539 | */ | |
7970e08b TR |
540 | ret = __cpufreq_set_policy(policy, &new_policy); |
541 | ||
542 | policy->user_policy.policy = policy->policy; | |
543 | policy->user_policy.governor = policy->governor; | |
7970e08b | 544 | |
e08f5f5b GS |
545 | if (ret) |
546 | return ret; | |
547 | else | |
548 | return count; | |
1da177e4 LT |
549 | } |
550 | ||
551 | /** | |
552 | * show_scaling_driver - show the cpufreq driver currently loaded | |
553 | */ | |
905d77cd | 554 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 555 | { |
1c3d85dd | 556 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
557 | } |
558 | ||
559 | /** | |
560 | * show_scaling_available_governors - show the available CPUfreq governors | |
561 | */ | |
905d77cd DJ |
562 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
563 | char *buf) | |
1da177e4 LT |
564 | { |
565 | ssize_t i = 0; | |
566 | struct cpufreq_governor *t; | |
567 | ||
1c3d85dd | 568 | if (!cpufreq_driver->target) { |
1da177e4 LT |
569 | i += sprintf(buf, "performance powersave"); |
570 | goto out; | |
571 | } | |
572 | ||
573 | list_for_each_entry(t, &cpufreq_governor_list, governor_list) { | |
29464f28 DJ |
574 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
575 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 576 | goto out; |
4b972f0b | 577 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 578 | } |
7d5e350f | 579 | out: |
1da177e4 LT |
580 | i += sprintf(&buf[i], "\n"); |
581 | return i; | |
582 | } | |
e8628dd0 | 583 | |
f4fd3797 | 584 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
585 | { |
586 | ssize_t i = 0; | |
587 | unsigned int cpu; | |
588 | ||
835481d9 | 589 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
590 | if (i) |
591 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
592 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
593 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 594 | break; |
1da177e4 LT |
595 | } |
596 | i += sprintf(&buf[i], "\n"); | |
597 | return i; | |
598 | } | |
f4fd3797 | 599 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 600 | |
e8628dd0 DW |
601 | /** |
602 | * show_related_cpus - show the CPUs affected by each transition even if | |
603 | * hw coordination is in use | |
604 | */ | |
605 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
606 | { | |
f4fd3797 | 607 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
608 | } |
609 | ||
610 | /** | |
611 | * show_affected_cpus - show the CPUs affected by each transition | |
612 | */ | |
613 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
614 | { | |
f4fd3797 | 615 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
616 | } |
617 | ||
9e76988e | 618 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 619 | const char *buf, size_t count) |
9e76988e VP |
620 | { |
621 | unsigned int freq = 0; | |
622 | unsigned int ret; | |
623 | ||
879000f9 | 624 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
625 | return -EINVAL; |
626 | ||
627 | ret = sscanf(buf, "%u", &freq); | |
628 | if (ret != 1) | |
629 | return -EINVAL; | |
630 | ||
631 | policy->governor->store_setspeed(policy, freq); | |
632 | ||
633 | return count; | |
634 | } | |
635 | ||
636 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
637 | { | |
879000f9 | 638 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
639 | return sprintf(buf, "<unsupported>\n"); |
640 | ||
641 | return policy->governor->show_setspeed(policy, buf); | |
642 | } | |
1da177e4 | 643 | |
e2f74f35 | 644 | /** |
8bf1ac72 | 645 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
646 | */ |
647 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
648 | { | |
649 | unsigned int limit; | |
650 | int ret; | |
1c3d85dd RW |
651 | if (cpufreq_driver->bios_limit) { |
652 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
653 | if (!ret) |
654 | return sprintf(buf, "%u\n", limit); | |
655 | } | |
656 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
657 | } | |
658 | ||
6dad2a29 BP |
659 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
660 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
661 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
662 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
663 | cpufreq_freq_attr_ro(scaling_available_governors); | |
664 | cpufreq_freq_attr_ro(scaling_driver); | |
665 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
666 | cpufreq_freq_attr_ro(bios_limit); | |
667 | cpufreq_freq_attr_ro(related_cpus); | |
668 | cpufreq_freq_attr_ro(affected_cpus); | |
669 | cpufreq_freq_attr_rw(scaling_min_freq); | |
670 | cpufreq_freq_attr_rw(scaling_max_freq); | |
671 | cpufreq_freq_attr_rw(scaling_governor); | |
672 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 673 | |
905d77cd | 674 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
675 | &cpuinfo_min_freq.attr, |
676 | &cpuinfo_max_freq.attr, | |
ed129784 | 677 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
678 | &scaling_min_freq.attr, |
679 | &scaling_max_freq.attr, | |
680 | &affected_cpus.attr, | |
e8628dd0 | 681 | &related_cpus.attr, |
1da177e4 LT |
682 | &scaling_governor.attr, |
683 | &scaling_driver.attr, | |
684 | &scaling_available_governors.attr, | |
9e76988e | 685 | &scaling_setspeed.attr, |
1da177e4 LT |
686 | NULL |
687 | }; | |
688 | ||
29464f28 DJ |
689 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
690 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 691 | |
29464f28 | 692 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 693 | { |
905d77cd DJ |
694 | struct cpufreq_policy *policy = to_policy(kobj); |
695 | struct freq_attr *fattr = to_attr(attr); | |
0db4a8a9 | 696 | ssize_t ret = -EINVAL; |
a9144436 | 697 | policy = cpufreq_cpu_get_sysfs(policy->cpu); |
1da177e4 | 698 | if (!policy) |
0db4a8a9 | 699 | goto no_policy; |
5a01f2e8 VP |
700 | |
701 | if (lock_policy_rwsem_read(policy->cpu) < 0) | |
0db4a8a9 | 702 | goto fail; |
5a01f2e8 | 703 | |
e08f5f5b GS |
704 | if (fattr->show) |
705 | ret = fattr->show(policy, buf); | |
706 | else | |
707 | ret = -EIO; | |
708 | ||
5a01f2e8 | 709 | unlock_policy_rwsem_read(policy->cpu); |
0db4a8a9 | 710 | fail: |
a9144436 | 711 | cpufreq_cpu_put_sysfs(policy); |
0db4a8a9 | 712 | no_policy: |
1da177e4 LT |
713 | return ret; |
714 | } | |
715 | ||
905d77cd DJ |
716 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
717 | const char *buf, size_t count) | |
1da177e4 | 718 | { |
905d77cd DJ |
719 | struct cpufreq_policy *policy = to_policy(kobj); |
720 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 721 | ssize_t ret = -EINVAL; |
a9144436 | 722 | policy = cpufreq_cpu_get_sysfs(policy->cpu); |
1da177e4 | 723 | if (!policy) |
a07530b4 | 724 | goto no_policy; |
5a01f2e8 VP |
725 | |
726 | if (lock_policy_rwsem_write(policy->cpu) < 0) | |
a07530b4 | 727 | goto fail; |
5a01f2e8 | 728 | |
e08f5f5b GS |
729 | if (fattr->store) |
730 | ret = fattr->store(policy, buf, count); | |
731 | else | |
732 | ret = -EIO; | |
733 | ||
5a01f2e8 | 734 | unlock_policy_rwsem_write(policy->cpu); |
a07530b4 | 735 | fail: |
a9144436 | 736 | cpufreq_cpu_put_sysfs(policy); |
a07530b4 | 737 | no_policy: |
1da177e4 LT |
738 | return ret; |
739 | } | |
740 | ||
905d77cd | 741 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 742 | { |
905d77cd | 743 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 744 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
745 | complete(&policy->kobj_unregister); |
746 | } | |
747 | ||
52cf25d0 | 748 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
749 | .show = show, |
750 | .store = store, | |
751 | }; | |
752 | ||
753 | static struct kobj_type ktype_cpufreq = { | |
754 | .sysfs_ops = &sysfs_ops, | |
755 | .default_attrs = default_attrs, | |
756 | .release = cpufreq_sysfs_release, | |
757 | }; | |
758 | ||
2361be23 VK |
759 | struct kobject *cpufreq_global_kobject; |
760 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
761 | ||
762 | static int cpufreq_global_kobject_usage; | |
763 | ||
764 | int cpufreq_get_global_kobject(void) | |
765 | { | |
766 | if (!cpufreq_global_kobject_usage++) | |
767 | return kobject_add(cpufreq_global_kobject, | |
768 | &cpu_subsys.dev_root->kobj, "%s", "cpufreq"); | |
769 | ||
770 | return 0; | |
771 | } | |
772 | EXPORT_SYMBOL(cpufreq_get_global_kobject); | |
773 | ||
774 | void cpufreq_put_global_kobject(void) | |
775 | { | |
776 | if (!--cpufreq_global_kobject_usage) | |
777 | kobject_del(cpufreq_global_kobject); | |
778 | } | |
779 | EXPORT_SYMBOL(cpufreq_put_global_kobject); | |
780 | ||
781 | int cpufreq_sysfs_create_file(const struct attribute *attr) | |
782 | { | |
783 | int ret = cpufreq_get_global_kobject(); | |
784 | ||
785 | if (!ret) { | |
786 | ret = sysfs_create_file(cpufreq_global_kobject, attr); | |
787 | if (ret) | |
788 | cpufreq_put_global_kobject(); | |
789 | } | |
790 | ||
791 | return ret; | |
792 | } | |
793 | EXPORT_SYMBOL(cpufreq_sysfs_create_file); | |
794 | ||
795 | void cpufreq_sysfs_remove_file(const struct attribute *attr) | |
796 | { | |
797 | sysfs_remove_file(cpufreq_global_kobject, attr); | |
798 | cpufreq_put_global_kobject(); | |
799 | } | |
800 | EXPORT_SYMBOL(cpufreq_sysfs_remove_file); | |
801 | ||
19d6f7ec | 802 | /* symlink affected CPUs */ |
308b60e7 | 803 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
804 | { |
805 | unsigned int j; | |
806 | int ret = 0; | |
807 | ||
808 | for_each_cpu(j, policy->cpus) { | |
8a25a2fd | 809 | struct device *cpu_dev; |
19d6f7ec | 810 | |
308b60e7 | 811 | if (j == policy->cpu) |
19d6f7ec | 812 | continue; |
19d6f7ec | 813 | |
e8fdde10 | 814 | pr_debug("Adding link for CPU: %u\n", j); |
8a25a2fd KS |
815 | cpu_dev = get_cpu_device(j); |
816 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
19d6f7ec | 817 | "cpufreq"); |
71c3461e RW |
818 | if (ret) |
819 | break; | |
19d6f7ec DJ |
820 | } |
821 | return ret; | |
822 | } | |
823 | ||
308b60e7 | 824 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy, |
8a25a2fd | 825 | struct device *dev) |
909a694e DJ |
826 | { |
827 | struct freq_attr **drv_attr; | |
909a694e | 828 | int ret = 0; |
909a694e DJ |
829 | |
830 | /* prepare interface data */ | |
831 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, | |
8a25a2fd | 832 | &dev->kobj, "cpufreq"); |
909a694e DJ |
833 | if (ret) |
834 | return ret; | |
835 | ||
836 | /* set up files for this cpu device */ | |
1c3d85dd | 837 | drv_attr = cpufreq_driver->attr; |
909a694e DJ |
838 | while ((drv_attr) && (*drv_attr)) { |
839 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); | |
840 | if (ret) | |
1c3d85dd | 841 | goto err_out_kobj_put; |
909a694e DJ |
842 | drv_attr++; |
843 | } | |
1c3d85dd | 844 | if (cpufreq_driver->get) { |
909a694e DJ |
845 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
846 | if (ret) | |
1c3d85dd | 847 | goto err_out_kobj_put; |
909a694e | 848 | } |
1c3d85dd | 849 | if (cpufreq_driver->target) { |
909a694e DJ |
850 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); |
851 | if (ret) | |
1c3d85dd | 852 | goto err_out_kobj_put; |
909a694e | 853 | } |
1c3d85dd | 854 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
855 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
856 | if (ret) | |
1c3d85dd | 857 | goto err_out_kobj_put; |
e2f74f35 | 858 | } |
909a694e | 859 | |
308b60e7 | 860 | ret = cpufreq_add_dev_symlink(policy); |
ecf7e461 DJ |
861 | if (ret) |
862 | goto err_out_kobj_put; | |
863 | ||
e18f1682 SB |
864 | return ret; |
865 | ||
866 | err_out_kobj_put: | |
867 | kobject_put(&policy->kobj); | |
868 | wait_for_completion(&policy->kobj_unregister); | |
869 | return ret; | |
870 | } | |
871 | ||
872 | static void cpufreq_init_policy(struct cpufreq_policy *policy) | |
873 | { | |
874 | struct cpufreq_policy new_policy; | |
875 | int ret = 0; | |
876 | ||
d5b73cd8 | 877 | memcpy(&new_policy, policy, sizeof(*policy)); |
ecf7e461 DJ |
878 | /* assure that the starting sequence is run in __cpufreq_set_policy */ |
879 | policy->governor = NULL; | |
880 | ||
881 | /* set default policy */ | |
882 | ret = __cpufreq_set_policy(policy, &new_policy); | |
883 | policy->user_policy.policy = policy->policy; | |
884 | policy->user_policy.governor = policy->governor; | |
885 | ||
886 | if (ret) { | |
2d06d8c4 | 887 | pr_debug("setting policy failed\n"); |
1c3d85dd RW |
888 | if (cpufreq_driver->exit) |
889 | cpufreq_driver->exit(policy); | |
ecf7e461 | 890 | } |
909a694e DJ |
891 | } |
892 | ||
fcf80582 | 893 | #ifdef CONFIG_HOTPLUG_CPU |
d8d3b471 VK |
894 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, |
895 | unsigned int cpu, struct device *dev, | |
896 | bool frozen) | |
fcf80582 | 897 | { |
1c3d85dd | 898 | int ret = 0, has_target = !!cpufreq_driver->target; |
fcf80582 VK |
899 | unsigned long flags; |
900 | ||
820c6ca2 VK |
901 | if (has_target) |
902 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
fcf80582 | 903 | |
d8d3b471 | 904 | lock_policy_rwsem_write(policy->cpu); |
2eaa3e2d | 905 | |
0d1857a1 | 906 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 907 | |
fcf80582 | 908 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 909 | per_cpu(cpufreq_policy_cpu, cpu) = policy->cpu; |
fcf80582 | 910 | per_cpu(cpufreq_cpu_data, cpu) = policy; |
0d1857a1 | 911 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fcf80582 | 912 | |
d8d3b471 | 913 | unlock_policy_rwsem_write(policy->cpu); |
2eaa3e2d | 914 | |
820c6ca2 VK |
915 | if (has_target) { |
916 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
917 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
918 | } | |
fcf80582 | 919 | |
a82fab29 | 920 | /* Don't touch sysfs links during light-weight init */ |
71c3461e RW |
921 | if (!frozen) |
922 | ret = sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); | |
a82fab29 SB |
923 | |
924 | return ret; | |
fcf80582 VK |
925 | } |
926 | #endif | |
1da177e4 | 927 | |
8414809c SB |
928 | static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu) |
929 | { | |
930 | struct cpufreq_policy *policy; | |
931 | unsigned long flags; | |
932 | ||
933 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
934 | ||
935 | policy = per_cpu(cpufreq_cpu_data_fallback, cpu); | |
936 | ||
937 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
938 | ||
939 | return policy; | |
940 | } | |
941 | ||
e9698cc5 SB |
942 | static struct cpufreq_policy *cpufreq_policy_alloc(void) |
943 | { | |
944 | struct cpufreq_policy *policy; | |
945 | ||
946 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); | |
947 | if (!policy) | |
948 | return NULL; | |
949 | ||
950 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
951 | goto err_free_policy; | |
952 | ||
953 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
954 | goto err_free_cpumask; | |
955 | ||
c88a1f8b | 956 | INIT_LIST_HEAD(&policy->policy_list); |
e9698cc5 SB |
957 | return policy; |
958 | ||
959 | err_free_cpumask: | |
960 | free_cpumask_var(policy->cpus); | |
961 | err_free_policy: | |
962 | kfree(policy); | |
963 | ||
964 | return NULL; | |
965 | } | |
966 | ||
967 | static void cpufreq_policy_free(struct cpufreq_policy *policy) | |
968 | { | |
c88a1f8b LM |
969 | unsigned long flags; |
970 | ||
971 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
972 | list_del(&policy->policy_list); | |
973 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
974 | ||
e9698cc5 SB |
975 | free_cpumask_var(policy->related_cpus); |
976 | free_cpumask_var(policy->cpus); | |
977 | kfree(policy); | |
978 | } | |
979 | ||
a82fab29 SB |
980 | static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, |
981 | bool frozen) | |
1da177e4 | 982 | { |
fcf80582 | 983 | unsigned int j, cpu = dev->id; |
65922465 | 984 | int ret = -ENOMEM; |
1da177e4 | 985 | struct cpufreq_policy *policy; |
1da177e4 | 986 | unsigned long flags; |
90e41bac | 987 | #ifdef CONFIG_HOTPLUG_CPU |
eb608521 | 988 | struct cpufreq_policy *tpolicy; |
fcf80582 | 989 | struct cpufreq_governor *gov; |
90e41bac | 990 | #endif |
1da177e4 | 991 | |
c32b6b8e AR |
992 | if (cpu_is_offline(cpu)) |
993 | return 0; | |
994 | ||
2d06d8c4 | 995 | pr_debug("adding CPU %u\n", cpu); |
1da177e4 LT |
996 | |
997 | #ifdef CONFIG_SMP | |
998 | /* check whether a different CPU already registered this | |
999 | * CPU because it is in the same boat. */ | |
1000 | policy = cpufreq_cpu_get(cpu); | |
1001 | if (unlikely(policy)) { | |
8ff69732 | 1002 | cpufreq_cpu_put(policy); |
1da177e4 LT |
1003 | return 0; |
1004 | } | |
fcf80582 VK |
1005 | |
1006 | #ifdef CONFIG_HOTPLUG_CPU | |
1007 | /* Check if this cpu was hot-unplugged earlier and has siblings */ | |
0d1857a1 | 1008 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
eb608521 VK |
1009 | list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) { |
1010 | if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) { | |
0d1857a1 | 1011 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
eb608521 VK |
1012 | return cpufreq_add_policy_cpu(tpolicy, cpu, dev, |
1013 | frozen); | |
2eaa3e2d | 1014 | } |
fcf80582 | 1015 | } |
0d1857a1 | 1016 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fcf80582 | 1017 | #endif |
1da177e4 LT |
1018 | #endif |
1019 | ||
1c3d85dd | 1020 | if (!try_module_get(cpufreq_driver->owner)) { |
1da177e4 LT |
1021 | ret = -EINVAL; |
1022 | goto module_out; | |
1023 | } | |
1024 | ||
8414809c SB |
1025 | if (frozen) |
1026 | /* Restore the saved policy when doing light-weight init */ | |
1027 | policy = cpufreq_policy_restore(cpu); | |
1028 | else | |
1029 | policy = cpufreq_policy_alloc(); | |
1030 | ||
059019a3 | 1031 | if (!policy) |
1da177e4 | 1032 | goto nomem_out; |
059019a3 | 1033 | |
1da177e4 | 1034 | policy->cpu = cpu; |
65922465 | 1035 | policy->governor = CPUFREQ_DEFAULT_GOVERNOR; |
835481d9 | 1036 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1037 | |
5a01f2e8 | 1038 | /* Initially set CPU itself as the policy_cpu */ |
f1625066 | 1039 | per_cpu(cpufreq_policy_cpu, cpu) = cpu; |
5a01f2e8 | 1040 | |
1da177e4 | 1041 | init_completion(&policy->kobj_unregister); |
65f27f38 | 1042 | INIT_WORK(&policy->update, handle_update); |
1da177e4 LT |
1043 | |
1044 | /* call driver. From then on the cpufreq must be able | |
1045 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1046 | */ | |
1c3d85dd | 1047 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1048 | if (ret) { |
2d06d8c4 | 1049 | pr_debug("initialization failed\n"); |
2eaa3e2d | 1050 | goto err_set_policy_cpu; |
1da177e4 | 1051 | } |
643ae6e8 | 1052 | |
fcf80582 VK |
1053 | /* related cpus should atleast have policy->cpus */ |
1054 | cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); | |
1055 | ||
643ae6e8 VK |
1056 | /* |
1057 | * affected cpus must always be the one, which are online. We aren't | |
1058 | * managing offline cpus here. | |
1059 | */ | |
1060 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1061 | ||
187d9f4e MC |
1062 | policy->user_policy.min = policy->min; |
1063 | policy->user_policy.max = policy->max; | |
1da177e4 | 1064 | |
a1531acd TR |
1065 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1066 | CPUFREQ_START, policy); | |
1067 | ||
fcf80582 VK |
1068 | #ifdef CONFIG_HOTPLUG_CPU |
1069 | gov = __find_governor(per_cpu(cpufreq_cpu_governor, cpu)); | |
1070 | if (gov) { | |
1071 | policy->governor = gov; | |
1072 | pr_debug("Restoring governor %s for cpu %d\n", | |
1073 | policy->governor->name, cpu); | |
4bfa042c | 1074 | } |
fcf80582 | 1075 | #endif |
1da177e4 | 1076 | |
e18f1682 SB |
1077 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1078 | for_each_cpu(j, policy->cpus) { | |
1079 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1080 | per_cpu(cpufreq_policy_cpu, j) = policy->cpu; | |
1081 | } | |
1082 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1083 | ||
a82fab29 | 1084 | if (!frozen) { |
308b60e7 | 1085 | ret = cpufreq_add_dev_interface(policy, dev); |
a82fab29 SB |
1086 | if (ret) |
1087 | goto err_out_unregister; | |
c88a1f8b LM |
1088 | |
1089 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1090 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1091 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
a82fab29 | 1092 | } |
8ff69732 | 1093 | |
e18f1682 SB |
1094 | cpufreq_init_policy(policy); |
1095 | ||
038c5b3e | 1096 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
1c3d85dd | 1097 | module_put(cpufreq_driver->owner); |
2d06d8c4 | 1098 | pr_debug("initialization complete\n"); |
87c32271 | 1099 | |
1da177e4 LT |
1100 | return 0; |
1101 | ||
1da177e4 | 1102 | err_out_unregister: |
0d1857a1 | 1103 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
e18f1682 | 1104 | for_each_cpu(j, policy->cpus) { |
7a6aedfa | 1105 | per_cpu(cpufreq_cpu_data, j) = NULL; |
e18f1682 SB |
1106 | if (j != cpu) |
1107 | per_cpu(cpufreq_policy_cpu, j) = -1; | |
1108 | } | |
0d1857a1 | 1109 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1110 | |
2eaa3e2d VK |
1111 | err_set_policy_cpu: |
1112 | per_cpu(cpufreq_policy_cpu, cpu) = -1; | |
e9698cc5 | 1113 | cpufreq_policy_free(policy); |
1da177e4 | 1114 | nomem_out: |
1c3d85dd | 1115 | module_put(cpufreq_driver->owner); |
c32b6b8e | 1116 | module_out: |
1da177e4 LT |
1117 | return ret; |
1118 | } | |
1119 | ||
a82fab29 SB |
1120 | /** |
1121 | * cpufreq_add_dev - add a CPU device | |
1122 | * | |
1123 | * Adds the cpufreq interface for a CPU device. | |
1124 | * | |
1125 | * The Oracle says: try running cpufreq registration/unregistration concurrently | |
1126 | * with with cpu hotplugging and all hell will break loose. Tried to clean this | |
1127 | * mess up, but more thorough testing is needed. - Mathieu | |
1128 | */ | |
1129 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1130 | { | |
1131 | return __cpufreq_add_dev(dev, sif, false); | |
1132 | } | |
1133 | ||
b8eed8af VK |
1134 | static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
1135 | { | |
1136 | int j; | |
1137 | ||
1138 | policy->last_cpu = policy->cpu; | |
1139 | policy->cpu = cpu; | |
1140 | ||
3361b7b1 | 1141 | for_each_cpu(j, policy->cpus) |
b8eed8af | 1142 | per_cpu(cpufreq_policy_cpu, j) = cpu; |
b8eed8af VK |
1143 | |
1144 | #ifdef CONFIG_CPU_FREQ_TABLE | |
1145 | cpufreq_frequency_table_update_policy_cpu(policy); | |
1146 | #endif | |
1147 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1148 | CPUFREQ_UPDATE_POLICY_CPU, policy); | |
1149 | } | |
1da177e4 | 1150 | |
3a3e9e06 | 1151 | static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, |
a82fab29 | 1152 | unsigned int old_cpu, bool frozen) |
f9ba680d SB |
1153 | { |
1154 | struct device *cpu_dev; | |
1155 | unsigned long flags; | |
1156 | int ret; | |
1157 | ||
1158 | /* first sibling now owns the new sysfs dir */ | |
3a3e9e06 | 1159 | cpu_dev = get_cpu_device(cpumask_first(policy->cpus)); |
a82fab29 SB |
1160 | |
1161 | /* Don't touch sysfs files during light-weight tear-down */ | |
1162 | if (frozen) | |
1163 | return cpu_dev->id; | |
1164 | ||
f9ba680d | 1165 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); |
3a3e9e06 | 1166 | ret = kobject_move(&policy->kobj, &cpu_dev->kobj); |
f9ba680d SB |
1167 | if (ret) { |
1168 | pr_err("%s: Failed to move kobj: %d", __func__, ret); | |
1169 | ||
1170 | WARN_ON(lock_policy_rwsem_write(old_cpu)); | |
3a3e9e06 | 1171 | cpumask_set_cpu(old_cpu, policy->cpus); |
f9ba680d SB |
1172 | |
1173 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
3a3e9e06 | 1174 | per_cpu(cpufreq_cpu_data, old_cpu) = policy; |
f9ba680d SB |
1175 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1176 | ||
1177 | unlock_policy_rwsem_write(old_cpu); | |
1178 | ||
3a3e9e06 | 1179 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, |
f9ba680d SB |
1180 | "cpufreq"); |
1181 | ||
1182 | return -EINVAL; | |
1183 | } | |
1184 | ||
1185 | return cpu_dev->id; | |
1186 | } | |
1187 | ||
1da177e4 | 1188 | /** |
5a01f2e8 | 1189 | * __cpufreq_remove_dev - remove a CPU device |
1da177e4 LT |
1190 | * |
1191 | * Removes the cpufreq interface for a CPU device. | |
5a01f2e8 VP |
1192 | * Caller should already have policy_rwsem in write mode for this CPU. |
1193 | * This routine frees the rwsem before returning. | |
1da177e4 | 1194 | */ |
bb176f7d | 1195 | static int __cpufreq_remove_dev(struct device *dev, |
a82fab29 | 1196 | struct subsys_interface *sif, bool frozen) |
1da177e4 | 1197 | { |
f9ba680d SB |
1198 | unsigned int cpu = dev->id, cpus; |
1199 | int new_cpu; | |
1da177e4 | 1200 | unsigned long flags; |
3a3e9e06 | 1201 | struct cpufreq_policy *policy; |
499bca9b AW |
1202 | struct kobject *kobj; |
1203 | struct completion *cmp; | |
1da177e4 | 1204 | |
b8eed8af | 1205 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1206 | |
0d1857a1 | 1207 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 1208 | |
3a3e9e06 | 1209 | policy = per_cpu(cpufreq_cpu_data, cpu); |
2eaa3e2d VK |
1210 | per_cpu(cpufreq_cpu_data, cpu) = NULL; |
1211 | ||
8414809c SB |
1212 | /* Save the policy somewhere when doing a light-weight tear-down */ |
1213 | if (frozen) | |
3a3e9e06 | 1214 | per_cpu(cpufreq_cpu_data_fallback, cpu) = policy; |
8414809c | 1215 | |
0d1857a1 | 1216 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1217 | |
3a3e9e06 | 1218 | if (!policy) { |
b8eed8af | 1219 | pr_debug("%s: No cpu_data found\n", __func__); |
1da177e4 LT |
1220 | return -EINVAL; |
1221 | } | |
1da177e4 | 1222 | |
1c3d85dd | 1223 | if (cpufreq_driver->target) |
3a3e9e06 | 1224 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1da177e4 | 1225 | |
084f3493 | 1226 | #ifdef CONFIG_HOTPLUG_CPU |
1c3d85dd | 1227 | if (!cpufreq_driver->setpolicy) |
fa69e33f | 1228 | strncpy(per_cpu(cpufreq_cpu_governor, cpu), |
3a3e9e06 | 1229 | policy->governor->name, CPUFREQ_NAME_LEN); |
1da177e4 LT |
1230 | #endif |
1231 | ||
2eaa3e2d | 1232 | WARN_ON(lock_policy_rwsem_write(cpu)); |
3a3e9e06 | 1233 | cpus = cpumask_weight(policy->cpus); |
e4969eba VK |
1234 | |
1235 | if (cpus > 1) | |
3a3e9e06 | 1236 | cpumask_clear_cpu(cpu, policy->cpus); |
2eaa3e2d | 1237 | unlock_policy_rwsem_write(cpu); |
084f3493 | 1238 | |
3a3e9e06 | 1239 | if (cpu != policy->cpu && !frozen) { |
73bf0fc2 VK |
1240 | sysfs_remove_link(&dev->kobj, "cpufreq"); |
1241 | } else if (cpus > 1) { | |
084f3493 | 1242 | |
3a3e9e06 | 1243 | new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu, frozen); |
f9ba680d | 1244 | if (new_cpu >= 0) { |
2eaa3e2d | 1245 | WARN_ON(lock_policy_rwsem_write(cpu)); |
3a3e9e06 | 1246 | update_policy_cpu(policy, new_cpu); |
499bca9b | 1247 | unlock_policy_rwsem_write(cpu); |
a82fab29 SB |
1248 | |
1249 | if (!frozen) { | |
1250 | pr_debug("%s: policy Kobject moved to cpu: %d " | |
1251 | "from: %d\n",__func__, new_cpu, cpu); | |
1252 | } | |
1da177e4 LT |
1253 | } |
1254 | } | |
1da177e4 | 1255 | |
b8eed8af VK |
1256 | /* If cpu is last user of policy, free policy */ |
1257 | if (cpus == 1) { | |
2a998599 | 1258 | if (cpufreq_driver->target) |
3a3e9e06 | 1259 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
2a998599 | 1260 | |
8414809c SB |
1261 | if (!frozen) { |
1262 | lock_policy_rwsem_read(cpu); | |
3a3e9e06 VK |
1263 | kobj = &policy->kobj; |
1264 | cmp = &policy->kobj_unregister; | |
8414809c SB |
1265 | unlock_policy_rwsem_read(cpu); |
1266 | kobject_put(kobj); | |
1267 | ||
1268 | /* | |
1269 | * We need to make sure that the underlying kobj is | |
1270 | * actually not referenced anymore by anybody before we | |
1271 | * proceed with unloading. | |
1272 | */ | |
1273 | pr_debug("waiting for dropping of refcount\n"); | |
1274 | wait_for_completion(cmp); | |
1275 | pr_debug("wait complete\n"); | |
1276 | } | |
7d26e2d5 | 1277 | |
8414809c SB |
1278 | /* |
1279 | * Perform the ->exit() even during light-weight tear-down, | |
1280 | * since this is a core component, and is essential for the | |
1281 | * subsequent light-weight ->init() to succeed. | |
b8eed8af | 1282 | */ |
1c3d85dd | 1283 | if (cpufreq_driver->exit) |
3a3e9e06 | 1284 | cpufreq_driver->exit(policy); |
27ecddc2 | 1285 | |
8414809c | 1286 | if (!frozen) |
3a3e9e06 | 1287 | cpufreq_policy_free(policy); |
2a998599 | 1288 | } else { |
2a998599 | 1289 | if (cpufreq_driver->target) { |
3a3e9e06 VK |
1290 | __cpufreq_governor(policy, CPUFREQ_GOV_START); |
1291 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2a998599 | 1292 | } |
27ecddc2 | 1293 | } |
1da177e4 | 1294 | |
2eaa3e2d | 1295 | per_cpu(cpufreq_policy_cpu, cpu) = -1; |
1da177e4 LT |
1296 | return 0; |
1297 | } | |
1298 | ||
8a25a2fd | 1299 | static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1300 | { |
8a25a2fd | 1301 | unsigned int cpu = dev->id; |
5a01f2e8 | 1302 | int retval; |
ec28297a VP |
1303 | |
1304 | if (cpu_is_offline(cpu)) | |
1305 | return 0; | |
1306 | ||
a82fab29 | 1307 | retval = __cpufreq_remove_dev(dev, sif, false); |
5a01f2e8 VP |
1308 | return retval; |
1309 | } | |
1310 | ||
65f27f38 | 1311 | static void handle_update(struct work_struct *work) |
1da177e4 | 1312 | { |
65f27f38 DH |
1313 | struct cpufreq_policy *policy = |
1314 | container_of(work, struct cpufreq_policy, update); | |
1315 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1316 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1317 | cpufreq_update_policy(cpu); |
1318 | } | |
1319 | ||
1320 | /** | |
bb176f7d VK |
1321 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1322 | * in deep trouble. | |
1da177e4 LT |
1323 | * @cpu: cpu number |
1324 | * @old_freq: CPU frequency the kernel thinks the CPU runs at | |
1325 | * @new_freq: CPU frequency the CPU actually runs at | |
1326 | * | |
29464f28 DJ |
1327 | * We adjust to current frequency first, and need to clean up later. |
1328 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1329 | */ |
e08f5f5b GS |
1330 | static void cpufreq_out_of_sync(unsigned int cpu, unsigned int old_freq, |
1331 | unsigned int new_freq) | |
1da177e4 | 1332 | { |
b43a7ffb | 1333 | struct cpufreq_policy *policy; |
1da177e4 | 1334 | struct cpufreq_freqs freqs; |
b43a7ffb VK |
1335 | unsigned long flags; |
1336 | ||
2d06d8c4 | 1337 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing " |
1da177e4 LT |
1338 | "core thinks of %u, is %u kHz.\n", old_freq, new_freq); |
1339 | ||
1da177e4 LT |
1340 | freqs.old = old_freq; |
1341 | freqs.new = new_freq; | |
b43a7ffb VK |
1342 | |
1343 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1344 | policy = per_cpu(cpufreq_cpu_data, cpu); | |
1345 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1346 | ||
1347 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); | |
1348 | cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); | |
1da177e4 LT |
1349 | } |
1350 | ||
32ee8c3e | 1351 | /** |
4ab70df4 | 1352 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1353 | * @cpu: CPU number |
1354 | * | |
1355 | * This is the last known freq, without actually getting it from the driver. | |
1356 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1357 | */ | |
1358 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1359 | { | |
9e21ba8b | 1360 | struct cpufreq_policy *policy; |
e08f5f5b | 1361 | unsigned int ret_freq = 0; |
95235ca2 | 1362 | |
1c3d85dd RW |
1363 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1364 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1365 | |
1366 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1367 | if (policy) { |
e08f5f5b | 1368 | ret_freq = policy->cur; |
95235ca2 VP |
1369 | cpufreq_cpu_put(policy); |
1370 | } | |
1371 | ||
4d34a67d | 1372 | return ret_freq; |
95235ca2 VP |
1373 | } |
1374 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1375 | ||
3d737108 JB |
1376 | /** |
1377 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1378 | * @cpu: CPU number | |
1379 | * | |
1380 | * Just return the max possible frequency for a given CPU. | |
1381 | */ | |
1382 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1383 | { | |
1384 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1385 | unsigned int ret_freq = 0; | |
1386 | ||
1387 | if (policy) { | |
1388 | ret_freq = policy->max; | |
1389 | cpufreq_cpu_put(policy); | |
1390 | } | |
1391 | ||
1392 | return ret_freq; | |
1393 | } | |
1394 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1395 | ||
5a01f2e8 | 1396 | static unsigned int __cpufreq_get(unsigned int cpu) |
1da177e4 | 1397 | { |
7a6aedfa | 1398 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
e08f5f5b | 1399 | unsigned int ret_freq = 0; |
5800043b | 1400 | |
1c3d85dd | 1401 | if (!cpufreq_driver->get) |
4d34a67d | 1402 | return ret_freq; |
1da177e4 | 1403 | |
1c3d85dd | 1404 | ret_freq = cpufreq_driver->get(cpu); |
1da177e4 | 1405 | |
e08f5f5b | 1406 | if (ret_freq && policy->cur && |
1c3d85dd | 1407 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1408 | /* verify no discrepancy between actual and |
1409 | saved value exists */ | |
1410 | if (unlikely(ret_freq != policy->cur)) { | |
1411 | cpufreq_out_of_sync(cpu, policy->cur, ret_freq); | |
1da177e4 LT |
1412 | schedule_work(&policy->update); |
1413 | } | |
1414 | } | |
1415 | ||
4d34a67d | 1416 | return ret_freq; |
5a01f2e8 | 1417 | } |
1da177e4 | 1418 | |
5a01f2e8 VP |
1419 | /** |
1420 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1421 | * @cpu: CPU number | |
1422 | * | |
1423 | * Get the CPU current (static) CPU frequency | |
1424 | */ | |
1425 | unsigned int cpufreq_get(unsigned int cpu) | |
1426 | { | |
1427 | unsigned int ret_freq = 0; | |
1428 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1429 | ||
1430 | if (!policy) | |
1431 | goto out; | |
1432 | ||
1433 | if (unlikely(lock_policy_rwsem_read(cpu))) | |
1434 | goto out_policy; | |
1435 | ||
1436 | ret_freq = __cpufreq_get(cpu); | |
1437 | ||
1438 | unlock_policy_rwsem_read(cpu); | |
1da177e4 | 1439 | |
5a01f2e8 VP |
1440 | out_policy: |
1441 | cpufreq_cpu_put(policy); | |
1442 | out: | |
4d34a67d | 1443 | return ret_freq; |
1da177e4 LT |
1444 | } |
1445 | EXPORT_SYMBOL(cpufreq_get); | |
1446 | ||
8a25a2fd KS |
1447 | static struct subsys_interface cpufreq_interface = { |
1448 | .name = "cpufreq", | |
1449 | .subsys = &cpu_subsys, | |
1450 | .add_dev = cpufreq_add_dev, | |
1451 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1452 | }; |
1453 | ||
42d4dc3f | 1454 | /** |
e00e56df RW |
1455 | * cpufreq_bp_suspend - Prepare the boot CPU for system suspend. |
1456 | * | |
1457 | * This function is only executed for the boot processor. The other CPUs | |
1458 | * have been put offline by means of CPU hotplug. | |
42d4dc3f | 1459 | */ |
e00e56df | 1460 | static int cpufreq_bp_suspend(void) |
42d4dc3f | 1461 | { |
e08f5f5b | 1462 | int ret = 0; |
4bc5d341 | 1463 | |
e00e56df | 1464 | int cpu = smp_processor_id(); |
3a3e9e06 | 1465 | struct cpufreq_policy *policy; |
42d4dc3f | 1466 | |
2d06d8c4 | 1467 | pr_debug("suspending cpu %u\n", cpu); |
42d4dc3f | 1468 | |
e00e56df | 1469 | /* If there's no policy for the boot CPU, we have nothing to do. */ |
3a3e9e06 VK |
1470 | policy = cpufreq_cpu_get(cpu); |
1471 | if (!policy) | |
e00e56df | 1472 | return 0; |
42d4dc3f | 1473 | |
1c3d85dd | 1474 | if (cpufreq_driver->suspend) { |
3a3e9e06 | 1475 | ret = cpufreq_driver->suspend(policy); |
ce6c3997 | 1476 | if (ret) |
42d4dc3f | 1477 | printk(KERN_ERR "cpufreq: suspend failed in ->suspend " |
3a3e9e06 | 1478 | "step on CPU %u\n", policy->cpu); |
42d4dc3f BH |
1479 | } |
1480 | ||
3a3e9e06 | 1481 | cpufreq_cpu_put(policy); |
c9060494 | 1482 | return ret; |
42d4dc3f BH |
1483 | } |
1484 | ||
1da177e4 | 1485 | /** |
e00e56df | 1486 | * cpufreq_bp_resume - Restore proper frequency handling of the boot CPU. |
1da177e4 LT |
1487 | * |
1488 | * 1.) resume CPUfreq hardware support (cpufreq_driver->resume()) | |
ce6c3997 DB |
1489 | * 2.) schedule call cpufreq_update_policy() ASAP as interrupts are |
1490 | * restored. It will verify that the current freq is in sync with | |
1491 | * what we believe it to be. This is a bit later than when it | |
1492 | * should be, but nonethteless it's better than calling | |
1493 | * cpufreq_driver->get() here which might re-enable interrupts... | |
e00e56df RW |
1494 | * |
1495 | * This function is only executed for the boot CPU. The other CPUs have not | |
1496 | * been turned on yet. | |
1da177e4 | 1497 | */ |
e00e56df | 1498 | static void cpufreq_bp_resume(void) |
1da177e4 | 1499 | { |
e08f5f5b | 1500 | int ret = 0; |
4bc5d341 | 1501 | |
e00e56df | 1502 | int cpu = smp_processor_id(); |
3a3e9e06 | 1503 | struct cpufreq_policy *policy; |
1da177e4 | 1504 | |
2d06d8c4 | 1505 | pr_debug("resuming cpu %u\n", cpu); |
1da177e4 | 1506 | |
e00e56df | 1507 | /* If there's no policy for the boot CPU, we have nothing to do. */ |
3a3e9e06 VK |
1508 | policy = cpufreq_cpu_get(cpu); |
1509 | if (!policy) | |
e00e56df | 1510 | return; |
1da177e4 | 1511 | |
1c3d85dd | 1512 | if (cpufreq_driver->resume) { |
3a3e9e06 | 1513 | ret = cpufreq_driver->resume(policy); |
1da177e4 LT |
1514 | if (ret) { |
1515 | printk(KERN_ERR "cpufreq: resume failed in ->resume " | |
3a3e9e06 | 1516 | "step on CPU %u\n", policy->cpu); |
c9060494 | 1517 | goto fail; |
1da177e4 LT |
1518 | } |
1519 | } | |
1520 | ||
3a3e9e06 | 1521 | schedule_work(&policy->update); |
ce6c3997 | 1522 | |
c9060494 | 1523 | fail: |
3a3e9e06 | 1524 | cpufreq_cpu_put(policy); |
1da177e4 LT |
1525 | } |
1526 | ||
e00e56df RW |
1527 | static struct syscore_ops cpufreq_syscore_ops = { |
1528 | .suspend = cpufreq_bp_suspend, | |
1529 | .resume = cpufreq_bp_resume, | |
1da177e4 LT |
1530 | }; |
1531 | ||
9d95046e BP |
1532 | /** |
1533 | * cpufreq_get_current_driver - return current driver's name | |
1534 | * | |
1535 | * Return the name string of the currently loaded cpufreq driver | |
1536 | * or NULL, if none. | |
1537 | */ | |
1538 | const char *cpufreq_get_current_driver(void) | |
1539 | { | |
1c3d85dd RW |
1540 | if (cpufreq_driver) |
1541 | return cpufreq_driver->name; | |
1542 | ||
1543 | return NULL; | |
9d95046e BP |
1544 | } |
1545 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 LT |
1546 | |
1547 | /********************************************************************* | |
1548 | * NOTIFIER LISTS INTERFACE * | |
1549 | *********************************************************************/ | |
1550 | ||
1551 | /** | |
1552 | * cpufreq_register_notifier - register a driver with cpufreq | |
1553 | * @nb: notifier function to register | |
1554 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1555 | * | |
32ee8c3e | 1556 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1557 | * are notified about clock rate changes (once before and once after |
1558 | * the transition), or a list of drivers that are notified about | |
1559 | * changes in cpufreq policy. | |
1560 | * | |
1561 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1562 | * blocking_notifier_chain_register. |
1da177e4 LT |
1563 | */ |
1564 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1565 | { | |
1566 | int ret; | |
1567 | ||
d5aaffa9 DB |
1568 | if (cpufreq_disabled()) |
1569 | return -EINVAL; | |
1570 | ||
74212ca4 CEB |
1571 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1572 | ||
1da177e4 LT |
1573 | switch (list) { |
1574 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1575 | ret = srcu_notifier_chain_register( |
e041c683 | 1576 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1577 | break; |
1578 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1579 | ret = blocking_notifier_chain_register( |
1580 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1581 | break; |
1582 | default: | |
1583 | ret = -EINVAL; | |
1584 | } | |
1da177e4 LT |
1585 | |
1586 | return ret; | |
1587 | } | |
1588 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1589 | ||
1da177e4 LT |
1590 | /** |
1591 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1592 | * @nb: notifier block to be unregistered | |
bb176f7d | 1593 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1594 | * |
1595 | * Remove a driver from the CPU frequency notifier list. | |
1596 | * | |
1597 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1598 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1599 | */ |
1600 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1601 | { | |
1602 | int ret; | |
1603 | ||
d5aaffa9 DB |
1604 | if (cpufreq_disabled()) |
1605 | return -EINVAL; | |
1606 | ||
1da177e4 LT |
1607 | switch (list) { |
1608 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1609 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1610 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1611 | break; |
1612 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1613 | ret = blocking_notifier_chain_unregister( |
1614 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1615 | break; |
1616 | default: | |
1617 | ret = -EINVAL; | |
1618 | } | |
1da177e4 LT |
1619 | |
1620 | return ret; | |
1621 | } | |
1622 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1623 | ||
1624 | ||
1625 | /********************************************************************* | |
1626 | * GOVERNORS * | |
1627 | *********************************************************************/ | |
1628 | ||
1da177e4 LT |
1629 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1630 | unsigned int target_freq, | |
1631 | unsigned int relation) | |
1632 | { | |
1633 | int retval = -EINVAL; | |
7249924e | 1634 | unsigned int old_target_freq = target_freq; |
c32b6b8e | 1635 | |
a7b422cd KRW |
1636 | if (cpufreq_disabled()) |
1637 | return -ENODEV; | |
7c30ed53 VK |
1638 | if (policy->transition_ongoing) |
1639 | return -EBUSY; | |
a7b422cd | 1640 | |
7249924e VK |
1641 | /* Make sure that target_freq is within supported range */ |
1642 | if (target_freq > policy->max) | |
1643 | target_freq = policy->max; | |
1644 | if (target_freq < policy->min) | |
1645 | target_freq = policy->min; | |
1646 | ||
1647 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
1648 | policy->cpu, target_freq, relation, old_target_freq); | |
5a1c0228 VK |
1649 | |
1650 | if (target_freq == policy->cur) | |
1651 | return 0; | |
1652 | ||
1c3d85dd RW |
1653 | if (cpufreq_driver->target) |
1654 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
90d45d17 | 1655 | |
1da177e4 LT |
1656 | return retval; |
1657 | } | |
1658 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1659 | ||
1da177e4 LT |
1660 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1661 | unsigned int target_freq, | |
1662 | unsigned int relation) | |
1663 | { | |
f1829e4a | 1664 | int ret = -EINVAL; |
1da177e4 | 1665 | |
5a01f2e8 | 1666 | if (unlikely(lock_policy_rwsem_write(policy->cpu))) |
f1829e4a | 1667 | goto fail; |
1da177e4 LT |
1668 | |
1669 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1670 | ||
5a01f2e8 | 1671 | unlock_policy_rwsem_write(policy->cpu); |
1da177e4 | 1672 | |
f1829e4a | 1673 | fail: |
1da177e4 LT |
1674 | return ret; |
1675 | } | |
1676 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1677 | ||
153d7f3f | 1678 | /* |
153d7f3f AV |
1679 | * when "event" is CPUFREQ_GOV_LIMITS |
1680 | */ | |
1da177e4 | 1681 | |
e08f5f5b GS |
1682 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
1683 | unsigned int event) | |
1da177e4 | 1684 | { |
cc993cab | 1685 | int ret; |
6afde10c TR |
1686 | |
1687 | /* Only must be defined when default governor is known to have latency | |
1688 | restrictions, like e.g. conservative or ondemand. | |
1689 | That this is the case is already ensured in Kconfig | |
1690 | */ | |
1691 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
1692 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
1693 | #else | |
1694 | struct cpufreq_governor *gov = NULL; | |
1695 | #endif | |
1c256245 TR |
1696 | |
1697 | if (policy->governor->max_transition_latency && | |
1698 | policy->cpuinfo.transition_latency > | |
1699 | policy->governor->max_transition_latency) { | |
6afde10c TR |
1700 | if (!gov) |
1701 | return -EINVAL; | |
1702 | else { | |
1703 | printk(KERN_WARNING "%s governor failed, too long" | |
1704 | " transition latency of HW, fallback" | |
1705 | " to %s governor\n", | |
1706 | policy->governor->name, | |
1707 | gov->name); | |
1708 | policy->governor = gov; | |
1709 | } | |
1c256245 | 1710 | } |
1da177e4 | 1711 | |
fe492f3f VK |
1712 | if (event == CPUFREQ_GOV_POLICY_INIT) |
1713 | if (!try_module_get(policy->governor->owner)) | |
1714 | return -EINVAL; | |
1da177e4 | 1715 | |
2d06d8c4 | 1716 | pr_debug("__cpufreq_governor for CPU %u, event %u\n", |
e08f5f5b | 1717 | policy->cpu, event); |
95731ebb XC |
1718 | |
1719 | mutex_lock(&cpufreq_governor_lock); | |
1720 | if ((!policy->governor_enabled && (event == CPUFREQ_GOV_STOP)) || | |
1721 | (policy->governor_enabled && (event == CPUFREQ_GOV_START))) { | |
1722 | mutex_unlock(&cpufreq_governor_lock); | |
fe492f3f VK |
1723 | if (event == CPUFREQ_GOV_POLICY_INIT) |
1724 | module_put(policy->governor->owner); | |
95731ebb XC |
1725 | return -EBUSY; |
1726 | } | |
1727 | ||
1728 | if (event == CPUFREQ_GOV_STOP) | |
1729 | policy->governor_enabled = false; | |
1730 | else if (event == CPUFREQ_GOV_START) | |
1731 | policy->governor_enabled = true; | |
1732 | ||
1733 | mutex_unlock(&cpufreq_governor_lock); | |
1734 | ||
1da177e4 LT |
1735 | ret = policy->governor->governor(policy, event); |
1736 | ||
4d5dcc42 VK |
1737 | if (!ret) { |
1738 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
1739 | policy->governor->initialized++; | |
1740 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
1741 | policy->governor->initialized--; | |
95731ebb XC |
1742 | } else { |
1743 | /* Restore original values */ | |
1744 | mutex_lock(&cpufreq_governor_lock); | |
1745 | if (event == CPUFREQ_GOV_STOP) | |
1746 | policy->governor_enabled = true; | |
1747 | else if (event == CPUFREQ_GOV_START) | |
1748 | policy->governor_enabled = false; | |
1749 | mutex_unlock(&cpufreq_governor_lock); | |
4d5dcc42 | 1750 | } |
b394058f | 1751 | |
fe492f3f VK |
1752 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
1753 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
1754 | module_put(policy->governor->owner); |
1755 | ||
1756 | return ret; | |
1757 | } | |
1758 | ||
1da177e4 LT |
1759 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
1760 | { | |
3bcb09a3 | 1761 | int err; |
1da177e4 LT |
1762 | |
1763 | if (!governor) | |
1764 | return -EINVAL; | |
1765 | ||
a7b422cd KRW |
1766 | if (cpufreq_disabled()) |
1767 | return -ENODEV; | |
1768 | ||
3fc54d37 | 1769 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 1770 | |
b394058f | 1771 | governor->initialized = 0; |
3bcb09a3 JF |
1772 | err = -EBUSY; |
1773 | if (__find_governor(governor->name) == NULL) { | |
1774 | err = 0; | |
1775 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 1776 | } |
1da177e4 | 1777 | |
32ee8c3e | 1778 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 1779 | return err; |
1da177e4 LT |
1780 | } |
1781 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
1782 | ||
1da177e4 LT |
1783 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
1784 | { | |
90e41bac PB |
1785 | #ifdef CONFIG_HOTPLUG_CPU |
1786 | int cpu; | |
1787 | #endif | |
1788 | ||
1da177e4 LT |
1789 | if (!governor) |
1790 | return; | |
1791 | ||
a7b422cd KRW |
1792 | if (cpufreq_disabled()) |
1793 | return; | |
1794 | ||
90e41bac PB |
1795 | #ifdef CONFIG_HOTPLUG_CPU |
1796 | for_each_present_cpu(cpu) { | |
1797 | if (cpu_online(cpu)) | |
1798 | continue; | |
1799 | if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name)) | |
1800 | strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0"); | |
1801 | } | |
1802 | #endif | |
1803 | ||
3fc54d37 | 1804 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 1805 | list_del(&governor->governor_list); |
3fc54d37 | 1806 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
1807 | return; |
1808 | } | |
1809 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
1810 | ||
1811 | ||
1da177e4 LT |
1812 | /********************************************************************* |
1813 | * POLICY INTERFACE * | |
1814 | *********************************************************************/ | |
1815 | ||
1816 | /** | |
1817 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
1818 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
1819 | * is written | |
1da177e4 LT |
1820 | * |
1821 | * Reads the current cpufreq policy. | |
1822 | */ | |
1823 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
1824 | { | |
1825 | struct cpufreq_policy *cpu_policy; | |
1826 | if (!policy) | |
1827 | return -EINVAL; | |
1828 | ||
1829 | cpu_policy = cpufreq_cpu_get(cpu); | |
1830 | if (!cpu_policy) | |
1831 | return -EINVAL; | |
1832 | ||
d5b73cd8 | 1833 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
1834 | |
1835 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
1836 | return 0; |
1837 | } | |
1838 | EXPORT_SYMBOL(cpufreq_get_policy); | |
1839 | ||
153d7f3f | 1840 | /* |
e08f5f5b GS |
1841 | * data : current policy. |
1842 | * policy : policy to be set. | |
153d7f3f | 1843 | */ |
3a3e9e06 VK |
1844 | static int __cpufreq_set_policy(struct cpufreq_policy *policy, |
1845 | struct cpufreq_policy *new_policy) | |
1da177e4 | 1846 | { |
7bd353a9 | 1847 | int ret = 0, failed = 1; |
1da177e4 | 1848 | |
3a3e9e06 VK |
1849 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", new_policy->cpu, |
1850 | new_policy->min, new_policy->max); | |
1da177e4 | 1851 | |
d5b73cd8 | 1852 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 1853 | |
3a3e9e06 | 1854 | if (new_policy->min > policy->max || new_policy->max < policy->min) { |
9c9a43ed MD |
1855 | ret = -EINVAL; |
1856 | goto error_out; | |
1857 | } | |
1858 | ||
1da177e4 | 1859 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 1860 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 LT |
1861 | if (ret) |
1862 | goto error_out; | |
1863 | ||
1da177e4 | 1864 | /* adjust if necessary - all reasons */ |
e041c683 | 1865 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 1866 | CPUFREQ_ADJUST, new_policy); |
1da177e4 LT |
1867 | |
1868 | /* adjust if necessary - hardware incompatibility*/ | |
e041c683 | 1869 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 1870 | CPUFREQ_INCOMPATIBLE, new_policy); |
1da177e4 | 1871 | |
bb176f7d VK |
1872 | /* |
1873 | * verify the cpu speed can be set within this limit, which might be | |
1874 | * different to the first one | |
1875 | */ | |
3a3e9e06 | 1876 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 1877 | if (ret) |
1da177e4 | 1878 | goto error_out; |
1da177e4 LT |
1879 | |
1880 | /* notification of the new policy */ | |
e041c683 | 1881 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 1882 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 1883 | |
3a3e9e06 VK |
1884 | policy->min = new_policy->min; |
1885 | policy->max = new_policy->max; | |
1da177e4 | 1886 | |
2d06d8c4 | 1887 | pr_debug("new min and max freqs are %u - %u kHz\n", |
3a3e9e06 | 1888 | policy->min, policy->max); |
1da177e4 | 1889 | |
1c3d85dd | 1890 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 1891 | policy->policy = new_policy->policy; |
2d06d8c4 | 1892 | pr_debug("setting range\n"); |
3a3e9e06 | 1893 | ret = cpufreq_driver->setpolicy(new_policy); |
1da177e4 | 1894 | } else { |
3a3e9e06 | 1895 | if (new_policy->governor != policy->governor) { |
1da177e4 | 1896 | /* save old, working values */ |
3a3e9e06 | 1897 | struct cpufreq_governor *old_gov = policy->governor; |
1da177e4 | 1898 | |
2d06d8c4 | 1899 | pr_debug("governor switch\n"); |
1da177e4 LT |
1900 | |
1901 | /* end old governor */ | |
3a3e9e06 VK |
1902 | if (policy->governor) { |
1903 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
1904 | unlock_policy_rwsem_write(new_policy->cpu); | |
1905 | __cpufreq_governor(policy, | |
7bd353a9 | 1906 | CPUFREQ_GOV_POLICY_EXIT); |
3a3e9e06 | 1907 | lock_policy_rwsem_write(new_policy->cpu); |
7bd353a9 | 1908 | } |
1da177e4 LT |
1909 | |
1910 | /* start new governor */ | |
3a3e9e06 VK |
1911 | policy->governor = new_policy->governor; |
1912 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) { | |
1913 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_START)) { | |
7bd353a9 | 1914 | failed = 0; |
955ef483 | 1915 | } else { |
3a3e9e06 VK |
1916 | unlock_policy_rwsem_write(new_policy->cpu); |
1917 | __cpufreq_governor(policy, | |
7bd353a9 | 1918 | CPUFREQ_GOV_POLICY_EXIT); |
3a3e9e06 | 1919 | lock_policy_rwsem_write(new_policy->cpu); |
955ef483 | 1920 | } |
7bd353a9 VK |
1921 | } |
1922 | ||
1923 | if (failed) { | |
1da177e4 | 1924 | /* new governor failed, so re-start old one */ |
2d06d8c4 | 1925 | pr_debug("starting governor %s failed\n", |
3a3e9e06 | 1926 | policy->governor->name); |
1da177e4 | 1927 | if (old_gov) { |
3a3e9e06 VK |
1928 | policy->governor = old_gov; |
1929 | __cpufreq_governor(policy, | |
7bd353a9 | 1930 | CPUFREQ_GOV_POLICY_INIT); |
3a3e9e06 | 1931 | __cpufreq_governor(policy, |
e08f5f5b | 1932 | CPUFREQ_GOV_START); |
1da177e4 LT |
1933 | } |
1934 | ret = -EINVAL; | |
1935 | goto error_out; | |
1936 | } | |
1937 | /* might be a policy change, too, so fall through */ | |
1938 | } | |
2d06d8c4 | 1939 | pr_debug("governor: change or update limits\n"); |
3a3e9e06 | 1940 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
1da177e4 LT |
1941 | } |
1942 | ||
7d5e350f | 1943 | error_out: |
1da177e4 LT |
1944 | return ret; |
1945 | } | |
1946 | ||
1da177e4 LT |
1947 | /** |
1948 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
1949 | * @cpu: CPU which shall be re-evaluated | |
1950 | * | |
25985edc | 1951 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
1952 | * at different times. |
1953 | */ | |
1954 | int cpufreq_update_policy(unsigned int cpu) | |
1955 | { | |
3a3e9e06 VK |
1956 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
1957 | struct cpufreq_policy new_policy; | |
f1829e4a | 1958 | int ret; |
1da177e4 | 1959 | |
3a3e9e06 | 1960 | if (!policy) { |
f1829e4a JL |
1961 | ret = -ENODEV; |
1962 | goto no_policy; | |
1963 | } | |
1da177e4 | 1964 | |
f1829e4a JL |
1965 | if (unlikely(lock_policy_rwsem_write(cpu))) { |
1966 | ret = -EINVAL; | |
1967 | goto fail; | |
1968 | } | |
1da177e4 | 1969 | |
2d06d8c4 | 1970 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 1971 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
1972 | new_policy.min = policy->user_policy.min; |
1973 | new_policy.max = policy->user_policy.max; | |
1974 | new_policy.policy = policy->user_policy.policy; | |
1975 | new_policy.governor = policy->user_policy.governor; | |
1da177e4 | 1976 | |
bb176f7d VK |
1977 | /* |
1978 | * BIOS might change freq behind our back | |
1979 | * -> ask driver for current freq and notify governors about a change | |
1980 | */ | |
1c3d85dd | 1981 | if (cpufreq_driver->get) { |
3a3e9e06 VK |
1982 | new_policy.cur = cpufreq_driver->get(cpu); |
1983 | if (!policy->cur) { | |
2d06d8c4 | 1984 | pr_debug("Driver did not initialize current freq"); |
3a3e9e06 | 1985 | policy->cur = new_policy.cur; |
a85f7bd3 | 1986 | } else { |
3a3e9e06 VK |
1987 | if (policy->cur != new_policy.cur && cpufreq_driver->target) |
1988 | cpufreq_out_of_sync(cpu, policy->cur, | |
1989 | new_policy.cur); | |
a85f7bd3 | 1990 | } |
0961dd0d TR |
1991 | } |
1992 | ||
3a3e9e06 | 1993 | ret = __cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 1994 | |
5a01f2e8 VP |
1995 | unlock_policy_rwsem_write(cpu); |
1996 | ||
f1829e4a | 1997 | fail: |
3a3e9e06 | 1998 | cpufreq_cpu_put(policy); |
f1829e4a | 1999 | no_policy: |
1da177e4 LT |
2000 | return ret; |
2001 | } | |
2002 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2003 | ||
2760984f | 2004 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2005 | unsigned long action, void *hcpu) |
2006 | { | |
2007 | unsigned int cpu = (unsigned long)hcpu; | |
8a25a2fd | 2008 | struct device *dev; |
5302c3fb | 2009 | bool frozen = false; |
c32b6b8e | 2010 | |
8a25a2fd KS |
2011 | dev = get_cpu_device(cpu); |
2012 | if (dev) { | |
5302c3fb SB |
2013 | |
2014 | if (action & CPU_TASKS_FROZEN) | |
2015 | frozen = true; | |
2016 | ||
2017 | switch (action & ~CPU_TASKS_FROZEN) { | |
c32b6b8e | 2018 | case CPU_ONLINE: |
5302c3fb | 2019 | __cpufreq_add_dev(dev, NULL, frozen); |
23d32899 | 2020 | cpufreq_update_policy(cpu); |
c32b6b8e | 2021 | break; |
5302c3fb | 2022 | |
c32b6b8e | 2023 | case CPU_DOWN_PREPARE: |
5302c3fb | 2024 | __cpufreq_remove_dev(dev, NULL, frozen); |
c32b6b8e | 2025 | break; |
5302c3fb | 2026 | |
5a01f2e8 | 2027 | case CPU_DOWN_FAILED: |
5302c3fb | 2028 | __cpufreq_add_dev(dev, NULL, frozen); |
c32b6b8e AR |
2029 | break; |
2030 | } | |
2031 | } | |
2032 | return NOTIFY_OK; | |
2033 | } | |
2034 | ||
9c36f746 | 2035 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2036 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2037 | }; |
1da177e4 LT |
2038 | |
2039 | /********************************************************************* | |
2040 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2041 | *********************************************************************/ | |
2042 | ||
2043 | /** | |
2044 | * cpufreq_register_driver - register a CPU Frequency driver | |
2045 | * @driver_data: A struct cpufreq_driver containing the values# | |
2046 | * submitted by the CPU Frequency driver. | |
2047 | * | |
bb176f7d | 2048 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 2049 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 2050 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2051 | * |
2052 | */ | |
221dee28 | 2053 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2054 | { |
2055 | unsigned long flags; | |
2056 | int ret; | |
2057 | ||
a7b422cd KRW |
2058 | if (cpufreq_disabled()) |
2059 | return -ENODEV; | |
2060 | ||
1da177e4 LT |
2061 | if (!driver_data || !driver_data->verify || !driver_data->init || |
2062 | ((!driver_data->setpolicy) && (!driver_data->target))) | |
2063 | return -EINVAL; | |
2064 | ||
2d06d8c4 | 2065 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 LT |
2066 | |
2067 | if (driver_data->setpolicy) | |
2068 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2069 | ||
0d1857a1 | 2070 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2071 | if (cpufreq_driver) { |
0d1857a1 | 2072 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
2073 | return -EBUSY; |
2074 | } | |
1c3d85dd | 2075 | cpufreq_driver = driver_data; |
0d1857a1 | 2076 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2077 | |
8a25a2fd | 2078 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab JS |
2079 | if (ret) |
2080 | goto err_null_driver; | |
1da177e4 | 2081 | |
1c3d85dd | 2082 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) { |
1da177e4 LT |
2083 | int i; |
2084 | ret = -ENODEV; | |
2085 | ||
2086 | /* check for at least one working CPU */ | |
7a6aedfa MT |
2087 | for (i = 0; i < nr_cpu_ids; i++) |
2088 | if (cpu_possible(i) && per_cpu(cpufreq_cpu_data, i)) { | |
1da177e4 | 2089 | ret = 0; |
7a6aedfa MT |
2090 | break; |
2091 | } | |
1da177e4 LT |
2092 | |
2093 | /* if all ->init() calls failed, unregister */ | |
2094 | if (ret) { | |
2d06d8c4 | 2095 | pr_debug("no CPU initialized for driver %s\n", |
e08f5f5b | 2096 | driver_data->name); |
8a25a2fd | 2097 | goto err_if_unreg; |
1da177e4 LT |
2098 | } |
2099 | } | |
2100 | ||
8f5bc2ab | 2101 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2102 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2103 | |
8f5bc2ab | 2104 | return 0; |
8a25a2fd KS |
2105 | err_if_unreg: |
2106 | subsys_interface_unregister(&cpufreq_interface); | |
8f5bc2ab | 2107 | err_null_driver: |
0d1857a1 | 2108 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2109 | cpufreq_driver = NULL; |
0d1857a1 | 2110 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4d34a67d | 2111 | return ret; |
1da177e4 LT |
2112 | } |
2113 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2114 | ||
1da177e4 LT |
2115 | /** |
2116 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2117 | * | |
bb176f7d | 2118 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2119 | * the right to do so, i.e. if you have succeeded in initialising before! |
2120 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2121 | * currently not initialised. | |
2122 | */ | |
221dee28 | 2123 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2124 | { |
2125 | unsigned long flags; | |
2126 | ||
1c3d85dd | 2127 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2128 | return -EINVAL; |
1da177e4 | 2129 | |
2d06d8c4 | 2130 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2131 | |
8a25a2fd | 2132 | subsys_interface_unregister(&cpufreq_interface); |
65edc68c | 2133 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2134 | |
0d1857a1 | 2135 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2136 | cpufreq_driver = NULL; |
0d1857a1 | 2137 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 LT |
2138 | |
2139 | return 0; | |
2140 | } | |
2141 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 VP |
2142 | |
2143 | static int __init cpufreq_core_init(void) | |
2144 | { | |
2145 | int cpu; | |
2146 | ||
a7b422cd KRW |
2147 | if (cpufreq_disabled()) |
2148 | return -ENODEV; | |
2149 | ||
5a01f2e8 | 2150 | for_each_possible_cpu(cpu) { |
f1625066 | 2151 | per_cpu(cpufreq_policy_cpu, cpu) = -1; |
5a01f2e8 VP |
2152 | init_rwsem(&per_cpu(cpu_policy_rwsem, cpu)); |
2153 | } | |
8aa84ad8 | 2154 | |
2361be23 | 2155 | cpufreq_global_kobject = kobject_create(); |
8aa84ad8 | 2156 | BUG_ON(!cpufreq_global_kobject); |
e00e56df | 2157 | register_syscore_ops(&cpufreq_syscore_ops); |
8aa84ad8 | 2158 | |
5a01f2e8 VP |
2159 | return 0; |
2160 | } | |
5a01f2e8 | 2161 | core_initcall(cpufreq_core_init); |