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Commit | Line | Data |
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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> |
2f0aea93 | 29 | #include <linux/suspend.h> |
90de2a4a | 30 | #include <linux/syscore_ops.h> |
5ff0a268 | 31 | #include <linux/tick.h> |
6f4f2723 TR |
32 | #include <trace/events/power.h> |
33 | ||
b4f0676f | 34 | static LIST_HEAD(cpufreq_policy_list); |
f963735a VK |
35 | |
36 | static inline bool policy_is_inactive(struct cpufreq_policy *policy) | |
37 | { | |
38 | return cpumask_empty(policy->cpus); | |
39 | } | |
40 | ||
41 | static bool suitable_policy(struct cpufreq_policy *policy, bool active) | |
42 | { | |
43 | return active == !policy_is_inactive(policy); | |
44 | } | |
45 | ||
46 | /* Finds Next Acive/Inactive policy */ | |
47 | static struct cpufreq_policy *next_policy(struct cpufreq_policy *policy, | |
48 | bool active) | |
49 | { | |
50 | do { | |
51 | policy = list_next_entry(policy, policy_list); | |
52 | ||
53 | /* No more policies in the list */ | |
54 | if (&policy->policy_list == &cpufreq_policy_list) | |
55 | return NULL; | |
56 | } while (!suitable_policy(policy, active)); | |
57 | ||
58 | return policy; | |
59 | } | |
60 | ||
61 | static struct cpufreq_policy *first_policy(bool active) | |
62 | { | |
63 | struct cpufreq_policy *policy; | |
64 | ||
65 | /* No policies in the list */ | |
66 | if (list_empty(&cpufreq_policy_list)) | |
67 | return NULL; | |
68 | ||
69 | policy = list_first_entry(&cpufreq_policy_list, typeof(*policy), | |
70 | policy_list); | |
71 | ||
72 | if (!suitable_policy(policy, active)) | |
73 | policy = next_policy(policy, active); | |
74 | ||
75 | return policy; | |
76 | } | |
77 | ||
78 | /* Macros to iterate over CPU policies */ | |
79 | #define for_each_suitable_policy(__policy, __active) \ | |
80 | for (__policy = first_policy(__active); \ | |
81 | __policy; \ | |
82 | __policy = next_policy(__policy, __active)) | |
83 | ||
84 | #define for_each_active_policy(__policy) \ | |
85 | for_each_suitable_policy(__policy, true) | |
86 | #define for_each_inactive_policy(__policy) \ | |
87 | for_each_suitable_policy(__policy, false) | |
88 | ||
89 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
90 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
91 | ||
f7b27061 VK |
92 | /* Iterate over governors */ |
93 | static LIST_HEAD(cpufreq_governor_list); | |
94 | #define for_each_governor(__governor) \ | |
95 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
96 | ||
1da177e4 | 97 | /** |
cd878479 | 98 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
99 | * level driver of CPUFreq support, and its spinlock. This lock |
100 | * also protects the cpufreq_cpu_data array. | |
101 | */ | |
1c3d85dd | 102 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 103 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 104 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
6f1e4efd | 105 | DEFINE_MUTEX(cpufreq_governor_lock); |
bb176f7d | 106 | |
2f0aea93 VK |
107 | /* Flag to suspend/resume CPUFreq governors */ |
108 | static bool cpufreq_suspended; | |
1da177e4 | 109 | |
9c0ebcf7 VK |
110 | static inline bool has_target(void) |
111 | { | |
112 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
113 | } | |
114 | ||
6eed9404 VK |
115 | /* |
116 | * rwsem to guarantee that cpufreq driver module doesn't unload during critical | |
117 | * sections | |
118 | */ | |
119 | static DECLARE_RWSEM(cpufreq_rwsem); | |
120 | ||
1da177e4 | 121 | /* internal prototypes */ |
29464f28 DJ |
122 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
123 | unsigned int event); | |
d92d50a4 | 124 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
65f27f38 | 125 | static void handle_update(struct work_struct *work); |
1da177e4 LT |
126 | |
127 | /** | |
32ee8c3e DJ |
128 | * Two notifier lists: the "policy" list is involved in the |
129 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
130 | * "transition" list for kernel code that needs to handle |
131 | * changes to devices when the CPU clock speed changes. | |
132 | * The mutex locks both lists. | |
133 | */ | |
e041c683 | 134 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 135 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 136 | |
74212ca4 | 137 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
138 | static int __init init_cpufreq_transition_notifier_list(void) |
139 | { | |
140 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 141 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
142 | return 0; |
143 | } | |
b3438f82 | 144 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 145 | |
a7b422cd | 146 | static int off __read_mostly; |
da584455 | 147 | static int cpufreq_disabled(void) |
a7b422cd KRW |
148 | { |
149 | return off; | |
150 | } | |
151 | void disable_cpufreq(void) | |
152 | { | |
153 | off = 1; | |
154 | } | |
29464f28 | 155 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 156 | |
4d5dcc42 VK |
157 | bool have_governor_per_policy(void) |
158 | { | |
0b981e70 | 159 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 160 | } |
3f869d6d | 161 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 162 | |
944e9a03 VK |
163 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
164 | { | |
165 | if (have_governor_per_policy()) | |
166 | return &policy->kobj; | |
167 | else | |
168 | return cpufreq_global_kobject; | |
169 | } | |
170 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
171 | ||
5a31d594 VK |
172 | struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu) |
173 | { | |
174 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
175 | ||
176 | return policy && !policy_is_inactive(policy) ? | |
177 | policy->freq_table : NULL; | |
178 | } | |
179 | EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table); | |
180 | ||
72a4ce34 VK |
181 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
182 | { | |
183 | u64 idle_time; | |
184 | u64 cur_wall_time; | |
185 | u64 busy_time; | |
186 | ||
187 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
188 | ||
189 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
190 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
191 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
192 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
193 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
194 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
195 | ||
196 | idle_time = cur_wall_time - busy_time; | |
197 | if (wall) | |
198 | *wall = cputime_to_usecs(cur_wall_time); | |
199 | ||
200 | return cputime_to_usecs(idle_time); | |
201 | } | |
202 | ||
203 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
204 | { | |
205 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
206 | ||
207 | if (idle_time == -1ULL) | |
208 | return get_cpu_idle_time_jiffy(cpu, wall); | |
209 | else if (!io_busy) | |
210 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
211 | ||
212 | return idle_time; | |
213 | } | |
214 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
215 | ||
70e9e778 VK |
216 | /* |
217 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
218 | * drivers of SMP systems. It will do following: | |
219 | * - validate & show freq table passed | |
220 | * - set policies transition latency | |
221 | * - policy->cpus with all possible CPUs | |
222 | */ | |
223 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
224 | struct cpufreq_frequency_table *table, | |
225 | unsigned int transition_latency) | |
226 | { | |
227 | int ret; | |
228 | ||
229 | ret = cpufreq_table_validate_and_show(policy, table); | |
230 | if (ret) { | |
231 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
232 | return ret; | |
233 | } | |
234 | ||
235 | policy->cpuinfo.transition_latency = transition_latency; | |
236 | ||
237 | /* | |
58405af6 | 238 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
239 | * share the clock and voltage and clock. |
240 | */ | |
241 | cpumask_setall(policy->cpus); | |
242 | ||
243 | return 0; | |
244 | } | |
245 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
246 | ||
988bed09 VK |
247 | /* Only for cpufreq core internal use */ |
248 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) | |
652ed95d VK |
249 | { |
250 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
251 | ||
988bed09 VK |
252 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
253 | } | |
254 | ||
255 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
256 | { | |
257 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
258 | ||
652ed95d | 259 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
260 | pr_err("%s: No %s associated to cpu: %d\n", |
261 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
262 | return 0; |
263 | } | |
264 | ||
265 | return clk_get_rate(policy->clk) / 1000; | |
266 | } | |
267 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
268 | ||
50e9c852 VK |
269 | /** |
270 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
271 | * | |
272 | * @cpu: cpu to find policy for. | |
273 | * | |
274 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
275 | * It also increments the kobject reference count to mark it busy and so would | |
276 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
277 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
278 | * freed as that depends on the kobj count. | |
279 | * | |
280 | * It also takes a read-lock of 'cpufreq_rwsem' and doesn't put it back if a | |
281 | * valid policy is found. This is done to make sure the driver doesn't get | |
282 | * unregistered while the policy is being used. | |
283 | * | |
284 | * Return: A valid policy on success, otherwise NULL on failure. | |
285 | */ | |
6eed9404 | 286 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 287 | { |
6eed9404 | 288 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
289 | unsigned long flags; |
290 | ||
1b947c90 | 291 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
292 | return NULL; |
293 | ||
294 | if (!down_read_trylock(&cpufreq_rwsem)) | |
295 | return NULL; | |
1da177e4 LT |
296 | |
297 | /* get the cpufreq driver */ | |
1c3d85dd | 298 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 299 | |
6eed9404 VK |
300 | if (cpufreq_driver) { |
301 | /* get the CPU */ | |
988bed09 | 302 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
303 | if (policy) |
304 | kobject_get(&policy->kobj); | |
305 | } | |
1da177e4 | 306 | |
6eed9404 | 307 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 308 | |
3a3e9e06 | 309 | if (!policy) |
6eed9404 | 310 | up_read(&cpufreq_rwsem); |
1da177e4 | 311 | |
3a3e9e06 | 312 | return policy; |
a9144436 | 313 | } |
1da177e4 LT |
314 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
315 | ||
50e9c852 VK |
316 | /** |
317 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
318 | * | |
319 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
320 | * | |
321 | * This decrements the kobject reference count incremented earlier by calling | |
322 | * cpufreq_cpu_get(). | |
323 | * | |
324 | * It also drops the read-lock of 'cpufreq_rwsem' taken at cpufreq_cpu_get(). | |
325 | */ | |
3a3e9e06 | 326 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 327 | { |
6eed9404 VK |
328 | kobject_put(&policy->kobj); |
329 | up_read(&cpufreq_rwsem); | |
1da177e4 LT |
330 | } |
331 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
332 | ||
1da177e4 LT |
333 | /********************************************************************* |
334 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
335 | *********************************************************************/ | |
336 | ||
337 | /** | |
338 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
339 | * | |
340 | * This function alters the system "loops_per_jiffy" for the clock | |
341 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 342 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
343 | * per-CPU loops_per_jiffy value wherever possible. |
344 | */ | |
858119e1 | 345 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 346 | { |
39c132ee VK |
347 | #ifndef CONFIG_SMP |
348 | static unsigned long l_p_j_ref; | |
349 | static unsigned int l_p_j_ref_freq; | |
350 | ||
1da177e4 LT |
351 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
352 | return; | |
353 | ||
354 | if (!l_p_j_ref_freq) { | |
355 | l_p_j_ref = loops_per_jiffy; | |
356 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
357 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
358 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 359 | } |
0b443ead | 360 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
361 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
362 | ci->new); | |
e837f9b5 JP |
363 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
364 | loops_per_jiffy, ci->new); | |
1da177e4 | 365 | } |
1da177e4 | 366 | #endif |
39c132ee | 367 | } |
1da177e4 | 368 | |
0956df9c | 369 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 370 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
371 | { |
372 | BUG_ON(irqs_disabled()); | |
373 | ||
d5aaffa9 DB |
374 | if (cpufreq_disabled()) |
375 | return; | |
376 | ||
1c3d85dd | 377 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 378 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 379 | state, freqs->new); |
1da177e4 | 380 | |
1da177e4 | 381 | switch (state) { |
e4472cb3 | 382 | |
1da177e4 | 383 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 384 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
385 | * which is not equal to what the cpufreq core thinks is |
386 | * "old frequency". | |
1da177e4 | 387 | */ |
1c3d85dd | 388 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
389 | if ((policy) && (policy->cpu == freqs->cpu) && |
390 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
391 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
392 | freqs->old, policy->cur); | |
e4472cb3 | 393 | freqs->old = policy->cur; |
1da177e4 LT |
394 | } |
395 | } | |
b4dfdbb3 | 396 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 397 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
398 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
399 | break; | |
e4472cb3 | 400 | |
1da177e4 LT |
401 | case CPUFREQ_POSTCHANGE: |
402 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
403 | pr_debug("FREQ: %lu - CPU: %lu\n", |
404 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 405 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 406 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 407 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
408 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
409 | policy->cur = freqs->new; | |
1da177e4 LT |
410 | break; |
411 | } | |
1da177e4 | 412 | } |
bb176f7d | 413 | |
b43a7ffb VK |
414 | /** |
415 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
416 | * on frequency transition. | |
417 | * | |
418 | * This function calls the transition notifiers and the "adjust_jiffies" | |
419 | * function. It is called twice on all CPU frequency changes that have | |
420 | * external effects. | |
421 | */ | |
236a9800 | 422 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
423 | struct cpufreq_freqs *freqs, unsigned int state) |
424 | { | |
425 | for_each_cpu(freqs->cpu, policy->cpus) | |
426 | __cpufreq_notify_transition(policy, freqs, state); | |
427 | } | |
1da177e4 | 428 | |
f7ba3b41 | 429 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 430 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
431 | struct cpufreq_freqs *freqs, int transition_failed) |
432 | { | |
433 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
434 | if (!transition_failed) | |
435 | return; | |
436 | ||
437 | swap(freqs->old, freqs->new); | |
438 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
439 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
440 | } | |
f7ba3b41 | 441 | |
12478cf0 SB |
442 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
443 | struct cpufreq_freqs *freqs) | |
444 | { | |
ca654dc3 SB |
445 | |
446 | /* | |
447 | * Catch double invocations of _begin() which lead to self-deadlock. | |
448 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
449 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
450 | * double invocations are very low. Moreover, there are scenarios | |
451 | * where these checks can emit false-positive warnings in these | |
452 | * drivers; so we avoid that by skipping them altogether. | |
453 | */ | |
454 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
455 | && current == policy->transition_task); | |
456 | ||
12478cf0 SB |
457 | wait: |
458 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
459 | ||
460 | spin_lock(&policy->transition_lock); | |
461 | ||
462 | if (unlikely(policy->transition_ongoing)) { | |
463 | spin_unlock(&policy->transition_lock); | |
464 | goto wait; | |
465 | } | |
466 | ||
467 | policy->transition_ongoing = true; | |
ca654dc3 | 468 | policy->transition_task = current; |
12478cf0 SB |
469 | |
470 | spin_unlock(&policy->transition_lock); | |
471 | ||
472 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
473 | } | |
474 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
475 | ||
476 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
477 | struct cpufreq_freqs *freqs, int transition_failed) | |
478 | { | |
479 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
480 | return; | |
481 | ||
482 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
483 | ||
484 | policy->transition_ongoing = false; | |
ca654dc3 | 485 | policy->transition_task = NULL; |
12478cf0 SB |
486 | |
487 | wake_up(&policy->transition_wait); | |
488 | } | |
489 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
490 | ||
1da177e4 | 491 | |
1da177e4 LT |
492 | /********************************************************************* |
493 | * SYSFS INTERFACE * | |
494 | *********************************************************************/ | |
8a5c74a1 | 495 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
496 | struct attribute *attr, char *buf) |
497 | { | |
498 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
499 | } | |
500 | ||
501 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
502 | const char *buf, size_t count) | |
503 | { | |
504 | int ret, enable; | |
505 | ||
506 | ret = sscanf(buf, "%d", &enable); | |
507 | if (ret != 1 || enable < 0 || enable > 1) | |
508 | return -EINVAL; | |
509 | ||
510 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
511 | pr_err("%s: Cannot %s BOOST!\n", |
512 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
513 | return -EINVAL; |
514 | } | |
515 | ||
e837f9b5 JP |
516 | pr_debug("%s: cpufreq BOOST %s\n", |
517 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
518 | |
519 | return count; | |
520 | } | |
521 | define_one_global_rw(boost); | |
1da177e4 | 522 | |
42f91fa1 | 523 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
524 | { |
525 | struct cpufreq_governor *t; | |
526 | ||
f7b27061 | 527 | for_each_governor(t) |
7c4f4539 | 528 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
529 | return t; |
530 | ||
531 | return NULL; | |
532 | } | |
533 | ||
1da177e4 LT |
534 | /** |
535 | * cpufreq_parse_governor - parse a governor string | |
536 | */ | |
905d77cd | 537 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
538 | struct cpufreq_governor **governor) |
539 | { | |
3bcb09a3 | 540 | int err = -EINVAL; |
1c3d85dd RW |
541 | |
542 | if (!cpufreq_driver) | |
3bcb09a3 JF |
543 | goto out; |
544 | ||
1c3d85dd | 545 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 546 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 547 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 548 | err = 0; |
7c4f4539 | 549 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 550 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 551 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 552 | err = 0; |
1da177e4 | 553 | } |
2e1cc3a5 | 554 | } else { |
1da177e4 | 555 | struct cpufreq_governor *t; |
3bcb09a3 | 556 | |
3fc54d37 | 557 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 558 | |
42f91fa1 | 559 | t = find_governor(str_governor); |
3bcb09a3 | 560 | |
ea714970 | 561 | if (t == NULL) { |
1a8e1463 | 562 | int ret; |
ea714970 | 563 | |
1a8e1463 KC |
564 | mutex_unlock(&cpufreq_governor_mutex); |
565 | ret = request_module("cpufreq_%s", str_governor); | |
566 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 567 | |
1a8e1463 | 568 | if (ret == 0) |
42f91fa1 | 569 | t = find_governor(str_governor); |
ea714970 JF |
570 | } |
571 | ||
3bcb09a3 JF |
572 | if (t != NULL) { |
573 | *governor = t; | |
574 | err = 0; | |
1da177e4 | 575 | } |
3bcb09a3 | 576 | |
3fc54d37 | 577 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 578 | } |
29464f28 | 579 | out: |
3bcb09a3 | 580 | return err; |
1da177e4 | 581 | } |
1da177e4 | 582 | |
1da177e4 | 583 | /** |
e08f5f5b GS |
584 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
585 | * print out cpufreq information | |
1da177e4 LT |
586 | * |
587 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
588 | * "unsigned int". | |
589 | */ | |
590 | ||
32ee8c3e DJ |
591 | #define show_one(file_name, object) \ |
592 | static ssize_t show_##file_name \ | |
905d77cd | 593 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 594 | { \ |
29464f28 | 595 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
596 | } |
597 | ||
598 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
599 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 600 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
601 | show_one(scaling_min_freq, min); |
602 | show_one(scaling_max_freq, max); | |
c034b02e | 603 | |
09347b29 | 604 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
605 | { |
606 | ssize_t ret; | |
607 | ||
608 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
609 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
610 | else | |
611 | ret = sprintf(buf, "%u\n", policy->cur); | |
612 | return ret; | |
613 | } | |
1da177e4 | 614 | |
037ce839 | 615 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 616 | struct cpufreq_policy *new_policy); |
7970e08b | 617 | |
1da177e4 LT |
618 | /** |
619 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
620 | */ | |
621 | #define store_one(file_name, object) \ | |
622 | static ssize_t store_##file_name \ | |
905d77cd | 623 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 624 | { \ |
619c144c | 625 | int ret, temp; \ |
1da177e4 LT |
626 | struct cpufreq_policy new_policy; \ |
627 | \ | |
628 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ | |
629 | if (ret) \ | |
630 | return -EINVAL; \ | |
631 | \ | |
29464f28 | 632 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
633 | if (ret != 1) \ |
634 | return -EINVAL; \ | |
635 | \ | |
619c144c | 636 | temp = new_policy.object; \ |
037ce839 | 637 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
638 | if (!ret) \ |
639 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
640 | \ |
641 | return ret ? ret : count; \ | |
642 | } | |
643 | ||
29464f28 DJ |
644 | store_one(scaling_min_freq, min); |
645 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
646 | |
647 | /** | |
648 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
649 | */ | |
905d77cd DJ |
650 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
651 | char *buf) | |
1da177e4 | 652 | { |
d92d50a4 | 653 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
654 | if (!cur_freq) |
655 | return sprintf(buf, "<unknown>"); | |
656 | return sprintf(buf, "%u\n", cur_freq); | |
657 | } | |
658 | ||
1da177e4 LT |
659 | /** |
660 | * show_scaling_governor - show the current policy for the specified CPU | |
661 | */ | |
905d77cd | 662 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 663 | { |
29464f28 | 664 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
665 | return sprintf(buf, "powersave\n"); |
666 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
667 | return sprintf(buf, "performance\n"); | |
668 | else if (policy->governor) | |
4b972f0b | 669 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 670 | policy->governor->name); |
1da177e4 LT |
671 | return -EINVAL; |
672 | } | |
673 | ||
1da177e4 LT |
674 | /** |
675 | * store_scaling_governor - store policy for the specified CPU | |
676 | */ | |
905d77cd DJ |
677 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
678 | const char *buf, size_t count) | |
1da177e4 | 679 | { |
5136fa56 | 680 | int ret; |
1da177e4 LT |
681 | char str_governor[16]; |
682 | struct cpufreq_policy new_policy; | |
683 | ||
684 | ret = cpufreq_get_policy(&new_policy, policy->cpu); | |
685 | if (ret) | |
686 | return ret; | |
687 | ||
29464f28 | 688 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
689 | if (ret != 1) |
690 | return -EINVAL; | |
691 | ||
e08f5f5b GS |
692 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
693 | &new_policy.governor)) | |
1da177e4 LT |
694 | return -EINVAL; |
695 | ||
037ce839 | 696 | ret = cpufreq_set_policy(policy, &new_policy); |
7970e08b TR |
697 | |
698 | policy->user_policy.policy = policy->policy; | |
699 | policy->user_policy.governor = policy->governor; | |
7970e08b | 700 | |
e08f5f5b GS |
701 | if (ret) |
702 | return ret; | |
703 | else | |
704 | return count; | |
1da177e4 LT |
705 | } |
706 | ||
707 | /** | |
708 | * show_scaling_driver - show the cpufreq driver currently loaded | |
709 | */ | |
905d77cd | 710 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 711 | { |
1c3d85dd | 712 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
713 | } |
714 | ||
715 | /** | |
716 | * show_scaling_available_governors - show the available CPUfreq governors | |
717 | */ | |
905d77cd DJ |
718 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
719 | char *buf) | |
1da177e4 LT |
720 | { |
721 | ssize_t i = 0; | |
722 | struct cpufreq_governor *t; | |
723 | ||
9c0ebcf7 | 724 | if (!has_target()) { |
1da177e4 LT |
725 | i += sprintf(buf, "performance powersave"); |
726 | goto out; | |
727 | } | |
728 | ||
f7b27061 | 729 | for_each_governor(t) { |
29464f28 DJ |
730 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
731 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 732 | goto out; |
4b972f0b | 733 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 734 | } |
7d5e350f | 735 | out: |
1da177e4 LT |
736 | i += sprintf(&buf[i], "\n"); |
737 | return i; | |
738 | } | |
e8628dd0 | 739 | |
f4fd3797 | 740 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
741 | { |
742 | ssize_t i = 0; | |
743 | unsigned int cpu; | |
744 | ||
835481d9 | 745 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
746 | if (i) |
747 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
748 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
749 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 750 | break; |
1da177e4 LT |
751 | } |
752 | i += sprintf(&buf[i], "\n"); | |
753 | return i; | |
754 | } | |
f4fd3797 | 755 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 756 | |
e8628dd0 DW |
757 | /** |
758 | * show_related_cpus - show the CPUs affected by each transition even if | |
759 | * hw coordination is in use | |
760 | */ | |
761 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
762 | { | |
f4fd3797 | 763 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
764 | } |
765 | ||
766 | /** | |
767 | * show_affected_cpus - show the CPUs affected by each transition | |
768 | */ | |
769 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
770 | { | |
f4fd3797 | 771 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
772 | } |
773 | ||
9e76988e | 774 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 775 | const char *buf, size_t count) |
9e76988e VP |
776 | { |
777 | unsigned int freq = 0; | |
778 | unsigned int ret; | |
779 | ||
879000f9 | 780 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
781 | return -EINVAL; |
782 | ||
783 | ret = sscanf(buf, "%u", &freq); | |
784 | if (ret != 1) | |
785 | return -EINVAL; | |
786 | ||
787 | policy->governor->store_setspeed(policy, freq); | |
788 | ||
789 | return count; | |
790 | } | |
791 | ||
792 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
793 | { | |
879000f9 | 794 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
795 | return sprintf(buf, "<unsupported>\n"); |
796 | ||
797 | return policy->governor->show_setspeed(policy, buf); | |
798 | } | |
1da177e4 | 799 | |
e2f74f35 | 800 | /** |
8bf1ac72 | 801 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
802 | */ |
803 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
804 | { | |
805 | unsigned int limit; | |
806 | int ret; | |
1c3d85dd RW |
807 | if (cpufreq_driver->bios_limit) { |
808 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
809 | if (!ret) |
810 | return sprintf(buf, "%u\n", limit); | |
811 | } | |
812 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
813 | } | |
814 | ||
6dad2a29 BP |
815 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
816 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
817 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
818 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
819 | cpufreq_freq_attr_ro(scaling_available_governors); | |
820 | cpufreq_freq_attr_ro(scaling_driver); | |
821 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
822 | cpufreq_freq_attr_ro(bios_limit); | |
823 | cpufreq_freq_attr_ro(related_cpus); | |
824 | cpufreq_freq_attr_ro(affected_cpus); | |
825 | cpufreq_freq_attr_rw(scaling_min_freq); | |
826 | cpufreq_freq_attr_rw(scaling_max_freq); | |
827 | cpufreq_freq_attr_rw(scaling_governor); | |
828 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 829 | |
905d77cd | 830 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
831 | &cpuinfo_min_freq.attr, |
832 | &cpuinfo_max_freq.attr, | |
ed129784 | 833 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
834 | &scaling_min_freq.attr, |
835 | &scaling_max_freq.attr, | |
836 | &affected_cpus.attr, | |
e8628dd0 | 837 | &related_cpus.attr, |
1da177e4 LT |
838 | &scaling_governor.attr, |
839 | &scaling_driver.attr, | |
840 | &scaling_available_governors.attr, | |
9e76988e | 841 | &scaling_setspeed.attr, |
1da177e4 LT |
842 | NULL |
843 | }; | |
844 | ||
29464f28 DJ |
845 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
846 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 847 | |
29464f28 | 848 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 849 | { |
905d77cd DJ |
850 | struct cpufreq_policy *policy = to_policy(kobj); |
851 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 852 | ssize_t ret; |
6eed9404 VK |
853 | |
854 | if (!down_read_trylock(&cpufreq_rwsem)) | |
1b750e3b | 855 | return -EINVAL; |
5a01f2e8 | 856 | |
ad7722da | 857 | down_read(&policy->rwsem); |
5a01f2e8 | 858 | |
e08f5f5b GS |
859 | if (fattr->show) |
860 | ret = fattr->show(policy, buf); | |
861 | else | |
862 | ret = -EIO; | |
863 | ||
ad7722da | 864 | up_read(&policy->rwsem); |
6eed9404 | 865 | up_read(&cpufreq_rwsem); |
1b750e3b | 866 | |
1da177e4 LT |
867 | return ret; |
868 | } | |
869 | ||
905d77cd DJ |
870 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
871 | const char *buf, size_t count) | |
1da177e4 | 872 | { |
905d77cd DJ |
873 | struct cpufreq_policy *policy = to_policy(kobj); |
874 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 875 | ssize_t ret = -EINVAL; |
6eed9404 | 876 | |
4f750c93 SB |
877 | get_online_cpus(); |
878 | ||
879 | if (!cpu_online(policy->cpu)) | |
880 | goto unlock; | |
881 | ||
6eed9404 | 882 | if (!down_read_trylock(&cpufreq_rwsem)) |
4f750c93 | 883 | goto unlock; |
5a01f2e8 | 884 | |
ad7722da | 885 | down_write(&policy->rwsem); |
5a01f2e8 | 886 | |
11e584cf VK |
887 | /* Updating inactive policies is invalid, so avoid doing that. */ |
888 | if (unlikely(policy_is_inactive(policy))) { | |
889 | ret = -EBUSY; | |
890 | goto unlock_policy_rwsem; | |
891 | } | |
892 | ||
e08f5f5b GS |
893 | if (fattr->store) |
894 | ret = fattr->store(policy, buf, count); | |
895 | else | |
896 | ret = -EIO; | |
897 | ||
11e584cf | 898 | unlock_policy_rwsem: |
ad7722da | 899 | up_write(&policy->rwsem); |
6eed9404 | 900 | |
6eed9404 | 901 | up_read(&cpufreq_rwsem); |
4f750c93 SB |
902 | unlock: |
903 | put_online_cpus(); | |
904 | ||
1da177e4 LT |
905 | return ret; |
906 | } | |
907 | ||
905d77cd | 908 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 909 | { |
905d77cd | 910 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 911 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
912 | complete(&policy->kobj_unregister); |
913 | } | |
914 | ||
52cf25d0 | 915 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
916 | .show = show, |
917 | .store = store, | |
918 | }; | |
919 | ||
920 | static struct kobj_type ktype_cpufreq = { | |
921 | .sysfs_ops = &sysfs_ops, | |
922 | .default_attrs = default_attrs, | |
923 | .release = cpufreq_sysfs_release, | |
924 | }; | |
925 | ||
2361be23 VK |
926 | struct kobject *cpufreq_global_kobject; |
927 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
928 | ||
929 | static int cpufreq_global_kobject_usage; | |
930 | ||
931 | int cpufreq_get_global_kobject(void) | |
932 | { | |
933 | if (!cpufreq_global_kobject_usage++) | |
934 | return kobject_add(cpufreq_global_kobject, | |
935 | &cpu_subsys.dev_root->kobj, "%s", "cpufreq"); | |
936 | ||
937 | return 0; | |
938 | } | |
939 | EXPORT_SYMBOL(cpufreq_get_global_kobject); | |
940 | ||
941 | void cpufreq_put_global_kobject(void) | |
942 | { | |
943 | if (!--cpufreq_global_kobject_usage) | |
944 | kobject_del(cpufreq_global_kobject); | |
945 | } | |
946 | EXPORT_SYMBOL(cpufreq_put_global_kobject); | |
947 | ||
948 | int cpufreq_sysfs_create_file(const struct attribute *attr) | |
949 | { | |
950 | int ret = cpufreq_get_global_kobject(); | |
951 | ||
952 | if (!ret) { | |
953 | ret = sysfs_create_file(cpufreq_global_kobject, attr); | |
954 | if (ret) | |
955 | cpufreq_put_global_kobject(); | |
956 | } | |
957 | ||
958 | return ret; | |
959 | } | |
960 | EXPORT_SYMBOL(cpufreq_sysfs_create_file); | |
961 | ||
962 | void cpufreq_sysfs_remove_file(const struct attribute *attr) | |
963 | { | |
964 | sysfs_remove_file(cpufreq_global_kobject, attr); | |
965 | cpufreq_put_global_kobject(); | |
966 | } | |
967 | EXPORT_SYMBOL(cpufreq_sysfs_remove_file); | |
968 | ||
87549141 VK |
969 | static int add_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) |
970 | { | |
971 | struct device *cpu_dev; | |
972 | ||
973 | pr_debug("%s: Adding symlink for CPU: %u\n", __func__, cpu); | |
974 | ||
975 | if (!policy) | |
976 | return 0; | |
977 | ||
978 | cpu_dev = get_cpu_device(cpu); | |
979 | if (WARN_ON(!cpu_dev)) | |
980 | return 0; | |
981 | ||
982 | return sysfs_create_link(&cpu_dev->kobj, &policy->kobj, "cpufreq"); | |
983 | } | |
984 | ||
985 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) | |
986 | { | |
987 | struct device *cpu_dev; | |
988 | ||
989 | pr_debug("%s: Removing symlink for CPU: %u\n", __func__, cpu); | |
990 | ||
991 | cpu_dev = get_cpu_device(cpu); | |
992 | if (WARN_ON(!cpu_dev)) | |
993 | return; | |
994 | ||
995 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); | |
996 | } | |
997 | ||
998 | /* Add/remove symlinks for all related CPUs */ | |
308b60e7 | 999 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
1000 | { |
1001 | unsigned int j; | |
1002 | int ret = 0; | |
1003 | ||
87549141 VK |
1004 | /* Some related CPUs might not be present (physically hotplugged) */ |
1005 | for_each_cpu_and(j, policy->related_cpus, cpu_present_mask) { | |
9d16f207 | 1006 | if (j == policy->kobj_cpu) |
19d6f7ec | 1007 | continue; |
19d6f7ec | 1008 | |
87549141 | 1009 | ret = add_cpu_dev_symlink(policy, j); |
71c3461e RW |
1010 | if (ret) |
1011 | break; | |
19d6f7ec | 1012 | } |
87549141 | 1013 | |
19d6f7ec DJ |
1014 | return ret; |
1015 | } | |
1016 | ||
87549141 VK |
1017 | static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy) |
1018 | { | |
1019 | unsigned int j; | |
1020 | ||
1021 | /* Some related CPUs might not be present (physically hotplugged) */ | |
1022 | for_each_cpu_and(j, policy->related_cpus, cpu_present_mask) { | |
1023 | if (j == policy->kobj_cpu) | |
1024 | continue; | |
1025 | ||
1026 | remove_cpu_dev_symlink(policy, j); | |
1027 | } | |
1028 | } | |
1029 | ||
308b60e7 | 1030 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy, |
8a25a2fd | 1031 | struct device *dev) |
909a694e DJ |
1032 | { |
1033 | struct freq_attr **drv_attr; | |
909a694e | 1034 | int ret = 0; |
909a694e | 1035 | |
909a694e | 1036 | /* set up files for this cpu device */ |
1c3d85dd | 1037 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 1038 | while (drv_attr && *drv_attr) { |
909a694e DJ |
1039 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
1040 | if (ret) | |
6d4e81ed | 1041 | return ret; |
909a694e DJ |
1042 | drv_attr++; |
1043 | } | |
1c3d85dd | 1044 | if (cpufreq_driver->get) { |
909a694e DJ |
1045 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
1046 | if (ret) | |
6d4e81ed | 1047 | return ret; |
909a694e | 1048 | } |
c034b02e DB |
1049 | |
1050 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1051 | if (ret) | |
6d4e81ed | 1052 | return ret; |
c034b02e | 1053 | |
1c3d85dd | 1054 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1055 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1056 | if (ret) | |
6d4e81ed | 1057 | return ret; |
e2f74f35 | 1058 | } |
909a694e | 1059 | |
6d4e81ed | 1060 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
1061 | } |
1062 | ||
1063 | static void cpufreq_init_policy(struct cpufreq_policy *policy) | |
1064 | { | |
6e2c89d1 | 1065 | struct cpufreq_governor *gov = NULL; |
e18f1682 SB |
1066 | struct cpufreq_policy new_policy; |
1067 | int ret = 0; | |
1068 | ||
d5b73cd8 | 1069 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 1070 | |
6e2c89d1 | 1071 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 1072 | gov = find_governor(policy->last_governor); |
6e2c89d1 | 1073 | if (gov) |
1074 | pr_debug("Restoring governor %s for cpu %d\n", | |
1075 | policy->governor->name, policy->cpu); | |
1076 | else | |
1077 | gov = CPUFREQ_DEFAULT_GOVERNOR; | |
1078 | ||
1079 | new_policy.governor = gov; | |
1080 | ||
a27a9ab7 JB |
1081 | /* Use the default policy if its valid. */ |
1082 | if (cpufreq_driver->setpolicy) | |
6e2c89d1 | 1083 | cpufreq_parse_governor(gov->name, &new_policy.policy, NULL); |
ecf7e461 DJ |
1084 | |
1085 | /* set default policy */ | |
037ce839 | 1086 | ret = cpufreq_set_policy(policy, &new_policy); |
ecf7e461 | 1087 | if (ret) { |
2d06d8c4 | 1088 | pr_debug("setting policy failed\n"); |
1c3d85dd RW |
1089 | if (cpufreq_driver->exit) |
1090 | cpufreq_driver->exit(policy); | |
ecf7e461 | 1091 | } |
909a694e DJ |
1092 | } |
1093 | ||
d8d3b471 | 1094 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, |
42f921a6 | 1095 | unsigned int cpu, struct device *dev) |
fcf80582 | 1096 | { |
9c0ebcf7 | 1097 | int ret = 0; |
fcf80582 | 1098 | |
bb29ae15 VK |
1099 | /* Has this CPU been taken care of already? */ |
1100 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1101 | return 0; | |
1102 | ||
9c0ebcf7 | 1103 | if (has_target()) { |
3de9bdeb VK |
1104 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1105 | if (ret) { | |
1106 | pr_err("%s: Failed to stop governor\n", __func__); | |
1107 | return ret; | |
1108 | } | |
1109 | } | |
fcf80582 | 1110 | |
ad7722da | 1111 | down_write(&policy->rwsem); |
fcf80582 | 1112 | cpumask_set_cpu(cpu, policy->cpus); |
ad7722da | 1113 | up_write(&policy->rwsem); |
2eaa3e2d | 1114 | |
9c0ebcf7 | 1115 | if (has_target()) { |
e5c87b76 SK |
1116 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); |
1117 | if (!ret) | |
1118 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1119 | ||
1120 | if (ret) { | |
3de9bdeb VK |
1121 | pr_err("%s: Failed to start governor\n", __func__); |
1122 | return ret; | |
1123 | } | |
820c6ca2 | 1124 | } |
fcf80582 | 1125 | |
87549141 | 1126 | return 0; |
fcf80582 | 1127 | } |
1da177e4 | 1128 | |
8414809c SB |
1129 | static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu) |
1130 | { | |
1131 | struct cpufreq_policy *policy; | |
1132 | unsigned long flags; | |
1133 | ||
44871c9c | 1134 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
3914d379 | 1135 | policy = per_cpu(cpufreq_cpu_data, cpu); |
44871c9c | 1136 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
8414809c | 1137 | |
3914d379 VK |
1138 | if (likely(policy)) { |
1139 | /* Policy should be inactive here */ | |
1140 | WARN_ON(!policy_is_inactive(policy)); | |
37829029 VK |
1141 | |
1142 | down_write(&policy->rwsem); | |
1143 | policy->cpu = cpu; | |
35afd02e | 1144 | policy->governor = NULL; |
37829029 | 1145 | up_write(&policy->rwsem); |
3914d379 | 1146 | } |
6e2c89d1 | 1147 | |
8414809c SB |
1148 | return policy; |
1149 | } | |
1150 | ||
2fc3384d | 1151 | static struct cpufreq_policy *cpufreq_policy_alloc(struct device *dev) |
e9698cc5 SB |
1152 | { |
1153 | struct cpufreq_policy *policy; | |
2fc3384d | 1154 | int ret; |
e9698cc5 SB |
1155 | |
1156 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); | |
1157 | if (!policy) | |
1158 | return NULL; | |
1159 | ||
1160 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1161 | goto err_free_policy; | |
1162 | ||
1163 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1164 | goto err_free_cpumask; | |
1165 | ||
2fc3384d VK |
1166 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, &dev->kobj, |
1167 | "cpufreq"); | |
1168 | if (ret) { | |
1169 | pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); | |
1170 | goto err_free_rcpumask; | |
1171 | } | |
1172 | ||
c88a1f8b | 1173 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1174 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1175 | spin_lock_init(&policy->transition_lock); |
1176 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1177 | init_completion(&policy->kobj_unregister); |
1178 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1179 | |
2fc3384d | 1180 | policy->cpu = dev->id; |
87549141 VK |
1181 | |
1182 | /* Set this once on allocation */ | |
2fc3384d | 1183 | policy->kobj_cpu = dev->id; |
87549141 | 1184 | |
e9698cc5 SB |
1185 | return policy; |
1186 | ||
2fc3384d VK |
1187 | err_free_rcpumask: |
1188 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1189 | err_free_cpumask: |
1190 | free_cpumask_var(policy->cpus); | |
1191 | err_free_policy: | |
1192 | kfree(policy); | |
1193 | ||
1194 | return NULL; | |
1195 | } | |
1196 | ||
2fc3384d | 1197 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify) |
42f921a6 VK |
1198 | { |
1199 | struct kobject *kobj; | |
1200 | struct completion *cmp; | |
1201 | ||
2fc3384d VK |
1202 | if (notify) |
1203 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1204 | CPUFREQ_REMOVE_POLICY, policy); | |
fcd7af91 | 1205 | |
87549141 VK |
1206 | down_write(&policy->rwsem); |
1207 | cpufreq_remove_dev_symlink(policy); | |
42f921a6 VK |
1208 | kobj = &policy->kobj; |
1209 | cmp = &policy->kobj_unregister; | |
87549141 | 1210 | up_write(&policy->rwsem); |
42f921a6 VK |
1211 | kobject_put(kobj); |
1212 | ||
1213 | /* | |
1214 | * We need to make sure that the underlying kobj is | |
1215 | * actually not referenced anymore by anybody before we | |
1216 | * proceed with unloading. | |
1217 | */ | |
1218 | pr_debug("waiting for dropping of refcount\n"); | |
1219 | wait_for_completion(cmp); | |
1220 | pr_debug("wait complete\n"); | |
1221 | } | |
1222 | ||
3654c5cc | 1223 | static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify) |
e9698cc5 | 1224 | { |
988bed09 VK |
1225 | unsigned long flags; |
1226 | int cpu; | |
1227 | ||
1228 | /* Remove policy from list */ | |
1229 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1230 | list_del(&policy->policy_list); | |
1231 | ||
1232 | for_each_cpu(cpu, policy->related_cpus) | |
1233 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1234 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1235 | ||
3654c5cc | 1236 | cpufreq_policy_put_kobj(policy, notify); |
e9698cc5 SB |
1237 | free_cpumask_var(policy->related_cpus); |
1238 | free_cpumask_var(policy->cpus); | |
1239 | kfree(policy); | |
1240 | } | |
1241 | ||
23faf0b7 VK |
1242 | /** |
1243 | * cpufreq_add_dev - add a CPU device | |
1244 | * | |
1245 | * Adds the cpufreq interface for a CPU device. | |
1246 | * | |
1247 | * The Oracle says: try running cpufreq registration/unregistration concurrently | |
1248 | * with with cpu hotplugging and all hell will break loose. Tried to clean this | |
1249 | * mess up, but more thorough testing is needed. - Mathieu | |
1250 | */ | |
1251 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1da177e4 | 1252 | { |
fcf80582 | 1253 | unsigned int j, cpu = dev->id; |
65922465 | 1254 | int ret = -ENOMEM; |
7f0c020a | 1255 | struct cpufreq_policy *policy; |
1da177e4 | 1256 | unsigned long flags; |
87549141 | 1257 | bool recover_policy = !sif; |
c32b6b8e | 1258 | |
2d06d8c4 | 1259 | pr_debug("adding CPU %u\n", cpu); |
1da177e4 | 1260 | |
87549141 VK |
1261 | /* |
1262 | * Only possible if 'cpu' wasn't physically present earlier and we are | |
1263 | * here from subsys_interface add callback. A hotplug notifier will | |
1264 | * follow and we will handle it like logical CPU hotplug then. For now, | |
1265 | * just create the sysfs link. | |
1266 | */ | |
1267 | if (cpu_is_offline(cpu)) | |
1268 | return add_cpu_dev_symlink(per_cpu(cpufreq_cpu_data, cpu), cpu); | |
1269 | ||
6eed9404 VK |
1270 | if (!down_read_trylock(&cpufreq_rwsem)) |
1271 | return 0; | |
1272 | ||
bb29ae15 | 1273 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 VK |
1274 | policy = per_cpu(cpufreq_cpu_data, cpu); |
1275 | if (policy && !policy_is_inactive(policy)) { | |
1276 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); | |
1277 | ret = cpufreq_add_policy_cpu(policy, cpu, dev); | |
1278 | up_read(&cpufreq_rwsem); | |
1279 | return ret; | |
fcf80582 | 1280 | } |
1da177e4 | 1281 | |
72368d12 RW |
1282 | /* |
1283 | * Restore the saved policy when doing light-weight init and fall back | |
1284 | * to the full init if that fails. | |
1285 | */ | |
96bbbe4a | 1286 | policy = recover_policy ? cpufreq_policy_restore(cpu) : NULL; |
72368d12 | 1287 | if (!policy) { |
96bbbe4a | 1288 | recover_policy = false; |
2fc3384d | 1289 | policy = cpufreq_policy_alloc(dev); |
72368d12 | 1290 | if (!policy) |
8101f997 | 1291 | goto out_release_rwsem; |
72368d12 | 1292 | } |
0d66b91e | 1293 | |
835481d9 | 1294 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1295 | |
1da177e4 LT |
1296 | /* call driver. From then on the cpufreq must be able |
1297 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1298 | */ | |
1c3d85dd | 1299 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1300 | if (ret) { |
2d06d8c4 | 1301 | pr_debug("initialization failed\n"); |
8101f997 | 1302 | goto out_free_policy; |
1da177e4 | 1303 | } |
643ae6e8 | 1304 | |
6d4e81ed TV |
1305 | down_write(&policy->rwsem); |
1306 | ||
5a7e56a5 VK |
1307 | /* related cpus should atleast have policy->cpus */ |
1308 | cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); | |
1309 | ||
1310 | /* | |
1311 | * affected cpus must always be the one, which are online. We aren't | |
1312 | * managing offline cpus here. | |
1313 | */ | |
1314 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1315 | ||
96bbbe4a | 1316 | if (!recover_policy) { |
5a7e56a5 VK |
1317 | policy->user_policy.min = policy->min; |
1318 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1319 | |
988bed09 VK |
1320 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1321 | for_each_cpu(j, policy->related_cpus) | |
1322 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1323 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1324 | } | |
652ed95d | 1325 | |
2ed99e39 | 1326 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1327 | policy->cur = cpufreq_driver->get(policy->cpu); |
1328 | if (!policy->cur) { | |
1329 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1330 | goto out_exit_policy; |
da60ce9f VK |
1331 | } |
1332 | } | |
1333 | ||
d3916691 VK |
1334 | /* |
1335 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1336 | * frequency table present with cpufreq core. In such cases CPU might be | |
1337 | * unstable if it has to run on that frequency for long duration of time | |
1338 | * and so its better to set it to a frequency which is specified in | |
1339 | * freq-table. This also makes cpufreq stats inconsistent as | |
1340 | * cpufreq-stats would fail to register because current frequency of CPU | |
1341 | * isn't found in freq-table. | |
1342 | * | |
1343 | * Because we don't want this change to effect boot process badly, we go | |
1344 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1345 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1346 | * is initialized to zero). | |
1347 | * | |
1348 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1349 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1350 | * equal to target-freq. | |
1351 | */ | |
1352 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1353 | && has_target()) { | |
1354 | /* Are we running at unknown frequency ? */ | |
1355 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1356 | if (ret == -EINVAL) { | |
1357 | /* Warn user and fix it */ | |
1358 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1359 | __func__, policy->cpu, policy->cur); | |
1360 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1361 | CPUFREQ_RELATION_L); | |
1362 | ||
1363 | /* | |
1364 | * Reaching here after boot in a few seconds may not | |
1365 | * mean that system will remain stable at "unknown" | |
1366 | * frequency for longer duration. Hence, a BUG_ON(). | |
1367 | */ | |
1368 | BUG_ON(ret); | |
1369 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1370 | __func__, policy->cpu, policy->cur); | |
1371 | } | |
1372 | } | |
1373 | ||
a1531acd TR |
1374 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1375 | CPUFREQ_START, policy); | |
1376 | ||
96bbbe4a | 1377 | if (!recover_policy) { |
308b60e7 | 1378 | ret = cpufreq_add_dev_interface(policy, dev); |
a82fab29 | 1379 | if (ret) |
8101f997 | 1380 | goto out_exit_policy; |
fcd7af91 VK |
1381 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1382 | CPUFREQ_CREATE_POLICY, policy); | |
8ff69732 | 1383 | |
988bed09 VK |
1384 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1385 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1386 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1387 | } | |
9515f4d6 | 1388 | |
e18f1682 SB |
1389 | cpufreq_init_policy(policy); |
1390 | ||
96bbbe4a | 1391 | if (!recover_policy) { |
08fd8c1c VK |
1392 | policy->user_policy.policy = policy->policy; |
1393 | policy->user_policy.governor = policy->governor; | |
1394 | } | |
4e97b631 | 1395 | up_write(&policy->rwsem); |
08fd8c1c | 1396 | |
038c5b3e | 1397 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1398 | |
6eed9404 VK |
1399 | up_read(&cpufreq_rwsem); |
1400 | ||
7c45cf31 VK |
1401 | /* Callback for handling stuff after policy is ready */ |
1402 | if (cpufreq_driver->ready) | |
1403 | cpufreq_driver->ready(policy); | |
1404 | ||
2d06d8c4 | 1405 | pr_debug("initialization complete\n"); |
87c32271 | 1406 | |
1da177e4 LT |
1407 | return 0; |
1408 | ||
8101f997 | 1409 | out_exit_policy: |
7106e02b PB |
1410 | up_write(&policy->rwsem); |
1411 | ||
da60ce9f VK |
1412 | if (cpufreq_driver->exit) |
1413 | cpufreq_driver->exit(policy); | |
8101f997 | 1414 | out_free_policy: |
3654c5cc | 1415 | cpufreq_policy_free(policy, recover_policy); |
8101f997 | 1416 | out_release_rwsem: |
6eed9404 VK |
1417 | up_read(&cpufreq_rwsem); |
1418 | ||
1da177e4 LT |
1419 | return ret; |
1420 | } | |
1421 | ||
cedb70af | 1422 | static int __cpufreq_remove_dev_prepare(struct device *dev, |
96bbbe4a | 1423 | struct subsys_interface *sif) |
1da177e4 | 1424 | { |
9591becb VK |
1425 | unsigned int cpu = dev->id; |
1426 | int ret = 0; | |
3a3e9e06 | 1427 | struct cpufreq_policy *policy; |
1da177e4 | 1428 | |
b8eed8af | 1429 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1430 | |
988bed09 | 1431 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1432 | if (!policy) { |
b8eed8af | 1433 | pr_debug("%s: No cpu_data found\n", __func__); |
1da177e4 LT |
1434 | return -EINVAL; |
1435 | } | |
1da177e4 | 1436 | |
9c0ebcf7 | 1437 | if (has_target()) { |
3de9bdeb VK |
1438 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1439 | if (ret) { | |
1440 | pr_err("%s: Failed to stop governor\n", __func__); | |
1441 | return ret; | |
1442 | } | |
db5f2995 | 1443 | } |
1da177e4 | 1444 | |
4573237b | 1445 | down_write(&policy->rwsem); |
9591becb | 1446 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1447 | |
9591becb VK |
1448 | if (policy_is_inactive(policy)) { |
1449 | if (has_target()) | |
1450 | strncpy(policy->last_governor, policy->governor->name, | |
1451 | CPUFREQ_NAME_LEN); | |
1452 | } else if (cpu == policy->cpu) { | |
1453 | /* Nominate new CPU */ | |
1454 | policy->cpu = cpumask_any(policy->cpus); | |
1455 | } | |
4573237b | 1456 | up_write(&policy->rwsem); |
084f3493 | 1457 | |
9591becb VK |
1458 | /* Start governor again for active policy */ |
1459 | if (!policy_is_inactive(policy)) { | |
1460 | if (has_target()) { | |
1461 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
1462 | if (!ret) | |
1463 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1bfb425b | 1464 | |
9591becb VK |
1465 | if (ret) |
1466 | pr_err("%s: Failed to start governor\n", __func__); | |
1467 | } | |
1468 | } else if (cpufreq_driver->stop_cpu) { | |
367dc4aa | 1469 | cpufreq_driver->stop_cpu(policy); |
9591becb | 1470 | } |
1da177e4 | 1471 | |
9591becb | 1472 | return ret; |
cedb70af SB |
1473 | } |
1474 | ||
1475 | static int __cpufreq_remove_dev_finish(struct device *dev, | |
96bbbe4a | 1476 | struct subsys_interface *sif) |
cedb70af | 1477 | { |
988bed09 | 1478 | unsigned int cpu = dev->id; |
cedb70af | 1479 | int ret; |
9591becb | 1480 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
cedb70af SB |
1481 | |
1482 | if (!policy) { | |
1483 | pr_debug("%s: No cpu_data found\n", __func__); | |
1484 | return -EINVAL; | |
1485 | } | |
1486 | ||
9591becb VK |
1487 | /* Only proceed for inactive policies */ |
1488 | if (!policy_is_inactive(policy)) | |
87549141 | 1489 | return 0; |
87549141 VK |
1490 | |
1491 | /* If cpu is last user of policy, free policy */ | |
1492 | if (has_target()) { | |
1493 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
1494 | if (ret) { | |
1495 | pr_err("%s: Failed to exit governor\n", __func__); | |
1496 | return ret; | |
1497 | } | |
27ecddc2 | 1498 | } |
1da177e4 | 1499 | |
87549141 VK |
1500 | /* |
1501 | * Perform the ->exit() even during light-weight tear-down, | |
1502 | * since this is a core component, and is essential for the | |
1503 | * subsequent light-weight ->init() to succeed. | |
1504 | */ | |
1505 | if (cpufreq_driver->exit) | |
1506 | cpufreq_driver->exit(policy); | |
1507 | ||
3654c5cc | 1508 | /* Free the policy only if the driver is getting removed. */ |
87549141 | 1509 | if (sif) |
3654c5cc | 1510 | cpufreq_policy_free(policy, true); |
87549141 | 1511 | |
1da177e4 LT |
1512 | return 0; |
1513 | } | |
1514 | ||
cedb70af | 1515 | /** |
27a862e9 | 1516 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1517 | * |
1518 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1519 | */ |
8a25a2fd | 1520 | static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1521 | { |
8a25a2fd | 1522 | unsigned int cpu = dev->id; |
27a862e9 | 1523 | int ret; |
ec28297a | 1524 | |
87549141 VK |
1525 | /* |
1526 | * Only possible if 'cpu' is getting physically removed now. A hotplug | |
1527 | * notifier should have already been called and we just need to remove | |
1528 | * link or free policy here. | |
1529 | */ | |
1530 | if (cpu_is_offline(cpu)) { | |
1531 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
1532 | struct cpumask mask; | |
1533 | ||
1534 | if (!policy) | |
1535 | return 0; | |
1536 | ||
1537 | cpumask_copy(&mask, policy->related_cpus); | |
1538 | cpumask_clear_cpu(cpu, &mask); | |
1539 | ||
1540 | /* | |
1541 | * Free policy only if all policy->related_cpus are removed | |
1542 | * physically. | |
1543 | */ | |
1544 | if (cpumask_intersects(&mask, cpu_present_mask)) { | |
1545 | remove_cpu_dev_symlink(policy, cpu); | |
1546 | return 0; | |
1547 | } | |
1548 | ||
3654c5cc | 1549 | cpufreq_policy_free(policy, true); |
ec28297a | 1550 | return 0; |
87549141 | 1551 | } |
ec28297a | 1552 | |
96bbbe4a | 1553 | ret = __cpufreq_remove_dev_prepare(dev, sif); |
27a862e9 VK |
1554 | |
1555 | if (!ret) | |
96bbbe4a | 1556 | ret = __cpufreq_remove_dev_finish(dev, sif); |
27a862e9 VK |
1557 | |
1558 | return ret; | |
5a01f2e8 VP |
1559 | } |
1560 | ||
65f27f38 | 1561 | static void handle_update(struct work_struct *work) |
1da177e4 | 1562 | { |
65f27f38 DH |
1563 | struct cpufreq_policy *policy = |
1564 | container_of(work, struct cpufreq_policy, update); | |
1565 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1566 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1567 | cpufreq_update_policy(cpu); |
1568 | } | |
1569 | ||
1570 | /** | |
bb176f7d VK |
1571 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1572 | * in deep trouble. | |
a1e1dc41 | 1573 | * @policy: policy managing CPUs |
1da177e4 LT |
1574 | * @new_freq: CPU frequency the CPU actually runs at |
1575 | * | |
29464f28 DJ |
1576 | * We adjust to current frequency first, and need to clean up later. |
1577 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1578 | */ |
a1e1dc41 | 1579 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1580 | unsigned int new_freq) |
1da177e4 LT |
1581 | { |
1582 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1583 | |
e837f9b5 | 1584 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1585 | policy->cur, new_freq); |
1da177e4 | 1586 | |
a1e1dc41 | 1587 | freqs.old = policy->cur; |
1da177e4 | 1588 | freqs.new = new_freq; |
b43a7ffb | 1589 | |
8fec051e VK |
1590 | cpufreq_freq_transition_begin(policy, &freqs); |
1591 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1592 | } |
1593 | ||
32ee8c3e | 1594 | /** |
4ab70df4 | 1595 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1596 | * @cpu: CPU number |
1597 | * | |
1598 | * This is the last known freq, without actually getting it from the driver. | |
1599 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1600 | */ | |
1601 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1602 | { | |
9e21ba8b | 1603 | struct cpufreq_policy *policy; |
e08f5f5b | 1604 | unsigned int ret_freq = 0; |
95235ca2 | 1605 | |
1c3d85dd RW |
1606 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1607 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1608 | |
1609 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1610 | if (policy) { |
e08f5f5b | 1611 | ret_freq = policy->cur; |
95235ca2 VP |
1612 | cpufreq_cpu_put(policy); |
1613 | } | |
1614 | ||
4d34a67d | 1615 | return ret_freq; |
95235ca2 VP |
1616 | } |
1617 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1618 | ||
3d737108 JB |
1619 | /** |
1620 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1621 | * @cpu: CPU number | |
1622 | * | |
1623 | * Just return the max possible frequency for a given CPU. | |
1624 | */ | |
1625 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1626 | { | |
1627 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1628 | unsigned int ret_freq = 0; | |
1629 | ||
1630 | if (policy) { | |
1631 | ret_freq = policy->max; | |
1632 | cpufreq_cpu_put(policy); | |
1633 | } | |
1634 | ||
1635 | return ret_freq; | |
1636 | } | |
1637 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1638 | ||
d92d50a4 | 1639 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1640 | { |
e08f5f5b | 1641 | unsigned int ret_freq = 0; |
5800043b | 1642 | |
1c3d85dd | 1643 | if (!cpufreq_driver->get) |
4d34a67d | 1644 | return ret_freq; |
1da177e4 | 1645 | |
d92d50a4 | 1646 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1647 | |
11e584cf VK |
1648 | /* Updating inactive policies is invalid, so avoid doing that. */ |
1649 | if (unlikely(policy_is_inactive(policy))) | |
1650 | return ret_freq; | |
1651 | ||
e08f5f5b | 1652 | if (ret_freq && policy->cur && |
1c3d85dd | 1653 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1654 | /* verify no discrepancy between actual and |
1655 | saved value exists */ | |
1656 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1657 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1658 | schedule_work(&policy->update); |
1659 | } | |
1660 | } | |
1661 | ||
4d34a67d | 1662 | return ret_freq; |
5a01f2e8 | 1663 | } |
1da177e4 | 1664 | |
5a01f2e8 VP |
1665 | /** |
1666 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1667 | * @cpu: CPU number | |
1668 | * | |
1669 | * Get the CPU current (static) CPU frequency | |
1670 | */ | |
1671 | unsigned int cpufreq_get(unsigned int cpu) | |
1672 | { | |
999976e0 | 1673 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1674 | unsigned int ret_freq = 0; |
5a01f2e8 | 1675 | |
999976e0 AP |
1676 | if (policy) { |
1677 | down_read(&policy->rwsem); | |
d92d50a4 | 1678 | ret_freq = __cpufreq_get(policy); |
999976e0 | 1679 | up_read(&policy->rwsem); |
5a01f2e8 | 1680 | |
999976e0 AP |
1681 | cpufreq_cpu_put(policy); |
1682 | } | |
6eed9404 | 1683 | |
4d34a67d | 1684 | return ret_freq; |
1da177e4 LT |
1685 | } |
1686 | EXPORT_SYMBOL(cpufreq_get); | |
1687 | ||
8a25a2fd KS |
1688 | static struct subsys_interface cpufreq_interface = { |
1689 | .name = "cpufreq", | |
1690 | .subsys = &cpu_subsys, | |
1691 | .add_dev = cpufreq_add_dev, | |
1692 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1693 | }; |
1694 | ||
e28867ea VK |
1695 | /* |
1696 | * In case platform wants some specific frequency to be configured | |
1697 | * during suspend.. | |
1698 | */ | |
1699 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1700 | { | |
1701 | int ret; | |
1702 | ||
1703 | if (!policy->suspend_freq) { | |
1704 | pr_err("%s: suspend_freq can't be zero\n", __func__); | |
1705 | return -EINVAL; | |
1706 | } | |
1707 | ||
1708 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1709 | policy->suspend_freq); | |
1710 | ||
1711 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1712 | CPUFREQ_RELATION_H); | |
1713 | if (ret) | |
1714 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1715 | __func__, policy->suspend_freq, ret); | |
1716 | ||
1717 | return ret; | |
1718 | } | |
1719 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1720 | ||
42d4dc3f | 1721 | /** |
2f0aea93 | 1722 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1723 | * |
2f0aea93 VK |
1724 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1725 | * as some platforms can't change frequency after this point in suspend cycle. | |
1726 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1727 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1728 | */ |
2f0aea93 | 1729 | void cpufreq_suspend(void) |
42d4dc3f | 1730 | { |
3a3e9e06 | 1731 | struct cpufreq_policy *policy; |
42d4dc3f | 1732 | |
2f0aea93 VK |
1733 | if (!cpufreq_driver) |
1734 | return; | |
42d4dc3f | 1735 | |
2f0aea93 | 1736 | if (!has_target()) |
b1b12bab | 1737 | goto suspend; |
42d4dc3f | 1738 | |
2f0aea93 VK |
1739 | pr_debug("%s: Suspending Governors\n", __func__); |
1740 | ||
f963735a | 1741 | for_each_active_policy(policy) { |
2f0aea93 VK |
1742 | if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP)) |
1743 | pr_err("%s: Failed to stop governor for policy: %p\n", | |
1744 | __func__, policy); | |
1745 | else if (cpufreq_driver->suspend | |
1746 | && cpufreq_driver->suspend(policy)) | |
1747 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1748 | policy); | |
42d4dc3f | 1749 | } |
b1b12bab VK |
1750 | |
1751 | suspend: | |
1752 | cpufreq_suspended = true; | |
42d4dc3f BH |
1753 | } |
1754 | ||
1da177e4 | 1755 | /** |
2f0aea93 | 1756 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1757 | * |
2f0aea93 VK |
1758 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1759 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1760 | */ |
2f0aea93 | 1761 | void cpufreq_resume(void) |
1da177e4 | 1762 | { |
3a3e9e06 | 1763 | struct cpufreq_policy *policy; |
1da177e4 | 1764 | |
2f0aea93 VK |
1765 | if (!cpufreq_driver) |
1766 | return; | |
1da177e4 | 1767 | |
8e30444e LT |
1768 | cpufreq_suspended = false; |
1769 | ||
2f0aea93 | 1770 | if (!has_target()) |
e00e56df | 1771 | return; |
1da177e4 | 1772 | |
2f0aea93 | 1773 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1774 | |
f963735a | 1775 | for_each_active_policy(policy) { |
0c5aa405 VK |
1776 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) |
1777 | pr_err("%s: Failed to resume driver: %p\n", __func__, | |
1778 | policy); | |
1779 | else if (__cpufreq_governor(policy, CPUFREQ_GOV_START) | |
2f0aea93 VK |
1780 | || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS)) |
1781 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1782 | __func__, policy); | |
2f0aea93 | 1783 | } |
c75de0ac VK |
1784 | |
1785 | /* | |
1786 | * schedule call cpufreq_update_policy() for first-online CPU, as that | |
1787 | * wouldn't be hotplugged-out on suspend. It will verify that the | |
1788 | * current freq is in sync with what we believe it to be. | |
1789 | */ | |
1790 | policy = cpufreq_cpu_get_raw(cpumask_first(cpu_online_mask)); | |
1791 | if (WARN_ON(!policy)) | |
1792 | return; | |
1793 | ||
1794 | schedule_work(&policy->update); | |
2f0aea93 | 1795 | } |
1da177e4 | 1796 | |
9d95046e BP |
1797 | /** |
1798 | * cpufreq_get_current_driver - return current driver's name | |
1799 | * | |
1800 | * Return the name string of the currently loaded cpufreq driver | |
1801 | * or NULL, if none. | |
1802 | */ | |
1803 | const char *cpufreq_get_current_driver(void) | |
1804 | { | |
1c3d85dd RW |
1805 | if (cpufreq_driver) |
1806 | return cpufreq_driver->name; | |
1807 | ||
1808 | return NULL; | |
9d95046e BP |
1809 | } |
1810 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1811 | |
51315cdf TP |
1812 | /** |
1813 | * cpufreq_get_driver_data - return current driver data | |
1814 | * | |
1815 | * Return the private data of the currently loaded cpufreq | |
1816 | * driver, or NULL if no cpufreq driver is loaded. | |
1817 | */ | |
1818 | void *cpufreq_get_driver_data(void) | |
1819 | { | |
1820 | if (cpufreq_driver) | |
1821 | return cpufreq_driver->driver_data; | |
1822 | ||
1823 | return NULL; | |
1824 | } | |
1825 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1826 | ||
1da177e4 LT |
1827 | /********************************************************************* |
1828 | * NOTIFIER LISTS INTERFACE * | |
1829 | *********************************************************************/ | |
1830 | ||
1831 | /** | |
1832 | * cpufreq_register_notifier - register a driver with cpufreq | |
1833 | * @nb: notifier function to register | |
1834 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1835 | * | |
32ee8c3e | 1836 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1837 | * are notified about clock rate changes (once before and once after |
1838 | * the transition), or a list of drivers that are notified about | |
1839 | * changes in cpufreq policy. | |
1840 | * | |
1841 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1842 | * blocking_notifier_chain_register. |
1da177e4 LT |
1843 | */ |
1844 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1845 | { | |
1846 | int ret; | |
1847 | ||
d5aaffa9 DB |
1848 | if (cpufreq_disabled()) |
1849 | return -EINVAL; | |
1850 | ||
74212ca4 CEB |
1851 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1852 | ||
1da177e4 LT |
1853 | switch (list) { |
1854 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1855 | ret = srcu_notifier_chain_register( |
e041c683 | 1856 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1857 | break; |
1858 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1859 | ret = blocking_notifier_chain_register( |
1860 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1861 | break; |
1862 | default: | |
1863 | ret = -EINVAL; | |
1864 | } | |
1da177e4 LT |
1865 | |
1866 | return ret; | |
1867 | } | |
1868 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1869 | ||
1da177e4 LT |
1870 | /** |
1871 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1872 | * @nb: notifier block to be unregistered | |
bb176f7d | 1873 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1874 | * |
1875 | * Remove a driver from the CPU frequency notifier list. | |
1876 | * | |
1877 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1878 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1879 | */ |
1880 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1881 | { | |
1882 | int ret; | |
1883 | ||
d5aaffa9 DB |
1884 | if (cpufreq_disabled()) |
1885 | return -EINVAL; | |
1886 | ||
1da177e4 LT |
1887 | switch (list) { |
1888 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1889 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1890 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1891 | break; |
1892 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1893 | ret = blocking_notifier_chain_unregister( |
1894 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1895 | break; |
1896 | default: | |
1897 | ret = -EINVAL; | |
1898 | } | |
1da177e4 LT |
1899 | |
1900 | return ret; | |
1901 | } | |
1902 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1903 | ||
1904 | ||
1905 | /********************************************************************* | |
1906 | * GOVERNORS * | |
1907 | *********************************************************************/ | |
1908 | ||
1c03a2d0 VK |
1909 | /* Must set freqs->new to intermediate frequency */ |
1910 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1911 | struct cpufreq_freqs *freqs, int index) | |
1912 | { | |
1913 | int ret; | |
1914 | ||
1915 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1916 | ||
1917 | /* We don't need to switch to intermediate freq */ | |
1918 | if (!freqs->new) | |
1919 | return 0; | |
1920 | ||
1921 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1922 | __func__, policy->cpu, freqs->old, freqs->new); | |
1923 | ||
1924 | cpufreq_freq_transition_begin(policy, freqs); | |
1925 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1926 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1927 | ||
1928 | if (ret) | |
1929 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1930 | __func__, ret); | |
1931 | ||
1932 | return ret; | |
1933 | } | |
1934 | ||
8d65775d VK |
1935 | static int __target_index(struct cpufreq_policy *policy, |
1936 | struct cpufreq_frequency_table *freq_table, int index) | |
1937 | { | |
1c03a2d0 VK |
1938 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1939 | unsigned int intermediate_freq = 0; | |
8d65775d VK |
1940 | int retval = -EINVAL; |
1941 | bool notify; | |
1942 | ||
1943 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
8d65775d | 1944 | if (notify) { |
1c03a2d0 VK |
1945 | /* Handle switching to intermediate frequency */ |
1946 | if (cpufreq_driver->get_intermediate) { | |
1947 | retval = __target_intermediate(policy, &freqs, index); | |
1948 | if (retval) | |
1949 | return retval; | |
1950 | ||
1951 | intermediate_freq = freqs.new; | |
1952 | /* Set old freq to intermediate */ | |
1953 | if (intermediate_freq) | |
1954 | freqs.old = freqs.new; | |
1955 | } | |
8d65775d | 1956 | |
1c03a2d0 | 1957 | freqs.new = freq_table[index].frequency; |
8d65775d VK |
1958 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1959 | __func__, policy->cpu, freqs.old, freqs.new); | |
1960 | ||
1961 | cpufreq_freq_transition_begin(policy, &freqs); | |
1962 | } | |
1963 | ||
1964 | retval = cpufreq_driver->target_index(policy, index); | |
1965 | if (retval) | |
1966 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1967 | retval); | |
1968 | ||
1c03a2d0 | 1969 | if (notify) { |
8d65775d VK |
1970 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1971 | ||
1c03a2d0 VK |
1972 | /* |
1973 | * Failed after setting to intermediate freq? Driver should have | |
1974 | * reverted back to initial frequency and so should we. Check | |
1975 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1976 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1977 | */ |
1978 | if (unlikely(retval && intermediate_freq)) { | |
1979 | freqs.old = intermediate_freq; | |
1980 | freqs.new = policy->restore_freq; | |
1981 | cpufreq_freq_transition_begin(policy, &freqs); | |
1982 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1983 | } | |
1984 | } | |
1985 | ||
8d65775d VK |
1986 | return retval; |
1987 | } | |
1988 | ||
1da177e4 LT |
1989 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1990 | unsigned int target_freq, | |
1991 | unsigned int relation) | |
1992 | { | |
7249924e | 1993 | unsigned int old_target_freq = target_freq; |
8d65775d | 1994 | int retval = -EINVAL; |
c32b6b8e | 1995 | |
a7b422cd KRW |
1996 | if (cpufreq_disabled()) |
1997 | return -ENODEV; | |
1998 | ||
7249924e VK |
1999 | /* Make sure that target_freq is within supported range */ |
2000 | if (target_freq > policy->max) | |
2001 | target_freq = policy->max; | |
2002 | if (target_freq < policy->min) | |
2003 | target_freq = policy->min; | |
2004 | ||
2005 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 2006 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 2007 | |
9c0ebcf7 VK |
2008 | /* |
2009 | * This might look like a redundant call as we are checking it again | |
2010 | * after finding index. But it is left intentionally for cases where | |
2011 | * exactly same freq is called again and so we can save on few function | |
2012 | * calls. | |
2013 | */ | |
5a1c0228 VK |
2014 | if (target_freq == policy->cur) |
2015 | return 0; | |
2016 | ||
1c03a2d0 VK |
2017 | /* Save last value to restore later on errors */ |
2018 | policy->restore_freq = policy->cur; | |
2019 | ||
1c3d85dd RW |
2020 | if (cpufreq_driver->target) |
2021 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
9c0ebcf7 VK |
2022 | else if (cpufreq_driver->target_index) { |
2023 | struct cpufreq_frequency_table *freq_table; | |
2024 | int index; | |
90d45d17 | 2025 | |
9c0ebcf7 VK |
2026 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2027 | if (unlikely(!freq_table)) { | |
2028 | pr_err("%s: Unable to find freq_table\n", __func__); | |
2029 | goto out; | |
2030 | } | |
2031 | ||
2032 | retval = cpufreq_frequency_table_target(policy, freq_table, | |
2033 | target_freq, relation, &index); | |
2034 | if (unlikely(retval)) { | |
2035 | pr_err("%s: Unable to find matching freq\n", __func__); | |
2036 | goto out; | |
2037 | } | |
2038 | ||
d4019f0a | 2039 | if (freq_table[index].frequency == policy->cur) { |
9c0ebcf7 | 2040 | retval = 0; |
d4019f0a VK |
2041 | goto out; |
2042 | } | |
2043 | ||
8d65775d | 2044 | retval = __target_index(policy, freq_table, index); |
9c0ebcf7 VK |
2045 | } |
2046 | ||
2047 | out: | |
1da177e4 LT |
2048 | return retval; |
2049 | } | |
2050 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2051 | ||
1da177e4 LT |
2052 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2053 | unsigned int target_freq, | |
2054 | unsigned int relation) | |
2055 | { | |
f1829e4a | 2056 | int ret = -EINVAL; |
1da177e4 | 2057 | |
ad7722da | 2058 | down_write(&policy->rwsem); |
1da177e4 LT |
2059 | |
2060 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2061 | ||
ad7722da | 2062 | up_write(&policy->rwsem); |
1da177e4 | 2063 | |
1da177e4 LT |
2064 | return ret; |
2065 | } | |
2066 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2067 | ||
e08f5f5b GS |
2068 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
2069 | unsigned int event) | |
1da177e4 | 2070 | { |
cc993cab | 2071 | int ret; |
6afde10c TR |
2072 | |
2073 | /* Only must be defined when default governor is known to have latency | |
2074 | restrictions, like e.g. conservative or ondemand. | |
2075 | That this is the case is already ensured in Kconfig | |
2076 | */ | |
2077 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
2078 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
2079 | #else | |
2080 | struct cpufreq_governor *gov = NULL; | |
2081 | #endif | |
1c256245 | 2082 | |
2f0aea93 VK |
2083 | /* Don't start any governor operations if we are entering suspend */ |
2084 | if (cpufreq_suspended) | |
2085 | return 0; | |
cb57720b EZ |
2086 | /* |
2087 | * Governor might not be initiated here if ACPI _PPC changed | |
2088 | * notification happened, so check it. | |
2089 | */ | |
2090 | if (!policy->governor) | |
2091 | return -EINVAL; | |
2f0aea93 | 2092 | |
1c256245 TR |
2093 | if (policy->governor->max_transition_latency && |
2094 | policy->cpuinfo.transition_latency > | |
2095 | policy->governor->max_transition_latency) { | |
6afde10c TR |
2096 | if (!gov) |
2097 | return -EINVAL; | |
2098 | else { | |
e837f9b5 JP |
2099 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
2100 | policy->governor->name, gov->name); | |
6afde10c TR |
2101 | policy->governor = gov; |
2102 | } | |
1c256245 | 2103 | } |
1da177e4 | 2104 | |
fe492f3f VK |
2105 | if (event == CPUFREQ_GOV_POLICY_INIT) |
2106 | if (!try_module_get(policy->governor->owner)) | |
2107 | return -EINVAL; | |
1da177e4 | 2108 | |
2d06d8c4 | 2109 | pr_debug("__cpufreq_governor for CPU %u, event %u\n", |
e837f9b5 | 2110 | policy->cpu, event); |
95731ebb XC |
2111 | |
2112 | mutex_lock(&cpufreq_governor_lock); | |
56d07db2 | 2113 | if ((policy->governor_enabled && event == CPUFREQ_GOV_START) |
f73d3933 VK |
2114 | || (!policy->governor_enabled |
2115 | && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) { | |
95731ebb XC |
2116 | mutex_unlock(&cpufreq_governor_lock); |
2117 | return -EBUSY; | |
2118 | } | |
2119 | ||
2120 | if (event == CPUFREQ_GOV_STOP) | |
2121 | policy->governor_enabled = false; | |
2122 | else if (event == CPUFREQ_GOV_START) | |
2123 | policy->governor_enabled = true; | |
2124 | ||
2125 | mutex_unlock(&cpufreq_governor_lock); | |
2126 | ||
1da177e4 LT |
2127 | ret = policy->governor->governor(policy, event); |
2128 | ||
4d5dcc42 VK |
2129 | if (!ret) { |
2130 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
2131 | policy->governor->initialized++; | |
2132 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
2133 | policy->governor->initialized--; | |
95731ebb XC |
2134 | } else { |
2135 | /* Restore original values */ | |
2136 | mutex_lock(&cpufreq_governor_lock); | |
2137 | if (event == CPUFREQ_GOV_STOP) | |
2138 | policy->governor_enabled = true; | |
2139 | else if (event == CPUFREQ_GOV_START) | |
2140 | policy->governor_enabled = false; | |
2141 | mutex_unlock(&cpufreq_governor_lock); | |
4d5dcc42 | 2142 | } |
b394058f | 2143 | |
fe492f3f VK |
2144 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
2145 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
2146 | module_put(policy->governor->owner); |
2147 | ||
2148 | return ret; | |
2149 | } | |
2150 | ||
1da177e4 LT |
2151 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2152 | { | |
3bcb09a3 | 2153 | int err; |
1da177e4 LT |
2154 | |
2155 | if (!governor) | |
2156 | return -EINVAL; | |
2157 | ||
a7b422cd KRW |
2158 | if (cpufreq_disabled()) |
2159 | return -ENODEV; | |
2160 | ||
3fc54d37 | 2161 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2162 | |
b394058f | 2163 | governor->initialized = 0; |
3bcb09a3 | 2164 | err = -EBUSY; |
42f91fa1 | 2165 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2166 | err = 0; |
2167 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2168 | } |
1da177e4 | 2169 | |
32ee8c3e | 2170 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2171 | return err; |
1da177e4 LT |
2172 | } |
2173 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2174 | ||
1da177e4 LT |
2175 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2176 | { | |
4573237b VK |
2177 | struct cpufreq_policy *policy; |
2178 | unsigned long flags; | |
90e41bac | 2179 | |
1da177e4 LT |
2180 | if (!governor) |
2181 | return; | |
2182 | ||
a7b422cd KRW |
2183 | if (cpufreq_disabled()) |
2184 | return; | |
2185 | ||
4573237b VK |
2186 | /* clear last_governor for all inactive policies */ |
2187 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
2188 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
2189 | if (!strcmp(policy->last_governor, governor->name)) { |
2190 | policy->governor = NULL; | |
4573237b | 2191 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 2192 | } |
90e41bac | 2193 | } |
4573237b | 2194 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 2195 | |
3fc54d37 | 2196 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2197 | list_del(&governor->governor_list); |
3fc54d37 | 2198 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2199 | return; |
2200 | } | |
2201 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2202 | ||
2203 | ||
1da177e4 LT |
2204 | /********************************************************************* |
2205 | * POLICY INTERFACE * | |
2206 | *********************************************************************/ | |
2207 | ||
2208 | /** | |
2209 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2210 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2211 | * is written | |
1da177e4 LT |
2212 | * |
2213 | * Reads the current cpufreq policy. | |
2214 | */ | |
2215 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2216 | { | |
2217 | struct cpufreq_policy *cpu_policy; | |
2218 | if (!policy) | |
2219 | return -EINVAL; | |
2220 | ||
2221 | cpu_policy = cpufreq_cpu_get(cpu); | |
2222 | if (!cpu_policy) | |
2223 | return -EINVAL; | |
2224 | ||
d5b73cd8 | 2225 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2226 | |
2227 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2228 | return 0; |
2229 | } | |
2230 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2231 | ||
153d7f3f | 2232 | /* |
037ce839 VK |
2233 | * policy : current policy. |
2234 | * new_policy: policy to be set. | |
153d7f3f | 2235 | */ |
037ce839 | 2236 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2237 | struct cpufreq_policy *new_policy) |
1da177e4 | 2238 | { |
d9a789c7 RW |
2239 | struct cpufreq_governor *old_gov; |
2240 | int ret; | |
1da177e4 | 2241 | |
e837f9b5 JP |
2242 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2243 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2244 | |
d5b73cd8 | 2245 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2246 | |
d9a789c7 RW |
2247 | if (new_policy->min > policy->max || new_policy->max < policy->min) |
2248 | return -EINVAL; | |
9c9a43ed | 2249 | |
1da177e4 | 2250 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2251 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2252 | if (ret) |
d9a789c7 | 2253 | return ret; |
1da177e4 | 2254 | |
1da177e4 | 2255 | /* adjust if necessary - all reasons */ |
e041c683 | 2256 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2257 | CPUFREQ_ADJUST, new_policy); |
1da177e4 LT |
2258 | |
2259 | /* adjust if necessary - hardware incompatibility*/ | |
e041c683 | 2260 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2261 | CPUFREQ_INCOMPATIBLE, new_policy); |
1da177e4 | 2262 | |
bb176f7d VK |
2263 | /* |
2264 | * verify the cpu speed can be set within this limit, which might be | |
2265 | * different to the first one | |
2266 | */ | |
3a3e9e06 | 2267 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2268 | if (ret) |
d9a789c7 | 2269 | return ret; |
1da177e4 LT |
2270 | |
2271 | /* notification of the new policy */ | |
e041c683 | 2272 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2273 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2274 | |
3a3e9e06 VK |
2275 | policy->min = new_policy->min; |
2276 | policy->max = new_policy->max; | |
1da177e4 | 2277 | |
2d06d8c4 | 2278 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2279 | policy->min, policy->max); |
1da177e4 | 2280 | |
1c3d85dd | 2281 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2282 | policy->policy = new_policy->policy; |
2d06d8c4 | 2283 | pr_debug("setting range\n"); |
d9a789c7 RW |
2284 | return cpufreq_driver->setpolicy(new_policy); |
2285 | } | |
1da177e4 | 2286 | |
d9a789c7 RW |
2287 | if (new_policy->governor == policy->governor) |
2288 | goto out; | |
7bd353a9 | 2289 | |
d9a789c7 RW |
2290 | pr_debug("governor switch\n"); |
2291 | ||
2292 | /* save old, working values */ | |
2293 | old_gov = policy->governor; | |
2294 | /* end old governor */ | |
2295 | if (old_gov) { | |
2296 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
2297 | up_write(&policy->rwsem); | |
e5c87b76 | 2298 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
d9a789c7 | 2299 | down_write(&policy->rwsem); |
1da177e4 LT |
2300 | } |
2301 | ||
d9a789c7 RW |
2302 | /* start new governor */ |
2303 | policy->governor = new_policy->governor; | |
2304 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) { | |
2305 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_START)) | |
2306 | goto out; | |
2307 | ||
2308 | up_write(&policy->rwsem); | |
2309 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
2310 | down_write(&policy->rwsem); | |
2311 | } | |
2312 | ||
2313 | /* new governor failed, so re-start old one */ | |
2314 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2315 | if (old_gov) { | |
2316 | policy->governor = old_gov; | |
2317 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); | |
2318 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
2319 | } | |
2320 | ||
2321 | return -EINVAL; | |
2322 | ||
2323 | out: | |
2324 | pr_debug("governor: change or update limits\n"); | |
2325 | return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1da177e4 LT |
2326 | } |
2327 | ||
1da177e4 LT |
2328 | /** |
2329 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2330 | * @cpu: CPU which shall be re-evaluated | |
2331 | * | |
25985edc | 2332 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2333 | * at different times. |
2334 | */ | |
2335 | int cpufreq_update_policy(unsigned int cpu) | |
2336 | { | |
3a3e9e06 VK |
2337 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2338 | struct cpufreq_policy new_policy; | |
f1829e4a | 2339 | int ret; |
1da177e4 | 2340 | |
fefa8ff8 AP |
2341 | if (!policy) |
2342 | return -ENODEV; | |
1da177e4 | 2343 | |
ad7722da | 2344 | down_write(&policy->rwsem); |
1da177e4 | 2345 | |
2d06d8c4 | 2346 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2347 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2348 | new_policy.min = policy->user_policy.min; |
2349 | new_policy.max = policy->user_policy.max; | |
2350 | new_policy.policy = policy->user_policy.policy; | |
2351 | new_policy.governor = policy->user_policy.governor; | |
1da177e4 | 2352 | |
bb176f7d VK |
2353 | /* |
2354 | * BIOS might change freq behind our back | |
2355 | * -> ask driver for current freq and notify governors about a change | |
2356 | */ | |
2ed99e39 | 2357 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
3a3e9e06 | 2358 | new_policy.cur = cpufreq_driver->get(cpu); |
bd0fa9bb VK |
2359 | if (WARN_ON(!new_policy.cur)) { |
2360 | ret = -EIO; | |
fefa8ff8 | 2361 | goto unlock; |
bd0fa9bb VK |
2362 | } |
2363 | ||
3a3e9e06 | 2364 | if (!policy->cur) { |
e837f9b5 | 2365 | pr_debug("Driver did not initialize current freq\n"); |
3a3e9e06 | 2366 | policy->cur = new_policy.cur; |
a85f7bd3 | 2367 | } else { |
9c0ebcf7 | 2368 | if (policy->cur != new_policy.cur && has_target()) |
a1e1dc41 | 2369 | cpufreq_out_of_sync(policy, new_policy.cur); |
a85f7bd3 | 2370 | } |
0961dd0d TR |
2371 | } |
2372 | ||
037ce839 | 2373 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2374 | |
fefa8ff8 | 2375 | unlock: |
ad7722da | 2376 | up_write(&policy->rwsem); |
5a01f2e8 | 2377 | |
3a3e9e06 | 2378 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2379 | return ret; |
2380 | } | |
2381 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2382 | ||
2760984f | 2383 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2384 | unsigned long action, void *hcpu) |
2385 | { | |
2386 | unsigned int cpu = (unsigned long)hcpu; | |
8a25a2fd | 2387 | struct device *dev; |
c32b6b8e | 2388 | |
8a25a2fd KS |
2389 | dev = get_cpu_device(cpu); |
2390 | if (dev) { | |
5302c3fb | 2391 | switch (action & ~CPU_TASKS_FROZEN) { |
c32b6b8e | 2392 | case CPU_ONLINE: |
23faf0b7 | 2393 | cpufreq_add_dev(dev, NULL); |
c32b6b8e | 2394 | break; |
5302c3fb | 2395 | |
c32b6b8e | 2396 | case CPU_DOWN_PREPARE: |
96bbbe4a | 2397 | __cpufreq_remove_dev_prepare(dev, NULL); |
1aee40ac SB |
2398 | break; |
2399 | ||
2400 | case CPU_POST_DEAD: | |
96bbbe4a | 2401 | __cpufreq_remove_dev_finish(dev, NULL); |
c32b6b8e | 2402 | break; |
5302c3fb | 2403 | |
5a01f2e8 | 2404 | case CPU_DOWN_FAILED: |
23faf0b7 | 2405 | cpufreq_add_dev(dev, NULL); |
c32b6b8e AR |
2406 | break; |
2407 | } | |
2408 | } | |
2409 | return NOTIFY_OK; | |
2410 | } | |
2411 | ||
9c36f746 | 2412 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2413 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2414 | }; |
1da177e4 | 2415 | |
6f19efc0 LM |
2416 | /********************************************************************* |
2417 | * BOOST * | |
2418 | *********************************************************************/ | |
2419 | static int cpufreq_boost_set_sw(int state) | |
2420 | { | |
2421 | struct cpufreq_frequency_table *freq_table; | |
2422 | struct cpufreq_policy *policy; | |
2423 | int ret = -EINVAL; | |
2424 | ||
f963735a | 2425 | for_each_active_policy(policy) { |
6f19efc0 LM |
2426 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2427 | if (freq_table) { | |
2428 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2429 | freq_table); | |
2430 | if (ret) { | |
2431 | pr_err("%s: Policy frequency update failed\n", | |
2432 | __func__); | |
2433 | break; | |
2434 | } | |
2435 | policy->user_policy.max = policy->max; | |
2436 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2437 | } | |
2438 | } | |
2439 | ||
2440 | return ret; | |
2441 | } | |
2442 | ||
2443 | int cpufreq_boost_trigger_state(int state) | |
2444 | { | |
2445 | unsigned long flags; | |
2446 | int ret = 0; | |
2447 | ||
2448 | if (cpufreq_driver->boost_enabled == state) | |
2449 | return 0; | |
2450 | ||
2451 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2452 | cpufreq_driver->boost_enabled = state; | |
2453 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2454 | ||
2455 | ret = cpufreq_driver->set_boost(state); | |
2456 | if (ret) { | |
2457 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2458 | cpufreq_driver->boost_enabled = !state; | |
2459 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2460 | ||
e837f9b5 JP |
2461 | pr_err("%s: Cannot %s BOOST\n", |
2462 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2463 | } |
2464 | ||
2465 | return ret; | |
2466 | } | |
2467 | ||
2468 | int cpufreq_boost_supported(void) | |
2469 | { | |
2470 | if (likely(cpufreq_driver)) | |
2471 | return cpufreq_driver->boost_supported; | |
2472 | ||
2473 | return 0; | |
2474 | } | |
2475 | EXPORT_SYMBOL_GPL(cpufreq_boost_supported); | |
2476 | ||
2477 | int cpufreq_boost_enabled(void) | |
2478 | { | |
2479 | return cpufreq_driver->boost_enabled; | |
2480 | } | |
2481 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2482 | ||
1da177e4 LT |
2483 | /********************************************************************* |
2484 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2485 | *********************************************************************/ | |
2486 | ||
2487 | /** | |
2488 | * cpufreq_register_driver - register a CPU Frequency driver | |
2489 | * @driver_data: A struct cpufreq_driver containing the values# | |
2490 | * submitted by the CPU Frequency driver. | |
2491 | * | |
bb176f7d | 2492 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 2493 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 2494 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2495 | * |
2496 | */ | |
221dee28 | 2497 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2498 | { |
2499 | unsigned long flags; | |
2500 | int ret; | |
2501 | ||
a7b422cd KRW |
2502 | if (cpufreq_disabled()) |
2503 | return -ENODEV; | |
2504 | ||
1da177e4 | 2505 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2506 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2507 | driver_data->target) || |
2508 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2509 | driver_data->target)) || |
2510 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2511 | return -EINVAL; |
2512 | ||
2d06d8c4 | 2513 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2514 | |
0d1857a1 | 2515 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2516 | if (cpufreq_driver) { |
0d1857a1 | 2517 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4dea5806 | 2518 | return -EEXIST; |
1da177e4 | 2519 | } |
1c3d85dd | 2520 | cpufreq_driver = driver_data; |
0d1857a1 | 2521 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2522 | |
bc68b7df VK |
2523 | if (driver_data->setpolicy) |
2524 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2525 | ||
6f19efc0 LM |
2526 | if (cpufreq_boost_supported()) { |
2527 | /* | |
2528 | * Check if driver provides function to enable boost - | |
2529 | * if not, use cpufreq_boost_set_sw as default | |
2530 | */ | |
2531 | if (!cpufreq_driver->set_boost) | |
2532 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; | |
2533 | ||
2534 | ret = cpufreq_sysfs_create_file(&boost.attr); | |
2535 | if (ret) { | |
2536 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
e837f9b5 | 2537 | __func__); |
6f19efc0 LM |
2538 | goto err_null_driver; |
2539 | } | |
2540 | } | |
2541 | ||
8a25a2fd | 2542 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2543 | if (ret) |
6f19efc0 | 2544 | goto err_boost_unreg; |
1da177e4 | 2545 | |
ce1bcfe9 VK |
2546 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2547 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2548 | /* if all ->init() calls failed, unregister */ |
ce1bcfe9 VK |
2549 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2550 | driver_data->name); | |
2551 | goto err_if_unreg; | |
1da177e4 LT |
2552 | } |
2553 | ||
8f5bc2ab | 2554 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2555 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2556 | |
8f5bc2ab | 2557 | return 0; |
8a25a2fd KS |
2558 | err_if_unreg: |
2559 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 LM |
2560 | err_boost_unreg: |
2561 | if (cpufreq_boost_supported()) | |
2562 | cpufreq_sysfs_remove_file(&boost.attr); | |
8f5bc2ab | 2563 | err_null_driver: |
0d1857a1 | 2564 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2565 | cpufreq_driver = NULL; |
0d1857a1 | 2566 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4d34a67d | 2567 | return ret; |
1da177e4 LT |
2568 | } |
2569 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2570 | ||
1da177e4 LT |
2571 | /** |
2572 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2573 | * | |
bb176f7d | 2574 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2575 | * the right to do so, i.e. if you have succeeded in initialising before! |
2576 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2577 | * currently not initialised. | |
2578 | */ | |
221dee28 | 2579 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2580 | { |
2581 | unsigned long flags; | |
2582 | ||
1c3d85dd | 2583 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2584 | return -EINVAL; |
1da177e4 | 2585 | |
2d06d8c4 | 2586 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2587 | |
8a25a2fd | 2588 | subsys_interface_unregister(&cpufreq_interface); |
6f19efc0 LM |
2589 | if (cpufreq_boost_supported()) |
2590 | cpufreq_sysfs_remove_file(&boost.attr); | |
2591 | ||
65edc68c | 2592 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2593 | |
6eed9404 | 2594 | down_write(&cpufreq_rwsem); |
0d1857a1 | 2595 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2596 | |
1c3d85dd | 2597 | cpufreq_driver = NULL; |
6eed9404 | 2598 | |
0d1857a1 | 2599 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
6eed9404 | 2600 | up_write(&cpufreq_rwsem); |
1da177e4 LT |
2601 | |
2602 | return 0; | |
2603 | } | |
2604 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2605 | |
90de2a4a DA |
2606 | /* |
2607 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2608 | * or mutexes when secondary CPUs are halted. | |
2609 | */ | |
2610 | static struct syscore_ops cpufreq_syscore_ops = { | |
2611 | .shutdown = cpufreq_suspend, | |
2612 | }; | |
2613 | ||
5a01f2e8 VP |
2614 | static int __init cpufreq_core_init(void) |
2615 | { | |
a7b422cd KRW |
2616 | if (cpufreq_disabled()) |
2617 | return -ENODEV; | |
2618 | ||
2361be23 | 2619 | cpufreq_global_kobject = kobject_create(); |
8aa84ad8 TR |
2620 | BUG_ON(!cpufreq_global_kobject); |
2621 | ||
90de2a4a DA |
2622 | register_syscore_ops(&cpufreq_syscore_ops); |
2623 | ||
5a01f2e8 VP |
2624 | return 0; |
2625 | } | |
5a01f2e8 | 2626 | core_initcall(cpufreq_core_init); |