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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); |
8414809c | 104 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback); |
bb176f7d | 105 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
6f1e4efd | 106 | DEFINE_MUTEX(cpufreq_governor_lock); |
bb176f7d | 107 | |
084f3493 | 108 | /* This one keeps track of the previously set governor of a removed CPU */ |
e77b89f1 | 109 | static DEFINE_PER_CPU(char[CPUFREQ_NAME_LEN], cpufreq_cpu_governor); |
1da177e4 | 110 | |
2f0aea93 VK |
111 | /* Flag to suspend/resume CPUFreq governors */ |
112 | static bool cpufreq_suspended; | |
1da177e4 | 113 | |
9c0ebcf7 VK |
114 | static inline bool has_target(void) |
115 | { | |
116 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
117 | } | |
118 | ||
6eed9404 VK |
119 | /* |
120 | * rwsem to guarantee that cpufreq driver module doesn't unload during critical | |
121 | * sections | |
122 | */ | |
123 | static DECLARE_RWSEM(cpufreq_rwsem); | |
124 | ||
1da177e4 | 125 | /* internal prototypes */ |
29464f28 DJ |
126 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
127 | unsigned int event); | |
d92d50a4 | 128 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
65f27f38 | 129 | static void handle_update(struct work_struct *work); |
1da177e4 LT |
130 | |
131 | /** | |
32ee8c3e DJ |
132 | * Two notifier lists: the "policy" list is involved in the |
133 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
134 | * "transition" list for kernel code that needs to handle |
135 | * changes to devices when the CPU clock speed changes. | |
136 | * The mutex locks both lists. | |
137 | */ | |
e041c683 | 138 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 139 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 140 | |
74212ca4 | 141 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
142 | static int __init init_cpufreq_transition_notifier_list(void) |
143 | { | |
144 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 145 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
146 | return 0; |
147 | } | |
b3438f82 | 148 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 149 | |
a7b422cd | 150 | static int off __read_mostly; |
da584455 | 151 | static int cpufreq_disabled(void) |
a7b422cd KRW |
152 | { |
153 | return off; | |
154 | } | |
155 | void disable_cpufreq(void) | |
156 | { | |
157 | off = 1; | |
158 | } | |
29464f28 | 159 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 160 | |
4d5dcc42 VK |
161 | bool have_governor_per_policy(void) |
162 | { | |
0b981e70 | 163 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 164 | } |
3f869d6d | 165 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 166 | |
944e9a03 VK |
167 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
168 | { | |
169 | if (have_governor_per_policy()) | |
170 | return &policy->kobj; | |
171 | else | |
172 | return cpufreq_global_kobject; | |
173 | } | |
174 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
175 | ||
72a4ce34 VK |
176 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
177 | { | |
178 | u64 idle_time; | |
179 | u64 cur_wall_time; | |
180 | u64 busy_time; | |
181 | ||
182 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
183 | ||
184 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
185 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
186 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
187 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
188 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
189 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
190 | ||
191 | idle_time = cur_wall_time - busy_time; | |
192 | if (wall) | |
193 | *wall = cputime_to_usecs(cur_wall_time); | |
194 | ||
195 | return cputime_to_usecs(idle_time); | |
196 | } | |
197 | ||
198 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
199 | { | |
200 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
201 | ||
202 | if (idle_time == -1ULL) | |
203 | return get_cpu_idle_time_jiffy(cpu, wall); | |
204 | else if (!io_busy) | |
205 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
206 | ||
207 | return idle_time; | |
208 | } | |
209 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
210 | ||
70e9e778 VK |
211 | /* |
212 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
213 | * drivers of SMP systems. It will do following: | |
214 | * - validate & show freq table passed | |
215 | * - set policies transition latency | |
216 | * - policy->cpus with all possible CPUs | |
217 | */ | |
218 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
219 | struct cpufreq_frequency_table *table, | |
220 | unsigned int transition_latency) | |
221 | { | |
222 | int ret; | |
223 | ||
224 | ret = cpufreq_table_validate_and_show(policy, table); | |
225 | if (ret) { | |
226 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
227 | return ret; | |
228 | } | |
229 | ||
230 | policy->cpuinfo.transition_latency = transition_latency; | |
231 | ||
232 | /* | |
233 | * The driver only supports the SMP configuartion where all processors | |
234 | * share the clock and voltage and clock. | |
235 | */ | |
236 | cpumask_setall(policy->cpus); | |
237 | ||
238 | return 0; | |
239 | } | |
240 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
241 | ||
988bed09 VK |
242 | /* Only for cpufreq core internal use */ |
243 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) | |
652ed95d VK |
244 | { |
245 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
246 | ||
988bed09 VK |
247 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
248 | } | |
249 | ||
250 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
251 | { | |
252 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
253 | ||
652ed95d | 254 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
255 | pr_err("%s: No %s associated to cpu: %d\n", |
256 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
257 | return 0; |
258 | } | |
259 | ||
260 | return clk_get_rate(policy->clk) / 1000; | |
261 | } | |
262 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
263 | ||
50e9c852 VK |
264 | /** |
265 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
266 | * | |
267 | * @cpu: cpu to find policy for. | |
268 | * | |
269 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
270 | * It also increments the kobject reference count to mark it busy and so would | |
271 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
272 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
273 | * freed as that depends on the kobj count. | |
274 | * | |
275 | * It also takes a read-lock of 'cpufreq_rwsem' and doesn't put it back if a | |
276 | * valid policy is found. This is done to make sure the driver doesn't get | |
277 | * unregistered while the policy is being used. | |
278 | * | |
279 | * Return: A valid policy on success, otherwise NULL on failure. | |
280 | */ | |
6eed9404 | 281 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 282 | { |
6eed9404 | 283 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
284 | unsigned long flags; |
285 | ||
1b947c90 | 286 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
287 | return NULL; |
288 | ||
289 | if (!down_read_trylock(&cpufreq_rwsem)) | |
290 | return NULL; | |
1da177e4 LT |
291 | |
292 | /* get the cpufreq driver */ | |
1c3d85dd | 293 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 294 | |
6eed9404 VK |
295 | if (cpufreq_driver) { |
296 | /* get the CPU */ | |
988bed09 | 297 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
298 | if (policy) |
299 | kobject_get(&policy->kobj); | |
300 | } | |
1da177e4 | 301 | |
6eed9404 | 302 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 303 | |
3a3e9e06 | 304 | if (!policy) |
6eed9404 | 305 | up_read(&cpufreq_rwsem); |
1da177e4 | 306 | |
3a3e9e06 | 307 | return policy; |
a9144436 | 308 | } |
1da177e4 LT |
309 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
310 | ||
50e9c852 VK |
311 | /** |
312 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
313 | * | |
314 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
315 | * | |
316 | * This decrements the kobject reference count incremented earlier by calling | |
317 | * cpufreq_cpu_get(). | |
318 | * | |
319 | * It also drops the read-lock of 'cpufreq_rwsem' taken at cpufreq_cpu_get(). | |
320 | */ | |
3a3e9e06 | 321 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 322 | { |
6eed9404 VK |
323 | kobject_put(&policy->kobj); |
324 | up_read(&cpufreq_rwsem); | |
1da177e4 LT |
325 | } |
326 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
327 | ||
1da177e4 LT |
328 | /********************************************************************* |
329 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
330 | *********************************************************************/ | |
331 | ||
332 | /** | |
333 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
334 | * | |
335 | * This function alters the system "loops_per_jiffy" for the clock | |
336 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 337 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
338 | * per-CPU loops_per_jiffy value wherever possible. |
339 | */ | |
858119e1 | 340 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 341 | { |
39c132ee VK |
342 | #ifndef CONFIG_SMP |
343 | static unsigned long l_p_j_ref; | |
344 | static unsigned int l_p_j_ref_freq; | |
345 | ||
1da177e4 LT |
346 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
347 | return; | |
348 | ||
349 | if (!l_p_j_ref_freq) { | |
350 | l_p_j_ref = loops_per_jiffy; | |
351 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
352 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
353 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 354 | } |
0b443ead | 355 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
356 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
357 | ci->new); | |
e837f9b5 JP |
358 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
359 | loops_per_jiffy, ci->new); | |
1da177e4 | 360 | } |
1da177e4 | 361 | #endif |
39c132ee | 362 | } |
1da177e4 | 363 | |
0956df9c | 364 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 365 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
366 | { |
367 | BUG_ON(irqs_disabled()); | |
368 | ||
d5aaffa9 DB |
369 | if (cpufreq_disabled()) |
370 | return; | |
371 | ||
1c3d85dd | 372 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 373 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 374 | state, freqs->new); |
1da177e4 | 375 | |
1da177e4 | 376 | switch (state) { |
e4472cb3 | 377 | |
1da177e4 | 378 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 379 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
380 | * which is not equal to what the cpufreq core thinks is |
381 | * "old frequency". | |
1da177e4 | 382 | */ |
1c3d85dd | 383 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
384 | if ((policy) && (policy->cpu == freqs->cpu) && |
385 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
386 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
387 | freqs->old, policy->cur); | |
e4472cb3 | 388 | freqs->old = policy->cur; |
1da177e4 LT |
389 | } |
390 | } | |
b4dfdbb3 | 391 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 392 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
393 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
394 | break; | |
e4472cb3 | 395 | |
1da177e4 LT |
396 | case CPUFREQ_POSTCHANGE: |
397 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
398 | pr_debug("FREQ: %lu - CPU: %lu\n", |
399 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 400 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 401 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 402 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
403 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
404 | policy->cur = freqs->new; | |
1da177e4 LT |
405 | break; |
406 | } | |
1da177e4 | 407 | } |
bb176f7d | 408 | |
b43a7ffb VK |
409 | /** |
410 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
411 | * on frequency transition. | |
412 | * | |
413 | * This function calls the transition notifiers and the "adjust_jiffies" | |
414 | * function. It is called twice on all CPU frequency changes that have | |
415 | * external effects. | |
416 | */ | |
236a9800 | 417 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
418 | struct cpufreq_freqs *freqs, unsigned int state) |
419 | { | |
420 | for_each_cpu(freqs->cpu, policy->cpus) | |
421 | __cpufreq_notify_transition(policy, freqs, state); | |
422 | } | |
1da177e4 | 423 | |
f7ba3b41 | 424 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 425 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
426 | struct cpufreq_freqs *freqs, int transition_failed) |
427 | { | |
428 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
429 | if (!transition_failed) | |
430 | return; | |
431 | ||
432 | swap(freqs->old, freqs->new); | |
433 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
434 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
435 | } | |
f7ba3b41 | 436 | |
12478cf0 SB |
437 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
438 | struct cpufreq_freqs *freqs) | |
439 | { | |
ca654dc3 SB |
440 | |
441 | /* | |
442 | * Catch double invocations of _begin() which lead to self-deadlock. | |
443 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
444 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
445 | * double invocations are very low. Moreover, there are scenarios | |
446 | * where these checks can emit false-positive warnings in these | |
447 | * drivers; so we avoid that by skipping them altogether. | |
448 | */ | |
449 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
450 | && current == policy->transition_task); | |
451 | ||
12478cf0 SB |
452 | wait: |
453 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
454 | ||
455 | spin_lock(&policy->transition_lock); | |
456 | ||
457 | if (unlikely(policy->transition_ongoing)) { | |
458 | spin_unlock(&policy->transition_lock); | |
459 | goto wait; | |
460 | } | |
461 | ||
462 | policy->transition_ongoing = true; | |
ca654dc3 | 463 | policy->transition_task = current; |
12478cf0 SB |
464 | |
465 | spin_unlock(&policy->transition_lock); | |
466 | ||
467 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
468 | } | |
469 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
470 | ||
471 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
472 | struct cpufreq_freqs *freqs, int transition_failed) | |
473 | { | |
474 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
475 | return; | |
476 | ||
477 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
478 | ||
479 | policy->transition_ongoing = false; | |
ca654dc3 | 480 | policy->transition_task = NULL; |
12478cf0 SB |
481 | |
482 | wake_up(&policy->transition_wait); | |
483 | } | |
484 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
485 | ||
1da177e4 | 486 | |
1da177e4 LT |
487 | /********************************************************************* |
488 | * SYSFS INTERFACE * | |
489 | *********************************************************************/ | |
8a5c74a1 | 490 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
491 | struct attribute *attr, char *buf) |
492 | { | |
493 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
494 | } | |
495 | ||
496 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
497 | const char *buf, size_t count) | |
498 | { | |
499 | int ret, enable; | |
500 | ||
501 | ret = sscanf(buf, "%d", &enable); | |
502 | if (ret != 1 || enable < 0 || enable > 1) | |
503 | return -EINVAL; | |
504 | ||
505 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
506 | pr_err("%s: Cannot %s BOOST!\n", |
507 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
508 | return -EINVAL; |
509 | } | |
510 | ||
e837f9b5 JP |
511 | pr_debug("%s: cpufreq BOOST %s\n", |
512 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
513 | |
514 | return count; | |
515 | } | |
516 | define_one_global_rw(boost); | |
1da177e4 | 517 | |
42f91fa1 | 518 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
519 | { |
520 | struct cpufreq_governor *t; | |
521 | ||
f7b27061 | 522 | for_each_governor(t) |
7c4f4539 | 523 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
524 | return t; |
525 | ||
526 | return NULL; | |
527 | } | |
528 | ||
1da177e4 LT |
529 | /** |
530 | * cpufreq_parse_governor - parse a governor string | |
531 | */ | |
905d77cd | 532 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
533 | struct cpufreq_governor **governor) |
534 | { | |
3bcb09a3 | 535 | int err = -EINVAL; |
1c3d85dd RW |
536 | |
537 | if (!cpufreq_driver) | |
3bcb09a3 JF |
538 | goto out; |
539 | ||
1c3d85dd | 540 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 541 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 542 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 543 | err = 0; |
7c4f4539 | 544 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 545 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 546 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 547 | err = 0; |
1da177e4 | 548 | } |
2e1cc3a5 | 549 | } else { |
1da177e4 | 550 | struct cpufreq_governor *t; |
3bcb09a3 | 551 | |
3fc54d37 | 552 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 553 | |
42f91fa1 | 554 | t = find_governor(str_governor); |
3bcb09a3 | 555 | |
ea714970 | 556 | if (t == NULL) { |
1a8e1463 | 557 | int ret; |
ea714970 | 558 | |
1a8e1463 KC |
559 | mutex_unlock(&cpufreq_governor_mutex); |
560 | ret = request_module("cpufreq_%s", str_governor); | |
561 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 562 | |
1a8e1463 | 563 | if (ret == 0) |
42f91fa1 | 564 | t = find_governor(str_governor); |
ea714970 JF |
565 | } |
566 | ||
3bcb09a3 JF |
567 | if (t != NULL) { |
568 | *governor = t; | |
569 | err = 0; | |
1da177e4 | 570 | } |
3bcb09a3 | 571 | |
3fc54d37 | 572 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 573 | } |
29464f28 | 574 | out: |
3bcb09a3 | 575 | return err; |
1da177e4 | 576 | } |
1da177e4 | 577 | |
1da177e4 | 578 | /** |
e08f5f5b GS |
579 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
580 | * print out cpufreq information | |
1da177e4 LT |
581 | * |
582 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
583 | * "unsigned int". | |
584 | */ | |
585 | ||
32ee8c3e DJ |
586 | #define show_one(file_name, object) \ |
587 | static ssize_t show_##file_name \ | |
905d77cd | 588 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 589 | { \ |
29464f28 | 590 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
591 | } |
592 | ||
593 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
594 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 595 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
596 | show_one(scaling_min_freq, min); |
597 | show_one(scaling_max_freq, max); | |
c034b02e | 598 | |
09347b29 | 599 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
600 | { |
601 | ssize_t ret; | |
602 | ||
603 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
604 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
605 | else | |
606 | ret = sprintf(buf, "%u\n", policy->cur); | |
607 | return ret; | |
608 | } | |
1da177e4 | 609 | |
037ce839 | 610 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 611 | struct cpufreq_policy *new_policy); |
7970e08b | 612 | |
1da177e4 LT |
613 | /** |
614 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
615 | */ | |
616 | #define store_one(file_name, object) \ | |
617 | static ssize_t store_##file_name \ | |
905d77cd | 618 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 619 | { \ |
619c144c | 620 | int ret, temp; \ |
1da177e4 LT |
621 | struct cpufreq_policy new_policy; \ |
622 | \ | |
623 | ret = cpufreq_get_policy(&new_policy, policy->cpu); \ | |
624 | if (ret) \ | |
625 | return -EINVAL; \ | |
626 | \ | |
29464f28 | 627 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
628 | if (ret != 1) \ |
629 | return -EINVAL; \ | |
630 | \ | |
619c144c | 631 | temp = new_policy.object; \ |
037ce839 | 632 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
633 | if (!ret) \ |
634 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
635 | \ |
636 | return ret ? ret : count; \ | |
637 | } | |
638 | ||
29464f28 DJ |
639 | store_one(scaling_min_freq, min); |
640 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
641 | |
642 | /** | |
643 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
644 | */ | |
905d77cd DJ |
645 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
646 | char *buf) | |
1da177e4 | 647 | { |
d92d50a4 | 648 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
649 | if (!cur_freq) |
650 | return sprintf(buf, "<unknown>"); | |
651 | return sprintf(buf, "%u\n", cur_freq); | |
652 | } | |
653 | ||
1da177e4 LT |
654 | /** |
655 | * show_scaling_governor - show the current policy for the specified CPU | |
656 | */ | |
905d77cd | 657 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 658 | { |
29464f28 | 659 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
660 | return sprintf(buf, "powersave\n"); |
661 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
662 | return sprintf(buf, "performance\n"); | |
663 | else if (policy->governor) | |
4b972f0b | 664 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 665 | policy->governor->name); |
1da177e4 LT |
666 | return -EINVAL; |
667 | } | |
668 | ||
1da177e4 LT |
669 | /** |
670 | * store_scaling_governor - store policy for the specified CPU | |
671 | */ | |
905d77cd DJ |
672 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
673 | const char *buf, size_t count) | |
1da177e4 | 674 | { |
5136fa56 | 675 | int ret; |
1da177e4 LT |
676 | char str_governor[16]; |
677 | struct cpufreq_policy new_policy; | |
678 | ||
679 | ret = cpufreq_get_policy(&new_policy, policy->cpu); | |
680 | if (ret) | |
681 | return ret; | |
682 | ||
29464f28 | 683 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
684 | if (ret != 1) |
685 | return -EINVAL; | |
686 | ||
e08f5f5b GS |
687 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
688 | &new_policy.governor)) | |
1da177e4 LT |
689 | return -EINVAL; |
690 | ||
037ce839 | 691 | ret = cpufreq_set_policy(policy, &new_policy); |
7970e08b TR |
692 | |
693 | policy->user_policy.policy = policy->policy; | |
694 | policy->user_policy.governor = policy->governor; | |
7970e08b | 695 | |
e08f5f5b GS |
696 | if (ret) |
697 | return ret; | |
698 | else | |
699 | return count; | |
1da177e4 LT |
700 | } |
701 | ||
702 | /** | |
703 | * show_scaling_driver - show the cpufreq driver currently loaded | |
704 | */ | |
905d77cd | 705 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 706 | { |
1c3d85dd | 707 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
708 | } |
709 | ||
710 | /** | |
711 | * show_scaling_available_governors - show the available CPUfreq governors | |
712 | */ | |
905d77cd DJ |
713 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
714 | char *buf) | |
1da177e4 LT |
715 | { |
716 | ssize_t i = 0; | |
717 | struct cpufreq_governor *t; | |
718 | ||
9c0ebcf7 | 719 | if (!has_target()) { |
1da177e4 LT |
720 | i += sprintf(buf, "performance powersave"); |
721 | goto out; | |
722 | } | |
723 | ||
f7b27061 | 724 | for_each_governor(t) { |
29464f28 DJ |
725 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
726 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 727 | goto out; |
4b972f0b | 728 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 729 | } |
7d5e350f | 730 | out: |
1da177e4 LT |
731 | i += sprintf(&buf[i], "\n"); |
732 | return i; | |
733 | } | |
e8628dd0 | 734 | |
f4fd3797 | 735 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
736 | { |
737 | ssize_t i = 0; | |
738 | unsigned int cpu; | |
739 | ||
835481d9 | 740 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
741 | if (i) |
742 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
743 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
744 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 745 | break; |
1da177e4 LT |
746 | } |
747 | i += sprintf(&buf[i], "\n"); | |
748 | return i; | |
749 | } | |
f4fd3797 | 750 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 751 | |
e8628dd0 DW |
752 | /** |
753 | * show_related_cpus - show the CPUs affected by each transition even if | |
754 | * hw coordination is in use | |
755 | */ | |
756 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
757 | { | |
f4fd3797 | 758 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
759 | } |
760 | ||
761 | /** | |
762 | * show_affected_cpus - show the CPUs affected by each transition | |
763 | */ | |
764 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
765 | { | |
f4fd3797 | 766 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
767 | } |
768 | ||
9e76988e | 769 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 770 | const char *buf, size_t count) |
9e76988e VP |
771 | { |
772 | unsigned int freq = 0; | |
773 | unsigned int ret; | |
774 | ||
879000f9 | 775 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
776 | return -EINVAL; |
777 | ||
778 | ret = sscanf(buf, "%u", &freq); | |
779 | if (ret != 1) | |
780 | return -EINVAL; | |
781 | ||
782 | policy->governor->store_setspeed(policy, freq); | |
783 | ||
784 | return count; | |
785 | } | |
786 | ||
787 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
788 | { | |
879000f9 | 789 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
790 | return sprintf(buf, "<unsupported>\n"); |
791 | ||
792 | return policy->governor->show_setspeed(policy, buf); | |
793 | } | |
1da177e4 | 794 | |
e2f74f35 | 795 | /** |
8bf1ac72 | 796 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
797 | */ |
798 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
799 | { | |
800 | unsigned int limit; | |
801 | int ret; | |
1c3d85dd RW |
802 | if (cpufreq_driver->bios_limit) { |
803 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
804 | if (!ret) |
805 | return sprintf(buf, "%u\n", limit); | |
806 | } | |
807 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
808 | } | |
809 | ||
6dad2a29 BP |
810 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
811 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
812 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
813 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
814 | cpufreq_freq_attr_ro(scaling_available_governors); | |
815 | cpufreq_freq_attr_ro(scaling_driver); | |
816 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
817 | cpufreq_freq_attr_ro(bios_limit); | |
818 | cpufreq_freq_attr_ro(related_cpus); | |
819 | cpufreq_freq_attr_ro(affected_cpus); | |
820 | cpufreq_freq_attr_rw(scaling_min_freq); | |
821 | cpufreq_freq_attr_rw(scaling_max_freq); | |
822 | cpufreq_freq_attr_rw(scaling_governor); | |
823 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 824 | |
905d77cd | 825 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
826 | &cpuinfo_min_freq.attr, |
827 | &cpuinfo_max_freq.attr, | |
ed129784 | 828 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
829 | &scaling_min_freq.attr, |
830 | &scaling_max_freq.attr, | |
831 | &affected_cpus.attr, | |
e8628dd0 | 832 | &related_cpus.attr, |
1da177e4 LT |
833 | &scaling_governor.attr, |
834 | &scaling_driver.attr, | |
835 | &scaling_available_governors.attr, | |
9e76988e | 836 | &scaling_setspeed.attr, |
1da177e4 LT |
837 | NULL |
838 | }; | |
839 | ||
29464f28 DJ |
840 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
841 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 842 | |
29464f28 | 843 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 844 | { |
905d77cd DJ |
845 | struct cpufreq_policy *policy = to_policy(kobj); |
846 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 847 | ssize_t ret; |
6eed9404 VK |
848 | |
849 | if (!down_read_trylock(&cpufreq_rwsem)) | |
1b750e3b | 850 | return -EINVAL; |
5a01f2e8 | 851 | |
ad7722da | 852 | down_read(&policy->rwsem); |
5a01f2e8 | 853 | |
e08f5f5b GS |
854 | if (fattr->show) |
855 | ret = fattr->show(policy, buf); | |
856 | else | |
857 | ret = -EIO; | |
858 | ||
ad7722da | 859 | up_read(&policy->rwsem); |
6eed9404 | 860 | up_read(&cpufreq_rwsem); |
1b750e3b | 861 | |
1da177e4 LT |
862 | return ret; |
863 | } | |
864 | ||
905d77cd DJ |
865 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
866 | const char *buf, size_t count) | |
1da177e4 | 867 | { |
905d77cd DJ |
868 | struct cpufreq_policy *policy = to_policy(kobj); |
869 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 870 | ssize_t ret = -EINVAL; |
6eed9404 | 871 | |
4f750c93 SB |
872 | get_online_cpus(); |
873 | ||
874 | if (!cpu_online(policy->cpu)) | |
875 | goto unlock; | |
876 | ||
6eed9404 | 877 | if (!down_read_trylock(&cpufreq_rwsem)) |
4f750c93 | 878 | goto unlock; |
5a01f2e8 | 879 | |
ad7722da | 880 | down_write(&policy->rwsem); |
5a01f2e8 | 881 | |
e08f5f5b GS |
882 | if (fattr->store) |
883 | ret = fattr->store(policy, buf, count); | |
884 | else | |
885 | ret = -EIO; | |
886 | ||
ad7722da | 887 | up_write(&policy->rwsem); |
6eed9404 | 888 | |
6eed9404 | 889 | up_read(&cpufreq_rwsem); |
4f750c93 SB |
890 | unlock: |
891 | put_online_cpus(); | |
892 | ||
1da177e4 LT |
893 | return ret; |
894 | } | |
895 | ||
905d77cd | 896 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 897 | { |
905d77cd | 898 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 899 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
900 | complete(&policy->kobj_unregister); |
901 | } | |
902 | ||
52cf25d0 | 903 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
904 | .show = show, |
905 | .store = store, | |
906 | }; | |
907 | ||
908 | static struct kobj_type ktype_cpufreq = { | |
909 | .sysfs_ops = &sysfs_ops, | |
910 | .default_attrs = default_attrs, | |
911 | .release = cpufreq_sysfs_release, | |
912 | }; | |
913 | ||
2361be23 VK |
914 | struct kobject *cpufreq_global_kobject; |
915 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
916 | ||
917 | static int cpufreq_global_kobject_usage; | |
918 | ||
919 | int cpufreq_get_global_kobject(void) | |
920 | { | |
921 | if (!cpufreq_global_kobject_usage++) | |
922 | return kobject_add(cpufreq_global_kobject, | |
923 | &cpu_subsys.dev_root->kobj, "%s", "cpufreq"); | |
924 | ||
925 | return 0; | |
926 | } | |
927 | EXPORT_SYMBOL(cpufreq_get_global_kobject); | |
928 | ||
929 | void cpufreq_put_global_kobject(void) | |
930 | { | |
931 | if (!--cpufreq_global_kobject_usage) | |
932 | kobject_del(cpufreq_global_kobject); | |
933 | } | |
934 | EXPORT_SYMBOL(cpufreq_put_global_kobject); | |
935 | ||
936 | int cpufreq_sysfs_create_file(const struct attribute *attr) | |
937 | { | |
938 | int ret = cpufreq_get_global_kobject(); | |
939 | ||
940 | if (!ret) { | |
941 | ret = sysfs_create_file(cpufreq_global_kobject, attr); | |
942 | if (ret) | |
943 | cpufreq_put_global_kobject(); | |
944 | } | |
945 | ||
946 | return ret; | |
947 | } | |
948 | EXPORT_SYMBOL(cpufreq_sysfs_create_file); | |
949 | ||
950 | void cpufreq_sysfs_remove_file(const struct attribute *attr) | |
951 | { | |
952 | sysfs_remove_file(cpufreq_global_kobject, attr); | |
953 | cpufreq_put_global_kobject(); | |
954 | } | |
955 | EXPORT_SYMBOL(cpufreq_sysfs_remove_file); | |
956 | ||
19d6f7ec | 957 | /* symlink affected CPUs */ |
308b60e7 | 958 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
959 | { |
960 | unsigned int j; | |
961 | int ret = 0; | |
962 | ||
963 | for_each_cpu(j, policy->cpus) { | |
8a25a2fd | 964 | struct device *cpu_dev; |
19d6f7ec | 965 | |
308b60e7 | 966 | if (j == policy->cpu) |
19d6f7ec | 967 | continue; |
19d6f7ec | 968 | |
e8fdde10 | 969 | pr_debug("Adding link for CPU: %u\n", j); |
8a25a2fd KS |
970 | cpu_dev = get_cpu_device(j); |
971 | ret = sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
19d6f7ec | 972 | "cpufreq"); |
71c3461e RW |
973 | if (ret) |
974 | break; | |
19d6f7ec DJ |
975 | } |
976 | return ret; | |
977 | } | |
978 | ||
308b60e7 | 979 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy, |
8a25a2fd | 980 | struct device *dev) |
909a694e DJ |
981 | { |
982 | struct freq_attr **drv_attr; | |
909a694e | 983 | int ret = 0; |
909a694e | 984 | |
909a694e | 985 | /* set up files for this cpu device */ |
1c3d85dd | 986 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 987 | while (drv_attr && *drv_attr) { |
909a694e DJ |
988 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
989 | if (ret) | |
6d4e81ed | 990 | return ret; |
909a694e DJ |
991 | drv_attr++; |
992 | } | |
1c3d85dd | 993 | if (cpufreq_driver->get) { |
909a694e DJ |
994 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
995 | if (ret) | |
6d4e81ed | 996 | return ret; |
909a694e | 997 | } |
c034b02e DB |
998 | |
999 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
1000 | if (ret) | |
6d4e81ed | 1001 | return ret; |
c034b02e | 1002 | |
1c3d85dd | 1003 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
1004 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
1005 | if (ret) | |
6d4e81ed | 1006 | return ret; |
e2f74f35 | 1007 | } |
909a694e | 1008 | |
6d4e81ed | 1009 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
1010 | } |
1011 | ||
1012 | static void cpufreq_init_policy(struct cpufreq_policy *policy) | |
1013 | { | |
6e2c89d1 | 1014 | struct cpufreq_governor *gov = NULL; |
e18f1682 SB |
1015 | struct cpufreq_policy new_policy; |
1016 | int ret = 0; | |
1017 | ||
d5b73cd8 | 1018 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 1019 | |
6e2c89d1 | 1020 | /* Update governor of new_policy to the governor used before hotplug */ |
42f91fa1 | 1021 | gov = find_governor(per_cpu(cpufreq_cpu_governor, policy->cpu)); |
6e2c89d1 | 1022 | if (gov) |
1023 | pr_debug("Restoring governor %s for cpu %d\n", | |
1024 | policy->governor->name, policy->cpu); | |
1025 | else | |
1026 | gov = CPUFREQ_DEFAULT_GOVERNOR; | |
1027 | ||
1028 | new_policy.governor = gov; | |
1029 | ||
a27a9ab7 JB |
1030 | /* Use the default policy if its valid. */ |
1031 | if (cpufreq_driver->setpolicy) | |
6e2c89d1 | 1032 | cpufreq_parse_governor(gov->name, &new_policy.policy, NULL); |
ecf7e461 DJ |
1033 | |
1034 | /* set default policy */ | |
037ce839 | 1035 | ret = cpufreq_set_policy(policy, &new_policy); |
ecf7e461 | 1036 | if (ret) { |
2d06d8c4 | 1037 | pr_debug("setting policy failed\n"); |
1c3d85dd RW |
1038 | if (cpufreq_driver->exit) |
1039 | cpufreq_driver->exit(policy); | |
ecf7e461 | 1040 | } |
909a694e DJ |
1041 | } |
1042 | ||
d8d3b471 | 1043 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, |
42f921a6 | 1044 | unsigned int cpu, struct device *dev) |
fcf80582 | 1045 | { |
9c0ebcf7 | 1046 | int ret = 0; |
fcf80582 | 1047 | |
bb29ae15 VK |
1048 | /* Has this CPU been taken care of already? */ |
1049 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
1050 | return 0; | |
1051 | ||
9c0ebcf7 | 1052 | if (has_target()) { |
3de9bdeb VK |
1053 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1054 | if (ret) { | |
1055 | pr_err("%s: Failed to stop governor\n", __func__); | |
1056 | return ret; | |
1057 | } | |
1058 | } | |
fcf80582 | 1059 | |
ad7722da | 1060 | down_write(&policy->rwsem); |
fcf80582 | 1061 | cpumask_set_cpu(cpu, policy->cpus); |
ad7722da | 1062 | up_write(&policy->rwsem); |
2eaa3e2d | 1063 | |
9c0ebcf7 | 1064 | if (has_target()) { |
e5c87b76 SK |
1065 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); |
1066 | if (!ret) | |
1067 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1068 | ||
1069 | if (ret) { | |
3de9bdeb VK |
1070 | pr_err("%s: Failed to start governor\n", __func__); |
1071 | return ret; | |
1072 | } | |
820c6ca2 | 1073 | } |
fcf80582 | 1074 | |
42f921a6 | 1075 | return sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); |
fcf80582 | 1076 | } |
1da177e4 | 1077 | |
8414809c SB |
1078 | static struct cpufreq_policy *cpufreq_policy_restore(unsigned int cpu) |
1079 | { | |
1080 | struct cpufreq_policy *policy; | |
1081 | unsigned long flags; | |
1082 | ||
44871c9c | 1083 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
8414809c SB |
1084 | |
1085 | policy = per_cpu(cpufreq_cpu_data_fallback, cpu); | |
1086 | ||
44871c9c | 1087 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
8414809c | 1088 | |
09712f55 GU |
1089 | if (policy) |
1090 | policy->governor = NULL; | |
6e2c89d1 | 1091 | |
8414809c SB |
1092 | return policy; |
1093 | } | |
1094 | ||
e9698cc5 SB |
1095 | static struct cpufreq_policy *cpufreq_policy_alloc(void) |
1096 | { | |
1097 | struct cpufreq_policy *policy; | |
1098 | ||
1099 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); | |
1100 | if (!policy) | |
1101 | return NULL; | |
1102 | ||
1103 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1104 | goto err_free_policy; | |
1105 | ||
1106 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1107 | goto err_free_cpumask; | |
1108 | ||
c88a1f8b | 1109 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1110 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1111 | spin_lock_init(&policy->transition_lock); |
1112 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1113 | init_completion(&policy->kobj_unregister); |
1114 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1115 | |
e9698cc5 SB |
1116 | return policy; |
1117 | ||
1118 | err_free_cpumask: | |
1119 | free_cpumask_var(policy->cpus); | |
1120 | err_free_policy: | |
1121 | kfree(policy); | |
1122 | ||
1123 | return NULL; | |
1124 | } | |
1125 | ||
42f921a6 VK |
1126 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) |
1127 | { | |
1128 | struct kobject *kobj; | |
1129 | struct completion *cmp; | |
1130 | ||
fcd7af91 VK |
1131 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1132 | CPUFREQ_REMOVE_POLICY, policy); | |
1133 | ||
42f921a6 VK |
1134 | down_read(&policy->rwsem); |
1135 | kobj = &policy->kobj; | |
1136 | cmp = &policy->kobj_unregister; | |
1137 | up_read(&policy->rwsem); | |
1138 | kobject_put(kobj); | |
1139 | ||
1140 | /* | |
1141 | * We need to make sure that the underlying kobj is | |
1142 | * actually not referenced anymore by anybody before we | |
1143 | * proceed with unloading. | |
1144 | */ | |
1145 | pr_debug("waiting for dropping of refcount\n"); | |
1146 | wait_for_completion(cmp); | |
1147 | pr_debug("wait complete\n"); | |
1148 | } | |
1149 | ||
e9698cc5 SB |
1150 | static void cpufreq_policy_free(struct cpufreq_policy *policy) |
1151 | { | |
988bed09 VK |
1152 | unsigned long flags; |
1153 | int cpu; | |
1154 | ||
1155 | /* Remove policy from list */ | |
1156 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1157 | list_del(&policy->policy_list); | |
1158 | ||
1159 | for_each_cpu(cpu, policy->related_cpus) | |
1160 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1161 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1162 | ||
e9698cc5 SB |
1163 | free_cpumask_var(policy->related_cpus); |
1164 | free_cpumask_var(policy->cpus); | |
1165 | kfree(policy); | |
1166 | } | |
1167 | ||
1bfb425b VK |
1168 | static int update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu, |
1169 | struct device *cpu_dev) | |
0d66b91e | 1170 | { |
1bfb425b VK |
1171 | int ret; |
1172 | ||
99ec899e | 1173 | if (WARN_ON(cpu == policy->cpu)) |
1bfb425b VK |
1174 | return 0; |
1175 | ||
1176 | /* Move kobject to the new policy->cpu */ | |
1177 | ret = kobject_move(&policy->kobj, &cpu_dev->kobj); | |
1178 | if (ret) { | |
1179 | pr_err("%s: Failed to move kobj: %d\n", __func__, ret); | |
1180 | return ret; | |
1181 | } | |
cb38ed5c | 1182 | |
ad7722da | 1183 | down_write(&policy->rwsem); |
0d66b91e | 1184 | policy->cpu = cpu; |
ad7722da | 1185 | up_write(&policy->rwsem); |
8efd5765 | 1186 | |
1bfb425b | 1187 | return 0; |
0d66b91e SB |
1188 | } |
1189 | ||
23faf0b7 VK |
1190 | /** |
1191 | * cpufreq_add_dev - add a CPU device | |
1192 | * | |
1193 | * Adds the cpufreq interface for a CPU device. | |
1194 | * | |
1195 | * The Oracle says: try running cpufreq registration/unregistration concurrently | |
1196 | * with with cpu hotplugging and all hell will break loose. Tried to clean this | |
1197 | * mess up, but more thorough testing is needed. - Mathieu | |
1198 | */ | |
1199 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1da177e4 | 1200 | { |
fcf80582 | 1201 | unsigned int j, cpu = dev->id; |
65922465 | 1202 | int ret = -ENOMEM; |
7f0c020a | 1203 | struct cpufreq_policy *policy; |
1da177e4 | 1204 | unsigned long flags; |
96bbbe4a | 1205 | bool recover_policy = cpufreq_suspended; |
1da177e4 | 1206 | |
c32b6b8e AR |
1207 | if (cpu_is_offline(cpu)) |
1208 | return 0; | |
1209 | ||
2d06d8c4 | 1210 | pr_debug("adding CPU %u\n", cpu); |
1da177e4 | 1211 | |
6eed9404 VK |
1212 | if (!down_read_trylock(&cpufreq_rwsem)) |
1213 | return 0; | |
1214 | ||
bb29ae15 | 1215 | /* Check if this CPU already has a policy to manage it */ |
0d1857a1 | 1216 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
f963735a | 1217 | for_each_active_policy(policy) { |
7f0c020a | 1218 | if (cpumask_test_cpu(cpu, policy->related_cpus)) { |
0d1857a1 | 1219 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
7f0c020a | 1220 | ret = cpufreq_add_policy_cpu(policy, cpu, dev); |
6eed9404 VK |
1221 | up_read(&cpufreq_rwsem); |
1222 | return ret; | |
2eaa3e2d | 1223 | } |
fcf80582 | 1224 | } |
0d1857a1 | 1225 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1226 | |
72368d12 RW |
1227 | /* |
1228 | * Restore the saved policy when doing light-weight init and fall back | |
1229 | * to the full init if that fails. | |
1230 | */ | |
96bbbe4a | 1231 | policy = recover_policy ? cpufreq_policy_restore(cpu) : NULL; |
72368d12 | 1232 | if (!policy) { |
96bbbe4a | 1233 | recover_policy = false; |
8414809c | 1234 | policy = cpufreq_policy_alloc(); |
72368d12 RW |
1235 | if (!policy) |
1236 | goto nomem_out; | |
1237 | } | |
0d66b91e SB |
1238 | |
1239 | /* | |
1240 | * In the resume path, since we restore a saved policy, the assignment | |
1241 | * to policy->cpu is like an update of the existing policy, rather than | |
1242 | * the creation of a brand new one. So we need to perform this update | |
1243 | * by invoking update_policy_cpu(). | |
1244 | */ | |
1bfb425b VK |
1245 | if (recover_policy && cpu != policy->cpu) |
1246 | WARN_ON(update_policy_cpu(policy, cpu, dev)); | |
1247 | else | |
0d66b91e SB |
1248 | policy->cpu = cpu; |
1249 | ||
835481d9 | 1250 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1251 | |
1da177e4 LT |
1252 | /* call driver. From then on the cpufreq must be able |
1253 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1254 | */ | |
1c3d85dd | 1255 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1256 | if (ret) { |
2d06d8c4 | 1257 | pr_debug("initialization failed\n"); |
2eaa3e2d | 1258 | goto err_set_policy_cpu; |
1da177e4 | 1259 | } |
643ae6e8 | 1260 | |
6d4e81ed TV |
1261 | down_write(&policy->rwsem); |
1262 | ||
5a7e56a5 VK |
1263 | /* related cpus should atleast have policy->cpus */ |
1264 | cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); | |
1265 | ||
1266 | /* | |
1267 | * affected cpus must always be the one, which are online. We aren't | |
1268 | * managing offline cpus here. | |
1269 | */ | |
1270 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1271 | ||
96bbbe4a | 1272 | if (!recover_policy) { |
5a7e56a5 VK |
1273 | policy->user_policy.min = policy->min; |
1274 | policy->user_policy.max = policy->max; | |
6d4e81ed TV |
1275 | |
1276 | /* prepare interface data */ | |
1277 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, | |
1278 | &dev->kobj, "cpufreq"); | |
1279 | if (ret) { | |
1280 | pr_err("%s: failed to init policy->kobj: %d\n", | |
1281 | __func__, ret); | |
1282 | goto err_init_policy_kobj; | |
1283 | } | |
5a7e56a5 | 1284 | |
988bed09 VK |
1285 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1286 | for_each_cpu(j, policy->related_cpus) | |
1287 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1288 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1289 | } | |
652ed95d | 1290 | |
2ed99e39 | 1291 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1292 | policy->cur = cpufreq_driver->get(policy->cpu); |
1293 | if (!policy->cur) { | |
1294 | pr_err("%s: ->get() failed\n", __func__); | |
1295 | goto err_get_freq; | |
1296 | } | |
1297 | } | |
1298 | ||
d3916691 VK |
1299 | /* |
1300 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1301 | * frequency table present with cpufreq core. In such cases CPU might be | |
1302 | * unstable if it has to run on that frequency for long duration of time | |
1303 | * and so its better to set it to a frequency which is specified in | |
1304 | * freq-table. This also makes cpufreq stats inconsistent as | |
1305 | * cpufreq-stats would fail to register because current frequency of CPU | |
1306 | * isn't found in freq-table. | |
1307 | * | |
1308 | * Because we don't want this change to effect boot process badly, we go | |
1309 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1310 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1311 | * is initialized to zero). | |
1312 | * | |
1313 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1314 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1315 | * equal to target-freq. | |
1316 | */ | |
1317 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1318 | && has_target()) { | |
1319 | /* Are we running at unknown frequency ? */ | |
1320 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1321 | if (ret == -EINVAL) { | |
1322 | /* Warn user and fix it */ | |
1323 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1324 | __func__, policy->cpu, policy->cur); | |
1325 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1326 | CPUFREQ_RELATION_L); | |
1327 | ||
1328 | /* | |
1329 | * Reaching here after boot in a few seconds may not | |
1330 | * mean that system will remain stable at "unknown" | |
1331 | * frequency for longer duration. Hence, a BUG_ON(). | |
1332 | */ | |
1333 | BUG_ON(ret); | |
1334 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1335 | __func__, policy->cpu, policy->cur); | |
1336 | } | |
1337 | } | |
1338 | ||
a1531acd TR |
1339 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1340 | CPUFREQ_START, policy); | |
1341 | ||
96bbbe4a | 1342 | if (!recover_policy) { |
308b60e7 | 1343 | ret = cpufreq_add_dev_interface(policy, dev); |
a82fab29 SB |
1344 | if (ret) |
1345 | goto err_out_unregister; | |
fcd7af91 VK |
1346 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1347 | CPUFREQ_CREATE_POLICY, policy); | |
8ff69732 | 1348 | |
988bed09 VK |
1349 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1350 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1351 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1352 | } | |
9515f4d6 | 1353 | |
e18f1682 SB |
1354 | cpufreq_init_policy(policy); |
1355 | ||
96bbbe4a | 1356 | if (!recover_policy) { |
08fd8c1c VK |
1357 | policy->user_policy.policy = policy->policy; |
1358 | policy->user_policy.governor = policy->governor; | |
1359 | } | |
4e97b631 | 1360 | up_write(&policy->rwsem); |
08fd8c1c | 1361 | |
038c5b3e | 1362 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1363 | |
6eed9404 VK |
1364 | up_read(&cpufreq_rwsem); |
1365 | ||
7c45cf31 VK |
1366 | /* Callback for handling stuff after policy is ready */ |
1367 | if (cpufreq_driver->ready) | |
1368 | cpufreq_driver->ready(policy); | |
1369 | ||
2d06d8c4 | 1370 | pr_debug("initialization complete\n"); |
87c32271 | 1371 | |
1da177e4 LT |
1372 | return 0; |
1373 | ||
1da177e4 | 1374 | err_out_unregister: |
652ed95d | 1375 | err_get_freq: |
6d4e81ed TV |
1376 | if (!recover_policy) { |
1377 | kobject_put(&policy->kobj); | |
1378 | wait_for_completion(&policy->kobj_unregister); | |
1379 | } | |
1380 | err_init_policy_kobj: | |
7106e02b PB |
1381 | up_write(&policy->rwsem); |
1382 | ||
da60ce9f VK |
1383 | if (cpufreq_driver->exit) |
1384 | cpufreq_driver->exit(policy); | |
2eaa3e2d | 1385 | err_set_policy_cpu: |
96bbbe4a | 1386 | if (recover_policy) { |
72368d12 RW |
1387 | /* Do not leave stale fallback data behind. */ |
1388 | per_cpu(cpufreq_cpu_data_fallback, cpu) = NULL; | |
42f921a6 | 1389 | cpufreq_policy_put_kobj(policy); |
72368d12 | 1390 | } |
e9698cc5 | 1391 | cpufreq_policy_free(policy); |
42f921a6 | 1392 | |
1da177e4 | 1393 | nomem_out: |
6eed9404 VK |
1394 | up_read(&cpufreq_rwsem); |
1395 | ||
1da177e4 LT |
1396 | return ret; |
1397 | } | |
1398 | ||
cedb70af | 1399 | static int __cpufreq_remove_dev_prepare(struct device *dev, |
96bbbe4a | 1400 | struct subsys_interface *sif) |
1da177e4 | 1401 | { |
f9ba680d | 1402 | unsigned int cpu = dev->id, cpus; |
1bfb425b | 1403 | int ret; |
1da177e4 | 1404 | unsigned long flags; |
3a3e9e06 | 1405 | struct cpufreq_policy *policy; |
1da177e4 | 1406 | |
b8eed8af | 1407 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1408 | |
0d1857a1 | 1409 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
2eaa3e2d | 1410 | |
988bed09 | 1411 | policy = cpufreq_cpu_get_raw(cpu); |
2eaa3e2d | 1412 | |
8414809c | 1413 | /* Save the policy somewhere when doing a light-weight tear-down */ |
96bbbe4a | 1414 | if (cpufreq_suspended) |
3a3e9e06 | 1415 | per_cpu(cpufreq_cpu_data_fallback, cpu) = policy; |
8414809c | 1416 | |
0d1857a1 | 1417 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 1418 | |
3a3e9e06 | 1419 | if (!policy) { |
b8eed8af | 1420 | pr_debug("%s: No cpu_data found\n", __func__); |
1da177e4 LT |
1421 | return -EINVAL; |
1422 | } | |
1da177e4 | 1423 | |
9c0ebcf7 | 1424 | if (has_target()) { |
3de9bdeb VK |
1425 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
1426 | if (ret) { | |
1427 | pr_err("%s: Failed to stop governor\n", __func__); | |
1428 | return ret; | |
1429 | } | |
1da177e4 | 1430 | |
fa69e33f | 1431 | strncpy(per_cpu(cpufreq_cpu_governor, cpu), |
3a3e9e06 | 1432 | policy->governor->name, CPUFREQ_NAME_LEN); |
db5f2995 | 1433 | } |
1da177e4 | 1434 | |
ad7722da | 1435 | down_read(&policy->rwsem); |
3a3e9e06 | 1436 | cpus = cpumask_weight(policy->cpus); |
ad7722da | 1437 | up_read(&policy->rwsem); |
084f3493 | 1438 | |
61173f25 | 1439 | if (cpu != policy->cpu) { |
6964d91d | 1440 | sysfs_remove_link(&dev->kobj, "cpufreq"); |
73bf0fc2 | 1441 | } else if (cpus > 1) { |
1bfb425b VK |
1442 | /* Nominate new CPU */ |
1443 | int new_cpu = cpumask_any_but(policy->cpus, cpu); | |
1444 | struct device *cpu_dev = get_cpu_device(new_cpu); | |
a82fab29 | 1445 | |
1bfb425b VK |
1446 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); |
1447 | ret = update_policy_cpu(policy, new_cpu, cpu_dev); | |
1448 | if (ret) { | |
1449 | if (sysfs_create_link(&cpu_dev->kobj, &policy->kobj, | |
1450 | "cpufreq")) | |
1451 | pr_err("%s: Failed to restore kobj link to cpu:%d\n", | |
1452 | __func__, cpu_dev->id); | |
1453 | return ret; | |
1da177e4 | 1454 | } |
1bfb425b VK |
1455 | |
1456 | if (!cpufreq_suspended) | |
1457 | pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n", | |
1458 | __func__, new_cpu, cpu); | |
789ca243 | 1459 | } else if (cpufreq_driver->stop_cpu) { |
367dc4aa | 1460 | cpufreq_driver->stop_cpu(policy); |
1da177e4 | 1461 | } |
1da177e4 | 1462 | |
cedb70af SB |
1463 | return 0; |
1464 | } | |
1465 | ||
1466 | static int __cpufreq_remove_dev_finish(struct device *dev, | |
96bbbe4a | 1467 | struct subsys_interface *sif) |
cedb70af | 1468 | { |
988bed09 | 1469 | unsigned int cpu = dev->id; |
cedb70af | 1470 | int ret; |
988bed09 | 1471 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); |
cedb70af SB |
1472 | |
1473 | if (!policy) { | |
1474 | pr_debug("%s: No cpu_data found\n", __func__); | |
1475 | return -EINVAL; | |
1476 | } | |
1477 | ||
ad7722da | 1478 | down_write(&policy->rwsem); |
303ae723 | 1479 | cpumask_clear_cpu(cpu, policy->cpus); |
ad7722da | 1480 | up_write(&policy->rwsem); |
cedb70af | 1481 | |
b8eed8af | 1482 | /* If cpu is last user of policy, free policy */ |
988bed09 | 1483 | if (policy_is_inactive(policy)) { |
9c0ebcf7 | 1484 | if (has_target()) { |
3de9bdeb VK |
1485 | ret = __cpufreq_governor(policy, |
1486 | CPUFREQ_GOV_POLICY_EXIT); | |
1487 | if (ret) { | |
1488 | pr_err("%s: Failed to exit governor\n", | |
e837f9b5 | 1489 | __func__); |
3de9bdeb VK |
1490 | return ret; |
1491 | } | |
edab2fbc | 1492 | } |
2a998599 | 1493 | |
96bbbe4a | 1494 | if (!cpufreq_suspended) |
42f921a6 | 1495 | cpufreq_policy_put_kobj(policy); |
7d26e2d5 | 1496 | |
8414809c SB |
1497 | /* |
1498 | * Perform the ->exit() even during light-weight tear-down, | |
1499 | * since this is a core component, and is essential for the | |
1500 | * subsequent light-weight ->init() to succeed. | |
b8eed8af | 1501 | */ |
1c3d85dd | 1502 | if (cpufreq_driver->exit) |
3a3e9e06 | 1503 | cpufreq_driver->exit(policy); |
27ecddc2 | 1504 | |
96bbbe4a | 1505 | if (!cpufreq_suspended) |
3a3e9e06 | 1506 | cpufreq_policy_free(policy); |
e5c87b76 SK |
1507 | } else if (has_target()) { |
1508 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
1509 | if (!ret) | |
1510 | ret = __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1511 | ||
1512 | if (ret) { | |
1513 | pr_err("%s: Failed to start governor\n", __func__); | |
1514 | return ret; | |
2a998599 | 1515 | } |
27ecddc2 | 1516 | } |
1da177e4 | 1517 | |
1da177e4 LT |
1518 | return 0; |
1519 | } | |
1520 | ||
cedb70af | 1521 | /** |
27a862e9 | 1522 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1523 | * |
1524 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1525 | */ |
8a25a2fd | 1526 | static int cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1527 | { |
8a25a2fd | 1528 | unsigned int cpu = dev->id; |
27a862e9 | 1529 | int ret; |
ec28297a VP |
1530 | |
1531 | if (cpu_is_offline(cpu)) | |
1532 | return 0; | |
1533 | ||
96bbbe4a | 1534 | ret = __cpufreq_remove_dev_prepare(dev, sif); |
27a862e9 VK |
1535 | |
1536 | if (!ret) | |
96bbbe4a | 1537 | ret = __cpufreq_remove_dev_finish(dev, sif); |
27a862e9 VK |
1538 | |
1539 | return ret; | |
5a01f2e8 VP |
1540 | } |
1541 | ||
65f27f38 | 1542 | static void handle_update(struct work_struct *work) |
1da177e4 | 1543 | { |
65f27f38 DH |
1544 | struct cpufreq_policy *policy = |
1545 | container_of(work, struct cpufreq_policy, update); | |
1546 | unsigned int cpu = policy->cpu; | |
2d06d8c4 | 1547 | pr_debug("handle_update for cpu %u called\n", cpu); |
1da177e4 LT |
1548 | cpufreq_update_policy(cpu); |
1549 | } | |
1550 | ||
1551 | /** | |
bb176f7d VK |
1552 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1553 | * in deep trouble. | |
a1e1dc41 | 1554 | * @policy: policy managing CPUs |
1da177e4 LT |
1555 | * @new_freq: CPU frequency the CPU actually runs at |
1556 | * | |
29464f28 DJ |
1557 | * We adjust to current frequency first, and need to clean up later. |
1558 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1559 | */ |
a1e1dc41 | 1560 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1561 | unsigned int new_freq) |
1da177e4 LT |
1562 | { |
1563 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1564 | |
e837f9b5 | 1565 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1566 | policy->cur, new_freq); |
1da177e4 | 1567 | |
a1e1dc41 | 1568 | freqs.old = policy->cur; |
1da177e4 | 1569 | freqs.new = new_freq; |
b43a7ffb | 1570 | |
8fec051e VK |
1571 | cpufreq_freq_transition_begin(policy, &freqs); |
1572 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1573 | } |
1574 | ||
32ee8c3e | 1575 | /** |
4ab70df4 | 1576 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1577 | * @cpu: CPU number |
1578 | * | |
1579 | * This is the last known freq, without actually getting it from the driver. | |
1580 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1581 | */ | |
1582 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1583 | { | |
9e21ba8b | 1584 | struct cpufreq_policy *policy; |
e08f5f5b | 1585 | unsigned int ret_freq = 0; |
95235ca2 | 1586 | |
1c3d85dd RW |
1587 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1588 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1589 | |
1590 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1591 | if (policy) { |
e08f5f5b | 1592 | ret_freq = policy->cur; |
95235ca2 VP |
1593 | cpufreq_cpu_put(policy); |
1594 | } | |
1595 | ||
4d34a67d | 1596 | return ret_freq; |
95235ca2 VP |
1597 | } |
1598 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1599 | ||
3d737108 JB |
1600 | /** |
1601 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1602 | * @cpu: CPU number | |
1603 | * | |
1604 | * Just return the max possible frequency for a given CPU. | |
1605 | */ | |
1606 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1607 | { | |
1608 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1609 | unsigned int ret_freq = 0; | |
1610 | ||
1611 | if (policy) { | |
1612 | ret_freq = policy->max; | |
1613 | cpufreq_cpu_put(policy); | |
1614 | } | |
1615 | ||
1616 | return ret_freq; | |
1617 | } | |
1618 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1619 | ||
d92d50a4 | 1620 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1621 | { |
e08f5f5b | 1622 | unsigned int ret_freq = 0; |
5800043b | 1623 | |
1c3d85dd | 1624 | if (!cpufreq_driver->get) |
4d34a67d | 1625 | return ret_freq; |
1da177e4 | 1626 | |
d92d50a4 | 1627 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1628 | |
e08f5f5b | 1629 | if (ret_freq && policy->cur && |
1c3d85dd | 1630 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1631 | /* verify no discrepancy between actual and |
1632 | saved value exists */ | |
1633 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1634 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1635 | schedule_work(&policy->update); |
1636 | } | |
1637 | } | |
1638 | ||
4d34a67d | 1639 | return ret_freq; |
5a01f2e8 | 1640 | } |
1da177e4 | 1641 | |
5a01f2e8 VP |
1642 | /** |
1643 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1644 | * @cpu: CPU number | |
1645 | * | |
1646 | * Get the CPU current (static) CPU frequency | |
1647 | */ | |
1648 | unsigned int cpufreq_get(unsigned int cpu) | |
1649 | { | |
999976e0 | 1650 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1651 | unsigned int ret_freq = 0; |
5a01f2e8 | 1652 | |
999976e0 AP |
1653 | if (policy) { |
1654 | down_read(&policy->rwsem); | |
d92d50a4 | 1655 | ret_freq = __cpufreq_get(policy); |
999976e0 | 1656 | up_read(&policy->rwsem); |
5a01f2e8 | 1657 | |
999976e0 AP |
1658 | cpufreq_cpu_put(policy); |
1659 | } | |
6eed9404 | 1660 | |
4d34a67d | 1661 | return ret_freq; |
1da177e4 LT |
1662 | } |
1663 | EXPORT_SYMBOL(cpufreq_get); | |
1664 | ||
8a25a2fd KS |
1665 | static struct subsys_interface cpufreq_interface = { |
1666 | .name = "cpufreq", | |
1667 | .subsys = &cpu_subsys, | |
1668 | .add_dev = cpufreq_add_dev, | |
1669 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1670 | }; |
1671 | ||
e28867ea VK |
1672 | /* |
1673 | * In case platform wants some specific frequency to be configured | |
1674 | * during suspend.. | |
1675 | */ | |
1676 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1677 | { | |
1678 | int ret; | |
1679 | ||
1680 | if (!policy->suspend_freq) { | |
1681 | pr_err("%s: suspend_freq can't be zero\n", __func__); | |
1682 | return -EINVAL; | |
1683 | } | |
1684 | ||
1685 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1686 | policy->suspend_freq); | |
1687 | ||
1688 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1689 | CPUFREQ_RELATION_H); | |
1690 | if (ret) | |
1691 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1692 | __func__, policy->suspend_freq, ret); | |
1693 | ||
1694 | return ret; | |
1695 | } | |
1696 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1697 | ||
42d4dc3f | 1698 | /** |
2f0aea93 | 1699 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1700 | * |
2f0aea93 VK |
1701 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1702 | * as some platforms can't change frequency after this point in suspend cycle. | |
1703 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1704 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1705 | */ |
2f0aea93 | 1706 | void cpufreq_suspend(void) |
42d4dc3f | 1707 | { |
3a3e9e06 | 1708 | struct cpufreq_policy *policy; |
42d4dc3f | 1709 | |
2f0aea93 VK |
1710 | if (!cpufreq_driver) |
1711 | return; | |
42d4dc3f | 1712 | |
2f0aea93 | 1713 | if (!has_target()) |
b1b12bab | 1714 | goto suspend; |
42d4dc3f | 1715 | |
2f0aea93 VK |
1716 | pr_debug("%s: Suspending Governors\n", __func__); |
1717 | ||
f963735a | 1718 | for_each_active_policy(policy) { |
2f0aea93 VK |
1719 | if (__cpufreq_governor(policy, CPUFREQ_GOV_STOP)) |
1720 | pr_err("%s: Failed to stop governor for policy: %p\n", | |
1721 | __func__, policy); | |
1722 | else if (cpufreq_driver->suspend | |
1723 | && cpufreq_driver->suspend(policy)) | |
1724 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1725 | policy); | |
42d4dc3f | 1726 | } |
b1b12bab VK |
1727 | |
1728 | suspend: | |
1729 | cpufreq_suspended = true; | |
42d4dc3f BH |
1730 | } |
1731 | ||
1da177e4 | 1732 | /** |
2f0aea93 | 1733 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1734 | * |
2f0aea93 VK |
1735 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1736 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1737 | */ |
2f0aea93 | 1738 | void cpufreq_resume(void) |
1da177e4 | 1739 | { |
3a3e9e06 | 1740 | struct cpufreq_policy *policy; |
1da177e4 | 1741 | |
2f0aea93 VK |
1742 | if (!cpufreq_driver) |
1743 | return; | |
1da177e4 | 1744 | |
8e30444e LT |
1745 | cpufreq_suspended = false; |
1746 | ||
2f0aea93 | 1747 | if (!has_target()) |
e00e56df | 1748 | return; |
1da177e4 | 1749 | |
2f0aea93 | 1750 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1751 | |
f963735a | 1752 | for_each_active_policy(policy) { |
0c5aa405 VK |
1753 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) |
1754 | pr_err("%s: Failed to resume driver: %p\n", __func__, | |
1755 | policy); | |
1756 | else if (__cpufreq_governor(policy, CPUFREQ_GOV_START) | |
2f0aea93 VK |
1757 | || __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS)) |
1758 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1759 | __func__, policy); | |
2f0aea93 | 1760 | } |
c75de0ac VK |
1761 | |
1762 | /* | |
1763 | * schedule call cpufreq_update_policy() for first-online CPU, as that | |
1764 | * wouldn't be hotplugged-out on suspend. It will verify that the | |
1765 | * current freq is in sync with what we believe it to be. | |
1766 | */ | |
1767 | policy = cpufreq_cpu_get_raw(cpumask_first(cpu_online_mask)); | |
1768 | if (WARN_ON(!policy)) | |
1769 | return; | |
1770 | ||
1771 | schedule_work(&policy->update); | |
2f0aea93 | 1772 | } |
1da177e4 | 1773 | |
9d95046e BP |
1774 | /** |
1775 | * cpufreq_get_current_driver - return current driver's name | |
1776 | * | |
1777 | * Return the name string of the currently loaded cpufreq driver | |
1778 | * or NULL, if none. | |
1779 | */ | |
1780 | const char *cpufreq_get_current_driver(void) | |
1781 | { | |
1c3d85dd RW |
1782 | if (cpufreq_driver) |
1783 | return cpufreq_driver->name; | |
1784 | ||
1785 | return NULL; | |
9d95046e BP |
1786 | } |
1787 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1788 | |
51315cdf TP |
1789 | /** |
1790 | * cpufreq_get_driver_data - return current driver data | |
1791 | * | |
1792 | * Return the private data of the currently loaded cpufreq | |
1793 | * driver, or NULL if no cpufreq driver is loaded. | |
1794 | */ | |
1795 | void *cpufreq_get_driver_data(void) | |
1796 | { | |
1797 | if (cpufreq_driver) | |
1798 | return cpufreq_driver->driver_data; | |
1799 | ||
1800 | return NULL; | |
1801 | } | |
1802 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1803 | ||
1da177e4 LT |
1804 | /********************************************************************* |
1805 | * NOTIFIER LISTS INTERFACE * | |
1806 | *********************************************************************/ | |
1807 | ||
1808 | /** | |
1809 | * cpufreq_register_notifier - register a driver with cpufreq | |
1810 | * @nb: notifier function to register | |
1811 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1812 | * | |
32ee8c3e | 1813 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1814 | * are notified about clock rate changes (once before and once after |
1815 | * the transition), or a list of drivers that are notified about | |
1816 | * changes in cpufreq policy. | |
1817 | * | |
1818 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1819 | * blocking_notifier_chain_register. |
1da177e4 LT |
1820 | */ |
1821 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1822 | { | |
1823 | int ret; | |
1824 | ||
d5aaffa9 DB |
1825 | if (cpufreq_disabled()) |
1826 | return -EINVAL; | |
1827 | ||
74212ca4 CEB |
1828 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1829 | ||
1da177e4 LT |
1830 | switch (list) { |
1831 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1832 | ret = srcu_notifier_chain_register( |
e041c683 | 1833 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1834 | break; |
1835 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1836 | ret = blocking_notifier_chain_register( |
1837 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1838 | break; |
1839 | default: | |
1840 | ret = -EINVAL; | |
1841 | } | |
1da177e4 LT |
1842 | |
1843 | return ret; | |
1844 | } | |
1845 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1846 | ||
1da177e4 LT |
1847 | /** |
1848 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1849 | * @nb: notifier block to be unregistered | |
bb176f7d | 1850 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1851 | * |
1852 | * Remove a driver from the CPU frequency notifier list. | |
1853 | * | |
1854 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1855 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1856 | */ |
1857 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1858 | { | |
1859 | int ret; | |
1860 | ||
d5aaffa9 DB |
1861 | if (cpufreq_disabled()) |
1862 | return -EINVAL; | |
1863 | ||
1da177e4 LT |
1864 | switch (list) { |
1865 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1866 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1867 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1868 | break; |
1869 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1870 | ret = blocking_notifier_chain_unregister( |
1871 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1872 | break; |
1873 | default: | |
1874 | ret = -EINVAL; | |
1875 | } | |
1da177e4 LT |
1876 | |
1877 | return ret; | |
1878 | } | |
1879 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1880 | ||
1881 | ||
1882 | /********************************************************************* | |
1883 | * GOVERNORS * | |
1884 | *********************************************************************/ | |
1885 | ||
1c03a2d0 VK |
1886 | /* Must set freqs->new to intermediate frequency */ |
1887 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1888 | struct cpufreq_freqs *freqs, int index) | |
1889 | { | |
1890 | int ret; | |
1891 | ||
1892 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1893 | ||
1894 | /* We don't need to switch to intermediate freq */ | |
1895 | if (!freqs->new) | |
1896 | return 0; | |
1897 | ||
1898 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1899 | __func__, policy->cpu, freqs->old, freqs->new); | |
1900 | ||
1901 | cpufreq_freq_transition_begin(policy, freqs); | |
1902 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1903 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1904 | ||
1905 | if (ret) | |
1906 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1907 | __func__, ret); | |
1908 | ||
1909 | return ret; | |
1910 | } | |
1911 | ||
8d65775d VK |
1912 | static int __target_index(struct cpufreq_policy *policy, |
1913 | struct cpufreq_frequency_table *freq_table, int index) | |
1914 | { | |
1c03a2d0 VK |
1915 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1916 | unsigned int intermediate_freq = 0; | |
8d65775d VK |
1917 | int retval = -EINVAL; |
1918 | bool notify; | |
1919 | ||
1920 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
8d65775d | 1921 | if (notify) { |
1c03a2d0 VK |
1922 | /* Handle switching to intermediate frequency */ |
1923 | if (cpufreq_driver->get_intermediate) { | |
1924 | retval = __target_intermediate(policy, &freqs, index); | |
1925 | if (retval) | |
1926 | return retval; | |
1927 | ||
1928 | intermediate_freq = freqs.new; | |
1929 | /* Set old freq to intermediate */ | |
1930 | if (intermediate_freq) | |
1931 | freqs.old = freqs.new; | |
1932 | } | |
8d65775d | 1933 | |
1c03a2d0 | 1934 | freqs.new = freq_table[index].frequency; |
8d65775d VK |
1935 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1936 | __func__, policy->cpu, freqs.old, freqs.new); | |
1937 | ||
1938 | cpufreq_freq_transition_begin(policy, &freqs); | |
1939 | } | |
1940 | ||
1941 | retval = cpufreq_driver->target_index(policy, index); | |
1942 | if (retval) | |
1943 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1944 | retval); | |
1945 | ||
1c03a2d0 | 1946 | if (notify) { |
8d65775d VK |
1947 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1948 | ||
1c03a2d0 VK |
1949 | /* |
1950 | * Failed after setting to intermediate freq? Driver should have | |
1951 | * reverted back to initial frequency and so should we. Check | |
1952 | * here for intermediate_freq instead of get_intermediate, in | |
1953 | * case we have't switched to intermediate freq at all. | |
1954 | */ | |
1955 | if (unlikely(retval && intermediate_freq)) { | |
1956 | freqs.old = intermediate_freq; | |
1957 | freqs.new = policy->restore_freq; | |
1958 | cpufreq_freq_transition_begin(policy, &freqs); | |
1959 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1960 | } | |
1961 | } | |
1962 | ||
8d65775d VK |
1963 | return retval; |
1964 | } | |
1965 | ||
1da177e4 LT |
1966 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1967 | unsigned int target_freq, | |
1968 | unsigned int relation) | |
1969 | { | |
7249924e | 1970 | unsigned int old_target_freq = target_freq; |
8d65775d | 1971 | int retval = -EINVAL; |
c32b6b8e | 1972 | |
a7b422cd KRW |
1973 | if (cpufreq_disabled()) |
1974 | return -ENODEV; | |
1975 | ||
7249924e VK |
1976 | /* Make sure that target_freq is within supported range */ |
1977 | if (target_freq > policy->max) | |
1978 | target_freq = policy->max; | |
1979 | if (target_freq < policy->min) | |
1980 | target_freq = policy->min; | |
1981 | ||
1982 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1983 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1984 | |
9c0ebcf7 VK |
1985 | /* |
1986 | * This might look like a redundant call as we are checking it again | |
1987 | * after finding index. But it is left intentionally for cases where | |
1988 | * exactly same freq is called again and so we can save on few function | |
1989 | * calls. | |
1990 | */ | |
5a1c0228 VK |
1991 | if (target_freq == policy->cur) |
1992 | return 0; | |
1993 | ||
1c03a2d0 VK |
1994 | /* Save last value to restore later on errors */ |
1995 | policy->restore_freq = policy->cur; | |
1996 | ||
1c3d85dd RW |
1997 | if (cpufreq_driver->target) |
1998 | retval = cpufreq_driver->target(policy, target_freq, relation); | |
9c0ebcf7 VK |
1999 | else if (cpufreq_driver->target_index) { |
2000 | struct cpufreq_frequency_table *freq_table; | |
2001 | int index; | |
90d45d17 | 2002 | |
9c0ebcf7 VK |
2003 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2004 | if (unlikely(!freq_table)) { | |
2005 | pr_err("%s: Unable to find freq_table\n", __func__); | |
2006 | goto out; | |
2007 | } | |
2008 | ||
2009 | retval = cpufreq_frequency_table_target(policy, freq_table, | |
2010 | target_freq, relation, &index); | |
2011 | if (unlikely(retval)) { | |
2012 | pr_err("%s: Unable to find matching freq\n", __func__); | |
2013 | goto out; | |
2014 | } | |
2015 | ||
d4019f0a | 2016 | if (freq_table[index].frequency == policy->cur) { |
9c0ebcf7 | 2017 | retval = 0; |
d4019f0a VK |
2018 | goto out; |
2019 | } | |
2020 | ||
8d65775d | 2021 | retval = __target_index(policy, freq_table, index); |
9c0ebcf7 VK |
2022 | } |
2023 | ||
2024 | out: | |
1da177e4 LT |
2025 | return retval; |
2026 | } | |
2027 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
2028 | ||
1da177e4 LT |
2029 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
2030 | unsigned int target_freq, | |
2031 | unsigned int relation) | |
2032 | { | |
f1829e4a | 2033 | int ret = -EINVAL; |
1da177e4 | 2034 | |
ad7722da | 2035 | down_write(&policy->rwsem); |
1da177e4 LT |
2036 | |
2037 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
2038 | ||
ad7722da | 2039 | up_write(&policy->rwsem); |
1da177e4 | 2040 | |
1da177e4 LT |
2041 | return ret; |
2042 | } | |
2043 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
2044 | ||
e08f5f5b GS |
2045 | static int __cpufreq_governor(struct cpufreq_policy *policy, |
2046 | unsigned int event) | |
1da177e4 | 2047 | { |
cc993cab | 2048 | int ret; |
6afde10c TR |
2049 | |
2050 | /* Only must be defined when default governor is known to have latency | |
2051 | restrictions, like e.g. conservative or ondemand. | |
2052 | That this is the case is already ensured in Kconfig | |
2053 | */ | |
2054 | #ifdef CONFIG_CPU_FREQ_GOV_PERFORMANCE | |
2055 | struct cpufreq_governor *gov = &cpufreq_gov_performance; | |
2056 | #else | |
2057 | struct cpufreq_governor *gov = NULL; | |
2058 | #endif | |
1c256245 | 2059 | |
2f0aea93 VK |
2060 | /* Don't start any governor operations if we are entering suspend */ |
2061 | if (cpufreq_suspended) | |
2062 | return 0; | |
cb57720b EZ |
2063 | /* |
2064 | * Governor might not be initiated here if ACPI _PPC changed | |
2065 | * notification happened, so check it. | |
2066 | */ | |
2067 | if (!policy->governor) | |
2068 | return -EINVAL; | |
2f0aea93 | 2069 | |
1c256245 TR |
2070 | if (policy->governor->max_transition_latency && |
2071 | policy->cpuinfo.transition_latency > | |
2072 | policy->governor->max_transition_latency) { | |
6afde10c TR |
2073 | if (!gov) |
2074 | return -EINVAL; | |
2075 | else { | |
e837f9b5 JP |
2076 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
2077 | policy->governor->name, gov->name); | |
6afde10c TR |
2078 | policy->governor = gov; |
2079 | } | |
1c256245 | 2080 | } |
1da177e4 | 2081 | |
fe492f3f VK |
2082 | if (event == CPUFREQ_GOV_POLICY_INIT) |
2083 | if (!try_module_get(policy->governor->owner)) | |
2084 | return -EINVAL; | |
1da177e4 | 2085 | |
2d06d8c4 | 2086 | pr_debug("__cpufreq_governor for CPU %u, event %u\n", |
e837f9b5 | 2087 | policy->cpu, event); |
95731ebb XC |
2088 | |
2089 | mutex_lock(&cpufreq_governor_lock); | |
56d07db2 | 2090 | if ((policy->governor_enabled && event == CPUFREQ_GOV_START) |
f73d3933 VK |
2091 | || (!policy->governor_enabled |
2092 | && (event == CPUFREQ_GOV_LIMITS || event == CPUFREQ_GOV_STOP))) { | |
95731ebb XC |
2093 | mutex_unlock(&cpufreq_governor_lock); |
2094 | return -EBUSY; | |
2095 | } | |
2096 | ||
2097 | if (event == CPUFREQ_GOV_STOP) | |
2098 | policy->governor_enabled = false; | |
2099 | else if (event == CPUFREQ_GOV_START) | |
2100 | policy->governor_enabled = true; | |
2101 | ||
2102 | mutex_unlock(&cpufreq_governor_lock); | |
2103 | ||
1da177e4 LT |
2104 | ret = policy->governor->governor(policy, event); |
2105 | ||
4d5dcc42 VK |
2106 | if (!ret) { |
2107 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
2108 | policy->governor->initialized++; | |
2109 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
2110 | policy->governor->initialized--; | |
95731ebb XC |
2111 | } else { |
2112 | /* Restore original values */ | |
2113 | mutex_lock(&cpufreq_governor_lock); | |
2114 | if (event == CPUFREQ_GOV_STOP) | |
2115 | policy->governor_enabled = true; | |
2116 | else if (event == CPUFREQ_GOV_START) | |
2117 | policy->governor_enabled = false; | |
2118 | mutex_unlock(&cpufreq_governor_lock); | |
4d5dcc42 | 2119 | } |
b394058f | 2120 | |
fe492f3f VK |
2121 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
2122 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
2123 | module_put(policy->governor->owner); |
2124 | ||
2125 | return ret; | |
2126 | } | |
2127 | ||
1da177e4 LT |
2128 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
2129 | { | |
3bcb09a3 | 2130 | int err; |
1da177e4 LT |
2131 | |
2132 | if (!governor) | |
2133 | return -EINVAL; | |
2134 | ||
a7b422cd KRW |
2135 | if (cpufreq_disabled()) |
2136 | return -ENODEV; | |
2137 | ||
3fc54d37 | 2138 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 2139 | |
b394058f | 2140 | governor->initialized = 0; |
3bcb09a3 | 2141 | err = -EBUSY; |
42f91fa1 | 2142 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
2143 | err = 0; |
2144 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 2145 | } |
1da177e4 | 2146 | |
32ee8c3e | 2147 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 2148 | return err; |
1da177e4 LT |
2149 | } |
2150 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
2151 | ||
1da177e4 LT |
2152 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
2153 | { | |
90e41bac | 2154 | int cpu; |
90e41bac | 2155 | |
1da177e4 LT |
2156 | if (!governor) |
2157 | return; | |
2158 | ||
a7b422cd KRW |
2159 | if (cpufreq_disabled()) |
2160 | return; | |
2161 | ||
90e41bac PB |
2162 | for_each_present_cpu(cpu) { |
2163 | if (cpu_online(cpu)) | |
2164 | continue; | |
2165 | if (!strcmp(per_cpu(cpufreq_cpu_governor, cpu), governor->name)) | |
2166 | strcpy(per_cpu(cpufreq_cpu_governor, cpu), "\0"); | |
2167 | } | |
90e41bac | 2168 | |
3fc54d37 | 2169 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 2170 | list_del(&governor->governor_list); |
3fc54d37 | 2171 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
2172 | return; |
2173 | } | |
2174 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
2175 | ||
2176 | ||
1da177e4 LT |
2177 | /********************************************************************* |
2178 | * POLICY INTERFACE * | |
2179 | *********************************************************************/ | |
2180 | ||
2181 | /** | |
2182 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
2183 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
2184 | * is written | |
1da177e4 LT |
2185 | * |
2186 | * Reads the current cpufreq policy. | |
2187 | */ | |
2188 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
2189 | { | |
2190 | struct cpufreq_policy *cpu_policy; | |
2191 | if (!policy) | |
2192 | return -EINVAL; | |
2193 | ||
2194 | cpu_policy = cpufreq_cpu_get(cpu); | |
2195 | if (!cpu_policy) | |
2196 | return -EINVAL; | |
2197 | ||
d5b73cd8 | 2198 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2199 | |
2200 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2201 | return 0; |
2202 | } | |
2203 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2204 | ||
153d7f3f | 2205 | /* |
037ce839 VK |
2206 | * policy : current policy. |
2207 | * new_policy: policy to be set. | |
153d7f3f | 2208 | */ |
037ce839 | 2209 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2210 | struct cpufreq_policy *new_policy) |
1da177e4 | 2211 | { |
d9a789c7 RW |
2212 | struct cpufreq_governor *old_gov; |
2213 | int ret; | |
1da177e4 | 2214 | |
e837f9b5 JP |
2215 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2216 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2217 | |
d5b73cd8 | 2218 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2219 | |
d9a789c7 RW |
2220 | if (new_policy->min > policy->max || new_policy->max < policy->min) |
2221 | return -EINVAL; | |
9c9a43ed | 2222 | |
1da177e4 | 2223 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2224 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2225 | if (ret) |
d9a789c7 | 2226 | return ret; |
1da177e4 | 2227 | |
1da177e4 | 2228 | /* adjust if necessary - all reasons */ |
e041c683 | 2229 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2230 | CPUFREQ_ADJUST, new_policy); |
1da177e4 LT |
2231 | |
2232 | /* adjust if necessary - hardware incompatibility*/ | |
e041c683 | 2233 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2234 | CPUFREQ_INCOMPATIBLE, new_policy); |
1da177e4 | 2235 | |
bb176f7d VK |
2236 | /* |
2237 | * verify the cpu speed can be set within this limit, which might be | |
2238 | * different to the first one | |
2239 | */ | |
3a3e9e06 | 2240 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2241 | if (ret) |
d9a789c7 | 2242 | return ret; |
1da177e4 LT |
2243 | |
2244 | /* notification of the new policy */ | |
e041c683 | 2245 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2246 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2247 | |
3a3e9e06 VK |
2248 | policy->min = new_policy->min; |
2249 | policy->max = new_policy->max; | |
1da177e4 | 2250 | |
2d06d8c4 | 2251 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2252 | policy->min, policy->max); |
1da177e4 | 2253 | |
1c3d85dd | 2254 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2255 | policy->policy = new_policy->policy; |
2d06d8c4 | 2256 | pr_debug("setting range\n"); |
d9a789c7 RW |
2257 | return cpufreq_driver->setpolicy(new_policy); |
2258 | } | |
1da177e4 | 2259 | |
d9a789c7 RW |
2260 | if (new_policy->governor == policy->governor) |
2261 | goto out; | |
7bd353a9 | 2262 | |
d9a789c7 RW |
2263 | pr_debug("governor switch\n"); |
2264 | ||
2265 | /* save old, working values */ | |
2266 | old_gov = policy->governor; | |
2267 | /* end old governor */ | |
2268 | if (old_gov) { | |
2269 | __cpufreq_governor(policy, CPUFREQ_GOV_STOP); | |
2270 | up_write(&policy->rwsem); | |
e5c87b76 | 2271 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
d9a789c7 | 2272 | down_write(&policy->rwsem); |
1da177e4 LT |
2273 | } |
2274 | ||
d9a789c7 RW |
2275 | /* start new governor */ |
2276 | policy->governor = new_policy->governor; | |
2277 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) { | |
2278 | if (!__cpufreq_governor(policy, CPUFREQ_GOV_START)) | |
2279 | goto out; | |
2280 | ||
2281 | up_write(&policy->rwsem); | |
2282 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); | |
2283 | down_write(&policy->rwsem); | |
2284 | } | |
2285 | ||
2286 | /* new governor failed, so re-start old one */ | |
2287 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2288 | if (old_gov) { | |
2289 | policy->governor = old_gov; | |
2290 | __cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); | |
2291 | __cpufreq_governor(policy, CPUFREQ_GOV_START); | |
2292 | } | |
2293 | ||
2294 | return -EINVAL; | |
2295 | ||
2296 | out: | |
2297 | pr_debug("governor: change or update limits\n"); | |
2298 | return __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
1da177e4 LT |
2299 | } |
2300 | ||
1da177e4 LT |
2301 | /** |
2302 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2303 | * @cpu: CPU which shall be re-evaluated | |
2304 | * | |
25985edc | 2305 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2306 | * at different times. |
2307 | */ | |
2308 | int cpufreq_update_policy(unsigned int cpu) | |
2309 | { | |
3a3e9e06 VK |
2310 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2311 | struct cpufreq_policy new_policy; | |
f1829e4a | 2312 | int ret; |
1da177e4 | 2313 | |
fefa8ff8 AP |
2314 | if (!policy) |
2315 | return -ENODEV; | |
1da177e4 | 2316 | |
ad7722da | 2317 | down_write(&policy->rwsem); |
1da177e4 | 2318 | |
2d06d8c4 | 2319 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2320 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2321 | new_policy.min = policy->user_policy.min; |
2322 | new_policy.max = policy->user_policy.max; | |
2323 | new_policy.policy = policy->user_policy.policy; | |
2324 | new_policy.governor = policy->user_policy.governor; | |
1da177e4 | 2325 | |
bb176f7d VK |
2326 | /* |
2327 | * BIOS might change freq behind our back | |
2328 | * -> ask driver for current freq and notify governors about a change | |
2329 | */ | |
2ed99e39 | 2330 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
3a3e9e06 | 2331 | new_policy.cur = cpufreq_driver->get(cpu); |
bd0fa9bb VK |
2332 | if (WARN_ON(!new_policy.cur)) { |
2333 | ret = -EIO; | |
fefa8ff8 | 2334 | goto unlock; |
bd0fa9bb VK |
2335 | } |
2336 | ||
3a3e9e06 | 2337 | if (!policy->cur) { |
e837f9b5 | 2338 | pr_debug("Driver did not initialize current freq\n"); |
3a3e9e06 | 2339 | policy->cur = new_policy.cur; |
a85f7bd3 | 2340 | } else { |
9c0ebcf7 | 2341 | if (policy->cur != new_policy.cur && has_target()) |
a1e1dc41 | 2342 | cpufreq_out_of_sync(policy, new_policy.cur); |
a85f7bd3 | 2343 | } |
0961dd0d TR |
2344 | } |
2345 | ||
037ce839 | 2346 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2347 | |
fefa8ff8 | 2348 | unlock: |
ad7722da | 2349 | up_write(&policy->rwsem); |
5a01f2e8 | 2350 | |
3a3e9e06 | 2351 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2352 | return ret; |
2353 | } | |
2354 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2355 | ||
2760984f | 2356 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2357 | unsigned long action, void *hcpu) |
2358 | { | |
2359 | unsigned int cpu = (unsigned long)hcpu; | |
8a25a2fd | 2360 | struct device *dev; |
c32b6b8e | 2361 | |
8a25a2fd KS |
2362 | dev = get_cpu_device(cpu); |
2363 | if (dev) { | |
5302c3fb | 2364 | switch (action & ~CPU_TASKS_FROZEN) { |
c32b6b8e | 2365 | case CPU_ONLINE: |
23faf0b7 | 2366 | cpufreq_add_dev(dev, NULL); |
c32b6b8e | 2367 | break; |
5302c3fb | 2368 | |
c32b6b8e | 2369 | case CPU_DOWN_PREPARE: |
96bbbe4a | 2370 | __cpufreq_remove_dev_prepare(dev, NULL); |
1aee40ac SB |
2371 | break; |
2372 | ||
2373 | case CPU_POST_DEAD: | |
96bbbe4a | 2374 | __cpufreq_remove_dev_finish(dev, NULL); |
c32b6b8e | 2375 | break; |
5302c3fb | 2376 | |
5a01f2e8 | 2377 | case CPU_DOWN_FAILED: |
23faf0b7 | 2378 | cpufreq_add_dev(dev, NULL); |
c32b6b8e AR |
2379 | break; |
2380 | } | |
2381 | } | |
2382 | return NOTIFY_OK; | |
2383 | } | |
2384 | ||
9c36f746 | 2385 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2386 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2387 | }; |
1da177e4 | 2388 | |
6f19efc0 LM |
2389 | /********************************************************************* |
2390 | * BOOST * | |
2391 | *********************************************************************/ | |
2392 | static int cpufreq_boost_set_sw(int state) | |
2393 | { | |
2394 | struct cpufreq_frequency_table *freq_table; | |
2395 | struct cpufreq_policy *policy; | |
2396 | int ret = -EINVAL; | |
2397 | ||
f963735a | 2398 | for_each_active_policy(policy) { |
6f19efc0 LM |
2399 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2400 | if (freq_table) { | |
2401 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2402 | freq_table); | |
2403 | if (ret) { | |
2404 | pr_err("%s: Policy frequency update failed\n", | |
2405 | __func__); | |
2406 | break; | |
2407 | } | |
2408 | policy->user_policy.max = policy->max; | |
2409 | __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); | |
2410 | } | |
2411 | } | |
2412 | ||
2413 | return ret; | |
2414 | } | |
2415 | ||
2416 | int cpufreq_boost_trigger_state(int state) | |
2417 | { | |
2418 | unsigned long flags; | |
2419 | int ret = 0; | |
2420 | ||
2421 | if (cpufreq_driver->boost_enabled == state) | |
2422 | return 0; | |
2423 | ||
2424 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2425 | cpufreq_driver->boost_enabled = state; | |
2426 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2427 | ||
2428 | ret = cpufreq_driver->set_boost(state); | |
2429 | if (ret) { | |
2430 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2431 | cpufreq_driver->boost_enabled = !state; | |
2432 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2433 | ||
e837f9b5 JP |
2434 | pr_err("%s: Cannot %s BOOST\n", |
2435 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2436 | } |
2437 | ||
2438 | return ret; | |
2439 | } | |
2440 | ||
2441 | int cpufreq_boost_supported(void) | |
2442 | { | |
2443 | if (likely(cpufreq_driver)) | |
2444 | return cpufreq_driver->boost_supported; | |
2445 | ||
2446 | return 0; | |
2447 | } | |
2448 | EXPORT_SYMBOL_GPL(cpufreq_boost_supported); | |
2449 | ||
2450 | int cpufreq_boost_enabled(void) | |
2451 | { | |
2452 | return cpufreq_driver->boost_enabled; | |
2453 | } | |
2454 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2455 | ||
1da177e4 LT |
2456 | /********************************************************************* |
2457 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2458 | *********************************************************************/ | |
2459 | ||
2460 | /** | |
2461 | * cpufreq_register_driver - register a CPU Frequency driver | |
2462 | * @driver_data: A struct cpufreq_driver containing the values# | |
2463 | * submitted by the CPU Frequency driver. | |
2464 | * | |
bb176f7d | 2465 | * Registers a CPU Frequency driver to this core code. This code |
1da177e4 | 2466 | * returns zero on success, -EBUSY when another driver got here first |
32ee8c3e | 2467 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2468 | * |
2469 | */ | |
221dee28 | 2470 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2471 | { |
2472 | unsigned long flags; | |
2473 | int ret; | |
2474 | ||
a7b422cd KRW |
2475 | if (cpufreq_disabled()) |
2476 | return -ENODEV; | |
2477 | ||
1da177e4 | 2478 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2479 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2480 | driver_data->target) || |
2481 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2482 | driver_data->target)) || |
2483 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2484 | return -EINVAL; |
2485 | ||
2d06d8c4 | 2486 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2487 | |
0d1857a1 | 2488 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2489 | if (cpufreq_driver) { |
0d1857a1 | 2490 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4dea5806 | 2491 | return -EEXIST; |
1da177e4 | 2492 | } |
1c3d85dd | 2493 | cpufreq_driver = driver_data; |
0d1857a1 | 2494 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2495 | |
bc68b7df VK |
2496 | if (driver_data->setpolicy) |
2497 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2498 | ||
6f19efc0 LM |
2499 | if (cpufreq_boost_supported()) { |
2500 | /* | |
2501 | * Check if driver provides function to enable boost - | |
2502 | * if not, use cpufreq_boost_set_sw as default | |
2503 | */ | |
2504 | if (!cpufreq_driver->set_boost) | |
2505 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; | |
2506 | ||
2507 | ret = cpufreq_sysfs_create_file(&boost.attr); | |
2508 | if (ret) { | |
2509 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
e837f9b5 | 2510 | __func__); |
6f19efc0 LM |
2511 | goto err_null_driver; |
2512 | } | |
2513 | } | |
2514 | ||
8a25a2fd | 2515 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2516 | if (ret) |
6f19efc0 | 2517 | goto err_boost_unreg; |
1da177e4 | 2518 | |
ce1bcfe9 VK |
2519 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2520 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2521 | /* if all ->init() calls failed, unregister */ |
ce1bcfe9 VK |
2522 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2523 | driver_data->name); | |
2524 | goto err_if_unreg; | |
1da177e4 LT |
2525 | } |
2526 | ||
8f5bc2ab | 2527 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2528 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2529 | |
8f5bc2ab | 2530 | return 0; |
8a25a2fd KS |
2531 | err_if_unreg: |
2532 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 LM |
2533 | err_boost_unreg: |
2534 | if (cpufreq_boost_supported()) | |
2535 | cpufreq_sysfs_remove_file(&boost.attr); | |
8f5bc2ab | 2536 | err_null_driver: |
0d1857a1 | 2537 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2538 | cpufreq_driver = NULL; |
0d1857a1 | 2539 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
4d34a67d | 2540 | return ret; |
1da177e4 LT |
2541 | } |
2542 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2543 | ||
1da177e4 LT |
2544 | /** |
2545 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2546 | * | |
bb176f7d | 2547 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2548 | * the right to do so, i.e. if you have succeeded in initialising before! |
2549 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2550 | * currently not initialised. | |
2551 | */ | |
221dee28 | 2552 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2553 | { |
2554 | unsigned long flags; | |
2555 | ||
1c3d85dd | 2556 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2557 | return -EINVAL; |
1da177e4 | 2558 | |
2d06d8c4 | 2559 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2560 | |
8a25a2fd | 2561 | subsys_interface_unregister(&cpufreq_interface); |
6f19efc0 LM |
2562 | if (cpufreq_boost_supported()) |
2563 | cpufreq_sysfs_remove_file(&boost.attr); | |
2564 | ||
65edc68c | 2565 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2566 | |
6eed9404 | 2567 | down_write(&cpufreq_rwsem); |
0d1857a1 | 2568 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2569 | |
1c3d85dd | 2570 | cpufreq_driver = NULL; |
6eed9404 | 2571 | |
0d1857a1 | 2572 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
6eed9404 | 2573 | up_write(&cpufreq_rwsem); |
1da177e4 LT |
2574 | |
2575 | return 0; | |
2576 | } | |
2577 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2578 | |
90de2a4a DA |
2579 | /* |
2580 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2581 | * or mutexes when secondary CPUs are halted. | |
2582 | */ | |
2583 | static struct syscore_ops cpufreq_syscore_ops = { | |
2584 | .shutdown = cpufreq_suspend, | |
2585 | }; | |
2586 | ||
5a01f2e8 VP |
2587 | static int __init cpufreq_core_init(void) |
2588 | { | |
a7b422cd KRW |
2589 | if (cpufreq_disabled()) |
2590 | return -ENODEV; | |
2591 | ||
2361be23 | 2592 | cpufreq_global_kobject = kobject_create(); |
8aa84ad8 TR |
2593 | BUG_ON(!cpufreq_global_kobject); |
2594 | ||
90de2a4a DA |
2595 | register_syscore_ops(&cpufreq_syscore_ops); |
2596 | ||
5a01f2e8 VP |
2597 | return 0; |
2598 | } | |
5a01f2e8 | 2599 | core_initcall(cpufreq_core_init); |