Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/drivers/cpufreq/cpufreq.c | |
3 | * | |
4 | * Copyright (C) 2001 Russell King | |
5 | * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> | |
bb176f7d | 6 | * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> |
1da177e4 | 7 | * |
c32b6b8e | 8 | * Oct 2005 - Ashok Raj <ashok.raj@intel.com> |
32ee8c3e | 9 | * Added handling for CPU hotplug |
8ff69732 DJ |
10 | * Feb 2006 - Jacob Shin <jacob.shin@amd.com> |
11 | * Fix handling for CPU hotplug -- affected CPUs | |
c32b6b8e | 12 | * |
1da177e4 LT |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License version 2 as | |
15 | * published by the Free Software Foundation. | |
1da177e4 LT |
16 | */ |
17 | ||
db701151 VK |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
5ff0a268 | 20 | #include <linux/cpu.h> |
1da177e4 LT |
21 | #include <linux/cpufreq.h> |
22 | #include <linux/delay.h> | |
1da177e4 | 23 | #include <linux/device.h> |
5ff0a268 VK |
24 | #include <linux/init.h> |
25 | #include <linux/kernel_stat.h> | |
26 | #include <linux/module.h> | |
3fc54d37 | 27 | #include <linux/mutex.h> |
5ff0a268 | 28 | #include <linux/slab.h> |
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 | ||
f963735a | 41 | /* Macros to iterate over CPU policies */ |
fd7dc7e6 EB |
42 | #define for_each_suitable_policy(__policy, __active) \ |
43 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ | |
44 | if ((__active) == !policy_is_inactive(__policy)) | |
f963735a VK |
45 | |
46 | #define for_each_active_policy(__policy) \ | |
47 | for_each_suitable_policy(__policy, true) | |
48 | #define for_each_inactive_policy(__policy) \ | |
49 | for_each_suitable_policy(__policy, false) | |
50 | ||
51 | #define for_each_policy(__policy) \ | |
b4f0676f VK |
52 | list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) |
53 | ||
f7b27061 VK |
54 | /* Iterate over governors */ |
55 | static LIST_HEAD(cpufreq_governor_list); | |
56 | #define for_each_governor(__governor) \ | |
57 | list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) | |
58 | ||
1da177e4 | 59 | /** |
cd878479 | 60 | * The "cpufreq driver" - the arch- or hardware-dependent low |
1da177e4 LT |
61 | * level driver of CPUFreq support, and its spinlock. This lock |
62 | * also protects the cpufreq_cpu_data array. | |
63 | */ | |
1c3d85dd | 64 | static struct cpufreq_driver *cpufreq_driver; |
7a6aedfa | 65 | static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); |
bb176f7d | 66 | static DEFINE_RWLOCK(cpufreq_driver_lock); |
bb176f7d | 67 | |
2f0aea93 VK |
68 | /* Flag to suspend/resume CPUFreq governors */ |
69 | static bool cpufreq_suspended; | |
1da177e4 | 70 | |
9c0ebcf7 VK |
71 | static inline bool has_target(void) |
72 | { | |
73 | return cpufreq_driver->target_index || cpufreq_driver->target; | |
74 | } | |
75 | ||
1da177e4 | 76 | /* internal prototypes */ |
a1317e09 | 77 | static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event); |
d92d50a4 | 78 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy); |
1da177e4 LT |
79 | |
80 | /** | |
32ee8c3e DJ |
81 | * Two notifier lists: the "policy" list is involved in the |
82 | * validation process for a new CPU frequency policy; the | |
1da177e4 LT |
83 | * "transition" list for kernel code that needs to handle |
84 | * changes to devices when the CPU clock speed changes. | |
85 | * The mutex locks both lists. | |
86 | */ | |
e041c683 | 87 | static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); |
b4dfdbb3 | 88 | static struct srcu_notifier_head cpufreq_transition_notifier_list; |
1da177e4 | 89 | |
74212ca4 | 90 | static bool init_cpufreq_transition_notifier_list_called; |
b4dfdbb3 AS |
91 | static int __init init_cpufreq_transition_notifier_list(void) |
92 | { | |
93 | srcu_init_notifier_head(&cpufreq_transition_notifier_list); | |
74212ca4 | 94 | init_cpufreq_transition_notifier_list_called = true; |
b4dfdbb3 AS |
95 | return 0; |
96 | } | |
b3438f82 | 97 | pure_initcall(init_cpufreq_transition_notifier_list); |
1da177e4 | 98 | |
a7b422cd | 99 | static int off __read_mostly; |
da584455 | 100 | static int cpufreq_disabled(void) |
a7b422cd KRW |
101 | { |
102 | return off; | |
103 | } | |
104 | void disable_cpufreq(void) | |
105 | { | |
106 | off = 1; | |
107 | } | |
29464f28 | 108 | static DEFINE_MUTEX(cpufreq_governor_mutex); |
1da177e4 | 109 | |
4d5dcc42 VK |
110 | bool have_governor_per_policy(void) |
111 | { | |
0b981e70 | 112 | return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); |
4d5dcc42 | 113 | } |
3f869d6d | 114 | EXPORT_SYMBOL_GPL(have_governor_per_policy); |
4d5dcc42 | 115 | |
944e9a03 VK |
116 | struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) |
117 | { | |
118 | if (have_governor_per_policy()) | |
119 | return &policy->kobj; | |
120 | else | |
121 | return cpufreq_global_kobject; | |
122 | } | |
123 | EXPORT_SYMBOL_GPL(get_governor_parent_kobj); | |
124 | ||
5a31d594 VK |
125 | struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu) |
126 | { | |
127 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
128 | ||
129 | return policy && !policy_is_inactive(policy) ? | |
130 | policy->freq_table : NULL; | |
131 | } | |
132 | EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table); | |
133 | ||
72a4ce34 VK |
134 | static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) |
135 | { | |
136 | u64 idle_time; | |
137 | u64 cur_wall_time; | |
138 | u64 busy_time; | |
139 | ||
140 | cur_wall_time = jiffies64_to_cputime64(get_jiffies_64()); | |
141 | ||
142 | busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; | |
143 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; | |
144 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; | |
145 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; | |
146 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; | |
147 | busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; | |
148 | ||
149 | idle_time = cur_wall_time - busy_time; | |
150 | if (wall) | |
151 | *wall = cputime_to_usecs(cur_wall_time); | |
152 | ||
153 | return cputime_to_usecs(idle_time); | |
154 | } | |
155 | ||
156 | u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) | |
157 | { | |
158 | u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); | |
159 | ||
160 | if (idle_time == -1ULL) | |
161 | return get_cpu_idle_time_jiffy(cpu, wall); | |
162 | else if (!io_busy) | |
163 | idle_time += get_cpu_iowait_time_us(cpu, wall); | |
164 | ||
165 | return idle_time; | |
166 | } | |
167 | EXPORT_SYMBOL_GPL(get_cpu_idle_time); | |
168 | ||
70e9e778 VK |
169 | /* |
170 | * This is a generic cpufreq init() routine which can be used by cpufreq | |
171 | * drivers of SMP systems. It will do following: | |
172 | * - validate & show freq table passed | |
173 | * - set policies transition latency | |
174 | * - policy->cpus with all possible CPUs | |
175 | */ | |
176 | int cpufreq_generic_init(struct cpufreq_policy *policy, | |
177 | struct cpufreq_frequency_table *table, | |
178 | unsigned int transition_latency) | |
179 | { | |
180 | int ret; | |
181 | ||
182 | ret = cpufreq_table_validate_and_show(policy, table); | |
183 | if (ret) { | |
184 | pr_err("%s: invalid frequency table: %d\n", __func__, ret); | |
185 | return ret; | |
186 | } | |
187 | ||
188 | policy->cpuinfo.transition_latency = transition_latency; | |
189 | ||
190 | /* | |
58405af6 | 191 | * The driver only supports the SMP configuration where all processors |
70e9e778 VK |
192 | * share the clock and voltage and clock. |
193 | */ | |
194 | cpumask_setall(policy->cpus); | |
195 | ||
196 | return 0; | |
197 | } | |
198 | EXPORT_SYMBOL_GPL(cpufreq_generic_init); | |
199 | ||
1f0bd44e | 200 | struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) |
652ed95d VK |
201 | { |
202 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
203 | ||
988bed09 VK |
204 | return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; |
205 | } | |
1f0bd44e | 206 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); |
988bed09 VK |
207 | |
208 | unsigned int cpufreq_generic_get(unsigned int cpu) | |
209 | { | |
210 | struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); | |
211 | ||
652ed95d | 212 | if (!policy || IS_ERR(policy->clk)) { |
e837f9b5 JP |
213 | pr_err("%s: No %s associated to cpu: %d\n", |
214 | __func__, policy ? "clk" : "policy", cpu); | |
652ed95d VK |
215 | return 0; |
216 | } | |
217 | ||
218 | return clk_get_rate(policy->clk) / 1000; | |
219 | } | |
220 | EXPORT_SYMBOL_GPL(cpufreq_generic_get); | |
221 | ||
50e9c852 VK |
222 | /** |
223 | * cpufreq_cpu_get: returns policy for a cpu and marks it busy. | |
224 | * | |
225 | * @cpu: cpu to find policy for. | |
226 | * | |
227 | * This returns policy for 'cpu', returns NULL if it doesn't exist. | |
228 | * It also increments the kobject reference count to mark it busy and so would | |
229 | * require a corresponding call to cpufreq_cpu_put() to decrement it back. | |
230 | * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be | |
231 | * freed as that depends on the kobj count. | |
232 | * | |
50e9c852 VK |
233 | * Return: A valid policy on success, otherwise NULL on failure. |
234 | */ | |
6eed9404 | 235 | struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) |
1da177e4 | 236 | { |
6eed9404 | 237 | struct cpufreq_policy *policy = NULL; |
1da177e4 LT |
238 | unsigned long flags; |
239 | ||
1b947c90 | 240 | if (WARN_ON(cpu >= nr_cpu_ids)) |
6eed9404 VK |
241 | return NULL; |
242 | ||
1da177e4 | 243 | /* get the cpufreq driver */ |
1c3d85dd | 244 | read_lock_irqsave(&cpufreq_driver_lock, flags); |
1da177e4 | 245 | |
6eed9404 VK |
246 | if (cpufreq_driver) { |
247 | /* get the CPU */ | |
988bed09 | 248 | policy = cpufreq_cpu_get_raw(cpu); |
6eed9404 VK |
249 | if (policy) |
250 | kobject_get(&policy->kobj); | |
251 | } | |
1da177e4 | 252 | |
6eed9404 | 253 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 254 | |
3a3e9e06 | 255 | return policy; |
a9144436 | 256 | } |
1da177e4 LT |
257 | EXPORT_SYMBOL_GPL(cpufreq_cpu_get); |
258 | ||
50e9c852 VK |
259 | /** |
260 | * cpufreq_cpu_put: Decrements the usage count of a policy | |
261 | * | |
262 | * @policy: policy earlier returned by cpufreq_cpu_get(). | |
263 | * | |
264 | * This decrements the kobject reference count incremented earlier by calling | |
265 | * cpufreq_cpu_get(). | |
50e9c852 | 266 | */ |
3a3e9e06 | 267 | void cpufreq_cpu_put(struct cpufreq_policy *policy) |
1da177e4 | 268 | { |
6eed9404 | 269 | kobject_put(&policy->kobj); |
1da177e4 LT |
270 | } |
271 | EXPORT_SYMBOL_GPL(cpufreq_cpu_put); | |
272 | ||
1da177e4 LT |
273 | /********************************************************************* |
274 | * EXTERNALLY AFFECTING FREQUENCY CHANGES * | |
275 | *********************************************************************/ | |
276 | ||
277 | /** | |
278 | * adjust_jiffies - adjust the system "loops_per_jiffy" | |
279 | * | |
280 | * This function alters the system "loops_per_jiffy" for the clock | |
281 | * speed change. Note that loops_per_jiffy cannot be updated on SMP | |
32ee8c3e | 282 | * systems as each CPU might be scaled differently. So, use the arch |
1da177e4 LT |
283 | * per-CPU loops_per_jiffy value wherever possible. |
284 | */ | |
858119e1 | 285 | static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) |
1da177e4 | 286 | { |
39c132ee VK |
287 | #ifndef CONFIG_SMP |
288 | static unsigned long l_p_j_ref; | |
289 | static unsigned int l_p_j_ref_freq; | |
290 | ||
1da177e4 LT |
291 | if (ci->flags & CPUFREQ_CONST_LOOPS) |
292 | return; | |
293 | ||
294 | if (!l_p_j_ref_freq) { | |
295 | l_p_j_ref = loops_per_jiffy; | |
296 | l_p_j_ref_freq = ci->old; | |
e837f9b5 JP |
297 | pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", |
298 | l_p_j_ref, l_p_j_ref_freq); | |
1da177e4 | 299 | } |
0b443ead | 300 | if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { |
e08f5f5b GS |
301 | loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, |
302 | ci->new); | |
e837f9b5 JP |
303 | pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", |
304 | loops_per_jiffy, ci->new); | |
1da177e4 | 305 | } |
1da177e4 | 306 | #endif |
39c132ee | 307 | } |
1da177e4 | 308 | |
0956df9c | 309 | static void __cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb | 310 | struct cpufreq_freqs *freqs, unsigned int state) |
1da177e4 LT |
311 | { |
312 | BUG_ON(irqs_disabled()); | |
313 | ||
d5aaffa9 DB |
314 | if (cpufreq_disabled()) |
315 | return; | |
316 | ||
1c3d85dd | 317 | freqs->flags = cpufreq_driver->flags; |
2d06d8c4 | 318 | pr_debug("notification %u of frequency transition to %u kHz\n", |
e837f9b5 | 319 | state, freqs->new); |
1da177e4 | 320 | |
1da177e4 | 321 | switch (state) { |
e4472cb3 | 322 | |
1da177e4 | 323 | case CPUFREQ_PRECHANGE: |
32ee8c3e | 324 | /* detect if the driver reported a value as "old frequency" |
e4472cb3 DJ |
325 | * which is not equal to what the cpufreq core thinks is |
326 | * "old frequency". | |
1da177e4 | 327 | */ |
1c3d85dd | 328 | if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e4472cb3 DJ |
329 | if ((policy) && (policy->cpu == freqs->cpu) && |
330 | (policy->cur) && (policy->cur != freqs->old)) { | |
e837f9b5 JP |
331 | pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", |
332 | freqs->old, policy->cur); | |
e4472cb3 | 333 | freqs->old = policy->cur; |
1da177e4 LT |
334 | } |
335 | } | |
b4dfdbb3 | 336 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 337 | CPUFREQ_PRECHANGE, freqs); |
1da177e4 LT |
338 | adjust_jiffies(CPUFREQ_PRECHANGE, freqs); |
339 | break; | |
e4472cb3 | 340 | |
1da177e4 LT |
341 | case CPUFREQ_POSTCHANGE: |
342 | adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); | |
e837f9b5 JP |
343 | pr_debug("FREQ: %lu - CPU: %lu\n", |
344 | (unsigned long)freqs->new, (unsigned long)freqs->cpu); | |
25e41933 | 345 | trace_cpu_frequency(freqs->new, freqs->cpu); |
b4dfdbb3 | 346 | srcu_notifier_call_chain(&cpufreq_transition_notifier_list, |
e041c683 | 347 | CPUFREQ_POSTCHANGE, freqs); |
e4472cb3 DJ |
348 | if (likely(policy) && likely(policy->cpu == freqs->cpu)) |
349 | policy->cur = freqs->new; | |
1da177e4 LT |
350 | break; |
351 | } | |
1da177e4 | 352 | } |
bb176f7d | 353 | |
b43a7ffb VK |
354 | /** |
355 | * cpufreq_notify_transition - call notifier chain and adjust_jiffies | |
356 | * on frequency transition. | |
357 | * | |
358 | * This function calls the transition notifiers and the "adjust_jiffies" | |
359 | * function. It is called twice on all CPU frequency changes that have | |
360 | * external effects. | |
361 | */ | |
236a9800 | 362 | static void cpufreq_notify_transition(struct cpufreq_policy *policy, |
b43a7ffb VK |
363 | struct cpufreq_freqs *freqs, unsigned int state) |
364 | { | |
365 | for_each_cpu(freqs->cpu, policy->cpus) | |
366 | __cpufreq_notify_transition(policy, freqs, state); | |
367 | } | |
1da177e4 | 368 | |
f7ba3b41 | 369 | /* Do post notifications when there are chances that transition has failed */ |
236a9800 | 370 | static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, |
f7ba3b41 VK |
371 | struct cpufreq_freqs *freqs, int transition_failed) |
372 | { | |
373 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
374 | if (!transition_failed) | |
375 | return; | |
376 | ||
377 | swap(freqs->old, freqs->new); | |
378 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
379 | cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); | |
380 | } | |
f7ba3b41 | 381 | |
12478cf0 SB |
382 | void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, |
383 | struct cpufreq_freqs *freqs) | |
384 | { | |
ca654dc3 SB |
385 | |
386 | /* | |
387 | * Catch double invocations of _begin() which lead to self-deadlock. | |
388 | * ASYNC_NOTIFICATION drivers are left out because the cpufreq core | |
389 | * doesn't invoke _begin() on their behalf, and hence the chances of | |
390 | * double invocations are very low. Moreover, there are scenarios | |
391 | * where these checks can emit false-positive warnings in these | |
392 | * drivers; so we avoid that by skipping them altogether. | |
393 | */ | |
394 | WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) | |
395 | && current == policy->transition_task); | |
396 | ||
12478cf0 SB |
397 | wait: |
398 | wait_event(policy->transition_wait, !policy->transition_ongoing); | |
399 | ||
400 | spin_lock(&policy->transition_lock); | |
401 | ||
402 | if (unlikely(policy->transition_ongoing)) { | |
403 | spin_unlock(&policy->transition_lock); | |
404 | goto wait; | |
405 | } | |
406 | ||
407 | policy->transition_ongoing = true; | |
ca654dc3 | 408 | policy->transition_task = current; |
12478cf0 SB |
409 | |
410 | spin_unlock(&policy->transition_lock); | |
411 | ||
412 | cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); | |
413 | } | |
414 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); | |
415 | ||
416 | void cpufreq_freq_transition_end(struct cpufreq_policy *policy, | |
417 | struct cpufreq_freqs *freqs, int transition_failed) | |
418 | { | |
419 | if (unlikely(WARN_ON(!policy->transition_ongoing))) | |
420 | return; | |
421 | ||
422 | cpufreq_notify_post_transition(policy, freqs, transition_failed); | |
423 | ||
424 | policy->transition_ongoing = false; | |
ca654dc3 | 425 | policy->transition_task = NULL; |
12478cf0 SB |
426 | |
427 | wake_up(&policy->transition_wait); | |
428 | } | |
429 | EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); | |
430 | ||
1da177e4 | 431 | |
1da177e4 LT |
432 | /********************************************************************* |
433 | * SYSFS INTERFACE * | |
434 | *********************************************************************/ | |
8a5c74a1 | 435 | static ssize_t show_boost(struct kobject *kobj, |
6f19efc0 LM |
436 | struct attribute *attr, char *buf) |
437 | { | |
438 | return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); | |
439 | } | |
440 | ||
441 | static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, | |
442 | const char *buf, size_t count) | |
443 | { | |
444 | int ret, enable; | |
445 | ||
446 | ret = sscanf(buf, "%d", &enable); | |
447 | if (ret != 1 || enable < 0 || enable > 1) | |
448 | return -EINVAL; | |
449 | ||
450 | if (cpufreq_boost_trigger_state(enable)) { | |
e837f9b5 JP |
451 | pr_err("%s: Cannot %s BOOST!\n", |
452 | __func__, enable ? "enable" : "disable"); | |
6f19efc0 LM |
453 | return -EINVAL; |
454 | } | |
455 | ||
e837f9b5 JP |
456 | pr_debug("%s: cpufreq BOOST %s\n", |
457 | __func__, enable ? "enabled" : "disabled"); | |
6f19efc0 LM |
458 | |
459 | return count; | |
460 | } | |
461 | define_one_global_rw(boost); | |
1da177e4 | 462 | |
42f91fa1 | 463 | static struct cpufreq_governor *find_governor(const char *str_governor) |
3bcb09a3 JF |
464 | { |
465 | struct cpufreq_governor *t; | |
466 | ||
f7b27061 | 467 | for_each_governor(t) |
7c4f4539 | 468 | if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) |
3bcb09a3 JF |
469 | return t; |
470 | ||
471 | return NULL; | |
472 | } | |
473 | ||
1da177e4 LT |
474 | /** |
475 | * cpufreq_parse_governor - parse a governor string | |
476 | */ | |
905d77cd | 477 | static int cpufreq_parse_governor(char *str_governor, unsigned int *policy, |
1da177e4 LT |
478 | struct cpufreq_governor **governor) |
479 | { | |
3bcb09a3 | 480 | int err = -EINVAL; |
1c3d85dd | 481 | |
1c3d85dd | 482 | if (cpufreq_driver->setpolicy) { |
7c4f4539 | 483 | if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { |
1da177e4 | 484 | *policy = CPUFREQ_POLICY_PERFORMANCE; |
3bcb09a3 | 485 | err = 0; |
7c4f4539 | 486 | } else if (!strncasecmp(str_governor, "powersave", |
e08f5f5b | 487 | CPUFREQ_NAME_LEN)) { |
1da177e4 | 488 | *policy = CPUFREQ_POLICY_POWERSAVE; |
3bcb09a3 | 489 | err = 0; |
1da177e4 | 490 | } |
2e1cc3a5 | 491 | } else { |
1da177e4 | 492 | struct cpufreq_governor *t; |
3bcb09a3 | 493 | |
3fc54d37 | 494 | mutex_lock(&cpufreq_governor_mutex); |
3bcb09a3 | 495 | |
42f91fa1 | 496 | t = find_governor(str_governor); |
3bcb09a3 | 497 | |
ea714970 | 498 | if (t == NULL) { |
1a8e1463 | 499 | int ret; |
ea714970 | 500 | |
1a8e1463 KC |
501 | mutex_unlock(&cpufreq_governor_mutex); |
502 | ret = request_module("cpufreq_%s", str_governor); | |
503 | mutex_lock(&cpufreq_governor_mutex); | |
ea714970 | 504 | |
1a8e1463 | 505 | if (ret == 0) |
42f91fa1 | 506 | t = find_governor(str_governor); |
ea714970 JF |
507 | } |
508 | ||
3bcb09a3 JF |
509 | if (t != NULL) { |
510 | *governor = t; | |
511 | err = 0; | |
1da177e4 | 512 | } |
3bcb09a3 | 513 | |
3fc54d37 | 514 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 | 515 | } |
3bcb09a3 | 516 | return err; |
1da177e4 | 517 | } |
1da177e4 | 518 | |
1da177e4 | 519 | /** |
e08f5f5b GS |
520 | * cpufreq_per_cpu_attr_read() / show_##file_name() - |
521 | * print out cpufreq information | |
1da177e4 LT |
522 | * |
523 | * Write out information from cpufreq_driver->policy[cpu]; object must be | |
524 | * "unsigned int". | |
525 | */ | |
526 | ||
32ee8c3e DJ |
527 | #define show_one(file_name, object) \ |
528 | static ssize_t show_##file_name \ | |
905d77cd | 529 | (struct cpufreq_policy *policy, char *buf) \ |
32ee8c3e | 530 | { \ |
29464f28 | 531 | return sprintf(buf, "%u\n", policy->object); \ |
1da177e4 LT |
532 | } |
533 | ||
534 | show_one(cpuinfo_min_freq, cpuinfo.min_freq); | |
535 | show_one(cpuinfo_max_freq, cpuinfo.max_freq); | |
ed129784 | 536 | show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); |
1da177e4 LT |
537 | show_one(scaling_min_freq, min); |
538 | show_one(scaling_max_freq, max); | |
c034b02e | 539 | |
09347b29 | 540 | static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) |
c034b02e DB |
541 | { |
542 | ssize_t ret; | |
543 | ||
544 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) | |
545 | ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); | |
546 | else | |
547 | ret = sprintf(buf, "%u\n", policy->cur); | |
548 | return ret; | |
549 | } | |
1da177e4 | 550 | |
037ce839 | 551 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 552 | struct cpufreq_policy *new_policy); |
7970e08b | 553 | |
1da177e4 LT |
554 | /** |
555 | * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access | |
556 | */ | |
557 | #define store_one(file_name, object) \ | |
558 | static ssize_t store_##file_name \ | |
905d77cd | 559 | (struct cpufreq_policy *policy, const char *buf, size_t count) \ |
1da177e4 | 560 | { \ |
619c144c | 561 | int ret, temp; \ |
1da177e4 LT |
562 | struct cpufreq_policy new_policy; \ |
563 | \ | |
8fa5b631 | 564 | memcpy(&new_policy, policy, sizeof(*policy)); \ |
1da177e4 | 565 | \ |
29464f28 | 566 | ret = sscanf(buf, "%u", &new_policy.object); \ |
1da177e4 LT |
567 | if (ret != 1) \ |
568 | return -EINVAL; \ | |
569 | \ | |
619c144c | 570 | temp = new_policy.object; \ |
037ce839 | 571 | ret = cpufreq_set_policy(policy, &new_policy); \ |
619c144c VH |
572 | if (!ret) \ |
573 | policy->user_policy.object = temp; \ | |
1da177e4 LT |
574 | \ |
575 | return ret ? ret : count; \ | |
576 | } | |
577 | ||
29464f28 DJ |
578 | store_one(scaling_min_freq, min); |
579 | store_one(scaling_max_freq, max); | |
1da177e4 LT |
580 | |
581 | /** | |
582 | * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware | |
583 | */ | |
905d77cd DJ |
584 | static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, |
585 | char *buf) | |
1da177e4 | 586 | { |
d92d50a4 | 587 | unsigned int cur_freq = __cpufreq_get(policy); |
1da177e4 LT |
588 | if (!cur_freq) |
589 | return sprintf(buf, "<unknown>"); | |
590 | return sprintf(buf, "%u\n", cur_freq); | |
591 | } | |
592 | ||
1da177e4 LT |
593 | /** |
594 | * show_scaling_governor - show the current policy for the specified CPU | |
595 | */ | |
905d77cd | 596 | static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 597 | { |
29464f28 | 598 | if (policy->policy == CPUFREQ_POLICY_POWERSAVE) |
1da177e4 LT |
599 | return sprintf(buf, "powersave\n"); |
600 | else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) | |
601 | return sprintf(buf, "performance\n"); | |
602 | else if (policy->governor) | |
4b972f0b | 603 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", |
29464f28 | 604 | policy->governor->name); |
1da177e4 LT |
605 | return -EINVAL; |
606 | } | |
607 | ||
1da177e4 LT |
608 | /** |
609 | * store_scaling_governor - store policy for the specified CPU | |
610 | */ | |
905d77cd DJ |
611 | static ssize_t store_scaling_governor(struct cpufreq_policy *policy, |
612 | const char *buf, size_t count) | |
1da177e4 | 613 | { |
5136fa56 | 614 | int ret; |
1da177e4 LT |
615 | char str_governor[16]; |
616 | struct cpufreq_policy new_policy; | |
617 | ||
8fa5b631 | 618 | memcpy(&new_policy, policy, sizeof(*policy)); |
1da177e4 | 619 | |
29464f28 | 620 | ret = sscanf(buf, "%15s", str_governor); |
1da177e4 LT |
621 | if (ret != 1) |
622 | return -EINVAL; | |
623 | ||
e08f5f5b GS |
624 | if (cpufreq_parse_governor(str_governor, &new_policy.policy, |
625 | &new_policy.governor)) | |
1da177e4 LT |
626 | return -EINVAL; |
627 | ||
037ce839 | 628 | ret = cpufreq_set_policy(policy, &new_policy); |
88dc4384 | 629 | return ret ? ret : count; |
1da177e4 LT |
630 | } |
631 | ||
632 | /** | |
633 | * show_scaling_driver - show the cpufreq driver currently loaded | |
634 | */ | |
905d77cd | 635 | static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 636 | { |
1c3d85dd | 637 | return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); |
1da177e4 LT |
638 | } |
639 | ||
640 | /** | |
641 | * show_scaling_available_governors - show the available CPUfreq governors | |
642 | */ | |
905d77cd DJ |
643 | static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, |
644 | char *buf) | |
1da177e4 LT |
645 | { |
646 | ssize_t i = 0; | |
647 | struct cpufreq_governor *t; | |
648 | ||
9c0ebcf7 | 649 | if (!has_target()) { |
1da177e4 LT |
650 | i += sprintf(buf, "performance powersave"); |
651 | goto out; | |
652 | } | |
653 | ||
f7b27061 | 654 | for_each_governor(t) { |
29464f28 DJ |
655 | if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) |
656 | - (CPUFREQ_NAME_LEN + 2))) | |
1da177e4 | 657 | goto out; |
4b972f0b | 658 | i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); |
1da177e4 | 659 | } |
7d5e350f | 660 | out: |
1da177e4 LT |
661 | i += sprintf(&buf[i], "\n"); |
662 | return i; | |
663 | } | |
e8628dd0 | 664 | |
f4fd3797 | 665 | ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) |
1da177e4 LT |
666 | { |
667 | ssize_t i = 0; | |
668 | unsigned int cpu; | |
669 | ||
835481d9 | 670 | for_each_cpu(cpu, mask) { |
1da177e4 LT |
671 | if (i) |
672 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); | |
673 | i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); | |
674 | if (i >= (PAGE_SIZE - 5)) | |
29464f28 | 675 | break; |
1da177e4 LT |
676 | } |
677 | i += sprintf(&buf[i], "\n"); | |
678 | return i; | |
679 | } | |
f4fd3797 | 680 | EXPORT_SYMBOL_GPL(cpufreq_show_cpus); |
1da177e4 | 681 | |
e8628dd0 DW |
682 | /** |
683 | * show_related_cpus - show the CPUs affected by each transition even if | |
684 | * hw coordination is in use | |
685 | */ | |
686 | static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) | |
687 | { | |
f4fd3797 | 688 | return cpufreq_show_cpus(policy->related_cpus, buf); |
e8628dd0 DW |
689 | } |
690 | ||
691 | /** | |
692 | * show_affected_cpus - show the CPUs affected by each transition | |
693 | */ | |
694 | static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) | |
695 | { | |
f4fd3797 | 696 | return cpufreq_show_cpus(policy->cpus, buf); |
e8628dd0 DW |
697 | } |
698 | ||
9e76988e | 699 | static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, |
905d77cd | 700 | const char *buf, size_t count) |
9e76988e VP |
701 | { |
702 | unsigned int freq = 0; | |
703 | unsigned int ret; | |
704 | ||
879000f9 | 705 | if (!policy->governor || !policy->governor->store_setspeed) |
9e76988e VP |
706 | return -EINVAL; |
707 | ||
708 | ret = sscanf(buf, "%u", &freq); | |
709 | if (ret != 1) | |
710 | return -EINVAL; | |
711 | ||
712 | policy->governor->store_setspeed(policy, freq); | |
713 | ||
714 | return count; | |
715 | } | |
716 | ||
717 | static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) | |
718 | { | |
879000f9 | 719 | if (!policy->governor || !policy->governor->show_setspeed) |
9e76988e VP |
720 | return sprintf(buf, "<unsupported>\n"); |
721 | ||
722 | return policy->governor->show_setspeed(policy, buf); | |
723 | } | |
1da177e4 | 724 | |
e2f74f35 | 725 | /** |
8bf1ac72 | 726 | * show_bios_limit - show the current cpufreq HW/BIOS limitation |
e2f74f35 TR |
727 | */ |
728 | static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) | |
729 | { | |
730 | unsigned int limit; | |
731 | int ret; | |
1c3d85dd RW |
732 | if (cpufreq_driver->bios_limit) { |
733 | ret = cpufreq_driver->bios_limit(policy->cpu, &limit); | |
e2f74f35 TR |
734 | if (!ret) |
735 | return sprintf(buf, "%u\n", limit); | |
736 | } | |
737 | return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); | |
738 | } | |
739 | ||
6dad2a29 BP |
740 | cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); |
741 | cpufreq_freq_attr_ro(cpuinfo_min_freq); | |
742 | cpufreq_freq_attr_ro(cpuinfo_max_freq); | |
743 | cpufreq_freq_attr_ro(cpuinfo_transition_latency); | |
744 | cpufreq_freq_attr_ro(scaling_available_governors); | |
745 | cpufreq_freq_attr_ro(scaling_driver); | |
746 | cpufreq_freq_attr_ro(scaling_cur_freq); | |
747 | cpufreq_freq_attr_ro(bios_limit); | |
748 | cpufreq_freq_attr_ro(related_cpus); | |
749 | cpufreq_freq_attr_ro(affected_cpus); | |
750 | cpufreq_freq_attr_rw(scaling_min_freq); | |
751 | cpufreq_freq_attr_rw(scaling_max_freq); | |
752 | cpufreq_freq_attr_rw(scaling_governor); | |
753 | cpufreq_freq_attr_rw(scaling_setspeed); | |
1da177e4 | 754 | |
905d77cd | 755 | static struct attribute *default_attrs[] = { |
1da177e4 LT |
756 | &cpuinfo_min_freq.attr, |
757 | &cpuinfo_max_freq.attr, | |
ed129784 | 758 | &cpuinfo_transition_latency.attr, |
1da177e4 LT |
759 | &scaling_min_freq.attr, |
760 | &scaling_max_freq.attr, | |
761 | &affected_cpus.attr, | |
e8628dd0 | 762 | &related_cpus.attr, |
1da177e4 LT |
763 | &scaling_governor.attr, |
764 | &scaling_driver.attr, | |
765 | &scaling_available_governors.attr, | |
9e76988e | 766 | &scaling_setspeed.attr, |
1da177e4 LT |
767 | NULL |
768 | }; | |
769 | ||
29464f28 DJ |
770 | #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) |
771 | #define to_attr(a) container_of(a, struct freq_attr, attr) | |
1da177e4 | 772 | |
29464f28 | 773 | static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) |
1da177e4 | 774 | { |
905d77cd DJ |
775 | struct cpufreq_policy *policy = to_policy(kobj); |
776 | struct freq_attr *fattr = to_attr(attr); | |
1b750e3b | 777 | ssize_t ret; |
6eed9404 | 778 | |
ad7722da | 779 | down_read(&policy->rwsem); |
6541aef0 | 780 | ret = fattr->show(policy, buf); |
ad7722da | 781 | up_read(&policy->rwsem); |
1b750e3b | 782 | |
1da177e4 LT |
783 | return ret; |
784 | } | |
785 | ||
905d77cd DJ |
786 | static ssize_t store(struct kobject *kobj, struct attribute *attr, |
787 | const char *buf, size_t count) | |
1da177e4 | 788 | { |
905d77cd DJ |
789 | struct cpufreq_policy *policy = to_policy(kobj); |
790 | struct freq_attr *fattr = to_attr(attr); | |
a07530b4 | 791 | ssize_t ret = -EINVAL; |
6eed9404 | 792 | |
4f750c93 SB |
793 | get_online_cpus(); |
794 | ||
6541aef0 RW |
795 | if (cpu_online(policy->cpu)) { |
796 | down_write(&policy->rwsem); | |
e08f5f5b | 797 | ret = fattr->store(policy, buf, count); |
6541aef0 RW |
798 | up_write(&policy->rwsem); |
799 | } | |
e08f5f5b | 800 | |
4f750c93 SB |
801 | put_online_cpus(); |
802 | ||
1da177e4 LT |
803 | return ret; |
804 | } | |
805 | ||
905d77cd | 806 | static void cpufreq_sysfs_release(struct kobject *kobj) |
1da177e4 | 807 | { |
905d77cd | 808 | struct cpufreq_policy *policy = to_policy(kobj); |
2d06d8c4 | 809 | pr_debug("last reference is dropped\n"); |
1da177e4 LT |
810 | complete(&policy->kobj_unregister); |
811 | } | |
812 | ||
52cf25d0 | 813 | static const struct sysfs_ops sysfs_ops = { |
1da177e4 LT |
814 | .show = show, |
815 | .store = store, | |
816 | }; | |
817 | ||
818 | static struct kobj_type ktype_cpufreq = { | |
819 | .sysfs_ops = &sysfs_ops, | |
820 | .default_attrs = default_attrs, | |
821 | .release = cpufreq_sysfs_release, | |
822 | }; | |
823 | ||
87549141 VK |
824 | static int add_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) |
825 | { | |
826 | struct device *cpu_dev; | |
827 | ||
828 | pr_debug("%s: Adding symlink for CPU: %u\n", __func__, cpu); | |
829 | ||
830 | if (!policy) | |
831 | return 0; | |
832 | ||
833 | cpu_dev = get_cpu_device(cpu); | |
834 | if (WARN_ON(!cpu_dev)) | |
835 | return 0; | |
836 | ||
837 | return sysfs_create_link(&cpu_dev->kobj, &policy->kobj, "cpufreq"); | |
838 | } | |
839 | ||
840 | static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, int cpu) | |
841 | { | |
842 | struct device *cpu_dev; | |
843 | ||
844 | pr_debug("%s: Removing symlink for CPU: %u\n", __func__, cpu); | |
845 | ||
846 | cpu_dev = get_cpu_device(cpu); | |
847 | if (WARN_ON(!cpu_dev)) | |
848 | return; | |
849 | ||
850 | sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); | |
851 | } | |
852 | ||
853 | /* Add/remove symlinks for all related CPUs */ | |
308b60e7 | 854 | static int cpufreq_add_dev_symlink(struct cpufreq_policy *policy) |
19d6f7ec DJ |
855 | { |
856 | unsigned int j; | |
857 | int ret = 0; | |
858 | ||
87549141 | 859 | /* Some related CPUs might not be present (physically hotplugged) */ |
559ed407 | 860 | for_each_cpu(j, policy->real_cpus) { |
87549141 | 861 | ret = add_cpu_dev_symlink(policy, j); |
71c3461e RW |
862 | if (ret) |
863 | break; | |
19d6f7ec | 864 | } |
87549141 | 865 | |
19d6f7ec DJ |
866 | return ret; |
867 | } | |
868 | ||
87549141 VK |
869 | static void cpufreq_remove_dev_symlink(struct cpufreq_policy *policy) |
870 | { | |
871 | unsigned int j; | |
872 | ||
873 | /* Some related CPUs might not be present (physically hotplugged) */ | |
96bdda61 | 874 | for_each_cpu(j, policy->real_cpus) |
87549141 | 875 | remove_cpu_dev_symlink(policy, j); |
87549141 VK |
876 | } |
877 | ||
d9612a49 | 878 | static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) |
909a694e DJ |
879 | { |
880 | struct freq_attr **drv_attr; | |
909a694e | 881 | int ret = 0; |
909a694e | 882 | |
909a694e | 883 | /* set up files for this cpu device */ |
1c3d85dd | 884 | drv_attr = cpufreq_driver->attr; |
f13f1184 | 885 | while (drv_attr && *drv_attr) { |
909a694e DJ |
886 | ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); |
887 | if (ret) | |
6d4e81ed | 888 | return ret; |
909a694e DJ |
889 | drv_attr++; |
890 | } | |
1c3d85dd | 891 | if (cpufreq_driver->get) { |
909a694e DJ |
892 | ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); |
893 | if (ret) | |
6d4e81ed | 894 | return ret; |
909a694e | 895 | } |
c034b02e DB |
896 | |
897 | ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); | |
898 | if (ret) | |
6d4e81ed | 899 | return ret; |
c034b02e | 900 | |
1c3d85dd | 901 | if (cpufreq_driver->bios_limit) { |
e2f74f35 TR |
902 | ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); |
903 | if (ret) | |
6d4e81ed | 904 | return ret; |
e2f74f35 | 905 | } |
909a694e | 906 | |
6d4e81ed | 907 | return cpufreq_add_dev_symlink(policy); |
e18f1682 SB |
908 | } |
909 | ||
de1df26b RW |
910 | __weak struct cpufreq_governor *cpufreq_default_governor(void) |
911 | { | |
912 | return NULL; | |
913 | } | |
914 | ||
7f0fa40f | 915 | static int cpufreq_init_policy(struct cpufreq_policy *policy) |
e18f1682 | 916 | { |
6e2c89d1 | 917 | struct cpufreq_governor *gov = NULL; |
e18f1682 | 918 | struct cpufreq_policy new_policy; |
e18f1682 | 919 | |
d5b73cd8 | 920 | memcpy(&new_policy, policy, sizeof(*policy)); |
a27a9ab7 | 921 | |
6e2c89d1 | 922 | /* Update governor of new_policy to the governor used before hotplug */ |
4573237b | 923 | gov = find_governor(policy->last_governor); |
de1df26b | 924 | if (gov) { |
6e2c89d1 | 925 | pr_debug("Restoring governor %s for cpu %d\n", |
926 | policy->governor->name, policy->cpu); | |
de1df26b RW |
927 | } else { |
928 | gov = cpufreq_default_governor(); | |
929 | if (!gov) | |
930 | return -ENODATA; | |
931 | } | |
6e2c89d1 | 932 | |
933 | new_policy.governor = gov; | |
934 | ||
69030dd1 SP |
935 | /* Use the default policy if there is no last_policy. */ |
936 | if (cpufreq_driver->setpolicy) { | |
937 | if (policy->last_policy) | |
938 | new_policy.policy = policy->last_policy; | |
939 | else | |
940 | cpufreq_parse_governor(gov->name, &new_policy.policy, | |
941 | NULL); | |
942 | } | |
ecf7e461 | 943 | /* set default policy */ |
7f0fa40f | 944 | return cpufreq_set_policy(policy, &new_policy); |
909a694e DJ |
945 | } |
946 | ||
d9612a49 | 947 | static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) |
fcf80582 | 948 | { |
9c0ebcf7 | 949 | int ret = 0; |
fcf80582 | 950 | |
bb29ae15 VK |
951 | /* Has this CPU been taken care of already? */ |
952 | if (cpumask_test_cpu(cpu, policy->cpus)) | |
953 | return 0; | |
954 | ||
49f18560 | 955 | down_write(&policy->rwsem); |
9c0ebcf7 | 956 | if (has_target()) { |
a1317e09 | 957 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
3de9bdeb VK |
958 | if (ret) { |
959 | pr_err("%s: Failed to stop governor\n", __func__); | |
49f18560 | 960 | goto unlock; |
3de9bdeb VK |
961 | } |
962 | } | |
fcf80582 | 963 | |
fcf80582 | 964 | cpumask_set_cpu(cpu, policy->cpus); |
2eaa3e2d | 965 | |
9c0ebcf7 | 966 | if (has_target()) { |
a1317e09 | 967 | ret = cpufreq_governor(policy, CPUFREQ_GOV_START); |
e5c87b76 | 968 | if (!ret) |
a1317e09 | 969 | ret = cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
e5c87b76 | 970 | |
49f18560 | 971 | if (ret) |
3de9bdeb | 972 | pr_err("%s: Failed to start governor\n", __func__); |
820c6ca2 | 973 | } |
fcf80582 | 974 | |
49f18560 VK |
975 | unlock: |
976 | up_write(&policy->rwsem); | |
977 | return ret; | |
fcf80582 | 978 | } |
1da177e4 | 979 | |
11eb69b9 VK |
980 | static void handle_update(struct work_struct *work) |
981 | { | |
982 | struct cpufreq_policy *policy = | |
983 | container_of(work, struct cpufreq_policy, update); | |
984 | unsigned int cpu = policy->cpu; | |
985 | pr_debug("handle_update for cpu %u called\n", cpu); | |
986 | cpufreq_update_policy(cpu); | |
fcf80582 | 987 | } |
1da177e4 | 988 | |
a34e63b1 | 989 | static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) |
e9698cc5 | 990 | { |
a34e63b1 | 991 | struct device *dev = get_cpu_device(cpu); |
e9698cc5 | 992 | struct cpufreq_policy *policy; |
edd4a893 | 993 | int ret; |
e9698cc5 | 994 | |
a34e63b1 RW |
995 | if (WARN_ON(!dev)) |
996 | return NULL; | |
997 | ||
e9698cc5 SB |
998 | policy = kzalloc(sizeof(*policy), GFP_KERNEL); |
999 | if (!policy) | |
1000 | return NULL; | |
1001 | ||
1002 | if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) | |
1003 | goto err_free_policy; | |
1004 | ||
1005 | if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) | |
1006 | goto err_free_cpumask; | |
1007 | ||
559ed407 RW |
1008 | if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) |
1009 | goto err_free_rcpumask; | |
1010 | ||
edd4a893 VK |
1011 | ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, |
1012 | cpufreq_global_kobject, "policy%u", cpu); | |
1013 | if (ret) { | |
1014 | pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); | |
1015 | goto err_free_real_cpus; | |
1016 | } | |
1017 | ||
c88a1f8b | 1018 | INIT_LIST_HEAD(&policy->policy_list); |
ad7722da | 1019 | init_rwsem(&policy->rwsem); |
12478cf0 SB |
1020 | spin_lock_init(&policy->transition_lock); |
1021 | init_waitqueue_head(&policy->transition_wait); | |
818c5712 VK |
1022 | init_completion(&policy->kobj_unregister); |
1023 | INIT_WORK(&policy->update, handle_update); | |
ad7722da | 1024 | |
a34e63b1 | 1025 | policy->cpu = cpu; |
e9698cc5 SB |
1026 | return policy; |
1027 | ||
edd4a893 VK |
1028 | err_free_real_cpus: |
1029 | free_cpumask_var(policy->real_cpus); | |
2fc3384d VK |
1030 | err_free_rcpumask: |
1031 | free_cpumask_var(policy->related_cpus); | |
e9698cc5 SB |
1032 | err_free_cpumask: |
1033 | free_cpumask_var(policy->cpus); | |
1034 | err_free_policy: | |
1035 | kfree(policy); | |
1036 | ||
1037 | return NULL; | |
1038 | } | |
1039 | ||
2fc3384d | 1040 | static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify) |
42f921a6 VK |
1041 | { |
1042 | struct kobject *kobj; | |
1043 | struct completion *cmp; | |
1044 | ||
2fc3384d VK |
1045 | if (notify) |
1046 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, | |
1047 | CPUFREQ_REMOVE_POLICY, policy); | |
fcd7af91 | 1048 | |
87549141 VK |
1049 | down_write(&policy->rwsem); |
1050 | cpufreq_remove_dev_symlink(policy); | |
42f921a6 VK |
1051 | kobj = &policy->kobj; |
1052 | cmp = &policy->kobj_unregister; | |
87549141 | 1053 | up_write(&policy->rwsem); |
42f921a6 VK |
1054 | kobject_put(kobj); |
1055 | ||
1056 | /* | |
1057 | * We need to make sure that the underlying kobj is | |
1058 | * actually not referenced anymore by anybody before we | |
1059 | * proceed with unloading. | |
1060 | */ | |
1061 | pr_debug("waiting for dropping of refcount\n"); | |
1062 | wait_for_completion(cmp); | |
1063 | pr_debug("wait complete\n"); | |
1064 | } | |
1065 | ||
3654c5cc | 1066 | static void cpufreq_policy_free(struct cpufreq_policy *policy, bool notify) |
e9698cc5 | 1067 | { |
988bed09 VK |
1068 | unsigned long flags; |
1069 | int cpu; | |
1070 | ||
1071 | /* Remove policy from list */ | |
1072 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
1073 | list_del(&policy->policy_list); | |
1074 | ||
1075 | for_each_cpu(cpu, policy->related_cpus) | |
1076 | per_cpu(cpufreq_cpu_data, cpu) = NULL; | |
1077 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1078 | ||
3654c5cc | 1079 | cpufreq_policy_put_kobj(policy, notify); |
559ed407 | 1080 | free_cpumask_var(policy->real_cpus); |
e9698cc5 SB |
1081 | free_cpumask_var(policy->related_cpus); |
1082 | free_cpumask_var(policy->cpus); | |
1083 | kfree(policy); | |
1084 | } | |
1085 | ||
0b275352 | 1086 | static int cpufreq_online(unsigned int cpu) |
1da177e4 | 1087 | { |
7f0c020a | 1088 | struct cpufreq_policy *policy; |
194d99c7 | 1089 | bool new_policy; |
1da177e4 | 1090 | unsigned long flags; |
0b275352 RW |
1091 | unsigned int j; |
1092 | int ret; | |
87549141 | 1093 | |
0b275352 | 1094 | pr_debug("%s: bringing CPU%u online\n", __func__, cpu); |
6eed9404 | 1095 | |
bb29ae15 | 1096 | /* Check if this CPU already has a policy to manage it */ |
9104bb26 | 1097 | policy = per_cpu(cpufreq_cpu_data, cpu); |
11ce707e | 1098 | if (policy) { |
9104bb26 | 1099 | WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); |
11ce707e | 1100 | if (!policy_is_inactive(policy)) |
d9612a49 | 1101 | return cpufreq_add_policy_cpu(policy, cpu); |
1da177e4 | 1102 | |
11ce707e | 1103 | /* This is the only online CPU for the policy. Start over. */ |
194d99c7 | 1104 | new_policy = false; |
11ce707e RW |
1105 | down_write(&policy->rwsem); |
1106 | policy->cpu = cpu; | |
1107 | policy->governor = NULL; | |
1108 | up_write(&policy->rwsem); | |
1109 | } else { | |
194d99c7 | 1110 | new_policy = true; |
a34e63b1 | 1111 | policy = cpufreq_policy_alloc(cpu); |
72368d12 | 1112 | if (!policy) |
d4d854d6 | 1113 | return -ENOMEM; |
72368d12 | 1114 | } |
0d66b91e | 1115 | |
835481d9 | 1116 | cpumask_copy(policy->cpus, cpumask_of(cpu)); |
1da177e4 | 1117 | |
1da177e4 LT |
1118 | /* call driver. From then on the cpufreq must be able |
1119 | * to accept all calls to ->verify and ->setpolicy for this CPU | |
1120 | */ | |
1c3d85dd | 1121 | ret = cpufreq_driver->init(policy); |
1da177e4 | 1122 | if (ret) { |
2d06d8c4 | 1123 | pr_debug("initialization failed\n"); |
8101f997 | 1124 | goto out_free_policy; |
1da177e4 | 1125 | } |
643ae6e8 | 1126 | |
6d4e81ed TV |
1127 | down_write(&policy->rwsem); |
1128 | ||
194d99c7 | 1129 | if (new_policy) { |
4d1f3a5b | 1130 | /* related_cpus should at least include policy->cpus. */ |
0998a03a | 1131 | cpumask_copy(policy->related_cpus, policy->cpus); |
4d1f3a5b | 1132 | /* Remember CPUs present at the policy creation time. */ |
559ed407 | 1133 | cpumask_and(policy->real_cpus, policy->cpus, cpu_present_mask); |
4d1f3a5b | 1134 | } |
559ed407 | 1135 | |
5a7e56a5 VK |
1136 | /* |
1137 | * affected cpus must always be the one, which are online. We aren't | |
1138 | * managing offline cpus here. | |
1139 | */ | |
1140 | cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); | |
1141 | ||
194d99c7 | 1142 | if (new_policy) { |
5a7e56a5 VK |
1143 | policy->user_policy.min = policy->min; |
1144 | policy->user_policy.max = policy->max; | |
6d4e81ed | 1145 | |
988bed09 VK |
1146 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1147 | for_each_cpu(j, policy->related_cpus) | |
1148 | per_cpu(cpufreq_cpu_data, j) = policy; | |
1149 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1150 | } | |
652ed95d | 1151 | |
2ed99e39 | 1152 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
da60ce9f VK |
1153 | policy->cur = cpufreq_driver->get(policy->cpu); |
1154 | if (!policy->cur) { | |
1155 | pr_err("%s: ->get() failed\n", __func__); | |
8101f997 | 1156 | goto out_exit_policy; |
da60ce9f VK |
1157 | } |
1158 | } | |
1159 | ||
d3916691 VK |
1160 | /* |
1161 | * Sometimes boot loaders set CPU frequency to a value outside of | |
1162 | * frequency table present with cpufreq core. In such cases CPU might be | |
1163 | * unstable if it has to run on that frequency for long duration of time | |
1164 | * and so its better to set it to a frequency which is specified in | |
1165 | * freq-table. This also makes cpufreq stats inconsistent as | |
1166 | * cpufreq-stats would fail to register because current frequency of CPU | |
1167 | * isn't found in freq-table. | |
1168 | * | |
1169 | * Because we don't want this change to effect boot process badly, we go | |
1170 | * for the next freq which is >= policy->cur ('cur' must be set by now, | |
1171 | * otherwise we will end up setting freq to lowest of the table as 'cur' | |
1172 | * is initialized to zero). | |
1173 | * | |
1174 | * We are passing target-freq as "policy->cur - 1" otherwise | |
1175 | * __cpufreq_driver_target() would simply fail, as policy->cur will be | |
1176 | * equal to target-freq. | |
1177 | */ | |
1178 | if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) | |
1179 | && has_target()) { | |
1180 | /* Are we running at unknown frequency ? */ | |
1181 | ret = cpufreq_frequency_table_get_index(policy, policy->cur); | |
1182 | if (ret == -EINVAL) { | |
1183 | /* Warn user and fix it */ | |
1184 | pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", | |
1185 | __func__, policy->cpu, policy->cur); | |
1186 | ret = __cpufreq_driver_target(policy, policy->cur - 1, | |
1187 | CPUFREQ_RELATION_L); | |
1188 | ||
1189 | /* | |
1190 | * Reaching here after boot in a few seconds may not | |
1191 | * mean that system will remain stable at "unknown" | |
1192 | * frequency for longer duration. Hence, a BUG_ON(). | |
1193 | */ | |
1194 | BUG_ON(ret); | |
1195 | pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", | |
1196 | __func__, policy->cpu, policy->cur); | |
1197 | } | |
1198 | } | |
1199 | ||
a1531acd TR |
1200 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1201 | CPUFREQ_START, policy); | |
1202 | ||
194d99c7 | 1203 | if (new_policy) { |
d9612a49 | 1204 | ret = cpufreq_add_dev_interface(policy); |
a82fab29 | 1205 | if (ret) |
8101f997 | 1206 | goto out_exit_policy; |
fcd7af91 VK |
1207 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
1208 | CPUFREQ_CREATE_POLICY, policy); | |
8ff69732 | 1209 | |
988bed09 VK |
1210 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1211 | list_add(&policy->policy_list, &cpufreq_policy_list); | |
1212 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
1213 | } | |
9515f4d6 | 1214 | |
7f0fa40f VK |
1215 | ret = cpufreq_init_policy(policy); |
1216 | if (ret) { | |
1217 | pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", | |
1218 | __func__, cpu, ret); | |
194d99c7 RW |
1219 | /* cpufreq_policy_free() will notify based on this */ |
1220 | new_policy = false; | |
1221 | goto out_exit_policy; | |
08fd8c1c | 1222 | } |
e18f1682 | 1223 | |
4e97b631 | 1224 | up_write(&policy->rwsem); |
08fd8c1c | 1225 | |
038c5b3e | 1226 | kobject_uevent(&policy->kobj, KOBJ_ADD); |
7c45cf31 | 1227 | |
7c45cf31 VK |
1228 | /* Callback for handling stuff after policy is ready */ |
1229 | if (cpufreq_driver->ready) | |
1230 | cpufreq_driver->ready(policy); | |
1231 | ||
2d06d8c4 | 1232 | pr_debug("initialization complete\n"); |
87c32271 | 1233 | |
1da177e4 LT |
1234 | return 0; |
1235 | ||
8101f997 | 1236 | out_exit_policy: |
7106e02b PB |
1237 | up_write(&policy->rwsem); |
1238 | ||
da60ce9f VK |
1239 | if (cpufreq_driver->exit) |
1240 | cpufreq_driver->exit(policy); | |
8101f997 | 1241 | out_free_policy: |
194d99c7 | 1242 | cpufreq_policy_free(policy, !new_policy); |
1da177e4 LT |
1243 | return ret; |
1244 | } | |
1245 | ||
0b275352 RW |
1246 | /** |
1247 | * cpufreq_add_dev - the cpufreq interface for a CPU device. | |
1248 | * @dev: CPU device. | |
1249 | * @sif: Subsystem interface structure pointer (not used) | |
1250 | */ | |
1251 | static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) | |
1252 | { | |
1253 | unsigned cpu = dev->id; | |
1254 | int ret; | |
1255 | ||
1256 | dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); | |
1257 | ||
1258 | if (cpu_online(cpu)) { | |
1259 | ret = cpufreq_online(cpu); | |
1260 | } else { | |
1261 | /* | |
1262 | * A hotplug notifier will follow and we will handle it as CPU | |
1263 | * online then. For now, just create the sysfs link, unless | |
1264 | * there is no policy or the link is already present. | |
1265 | */ | |
1266 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); | |
1267 | ||
1268 | ret = policy && !cpumask_test_and_set_cpu(cpu, policy->real_cpus) | |
1269 | ? add_cpu_dev_symlink(policy, cpu) : 0; | |
1270 | } | |
6eed9404 | 1271 | |
1da177e4 LT |
1272 | return ret; |
1273 | } | |
1274 | ||
69cee714 | 1275 | static void cpufreq_offline(unsigned int cpu) |
1da177e4 | 1276 | { |
3a3e9e06 | 1277 | struct cpufreq_policy *policy; |
69cee714 | 1278 | int ret; |
1da177e4 | 1279 | |
b8eed8af | 1280 | pr_debug("%s: unregistering CPU %u\n", __func__, cpu); |
1da177e4 | 1281 | |
988bed09 | 1282 | policy = cpufreq_cpu_get_raw(cpu); |
3a3e9e06 | 1283 | if (!policy) { |
b8eed8af | 1284 | pr_debug("%s: No cpu_data found\n", __func__); |
15c0b4d2 | 1285 | return; |
1da177e4 | 1286 | } |
1da177e4 | 1287 | |
49f18560 | 1288 | down_write(&policy->rwsem); |
9c0ebcf7 | 1289 | if (has_target()) { |
a1317e09 | 1290 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
559ed407 | 1291 | if (ret) |
3de9bdeb | 1292 | pr_err("%s: Failed to stop governor\n", __func__); |
db5f2995 | 1293 | } |
1da177e4 | 1294 | |
9591becb | 1295 | cpumask_clear_cpu(cpu, policy->cpus); |
4573237b | 1296 | |
9591becb VK |
1297 | if (policy_is_inactive(policy)) { |
1298 | if (has_target()) | |
1299 | strncpy(policy->last_governor, policy->governor->name, | |
1300 | CPUFREQ_NAME_LEN); | |
69030dd1 SP |
1301 | else |
1302 | policy->last_policy = policy->policy; | |
9591becb VK |
1303 | } else if (cpu == policy->cpu) { |
1304 | /* Nominate new CPU */ | |
1305 | policy->cpu = cpumask_any(policy->cpus); | |
1306 | } | |
084f3493 | 1307 | |
9591becb VK |
1308 | /* Start governor again for active policy */ |
1309 | if (!policy_is_inactive(policy)) { | |
1310 | if (has_target()) { | |
a1317e09 | 1311 | ret = cpufreq_governor(policy, CPUFREQ_GOV_START); |
9591becb | 1312 | if (!ret) |
a1317e09 | 1313 | ret = cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
1bfb425b | 1314 | |
9591becb VK |
1315 | if (ret) |
1316 | pr_err("%s: Failed to start governor\n", __func__); | |
1317 | } | |
cedb70af | 1318 | |
49f18560 | 1319 | goto unlock; |
cedb70af SB |
1320 | } |
1321 | ||
69cee714 VK |
1322 | if (cpufreq_driver->stop_cpu) |
1323 | cpufreq_driver->stop_cpu(policy); | |
87549141 VK |
1324 | |
1325 | /* If cpu is last user of policy, free policy */ | |
1326 | if (has_target()) { | |
a1317e09 | 1327 | ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
559ed407 | 1328 | if (ret) |
87549141 | 1329 | pr_err("%s: Failed to exit governor\n", __func__); |
27ecddc2 | 1330 | } |
1da177e4 | 1331 | |
87549141 VK |
1332 | /* |
1333 | * Perform the ->exit() even during light-weight tear-down, | |
1334 | * since this is a core component, and is essential for the | |
1335 | * subsequent light-weight ->init() to succeed. | |
1336 | */ | |
55582bcc | 1337 | if (cpufreq_driver->exit) { |
87549141 | 1338 | cpufreq_driver->exit(policy); |
55582bcc SP |
1339 | policy->freq_table = NULL; |
1340 | } | |
49f18560 VK |
1341 | |
1342 | unlock: | |
1343 | up_write(&policy->rwsem); | |
1da177e4 LT |
1344 | } |
1345 | ||
cedb70af | 1346 | /** |
27a862e9 | 1347 | * cpufreq_remove_dev - remove a CPU device |
cedb70af SB |
1348 | * |
1349 | * Removes the cpufreq interface for a CPU device. | |
cedb70af | 1350 | */ |
71db87ba | 1351 | static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) |
5a01f2e8 | 1352 | { |
8a25a2fd | 1353 | unsigned int cpu = dev->id; |
559ed407 | 1354 | struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); |
87549141 | 1355 | |
559ed407 | 1356 | if (!policy) |
1af115d6 | 1357 | return; |
87549141 | 1358 | |
69cee714 VK |
1359 | if (cpu_online(cpu)) |
1360 | cpufreq_offline(cpu); | |
87549141 | 1361 | |
559ed407 | 1362 | cpumask_clear_cpu(cpu, policy->real_cpus); |
f344dae0 | 1363 | remove_cpu_dev_symlink(policy, cpu); |
87549141 | 1364 | |
f344dae0 | 1365 | if (cpumask_empty(policy->real_cpus)) |
3654c5cc | 1366 | cpufreq_policy_free(policy, true); |
5a01f2e8 VP |
1367 | } |
1368 | ||
1da177e4 | 1369 | /** |
bb176f7d VK |
1370 | * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're |
1371 | * in deep trouble. | |
a1e1dc41 | 1372 | * @policy: policy managing CPUs |
1da177e4 LT |
1373 | * @new_freq: CPU frequency the CPU actually runs at |
1374 | * | |
29464f28 DJ |
1375 | * We adjust to current frequency first, and need to clean up later. |
1376 | * So either call to cpufreq_update_policy() or schedule handle_update()). | |
1da177e4 | 1377 | */ |
a1e1dc41 | 1378 | static void cpufreq_out_of_sync(struct cpufreq_policy *policy, |
e08f5f5b | 1379 | unsigned int new_freq) |
1da177e4 LT |
1380 | { |
1381 | struct cpufreq_freqs freqs; | |
b43a7ffb | 1382 | |
e837f9b5 | 1383 | pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", |
a1e1dc41 | 1384 | policy->cur, new_freq); |
1da177e4 | 1385 | |
a1e1dc41 | 1386 | freqs.old = policy->cur; |
1da177e4 | 1387 | freqs.new = new_freq; |
b43a7ffb | 1388 | |
8fec051e VK |
1389 | cpufreq_freq_transition_begin(policy, &freqs); |
1390 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1da177e4 LT |
1391 | } |
1392 | ||
32ee8c3e | 1393 | /** |
4ab70df4 | 1394 | * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur |
95235ca2 VP |
1395 | * @cpu: CPU number |
1396 | * | |
1397 | * This is the last known freq, without actually getting it from the driver. | |
1398 | * Return value will be same as what is shown in scaling_cur_freq in sysfs. | |
1399 | */ | |
1400 | unsigned int cpufreq_quick_get(unsigned int cpu) | |
1401 | { | |
9e21ba8b | 1402 | struct cpufreq_policy *policy; |
e08f5f5b | 1403 | unsigned int ret_freq = 0; |
95235ca2 | 1404 | |
1c3d85dd RW |
1405 | if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) |
1406 | return cpufreq_driver->get(cpu); | |
9e21ba8b DB |
1407 | |
1408 | policy = cpufreq_cpu_get(cpu); | |
95235ca2 | 1409 | if (policy) { |
e08f5f5b | 1410 | ret_freq = policy->cur; |
95235ca2 VP |
1411 | cpufreq_cpu_put(policy); |
1412 | } | |
1413 | ||
4d34a67d | 1414 | return ret_freq; |
95235ca2 VP |
1415 | } |
1416 | EXPORT_SYMBOL(cpufreq_quick_get); | |
1417 | ||
3d737108 JB |
1418 | /** |
1419 | * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU | |
1420 | * @cpu: CPU number | |
1421 | * | |
1422 | * Just return the max possible frequency for a given CPU. | |
1423 | */ | |
1424 | unsigned int cpufreq_quick_get_max(unsigned int cpu) | |
1425 | { | |
1426 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
1427 | unsigned int ret_freq = 0; | |
1428 | ||
1429 | if (policy) { | |
1430 | ret_freq = policy->max; | |
1431 | cpufreq_cpu_put(policy); | |
1432 | } | |
1433 | ||
1434 | return ret_freq; | |
1435 | } | |
1436 | EXPORT_SYMBOL(cpufreq_quick_get_max); | |
1437 | ||
d92d50a4 | 1438 | static unsigned int __cpufreq_get(struct cpufreq_policy *policy) |
1da177e4 | 1439 | { |
e08f5f5b | 1440 | unsigned int ret_freq = 0; |
5800043b | 1441 | |
1c3d85dd | 1442 | if (!cpufreq_driver->get) |
4d34a67d | 1443 | return ret_freq; |
1da177e4 | 1444 | |
d92d50a4 | 1445 | ret_freq = cpufreq_driver->get(policy->cpu); |
1da177e4 | 1446 | |
11e584cf VK |
1447 | /* Updating inactive policies is invalid, so avoid doing that. */ |
1448 | if (unlikely(policy_is_inactive(policy))) | |
1449 | return ret_freq; | |
1450 | ||
e08f5f5b | 1451 | if (ret_freq && policy->cur && |
1c3d85dd | 1452 | !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { |
e08f5f5b GS |
1453 | /* verify no discrepancy between actual and |
1454 | saved value exists */ | |
1455 | if (unlikely(ret_freq != policy->cur)) { | |
a1e1dc41 | 1456 | cpufreq_out_of_sync(policy, ret_freq); |
1da177e4 LT |
1457 | schedule_work(&policy->update); |
1458 | } | |
1459 | } | |
1460 | ||
4d34a67d | 1461 | return ret_freq; |
5a01f2e8 | 1462 | } |
1da177e4 | 1463 | |
5a01f2e8 VP |
1464 | /** |
1465 | * cpufreq_get - get the current CPU frequency (in kHz) | |
1466 | * @cpu: CPU number | |
1467 | * | |
1468 | * Get the CPU current (static) CPU frequency | |
1469 | */ | |
1470 | unsigned int cpufreq_get(unsigned int cpu) | |
1471 | { | |
999976e0 | 1472 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
5a01f2e8 | 1473 | unsigned int ret_freq = 0; |
5a01f2e8 | 1474 | |
999976e0 AP |
1475 | if (policy) { |
1476 | down_read(&policy->rwsem); | |
d92d50a4 | 1477 | ret_freq = __cpufreq_get(policy); |
999976e0 | 1478 | up_read(&policy->rwsem); |
5a01f2e8 | 1479 | |
999976e0 AP |
1480 | cpufreq_cpu_put(policy); |
1481 | } | |
6eed9404 | 1482 | |
4d34a67d | 1483 | return ret_freq; |
1da177e4 LT |
1484 | } |
1485 | EXPORT_SYMBOL(cpufreq_get); | |
1486 | ||
8a25a2fd KS |
1487 | static struct subsys_interface cpufreq_interface = { |
1488 | .name = "cpufreq", | |
1489 | .subsys = &cpu_subsys, | |
1490 | .add_dev = cpufreq_add_dev, | |
1491 | .remove_dev = cpufreq_remove_dev, | |
e00e56df RW |
1492 | }; |
1493 | ||
e28867ea VK |
1494 | /* |
1495 | * In case platform wants some specific frequency to be configured | |
1496 | * during suspend.. | |
1497 | */ | |
1498 | int cpufreq_generic_suspend(struct cpufreq_policy *policy) | |
1499 | { | |
1500 | int ret; | |
1501 | ||
1502 | if (!policy->suspend_freq) { | |
201f3716 BZ |
1503 | pr_debug("%s: suspend_freq not defined\n", __func__); |
1504 | return 0; | |
e28867ea VK |
1505 | } |
1506 | ||
1507 | pr_debug("%s: Setting suspend-freq: %u\n", __func__, | |
1508 | policy->suspend_freq); | |
1509 | ||
1510 | ret = __cpufreq_driver_target(policy, policy->suspend_freq, | |
1511 | CPUFREQ_RELATION_H); | |
1512 | if (ret) | |
1513 | pr_err("%s: unable to set suspend-freq: %u. err: %d\n", | |
1514 | __func__, policy->suspend_freq, ret); | |
1515 | ||
1516 | return ret; | |
1517 | } | |
1518 | EXPORT_SYMBOL(cpufreq_generic_suspend); | |
1519 | ||
42d4dc3f | 1520 | /** |
2f0aea93 | 1521 | * cpufreq_suspend() - Suspend CPUFreq governors |
e00e56df | 1522 | * |
2f0aea93 VK |
1523 | * Called during system wide Suspend/Hibernate cycles for suspending governors |
1524 | * as some platforms can't change frequency after this point in suspend cycle. | |
1525 | * Because some of the devices (like: i2c, regulators, etc) they use for | |
1526 | * changing frequency are suspended quickly after this point. | |
42d4dc3f | 1527 | */ |
2f0aea93 | 1528 | void cpufreq_suspend(void) |
42d4dc3f | 1529 | { |
3a3e9e06 | 1530 | struct cpufreq_policy *policy; |
49f18560 | 1531 | int ret; |
42d4dc3f | 1532 | |
2f0aea93 VK |
1533 | if (!cpufreq_driver) |
1534 | return; | |
42d4dc3f | 1535 | |
2f0aea93 | 1536 | if (!has_target()) |
b1b12bab | 1537 | goto suspend; |
42d4dc3f | 1538 | |
2f0aea93 VK |
1539 | pr_debug("%s: Suspending Governors\n", __func__); |
1540 | ||
f963735a | 1541 | for_each_active_policy(policy) { |
49f18560 | 1542 | down_write(&policy->rwsem); |
a1317e09 | 1543 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
49f18560 VK |
1544 | up_write(&policy->rwsem); |
1545 | ||
1546 | if (ret) | |
2f0aea93 VK |
1547 | pr_err("%s: Failed to stop governor for policy: %p\n", |
1548 | __func__, policy); | |
1549 | else if (cpufreq_driver->suspend | |
1550 | && cpufreq_driver->suspend(policy)) | |
1551 | pr_err("%s: Failed to suspend driver: %p\n", __func__, | |
1552 | policy); | |
42d4dc3f | 1553 | } |
b1b12bab VK |
1554 | |
1555 | suspend: | |
1556 | cpufreq_suspended = true; | |
42d4dc3f BH |
1557 | } |
1558 | ||
1da177e4 | 1559 | /** |
2f0aea93 | 1560 | * cpufreq_resume() - Resume CPUFreq governors |
1da177e4 | 1561 | * |
2f0aea93 VK |
1562 | * Called during system wide Suspend/Hibernate cycle for resuming governors that |
1563 | * are suspended with cpufreq_suspend(). | |
1da177e4 | 1564 | */ |
2f0aea93 | 1565 | void cpufreq_resume(void) |
1da177e4 | 1566 | { |
3a3e9e06 | 1567 | struct cpufreq_policy *policy; |
49f18560 | 1568 | int ret; |
1da177e4 | 1569 | |
2f0aea93 VK |
1570 | if (!cpufreq_driver) |
1571 | return; | |
1da177e4 | 1572 | |
8e30444e LT |
1573 | cpufreq_suspended = false; |
1574 | ||
2f0aea93 | 1575 | if (!has_target()) |
e00e56df | 1576 | return; |
1da177e4 | 1577 | |
2f0aea93 | 1578 | pr_debug("%s: Resuming Governors\n", __func__); |
1da177e4 | 1579 | |
f963735a | 1580 | for_each_active_policy(policy) { |
49f18560 | 1581 | if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { |
0c5aa405 VK |
1582 | pr_err("%s: Failed to resume driver: %p\n", __func__, |
1583 | policy); | |
49f18560 VK |
1584 | } else { |
1585 | down_write(&policy->rwsem); | |
a1317e09 | 1586 | ret = cpufreq_governor(policy, CPUFREQ_GOV_START); |
49f18560 | 1587 | if (!ret) |
a1317e09 | 1588 | cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
49f18560 VK |
1589 | up_write(&policy->rwsem); |
1590 | ||
1591 | if (ret) | |
1592 | pr_err("%s: Failed to start governor for policy: %p\n", | |
1593 | __func__, policy); | |
1594 | } | |
2f0aea93 | 1595 | } |
c75de0ac VK |
1596 | |
1597 | /* | |
1598 | * schedule call cpufreq_update_policy() for first-online CPU, as that | |
1599 | * wouldn't be hotplugged-out on suspend. It will verify that the | |
1600 | * current freq is in sync with what we believe it to be. | |
1601 | */ | |
1602 | policy = cpufreq_cpu_get_raw(cpumask_first(cpu_online_mask)); | |
1603 | if (WARN_ON(!policy)) | |
1604 | return; | |
1605 | ||
1606 | schedule_work(&policy->update); | |
2f0aea93 | 1607 | } |
1da177e4 | 1608 | |
9d95046e BP |
1609 | /** |
1610 | * cpufreq_get_current_driver - return current driver's name | |
1611 | * | |
1612 | * Return the name string of the currently loaded cpufreq driver | |
1613 | * or NULL, if none. | |
1614 | */ | |
1615 | const char *cpufreq_get_current_driver(void) | |
1616 | { | |
1c3d85dd RW |
1617 | if (cpufreq_driver) |
1618 | return cpufreq_driver->name; | |
1619 | ||
1620 | return NULL; | |
9d95046e BP |
1621 | } |
1622 | EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); | |
1da177e4 | 1623 | |
51315cdf TP |
1624 | /** |
1625 | * cpufreq_get_driver_data - return current driver data | |
1626 | * | |
1627 | * Return the private data of the currently loaded cpufreq | |
1628 | * driver, or NULL if no cpufreq driver is loaded. | |
1629 | */ | |
1630 | void *cpufreq_get_driver_data(void) | |
1631 | { | |
1632 | if (cpufreq_driver) | |
1633 | return cpufreq_driver->driver_data; | |
1634 | ||
1635 | return NULL; | |
1636 | } | |
1637 | EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); | |
1638 | ||
1da177e4 LT |
1639 | /********************************************************************* |
1640 | * NOTIFIER LISTS INTERFACE * | |
1641 | *********************************************************************/ | |
1642 | ||
1643 | /** | |
1644 | * cpufreq_register_notifier - register a driver with cpufreq | |
1645 | * @nb: notifier function to register | |
1646 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER | |
1647 | * | |
32ee8c3e | 1648 | * Add a driver to one of two lists: either a list of drivers that |
1da177e4 LT |
1649 | * are notified about clock rate changes (once before and once after |
1650 | * the transition), or a list of drivers that are notified about | |
1651 | * changes in cpufreq policy. | |
1652 | * | |
1653 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1654 | * blocking_notifier_chain_register. |
1da177e4 LT |
1655 | */ |
1656 | int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) | |
1657 | { | |
1658 | int ret; | |
1659 | ||
d5aaffa9 DB |
1660 | if (cpufreq_disabled()) |
1661 | return -EINVAL; | |
1662 | ||
74212ca4 CEB |
1663 | WARN_ON(!init_cpufreq_transition_notifier_list_called); |
1664 | ||
1da177e4 LT |
1665 | switch (list) { |
1666 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1667 | ret = srcu_notifier_chain_register( |
e041c683 | 1668 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1669 | break; |
1670 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1671 | ret = blocking_notifier_chain_register( |
1672 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1673 | break; |
1674 | default: | |
1675 | ret = -EINVAL; | |
1676 | } | |
1da177e4 LT |
1677 | |
1678 | return ret; | |
1679 | } | |
1680 | EXPORT_SYMBOL(cpufreq_register_notifier); | |
1681 | ||
1da177e4 LT |
1682 | /** |
1683 | * cpufreq_unregister_notifier - unregister a driver with cpufreq | |
1684 | * @nb: notifier block to be unregistered | |
bb176f7d | 1685 | * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER |
1da177e4 LT |
1686 | * |
1687 | * Remove a driver from the CPU frequency notifier list. | |
1688 | * | |
1689 | * This function may sleep, and has the same return conditions as | |
e041c683 | 1690 | * blocking_notifier_chain_unregister. |
1da177e4 LT |
1691 | */ |
1692 | int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) | |
1693 | { | |
1694 | int ret; | |
1695 | ||
d5aaffa9 DB |
1696 | if (cpufreq_disabled()) |
1697 | return -EINVAL; | |
1698 | ||
1da177e4 LT |
1699 | switch (list) { |
1700 | case CPUFREQ_TRANSITION_NOTIFIER: | |
b4dfdbb3 | 1701 | ret = srcu_notifier_chain_unregister( |
e041c683 | 1702 | &cpufreq_transition_notifier_list, nb); |
1da177e4 LT |
1703 | break; |
1704 | case CPUFREQ_POLICY_NOTIFIER: | |
e041c683 AS |
1705 | ret = blocking_notifier_chain_unregister( |
1706 | &cpufreq_policy_notifier_list, nb); | |
1da177e4 LT |
1707 | break; |
1708 | default: | |
1709 | ret = -EINVAL; | |
1710 | } | |
1da177e4 LT |
1711 | |
1712 | return ret; | |
1713 | } | |
1714 | EXPORT_SYMBOL(cpufreq_unregister_notifier); | |
1715 | ||
1716 | ||
1717 | /********************************************************************* | |
1718 | * GOVERNORS * | |
1719 | *********************************************************************/ | |
1720 | ||
1c03a2d0 VK |
1721 | /* Must set freqs->new to intermediate frequency */ |
1722 | static int __target_intermediate(struct cpufreq_policy *policy, | |
1723 | struct cpufreq_freqs *freqs, int index) | |
1724 | { | |
1725 | int ret; | |
1726 | ||
1727 | freqs->new = cpufreq_driver->get_intermediate(policy, index); | |
1728 | ||
1729 | /* We don't need to switch to intermediate freq */ | |
1730 | if (!freqs->new) | |
1731 | return 0; | |
1732 | ||
1733 | pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", | |
1734 | __func__, policy->cpu, freqs->old, freqs->new); | |
1735 | ||
1736 | cpufreq_freq_transition_begin(policy, freqs); | |
1737 | ret = cpufreq_driver->target_intermediate(policy, index); | |
1738 | cpufreq_freq_transition_end(policy, freqs, ret); | |
1739 | ||
1740 | if (ret) | |
1741 | pr_err("%s: Failed to change to intermediate frequency: %d\n", | |
1742 | __func__, ret); | |
1743 | ||
1744 | return ret; | |
1745 | } | |
1746 | ||
8d65775d VK |
1747 | static int __target_index(struct cpufreq_policy *policy, |
1748 | struct cpufreq_frequency_table *freq_table, int index) | |
1749 | { | |
1c03a2d0 VK |
1750 | struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; |
1751 | unsigned int intermediate_freq = 0; | |
8d65775d VK |
1752 | int retval = -EINVAL; |
1753 | bool notify; | |
1754 | ||
1755 | notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); | |
8d65775d | 1756 | if (notify) { |
1c03a2d0 VK |
1757 | /* Handle switching to intermediate frequency */ |
1758 | if (cpufreq_driver->get_intermediate) { | |
1759 | retval = __target_intermediate(policy, &freqs, index); | |
1760 | if (retval) | |
1761 | return retval; | |
1762 | ||
1763 | intermediate_freq = freqs.new; | |
1764 | /* Set old freq to intermediate */ | |
1765 | if (intermediate_freq) | |
1766 | freqs.old = freqs.new; | |
1767 | } | |
8d65775d | 1768 | |
1c03a2d0 | 1769 | freqs.new = freq_table[index].frequency; |
8d65775d VK |
1770 | pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", |
1771 | __func__, policy->cpu, freqs.old, freqs.new); | |
1772 | ||
1773 | cpufreq_freq_transition_begin(policy, &freqs); | |
1774 | } | |
1775 | ||
1776 | retval = cpufreq_driver->target_index(policy, index); | |
1777 | if (retval) | |
1778 | pr_err("%s: Failed to change cpu frequency: %d\n", __func__, | |
1779 | retval); | |
1780 | ||
1c03a2d0 | 1781 | if (notify) { |
8d65775d VK |
1782 | cpufreq_freq_transition_end(policy, &freqs, retval); |
1783 | ||
1c03a2d0 VK |
1784 | /* |
1785 | * Failed after setting to intermediate freq? Driver should have | |
1786 | * reverted back to initial frequency and so should we. Check | |
1787 | * here for intermediate_freq instead of get_intermediate, in | |
58405af6 | 1788 | * case we haven't switched to intermediate freq at all. |
1c03a2d0 VK |
1789 | */ |
1790 | if (unlikely(retval && intermediate_freq)) { | |
1791 | freqs.old = intermediate_freq; | |
1792 | freqs.new = policy->restore_freq; | |
1793 | cpufreq_freq_transition_begin(policy, &freqs); | |
1794 | cpufreq_freq_transition_end(policy, &freqs, 0); | |
1795 | } | |
1796 | } | |
1797 | ||
8d65775d VK |
1798 | return retval; |
1799 | } | |
1800 | ||
1da177e4 LT |
1801 | int __cpufreq_driver_target(struct cpufreq_policy *policy, |
1802 | unsigned int target_freq, | |
1803 | unsigned int relation) | |
1804 | { | |
7249924e | 1805 | unsigned int old_target_freq = target_freq; |
6019d23a RW |
1806 | struct cpufreq_frequency_table *freq_table; |
1807 | int index, retval; | |
c32b6b8e | 1808 | |
a7b422cd KRW |
1809 | if (cpufreq_disabled()) |
1810 | return -ENODEV; | |
1811 | ||
7249924e VK |
1812 | /* Make sure that target_freq is within supported range */ |
1813 | if (target_freq > policy->max) | |
1814 | target_freq = policy->max; | |
1815 | if (target_freq < policy->min) | |
1816 | target_freq = policy->min; | |
1817 | ||
1818 | pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", | |
e837f9b5 | 1819 | policy->cpu, target_freq, relation, old_target_freq); |
5a1c0228 | 1820 | |
9c0ebcf7 VK |
1821 | /* |
1822 | * This might look like a redundant call as we are checking it again | |
1823 | * after finding index. But it is left intentionally for cases where | |
1824 | * exactly same freq is called again and so we can save on few function | |
1825 | * calls. | |
1826 | */ | |
5a1c0228 VK |
1827 | if (target_freq == policy->cur) |
1828 | return 0; | |
1829 | ||
1c03a2d0 VK |
1830 | /* Save last value to restore later on errors */ |
1831 | policy->restore_freq = policy->cur; | |
1832 | ||
1c3d85dd | 1833 | if (cpufreq_driver->target) |
6019d23a | 1834 | return cpufreq_driver->target(policy, target_freq, relation); |
9c0ebcf7 | 1835 | |
6019d23a RW |
1836 | if (!cpufreq_driver->target_index) |
1837 | return -EINVAL; | |
9c0ebcf7 | 1838 | |
6019d23a RW |
1839 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
1840 | if (unlikely(!freq_table)) { | |
1841 | pr_err("%s: Unable to find freq_table\n", __func__); | |
1842 | return -EINVAL; | |
1843 | } | |
d4019f0a | 1844 | |
6019d23a RW |
1845 | retval = cpufreq_frequency_table_target(policy, freq_table, target_freq, |
1846 | relation, &index); | |
1847 | if (unlikely(retval)) { | |
1848 | pr_err("%s: Unable to find matching freq\n", __func__); | |
1849 | return retval; | |
9c0ebcf7 VK |
1850 | } |
1851 | ||
6019d23a RW |
1852 | if (freq_table[index].frequency == policy->cur) |
1853 | return 0; | |
1854 | ||
1855 | return __target_index(policy, freq_table, index); | |
1da177e4 LT |
1856 | } |
1857 | EXPORT_SYMBOL_GPL(__cpufreq_driver_target); | |
1858 | ||
1da177e4 LT |
1859 | int cpufreq_driver_target(struct cpufreq_policy *policy, |
1860 | unsigned int target_freq, | |
1861 | unsigned int relation) | |
1862 | { | |
f1829e4a | 1863 | int ret = -EINVAL; |
1da177e4 | 1864 | |
ad7722da | 1865 | down_write(&policy->rwsem); |
1da177e4 LT |
1866 | |
1867 | ret = __cpufreq_driver_target(policy, target_freq, relation); | |
1868 | ||
ad7722da | 1869 | up_write(&policy->rwsem); |
1da177e4 | 1870 | |
1da177e4 LT |
1871 | return ret; |
1872 | } | |
1873 | EXPORT_SYMBOL_GPL(cpufreq_driver_target); | |
1874 | ||
de1df26b RW |
1875 | __weak struct cpufreq_governor *cpufreq_fallback_governor(void) |
1876 | { | |
1877 | return NULL; | |
1878 | } | |
1879 | ||
a1317e09 | 1880 | static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event) |
1da177e4 | 1881 | { |
cc993cab | 1882 | int ret; |
6afde10c | 1883 | |
2f0aea93 VK |
1884 | /* Don't start any governor operations if we are entering suspend */ |
1885 | if (cpufreq_suspended) | |
1886 | return 0; | |
cb57720b EZ |
1887 | /* |
1888 | * Governor might not be initiated here if ACPI _PPC changed | |
1889 | * notification happened, so check it. | |
1890 | */ | |
1891 | if (!policy->governor) | |
1892 | return -EINVAL; | |
2f0aea93 | 1893 | |
1c256245 TR |
1894 | if (policy->governor->max_transition_latency && |
1895 | policy->cpuinfo.transition_latency > | |
1896 | policy->governor->max_transition_latency) { | |
de1df26b RW |
1897 | struct cpufreq_governor *gov = cpufreq_fallback_governor(); |
1898 | ||
1899 | if (gov) { | |
e837f9b5 JP |
1900 | pr_warn("%s governor failed, too long transition latency of HW, fallback to %s governor\n", |
1901 | policy->governor->name, gov->name); | |
6afde10c | 1902 | policy->governor = gov; |
de1df26b RW |
1903 | } else { |
1904 | return -EINVAL; | |
6afde10c | 1905 | } |
1c256245 | 1906 | } |
1da177e4 | 1907 | |
fe492f3f VK |
1908 | if (event == CPUFREQ_GOV_POLICY_INIT) |
1909 | if (!try_module_get(policy->governor->owner)) | |
1910 | return -EINVAL; | |
1da177e4 | 1911 | |
63431f78 | 1912 | pr_debug("%s: for CPU %u, event %u\n", __func__, policy->cpu, event); |
95731ebb | 1913 | |
1da177e4 LT |
1914 | ret = policy->governor->governor(policy, event); |
1915 | ||
4d5dcc42 VK |
1916 | if (!ret) { |
1917 | if (event == CPUFREQ_GOV_POLICY_INIT) | |
1918 | policy->governor->initialized++; | |
1919 | else if (event == CPUFREQ_GOV_POLICY_EXIT) | |
1920 | policy->governor->initialized--; | |
1921 | } | |
b394058f | 1922 | |
fe492f3f VK |
1923 | if (((event == CPUFREQ_GOV_POLICY_INIT) && ret) || |
1924 | ((event == CPUFREQ_GOV_POLICY_EXIT) && !ret)) | |
1da177e4 LT |
1925 | module_put(policy->governor->owner); |
1926 | ||
1927 | return ret; | |
1928 | } | |
1929 | ||
1da177e4 LT |
1930 | int cpufreq_register_governor(struct cpufreq_governor *governor) |
1931 | { | |
3bcb09a3 | 1932 | int err; |
1da177e4 LT |
1933 | |
1934 | if (!governor) | |
1935 | return -EINVAL; | |
1936 | ||
a7b422cd KRW |
1937 | if (cpufreq_disabled()) |
1938 | return -ENODEV; | |
1939 | ||
3fc54d37 | 1940 | mutex_lock(&cpufreq_governor_mutex); |
32ee8c3e | 1941 | |
b394058f | 1942 | governor->initialized = 0; |
3bcb09a3 | 1943 | err = -EBUSY; |
42f91fa1 | 1944 | if (!find_governor(governor->name)) { |
3bcb09a3 JF |
1945 | err = 0; |
1946 | list_add(&governor->governor_list, &cpufreq_governor_list); | |
1da177e4 | 1947 | } |
1da177e4 | 1948 | |
32ee8c3e | 1949 | mutex_unlock(&cpufreq_governor_mutex); |
3bcb09a3 | 1950 | return err; |
1da177e4 LT |
1951 | } |
1952 | EXPORT_SYMBOL_GPL(cpufreq_register_governor); | |
1953 | ||
1da177e4 LT |
1954 | void cpufreq_unregister_governor(struct cpufreq_governor *governor) |
1955 | { | |
4573237b VK |
1956 | struct cpufreq_policy *policy; |
1957 | unsigned long flags; | |
90e41bac | 1958 | |
1da177e4 LT |
1959 | if (!governor) |
1960 | return; | |
1961 | ||
a7b422cd KRW |
1962 | if (cpufreq_disabled()) |
1963 | return; | |
1964 | ||
4573237b VK |
1965 | /* clear last_governor for all inactive policies */ |
1966 | read_lock_irqsave(&cpufreq_driver_lock, flags); | |
1967 | for_each_inactive_policy(policy) { | |
18bf3a12 VK |
1968 | if (!strcmp(policy->last_governor, governor->name)) { |
1969 | policy->governor = NULL; | |
4573237b | 1970 | strcpy(policy->last_governor, "\0"); |
18bf3a12 | 1971 | } |
90e41bac | 1972 | } |
4573237b | 1973 | read_unlock_irqrestore(&cpufreq_driver_lock, flags); |
90e41bac | 1974 | |
3fc54d37 | 1975 | mutex_lock(&cpufreq_governor_mutex); |
1da177e4 | 1976 | list_del(&governor->governor_list); |
3fc54d37 | 1977 | mutex_unlock(&cpufreq_governor_mutex); |
1da177e4 LT |
1978 | return; |
1979 | } | |
1980 | EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); | |
1981 | ||
1982 | ||
1da177e4 LT |
1983 | /********************************************************************* |
1984 | * POLICY INTERFACE * | |
1985 | *********************************************************************/ | |
1986 | ||
1987 | /** | |
1988 | * cpufreq_get_policy - get the current cpufreq_policy | |
29464f28 DJ |
1989 | * @policy: struct cpufreq_policy into which the current cpufreq_policy |
1990 | * is written | |
1da177e4 LT |
1991 | * |
1992 | * Reads the current cpufreq policy. | |
1993 | */ | |
1994 | int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) | |
1995 | { | |
1996 | struct cpufreq_policy *cpu_policy; | |
1997 | if (!policy) | |
1998 | return -EINVAL; | |
1999 | ||
2000 | cpu_policy = cpufreq_cpu_get(cpu); | |
2001 | if (!cpu_policy) | |
2002 | return -EINVAL; | |
2003 | ||
d5b73cd8 | 2004 | memcpy(policy, cpu_policy, sizeof(*policy)); |
1da177e4 LT |
2005 | |
2006 | cpufreq_cpu_put(cpu_policy); | |
1da177e4 LT |
2007 | return 0; |
2008 | } | |
2009 | EXPORT_SYMBOL(cpufreq_get_policy); | |
2010 | ||
153d7f3f | 2011 | /* |
037ce839 VK |
2012 | * policy : current policy. |
2013 | * new_policy: policy to be set. | |
153d7f3f | 2014 | */ |
037ce839 | 2015 | static int cpufreq_set_policy(struct cpufreq_policy *policy, |
3a3e9e06 | 2016 | struct cpufreq_policy *new_policy) |
1da177e4 | 2017 | { |
d9a789c7 RW |
2018 | struct cpufreq_governor *old_gov; |
2019 | int ret; | |
1da177e4 | 2020 | |
e837f9b5 JP |
2021 | pr_debug("setting new policy for CPU %u: %u - %u kHz\n", |
2022 | new_policy->cpu, new_policy->min, new_policy->max); | |
1da177e4 | 2023 | |
d5b73cd8 | 2024 | memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); |
1da177e4 | 2025 | |
fba9573b PX |
2026 | /* |
2027 | * This check works well when we store new min/max freq attributes, | |
2028 | * because new_policy is a copy of policy with one field updated. | |
2029 | */ | |
2030 | if (new_policy->min > new_policy->max) | |
d9a789c7 | 2031 | return -EINVAL; |
9c9a43ed | 2032 | |
1da177e4 | 2033 | /* verify the cpu speed can be set within this limit */ |
3a3e9e06 | 2034 | ret = cpufreq_driver->verify(new_policy); |
1da177e4 | 2035 | if (ret) |
d9a789c7 | 2036 | return ret; |
1da177e4 | 2037 | |
1da177e4 | 2038 | /* adjust if necessary - all reasons */ |
e041c683 | 2039 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2040 | CPUFREQ_ADJUST, new_policy); |
1da177e4 | 2041 | |
bb176f7d VK |
2042 | /* |
2043 | * verify the cpu speed can be set within this limit, which might be | |
2044 | * different to the first one | |
2045 | */ | |
3a3e9e06 | 2046 | ret = cpufreq_driver->verify(new_policy); |
e041c683 | 2047 | if (ret) |
d9a789c7 | 2048 | return ret; |
1da177e4 LT |
2049 | |
2050 | /* notification of the new policy */ | |
e041c683 | 2051 | blocking_notifier_call_chain(&cpufreq_policy_notifier_list, |
3a3e9e06 | 2052 | CPUFREQ_NOTIFY, new_policy); |
1da177e4 | 2053 | |
3a3e9e06 VK |
2054 | policy->min = new_policy->min; |
2055 | policy->max = new_policy->max; | |
1da177e4 | 2056 | |
2d06d8c4 | 2057 | pr_debug("new min and max freqs are %u - %u kHz\n", |
e837f9b5 | 2058 | policy->min, policy->max); |
1da177e4 | 2059 | |
1c3d85dd | 2060 | if (cpufreq_driver->setpolicy) { |
3a3e9e06 | 2061 | policy->policy = new_policy->policy; |
2d06d8c4 | 2062 | pr_debug("setting range\n"); |
d9a789c7 RW |
2063 | return cpufreq_driver->setpolicy(new_policy); |
2064 | } | |
1da177e4 | 2065 | |
d9a789c7 RW |
2066 | if (new_policy->governor == policy->governor) |
2067 | goto out; | |
7bd353a9 | 2068 | |
d9a789c7 RW |
2069 | pr_debug("governor switch\n"); |
2070 | ||
2071 | /* save old, working values */ | |
2072 | old_gov = policy->governor; | |
2073 | /* end old governor */ | |
2074 | if (old_gov) { | |
a1317e09 | 2075 | ret = cpufreq_governor(policy, CPUFREQ_GOV_STOP); |
4bc384ae VK |
2076 | if (ret) { |
2077 | /* This can happen due to race with other operations */ | |
2078 | pr_debug("%s: Failed to Stop Governor: %s (%d)\n", | |
2079 | __func__, old_gov->name, ret); | |
2080 | return ret; | |
2081 | } | |
2082 | ||
a1317e09 | 2083 | ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
4bc384ae VK |
2084 | if (ret) { |
2085 | pr_err("%s: Failed to Exit Governor: %s (%d)\n", | |
2086 | __func__, old_gov->name, ret); | |
2087 | return ret; | |
2088 | } | |
1da177e4 LT |
2089 | } |
2090 | ||
d9a789c7 RW |
2091 | /* start new governor */ |
2092 | policy->governor = new_policy->governor; | |
a1317e09 | 2093 | ret = cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT); |
4bc384ae | 2094 | if (!ret) { |
a1317e09 | 2095 | ret = cpufreq_governor(policy, CPUFREQ_GOV_START); |
4bc384ae | 2096 | if (!ret) |
d9a789c7 RW |
2097 | goto out; |
2098 | ||
a1317e09 | 2099 | cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT); |
d9a789c7 RW |
2100 | } |
2101 | ||
2102 | /* new governor failed, so re-start old one */ | |
2103 | pr_debug("starting governor %s failed\n", policy->governor->name); | |
2104 | if (old_gov) { | |
2105 | policy->governor = old_gov; | |
a1317e09 | 2106 | if (cpufreq_governor(policy, CPUFREQ_GOV_POLICY_INIT)) |
4bc384ae VK |
2107 | policy->governor = NULL; |
2108 | else | |
a1317e09 | 2109 | cpufreq_governor(policy, CPUFREQ_GOV_START); |
d9a789c7 RW |
2110 | } |
2111 | ||
4bc384ae | 2112 | return ret; |
d9a789c7 RW |
2113 | |
2114 | out: | |
2115 | pr_debug("governor: change or update limits\n"); | |
a1317e09 | 2116 | return cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
1da177e4 LT |
2117 | } |
2118 | ||
1da177e4 LT |
2119 | /** |
2120 | * cpufreq_update_policy - re-evaluate an existing cpufreq policy | |
2121 | * @cpu: CPU which shall be re-evaluated | |
2122 | * | |
25985edc | 2123 | * Useful for policy notifiers which have different necessities |
1da177e4 LT |
2124 | * at different times. |
2125 | */ | |
2126 | int cpufreq_update_policy(unsigned int cpu) | |
2127 | { | |
3a3e9e06 VK |
2128 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
2129 | struct cpufreq_policy new_policy; | |
f1829e4a | 2130 | int ret; |
1da177e4 | 2131 | |
fefa8ff8 AP |
2132 | if (!policy) |
2133 | return -ENODEV; | |
1da177e4 | 2134 | |
ad7722da | 2135 | down_write(&policy->rwsem); |
1da177e4 | 2136 | |
2d06d8c4 | 2137 | pr_debug("updating policy for CPU %u\n", cpu); |
d5b73cd8 | 2138 | memcpy(&new_policy, policy, sizeof(*policy)); |
3a3e9e06 VK |
2139 | new_policy.min = policy->user_policy.min; |
2140 | new_policy.max = policy->user_policy.max; | |
1da177e4 | 2141 | |
bb176f7d VK |
2142 | /* |
2143 | * BIOS might change freq behind our back | |
2144 | * -> ask driver for current freq and notify governors about a change | |
2145 | */ | |
2ed99e39 | 2146 | if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { |
3a3e9e06 | 2147 | new_policy.cur = cpufreq_driver->get(cpu); |
bd0fa9bb VK |
2148 | if (WARN_ON(!new_policy.cur)) { |
2149 | ret = -EIO; | |
fefa8ff8 | 2150 | goto unlock; |
bd0fa9bb VK |
2151 | } |
2152 | ||
3a3e9e06 | 2153 | if (!policy->cur) { |
e837f9b5 | 2154 | pr_debug("Driver did not initialize current freq\n"); |
3a3e9e06 | 2155 | policy->cur = new_policy.cur; |
a85f7bd3 | 2156 | } else { |
9c0ebcf7 | 2157 | if (policy->cur != new_policy.cur && has_target()) |
a1e1dc41 | 2158 | cpufreq_out_of_sync(policy, new_policy.cur); |
a85f7bd3 | 2159 | } |
0961dd0d TR |
2160 | } |
2161 | ||
037ce839 | 2162 | ret = cpufreq_set_policy(policy, &new_policy); |
1da177e4 | 2163 | |
fefa8ff8 | 2164 | unlock: |
ad7722da | 2165 | up_write(&policy->rwsem); |
5a01f2e8 | 2166 | |
3a3e9e06 | 2167 | cpufreq_cpu_put(policy); |
1da177e4 LT |
2168 | return ret; |
2169 | } | |
2170 | EXPORT_SYMBOL(cpufreq_update_policy); | |
2171 | ||
2760984f | 2172 | static int cpufreq_cpu_callback(struct notifier_block *nfb, |
c32b6b8e AR |
2173 | unsigned long action, void *hcpu) |
2174 | { | |
2175 | unsigned int cpu = (unsigned long)hcpu; | |
c32b6b8e | 2176 | |
0b275352 RW |
2177 | switch (action & ~CPU_TASKS_FROZEN) { |
2178 | case CPU_ONLINE: | |
2179 | cpufreq_online(cpu); | |
2180 | break; | |
5302c3fb | 2181 | |
0b275352 | 2182 | case CPU_DOWN_PREPARE: |
69cee714 | 2183 | cpufreq_offline(cpu); |
0b275352 | 2184 | break; |
5302c3fb | 2185 | |
0b275352 RW |
2186 | case CPU_DOWN_FAILED: |
2187 | cpufreq_online(cpu); | |
2188 | break; | |
c32b6b8e AR |
2189 | } |
2190 | return NOTIFY_OK; | |
2191 | } | |
2192 | ||
9c36f746 | 2193 | static struct notifier_block __refdata cpufreq_cpu_notifier = { |
bb176f7d | 2194 | .notifier_call = cpufreq_cpu_callback, |
c32b6b8e | 2195 | }; |
1da177e4 | 2196 | |
6f19efc0 LM |
2197 | /********************************************************************* |
2198 | * BOOST * | |
2199 | *********************************************************************/ | |
2200 | static int cpufreq_boost_set_sw(int state) | |
2201 | { | |
2202 | struct cpufreq_frequency_table *freq_table; | |
2203 | struct cpufreq_policy *policy; | |
2204 | int ret = -EINVAL; | |
2205 | ||
f963735a | 2206 | for_each_active_policy(policy) { |
6f19efc0 LM |
2207 | freq_table = cpufreq_frequency_get_table(policy->cpu); |
2208 | if (freq_table) { | |
2209 | ret = cpufreq_frequency_table_cpuinfo(policy, | |
2210 | freq_table); | |
2211 | if (ret) { | |
2212 | pr_err("%s: Policy frequency update failed\n", | |
2213 | __func__); | |
2214 | break; | |
2215 | } | |
49f18560 VK |
2216 | |
2217 | down_write(&policy->rwsem); | |
6f19efc0 | 2218 | policy->user_policy.max = policy->max; |
a1317e09 | 2219 | cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); |
49f18560 | 2220 | up_write(&policy->rwsem); |
6f19efc0 LM |
2221 | } |
2222 | } | |
2223 | ||
2224 | return ret; | |
2225 | } | |
2226 | ||
2227 | int cpufreq_boost_trigger_state(int state) | |
2228 | { | |
2229 | unsigned long flags; | |
2230 | int ret = 0; | |
2231 | ||
2232 | if (cpufreq_driver->boost_enabled == state) | |
2233 | return 0; | |
2234 | ||
2235 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2236 | cpufreq_driver->boost_enabled = state; | |
2237 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2238 | ||
2239 | ret = cpufreq_driver->set_boost(state); | |
2240 | if (ret) { | |
2241 | write_lock_irqsave(&cpufreq_driver_lock, flags); | |
2242 | cpufreq_driver->boost_enabled = !state; | |
2243 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); | |
2244 | ||
e837f9b5 JP |
2245 | pr_err("%s: Cannot %s BOOST\n", |
2246 | __func__, state ? "enable" : "disable"); | |
6f19efc0 LM |
2247 | } |
2248 | ||
2249 | return ret; | |
2250 | } | |
2251 | ||
41669da0 | 2252 | static bool cpufreq_boost_supported(void) |
6f19efc0 | 2253 | { |
7a6c79f2 | 2254 | return likely(cpufreq_driver) && cpufreq_driver->set_boost; |
6f19efc0 | 2255 | } |
6f19efc0 | 2256 | |
44139ed4 VK |
2257 | static int create_boost_sysfs_file(void) |
2258 | { | |
2259 | int ret; | |
2260 | ||
c82bd444 | 2261 | ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2262 | if (ret) |
2263 | pr_err("%s: cannot register global BOOST sysfs file\n", | |
2264 | __func__); | |
2265 | ||
2266 | return ret; | |
2267 | } | |
2268 | ||
2269 | static void remove_boost_sysfs_file(void) | |
2270 | { | |
2271 | if (cpufreq_boost_supported()) | |
c82bd444 | 2272 | sysfs_remove_file(cpufreq_global_kobject, &boost.attr); |
44139ed4 VK |
2273 | } |
2274 | ||
2275 | int cpufreq_enable_boost_support(void) | |
2276 | { | |
2277 | if (!cpufreq_driver) | |
2278 | return -EINVAL; | |
2279 | ||
2280 | if (cpufreq_boost_supported()) | |
2281 | return 0; | |
2282 | ||
7a6c79f2 | 2283 | cpufreq_driver->set_boost = cpufreq_boost_set_sw; |
44139ed4 VK |
2284 | |
2285 | /* This will get removed on driver unregister */ | |
2286 | return create_boost_sysfs_file(); | |
2287 | } | |
2288 | EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); | |
2289 | ||
6f19efc0 LM |
2290 | int cpufreq_boost_enabled(void) |
2291 | { | |
2292 | return cpufreq_driver->boost_enabled; | |
2293 | } | |
2294 | EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); | |
2295 | ||
1da177e4 LT |
2296 | /********************************************************************* |
2297 | * REGISTER / UNREGISTER CPUFREQ DRIVER * | |
2298 | *********************************************************************/ | |
2299 | ||
2300 | /** | |
2301 | * cpufreq_register_driver - register a CPU Frequency driver | |
2302 | * @driver_data: A struct cpufreq_driver containing the values# | |
2303 | * submitted by the CPU Frequency driver. | |
2304 | * | |
bb176f7d | 2305 | * Registers a CPU Frequency driver to this core code. This code |
63af4055 | 2306 | * returns zero on success, -EEXIST when another driver got here first |
32ee8c3e | 2307 | * (and isn't unregistered in the meantime). |
1da177e4 LT |
2308 | * |
2309 | */ | |
221dee28 | 2310 | int cpufreq_register_driver(struct cpufreq_driver *driver_data) |
1da177e4 LT |
2311 | { |
2312 | unsigned long flags; | |
2313 | int ret; | |
2314 | ||
a7b422cd KRW |
2315 | if (cpufreq_disabled()) |
2316 | return -ENODEV; | |
2317 | ||
1da177e4 | 2318 | if (!driver_data || !driver_data->verify || !driver_data->init || |
9c0ebcf7 | 2319 | !(driver_data->setpolicy || driver_data->target_index || |
9832235f RW |
2320 | driver_data->target) || |
2321 | (driver_data->setpolicy && (driver_data->target_index || | |
1c03a2d0 VK |
2322 | driver_data->target)) || |
2323 | (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) | |
1da177e4 LT |
2324 | return -EINVAL; |
2325 | ||
2d06d8c4 | 2326 | pr_debug("trying to register driver %s\n", driver_data->name); |
1da177e4 | 2327 | |
fdd320da RW |
2328 | /* Protect against concurrent CPU online/offline. */ |
2329 | get_online_cpus(); | |
2330 | ||
0d1857a1 | 2331 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2332 | if (cpufreq_driver) { |
0d1857a1 | 2333 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da RW |
2334 | ret = -EEXIST; |
2335 | goto out; | |
1da177e4 | 2336 | } |
1c3d85dd | 2337 | cpufreq_driver = driver_data; |
0d1857a1 | 2338 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
1da177e4 | 2339 | |
bc68b7df VK |
2340 | if (driver_data->setpolicy) |
2341 | driver_data->flags |= CPUFREQ_CONST_LOOPS; | |
2342 | ||
7a6c79f2 RW |
2343 | if (cpufreq_boost_supported()) { |
2344 | ret = create_boost_sysfs_file(); | |
2345 | if (ret) | |
2346 | goto err_null_driver; | |
2347 | } | |
6f19efc0 | 2348 | |
8a25a2fd | 2349 | ret = subsys_interface_register(&cpufreq_interface); |
8f5bc2ab | 2350 | if (ret) |
6f19efc0 | 2351 | goto err_boost_unreg; |
1da177e4 | 2352 | |
ce1bcfe9 VK |
2353 | if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && |
2354 | list_empty(&cpufreq_policy_list)) { | |
1da177e4 | 2355 | /* if all ->init() calls failed, unregister */ |
ce1bcfe9 VK |
2356 | pr_debug("%s: No CPU initialized for driver %s\n", __func__, |
2357 | driver_data->name); | |
2358 | goto err_if_unreg; | |
1da177e4 LT |
2359 | } |
2360 | ||
8f5bc2ab | 2361 | register_hotcpu_notifier(&cpufreq_cpu_notifier); |
2d06d8c4 | 2362 | pr_debug("driver %s up and running\n", driver_data->name); |
1da177e4 | 2363 | |
fdd320da RW |
2364 | out: |
2365 | put_online_cpus(); | |
2366 | return ret; | |
2367 | ||
8a25a2fd KS |
2368 | err_if_unreg: |
2369 | subsys_interface_unregister(&cpufreq_interface); | |
6f19efc0 | 2370 | err_boost_unreg: |
44139ed4 | 2371 | remove_boost_sysfs_file(); |
8f5bc2ab | 2372 | err_null_driver: |
0d1857a1 | 2373 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
1c3d85dd | 2374 | cpufreq_driver = NULL; |
0d1857a1 | 2375 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
fdd320da | 2376 | goto out; |
1da177e4 LT |
2377 | } |
2378 | EXPORT_SYMBOL_GPL(cpufreq_register_driver); | |
2379 | ||
1da177e4 LT |
2380 | /** |
2381 | * cpufreq_unregister_driver - unregister the current CPUFreq driver | |
2382 | * | |
bb176f7d | 2383 | * Unregister the current CPUFreq driver. Only call this if you have |
1da177e4 LT |
2384 | * the right to do so, i.e. if you have succeeded in initialising before! |
2385 | * Returns zero if successful, and -EINVAL if the cpufreq_driver is | |
2386 | * currently not initialised. | |
2387 | */ | |
221dee28 | 2388 | int cpufreq_unregister_driver(struct cpufreq_driver *driver) |
1da177e4 LT |
2389 | { |
2390 | unsigned long flags; | |
2391 | ||
1c3d85dd | 2392 | if (!cpufreq_driver || (driver != cpufreq_driver)) |
1da177e4 | 2393 | return -EINVAL; |
1da177e4 | 2394 | |
2d06d8c4 | 2395 | pr_debug("unregistering driver %s\n", driver->name); |
1da177e4 | 2396 | |
454d3a25 SAS |
2397 | /* Protect against concurrent cpu hotplug */ |
2398 | get_online_cpus(); | |
8a25a2fd | 2399 | subsys_interface_unregister(&cpufreq_interface); |
44139ed4 | 2400 | remove_boost_sysfs_file(); |
65edc68c | 2401 | unregister_hotcpu_notifier(&cpufreq_cpu_notifier); |
1da177e4 | 2402 | |
0d1857a1 | 2403 | write_lock_irqsave(&cpufreq_driver_lock, flags); |
6eed9404 | 2404 | |
1c3d85dd | 2405 | cpufreq_driver = NULL; |
6eed9404 | 2406 | |
0d1857a1 | 2407 | write_unlock_irqrestore(&cpufreq_driver_lock, flags); |
454d3a25 | 2408 | put_online_cpus(); |
1da177e4 LT |
2409 | |
2410 | return 0; | |
2411 | } | |
2412 | EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); | |
5a01f2e8 | 2413 | |
90de2a4a DA |
2414 | /* |
2415 | * Stop cpufreq at shutdown to make sure it isn't holding any locks | |
2416 | * or mutexes when secondary CPUs are halted. | |
2417 | */ | |
2418 | static struct syscore_ops cpufreq_syscore_ops = { | |
2419 | .shutdown = cpufreq_suspend, | |
2420 | }; | |
2421 | ||
c82bd444 VK |
2422 | struct kobject *cpufreq_global_kobject; |
2423 | EXPORT_SYMBOL(cpufreq_global_kobject); | |
2424 | ||
5a01f2e8 VP |
2425 | static int __init cpufreq_core_init(void) |
2426 | { | |
a7b422cd KRW |
2427 | if (cpufreq_disabled()) |
2428 | return -ENODEV; | |
2429 | ||
8eec1020 | 2430 | cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); |
8aa84ad8 TR |
2431 | BUG_ON(!cpufreq_global_kobject); |
2432 | ||
90de2a4a DA |
2433 | register_syscore_ops(&cpufreq_syscore_ops); |
2434 | ||
5a01f2e8 VP |
2435 | return 0; |
2436 | } | |
5a01f2e8 | 2437 | core_initcall(cpufreq_core_init); |